However, none of the egg qualities and egg components were altered by dietary MSM. The deposition of MSM in egg albumens increased in a linear manner (p < 0.05) in response to the increasing dietary MSM levels. The concentration of malondialdehyde in the egg yolk decreased at 12 weeks , as the dietary MSM levels increased. Increasing dietary MSM affected the indicators of antioxidant/oxidative stress in the serum samples, such as superoxide dismutase at 12 weeks , total antioxidant capacity at 8 and 12 weeks , and malondialdehyde at 8 weeks . Taken together, our study shows that dietary MSM has potential to be used as an antioxidant feed additive for laying hens, and can be used to produce functional eggs with health benefits for humans.This study evaluated the effects of graded levels of dietary methyl sulfonyl methane (MSM) on the laying performance, egg quality, antioxidant capacity, and the incorporation of MSM into the egg albumen of laying hens. A total of 240 73-week-old laying hens (Lohmann Brown Lite) were randomly allotted to 1 of 5 dietary treatments, with 8 replicates of 6 birds per replicate. The experimental diets were formulated by mixing corn and soybean meal-based diets with MSM to reach 0.0, 1.0, 2.0, 3.0, and 4.0 g per kg of diet, and were fed to the birds for 12 weeks. Increasing dietary MSM led to a significant quadratic effect on the feed intake and feed conversion ratio at 4 weeks ( It is a colorless solid with a sulfonyl functional group, and is the simplest form of sulfone. Due to its various biological properties, including antioxidant, antimicrobial, and anti-inflammatory, and its use for treating arthritis, MSM has been used as a functional supplement for human consumption [Methyl sulfonyl methane (MSM) is a non-toxic natural organosulfur compound with the chemical formula  in a windowless, fan-ventilated house, and the adjacent 3 cages were considered a replicate . After two weeks of an adaptation period, the layers were randomly distributed into five groups, with equal body weight and laying performance, and subjected to 1 of 5 experimental diets for 12 weeks. A corn and soybean meal-based diet was prepared  to meet The MSM content was analyzed for the control diet and it contained 0.31 g/kg of diet. MSM is a natural constituent of the environment and it is found in plants, including corn . Total SThe feed consumption per replicate was recorded monthly and used to calculate the average daily feed intake per bird. Feed was provided daily to avoid the chances of feed wastage. Egg production and egg weight were recorded daily and used to calculate the egg mass. The percentage of dirty and broken eggs was calculated as  × 100. The feed conversion ratio  was calculated on a 4-week basis for each group. On the last three consecutive days at 4, 8, and 12 weeks, six intact eggs per replicate were collected for the egg quality assessment. Eggshell color was estimated by a shell color reflectometer . Haugh unit, eggshell strength, eggshell thickness (without shell membrane) and yolk color score were assessed by a digital egg tester . Yolk color was automatically graded on a scale of 1–16, with 1 being a very pale yellow and 16 being a dark orange. The separated yolks were weighed after clearing the adherent albumen residue with filter paper. Eggshells were cleaned to remove the adherent albumen, dried at room temperature for 3 days, and weighed. Albumen weight was then calculated by subtracting yolk and dry eggshell weights from the initial whole egg weight. The separated yolks were pooled (3 yolks/replicate) and processed to determine the concentrations of corticosterone and malondialdhyde (MDA), as described elsewhere ,24,25.In a preliminary analysis, we found that egg yolks contained no MSM, but the albumen contained 0.18 g/kg (data not shown). Thus, we decided to analyze the albumen for MSM incorporation. At 12 weeks, three eggs per replicate were collected to measure the MSM content in egg albumen. The eggs were cracked open and yolk-free albumen was separated and pooled. The pooled albumen per replicate was homogenized and lyophilized . After lyophilization, the dried albumen was ground, dissolved and extracted in 50 mL methanol with an internal standard  in a 100 mL volumetric flask . Then, tMalondialdehyde is an indicator of oxidative stress ,27, and g) for 15 min and stored at −20 °C before analysis. Serum samples were used to measure various biomarkers of oxidative stress, including levels of glutathione peroxidase (GPX), superoxide dismutase (SOD), total antioxidant capacity (TAC), catalase (CAT), MDA, and 8-hydroxydeoxyguanosine (8-OHdG). The level of activity of GPX in serum samples was determined using a GSH-Px ELISA kit . SOD was analyzed using a SOD determination assay kit  and expressed as SOD activity (% inhibition rate). TAC was analyzed using a QuantiChrom antioxidant assay kit  and expressed as mmol Trolox equivalents. CAT was analyzed using an OxiSelect catalase activity assay kit . MDA was measured using an OxiSelect thiobarbituric acid reactive substances (TBARS) assay kit . 8-OHdG was determined based on oxidative DNA damage  and expressed in ng/mL.Approximately 3 mL of blood per hen (one hen per replicate) was drawn from the wing vein into a clot activator tube  at 4, 8, and 12 weeks. Serum samples were obtained by gentle centrifugation . Orthogonal polynomial contrasts were used to determine the linear and quadratic effects of graded levels of dietary MSM. The significance level was set at p = 0.011) and FCR (p = 0.049). However, the MSM-mediated effect on feed intake and FCR was not detected at 8 and 12 weeks. No significant (p > 0.05) linear and quadratic effects of dietary MSM on egg production, egg weight, and egg mass at all timepoints were noted. Dirty and cracked egg production remained between 1.11 and 2.98%, and was not affected by dietary MSM levels. Dietary MSM failed to affect the egg components and egg qualities, including the Haugh unit, eggshell thickness, or eggshell strength, at all timepoints (The production performance of the laying hens fed diets with graded levels of dietary MSM is presented in mepoints . p < 0.01) as the dietary MSM levels increased  in the egg albumen, and X represents the level of added MSM (%) in the diets).The MSM content in the egg albumen increased  with increasing dietary MSM levels, but this effect was only noted at 12 weeks.Dietary MSM supplementation did not affect the concentration of corticosterone in the egg yolks at all timepoints (p < 0.05) by increasing the dietary MSM levels. Dietary MSM did not affect the concentration of TAC in the serum samples at 4 weeks, but it had increased linearly (p < 0.05) by 8 and 12 weeks. The MDA concentrations decreased in the serum samples (p > 0.05) with increasing dietary MSM levels, and this effect was significant  at 8 weeks and marginal  at 12 weeks.The serum concentrations of the antioxidant/oxidative stress markers, including GPX, SOD, TAC, CAT, MDA, and 8-OHdG, are presented in It is clear from this study that dietary MSM can be linearly and effectively transferred into the egg albumen. However, despite supplementary MSM levels of up to 4.0 g per kg of diet, no plateau of MSM incorporation was reached for the egg albumen. In line with our finding, the systemic incorporation of dietary MSM has been reported in broiler chickens. For example, Abdul Rasheed et al.  reportedIt has been well reported that dietary MSM plays an important role in reducing oxidative stress ,15, inhiIt is known that about 99% of all egg lipids are present in the yolk, with a large percentage of unsaturated fatty acids prone to high lipid oxidation . In thisWe further monitored the antioxidant properties of serum samples from laying hens fed a diet containing dietary MSM. Dietary MSM increased SOD and TAC, but lowered MDA, in the serum samples. It is of interest that the oxidative activity of dietary MSM was noted at 8 or 12 weeks, indicating a time-dependent antioxidant effect of MSM. In line with our finding, 0.03% dietary MSM markedly increased the SOD in ducklings . SimilarIn regards to laying performance, increasing the dietary inclusion of MSM quadratically decreased feed intake and improved FCR, although this effect was only detected at 4 weeks. Our study, in part, corroborates earlier studies that showed that dietary MSM decreased feed intake in ducks  and imprAlthough none of the egg qualities were affected by dietary MSM in this study, Lim et al.  reportedIn conclusion, graded levels of dietary MSM linearly improved the antioxidant capacity in laying hens, as manifested by a decrease in MDA in the egg yolks (12 weeks), and an increase in SOD (12 weeks) and TAC (8 and 12 weeks) in the serum samples. However, it should be remembered that the MSM-mediated effects on the antioxidant and oxidative markers were exhibited in a time-dependent manner. In addition, we found that increasing MSM in the diets of laying hens linearly increased the deposition of MSM in the egg albumen. Our study shows that dietary MSM could be used as a functional additive to produce value-added MSM-enriched eggs.


