The coronavirus disease (COVID-19) has already been declared a global pandemic. To our knowledge, there is very little information regarding the effects of COVID-19 on women seeking reproductive health services, specifically abortion. This study was aimed to assess the impact of the COVID-19 pandemic on reproductive and sexual health among women seeking abortion services. We conducted a series of preliminary analyses using data collected from ten maternal and child health hospitals of seven provinces in China before and during the COVID-19 lockdown. The present study showed that a significant decrease was observed in the frequency of sexual intercourse during the COVID-19 pandemic. Moreover, a significant increase in contraceptive use including condom, rhythm method and coitus interruptus whereas a decrease in choosing oral contraceptives were observed during the COVID-19 pandemic. In addition, the pandemic was associated with increased intention of seeking induced abortion due to social factors. Future research should look into the long-term impact of the COVID-19 pandemic on sexual and reproductive health. Even China had a sound drug supply system, contraceptives in some areas were out of stock or in short supply during the pandemic3.As an event that can cause physical, emotional, and psychological harm, the COVID-19 pandemic may affect sexual and reproductive health of individuals. From the end of January 2020, people in China were required to implement “social distancing” and restricted to step outside homes except for essential activities, and public transport was suspended6. Studies have showed that many women are unable to obtain family planning services in order to avoid unwanted pregnancies during some other public health emergencies8. Meanwhile, women’s sexual activity and contraceptive use may have to adapt under these unprecedented conditions. They may lose support and comfort during the pandemic because of social isolation from friends and relatives9. To our knowledge, there is very little information regarding the effects of COVID-19 on women seeking reproductive health services, specifically abortion.In addition, many provinces have implemented guidelines to reduce pressure on the health care system, including the suspension of nonemergency medical care and elective surgeries. Thus many hospitals have reduced or stopped provision of reproductive health services during the COVID-19 pandemic. These restrictive social measures that are important for the COVID-19 control but restrictions in movement, social isolation and lack of availability of reproductive health services could lead to reduced access to abortion services and could have a profound influence on sexual and reproductive healthThis study was aimed to assess the impact of the COVID-19 pandemic on reproductive and sexual health among women seeking abortion services. We conducted a series of preliminary analyses using data collected from ten maternal and child health hospitals of seven provinces in China before and during the COVID-19 lockdown.This study was based on our prospective multicenter cohort study to evaluate effects of prior induced termination of pregnancy on complications and pregnancy outcomes . The cohort study is ongoing but as yet unpublished. Women who experienced induced abortion in early pregnancy (< 12 weeks of gestation) were included in this study from May 2019 in ten maternal and child health hospitals of seven provinces in China. No other specific inclusion or exclusion criteria were used. For the present study, data from the cohort were extracted. For each participant, a detailed medical history was obtained, including age, nationality, marital status, education, and household income. Other details recorded were frequency of sexual intercourse, contraceptive use in sexual encounters, reasons for abortion and the choice of abortion methods. All data were recorded prospectively in the electronic data system.To assess the impact of the COVID-19 pandemic on women seeking abortion services and their reproductive and sexual health, we conducted an observational study using previously collected data from our cohort study described above to compare the demographic characteristics, frequency of sexual intercourse, contraceptive use in sexual encounters, reasons for abortion and the choice of abortion methods before  and during the COVID-19 lockdown .All participants provided written informed consent first and for participants under the age of 18 years, informed consent was obtained from a parent and/or legal guardian. This study was approved by the Ethics Review Committee of National Research Institute for Family Planning. All methods were performed in accordance with the relevant guidelines and regulations.2 tests to compare demographic and clinical characteristics of participants before and during the COVID-19 lockdown. We also used multivariable logistic regression to estimate odds ratios (ORs) and 95% CIs for the