Serum concentrations of feline pancreatic lipase immunoreactivity (fPLI), feline trypsin-like immunoreactivity (fTLI), and cobalamin are commonly used for the diagnostic investigation of cats with gastrointestinal signs. No information on these parameters in healthy cats less than 1 year of age exists. We aimed to evaluate serum concentrations of fPLI, fTLI, and cobalamin in healthy cats at different time-points during their first 12 months of life. Fourteen healthy 2-month-old kittens were included. Blood was collected at 2, 3, 4, 6, and 12 months of age, and serum concentrations of fPLI, fTLI, and cobalamin were measured. Serum fPLI and fTLI concentrations did not show any statistically or clinically significant differences in young kittens. In contrast, serum cobalamin concentrations were commonly below the reference interval in kittens. Serum fPLI and fTLI concentrations are not practically affected by age in kittens as young as 2 months of age and could be used for the investigation of pancreatic diseases.Serum concentrations of feline pancreatic lipase immunoreactivity (fPLI), feline trypsin-like immunoreactivity (fTLI), and cobalamin are commonly used for the diagnostic investigation of cats with gastrointestinal signs. No information on these parameters in healthy cats less than 1 year of age exists. We aimed to evaluate serum concentrations of fPLI, fTLI, and cobalamin in healthy cats at different time-points during their first 12 months of life. Fourteen healthy 2-month-old kittens were included. Blood was collected at 2, 3, 4, 6, and 12 months of age, and serum concentrations of fPLI, fTLI, and cobalamin were measured. While there was a statistically significant difference in serum fPLI concentrations over time, there was no statistically significant difference between individual time-points. There was no significant difference in serum fTLI concentrations over time. Serum cobalamin concentrations were below the reference interval in 3/13 cats at 2 months of age and were significantly lower by 3 months, when 13/14 had hypocobalaminemia. By 12 months, serum cobalamin had significantly increased, yet 4/12 cats still had hypocobalaminemia. Serum fPLI and fTLI concentrations did not show any statistically or clinically significant differences in young kittens. In contrast, serum cobalamin concentrations were commonly below the reference interval in kittens. Serum fPLI and fTLI concentrations are not practically affected by age in kittens as young as 2 months of age and could be used for the investigation of pancreatic diseases. Serum concentrations of feline pancreatic lipase immunoreactivity (fPLI), feline trypsin-like immunoreactivity (fTLI), and cobalamin are commonly used for the diagnostic investigation of cats with gastrointestinal (GI) signs. Although GI and pancreatic diseases are more common in older cats, several studies have shown that certain conditions, such as food-responsive enteropathy (FRE), pancreatitis, and exocrine pancreatic insufficiency (EPI) can occur in young cats, even below the age of 1 year ,3,4. HowMeasurement of serum fPLI concentration is considered to be the serum test of choice for the diagnosis of pancreatitis in cats, with a reported sensitivity ranging between 67% and 100% and a reported specificity of 82–100% ,6,7,8. SOur hypothesis was that serum fPLI, fTLI, and cobalamin concentrations would not be affected by age in young cats. We aimed to evaluate serum concentrations of fPLI, fTLI, and cobalamin in cats at different time-points during the first 12 months of their life.The study protocol was reviewed and approved by the Animal Ethics Committee of the University of Thessaly, Greece (AUP number: 54/13.2.2018).A total of 23 domestic shorthair (DSH) kittens, approximately 2 months of age, were prospectively enrolled into the study, but only 14 of them were followed up until they reached 1 year of age. The age of the cats was estimated based on body size, dentition, and other physical characteristics ,18,19.ThUpon admission, a thorough physical examination was performed in all cats, including evaluation of mental status, hydration status, body weight (BW), body condition score (BCS), gender, heart rate and rhythm, mucous membranes color, capillary refill time, respiratory rate, thoracic auscultation, abdominal palpation, and body temperature. In addition, all cats were kept at the Clinic to be observed for a few days, and the presence of diarrhea, vomiting, decreased or increased appetite, and other clinical signs were recorded. Cats were included in the study if they were deemed to be healthy, apart from mild conditions that are not expected to affect gastrointestinal function or serum fPLI, fTLI, and cobalamin concentrations . Cats were excluded from the study if they had concurrent health conditions that were severe enough to require specific treatments and/or hospitalization.Prior to inclusion into the study, all kittens received the same antiparasitic treatment -methoprene, eprinomectin, and praziquantel; Broadline, Boehringer Ingelheim International GmbH, Rhein, Germany) topically, and remained on the same monthly antiparasitic treatment throughout the study period. All were tested for feline leukemia virus (FeLV) antigen and feline immunodeficiency virus (FIV) antibodies  and for canine parvovirus antigen , and were vaccinated  according to recent guidelines .Finally, all cats consumed the same commercial diet  exclusively during the whole study period. The percentage of crude protein, crude oils and fats, crude fiber, crude ash, calcium, phosphorus, omega 6 essential fatty acids, and omega 3 essential fatty acids was 34%, 15%, 2.5%, 8.5%, 1.1%, 1%, 2.67%, and 1% respectively. The metabolizable energy was 4000 Kcal/kg dry matter.g for 10 min, and serum was collected, placed into Eppendorf tubes, and stored at −80 °C until analysis. In addition to the initial blood sample collected at approximately 2 months of age, additional samples were collected at 3, 4, 6, and 12 months of age and were handled in the same manner as for the initial sample. Samples were stored for no more than 12 months before all parameters were analyzed. The samples were sent by overnight courier, packed with icepacks, and were analyzed at the Gastrointestinal Laboratory at Texas A&M University. All serum samples were thawed at room temperature and serum concentrations of each parameter  were measured on the same day.For kittens ≤ 3 months of age, food was withheld for 6 h, while for kittens > 3 months of age food was withheld for 12 h prior to blood collection. Upon enrollment into the study, a total of 3.5 mL of blood was collected from each kitten from the jugular vein, allowed to clot for 30 min, centrifuged at 3000× On each sampling day, a detailed clinical history was obtained, and cats underwent a thorough physical examination, like on enrollment.Feline PLI concentrations were measured by the Spec fPL assay  using a previously validated immunoassay . The refp < 0.05. All statistical analyses were performed using statistical software packages .Data were tested for normality using the Kolmogorov–Smirnov test. Data were not normally distributed; therefore, overtime comparisons were performed with Friedman tests, while Dunn’s post hoc tests were performed to determine which time-points were significantly different. Statistical significance was set at A total of 14 cats completed the 10-month study. Of these, 8 were males and 6 were females. All cats were neutered/castrated by the end of the study period and were tested negative for FeLV antigen, FIV antibodies, and canine parvovirus antigen.p = 0.0168; Serum was available for all time-points for measurement of fPLI concentrations for 12/14 cats, and only these cats were included in the over-time analysis. Two additional cats were missing one time-point each (at 12 months). Overall, there was a statistically significant difference for serum fPLI concentrations over time  and another cat had one time-point missing (at 12 months). No significant differences of serum fTLI concentrations were found over time . In addip = 0.005) from 2  to 3 months of age , and this was followed by a significant increase (p < 0.001) by 12 months of age  and 2 cats had one time-point missing each . Serum cobalamin concentrations significantly decreased . In addition, serum cobalamin concentrations significantly decreased between 2 and 3 months of age, and this was followed by a gradual and significant increase by the age of 1 year. In the only study published so far as a full paper where the relationship between age and serum cobalamin concentrations was investigated, only adult (between 3 and 9 years of age) healthy colony cats were included . In thatIn humans, serum cobalamin concentrations undergo significant changes during development. During early life, serum cobalamin decreases in humans, with the lowest concentrations observed from 6 weeks to 6 months of age, and this is followed by a gradual increase with a peak between 3 and 7 years of age, while a reduction is observed thereafter, which reaches a plateau towards adulthood ,31. SeveThe mechanisms of cobalamin absorption, transport, and metabolism have not been elucidated in cats during early life. In humans, cobalamin is stored in the liver of the fetus during pregnancy, and subsequently, hepatic cobalamin stores play a major role in determining serum cobalamin concentrations during the first months of newborn life ,37. FollDuring infancy in humans, the IF is either not produced in sufficient quantities by the stomach or it is not functional until a certain age ,40,41. ISerum cobalamin concentrations are also known to be affected by the intestinal microbiota . The intMarkers of cellular deficiency of cobalamin, such as serum methylmalonic acid (MMA) concentrations, have been previously investigated in cats ,47,48. MThe main source of cobalamin in cats is considered to be the diet . All catFood was withheld for 6 h in kittens < 3 months of age and for 12 h for kittens > 12 months of age. This was in order to prevent problems such as hypoglycemia, caused by prolonged fasting in kittens of a very young age. However, this is not expected to have influenced our results, because in a recent study it was shown that feeding did not affect serum fPLI and cobalamin concentrations . AlthougOur study had some limitations. The number of cats that completed the study was relatively small. This was a prospective study with a relatively long follow-up period, and it was challenging to engage owners to regularly come back for blood collection. Even with these small numbers, our results were rather consistent in each group, and therefore, they likely reflect the general population.In conclusion, our results indicate that serum fPLI and fTLI concentrations are not significantly affected by age in young kittens, between the ages of 2 and 12 months, and can be used for the investigation of pancreatic diseases in these animals. In contrast, serum cobalamin concentrations are commonly below the established reference interval in kittens. Whether this represents a physiological or a pathological condition is not clear, and further studies are needed to investigate this finding. In any case, an age-specific reference interval for serum cobalamin concentration should be established for kittens. However, given that cobalamin supplementation is not associated with any known side effects, overdiagnosis of hypocobalaminemia in kittens would not be expected to be detrimental.