We conducted a comorbidity network analysis using data from the seventh Korea National Health and Nutrition Examination Survey to systematically quantify obesity-related comorbidities.The study included 11,712 subjects aged 45 to 80 . A prevalent disease was defined as a specific disease for which a subject had been diagnosed by a doctor and was being treated. Comorbidity network analysis was performed for diseases with a prevalence of 1% or more, including overweight and obesity. We estimated the observed-to-expected ratio of all possible disease pairs with comorbidity strength and visualized the network of obesity-related comorbidities.2. The most common prevalent disease was hypertension (42.3%), followed by dyslipidemia (17.4%) and diabetes (17.0%). Overweight and obese subjects were 2.1 times  more likely to have a comorbidity  than normal-weight subjects. Metabolic diseases such as hypertension, dyslipidemia, diabetes, and osteoarthritis were directly associated with overweight and obesity. The probability of coexistence for each of those 4 diseases was 1.3 times higher than expected. In addition, hypertension and dyslipidemia frequently coexisted in overweight and obese female along with other diseases. In obese male, dyslipidemia and diabetes were the major diseases in the comorbidity network.In subjects over 45 years old, 37.3% of people had a body mass index over 25.0 kg/mOur results provide evidence justifying the management of metabolic components in obese individuals. In addition, our results will help prioritize interventions for comorbidity reduction as a public health goal. As normIt is well-known that obesity is a major risk factor for chronic diseases such as cardiovascular disease (CVD), some type of cancers, and metabolic diseases . While oFor this study, we used data from the seventh KNHANES (2016- 2018). The KNHANES is a nationally representative survey that is conducted annually to assess health-related behaviors, chronic disease conditions, and trends in food and nutrition intake. The KNHANES consists of 3 component surveys: a health interview, a health examination, and a nutrition survey. A sampling plan was conducted before every wave of the survey (every 3 years) and relied on a multi-stage sampling method. The detailed KNHANES survey method has been published elsewhere . The sev2 was considered overweight/obese. Overweight and obesity were determined based on BMI, which was calculated using data from measurements of subjects’ height and weight. Although the criterion for overweight in Asian countries is lower than that in Western countries, this study used the criterion of 25.0 kg/m2 as a general standard to define overweight. Thirty diseases were investigated using data from the seventh KNHANES survey of chronic disease conditions. They were hypertension, dyslipidemia, stroke, coronary artery disease , osteoarthritis, rheumatoid arthritis, osteoporosis arthritis, tuberculosis, asthma, diabetes, thyroid disease, stomach cancer, liver cancer, colorectal cancer, breast cancer, cervical cancer, lung cancer, thyroid cancer, depression, atopic dermatitis, allergic rhinitis, sinusitis, otitis media, cataract, glaucoma, macular degeneration, kidney failure, hepatitis B, hepatitis C, and cirrhosis. A prevalent disease was defined as a specific disease in a subject that had been diagnosed by a doctor and was being treated at the time of the survey. Hypertension and diabetes specifically were determined using blood pressure and fasting blood glucose data according to the criteria reported by the Korea Centers for Disease Control and Prevention [A person with a BMI equal to or more than 25.0 kg/mevention ,13. Thes2) as a node. For comorbidity strength, we estimated the observed-to-expected ratio (OER) of all possible disease pairs based on previous studies of comorbidity networks [The research goal of the comorbidity network was to assess whether diseases tend to appear together more frequently than expected. The basic elements of network analysis consist of nodes and edges. Nodes indicate specific diseases, and edges indicate the coexistence of a pair of diseases. Due to the nature of the study design, the edges between diseases have no directionality. To identify obesity-related comorbidities, we considered overweight and obesity .For summary statistics, the results for continuous variables were presented as weighted means with standard error (SE), while those for categorical variables were presented as the number of subjects with weighted percentages based on multi-stage sampling. The 30 diseases were listed according to the prevalence rate, and diseases with a prevalence rate of 1% or more were tabulated. The risk of having a prevalent disease according to sex or obesity was evaluated using logistic regression and results were expressed as an odds ratio (OR) with a 95% confidence interval (CI). Statistical significance was assessed at p-value < 0.05 with a 2-tailed test. All statistical analyses were performed using SAS version 9.4  or R version 3.6.2  Committee of the Ewha Womans University Hospital (IRB No. EUMC 2020-08-007).2. Of that percentage, female accounted for 49.16% . It was reported that 70.43%  of obese subjects had at least 1 of the 30 prevalent diseases, and 40.16% (SE 0.86) had 2 or more prevalent diseases. In non-obese subjects, 56.38%  of subjects had 1 prevalent disease, and 26.63%  had 2 or more prevalent diseases  had a BMI that exceeded 25 kg/mdiseases .2) and having a disease with a prevalence rate of more than 1% are presented in The associations between high BMI (≥ 25.0 kg/m2 or higher (data not shown).The results of the comorbidity network analysis related to obesity are shown in We also evaluated the rates of prevalent diseases in obese subjects by sex . DyslipiWe evaluated the major comorbidities of obese subjects by sex using network analysis. In females, 3 clusters were identified: (1) metabolic diseases, thyroid disease, depression, and ophthalmic diseases were classified into one cluster; (2) musculoskeletal diseases; (3) otorhinolaryngologic and coronary artery diseases. Diseases such as thyroid disease and depression were shown to accompany dyslipidemia, and the proportion of diabetes and cataract comorbidities was 1.64 times as high as expected  . In obesThrough comorbidity network analysis, we identified the major obesity-related comorbid diseases using large-scale survey data. Metabolic diseases such as hypertension, dyslipidemia, diabetes, and osteoarthritis were directly associated with overweight and obesity, and the comorbidity risk in overweight and obesity subjects was 2.1 times higher than in normal-weight subjects. Furthermore, in overweight and obese people, dyslipidemia, hypertension, and diabetes were frequently accompanied by other diseases, and were characterized as close to other diseases. Moreover, based on their betweenness, we found that these metabolic diseases play a central role in mediating between diseases in the network. Therefore, managing metabolic components and weight loss reduces the likelihood of developing BMI-related diseases and comorbidities.Although obesity has been accepted as a predisposing factor for the development of various chronic diseases such as CVD and metabolic diseases, the definition of obesity-related diseases has unclear boundaries. Comorbidity network analysis provides insights to help understand obesity-related diseases and can provide information for patient care and treatment in a medical setting ,10,16. BThe relationship between metabolic diseases and high BMI is well established based on accumulated evidence ,7. LargeThe prevalence of musculoskeletal diseases was higher in obese females than in obese males, and the coexistence of osteoarthritis and hypertension was also found to be significant in obese females, which aligns with the results of previous studies -24. The Among endocrine diseases, thyroid disease was significantly associated with overweight and obesity. Although the types of thyroid diseases associated with overweight and obesity have not been investigated in detail, a study in Korea showed that hypothyroidism has a higher prevalence than hyperthyroidism . Of thesThere were several points to keep in mind when interpreting the results. Our results were derived from a cross-sectional survey, so an analysis of causality is not appropriate. Some uncertainty by measurement error and self-reported disease information may have influenced the results. The data source used did not include patients with severe conditions who had been hospitalized, which would have affected prevalence estimates. Our study utilized measured BMI information, but the diseases that could be considered were limited according to the scope of the survey data. Although a positive association between obesity and non-alcoholic fatty liver disease (NAFLD) has been reported , NAFLD iNevertheless, results were obtained using data representing the Korean population, so there are benefits to the generalized scope of the results. By using survey data rather than administrative data, our study provides information on obesity-related comorbidities through a systematic approach. Its findings can motivate the public to manage and prevent, as well as better understand, overweight and obesity. Finally, through network analysis, we systematically evaluated obesity-related diseases and provided insights for further research. The study can also provide helpful information for prioritizing interventions for comorbidity reduction as a public health measure.In summary, taking into account the possibility of modification, preventing overweight and obesity through weight loss is expected to reduce the risk and severity of various chronic diseases. Furthermore, managing metabolic components in obese persons reduces the chance of developing comorbid diseases.