association between the COVID-19 pandemic and frequency of sexual intercourse, controlling for demographic characteristics; the model controlled for age, marital status, education and household income. Two-sided P < 0.05 was used to test statistical significance. We excluded missing data from all analyses, but denominators were provided to put these missing data into context. All analyses were performed using SPSS Statistics version 23 (IBM).Descriptive statistics were performed on the variable of interest. We used χP < 0.001). Similarly, before COVID-19, 1371/2051 (66.8%) were married, but this rised to 1325/1729 (76.6%) during lockdown (P < 0.001). Education levels were higher among the participants during the COVID-19 lockdown compared with the pre-COVID-19 sample . But the sample during the COVID-19 lockdown had a lower income than the pre-COVID-19 sample .A total of 3789 participants were included in the analysis. Of these, 2054 participants  were included in the pre-COVID-19 sample  and 1735 participants  were included in the sample during the COVID-19 lockdown . Table P < 0.001). Multivariable logistic regression showed that after controlling for age, marital status, education and household income, participants during COVID-19 lockdown had 2.878-fold increased odds of low sex frequency  compared with participants before COVID-19 lockdown (OR 2.878 [95% CI 2.485–3.332]) (Table P < 0.001). Of these women choosing contraception, the proportion of choosing condom, rhythm method and coitus interruptus during COVID-19 lockdown are significantly higher when comparing with those of the pre-COVID-19 sample . Conversely, fewer women chose oral contraceptives during COVID-19 lockdown than the pre-COVID-19 sample .Sexual activity and choice of contraceptive methods before and during COVID-19 lockdown are presented in Table P < 0.001). No statistical differences were observed in choice of abortion methods before and during COVID-19 lockdown (P = 0.360). Most women chose surgical abortion (Before COVID-19: 1742/2003[87.0%] vs during COVID-19: 1492/1696[88.0%]) rather than medical abortion (Before COVID-19: 261/2003[13.0%] vs during COVID-19: 204/1696 [12.0%]).Table 11. An online survey in China showed that 44% of participants reported a decrease in the number of sexual partners and about 37% of participants reported a decrease in sexual frequency during the COVID-19 pandemic10. Fuchs et al. also found that during the pandemic, the frequency of sexual intercourse declined compared to the period before11. There are two main reasons which may account for these findings. First of all, quarantine made it harder to reach the preferred sexual partner during the pandemic. Furthermore, women’s stress about a possible pregnancy due to the fear of economic instability and lack of knowledge of pregnancy outcomes related to the COVID-19 infection might lead to the decreased desire for sexual intercourse. However, a recent study conducted in Italy reported no reduction in frequency of sexual intercourse during the COVID-19 pandemic, with no significant differences among genders12. In comparison, another study conducted in Turkey found that the COVID-19 pandemic is associated with increased sexual desire and frequency of intercourse, whereas quality of sexual life significantly decreased13.This study provided preliminary evidence of the impact of the COVID-19 pandemic on the sexual and reproductive health of women with induced abortion. According to the data obtained from the study, as the proportion of participants aged over 35 years, married, with a college degree or above increased during the COVID-19 pandemic, a decrease in the frequency of sexual intercourse was observed. Moreover, the participants during COVID-19 lockdown had 2.878-fold increased odds of low sex frequency  compared with participants before COVID-19 lockdown (OR 2.878 [95% CI 2.485–3.332]). These findings partly corresponded to previous studiesP < 0.001). Of these, more women chose condom, rhythm method and coitus interruptus during COVID-19 lockdown  whereas fewer chose oral contraceptives . Limited public transport and fear of contracting the virus during the lockdown may result in delays in seeking oral contraceptive in a pharmacy. Meanwhile, the distribution of oral contraceptives to retail sellers may be impacted by the suspended transportation between cities during the lockdown. Li et al. found that even in a country with a sound drug supply system such as China, there were still a shortage of contraceptives in some areas during the pandemic3.Our study also demonstrated that there was a significant increase in the rate of participants using contraceptive methods during the pandemic . Childbirth, as one of the most important events in a person’s life, is naturally associated with a certain level of worry. Yet, as evidenced by our results, abortion due to social factors soared during the pandemic, indicating that the pandemic has the potential to increase