Important discoveries have characterized the last decade, highlighting the importance of investment in research in fields such as medicine, biology, computer science, and physics ,6,7,8,9.Hybrid nanosystems, in which different components synergistically contribute to peculiar properties, are an important example of how multidisciplinarity is now essential for developing innovative ideas and materials. In particular, the study and development of hybrid materials based on metal nanoparticles and polymers require studies on the structure–property relationships, and will allow advanced applications in sectors such as energy, optoelectronics, and environmental protection ,14,15,16Therefore, this Special Issue was born, collecting contributions from different sectors such as chemistry, engineering, physics, and biology. The great goal achieved with this collection is certainly the ability to provide an updated overview of both the great opportunities and the challenges that hybrid materials based on metal–polymer nanoparticles create.One of the key topics of the last decade concerns the use of silver nanoparticles (AgNPs) and their increasing integration into environmental applications, including the monitoring and treatment of water pollution, which is raising concerns about their environmental impact. The review by Fiorati et al.  analyzes0 particles appeared in the resinous phase as a product of the reduction of the precursor, i.e., copper (I) oxide particles previously deposited in the two support materials. As a result, macroporous and gel-type hybrid products containing ZVC were obtained, with total copper contents of 7.7 and 5.3% by weight, respectively. X-ray diffraction and Fourier-transform infrared spectroscopy (FTIR) confirmed the successful transformation of the starting oxide particles into a metallic deposit. A scanning electron microscopy (SEM) study showed that the morphology of the deposit is mainly influenced by the type of matrix exchanger. Considering that both the reaction parameters and the operating techniques influence the size, shape, and distribution of Cu0, as well as the porous structure of the polymer matrix, the composite materials obtained can have promising applications, including in catalytic or photocatalytic chemical reactions involving both gaseous or liquid reagents, as well as showing antibacterial activity.I. Jacukowicz-Sobala et al.  presenteG. M. Di Salvo et al.  studied 3)2·4H2O was utilized, with water pressure as an external physical force. When the CA was complexed with Cd(NO3)2·4H2O and exposed to external water pressure, the water flux through the CA was observed, indicating the generation of pores in the polymer. Furthermore, as the hydraulic pressure increased, the water flux increased proportionally, indicating the possibility of the control of the porosity and pore size. Surprisingly, the flux value, above 250 LMH (L/m2h), observed at the ratio of 1:0.35 (molar ratio of CA:Cd(NO3)2·4H2O) was higher than the fluxes of CA/other metal nitrate salt (Ni(NO3)2 and Mg(NO3)2) complexes. The higher value indicated that larger and abundant pores were generated in the cellulose acetate at the same water pressure. Thus, it could be postulated that the Cd(NO3)2·4H2O salt played a role as a stronger plasticizer than the other metal nitrate salts such as Ni(NO3)2 and Mg(NO3)2. The coordinative interactions between the CA and Cd(NO3)2·4H2O were investigated by IR spectroscopy. The change in ionic species in Cd(NO3)2·4H2O was analyzed by Raman spectroscopy.W. G. Lee et al.  presente2). The products and semi-components were characterized in terms of their physicochemical properties, such as chemical structure, crystallinity, and swelling degree. The nanoparticles’ and ready biomaterials’ morphologies were investigated by SEM and TEM methods. Finally, the scaffolds were studied for their bioactivity on MG-63 and effects on current-stimulated biomineralization. The obtained results confirmed the preparation of tunable biomimicking matrices that may be used as a promising tool for bone-tissue engineering.Tissue engineering is an area in which biomedical research is investing heavily ,22. Tiss8). After it underwent mechanical deformation, the flexible SERS substrate still maintained high mechanical stability, which was proved by experiments and theory. For practical applications, the prepared flexible SERS substrate was adapted for the in situ Raman detection of adenosine aqueous solution and methylene-blue (MB) molecule detection on the skin of a fish, providing a direct and nondestructive active platform for detection on surfaces with any arbitrary morphology and aqueous solution.M. Wu et al.  introducMagnetic nanoparticles (MNPs) are largely investigated for biomedical applications. However, if not properly designed, MNPs can cause several problems, such as cytotoxicity or hemolysis. J.A. Roacho-Pérez et al.  compared− was excluded and based on which calcium alginate/nanocuprous oxide hybrid materials were prepared by a Ca2+-crosslinking and freeze-drying process. The thermal degradation and combustion behavior of the materials were studied by related characterization techniques using pure calcium alginate for comparison. The results show that the weight loss rate, heat release rate, peak heat release rate, total heat release rate, and specific extinction area of the hybrid materials were remarkably lower than those of pure calcium alginate, and the flame-retardant performance was significantly improved. In fact, nanocuprous oxide formed a dense protective layer of copper oxide, calcium carbonate, and carbon by lowering the initial degradation temperature for the polysaccharide chain during thermal degradation and catalytically dehydrating to char in the combustion process; thereby, it could isolate combustible gases, increase carbon residual rates, and notably reduce heat release and smoke evacuation.At the end of this Special Issue, we have the work of P. Shao et al.  addressiIn conclusion, as the editor of this Special Issue, I am aware that the diversity and innovation of new compounds and tools that are rapidly developing in the field of multidisciplinary research related to nanomaterials based on noble metals cannot all be collected in a single volume. However, I am certain that this collection will contribute to the interest in the research in this area, providing our readers with a broad and updated overview of this topic.


We also assessed lifestyle , respiratory symptoms and health-related quality of life (HRQL) of the personnel using questionnaires. Out of 11,831 5-min data points, daily median respirable PM concentrations were highly variable and ranged from 0.013 to 0.666 mg/m3 with 8.5-times difference in the median concentrations between the venue with the highest median (0.29 mg/m3) and the least median (0.034 mg/m3). In a multivariate linear regression modelling, ambient PM2.5 concentration was the strongest predictor of daily median respirable PM concentration , and R2 of the model was 0.63. We also found a positive association of the median respirable PM with respiratory symptoms and seasonal allergy, but not with HRQL. Short-term respirable PM levels in the beauty salons may be very high, but the median concentrations are mainly determined by the ambient air pollution.We aimed to assess exposure to respirable particulate matter (PM) of beauty salon personnel, identify its determinants and ascertain the associated respiratory effects. We collected 122 full-day respirable PM samples from 12 beauty salons (floor area ranging from 24 to 550 m Occupational exposure to vapors, gases, dusts and fumes via the inhalational route is frequent in a wide range of jobs. Many respiratory diseases, including chronic obstructive pulmonary disease (COPD) are associated with such occupational exposure ; howeverStudies which reveal personal exposure of beauty salon employees to chemicals and particulate matter (PM), generated from various sources, mostly from sprays, are limited. Overexposure to VOCs , formaldConcerns over the health effects of occupational exposure of a hairdresser mostly arise from the use of sprays, which produce aerosols, usually a mixture of many chemicals. The respirable fraction of such aerosola may be of greatest interest because of the associated health effects, demonstrated in a wide range of occupations. While there are a few existing reports on the indoor respirable PM monitoring in the beauty salons, and they show peaks of very high mass concentrations, these studies were limited to a few geographical areas and brands of sprays, solvents and other substances used locally  in additThis study was approved by the Committee on Bioethics of al-Farabi Kazakh National University and was conducted in accordance with the Declaration of Helsinki and all relevant regulations. All study participants signed a written informed consent to participate. For respirable PM monitoring we selected twelve locations in Almaty, the largest city of Kazakhstan, located all over the city and stretching from the northern  to the southern locations (closer to the hills). Selection of locations was dictated mostly by salons’ consent to participate, but we also pursued the need to embrace neighborhoods differing in presumed air pollution, population socioeconomic status and population density. Aerosol monitoring was completed within 10-day periods in each place in order to cover business days and weekends, and to show maximum variation in concentrations resulting from alternating workloads. All the included salons provided service to both males and females and did not have any specific specialization. In addition to respirable PM monitoring, we also asked available personnel to complete the questionnaire.The questionnaire was offered in either Russian or Kazakh to all those willing to participate and consisted of 58 questions. We found no differences in age and sex between the groups of those who agreed and refused to participate. We have reported earlier the outcomes of a population-based study ascertaining occupational profile and the risk of respiratory disease, in which we applied this questionnaire . In brie3, but we also presented the minimum and maximum (peak) concentrations for each day.Because selected salons did not have a fixed work schedule and could operate late into the day and we sampled respirable PM mass concentrations in these places from the time of their opening till their closure, sampling duration differed from day to day. We used a portable, battery-operated monitor SidePak AM520 , which was placed at an elevation of 1.5–1.7 m from the floor in the central part of the main hall. This device used light-scattering photometric technology to measure PM mass concentration. A hose attached to the inlet of the monitor was connected to a Dorr-Olivier cyclone, set to operate at a flow rate of 1.7 L/min. The device was zeroed daily prior to sampling. There was only one device in each sampled venue, and we collected ten full-day samples corresponding to ten consecutive days of monitoring in each place. The monitor was set to log 5-min means of respirable PM, which were treated as data points in our analysis. For a typical 8-h workday, we collected 96 data points of respirable PM mass concentrations. In the subsequent analyses, we computed daily medians from these 5-min points, expressed as mg/mwww.airkaz.org (accessed on 9 January 2023). This resource pools 1-min data from portable sensors situated throughout the city to daily means, from a number of cities in Kazakhstan. We extracted data from all sensors in Almaty  for each day when we collected respirable PM concentrations in the salons, and calculated the means for those days. Because respirable PM concentrations are not measured by these sensors, we only had PM2.5 concentrations available for this analysis.In this study, we