Testing is a key measure to control the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we empirically compared two SARS-CoV-2 testing strategies.We used data from a Swiss single-centre, outpatient cohort study . A “restricted” strategy was applied to individuals with respiratory symptoms and/or fever and selected risk factors, or an epidemiological link and an “extended” strategy included any clinical symptoms without restriction, irrespective of risk factors and exposure. Data on infection, symptoms, viral load were collected during the first wave  and patients were followed up for clinical complications and hospitalisations until August 31, 2020.vs. 25.0%, 12.3% vs. 20.8%, and 0.7% vs. 2.3%). In the whole cohort, participants included in the extended strategy had a lower number of symptoms  and visits occurred earlier after symptom onset . Among positive cases, the viral load was higher for the extended strategy (p < .001).Infection, clinical complications, and hospitalisation rates were lower for those in the extended strategy compared with the restricted strategy (17.2% These findings highlighted the crucial importance to implement a widespread testing strategy to achieve a better understanding of the infection, to mount an effective control response, by capturing people when their viral load is highest. A widespread test strategy should be available without barriers to help break the chains of transmission. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), identified in January, 2020, caused a worldwide outbreak and was declared a pandemic by WHO on March 11, 2020 , to prepAt the beginning of the first wave of the epidemic, no widespread testing strategy was used. As clinicians and researchers were unaware of the wide clinical spectrum of symptoms related to COVID-19, testing strategies were generally oriented toward more serious conditions , 12. LatThe aim of our study was to compare two testing strategies used in Switzerland, a country with one of the highest numbers of SARS-CoV-2 infection per capita worldwide : a “restWe did a single-centre cohort study of outpatients presenting for SARS-CoV-2 testing at the primary case medicine department of Geneva University Hospitals (HUG), Geneva, Switzerland. Data were collected during the first wave of the epidemic, between March 11, 2020 and April 21, 2020. Information on clinical complications and hospitalisation were collected until August 31, 2020.HUG is one of the largest university hospitals in Switzerland and in Europe with 2,008 beds and 11,945 healthcare workers. It serves a population of 500,000 residents. In 2019, 64,000 hospitalisations, one million outpatient visits, and 125,000 emergency visits were recorded. HUG was the sole hospital in the canton of Geneva admitting COVID-19 patients. On March 2, 2020, four outpatient SARS-CoV-2 dedicated testing centres were opened by the HUG and patients were oriented to these centres, or to the emergency department for the more severe cases. Individuals tested in private clinics, at the emergency department, and in nursing homes were not included in the study. A standardised questionnaire was completed by a nurse, a trained medical student, or a doctor. As knowledge on the infection evolved over time, the questionnaire was changed accordingly. Differences are explained in the Measures subsection. All patients completed the same questionnaire. The nurse/trained medical student/doctor was not blinded to the patient’s group (restricted and extended strategies), because they need to decide whether the patient should be tested or not.The Cantonal Ethics Research Committee of Geneva approved the study protocol (no. 2020–00813). Following the article 34 of the Swiss Human Research Act, we were allowed to use health-related personal data collected in routine medical files in the absence of informed consent. Patients who refused the use of their medical data for research purposes were excluded .The recruitment was solely based on patients attending to testing centres during the study period. Patients with severe symptoms were oriented to the emergency department rather than the outpatient testing centres. Exclusion criteria were: 1) being less than 16 years old, 2) refusal of the use of their medical data for research purposes, and 3) exceptions to the testing strategies described below. We also excluded hospitalised infected cases who were non-resident in the canton of Geneva from the analyses on clinical complications, as they could have been followed-up or hospitalised elsewhere.Participants included the general population (restricted strategy) vs. individuals working at HUG  and healthcare workers in the canton of Geneva .The testing strategy for the general population was conducted in line with the recommendations of the Swiss national health authorities . IndividA more liberal strategy was used for all individuals working at HUG and healthcare workers. They were offered to be tested for any clinical symptoms without restriction. All individuals working at HUG or healthcare workers of the canton of Geneva were classified in the extended strategy, even those meeting the criteria for the restricted strategy .In both strategies, during a short period , access to testing was reduced to individuals with cough, fever, and risk factors due to kit/reagent shortage.SARS-CoV-2 infection was detected by RT-PCR performed on naso- or oropharyngeal swabs and processed in the HUG virology laboratory, the Swiss national reference laboratory for SARS-CoV-2. Swabs were placed in a collection tube with 150 μL of virus preservation solution. Viral RNA was measured by the cycle threshold (Ct) values targeting the E gene on different diagnostic platforms . Results of the RT-PCR were given back as positive or undetected. Ct values were available for n = 500 positive cases, those tested with Roche COBAS 6800. Ct values were not systematically registered with other diagnostic platforms, especially at the beginning of the pandemic. Ct values are inversely proportional to viral load. Patients with undetected RT-PCR, but strong clinical evidence for SARS-CoV-2 infection, were classified as “probable” cases and counted as positive cases for this study. Finally, some participants were not tested as they did not meet the recommendations for the testing strategy .The triage questionnaire included several symptoms compatible with COVID-19 (not necessarily used to decide whether the patient should undergo a test): anosmia, runny nose, sore throat, cough, difficulty breathing, fever, muscle pain, chills, headache, abdominal symptoms, fatigue, and thoracic pain. Anosmia and headache were added on March 24, 2020. Difficulty breathing, abdominal symptoms, fatigue, and thoracic pain were added on April 1, 2020. These symptoms were reported as free text in the section “other symptoms” in previous versions of the questionnaire and then recoded. We also collected the date of onset of symptoms, which enabled us to identify the time between first symptoms and visit to the testing centres .Risk factors for severe illness or complications were defined accordingly to Swiss and international recommendations and included: age 65 years or older; hypertension; chronic respiratory disease , diabetes, heart diseases , and immunosuppression . Participants were asked whether they had a contact with a confirmed SARS-CoV-2 case or travelled abroad in the previous 14 days. Age, gender, and country/canton of residence were also assessed.COVID-19-related hospitalisation at HUG was collected from patients’ medical records. Patients were hospitalised if they had a high severity score for pneumonia (CURB-65 score ≥ 2), a need or increased need of oxygen, sustained tachypnoea, a poorly-compensated comorbidity, deteriorated general condition, or worsening disease. Criteria for hospitalisation remained the same during the entire study period. According to the local guidelines, mild and moderate pneumonia, not filling the aforementioned criteria, were treated and followed as outpatients and not hospitalised.COVID-19-related clinical complications were assessed using hospitalisations (see above) and any COVID-19-related visit to the hospital. These visits included worsening, recurrence or persistence of COVID-19-related symptoms, as well as visits planned to monitor severe COVID-19 symptoms .2, and negative binomial regressions with pseudo R2. We then investigated whether there were differences between the two strategies in the proportion of infected cases, using Chi-square tests with Cramer’s V. We reported likelihood Chi-square contributions and 95% confidence intervals (CI) for the prevalence rates. The relationship between strategies and symptoms was tested using logistic  and negative binomial (number of symptoms) regressions. We also performed the same analyses on the subsample of participants who tested positive. Finally, we tested the relationship between strategies and Ct values using linear regression.Data were analysed at the visit level. We first computed descriptive statistics for all variables. We also performed preliminary analyses comparing demographics, risk factors, number of visits, and exposure between groups, using Chi-square tests with Cramer’s V, linear regressions with RWe provided a description of the hospitalisation and clinical complications rates with 95% CI for each strategy and tested the difference using a Chi-square test with Cramer’s V. The same analyses were performed on the subsample of participants who tested positive or who were probable cases.We ran several sensitivity analyses. First, we analysed data at the level of the visit as some patients had repeated visits. We ran all the analyses described above  taking into account the clustering using mixed-effects regression models. As the results were similar, analyses at the level of the visit are presented. Second, as the standardised questionnaire was not the same during the whole study period, we ran sensitivity analyses on the period for which all symptoms were listed in the questionnaire . Results were also similar. In the analyses of clinical complications, we also performed sensitivity analyses 1) using the continuous age instead of including age ≥ 65 years in the number of risk factors and 2) excluding asymptomatic patients. Results were again similar. Then, we conducted analyses without probable cases to ensure that the results were the same. Finally, we replicated all analyses on a second subset of participants to control whether there was an effect of being a health care worker. We restricted the extended strategy to the subsample of participants not in contact with patients . Results were similar as those reported in the Results section, except for Ct values for which we could expect a lack of power (n = 18 in the extended strategy). All analyses were done with Stata version 15.We registered 7,401 visits to the dedicated testing centres. Forty-two participants , were excluded because they did not consent to the use of their data for research purposes. Of the 7,354 remaining visits, 1,023 (13.9%) were excluded because they were exceptions to the testing strategies (n = 792 for the restricted strategy and n = 213 for the extended strategy). A total of 6,331 visits were included in our analysis , with a mean age of 41.2 ± 12.9 years and 62.6% of females. These corresponded to 2,956 participants for the restricted strategy and 2,998 for the extended strategy. Participants in the extended strategy were more likely to come several times: 9.4% came at least two times versus 2.2% of those in the restricted strategy , with the extended strategy resulting in a lower number of visits with a positive RT-PCR (likelihood χ2 ratio contribution: -224.0), a higher number of visits with a negative RT-PCR (likelihood χ2 ratio contribution: 392.3), and no RT-PCR (likelihood χ2 ratio contribution: -106.5).For the restricted strategy, 25.0%  of visits were infected, including 3 probable cases. A total of 8.2% (n = 249) of visits did not lead to a RT-PCR. For the extended strategy, 17.2%  of visits were infected (including 5 probable cases). A total of 4.1% (n = 136) of visits did not lead to a RT-PCR. There was a significant difference between strategies vs. 4.57 symptoms on average; p < .001). Participants from the extended strategy were more likely to come in the three first days after symptoms onset . Among positive cases for which Ct values were available (n = 500), Ct values were significantly lower in the extended strategy in comparison with the restricted strategy .The overall hospitalisation rate of patients resident in Geneva  was 2.3%  for the restricted strategy and 0.7%  for the extended strategy. Among positive or probable cases  of Geneva residents, 9.1% (95% CI: 7.2–11.6) of the participants were hospitalized for the restricted strategy and 4.1% (95% CI: 2.4–6.8) for the extended strategy; 20.8%  had clinical complications for the restricted strategy and 12.3%  for the extended strategy.vs. 25.0%) and hospitalisation rate  were lower for the extended strategy compared with the restricted strategy. More restricted testing strategies are skewed towards more severe cases requiring hospitalisation and, therefore, do not provide a good overview of the detrimental consequences of the disease at the population level [This study compared two testing strategies to provide empirical support to the potential benefits of widespread SARS-CoV-2 testing. Our findings showed that the infection rate  less carefully because they can access testing easily. To date, these aspects have not been investigated in empirical public health research.Given the benefits of the widespread strategy from a public health and infection control perspective, barriers to testing should be avoided. In Switzerland, the cost of visit and testing was 310.30 Swiss francs (US$ 334/287 euros) at the beginning of the epidemic and has now become free of charge end of June 2020. Even if Switzerland has universal health care coverage, the cost was not necessarily covered by health insurances because of deductibles and out-of-pocket payments , 22. In This study has some limitations. First, information collected in the standardised questionnaire was based on self-reports. Even if questionnaires were always checked by a health care professional, they may have lacked precision. Second, we used different versions of the standardised questionnaire. New symptoms were added when they appeared as frequent SARS-CoV-2 symptoms. Despite the recoding of symptoms listed in the “other symptoms” section, these symptoms might have been underreported in earlier versions of the questionnaire. However, our sensitivity analyses yielded similar results and the standardised questionnaire was the same for the two testing strategies. Finally, the populations for the restricted and extended strategies were not the same. Individuals working at HUG and healthcare workers were more likely to have a good health literacy  and testing was more easily available for them (“proximity bias”). This may have inflated the differences between the two testing strategies and studies comparing strategies in the same population are required to achieve a better understanding of their benefits and limits.Our results highlight that widespread testing is crucial to understand and control the spread of infection, and to maximize identification of infected people. Access to free testing is essential, not only to achieve infection control, but also to eliminate any discrimination between the different layers of society.S1 File(XLSX)Click here for additional data file.