additional stress in the pregnant population. This finding is in agreement with two recent studies. A large-scale longitudinal survey conducted in Sweden showed that the worries of pregnant women about their own health, as well as their child’s health remained at higher than usual levels during the pandemic14. A cross-sectional study conducted in Iran also revealed that because of social stress and anxiety, pregnant women want to terminate their pregnancies prematurely15.In addition, we found that the proportion of women seeking abortion due to social factors increased significantly during the pandemic (1349/1700[79.4%] vs 1275/1999[63.8%];We are aware that the COVID-19 pandemic is a period when countless factors might have an impact on many different aspects of human health, including sexual and reproductive health. Much attention of health workers is focused on infectious diseases and symptoms during the pandemic. From the results of this study, it is suggested that more attention should be paid to sexual and reproductive health in such an unusual situation and targeted interventions are needed to improve sexual health in addition to the physical and mental health of individuals. Additionally, the stakeholders need to take actions to guarantee a convenient access to basic reproductive health services for pepole in childbearing age during the pandemic. Moreover, telemedicine can play a significant role to facilitate contact between patients and physicians in case future pandemics or similar events may happen.This study has some limitations. First, we compare the pre-COVID-19 sample and the sample during the COVID-19 lockdown rather than the same individuals over time so the pre-COVID-19 sample can provide only a proxy for the true baseline level for the sample during the COVID-19 lockdown. Further limitations include recall bias and missing data for several variables as not everyone completed all questions. While our study reaches a broad sample, it is concentrated in city areas in China and the COVID-19 pandemic is peaking in different cities at different times. This may represent a relative bias of selection. This study was not designed to assess regional differences. Finally, the study has not determined the long-term impact of the COVID-19 pandemic on sexual and reproductive health; this must be realised in subsequent cohort analyses of future waves of data.To our knowledge, this may be the first study among women with induced abortion on sexual health during the COVID-19 pandemic. The present study showed that a significant decrease was observed in the frequency of sexual intercourse during the COVID-19 pandemic. Moreover, a significant increase in contraceptive use including condom, rhythm method and coitus interruptus whereas a decrease in choosing oral contraceptives were observed during the COVID-19 pandemic. In addition, the pandemic was associated with increased intention of seeking induced abortion due to social factors. These findings demonstrate that the pandemic dramatically affects sexual health among women. Basic reproductive health services and contraceptives supply chain operations should be guaranteed to protect the rights and health of women during the COVID-19 pandemic. Future research should look into the long-term impact of the COVID-19 pandemic on sexual and reproductive health.


The review explores the findings of previous studies to elucidate the association between levels of D-dimer and COVID-19 severity and prognosis. In addition, we assessed the efficiency of anticoagulant therapies in reducing COVID-19 severity and improving the prognosis of the patients.  A comprehensive literature review was conducted using MEDLINE/PubMed databases, Scopus, and Web of Science with the help of keywords “COVID-19,” “D-Dimer,” “Thrombosis,” “Fibrin network,” “Anticoagulant therapy,” “Inflammation,” and “disease severity.” Based on all these articles and clinical experience, a scoping review was constructed and the full texts of the articles that were retrieved were accessed.  A D-dimer is a complex protein molecule that is formed during plasmin-mediated degradation of the fibrin network. Thus, it serves as a marker of thrombotic activity. On the other hand, in addition to severe respiratory distress and reduction in pulmonary gas exchange, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) also triggers prothrombotic changes in the infected individuals. The levels of D-dimer have been postulated to be positively associated with the degree of disease severity among COVID-19 patients.  