did not aim to monitor ambient air concentrations of respirable PM; instead, we used sampling data from a network of portable sensors, integrated into the State Agency on environmental monitoring (Kazhydromet). Data on the daily mean concentrations of PM2.5 were available from the website 3. This concentration was computed from 5-min mean concentrations as data points. First, we tested normality of all data with Shapiro–Wilk test and found that respirable PM mass concentrations along with most other continuous data in the current presentation were non-normally distributed. Therefore, all reported tests in our presentation were nonparametric. For respirable PM concentrations, we present minimum, maximum and median concentrations for each day of sampling. We then compared daily medians (122 days) with each other using the Kruskall–Wallis test. Furthermore, median and geometric mean concentrations were calculated for each of the 12 included salons from daily means in each place (from 10 data points representing daily means). These medians and geometric means for each salon were tested in a Kruskall–Wallis test to assess whether the variance between salons (between-group) exceeded the one within them (within-groups).The primary outcome of this analysis was daily the median respirable PM mass concentration in mg/mIn order to identify predictors of the log-transformed daily indoor median respirable PM concentrations, we applied linear regression modelling, in which we included log-transformed ambient PM2.5 concentrations for a given day, internal square, the mean number of customers a day, weekday (business day vs. weekend) and number of working personnel and reported beta coefficient for these predictors along with their corresponding 95% confidence intervals (CI). None of these predictors were collinear.2 test was used to test difference between two groups. HRQL mean scores were compared to the population means for Almaty [p-values from a Mann–Whitney test. All procedures were completed in NCSS 2021  and p-values below 0.05 were considered significant.Demographic, lifestyle, occupational history, respiratory symptoms and HRQ were described and analyzed assuming normal distribution and thus presented as means with the corresponding standard deviation (SD) in those few cases when data were normally distributed; or, alternatively, they were presented as medians with their corresponding interquartile range (IQR). Binary data distributions are presented as N with their percent from the group, and, whenever applicable, χr Almaty  using th3, with the total staff ranging from 3 to 8 with up to 20 customers a day. Three included venues were located in former apartments, whereas two places were situated in a quite polluted neighborhood, close to a power plant. There were no windows in two salons out of twelve in the study. We obtained data from 12 venues and completed 10 days of monitoring in each place. Monitoring duration ranged from four to twelve hours, depending on the open time in each place. Overall, we collected 11,831 data points, which were 5-min means of measurements, and the location of included venues is shown in 3 , geometric mean 0.083 mg/m3) with severe left skewness (8.40). Of the overall count of 11,831 data points, 5-min mean concentrations exceeding 0.1 mg/m3 were found in 4479 data points (38% of data), exceeding 0.2 mg/m3 in 2218 data points , and exceeding 0.5 mg/m3 in 614 points (5% of the data). Very high concentrations above 1 mg/m3 were recorded in 205 data points, which corresponded to 2% of the overall work time. All further analyses represent grouped daily data (122 days), either median or geometric means. Daily median respirable PM concentrations were highly variable and ranged from 0.013 to 0.666 mg/m3.Measured 5-min mean respirable PM concentrations ranged from 0 to 6.3 mg/m2.5 concentrations. Despite high variance of within-day concentrations, with spikes corresponding to the use of sprays and fans, the overall pattern of concentration changes from day to day followed that of the ambient PM2.5 concentration, suggesting that the latter was a strong predictor of the inside median concentrations. Nevertheless, the highest ambient daily concentration was 0.142 mg/m3, but the highest recorded indoor respirable PM concentration was as high as 6.3 mg/m3. This highest concentration was recorded in the salon number 12 during the intense and simultaneous use of sprays for more than one customer at a timeHigh daily median concentrations were recorded in the cold season only, whereas low daily concentrations were registered in June and July. We found high correlation between daily median (r = 0.83) respirable concentration inside the beauty salons with the mean daily ambient PMp < 0.001, power 100%) (3) and the least median  of all daily median concentrations. In a multivariate linear regression modelling, accounting for the internal floor area, the mean number of customers a day, weekday (business day vs. weekend) and number of working personnel, the ambient PM2.5 concentration was the strongest and most powerful predictor of daily median respirable PM concentration in the salons . This predictor alone explained 51% of the overall variability of the internal respirable PM concentrations  . The gretrations , whereasp < 0.001). In the univariate analyses, testing the association of exposure to respirable PM at work, expressed as either the median of daily means for a given salon, with respiratory symptoms or diagnoses, most associations were non-significant, likely because of the small sample. We found positive association of the median respirable PM with the fourth question of CAT (shortness of breath) and seasonal allergy and negative association with chronic bronchitis  median 1 vs. 0, p < 0.001; CAT question 2 (sputum) median 1 vs. 0, p < 0.01). Moreover, waterpipe use was significantly associated with a higher score on question CAT 2 (sputum). We did not find any associations of cigarette smoking with the diagnoses of chronic bronchitis, COPD, asthma or allergic rhinitis, likely because of the small number of cases.Daily smoking was significantly associated with respiratory symptoms  used and enforced elsewhere. OELs for PM in Kazakhstan have never existed; therefore, compliance with regulations in this study cannot be assessed or documented. For workplaces, local legislation specifies total dust levels for selected workplaces including those with expected high crystalline silica content. Moreover, local legislation does not specify the difference between personal and area sampling. In the current study, we report area sampling, which is an alternative approach to test exposure, when personal sampling is not feasible.The strength of our analysis is a large number of sampling measures and long sampling period, which included cold and warm seasons and was performed daily. However, the limitation is a small sample of workers, which resulted from poor consent to participate and general low interest in research. Another limitation is sampling of one PM fraction and no opportunity to monitor chemical composition of the PM arising from aerosols. In addition, we could not create a log of activities in the salons, which could associate the peaks of respirable PM with the use of sprays. Finally, respiratory presentation of the employees could not be verified for ancillary investigations, including spirometry, X-ray, because the overall compliance was quite poor.In conclusion, this study allowed us to analyze 122 consecutive days of data, obtained from 12 beauty salons in Almaty reflecting real-time respirable PM mass concentrations. We have identified high variability of concentrations both within and between the salons. However, the median concentrations were more dependent on the ambient fine PM pollution, indicative of the enormous burden of ambient air pollution the cities such as Almaty. Although the respiratory health of included employees was quite fair and poorly associated with the median indoor respirable PM concentrations, more effort should be made to protect beauty salon staff from inhalable pollutants. We also call for urgent action for cigarette and waterpipe smoking cessation with the purpose of protecting respiratory and cardiovascular health.


Ultrasound (US) is often used to diagnose liver masses. Ensemble learning has recently been commonly used for image classification, but its detailed methods are not fully optimized. The purpose of this study is to investigate the usefulness and comparison of some ensemble learning and ensemble pruning techniques using multiple convolutional neural network (CNN) trained models for image classification of liver masses in US images. Dataset of the US images were classified into four categories: benign liver tumor (BLT) 6320 images, liver cyst (LCY) 2320 images, metastatic liver cancer (MLC) 9720 images, primary liver cancer (PLC) 7840 images. In this study, 250 test images were randomly selected for each class, for a total of 1000 images, and the remaining images were used as the training. 16 different CNNs were used for training and testing ultrasound images. The ensemble learning used soft voting (SV), weighted average voting (WAV), weighted hard voting (WHV) and stacking (ST). All four types of ensemble learning  showed higher values of accuracy than the single CNN. All four types also showed significantly higher deep learning (DL) performance than ResNeXt101 alone. For image classification of liver masses using US images, ensemble learning improved the performance of DL over a single CNN. Hepatocellular carcinoma (HCC) is the most common primary liver cancer, the sixth most common cancer worldwide, and the second leading cause of cancer death, resulting in almost 800,000 annual deaths worldwide ,2,3. SurThere are published studies of artificial intelligence (AI) in USG, including thyroid, breast, abdomen, pelvic area, obstetrics and gynecology such as fetus, heart and vascular. AI-based image classification of liver masses has been studied in computed tomography (CT) ,13 and aEnsemble learning, which uses multiple learning models, has recently become popular in image classification using DL. The purpose of using ensemble learning is to improve the AI performance by having multiple models cooperate with each other. Conventional ensemble learning related to diagnostic imaging includes studies using voting and stacking methods ,46,47,48The purposes of this study are as follows. (1) To compare the usefulness of several ensemble learning methods using multiple CNN learning models for multiclass image classification of FFLs in US images. (2) To investigate the usefulness of one of the ensemble pruning methods, the ranking method, for multiclass image classification of FFLs in US images.This is a multicenter diagnostic study using the B-mode ultrasound image dataset of FLLs. The inclusion criteria for data collection are as follows: (1) Patients’ FLLs were detected by B-mode US. (2) The diagnosis of the FLLs was confirmed via histology, contrast-enhanced computed tomography (CECT), contrast-enhanced ultrasonography (CEUSG) using Sonazoid, or gadoliniumethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI. In this study, 101,242 B-mode images of FFLs from 30,873 cases were collected from 1 April 2018 to 25 July 2021 in 11 core medical centers through a research project funded by the Japan Agency for Medical Research and Development (AMED), entitled “National Database Construction of Digital Ultrasound Images and Artificial Intelligence-Assisted Ultrasound Diagnostic System Development” . Of theshttps://jp.ubuntu.com/ accessed on 20 November 2022) was used as the software. Programming languages used were python version 3.8 (https://www.python.org/ accessed on 20 November 2022) and tensorflow version 2.8 (https://www.tensorflow.org/ accessed on 20 November 2022), keras version 2.8 (https://keras.io/ accessed on 20 November 2022), a machine learning library, and scikit-learn 0.24 (https://scikit-learn.org accessed on 20 November 2022) were used to create each program.The hardware used was a desktop computer created for AI. The specifications were Intel core i9 CPU, 128 GB random access memory(RAM), and NVIDIA RTX A6000 graphics processing unit (GPU). Ubuntu Linux version 20.04  in this study is as follows.These values can be calculated for each class. The macro-average is the average of these values. The formula for calculating the macro-average of precision  curve and ROC area under the curve (AUC) score are not immediately applicable to a multiclass classifier. One vs. Rest, where each class is compared to the other classes simultaneously, allows drawing ROC curves for multiclass classifiers. 