The stress response of plants to spaceflight has been confirmed in contemporary plants, and plants retained the memory of spaceflight through methylation reaction. However, how the progeny plants adapt to this cross-generational stress memory was rarely reported. Here, we used the ShiJian-10 retractable satellite carrying Dongnong416 rice seeds for a 12.5-day on-orbit flight and planted the F2 generation after returning to the ground. We evaluated the agronomic traits of the F2 generation plants and found that the F2 generation plants had no significant differences in plant height and number of tillers. Next, the redox state in F2 plants was evaluated, and it was found that the spaceflight broke the redox state of the F2 generation rice. In order to further illustrate the stress response caused by this redox state imbalance, we conducted proteomics and metabolomics analysis. Proteomics results showed that the redox process in F2 rice interacts with signal transduction, stress response, and other pathways, causing genome instability in the plant, leading to transcription, post-transcriptional modification, protein synthesis, protein modification, and degradation processes were suppressed. The metabolomics results showed that the metabolism of the F2 generation plants was reshaped. These metabolic pathways mainly included amino acid metabolism, sugar metabolism, cofactor and vitamin metabolism, purine metabolism, phenylpropane biosynthesis, and flavonoid metabolism. These metabolic pathways constituted a new metabolic network. This study confirmed that spaceflight affected the metabolic changes in offspring rice, which would help better understand the adaptation mechanism of plants to the space environment. In order to further explore deep space and take advantage of the resources of other parts of the solar system, many countries have proposed space missions such as manned landing on the moon, landing on Mars or even the construction of planetary bases . Unlike 2+ signal transduction, etc. [Current research has confirmed that spaceflight would produce a stress response to plants. After a long period of spaceflight, rice seeds showed no germination or were undeveloped or elongated after germination without cell division . The somon, etc. . The preon, etc. . TherefoTo clarify, the intergenerational inheritance of spaceflight in rice will help to better reveal the intrinsic mechanism of spaceflight mutagenesis. Here, we reported how the offspring rice responded to spaceflight, and even if there was no direct processing of spaceflight in the F2 generation, some changes were still inherited. This research provides a new perspective for a better understanding of the genetic effects of spaceflight.First, we evaluated the changes in some traits of offspring rice. Compared with the control group, the germination rate of the F2 generation spaceflight group (SP2) did not change significantly A. There In order to preliminarily evaluate whether the spaceflight caused the stress response of offspring rice, we determined the physiological indicators used to characterize the stress response. In this study, H2O2, MDA, electrolyte leakage rate (EL), and soluble sugar (SSC) contents increased significantly in the SP2 group of TLS and TS D–G. In aTo study the response program of offspring rice to the spaceflight, we used iTRAQ proteomics marker technology to quantitatively study the protein changes in offspring rice at different growth and development stages. In this study, a total of 3674 proteins were identified. We exceeded 1.2-fold-change and low 1/1.2-fold-change as the up- and downregulated standards. In the TLS and the TS, there were 363 and 337 differentially abundant proteins (DAPs) , respectp < 0.05 were considered to be a biological process (BP) that significantly changes. In total, 36 BPs were significantly enriched in TLS , glutathione transferase, sodium/calcium exchanger NCL1, calcium homeostasis regulator chor1, GRAM domain, Class III peroxidase 65, which showed the same expression abundance trend in the TLS and TS, were selected for transcriptional analysis. In TLS, the gene expression patterns of  profile , which suring TS , which iProteomic studies have proved that spaceflight caused the offspring of rice to respond. However, the realization of protein function should ultimately be reflected at the metabolic level. Therefore, we used Liquid Chromatography Mass Spectrometry (LC-MS) to conduct non-targeted metabolomics studies on offspring rice. In order to evaluate the impact of stress memory on rice at the metabolic level, we used principal components to analyze the distribution of metabolites in the control and treatment groups at different periods . The conHierarchical clustering was used to further analyze the effect of space flight stress memory on metabolites in different growth stages of offspring rice . The resp values ≤ 0.01 are significantly related. Next, we used Cytoscape 3.9.0 to visualize the network . A total of 123 metabolites changed significantly during the TLS . The results showed analytically similar results to PCA . We defi the TLS , and the the TLS A. In add the TLS , among w the TLS B. In ord the TLS C,D. In t the TLS C, of whi the TLS D. We als the TLS C.Hierarchical clustering was used to further analyze the effect of spaceflight on metabolites in different growth stages of offspring rice . The resp values ≤ 0.01 are significantly related. Next, we used Cytoscape 3.9.0 to visualize the network  was used to integrate biochemical pathways and chemical relationships and connect different metabolic pathways through key metabolites in series to reveal the inherent biological effects. In order to obtain key information about the offspring rice responses to spaceflight at the metabolic level, we used MetaMapp to analyze the interaction of different metabolites. The PubChem database was used to obtain the structural information of the metabolites, the KEGG database was used to obtain the KEGG codes of the metabolites, the interaction analysis was performed in the MetaMapp online database, and the interaction network was visualized using Cytoscape 3.9.0  in plants ,19,20,21S stages . At the S stages . These re damage . Furthere damage ,26. Glut2+ signal, and hormone signal crosstalk [Studies have confirmed that oxidative stress signals can activate downstream signal cascades . Our resrosstalk .2+ signal has been confirmed to be involved in abiotic stresses such as drought, cold, and dehydration [Caydration ,30. In tydration , which sSmall GTP-binding protein RAB and calcium binding protein further interacted with plant hormones IAA, ABA, GA, BR, and regulated stress signals ,31,32. TDNA double-strand break (DSB) produced by ionizing radiation during spaceflight was considered to be the main factor posing a serious threat to genome stability , and genTranscription factor (TF) played an important role in plant stress response by interacting with cis-acting elements in the promoter and then regulating the expression of its target genes . Our preFor most eukaryotic genes, introns must be spliced from the precursor mRNA (pre-mRNA) for various processing to produce mature mRNA for protein translation ,45 ThereNotably, the expression of ribosomal 30S subunit and ribosomal 50S subunit was upregulated in this study , while tThe above results indicated that the oxidative stress generated by spaceflight has caused the instability of the offspring rice genome, leading to changes in the process of gene transcription and post-transcriptional modification. At the same time, the protein synthesis rate in the progeny rice was reduced, and the subsequent protein processing and degradation processes were affected. These changes may cause the metabolic rearrangement of offspring rice to adapt to the impact of spaceflight.Spaceflight induced changes in rice protein levels in offspring, which aroused our attention towards metabolic networks. We used MetaMapp to construct the metabolic network of spatial progeny rice, hoping to reveal how the progeny rice can adapt to spaceflight by reshaping the metabolic network . Amino aAccording to reports, as the basic elements of protein, amino acids can be used as effective antioxidants and accumulate in plants under various abiotic stresses . Here, wSugar has been characterized as an important compound that plants responded to abiotic stress . SolubleUnder most abiotic stress conditions, leaf starch content decreases in response to abiotic stress, and starch degradation in response to stress was usually related to an increase in tolerance . Starch Our previous work has observed the effects of spaceflight on the metabolism of cofactors and vitamins in the parent rice . NicotinTo further understand the genetic mechanism of progeny rice for space flight, here we conducted a comprehensive analysis of previous reports and current results . In TLS,The experiment was part of the SJ-10 space project, which was launched from the Jiuquan Satellite Launch Center in April 2016. The spaceflight parameters were consistent with what we reported earlier ,13. Acco2O2 and MDA, respectively. In short, about 200 mg of rice leaves were homogenized (0.1% w/v) in 2 mL of trichloroacetic acid and centrifuged at 4 °C to obtain the supernatant for use. Then, 0.75 mL pH = 0.7 potassium phosphate buffer and 1 mL potassium iodide (1 M) were added to 0.25 mL supernatant and mixed, the absorbance was read at 390 nm, and the H2O2 content was calculated. For MDA, we added 1.5 mL of thiobarbituric acid to 0.5 mL of supernatant, and after reacting at 90 °C for 20 min, the reaction was terminated on ice. Finally, the absorbance at 535 and 600 nm was read to calculate the MDA content.We used the methods described by Yu et al.  and HeatFor the determination of antioxidant enzyme activity, we placed about 0.5 g of rice leaves in 5 mL phosphate buffer  and homogenized on ice. After fully grinding, the supernatant was collected by centrifugation to obtain the crude enzyme extract for activity analysis. The activity of SOD and APX was measured according to the method described by . The catWe used the method described by LUTTS et al.  to deterFor soluble sugars, we used the method described by BAILEY et al.  for detem/z, and the resolution of the primary mass spectrum was 70,000 at m/z 200. The mass-to-charge ratios of peptides and peptide fragments were collected according to the following method: 10 fragment maps (MS2 scan) were collected after each full scan. MS2 Activation Type was HCD, isolation window was 2 m/z, MS resolution was 17,500 at m/z 200, and normalized collision energy was 30 eV. The original data of mass spectrum analysis was RAW file. The RAW file was submitted to the Mascot server through Proteome Discoverer1.4, the established database was selected, and then the database was searched. The Proteome Discoverer1.4 software was used to quantitatively analyze the peptide reported ion peak intensity. The predicted protein was downloaded from the Uniprot database . In order to determine the relative difference in protein abundance, we defined proteins with a fold change rate ≥ 1.2 or ≤0.83 and p < 0.05 as differentially abundant proteins (DAPs).The leaves of 5 rice plants were randomly selected to form a single biological replicate. For the proteomic experiment, we conducted 3 biological replicates. Protein extraction, LC-MS analysis, protein identification, and relative quantification were carried out according to the methods we previously reported ,12. Simpv/v) was added for subsequent HPLC-MS/MS analysis. The parameters of HPLC and MS have been reported in detail in our previous studies [http://www.metaboanalyst.ca/, accessed on 4 November 2021). Principal component analysis (PCA) was undertaken using R software.Similar to proteomics, we randomly selected 5 rice leaves to form a single biological replicate and created 6 biological replicates. The metabolites were extracted and identified according to our previously reported methods . In shor studies . ProteoWw/v) denaturing agarose gel electrophoresis and Micro Drop  were used to evaluate the quality and concentration of total RNA. Next, the TaKaRa kit  was used to reverse transcribe total RNA into cDNA. SYBR Premix Ex Taq II  was used to detect gene expression. The relative expression level of each gene was calculated as (2−ΔΔCT) [The same method as we reported earlier was followed ,12. The (2−ΔΔCT) . All prihttp://www.kegg.jp/, accessed on 7 December 2021) was used to analyze the major metabolic pathways of DAPs and DEMs. We believed that the GO terms and KEGG pathways were significantly enriched when p values ≤ 0.05.Gene Ontology and MAPMAN were used for protein function annotation. Kyoto Encyclopedia of Genes and Genomes (KEGG) (This study investigated the changes in protein and metabolic levels of offspring rice at different growth and development stages caused by spaceflight. Our findings suggest that spaceflight elicits a stress response in offspring rice, and that this stress signal results from a disruption of redox balance in the plant. ROS signaling triggers the crosstalk between calcium ion signaling and hormone signaling, affecting gene transcription and post-transcriptional modification processes, which in turn affects protein synthesis and modification processes. In addition, changes in the magnetic field during spaceflight led to the study of 40S ribosomes and 60S ribosomal subunit abundance was reduced, which was the most important factor leading to the differential abundance of proteins in progeny rice. Furthermore, we demonstrated at the metabolic level that spaceflight remodeled the metabolic network of offspring rice, especially amino acid metabolism, sugar metabolism, vitamin and cofactor metabolism. This study revealed the response mechanism of offspring rice to spaceflight from the perspective of metabolomics and proteomics, and provided basic data for further exploration of the biological effects of spaceflight.