It has been postulated that D-dimer could potentially be used as a biomarker to predict the prognosis and outcome of COVID-19 patients at the time of admission to hospitals and facilitate more personalized and efficient clinical management that could significantly reduce the mortality rate of such patients and allow more rapid recovery. Later, this outbreak was declared a global pandemic by 12th March 2020 [The first case of coronavirus disease 2019 (COVID-19) was reported in December 2019 in the Wuhan province of China. After that, it quickly spread across 200 countries within a span of a few months. Global research efforts quickly identified the etiological agent of this disease to be a novel coronavirus. This novel coronavirus exhibited approximately 80% homology to SARS-CoV, which had earlier spread during 2002–2003 and was associated with acute respiratory distress syndrome (ARDS) and a high mortality rate [The novel coronavirus primarily transmits via respiratory droplets. The angiotensin-converting enzyme 2 receptor present on the cell surfaces plays a key role in the invasion of the novel coronavirus . Most ofA comprehensive literature review was conducted using MEDLINE/PubMed databases, Scopus, and Web of Science with the scope of the searches confined to English language sources. There was no time restriction specified since the items on COVID-19 continue to accumulate on a regular basis. Priority was given to articles with a stronger evidence base, even though all types of articles were examined. The following keywords were employed: “COVID-19,” “D-Dimer,” “Thrombosis,” “Fibrin network,” “Anticoagulant therapy,” “Inflammation,” and “disease severity.” In general, we followed the guidelines for producing scoping reviews that were provided to us.A D-dimer is a complex protein molecule that is generated during plasmin-mediated cross-linked fibrin degradation. The generated plasmin molecules, in turn, bind with the fibrin molecules and mediate degradation of the bound fibrin into products with different molecular weights, commonly known as fibrinogen degradation products (FDPs). Plasmin also mediates terminal degradation of the cross-linked fibrin molecules into soluble fragments that contain DDE fragments. A DDE fragment, simply put, is a D-dimer molecule that is noncovalently bound to fragment E. The plasmin molecule further breaks down the DDE fragment into DD and E fragments. The D-dimer (DD fragment + E fragment) is a soluble complex and circulates in the plasma until it is eliminated by the reticuloendothelial and renal pathways . It is nFibrin monomers are generated after the degradation of a fibrinogen molecule by thrombin. The generated fibrin monomers then bind to other fibrin or fibrinogen molecules, which results in the formation of protofibrils. The dotted lines between the D-E domain and the D domain depict the noncovalent interactions that aid in maintaining the structural integrity of the protofibrils.Simultaneously, thrombin activates the formation of plasma factor XIIIa that binds to the D-domains of the fibrin polymers via covalent interactions.Then, fibrin degradation products (FDPs) are formed after the disrupting action of plasmin on multiple sites of fibrin, which, in turn, exposes the D-dimer antigen epitope. These FDPs are then further degraded, resulting in the formation of a terminal DDE complex .There are three major steps of D-dimer formation:The fibrinolytic system is responsible for the prevention of the formation of fibrin thrombi. Such thrombi are mainly composed of fibrin polymers and, under normal circumstances, they are disrupted by the fibrinolytic system as soon as they are generated. Currently, such FDPs are the most widely used biomarkers of thrombosis. Several modulators play a key role in the promotion (such as tissue plasminogen activator and TPA) or prevention (such as thrombin activatable fibrinolysis inhibitor) of fibrin degradation. As abovementioned, the DDE fragment (D-dimer) only generates when plasma factor XIII degrades the fibrin polymers. Thus, this fragment holds great potential as a biomarker of fibrin degradation and coagulatory pathways and, in turn, thrombosis .μg/mL to be a potential risk factor of COVID-19 [Since its emergence, several investigators around the globe have published a plethora of studies on the epidemiology of COVID-19. Although its transmittance rate is extremely high, it has a very low mortality rate of 2.3% . A higheCOVID-19 . The forCOVID-19 , 15. TheCOVID-19 . PreviouCOVID-19 .It is noteworthy that the proinflammatory cytokines are involved in both inflammatory and coagulatory processes. Previous studies have shown that severe infection of novel coronavirus triggers severe inflammatory reactions, as indicated by the significant upregulation of proinflammatory cytokines . The cytAs stated above, the levels of D-dimer directly correlate with the rate of formation and degradation of plasmin. Hence, any pathological condition that upregulates the rate of plasmin generation and degradation would also increase the levels of D-dimer. Thus, the pathologies that promote chronic inflammation, such as rheumatoid arthritis, asthma, and cancer, also lead to an increase in the levels of D-dimer. It follows that infection of a novel coronavirus, which leads to upregulated inflammatory reactions among individuals, would also increase the levels