16 CNNs with 4 classes had ROC curves AUCs computed. Macro averages of the AUCs were then also computed for each model ,57. FinaA quantitative measure of the ensemble’s effectiveness is to look at the Pearson’s correlation coefficient (CORR) between classifiers. The CORRs of the estimated labels of 16 CNN classifiers are calculated.Since most of the previous papers ,46,47,48i th classifier.Hard voting is a simple majority voting image classification in which each classifier has one vote. In the case of hard voting, in order to obtain the optimal number of ensemble pruning based on the ranking method described in the next section, using an even number of classifiers may result in a tie number of votes for the four classes, and the same number of votes may make the class determination for image classification impossible. To avoid this situation and improve the performance of ensemble learning, there is a technique called WHV, also known as Weighted Majority Voting, which assigns different weights to each classifier. WHV, weighted majority voting is computed by associating a weight assifier . SV alsoassifier . In SV, In simple unweighted SV, the weight https://lightgbm.readthedocs.io/ accessed on 20 November 2022.) as the meta-learner, which is a newer method of gradient boosting than XGBoost and is expected to have higher performance [https://www.preferred.jp/ja/projects/optuna/ accessed on 20 November 2022), an open-source software framework for automating the optimization of hyperparameters, which is a type of Bayesian optimization. We also fixed the random number seeds in the program to ensure reproducibility when using Optuna with LightGBM.In ST, the 16 CNN models are first trained together as a basic learner to obtain predictions. Then, the individual predictions are treated as the next set of training data and added from another layer called the meta-learner . There aformance ,67  between ResNeXt101 and each of the CNNs ranked 10th through 16th .Referring to The average computation time required to output the results from the test data of each of the 15 ensemble learning methods from top2 to top16 was 4.26 s for Soft Voting, 18 min 7.38 s for Stacking, 13 min 22.23 s for WAV, and WHV was 40 min 55.73 s.In this study, we used the value of accuracy as a metric that is often used to compare multiple models to rank the test results of 16 different CNN models , When coThe type of model chosen to achieve high accuracy may also depend on the type and resolution of the target medical images. Therefore, a simple comparison of other papers on the usefulness of ensemble learning and on subjects that differ from each other is limited. In this study, 16 types were widely selected from inception, resnet, and EfficientNet systems. A quantitative measure of the effectiveness of ensemble is to look at the Pearson’s CORR between classifiers, and it is said that ensemble learning is expected to be effective when Pearson’s CORR is 0.95 or less . The 16 There was no significant difference between RexNeXt101, the CNN with the highest accuracy values, and the CNNs ranked 2nd through 9th in accuracy values. Therefore, ResNeXt101 was adopted as the representative of the single CNN for comparison of test results with ensemble learning. In the comparison of SV, ST, WAV, and WHV, WAV showed the best accuracy. As for ST, even though the gradient boosting method was used as a meta-model, it did not perform as well as SV and WAV, as in the previous paper on ensemble learning using medical images .Ensemble pruning was also performed, and test results were compared between WAV, the best performing of the four ensemble learning methods, and ResNexT101, a single CNN. The results showed that WAV significantly outperformed ResNeXt101 up to WAV6, suggesting that pruning can reduce the number of classifiers that are members of the ensemble learning. However, further research is needed on pruning methods and parameters.In this study, the average computation time with SV was 4.26 s, while WAV took 13 min. Advances in hardware have made faster computation speeds possible, making shorter processing times possible. The results of this study also show that ensemble learning clearly improves accuracy compared to single learning models, and it is expected that ensemble learning will become more popular in the future, as the trend toward improved computation speed is expected to continue.Although very rare, cases of PLC associated with BLT have been reported, and US images have been included in these case reports ,72. It iIn multiclass classification of FLLs using US B-mode images, ensemble learning was shown to improve accuracy and the deep learning performance over a single CNN. It was thought that future research should explore ensemble pruning for medical images such as X-ray, CT and MRI, other than US images, especially to find out how many classifier members are useful in ensemble learning by ranking methods.


P < 0.05). The RAS group increased the relative abundance of Bacteroidota, Proteobacteria, Chloroflexi, Synergistota, and Spirochaetota and decreased the abundance of Firmicutes, Desulfobacterota, Actinobacteriota, and Actinobacteriota at the phylum level (P < 0.05). At the genus level, the ruminal content of the RAS group was significantly enriched for Rikenellaceae_RC9_gut_group and Ruminococcus, while depleted for Prevotella, Christensenellaceae_R-7_group, and NK4A214_group (P < 0.05). A total of 37 metabolites were identified between the RA group and the RAS group, of which 15 metabolites were upregulated and 22 metabolites were downregulated compared with the RA group. Metabolic pathway analyses indicated that upregulated the metabolites of the RAS group yak calves were related to carbohydrate metabolism, ubiquinone, and other terpenoid-quinone biosynthesis, while the downregulated metabolic pathway was relevant to xenobiotic biodegradation, metabolism, and nucleotide metabolism. In summary, starter feeding before weaning significantly increased the dry matter intake and body weight of yak calves, changed the diversity and abundance of ruminal microbiota, and positively regulated the good development of ruminal morphology and function, providing an important basis for high-quality cultivation and the nutritional level of nutrition of yak calves in the Qinghai Tibet plateau. This study is based on the availability of 16S rRNA sequencing and LC-MS-based metabolomics in clarifying the function of starter feeding in the yak calves.For young ruminants, starter feeding can effectively facilitate the growth and development of rumen in ruminants, but the development of rumen is an important physiological challenge as it remains unclear for the mechanism of starter feeding stimulating. In this study, we performed an analysis of ruminal microbiota and their metabolites in yak calves to explore how the ruminal microbiota and their metabolites stimulate the ruminal function. This study associated 16S rRNA sequencing with liquid chromatography-mass spectrometry (LC-MS)-based metabolomics to evaluate the effects of starter feeding on ruminal microbiota diversity and metabolites in yak calves. We designed the experiment using 20 yak calves that were assigned equally into 2 groups, based on feeding milk replacer; the control (RA) group was fed with alfalfa hay while the treatment (RAS) group was fed with alfalfa hay and starter. After the experiment, we investigated the ruminal microbiota and metabolites through 16S rRNA sequencing and LC-MS-based metabolomics. During the preweaning period, the RAS group significantly promoted the growth performance and ruminal development in yak calves, including increases in body weight, chest girth, and development of rumen ( Yak calves are the foundation of the yak industry in the Qinghai-Tibetan Plateau, and the quality of yak calf rearing directly contributes to the performance of adults . In the The digestive tract mainly develops in the early growth stage of calves, which effectively influences their long-term performance . As the Although it had already been proved in dairy calves that alfalfa hay could promote ruminal epithelial and muscular development , but thevia 16S rRNA sequencing) has been used to assess the influences of dietary on the ruminal microbial community .All the yak calves were maternally nursed and grazed in the Datong Yak Breeding Farm of Qinghai Province before the trail. The experiment was conducted from July to November 2020, with 20 male yak calves at the age of 30 days  with similar body conditions randomly recruited and assigned into two groups, with ten calves per group, nursed at the Haibei Tibetan Autonomous Prefecture Plateau Ecological Animal Husbandry Science Park Management Committee. All the calves were supplied with the same milk replacer ; while the control (RA) group received only alfalfa hay, the treatment (RAS) group was fed with alfalfa hay and starter . The ten calves in each group were individually fed in ten different pens. We fed all the yak calves twice a day, at 08:00 and 16:30 with 100–700 g of milk replacer powder dissolved in 42°C water five times. The supplementation of milk replacer increased along with the increase of body weight, approximately 80 g per week until 3 months of age, and then gradually decreased by the same rate until the end of the study. Freshwater was supplied freely to the yak calves.In brief, during the experimental period, the alfalfa hay and starter offered were adjusted daily to ensure at least 10% orts, while daily feed supplied was recorded at 3-day intervals, and the orts were gathered as well and then pooled and weighed at 3-day intervals for the calculation of the averaged dry matter intake (DMI) over 3 days until the average daily DMI achieved 1 kg each of the yak calves. At the end of the experiment, this resulted in the numbers of the feed intakes for each calf, and the means of those intakes were used as individual replicates for the statistical analysis of the difference in feed intake between the two treatments.Samples of the starter feed, alfalfa hay, and milk replacer were measured  for dry When the average daily DMI achieved 1 kg each of the yak calves, yak calves were fasted for 24 h, and then, the body weight, height, length, and the chest girth of all the yak calves were recorded. Five yak calves were selected randomly from each group, killed by exsanguination, and then dissected at once.3-N analyses. Specifically, a solute with metaphosphoric acid and crotonic acid was added to 2 ml of these 5 ml ruminal fluid samples before further analyses of the VFA concentrations in gas chromatography  . Meanwhile, another 5 ml of the ruminal fluid was collected and stored at −20°C for VFA and NH, Japan) .Subsequently, three segments of the tissue sample (2 × 2 cm) from the ventral sac of the rumen were collected, immediately washed with saline solution, then fixed in 10% buffered formalin, and stored at 4°C until papilla length and width, and the thickness of ruminal base was measured . All theBy using the routine