The purpose of this article is to consider chromosome structure and evolution, chromosome numbers and sex chromosome systems, which all together constitute the chromosomal basis of reproduction and are essential for reproductive success. We are based on our own observations and literature data available for all major lineages of Paraneoptera including Zoraptera (angel insects), Copeognatha , Parasita , Thysanoptera (thrips), Homoptera , Heteroptera (true bugs), and Coleorrhyncha (moss bugs). Terminology, nomenclature, classification, and the study methods are given in the first paper of the issue (This article is part (the 4he issue . The structure of chromosomes and mechanisms of their evolution, the number of chromosomes and the chromosomal sex determination constitute the foundation of reproduction and are crucially important for reproductive success.Paraneoptera insects are characterized by holokinetic chromosomes. The only intriguing exception to this rule is the order Thysanoptera (thrips) in which all so far studied representatives of both suborders, Terebrantia and Tubulifera, were shown to have monocentric chromosomes  ; Dermaptera (Polyneoptera); Copeognatha [=Psocoptera], Parasita [=Phthiraptera], Homoptera, and Heteroptera (Paraneoptera); Lepidoptera and Trichoptera (Oligoneoptera) (Coleorrhyncha and enigmatic Zoraptera (both from Paraneoptera) also have holokinetic chromosomes  . Since tmoptera) . The ancmoptera) . Holokinmoptera) . Among ieoptera) . More revolution .The transition from monocentric to holokinetic state occurred, apparently, by accident; however, holokinetic state itself is speculated  to repreCenH3), which is an essential chromatin component of centromeres in most eukaryotes  where both sexes develop as diploids, but maleness is determined by inactivation or loss of paternal chromosomes, making males functionally haploid . Finally, true parthenogenesis exists in some paraneopteran insects occurring either in separate species or on higher taxa level, when female embryos develop from unfertilized diploid eggs  system. Some species have complex systems with multiple X or (much rarer) multiple Y-chromosomes, which evolve mainly by fissions of the ancestral sex chromosomes. Others possess so-called neo-XY systems that have derived from the X(0) system by the fusion of the X chromosome with an autosome, resulting in a neo-X chromosome, and the homologue is transformed into a neo-Y chromosome . A numbeeggs see .One of the basic features of holokinetic chromosomes is that their fragments retain centromere activity and the ability to segregate to the poles, which has been demonstrated in experiments with X-ray irradiation .Ephestiakuehniella Zeller, 1879  that radiation-induced chromosome fragments are regularly inherited by both somatic and germ cells and can be transmitted through more than 50 generations suggesting that they persist as long as their active kinetochore elements are preserved  (Cyperaceae) demonstrates an exceptional chromosome number series with nearly continuous range from 2n=12 to 2n=124 and substantial variation of the 2n within many species  (Pieridae), the 2n gradually decreases from 106 in Spain to 56 in eastern Kazakhstan  exhibits unusual interspecific diversity in chromosome number varying from n=10 to n=134 (Polyommatus (Plebicula) atlanticus , displays 2n=ca. 448–452, the highest chromosome number among all the non-polyploid eukaryotic organisms  includes 2n=29(26+X1X2Y) in males  exhibits an extraordinary 48-fold variation in chromosome number (2n=4–192) and extensive chromosomal variation within numerous morphologically defined species  chromosome numbers, the authors explored two models for the evolution of chromosome number, one of which included both fusion/fission and polyploidy, and the other only fusion/fission events. It is of interest that the analysis covering a total of 4,393 species and 599 genera, and using various approaches detected no significant difference between taxa with different chromosome types suggesting that characteristics other than “holocentricity” and “monocentricity”  can be key to determine rates of chromosome number changes , Parasita (=Phthiraptera), Thysanoptera, Homoptera, Heteroptera, and Coleorrhyncha.To test whether insects with monocentric and holokinetic chromosomes differ in the amount and rate of chromosomal rearrangements,  changes . AlthougParaneoptera, including Zoraptera (angel insects), Copeognatha , Parazita , Thysanoptera (thrips), Homoptera , Heteroptera (true bugs), and Coleorrhyncha (moss bugs). In most cases, chromosome analysis was performed using both conventional cytogenetic techniques  and FISH mainly with rDNA and telomeric (TTAGG)n probes. Methods, terminology, nomenclature, and classification are given in the first paper of this issue , for suborders within the order.Here, we review and discuss basic data on chromosome numbers and sex chromosome systems separately for each Zoraptera (known as angel insects) are minute, less than 3 mm long, insects of cryptic habits living under bark, in humus, termite nests, etc. This is one of the lesser-known insect lineages in the world in terms of distribution, diversity, mode of life, reproductive biology, genetics, etc. The order currently contains a single genus Zorotypus Silvestri, 1913 constituting the family Zorotypidae, with 44 extant and 13 fossil species  are mostly small insects inhabiting terrestrial ecosystems; representatives of certain families are closely related to human dwellings and even considered as pests in storage facilities. Psocoptera are a basal taxon of Paraneoptera  and retain most archaic features. Troctomorpha comprise 536 species  and include highly specialized forms. The largest suborder Psocomorpha, considered as the most evolutionarily advanced group of Copeognatha, comprises 5,028 species  (Copeognatha (=neoptera  comprisiamilies) .Psocomorpha  to Troctomorpha. Diploid chromosome numbers range from 13/14  found in two species of Psocomorpha to 29/30 reported for two species of Trogiomorpha; a sex chromosome system X(0) is characteristic of all bark lice species, with the exception of two species of the family Amphipsocidae (Psocomorpha). Amphipsocusjaponicus Enderlein, 1906 and Kolbiaquisquiliarum Bertkau, 1882 have a neo-XY system, which evolved due to chromosomal rearrangements involving autosomes and sex chromosomes in an ancestral karyotype with an X(0) system (Psocoptera demonstrate a clear mode at 2n=16A+XX/X(0). This chromosome complement is found in nearly 90% of the studied species  and in each of the 3 suborders. It is assumed that the modal karyotype (type or basic) is the ancestral one in the evolution of Copeognatha  (Caeciliusidae), Ectopsocusmeridionalis Ribaga, 1904 (Ectopsocidae), and Peripsocussubfasciatus  (Peripsocidae), have 2n=3x=27(24A+XXX). Their karyotype arose from the putative ancestral one, 2n=18(16A+XX), by adding one more haploid set, n=9(8A+X)  from 51 genera and 21 families have been studied cytogenetically. Of these, 80 species  belong to ) system , 2009. Peognatha . This as=9(8A+X) , 2006. TPsocomorpha, Psococerastisgibbosa , Blasteconspurcata , and Amphipsocusjaponicus, were studied using C-banding, silver impregnation and sequence-specific fluorochromes CMA3 and DAPI (NORs) are located differently in these species: on an autosomal bivalent, on the X-chromosome, and on the neo-XY bivalent, respectively. It was also shown that these species have a small amount of C-heterochromatin, which localizes as a tiny blocks in terminal regions of chromosomes and consists of AT-rich DNA, except for the NOR regions, which are both AT- and GC-rich, just like the X-chromosomes. Some minor differences in the above characters were observed between species and between different chromosomes of a particular species. It was repeatedly shown, that fluorescence in situ hybridization (FISH) helps identifying individual chromosomes and tracing, thus, their behavior in meiosis of “holokinetic” insects n considered ancestral for the class Insecta in general , the closest relatives of Copeognatha, include obligate ectoparasites of birds and mammals. The order is divided into Mallophaga (Amblycera + Ischnocera) and Rhynchophthirina known as chewing or biting lice, respectively, and Siphunculata (=Anoplura) known as sucking lice  to Ischnocera; and only 3 species  to Rhynchophthirina  belong to Amblycera, 4 species  to Ischnocera, and 7 species  to Siphunculata , and the highest count is found in Ischnocera  as Gonioidesstylifer Nitzsch, 1818).ing lice . There ahthirina . Chromosunculata . SurprisPediculushumanuscapitis De Geer, 1778 and Pediculushumanushumanus Linnaeus, 1758  , an unusual genetic system when males transmit only their maternally derived chromosomes.C-banding experiments failed to reveal constitutive heterochromatin in karyotypes of human head- and-body lice, nculata) . The gen repeats . Using aThysanoptera  encompass minute insects, which are usually only a few mm in length. Most thrips feed on fungi, flowers and leaves of green plants, less often on mosses and detritus. Thrips are distributed worldwide being more abundant in tropical, subtropical, and temperate regions. Thysanoptera are a monophyletic group subdividing into the two suborders, Terebrantia with about 2,400 described species in 8 families, and Tubulifera with about 3,500 species in a single family, the Phlaeothripidae. The majority of known thrips species are placed in the two largest families, the Phlaeothripidae (Tubulifera) and Thripidae (Terebrantia)  . Most sthenotoky  where unhenotoky . A numbehenotoky . MoreoveNew York .Thysanoptera  studied by the beginning of 60s of the last century. Another 7 species originating from Northeast