of D-dimer. This is evident by the findings of several previous studies that showed that levels of D-dimer were significantly higher in COVID-19 patients, especially those who were either severely ill or had deceased , 24. Somp=0.002) [In 2020, Guan et al. presented the results of a large retrospective study that indicated the correlation between abnormal levels of D-dimer and disease severity of the COVID-19 patients for the first time . Settingp=0.002) . Furtherp=0.002) . Their rp=0.002) , 24. In p=0.002) , 27.In a recent study, Lippi and Favaloro observed that the levels of D-dimer of the COVID-19 patients with a mild or moderate level of illness, that is, those who did not require ICU admission, were significantly lower than the levels of D-dimer of the patients with a severe level of illness, that is, those who required ICU admission . In anotThe novel coronavirus infection leads to upregulation of the inflammatory pathways. According to the results of several previous studies, the abnormal increment in the levels of D-dimer under inflammatory conditions indicates that the upregulation of inflammatory reactions and proinflammatory agents might be associated with the induction of the coagulatory pathways . Hence, Considering the COVID-19 pandemic, identifying therapies that improve outcomes is crucial. The findings presented in this review indicate that D-dimer could prove to be a potential biomarker to assess the disease severity level of COVID-19 patients and predict their outcome. This postulate is further supported by the analysis of Sakka et al., who suggested that levels of D-dimer could be helpful in categorizing the COVID-19 patients in terms of their disease severity levels at the time of admission to the hospital itself. They further reported that such categorization of the patients could facilitate personalized and more efficient clinical management in a timely manner based on their disease severity level . FurtherHeparin: In their recent retrospective review, Tang et al. assessed the effect of heparin therapy on the mortality rate of COVID-19 patients. They reported that, overall, there was no significant difference in the mortality rates of COVID-19 patients who either received or did not receive heparin. However, the COVID-19 patients with abnormally high levels of D-dimer who received heparin exhibited significantly lower mortality rates than the COVID-19 patients with abnormally high levels of D-dimer but who did not receive heparin. The former result could be attributed to the fact that other clinical settings and treatment modalities received by the patients were not revealed, impacting the mortality of the COVID-19 patients , 56.TPA: Although to date very few studies have assessed the effects of TPA administration on mortality rates of COVID-19 patients, their results have been positive. These studies have reported significant improvement in the ventilator parameters and oxygenation index of severely ill COVID-19 patients after TPA administration .Direct oral anticoagulants (DOACs): This category of anticoagulants seems to be effective in COVID-19 patients based on the findings of Testa et al. who reported a marked increment in the plasma levels of DOAC in COVID-19 patients who received antiviral medications .Currently, the COVID-19 patients are managed using pharmacological DVT prophylaxis. However, this management approach is not specific to COVID-19 patients . AcutelyA recent study published by Spyropoulos et al. reported that the use of therapeutic-dose low molecular weight heparin (LMWH) for thromboprophylaxis in high-risk inpatients with COVID-19 decreased thromboembolism and mortality in their trial. High-dose anticoagulant therapy altered the course of illness in patients who were not in the intensive care unit but had a very high risk of thromboembolism and mortality (36.1% incidence in the standard dose group) .In conclusion, it is clearly evident that levels of D-dimer are directly associated with the disease severity among COVID-19 patients. Novel coronavirus infections promote inflammatory and coagulation reactions, leading to an increase in thrombotic event rates. Currently, the evaluation of levels of D-dimer has not been adopted in the routine laboratory assessment of COVID-19 patients. Laboratory testing for D-dimer and proinflammatory cytokines could help to categorize the COVID-19 patients based on the severity of their illness. This could, in turn, be helpful in adequate and more efficient management of such individuals. We also recommend that future investigators should focus on conducting more comprehensive and multicentric prospective studies to elucidate further the association of levels of D-dimer with the levels of proinflammatory cytokines and with the thrombotic pathways, especially in COVID-19 individuals. Finally, we propose that physicians should consider using anticoagulant therapies to counter the upregulated thrombotic activity in COVID-19 patients.