method of the wax section, the development of rumen was studied. After fixing in 10% buffered formalin for 24 h, the ventral sac of the ruminal tissue samples was gradually dehydrated at different concentrations  of ethanol and cleaned. Then, the ruminal samples were trimmed into small pieces and inserted into cassettes, which were embedded in liquid paraffin. Notably, 5-μm paraffin sections were sliced using the microtome and stained with hematoxylin-eosin. Using the phase-contrast microscope  the papillae length and width of the ruminal tissue and the thickness of the ruminal base were measured .g for 10 min at 4°C before the VFA and NH3-N concentration measurement. Using the Agilent 6850 gas chromatograph  equipped with a polar capillary column  and a flame ionization detector to analyze the supernatant ruminal fluid samples is previously described .The ruminal fluid samples were centrifuged at 13,000 × escribed . The NH3Total genome DNA from the 10 ruminal content samples of yak calves from two different treatments was extracted using the cetyltrimethylammonium bromide (CTAB) method in accordance with ® High-Fidelity PCR Master Mix , 2 μM of forward and reverse primers, and approximately 10 ng template DNA. Thermal cycling consisted of initial denaturation at 98°C for 1 min, followed by 30 cycles of denaturation at 98°C for 10 s, annealing at 50°C for 30 s, and elongation at 72°C for 30 s, and finally, 5 min at 72°C. PCR product quantification and qualification: the same volume of 1 × loading buffer (contained SYB green) was mixed with PCR products and electrophoresis on 2% agarose gel was performed for detection. PCR products were mixed in equidensity ratios. Then, the mixture of PCR products was purified using the Qiagen Gel Extraction Kit . Sequencing libraries were generated using the TruSeq® DNA PCR-Free Sample Preparation Kit  following the manufacturer’s recommendations and adding index codes. The library quality was assessed using the Qubit@ 2.0 Fluorometer  and Agilent Bioanalyzer 2100 system. Finally, the library was sequenced on an Illumina NovaSeq platform, and 250 bp paired-end reads were generated.16S rRNA genes of 16S V3-V4 regions were amplified using specific primer set 515F (5′-GTGCCAGCMGCCGCGG-3′) and 806R (5′-GGACTACNNGGGTATCTAAT-3′) with barcodes . All PCRQuality filtering on the raw tags was performed under specific filtering conditions to obtain the high-quality clean tags , accordiSequence analyses were performed using Uparse software (Uparse version 7.0.1001) . SequencP-value was set as <0.05, and the threshold of the linear discriminant analysis (LDA) score was set at a default value of 2.0.The taxon abundance for each sample was determined according to phylum, class, order, family, and genus. The microbiota were compared for beta diversity using the distance matrices generated from weighted UniFrac analysis, principal coordinated analysis (PCoA), and analysis of similarities (ANOMIS). The g, 4°C for 15 min. Some supernatant was diluted to the final concentration containing 53% methanol by LC-MS grade water. The samples were subsequently transferred to a fresh Eppendorf tube and then centrifuged at 15,000 g, 4°C for 15 min. Finally, the supernatant was injected into the LC-MS system analysis.The ruminal content samples (1 ml) were freeze-dried and resuspended with prechilled 80% methanol and 0.1% formic acid using a good vortex. Then, the samples were incubated on ice for 5 min and centrifuged at 15,000 Discoverer 3.1  was used to perform peak alignment, peak picking, and quantitation for each metabolite. Later, peak intensities were normalized to the total spectral intensity. The normalized data were used to predict the molecular formula based on additive ions, molecular ion peaks, and fragment ions. Then, peaks were matched using the mzClou, mzVault, and MassList database to obtain accurate qualitative and relative quantitative results.Statistical analyses were performed using the statistical software R (R version R-3.4.3), Python (Python 2.7.6 version), and CentOS (CentOS release 6.6). When data were not normally distributed, normal transformations were attempted using area normalization.t-test) to calculate the statistical significance . The metabolites with VIP > 1, P-value < 0.05, and fold change (FC) ≥ 2 or FC ≤ 0.5 were considered to be differential metabolites. Volcano plots were used to filter metabolites of interest-based on log2(FC) and −log10 of metabolites using ggplot2 in R language.These metabolites were annotated using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Principal component analysis (PCA) was performed at metaX   with replicates as experiment units, and a value of P < 0.05 was regarded as statistically significant. The differences in DMI between two groups of yak calves were further analyzed using the following model: Yij = μ + Di + Tj + εij + DT, using the MIXED procedure of SAS , which considered the significant differences of these indices induced by the time effect in the same treatment. Yij is the response variable, in particular, μ is the overall mean, Di is the fixed effect of treatment , Tj is the fixed effect of time (10 days as a unit) of the experiment, DT is the interaction of dietary and time, and εij is the residual error. If a significant diet and time effect were observed, the significance between the treatment and time differences was separately identified using the Tukey’s test multiple comparison test. All data are expressed as the means with the standard error.In this study, all data were tested and presented as a normal distribution. At the beginning of the experiment, the initial body weight, height, length, and chest girth were tested using the P ≤ 0.05).The statistical evaluation of 16S rRNA sequencing and the untargeted metabolomics results were analyzed using the bioinformatics methods described above. Spearman’s correlation test was used to examine relationships between the RA group and the RAS group. The correlation coefficient rho between the relative abundance of differential metabolites and the total abundance of differential bacteria was calculated using the Spearman statistical method , where the higher intake was found for yak calves in the RAS group. Compared with the RA group, the RAS group had a significantly greater body weight (P < 0.001), height (P = 0.008), and chest girth (P < 0.001) (P = 0.036)  . Meanwhi= 0.036) .P = 0.049). The RAS group could significantly increase the ruminal fluid NH3-N concentration compared with the RA group (P = 0.001). Besides, the RA group had a significantly higher acetate concentration than the yak calves in the RAS group (P = 0.034), while the valerate concentration was significantly greater in the RAS group (P = 0.021)  .P = 0.046), whereas the two groups showed no significant difference in Chao 1 value, Shannon indices, and Simpson index (P = 0.468). Moreover, beta diversity analyses showed that the compositions of the gastrointestinal prokaryotic community of the yak calves in different feeding groups were different in the rumen , Desulfobacterota (P = 0.002), and Actinobacteriota (P = 0.002) were significantly greater in the RA group, while Bacteroidota (P = 0.001), Proteobacteria (P = 0.011), Chloroflexi (P = 0.004), Synergistota (P = 0.005), and Spirochaetota (P = 0.017) were significantly higher in the RAS group (Prevotella (P = 0.018), Christensenellaceae_R-7_group (P = 0.013), and NK4A214_group (P = 0.018) were significantly greater in the RA group. Rikenellaceae_RC9_gut_group (P = 0.004) and Ruminococcus (P = 0.041) were identified significantly greater genera in the RAS group. Furthermore, similar results that contained similar but less differential bacteria were also identified using the Mann–Whitney U test , indicating that the test process was stable and the quality of data high (Based on the relative quantitative value of the metabolites, the Spearman correlation coefficient between the QC samples is calculated . The corata high .In contrast, metabolism mainly participated in amino acid metabolism and nucleotide metabolism in ruminal content . We deteAs shown in There is an interaction between ruminal microbiota and growth performance of yak calves and ruminal fermentation profiles, which affects the feed efficiency and tissue development of ruminants. The correlation between them is illustrated in Actinobacteriota, unidentified-Archaea, and Cyanobacteria. The DMI of yak calves was significantly negatively correlated with Bacteroidota, unidentified-Archaea, and Cyanobacteria. The ruminal weight of yak calves was significantly negatively correlated with Verrucomicrobiota, unidentified-Archaea, MBNT15, Sva0485, Cyanobacteria, and Nitrospinota. The width of ruminal papilla was significantly negatively correlated with Spirochaetota. The length of ruminal papilla was significantly positively correlated with Proteobacteria, unidentified-Bacteria, and Kapabacteria and significantly negatively correlated with Bacteroidota and unidentified-Archaea. The NH3-N concentration in the ruminal fluid was significantly negatively correlated with the Bacteroidota, unidentified-Archaea, and Verrucomicrobiota and was significantly positively correlated with Desulfobacterota and Kapabacteria. The MCP concentration in the ruminal fluid was significantly negatively correlated with the relative abundance of unidentified-Archaea and Cyanobacteria. Acetate concentration was significantly positively correlated with Verrucomicrobiota and unidentified-Archaea and significantly negatively correlated with Kapabacteria. Propionate concentration was significantly positively correlated with Chloroflexi. The concentration of valerate was significantly negatively correlated with Bacteroidota, unidentified-Archaea, MBNT15, Sva0485, and Cyanobacteria. TVFA concentration was significantly positively correlated with Cyanobacteria.At the phylum level , finally3-N, MCP concentration, and valerate concentration and the relative abundance of Ruminococcus, significant negative correlations between acetate and TVFA concentration and the relative abundance of Ruminococcus. MCP and valerate concentrations were significantly positively correlated with Sharpea. Butyrate concentration was significantly positively correlated with the Prevotaceae-UCG-001. The concentration of acetate was significantly negatively correlated with Ruminobacter. The final body weight, DMI, ruminal weight, ruminal papilla length, NH3-N, and MCP concentration and valerate concentration of yak calves were significantly negatively correlated with Lachnospiraceae-XPB1014-group.At the genus level , there wDesulfobacterota and Actinobacteriota. UPM was significantly positive with Firmicutes and Sva0485, while significantly negative with Bacteroidota. Xylitol was significantly positive with Spirochaetota.In this study, the correlation analysis results of metabolites and 16S rRNA are shown. As shown in Rikenellaceae_RC9_gut_group significantly positive with UPM and significantly positive with xylitol. Prevotella, NK4A214_group, Lachnospiraceae_NK3A20_group, Desulfovibrio, Butyrivibrio, and Methanosphaera were significantly positive with Hydroquinone, while Succiniclasticum was significantly negative with Hydroquinone. Delta-tocopherol was significantly positive with Succiniclasticum, Sharpea, Ruminococcus, and UCG-002, while it was significantly negative with Christensenellaceae_R-7_group. UMP was significantly positive with Acetitomaculum and UCG-002.There were 104 significantly positive and 19 significantly negative correlations between ruminal microbiota and their metabolites at the genus level , with RiDue to the slow development of rumen, the growth performance of newborn calves was related to the digestion of wrinkles and the intestine. The ruminal epithelium is responsible for nutrient absorption and transportation in the rumen. This study shows