Brazil were karyotyped by Phlaeothripidae and 11 species in 9 genera are from the Thripidae. It was unexpected to find out that thrips, unlike all other Paraneoptera insects, have monocentric chromosomes. The lowest and the highest haploid numbers of chromosomes in male thrips are 10  and approximately 50–53 , respectively. The lowest count was found in both Tubulifera ) and Terebrantia , and the highest count is found in Terebrantia, in Aptinothripsrutua . Chromosome numbers represent a nearly continuous range in each of the suborders, varying in Tubulifera from n=10 to n=15, with intermediate values 12, 13, 15 and in Terebrantia from n=10 to n=50–53, with intermediate values 14, 15, 16, 17, 18, 20, 21. In Heliothripshaemorrhoidalis  and Taeniothripsinconsequens , both from the Thripidae, different chromosome numbers were reported by different authors ; however, no information other than chromosome counts is given in the original publications  (Phlaeothripidae) originating from two isolated localities, one with n=13 and karyotype formula of n=4M+8SM+1A, and the other with n=15 and karyotype formula of n=4M+10SM+1A. G.uzeli “cytotypes”. A great variation in both number and morphology of chromosomes was revealed at family, genus and species levels, with usually no clear correlations between changes in chromosome numbers and karyotype structure. The exception seems to be the two studied representatives of the genus Gynaikothrips Zimmermann, 1900, G.uzeli (with its two cytotypes) and G.ficorum Marchal, 1908. The species status of G.ficorum remains uncertain for many years. G.ficorum is probably a form of G.uzeli, and morphological differences between different populations of these thrips can be due to different hosts and latitude. According to G.uzeli (the cytotype A with n=13) and G.ficorum (n=15) as well as differences in chromosome morphology between G.uzeli (the cytotype B with n=4M+10SM+1A) and G.ficorum (n=4M+7SM+6T) indicate that both G.uzeli and G.ficorum are distinct species and that pericentric inversions led to the differentiation of their karyotypes. It should be noted, however, that both hypotheses, especially the last one, need further research and more convincing chromosomal and also molecular confirmations.The degree of cytogenetic knowledge of thrips is negligible. Thysanoptera. It can be assumed that some species of thrips are polyploids. As mentioned above, thelytokous reproduction occurs in some species, including the greenhouse thrips, Heliothripshaemorrhoidalisis. This species was suggested to reproduce by automixis through fusion between the second polar body nucleus and the egg nucleus, so called terminal fusion , which does warrant future cytogenetic investigation    . The prer, 1854) .Coccinea  are sap-sucking phytophagous insects, among which there are many pests of agricultural and ornamental plants, as well as producers of natural dyes, lacquers and waxes. Scale insects represent a moderate-sized group of sternorrhynchous Homoptera comprising more than 8,000 species in the world fauna; they are subdivided into 19–36 recent families, depending on the taxonomic and phylogenetic views of different authors. Here, we follow the traditional system of 19 “large” families, without dividing Margarodidae, Pseudococcidae, Eriococcidae, and Asterolecaniidae into minute “families” with overlapping characters , different types of haplodiploidy , various modes of parthenogenesis, etc. (Pseudococcidae) were one of the first groups in which holokinetic chromosomes were discovered as a phenomen and studied (Planococcus spp.), have long been used as a model system to study the mechanisms underlying resistance of holokinetic chromosomes to ionizing radiation as well as the phenomenon of genome stability in holokinetic organisms  and in several species of the endemic Australian gall-inducing felt-scale genus Apiomorpha (Eriococcidae), while the highest number, 2n≈192, is found in Apiomorphamacqueeni Froggatt, 1929 (Coccinea as a whole. They prevail in large and comparatively better studied families Pseudococcidae s.l. (138 species in 50 genera), Eriococcidae s.l. (98 species in 19 genera), Diaspididae (141 species in 68 genera), Coccidae (56 species in 31 genera), and Margarodidae s.l. (39 species in 21 genera). Moreover, most studied species of the small families Dactylopiidae and Phoenicococcidae s.l. have 2n=10, and the only species of the ancient monotypic family Phenacoleachiidae, Phenacoleachiazealandica , has 2n=8. All other families are very poorly studied  or not studied at all   see .Coccidae) species Physokermeshemicryphus  and Saissetiacoffeae . We can assume that polyploidy actually occurs in scale insects more often what is indirectly indicated by that some congeneric species of soft scales, felt scales, and mealybugs differ from each other in chromosome number three or four times  (Pseudoccocidae), B-chromosomes were studied in more details  are characterized by a karyotype with 2n=10, which was found in 13 species (of the 15 studied ones) and in 19 species (of the 20 studied ones), respectively. The felt scale genus Eriococcus Targioni Tozzetti, 1868 (Eriococcidae) was found to have 2n=18 in 13 of the 18 studied species. In the family Diaspididae, which is most species-rich  and the best cytogenetically studied (141 species in 68 genera), the 2n varies from 6 to 18 but the overwhelming majority of species have 2n=8. However, there are exceptions. Some scale insect genera demonstrate a significant or even extraordinary variation of chromosome number; moreover, different diploid numbers can be found in the same nominal species. Most impressive example of such variation is the aforementioned feltscale genus Apiomorpha, where 42 diploid counts, ranging from 2n=4 to 2n≈192, have been found in 47 studied species, including undescribed ones. Moreover, extensive chromosomal variation was observed within many morphologically defined species of Apiomorpha, suggesting the involvement of chromosomal changes in the divergence of this lineage and in the generation of cryptic species  . There are known species with multiple sex chromosomes that have arisen presumably because of fissions (fragmentations) of the original X-chromosomes. Matsucoccusgallicolus Morrison, 1939 (Margarodidae) is a unique species with 12Xs in females and, thus, 6Xs in males  were reported for a bed bug species Cimexlectularius Linnaeus, 1758 (Heteroptera)  , they alCoccinea. Two species, Praelongortheziapraelonga  with 2n=16 (Ortheziidae) and the Australian felt scale Lachnodiuseucalypti  with 2n=18 (Eriococcidae), were shown to have the same number of chromosomes in both males and females. It has been reported  pair of chromosomes, which would unambiguously assume an XY system. Such an uncertain situation is usually called 2n-2n in scale insects. However, it is known that sex chromosomes can be homomorphic, with little or no divergence in size, and such examples are often found in insects, including those of Paraneoptera . Moreover, these authors also detected telomerase activity at the sites of chromosome breaks initiated by radiation in this species, which implies the possibility of de novo telomere formation at the ends of the fragmented chromosomes.Currently, there are no confirmed cases of the XY system in era e.g. . It shou females . New cytAphidinea (aphids) are a moderate-sized group of sternorrhynchous Homoptera, with approximately 5,000 described species distributed mainly throughout the temperate regions of the globe  families, which is about 22% of the total number of described aphid species , and Amphorophoratuberculata Brown et Blackman, 1985. This chromosome number was also reported for a population of Chaitophoruseucomelas Koch, 1854 (Chaitophoridae) from Peru; however, several other populations of this species sampled from Israel, Great Britain, and South Africa were found to have high chromosome numbers, 36 or 40 , Glyphina Koch, 1856 (8–55), Forda von Heyden, 1837 (18–30), Tetraneura Hartig, 1841 (10–26), Cinara Curtis, 1835 (10–22), Lachnus Burmeister, 1835 (8–38), Euceraphis Walker, 1870 (8–22), Chaitophorus Koch, 1854 (4–40), and Trama von Heyden, 1837 (8–23) . It suggests a high rate of karyotype evolution in the above species. The observed karyotype variability appeared to have no association with host plant. This is so even with the most polyphagous species, T.troglodytes, which evidences that no host race or biotype formation is occurring or even may occur in the absence of bisexual reproduction (T.troglodytes sampled from different plants have the same (or very similar) mitochondrial DNA haplotype , which has 2n=10 on barley in the northern hemisphere but 2n=8 on maize, sorghum, and Johnson grass  in all parts of the world  see . Almost ryotypes . Only inoduction . This hyaplotype . An assohe world , and in  grasses .Trama species were found to include a variable number of small mainly heterochromatic chromosomal elements. It is of interest that intraspecific changes in 2n mostly involved these heterochromatic elements but not the euchromatic chromosomes, which remain relatively stable in both number and size . In species of the genus Euceraphis and some related genera, one or more B-chromosomes, also presumably of X chromosomal origin, have also been identified or at least suggested  and the best cytogenetically studied (601 species in 119 genera) family Aphididae. These numbers or, at least, some of them are found and prevail in other relatively better studied families, including Drepanosiphidae , Eriosomatidae , and Lachnidae . Finally, in the family Hormaphididae , 2n=12 was more common than others. All other families are poorly studied without giving the opportunity to identify modal