The COVID-19 pandemic has negatively impacted sporting activities across the world. However, practical training strategies for athletes to reduce the risk of infection during the pandemic have not been definitively studied. The purpose of this report was to provide an overview of the challenges we encountered during the reboot of high-performance sporting activities of the Japanese national handball team during the 3rd wave of the COVID-19 pandemic in Tokyo, Japan. Twenty-nine Japanese national women’s handball players and 24 staff participated in the study. To initiate the reboot of their first training camp after COVID-19 stay-home social policy, we conducted: web-based health-monitoring, SARS-CoV-2 screening with polymerase chain reaction (PCR) tests, real-time automated quantitative monitoring of social distancing on court using a moving image-based artificial intelligence (AI) algorithm, physical intensity evaluation with wearable heart rate (HR) and acceleration sensors, and a self-reported online questionnaire. The training camp was conducted successfully with no COVID-19 infections. The web-based health monitoring and the frequent PCR testing with short turnaround times contributed remarkably to early detection of athletes’ health problems and to risk screening. During handball, AI-based on-court social-distance monitoring revealed key time-dependent spatial metrics to define player-to-player proximity. This information facilitated appropriate on- and off-game distancing behavior for teammates. Athletes regularly achieved around 80% of maximum HR during training, indicating anticipated improvements in achieving their physical intensities. Self-reported questionnaires related to the COVID management in the training camp revealed a sense of security among the athletes that allowed them to focus singularly on their training. The challenges discussed herein provided us considerable knowledge about creating and managing a safe environment for high-performing athletes in the COVID-19 pandemic via the Japan Sports–Cyber Physical System (JS–CPS) of the Sports Research Innovation Project . This report is envisioned to provide informed decisions to coaches, trainers, policymakers from the sports federations in creating targeted, infection-free, sporting and training environments. The COVID-19 outbreak and the associated home confinement strategy have significantly altered not only the daily lives of the general public, but also the sporting activities of athletes . The negWith viral transmission mechanisms becoming clearer, preventive measures have become the mainstay of addressing individual-level risk control . HoweverHandball is an indoor, contact sport in which two teams pass a ball using their hands, aiming to throw at the goal of the opponent team. The sport requires an intermittent repetition of aerobic and anaerobic demands during games, resulting in a high respiratory rate in such athletes . The WHOThe conceptualized control strategies/guidelines in elite sports and sporting events were widely announced in 2020 ,14,15. SWe evaluated 29 Japanese national women’s handball players and 24 staff members . This research was performed in accordance with all relevant guidelines and regulations as well as the Declaration of Helsinki. The purpose of the study was explained to all participants using documents authorized by the JHA and the ethics committee of the Osaka University Hospital (19537-2). Written informed consent was obtained from all participants. Every athlete was a domestic player at the time of testing. Their home teams were from Kumamoto, Kagoshima, Ishikawa, Osaka, Mie, Tokyo, Ibaraki, and Hiroshima prefectures and travelled to Tokyo on 24 November 2020 after confirming COVID-19 negative status with precamp PCR testing as described below. None of the athletes and staff members were vaccinated before the beginning of the training camp.On 24 March 2020, the Japanese government announced the postponement of the Tokyo Olympics and Paralympics, followed by the declaration of a state of emergency on 7 April. As a result, the Japanese national handball team canceled all training schedules from April to August, specifically, all domestic competitions, three domestic training camps , and an international training trip in three European countries (May–June). During this period, the national team players continued to train themselves under restricted conditions, basically at their home teams, with some discrepancies among the teams. The regular handball training gathering all team members was basically canceled from April to June 2020. Instead, team members practiced handball in small groups of three to five players. They also continued individual endurance, agility, and resistance training. The team physical coach remotely instructed the individualized training during the period of restricted activity. After the Japanese government declared the end of the state of emergency on 25 May, each home team resumed regular handball practice in stages until the end of July. Therefore, by the time the national team’s first training camp after COVID-19 began on 24 November 2020, each national team player had been conducting regular handball practice for about four months.The training camp was held at the Ajinomoto National Training Center (ANTC) in Tokyo. The ANTC is a national sports complex designated for high performance sports. This was the first time a training camp of this scale was organized after Japan’s COVID-19 state of emergency and “stay-home” social policy. The 2-week camp started on 24 November 2020 and was completed on 8 December 2020. The reboot of the camp was approved by the Japan Olympic Committee (JOC), the JSA, and the Japanese Ministry of Health, Labor, and Welfare (MHLW) based on well planned regulations within the training halls and emergency protocols prepared by the JHA in advance. The health requirements to participate in the camp were the lack of a fever above 37.5 °C in the past two weeks and a negative PCR test conducted four days prior to the camp admission. On day 1, all players and staff were briefed by the JHA with reference to the protocols for team compliance during the training camp. The training plan was designed by the head coach to enhance athletes’ physical capabilities, handball skills, and tactics. It consisted of twenty training sessions including handball practice, training matches, weight training, functional movement training, physical performance tests, and medical checkups.The scientific monitoring was jointly carried out by the JHA, the Osaka University, and the Japan Sports Agency (JSA) leading the activity of the JS–CPS  of the Sports Research Innovation Project .All athletes documented their body temperature, body weight, and subjective health conditions every day via a web-based system . In early morning, athletes measured their axillary temperatures with their thermometers in bed immediately after waking up. Monitoring duration was from 10 November to 22 December 2020 (2 weeks before and after the training camp). When body temperatures above 37.5 °C were reported, the system alerted the medical staff via email regarding the corresponding athlete’s status.https://www.niid.go.jp/niid/images/lab-manual/2019-nCoV-17-current.pdf (Japanese document) accessed on 28 August 2021].A total of 10 PCR testing sessions (364 samples), which included precamp screening and in- and postcamp inspection, were performed. Saliva samples were examined by a SARS-CoV-2 Direct Detection RT-qPCR Kit  using a LightCycler 96  for the detection of SARS-CoV-2 according to the methods described by the manufacturers. The specificity (100% = 10/10 positive samples detected) and the sensitivity (100% = 15/15 negative samples detected) of the SARS-CoV-2 Direct Detection RT-qPCR Kit were confirmed by the National Institute of Infectious Diseases (NIID), Japan [Precamp screening and postcamp verification.Each individual sampled their saliva (1 mL) at their residence under the online guidance of the researcher (I.O) on 19 November and 9 December, thereby providing pre- and postcamp samples, respectively. The centrifuge tube (primary packaging) containing saliva was wrapped with an absorbent sheet and tightly sealed in the biopouch (secondary packaging). The sample was then placed in a bio-mailer box (tertiary packaging) and sealed with a security sticker. Finally, the bio-mailer box was put into a quaternary packaging box. This box was then transported under the regulation of MHWL  to the Group of Infection Control and Prevention (G-ICP) in Osaka University Hospital via Japan Post Co., Ltd., Tokyo, Japan. The results of pre- and postcamp PCR screening  were reported to JHA via email.SARS-CoV-2 PCR testing protocol in the camp at ANTC.During the camp period (from 24 November to 8 December), SARS-CoV-2 PCR testing was conducted every Monday, Wednesday, and Friday  . On the The degree of social distancing on the handball court was monitored by a custom-made AI system . The sysTo quantify the intensity of physical activity, we used a wearable sensor that measured heart rate (HR) and truncal acceleration. The purpose of this recording was to evaluate whether the physical demands on each player were high enough to enhance their performance. Athletes wore electrodes sewn onto sports bras with a small wearable sensor  to record the electrocardiogram (ECG) and three-dimensional acceleration of the torso at 200 Hz. Truncal (3D) accelerometer data was used only to define the active phases during the training matches. The HR measurements were performed during a 3000 m high-intensity endurance time trial test (30 November) and during eight training matches . Given the physically demanding nature of the 3000 m time trial test, we used the HR max value obtained during the 3000 m run as a surrogate marker to evaluate the physical intensity during handball matches.From the web-based body temperature monitoring data, daily changes in the body temperature of all athletes and staff members were graphed. The results of the self-reported online questionnaire regarding the impression and general impact of the current PCR testing were visualized as a five-point Likert scale.For the social distancing AI monitoring data, the total sum of the proximity points for all proximity ID pairs was normalized by the number of associated athletes and defined as the cumulative proximity score. The cumulative proximity score was normalized by two separate unit time (UT) scales to consider the effect of respiratory rate (RR) on physical activity, since the risk of virus spread is theoretically proportional to RR, which is increased by physical activity ,19. The Based on the R–R interval of the ECG signal recorded with the wearable sensor device, the HR data (bpm) for the 3000 m high-intensity endurance test and the eight training matches were calculated. The maximum HR value for each athlete observed during the 3000 m run test was used to normalize the HR value during handball matches. The 3D acceleration data were used to determine the effective playing time. The norm of the 3D acceleration signal o et al. , which eAll numerical processing was performed with Matlab R2020a and R v4.0.2. Data analyzed in this manuscript will be made available from the corresponding author upon reasonable request.Demographic information on the participants is detailed in The reporting rate of the web-based monitoring was 88.7% throughout the survey period (10 November to 22 December) and 96.6% during the