that starter feeding with alfalfa hay significantly increased DMI, body weight, and chest girth in yak calves, which presumably stimulated both the development of ruminal epithelia and performance , in line3-N concentration compared with the RA group, which fed with only alfalfa hay. NH3-N concentration in the rumen is in a dynamic balance, which can provide raw materials for generating the microbial protein (3-N concentration in RAS group yak calves, this is in line with this study (Due to various in-nutrient supplementation, significant changes occurred in the ruminal fermentation, which represented the increased carbohydrate fermentation in the rumen . The sta protein . Increasis study . As suggis study , the alfis study . The sigis study .Bacteroidetes and Firmicutes are the most dominant phylum in yak calves’ rumen, which are consistent with the previous studies on ruminants (Firmicutes vs. Bacteroidetes in the rumen resulted in increasing lignocellulose digestion (Euryarchaeota and Proteobacteria. Through the correlation analysis, Proteobacteria and Synergistota were significantly positive with the NH3-N concentration, and these three indicators were also significantly higher in the starter feeding group, which indicated that starter feeding can promote ruminal microbiota to produce available NH3-N and strengthen the absorption and utilization of nutrients. Proteobacteria have the function of degrading soluble carbohydrates; the crude protein and ether extract were much higher in the feeding of the RAS group, along with the significantly increased abundance of Proteobacteria in the RAS group. Therefore, we predicted that the abundance of Proteobacteria was positive with the crude protein and ether extract content in the dairy feed.Both dietary and additives could influence the abundance of ruminal microbiota , while tuminants . The depigestion . Similarigestion , the domPrevotella was the dominant genus of abundance, which had the ability to degrade fiber sources (Prevotella in the ruminal microbial community have been reported to play an important role in the utilization of dietary nutrition (Prevotella was significantly negative with isobutyrate, and the abundance of Prevotella was significantly increased in the RA group, due to the higher neutral detergent fiber and acid detergent fiber level in the alfalfa hay. Part strains of Butyrivibrio degraded cellulose in the rumen, which also shows that the abundance of Butyrivibrio increased in the RA group. The abundance of Rikenellaceae_RC9_gut_group was significantly enriched in the RAS group and positive with the NH3-N and valerate concentration, which was consistent with the result of rumen fermentation. The relative abundance of UCG-002 was negative with the propionate, butyrate, valerate, and isovalerate concentration, which could be resistant to the growth performance when propionate was absorbed and converted to glucose, amino acids, and lipids ( sources . Membersutrition . In thisd lipids . Very feIn brief, the colonization of ruminal microbiota during preweaning could further influence the subsequent ruminal microbiota of adult ruminants . SpecifiThe alteration in the ruminal metabolites we discovered as a result of feeding starter was not surprising since alteration of the ruminal microbial community generally affects the types of compounds produced by the rumen microbiota. We identified 37 different metabolites using the currently available metabolite databases.t-test and FC analysis, nine pathways were revealed: chlorocyclohexane and chlorobenzene degradation, benzoate degradation, pentose and glucuronate interconversions, aminobenzoate degradation, ubiquinone, and other terpenoid-quinone biosynthesis, ABC transporters, tyrosine metabolism, pyrimidine metabolism, and microbial metabolism in diverse environment pathways. All relevant pathways were significantly upregulated in the starter feeding group due to increased concentrations of the associated metabolites xylitol and delta-tocopherol and decreased UMP and hydroquinone. This study has found that ruminants can meet up to 70% of their energy requirements and 50–70% of their protein requirements through rumen microbial metabolic activities (Ruminal metabolites in pathway analysis expressed the difference in yak calves, and based on the tivities . Xylitoltivities . In the tivities . In thistivities . In feedtivities . In thisBacteroidota significantly decreased with the increase of DMI and showed a positive correlation with Proteobacteria. Bacteroidota, as fiber-degrading bacteria (Proteobacteria can use polysaccharides as a nutrient source for ruminants (Proteobacteria, which may be due to the increased Proteobacteria abundance after starter feeding supplementation, which improves nutrient utilization efficiency of yak calves, promotes ruminal papilla development of yak calves, and thus improves production performance. Studies have shown that Ruminococcus, as a producer of carbohydrate-active enzymes (3-N, MCP, and valerate in the rumen were proportional to the relative abundance of Ruminococcus, suggesting that starter feeding may improve the relative abundance of Ruminococcus and lead to the improvement of body growth performance.The relative abundance of bacteria , were siuminants , ruminal enzymes , can dec enzymes . The finBacteroidota in the rumen, and negatively correlated with Firmicutes. In the 16s rRNA sequencing, the relative abundance of Bacteroidota in yak calves fed with starter feeding significantly decreased, and the difference metabolite UMP significantly decreased, and the trend was consistent. In the functional analysis of differential metabolites, UMP was involved in the metabolism of pyrimidine in the nucleotide metabolic pathway. At the genus level, delta-tocopherol was significantly positively correlated with Ruminococcus and Sharpea, while the Ruminococcus was significantly increased after the yak calves were fed with starter feeding, and the metabolite delta-tocopherol was also significantly upregulated, which promoted the metabolism of coenzyme factors and vitamins. Therefore, UMP and delta-tocopherol can be used as potential markers for exploring the dominant ruminal microbiota. Studies have shown that the correlation between ruminal microbiota and metabolomics plays an important role in the treatment of ruminant ruminal acidosis and other diseases, and there is a direct or indirect correlation between microbiota candidate metabolomics (Ruminal microbial interaction can decompose carbohydrate carbohydrates such as starch and fructose in the diet that cannot be directly absorbed by the digestive tract into monosaccharides or disaccharides. After microbial fermentation, glycogen is resynthesized and then transported to the intestine for decomposition and utilization in the small intestine, which is one of the important pathways for body function . In rumibolomics . Wang chbolomics . Pickardbolomics . How rumThe untargeted metabolomics approach depends on comparing peak intensity to evaluate differences in the relative abundance of metabolites with the disadvantage of a lack of accuracy and precision . FurtherIn summary, a supplement to the starter promoted organ development and increased the abundance of some amylolytic bacteria. Ruminal microbiota have positive associations with metabolites involved in carbohydrate metabolism, nucleotide metabolism, xenobiotic biodegradation, and metabolism, demonstrating that the starter feeding can improve the nutritional status of the yak calves.https://dataview.ncbi.nlm.nih.gov/object/PRJNA808822, BioProject: PRJNA808822.The original contributions presented in the study are publicly available. These data can be found here: The animal study was reviewed and approved by the Animal Ethics Committee of College of Agriculture and Animal Husbandry in Qinghai University. Written informed consent was obtained from the owners for the participation of their animals in this study.YW, SL, and ZC conceived and designed the experiments. YW, ZC, SL, HX, QY, and DY mainly performed the experiments. YW and ZC analyzed the data. ZC and SL contributed the reagents, materials, and analysis tools, had primary responsibility for final content. YW and ZC wrote the manuscript. All authors read and approved the final manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


A total of 28 (78%) were on night shifts. The WAI score was quite low in 5 (13.8%) cases, moderate in 10 (27.7%) cases, good in 14 (38.8%) cases, and excellent in 7 (19.5%) HCWs. Among all health figures, in nurses as well as technical staff, lower WAI scores were observed. HCWs reported various comorbidities, which affected WAI score, such as limited mobility in the upper limbs, arm/shoulder pain, numbness, and lymphoedema. The main complication that negatively affects any work activity is the morbidity in the upper limbs. This seems to affect the ability to perform tasks, and the re-entry to work is highlighted on sick leave days.Breast cancer (BrC) treatment can produce disabilities that often impact the quality of daily life and impact the social and working relationships of the patient. This paper looked into the remaining work ability in a group of female healthcare personnel (HCPs) with BrC in Southern Italy. Each HCP was subjected to a medical check, routine blood tests, and a questionnaire on the work ability index (WAI). Of 980 (100%) HCWs undergoing health control, 6% ( Breast cancer (BrC) is one of the most widespread health issues worldwide ,2, coverIt is also known as the second cause of death in developed countries and the third main cause of death in less developed countries . In 2019Early BrC is considered potentially treatable. Therapy progressed remarkably in the last few years, with less ICUs occupied, both for locoregional and systemic therapy; avoiding overtreatment, but also undertreatment, is often preferred as a protocol choice . BrC is Several factors affect the BrC incidence: lifestyle; increased life expectancy; changes in reproductive patterns; increasing obesity; the socio-cultural impact; and improved early diagnosis, mainly due to efficient screening protocols ,6,7,8,9.Several occupational risk factors are recognized for BrC, and these are often present in healthcare facilities: ionizing radiation, ethylene oxide, and shift/night/work ,16,17,18According to the scientific population, correlations exist between night shift work and an increased incidence of BrC ,20. IndeBrC therapy frequently means surgical treatment combined with chemo- and radio-therapy . These lSeveral surveys already pinpointed that BrC women patients in lower working classes need longer resting periods from work and show a greater loss of working skills ,32.The present study explored the remaining work ability in a set of female healthcare personnel (HCPs) with BrC in Southern Italy.This retrospective case control study was carried out in 2019–2020 and involved previously (in the last 20 years) BrC-diagnosed female HCPs operating at a hospital in Southern Italy.Exclusion criteria were: being affected by other systemic pathologies, such as cardiovascular, metabolic disease, and not being retired. HCPs invited to participate in the present study were informed about aims and procedures. Subjects voluntarily adhered to the study by signing an informed consent. The study was directed in line with Helsinki Declaration guidelines and while the occupational physician was performing his/her duty according to the Italian law decree 81/2008 ,34.For each participant, family, medical, and work histories were carefully carried out to highlight any work-related exposure that potentially fostered the onset of cancer. We investigated demographic factors and lifestyle-related risk elements of each participant, and the activities they participated in during their spare time were also taken into account.Furthermore, the oncology agenda was asked of each participant, updated to the latest treatment, as well as the latest checks performed, such as the genetic, histological, and diagnostic imaging tests ,35. DuriEach participant was subjected to medical check, routine lab tests, and a questionnaire on their work ability index (WAI) . The WAI is an index used to evaluate an operator’s individual work ability so as to establish working skills according to age, pathologies, etc. . The calA control group of HCPs, in the same hospital, was arranged for anthropometrical characteristics, job career, workplace, and habits. The control group consisted of women without previous BrC diagnosis and still in service. The exclusion criteria were the same as the observational group. 