values.Karyotypes including 2n=8, 10 and 12 can be considered today as modal karyotypes for Acyrthosiphonpisum  on Fig. Insecta in general) system highlights a special “Aphidoid type” of sex determination in parallel with such unusual systems as Lecanoid and Diaspidoid known in Coccinea  sex determination. The transition between parthenogenetic and bisexual reproduction in the complicated aphid life cycle involves a number of peculiar cytogenetic processes still not studied and understood in necessary details. For example, in order for cyclical parthenogenesis to occur, all the progeny developing from fertilized eggs has to be XX female, whereas all sperm must have only one X-chromosome. This is brought about by the elimination of one of the two X-chromosomes during the single maturation division of the parthenogenetic egg what happens once a year . On the Coccinea .Trama spp, a number of other aphid species have multiple sex chromosomes originated most likely via X-chromosome fissions, although other mechanisms can also be suggested. Some species of the families Adelgidae and Greenideidae have up to four pairs of X-chromosomes, and some species of the families Phylloxeridae, Eriosomatidae, Lachnidae, and Drepanosiphidae have two pairs of sex chromosomes (see nXn/Xn(0) . Schoutedenialutea  (Greenideidae). The female karyotype of this species consists of 4 long chromosomes and 12 short chromosomes. Some embryonic cells, assumed to be male cells, showed 12 short and only 2 long chromosomes suggesting that S.lutea has 2n=12A+X1X1X2X2/X1X2 . This sex chromosome constitution, which is complex in itself, is further complicated by the fusion between sex chromosomes and a pair of autosomes leading to that the sex chromosome constitution of this species turns into an even more complex structure . The latter might be expected to persist only if it conferred some powerful adaptive advantage to the species; however, speculations on possible explanations were argued to be premature in the absence of information on male meiosis in S.lutea , known to be located on both autosomes and sex chromosomes in other holokinetic groups (see elsewhere), are located (except for a few cases) in aphids exclusively on X chromosomes and mostly correspond to the C-positive heterochromatic areas at one of their ends , this telomeric sequence was not identified  is that its telomerase is capable of producing telomeres de novo to stabilize chromosome fragments, if they arise  represent a small suborder of sternorrhynchous ld fauna . Whiteflld fauna , althougld fauna .Trialeurodesvaporariorum , n=11, Aleurotulusnephrolepidis , n=13, and for Aleyrodesproletella , n=13 and/or 14  complex sampled from 4 populations representing either sibling species or host races and/or biotypes  as is the case in some Hymenoptera species (Coccinea (see above) and in a number of other insects n n . However(TTAGG)n . In the Homoptera comprising nearly 4,000 species (in more than 200 genera) described from across every biogeographic region of the world, most of which from tropical and subtropical regions (Aphidinea), scale insects (Coccinea), and whiteflies (Aleyrodinea), psyllids feed on the phloem of vascular plants but, unlike them, they are generally oligophages restricted to one or a few closely related host plants, particularly at the larval stage. Several species are harmful to their host plants acting as vectors for various plant diseases, as economically important pests in agriculture and forestry, and as potential biocontrol agents for some invasive plants  have been investigated to date , Aphalaridae , and Triozidae, whereas other families have been relatively poorly studied.Psyllinea (jumping plant-lice) form a moderate-sized group of sternorrhynchous  regions . As withe plants . In a ree plants , as many to date . Karyotyeronidae . Most daPauropsyllatricheata Pettey, 1924 (Triozidae) comprising 2n=26A+X(0) and attributing to the fission of one pair of autosomes  , is the subfamily Rhinocolinae ; however, in this group, data are still available only for 4 species  . These lcies see .1X2Y system. Two species, Cacopsyllasorbi  and C.mali , were reported to have derived sex chromosome systems originating from one or several autosome-autosome and X-autosome fusions  (1X2Y system to be present in a polymorphic state (together with the neo-XY system) has been attributed to the high frequency of unbalanced gametes produced during meiosis in X1X2Y individuals, thus, resulting in the neo-X1X2Y system being unable to become fixed in a population  sex chromosome system is the ancestral one in Psyllinea. Several species have a neo-XY system or a neo-X fusions . In C.soulations . The neoytotype) . Both foytotype) . These fpulation .Rhinocolaaceris Linnaeus, 1758 and Cacopsyllaperegrina , have been studied in detail in terms of B chromosome distribution, C-banding pattern and behavior in meiosis. In R.aceris, B chromosomes varied in number (from one to three) in geographically distant populations and differed from each other in size, C-banding pattern and alleged origin   , as wellidoptera .Cacopsylla Ossiannilsson, 1970 (family Psyllidae), which is the most diverse genus of Psyllinea, with over 500 known species distributed throughout the Holarctic Region, and spreading into the Oriental Region  and reproduce through apomictic parthenogenesis, while rare diploids also exist. Infrequent, mainly nonfunctional, but also functional males with 2n=24A+X can be found in some populations  with apomictic parthenogenetic reproduction. No males have been recorded in C.borealis so far , is widely distributed throughout Fennoscandia, Central Europe, and Russia; it occasionally forms sympatric populations with C.borealis. Its habitats are restricted to the temperate and alpine zones. The species is triploid (2n=3x=36A+XXX) and reproduces through apomictic parthenogenesis, while infrequent functional males (2n=24A+X) can be found in some populations. In such populations with rare males, infrequent diploid females (2n=24A+XX) also exist among the triploids  have been detected in the same genus l Region . The firulations , 2015. As so far . The thiriploids . The aboCicadinea (sometimes referred to as “true hoppers”) are a large group of auchenorrhynchous Homoptera comprising more than 47,000 species distributed worldwide. The true hoppers are generally monophagous or narrowly oligophagous; many species are of economic significance acting as pests of agricultural crops and vectors of plant pathogens, including phytoplasmas, viruses, spiroplasmas, and bacteria. The two major lineages are recognized within the suborder: the infraorder Cicadomorpha comprising four superfamilies, Cicadoidea (cicadas), Cercopoidea (froghoppers and spittlebugs), Membracoidea (leafhoppers and treehoppers), and Myerslopoidea (ground-dwelling leafhoppers), and the infraorder Fulgoromorpha comprising the only superfamily Fulgoroidea (planthoppers)  with more than 12,000 described species (hoppers) . Cicadom species .Cicadinea were studied up to now n motif of telomeres  belonging to 500 genera of 31 families representing all currently recognized superfamilies of the suborder tructure . In partelomeres .Cicadinea range between 8 and 38 ; the lowest and the highest numbers are found in Cicadomorpha (Cicadellidae) and Fulgoromorpha (Delphacidae and Dictyopharidae), respectively. Despite the fact that since 2015 new data have appeared, the above series has remained unchanged. Chromosome numbers exceeding 38, when reported, are all related to parthenogenesis  and accompanying polyploidy. For example, up to 45 chromosomes have been found in pseudogamous triploid females of Muellerianellafairmarei Perris  to 38 , with strongly marked mode at 28 and the second and the third modes at 30 and 26, respectively. In Cicadomorpha, 2n varies from 8  to 32 . Most species have 2n between 20 and 28, other counts being rare. Specifically, in Cercopoidea 2n varies between 14 and 32, with the mode at 26–28; in Cicadoidea between 12 and 20, with the mode at 20; in Membracoidea between 8 and 28, with the mode at 22 , has 2n=16+XY. The XY system in this species is most likely of a neo-XY type and indicates the derivative nature of the karyotype, which could be a result of a fusion between the original X and an autosome in the original karyotype of 2n=18+X(0)  .Cicadinea show stable or only slightly variable karyotypes. Quite often, the chromosome number is constant within the genus and even within the family suggesting that fusion/fission events were rare in their evolution. Supporting examples can be found in the review of Dictyopharidae and Issidae (Fulgoroidea), and the cicada genus Magicicada Davis, 1925 . The family Dictyopharidae is one of the largest families of planthoppers worldwide, with 720 valid species and 156 valid genera at present (Dictyopharinae and Orgeriinae. The karyotypes are known in 18 species (7 genera) of the first subfamily and in 29 species (17 genera) of the second subfamily. In Dictyopharinae, the tribe Dictyopharini (with about 14% of species and genera studied) is characterized by 2n=28A+X(0) in males. Within Orgeriinae, the most primitive tribe Ranissini  and one of the most advanced tribes, Orgeriini (about 7% and 20%), show 2n=26A+X(0) in all the species studied. The tribe Almanini (about 20% and 60%) is characterized by 2n=24A+neo-XY. Available data suggest that the ancestral karyotype of the Dictyopharidae included 2n=28A+X(0) and karyotypic transformations in the evolution of the family occurred mainly by fusion of chromosomes , found in all but three studied species. The basic issid karyotype appears also conservative in structure. Every species was shown to have a very large pair of autosomes