2) or Fisher’s exact test, and Student’s t-test. The suitable relationship measures were assessed through the odds ratio . The significant variables of the univariate analysis and logistic regression models were used. The variables were considered statistically significant when p < 0.05. Statistical study was carried out with SPSS software .The collected data were included in a bespoke database. Descriptive statistics were carried out to describe the sample of the study. Data were tested for normality with the Kolmogorov–Smirnov test. All variables were not normally distributed. The association between the different variables was analyzed with the chi-square test (XOut of the 980 (100%), HCPs being health checked in 2019–2020, 54 (5.5%) suffered from BrC (inclusion criteria). BrC identifies were set in the 2002–2019 period. A total of 36 of these 54 HCPs (66.6%) agreed to take part in the study. Out of the 18 HCWs who did not belong in the study, 11 (61%) refused for work for reasons that are due to lack of time, and 7 (39%) did not want to retrace a dramatic episode in their lives see .Participants were, on average, 52.9 ± 7.3 years old, with a service duration of 26.2 ± 7.4 yrs. The BMI average was 25.3 ± 4.8, equivalent to obesity. Most of the participants were nurses in both groups. Five HCPs (13.5%) were still in the fertile period; among controls there were four (11.3%) in the fertile period. The average number of children was 2.04 ± 0.55 in cases and 2.22 ± 1.31 in the control group. The sample characteristics are described in There resulted a statistically significant difference between the cases and the controls in the family history for BrC and the hormone therapy. When diagnosed, the HPCs’ mean age was about 45 years, and the mean service career was 17 years. Most cases were shift workers, including night workers, and most of them used oral birth control devices.The workplace risk assessment identified the following health risks for cases: 36 (100%) biological risk; 13 (36%) video display units; 21 (58%) hand lifting of patients/load; and 28 (78%) night shift work. Anyone was exposed to chemical carcinogens, by their knowledge.Studying the risks, only a significant correlation with night shift work was found: OR = 1.51, CI 95% (1.47–1.56).The investigation of health records concerning BrC exhibited that the majority of cases had BrC histologically classified as Luminal-A (ER+ and/or PgR +HER2−).Luminal-A type, quadrantectomy, lymphadenectomy, chemotherapy, and radiotherapy prevail in cases of BrC. According to the tumor–nodes–metastasis (TNM) classification , stages Only 14 (38.8%) cases had a follow-up with periodic checks every 6 months; 19 HCWs (53%) had BrC over 5 years before and were currently under screening protocols. When the questionnaire was given, one case was under chemotherapy again, with distant lymph node and bone metastases.All 36 (100%) cases had gone back to work. The mean number of days of absence from work was 155.8 ± 205.4 days for nurses/technicians, compared to 128.2 ± 239.7 days for doctors/biologists. Comparing the return to work of nurses/technicians with medical/biologists, the first required an average longer time, but not statistically significant, compared to the latter.WAI average score was good in cases with BrC (37.16 ± 7.6), but lower than those with the control group (38.2 ± 7.7). n = 10) had a lower WAI score than those who had a quadrantectomy (n = 26); moreover, only 4 (12%) HCPs were treated with quadrantectomy and underwent radiotherapy. The results of the WAI score of the last group were greater than 50% of the total values. Furthermore, the subjects undergoing quadrantectomy + chemo/radiotherapy had a higher WAI score than those who had the mastectomy + chemo/radiotherapy. HCPs who underwent lymphadenectomy in addition to the main surgical treatment showed WAI scores less than 50% of the values.From the data analysis, it is observed that HCPs who underwent mastectomy  led to a huge presence of side effects that affected the working ability. The type of treatment received, surgery, radiotherapy, chemotherapy, and hormone therapy, significantly affected recovery times and their going back to work; according to Gregorowitsch et al., (2019), patients reported a severely reduced working capacity during BrC treatment and further reduced when undergoing chemotherapy or lymphadenectomy ,46. It tLimited mobility in the upper limbs, arm/shoulder pain, numbness, and lymphoedema are the main comorbidities detectable after therapy ,48. Theyn = 16) undergoing lymphadenectomy, with a negative impact on everyday life activities, as well the psychological sphere and their working activities. Morbidity in the upper limbs is one of the main complications that can negatively impact working activity, the psychosocial sphere, and generally the quality of life [Limited mobility in the upper limbs, arm/shoulder pain, numbness, and lymphoedema are the main comorbidities reported by the HCPs ( of life ,50 of woSince our participants fell in the economically active domain, an early return, apart from helping the recovery of the worker’s health conditions, would further aggravate her workability.About half of our cases had a stage of cancer 0–1 at diagnosis time. We may deduce this is the result of important screening protocols that, over the years, allowed us to realize a diagnosis of the pathology at an increasingly earlier stage. We know that the work ability of cancer patients is severely impaired in the first months after the first day of sick leave, but it significantly improves in the following months. Self-assessed work ability after 6 months proved to be a strong predictor of later return to work in cancer survivors independently of age and therapy .Scientific data suggest that a multidisciplinary approach is to be preferred. Occupational health doctors should take note of individual and collective risk assessments, promote a healthy lifestyle before and after sick leave, as well propose rehabilitation and solutions to improve the interactions between employees and the work milieu ,52,53. Encouraging patients with low-stage diagnoses to return to work would be advisable, enhancing their quality of life and reducing days of sick leave and requests for disability pension. High-stage patients might take more time to recover from chemotherapy; however, they should be encouraged if their general condition allows for it ,26,54. The strengths of the study were having made a contribution regarding the type of treatment and WAI. The study costs were very low, so the study can be reproduced on any operational context without spending problems.The weaknesses of the research were the sample size, as it was small and consisted mainly of well-educated people. Only a questionnaire was used to assess work ability. Only Caucasian women, predominately well-educated, were present in the sample. However, the results provide initial evidence of a relationship between BrC and shift work. Future studies should include larger and more diverse samples.In conclusion, the type of treatment received, surgery, radiotherapy, chemotherapy, and hormone therapy, significantly affected the recovery times of patients and their going back to work. The relationship between shift work, including night work, and BrC inception is confirmed also by this study. Additionally, it is important to return to work as soon as possible, as for the worker it means a return to normal life and social reintegration. Occupational physicians can improve their key role at the workplace and in society . Early d


The coronavirus 2019 (COVID-19) pandemic has led to a high rate of infections, frequent outbreaks, and high mortality rates in nursing homes (NH) worldwide. To protect and improve the treatment and care of the vulnerable NH population, it is pivotal to systematise and synthesise data from cases of COVID-19 among NH residents. In our systematic review, we therefore aimed to describe the clinical expressions, characteristics, and treatments of NH residents confirmed to have COVID-19.Mweighted), was calculated to account for the large variation in sample sizes of the studies, and due to heterogeneity among the studies, we report our findings in a narrative synthesis.We conducted two comprehensive literature searches in several electronic databases: (1) PubMed, (2) CINAHL, (3) AgeLine, (4) Embase, and (5) PsycINFO in April and July 2021. Of the 438 articles screened, 19 were included in our sample, and we used the Newcastle–Ottawa Assessment Scale to assess the quality of the reported studies. A weighted mean (Mweighted), common symptoms and signs in NH residents confirmed to have COVID-19 were fever (53.7%), cough (56.5%), hypoxia (32.3%), and delirium or confusion (31.2%). Common comorbidities were hypertension (78.6%), dementia or cognitive impairment (55.3%), and cardiovascular diseases (52.0%). Six studies presented data concerning medical and pharmacological treatments, such as inhalers, oxygen supplementation, anticoagulation, and parenteral/enteral fluids or nutrition. The treatments were used to improve outcomes, as part of palliative care, or as end-of-life treatment. Transfers to hospital for NH residents with confirmed COVID-19 were reported in six of the included studies, and the rate of hospital transfers ranged from 6.9% to 50% in this population. In the 17 studies reporting mortality, 40.2% of the NH residents died during the studies’ observation periods.According to the mean weights (Our systematic review allowed us to summarise important clinical findings about COVID-19 among NH residents and to identify the population’s risk factors for serious illness and death caused by the disease. However, the treatment and care of NH residents with severe COVID-19 warrant further investigation. Following the first known outbreak of an unknown virus in December 2019, the virus was identified in January 2020 as a novel coronavirus, namely severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2), and in March 2020, the World Health Organization (WHO) declared the viral outbreak to be a pandemic . Major rNursing homes (NH), as institutions primarily serving older adults who need 24-h health and care services, host a vulnerable, clinically complex population characterised by both physical and mental multimorbidity and decreased function in activities of daily living –8. StudiThe COVID-19 pandemic hit NHs worldwide especially hard and included frequent outbreaks and high mortality rates , 13. To NH residents are particularly vulnerable to outbreaks of infectious disease compared with other populations given their combination of physical and mental multimorbidity, old age, immunosenescence, low functioning in activities of daily living (ADL), increased frailty, high dependence on nursing staff, and the fact that they cohabitate in grouped living environments , 8, 14. Only a limited number of systematic reviews pertaining to the topic of NH residents and COVID-19 have been published. Worth mentioning is the study by Hashan et al.  who condOur review was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement .In our sample, we included all articles reporting primary quantitative studies relevant to the clinical expressions, characteristics and treatments of confirmed cases of COVID-19 among NH residents. Studies written in languages other than English, Norwegian, Danish, or Swedish were excluded.In this systematic review we use the term “nursing home” as a label for the institutions in the articles included in our study. We acknowledge that different interpretations of the term “nursing home” in the different countries can be found, but in this systematic review the term is used for institutions run by health care professionals serving older adults who need 24-h health and care services. Sanford et al. (2015) offers a definition of NHs that states that NHs are facilities “that provides 24-h functional support and care for persons who require assistance with ADLs and who often have complex health needs and increased vulnerability” . The insTwo comprehensive searches for literature in different electronic databases were conducted using combined search terms related to “COVID-19” and “nursing home”. The first search for literature, conducted on 22 April 2021, probed the databases PubMed, CINAHL, and AgeLine, whereas the second, conducted on 5 July 2021, probed those three databases in addition to the EMBASE and PsycINFO databases. The search terms used in the second search differed somewhat for the various databases, as presented in the search log in Table n = 438) were screened. The de-duplication process was conducted by a principal librarian at the Norwegian National Centre for Ageing and Health.After removing duplicate articles from the searches for literature done using various electronic databases, all titles and abstracts from the remaining articles  and screening appears in Fig. To assess quality of the included studies the Newcastle–Ottawa assessment scale (NOS) was used. The studies were assessed according to three perspectives: (1) selection of the population/study group, (2) comparability of the groups, and (3) assessment of outcome . QualityA data extraction form was prepared that included study characteristics, including authors, year of publication, country, aim, study design/methods, number of participants, and outcomes. All researchers were involved in the process of data extraction.Any disagreements in the quality assessment and data extraction phase were discussed by the researchers until a consensus was reached.Characteristics of the included studies are presented in Table Mweighted, mean of proportions) and the range of proportions were calculated to account for the large variation in the number of participants in the studies.Due to the heterogeneity in the study designs, methods, and outcomes in the articles, we presented the findings in a narrative synthesis. Data were grouped according to symptoms, signs, comorbidity, laboratory findings, medical treatment, and mortality among NH residents confirmed to have COVID-19. For single symptoms and findings comparable across studies, a weighted mean , Sweden (n = 2), the Netherlands (n = 2), and one each from Norway, Great Britain, Spain, Italy, France, and Belgium. All studies were published in 2020 or 2021 and conducted in the first and part of second wave of the pandemic before vaccinations were initiated. Table Mweighted = 84.0%, range = 27.8%–100.0%). The number of residents in each study varied from 40 to 5256. Median age varied from 79 to 89 years, mean age from 75.2 to 88.8 years, and the age range was 51–107 years.The 19 articles in our review, hereafter referred to as “studies”, were geographically spread across nine countries that included the United States , cough , hypoxia , delirium or confusion , dyspnoea, shortness of breath or respiratory distress , and/or abdominal pain, nausea, vomiting, and/or diarrhoea .Fifteen of the studies , 37–39 iMweighted was 50.1% (3.0%–56.4%). For the studies that identified an asymptomatic course during the follow-up period, the Mweighted was 23.5% (4.0%–37.1%).Among the studies that did not identify any symptoms in COVID-19-positive NH residents at the time of testing, the Two studies, Bielza et al. and De Spiegeleer et al. , 26 reveMweighted and range were hypertension , dementia or cognitive impairment , cardiovascular disease , diabetes , renal disease , and pulmonary disease .Comorbid conditions in NH residents, as shown in Table Laboratory findings for NH residents with confirmed COVID-19 are reported in three of the articles , 23, 32 Atalla et al. found elevated C-reactive protein levels (CRP ≥ 5 mg/L) in four of 10 (40%) NH residents or whom laboratory tests were performed . By comp9/L [Atalla et al. detected a low lymphocyte count (< 0.8 k/μL) in three of 75 (4%) NH residents, whereas Poloni et al. found that 51 of 57 (89.5%) NH residents had low lymphocyte counts with a median count of 1.3 × 109/L , 32.3). In the two studies, high WBC counts  were found in seven of 87 (8%) and in 13 of 155 (8.4%) NH residents, respectively [Both Atalla et al. and Beiting et al. assessed low and high white blood cell (WBC) counts. Atalla et al. found a low WBC count (< 4 k/μL) in 13 of 81 (16%) NH residents, whereas Beiting et al. found that 61 of 155 (39.4%) NH residents displayed a low WBC count , Atalla et al. found such levels in 54 of 90 (60.0%) NH residents tested, and 47 of the 90 (52%) had low haemoglobin (Hb < 12 g/dL) . In BeitThose two research groups also reported abnormal chest X-ray results in their studies , 23. In The medical and pharmacological treatments of the NH residents confirmed to have COVID-19 are described in Table p < 0.00001) and more often male (p < 0.0001) [Transfers to hospital were reported in six of the included studies, and the rate of hospital transfers varied from 6.9% to 50% for residents with confirmed COVID-19 , 37, 39.Mortality in NH residents with confirmed COVID-19 was reported in 17 of the studies as shown in Table The aim of our systematic review was to describe the clinical expressions, characteristics, and treatments of NH residents with confirmed COVID-19. Fever, respiratory issues, and delirium or confusion were most frequently reported signs and symptoms. Not having symptoms at the time of testing or during the follow-up period was also common. Moreover, some NH residents displayed a severe course of COVID-19. The most frequently reported comorbidities among NH residents who tested positive for COVID-19 were hypertension, dementia or cognitive impairment and cardiovascular disease. Few articles reported laboratory findings or medical treatments, whether those treatments were used to improve outcomes, as part of palliative care, or as end-of-life treatment. Mortality rates due to COVID-19 were high, and dementia or cognitive impairment, changes in oxygen status, old age, and male gender may be associated with higher mortality.Regarding symptoms and signs of COVID-19, approximately half of the NH residents in the studies had fever and cough while one-third had hypoxia. Those findings align with the findings of other studies reporting these signs and symptoms in both NH residents and older adult patients in hospitals , 40, 41.Mweighted) of the NH residents was affected by the condition as a component of COVID-19, which is also described by Hashan et al. [Other atypical signs or symptoms indicating infection in NH residents could be a change in mental or cognitive state such as delirium or confusion , 43. Ourn et al. . NH resin et al. . The conIn our systematic review, changes in oxygen status were associated with higher mortality and thus represent a sign that is important to recognise among NH residents. Among patients admitted to hospital due to COVID-19, both dyspnoea and low oxygen saturation were associated with mortality . The higIdentifying the symptoms of COVID-19 in NH residents is important for early diagnosis and proper treatment before the condition worsens in addition to reducing the risk of the further transmission of SARS-CoV-2. In the case of suspected infection, having a liberal testing system to confirm or rule out COVID-19 can help to prevent the undetected spread of the virus. Due to the high percentage of asymptomatic patients, relying solely on symptom-based screening is insufficient for reliably identifying COVID-19. The presence of symptoms, such as fever and cough, should prompt further testing . Future The results of abnormal laboratory findings reported in the articles indicate elevated CRP and D-dimer levels, lymphopenia, leukopenia, and acute kidney injury among NH residents confirmed to have COVID-19. However, given the scarcity of studies that have reported such findings, it remains difficult to draw conclusions about the frequency of those findings and the significance of the test results. A meta-analysis among older adult patients with COVID-19 has shown that lymphopenia and leukopenia may be common in that population and that acute kidney injury is a common complication . AnotherIn general, frequently reported diagnoses among NH residents are hypertension, cardiovascular disease, dementia, diabetes, and chronic obstructive pulmonary disorder, and studies also show that NH residents usually display three or more underlying health conditions , 9. In oThe medical and pharmacological treatments of NH residents confirmed to have COVID-19 identified in our systematic review were used to improve outcomes, as part of palliative care, or as end-of-life treatment. The treatments described were administered early on during the pandemic, and hydroxychloroquine was used in some severe cases of COVID-19. It turned out, however, that hydroxychloroquine did not provide any benefits for patients with COVID-19. In December 2020, it was strongly advised not to use the drug . NH resiIn this review we rigorously followed both the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement and a systematic qualitative assessment system of the included studies, the Newcastle–Ottawa assessment scale (NOS). We conducted thorough literature searches using relevant databases , but the risk of missing studies cannot be ignored. The included studies were conducted exclusively in Europe or North America, possibly due to the geographical spread of the pandemic in which it first broke out and the exclusion of studies not published in English. In addition, the studies varied in sample size, length of follow-up period, and acquisition of data. Given such heterogeneity in study designs, methods, and outcomes, it proved impossible to perform a meta-analysis along with our systematic review. Our findings must therefore be interpreted with caution based on these limitations. Nevertheless, our review has allowed us to summarise important clinical findings about COVID-19 pertaining to this vulnerable population of NH residents.Our systematic review has revealed that NH residents have several risk factors for severe illness and death caused by COVID-19. In this population, COVID-19 can appear with both typical and atypical symptoms but can also be asymptomatic. Delirium can be an atypical symptom of COVID-19 among NH residents, one that warrants close attention given the severe negative consequences of the condition. Using a liberal testing system to confirm or rule out COVID-19 suspected in NHs can prevent severe courses of the disease and death due to the undetected spread of the virus. Considering that NH residents with COVID-19 preferably should be treated at their NHs, having enough high-quality staff at the facilities is vital, especially because the virus continually emerges with new variants. Future research thus needs to examine how symptoms are assessed and how COVID-19 is clinically evaluated among NH residents by NH staff. Beyond that, the treatment and care of NH residents with severe courses of COVID-19 need to be investigated in greater depth.