that also carry rDNA clusters what has been confirmed by both different chromosomal staining techniques (AgNOR banding and DNA-binding fluorochrome CMA3) and rDNA-FISH. The newly obtained data support, thus, the hypothesis that the karyotype of 2n=26A+XX/X(0) has the monophyletic origin and represents an ancestral character state for the family Issidae in general  and Brahmaloka sp. were shown to have 2n=24A+X, whereas males of Falcidiuslimbatus  were found to have 2n=24A+neo-XY. Both derived karyotypes could have arisen by a single tandem fusion in the ancestral karyotype of 2n=26A+X, the first between two pairs of autosomes resulting in 2n=24A+X, and the second between an autosome and the X resulting in 2n=24A+neo-XY. The genus Magicicada (Cicadidae) inhabiting eastern United States and comprising the periodical cicadas remarkable for their 17- or 13-year synchronized life cycles and periodical mass emergence of adults, has 2n=18A+XX/X(0) in all the seven recognized species , which were thoroughly studied using different methods and approaches n telomeric probes), it was possible to trace almost all successive evolutionary stages of sex chromosome transformations  (The XX/X(0) sex determination is of common occurrence and seems to be an ancestral trait in both icadinea , 1992 anicadinea . Despiteicadinea . In a rermations , 2013. Agoridae) . It seemCicadinea. We can anticipate that it is due to very few studies at the population level in this group (like in other Paraneoptera). However, some examples of polymorphism for B-chromosomes and for fission/fusion events have been described in natural populations of both leafhoppers and planthoppers , a full range from 2n=12 to 2n=20 was reported for only 19 studied species. The cosmopolitan genus Empoasca Walsh, 1862 with more than 800 nominal species  are a very diverse group in terms of habitats  and feeding habits   . Severalphagous) . Heteroplomorpha .Heteroptera dates back to the end of the 19th century when German biologist Hermann Pyrrhocorisapterus Linnaeus, 1758 (Pyrrhocoridae), which he designated in his drawings by “x” . Since this great discovery, the following key developments have occurred in true bugs cytogenetics. In the period from 1905 to 1912, T.H. Montgomery and E.B. Wilson published a series of papers that actually marked the beginning of true bug cytology  and the so-called sex chromosome “post-reduction” in male meiosis when sex chromosomes undergo equational division at anaphase I and reductional division at anaphase II, make true bugs unique among Paraneoptera and even among Insecta in general. The above monograph also contains a comprehensive check-list of chromosome numbers and sex chromosome systems known at that time for all heteropteran infraorders with the exception of Enicocephalomorpha, for which information is lacking to this day. Since Heteroptera, and a review by Heteroptera has been obtained. Heteroptera as a whole. According to this comprehensive review, heavily based on Ueshima’s list, data were available for approximately 1,600 species belonging to 46 true bugs’ families. Although the data set seemed to be impressive, the number of studied species by 2006 was no more than 4.2% of described true bug species. The authors have argued that chromosome numbers in true bugs vary from 2n=4 to 2n=80 but about 70% of the species have 12 to 34 chromosomes, with male diploid number of 14 being the most represented; sex chromosome mechanism is predominantly of the XX/XY type (found in 71.4% of studied species), but other variants such as an XX/X(0) system (14.7%), multiple sex chromosome systems such as XnXn /XnY, XnXn/Xn(0), and XX/XYn (13.5%), as well as neo-sex chromosomes (0.5%) also occur. The main mechanisms of karyotype evolution in true bugs were argued to be fusions between autosomes, fusions between the X and an autosome, and fissions involved both autosomes and sex chromosomes. It is generally accepted that multiple sex chromosome systems in Heteroptera are the result of sex chromosome fissions (fragmentations)  . This isulations , b. It htularius . In sometularius .Heteroptera has been actively debated. Two alternative hypotheses supported by different sources of evidence have been proposed. One of these holds that the XY system has evolved from an X(0) system , was the evolutionarily initial in the ) system  while th) system . Last lier, 1860 .Dipsocoromorpha, Nepomorpha, Leptopodomorpha, and Pentatomomorpha), a pair of so-called “m-chromosomes”, has been described , m-chromosomes were shown to undergo normal synapsis at pachytene assuming the chiasma formation  polymorphic for the presence/absence of an extra chromosome. In the studied population, males with 2n=22(20A+XY) coexisted with males displaying 2n=23(20A+XY) + extra chromosome. The meiotic behavior of the extra chromosome was highly regular and similar to that of sex chromosomes. Using various cytogenetic approaches combined with a morphometric analysis of chromosomes, the authors concluded that this extra chromosome was an additional X chromosome rather than a B-chromosome  to 2n=80  as reported by Gerromorpha, in which the number of studied species has more than doubled (51 against 21), although enriched with new interesting data (Fairbairn 2016), can still be seen as a group only slightly varying in chromosome number, with predominantly XX/X(0) sex determination and the absence of m-chromosomes . Then, Reduviidae, at least, the kissing bug subfamily Triatominae and the largest reduviid subfamily Harpactorinae, have the insect-type (TTAGG)n motif of telomeres. It should be noted that in true bugs this motif was first identified in Lethoceruspatruelis  from the family Belostomatidae, Nepomorpha  were shown to differ from one another in chromosome number and sex chromosome systems; besides, interstitial telomere sequences (ITS) found in some species were interpreted as signs of telomere-telomere fusions that took place in the evolution of the genus  was found to have a conventional pre-reductional division of sex chromosomes in male meiosis, what distinguishes it from all other studied species of this family  are the only true bug family showing this meiotic pattern in all hitherto studied species , A.murcius Nieser et Millán, 1989, and Aphelocheirus sp. (from northern Spain), were shown to have the same karyotype, 2n=22+XX/X(0) . For example, within the largest evolutionarily advanced and highly diversified infraorder dae e.g. , 2019a, Tingidae , 2018; Ndae e.g. . Specifi Nabidae . The datpomorpha , and allTingidae , 2018 iton e.g., . Specieshe genus . In the  species , 2018. R(Nepidae . At the +XX/X(0) .Coleorrhyncha (moss bugs or peloridiids) are little-known insects believed to be relict members of an ancient lineage of Hemiptera (Coleorrhyncha have been variously assigned to the Heteroptera or to the Homoptera since they possess a mixture of cicadomorphan and bug-like characters (Peloridiidae) of the separate suborder Coleorrhyncha, which is treated as the sister group to the Heteroptera  and 33(2n=32A+X) holokinetic chromosomes, respectively  clearly prevail. One or both systems are present in every major lineage, with rare exceptions where sex chromosomes either not identified or really absent . The X(0) system has been recognized by different authors as the ancestral one for a number of groups including the most basal Copeognatha, and it appears to be an attractive candidate for the ancestral sex chromosome system for Paraneoptera clade in general , HomopteraCoccinea , HomopteraAphidinea , and Heteroptera . On the other hand, the highest count is found in the only scale insect species, Apiomorphamacqueeni. The genera Apiomorpha (Coccinea) and Amphorophora (Aphidinea) are unique showing the most extensive chromosome number variability known among Coccinea and Aphidinea, respectively: in the first, 2n ranges from 4 to 192 (48-fold variation) and in the second, 2n ranges from 4 to 72 (13-fold variation). These examples suggest a high rate of chromosome evolution in Apiomorpha and Amphorophora and the potential for holokinetic chromosomes to break and fuse. It’s amazing that within Apiomorpha, as many as 42 chromosome counts have been reported for 47 species studied to date. It is important to note that both scale insects and aphids display very diverse and often very peculiar reproductive modes, including different types of parthenogenesis that may enable rearranged karyotypes to persist and potentially contribute to speciation events. However, all other Aphidococca as well as all other holokenetic groups of Paraneoptera display comparatively low chromosome numbers and rather little chromosome number variation at different taxonomic levels. The only other exception to this rule known today in Paraneoptera is the plant bug genus Lopidea  showing 2n=80 in each of the four studied species.With only the intriguing exception of ral Fig. . ParaneoParaneoptera is not very pronounced; it does not differ significantly from the variability observed in monocentric insects, including monocentric Thysanoptera  where 2n ranges from 20 to 100–106 (5-fold variation) in the only 17 studied species. It is worth mentioning in this regard that some other non-polyploid monocentric animals can also have high chromosome numbers as well as between-and within-species chromosome number variation (e.g. The currently available data suggest that the chromosome number variability in holokinetic groups of ion e.g.  includinion e.g. .The significance of chromosomal rearrangements and mechanisms underlying differences in chromosome number have been debated for many years e.g. . HoweverParaneoptera supports the trends that have been seen by Paraneoptera insects.As noted in the Introduction,