camp (24 November to 8 December). Every athlete completed their web-based monitoring.SARS-CoV-2 PCR testing history and results are summarized in A summary overview of the temperature checks documented by the participants is graphed in Results from the online questionnaire about infection test protocol were obtained from 27 athletes and 10 staff  Q1–Q7. OWe found that many athletes concentrated in a specific place during stretching time before practice . After providing feedback on this issue to the team on 27 November (day 5), the location of the athletes during stretching became dispersed, and the proximity condition was clearly reduced thereafter  on the third day of the training camp . With thIt is important to mention that the responsibility of data entry rested solely on the athletes. It is possible that athletes were anxious of missing out on competitive opportunities, making them occasionally hesitant to disclose their health status. While it was commendable that one athlete reported her fever, it was important to build a sense of safety among other athletes as well. We surmised that crucial appraisal regarding infection control by the JHA and frequent negative PCR testing promoted a positive mental outlook that would have led athletes to genuinely report their true health condition  Q5, Q6. Though we had no SARS-CoV-2-positive athletes during the entire duration of the camp, our frequent testing schedule (every 48 h or 72 h) enabled us to detect COVID-19-infectious athletes early, thereby minimizing the risk of virus spread. Larremore et al. suggested that repeated screening of susceptible but asymptomatic individuals could be used to limit transmission, and that the effectivity of screening therefore rests on accessibility, frequency, and sample-to-answer time . The accThe results of the online PCR survey highlighted the increased compliance of the athletes despite the high frequency of testing . While tReal-time quantitative monitoring using AI demonstrated the characteristics of the proximity status that occurred during on-court handball training. The quantitative visualization by the AI system showed that off-game situations such as stretching are more likely to result in significant proximity than in-game handball situations, and that these proximities can be alleviated by behavioral changes of athletes. In this way, the AI system was able to provide objective numerical scores to improve athlete behavior.If the stretching time could be construed as a “control” environment, the in-game matches served as a “test” condition to compare the proximity status between the players. A continuous-time density plot revealed that the proximities during a handball match were not as long-lasting as it was during stretching . The cumSince the primary aim of the training camp was to increase athlete performance, it was essential to quantify whether the physical intensity was demanding enough to fulfill this objective. Kniubaite et al.  reportedIt is important to note that the sample size for our study was low (29 athletes and about 10 staff per test day). Although our presented methodologies could be optimum for small sample sizes, for large-scale screening (>1000 samples) in the future, individuals organizing the team should consider an optimal screening strategy in terms of cost, technician availability, testing facilities, and warranting test accuracy. As with any self-reported survey procedure, there is a possibility of self-reporting bias among the athletes . With riAiding athletes in disrupting physical inactivity and normalizing their training routines during the pandemic was our central purpose, which led to the rebooting of high-performance sporting activities under the JS–CPS  and by the SRIP (Sports Research Innovation Project). The pursuit resulted in the successful management of a training schedule among handball players, providing a safe training environment for their handball practice within a stringent COVID-19 screening environment. Our efforts in this study are expected to set the foundation for future endeavors in standardizing training protocols and for scaling up to include for other team-based indoor sporting activities. Specifically, we believe that the short turnaround time for PCR testing is vital for the early identification and prioritization during the screening process. As an added benefit, the outcomes of this process also develop a sense of security among the athletes. Based on our results, an on-site, low-cost mass screening methodology will be beneficial to develop in the future. Using information technology, real-time quantification of health status and proximity metrics will be an indispensable tool to quantify the effect of risk management. These technological innovations developed under SRIP research can constitute a promising approach in building a safe environment to support athletic training during the pandemic.


Microbiota dysbiosis has been associated with chronic diseases ranging from gastrointestinal inflammatory and metabolic conditions to neurological changes affecting the gut-brain neural axis, mental health, and general well-being. However, current animal studies using oral gavage and gnotobiotic animals do not allow for non-invasive long-term access to gut microbiome. The purpose of the present study was to evaluate the feasibility of 3D-printed fistula implants through the body wall and into the cecum of rats to obtain long-term access to gut microbiome. Cecal fistulas were designed and 3D-printed using a high temperature resin . Nine male Sprague-Dawley rats underwent the fistula implantation. Food intake, body weight, and body fat were measured to determine the impact of fistula manipulation. Gut microbiome, vagal afferents in the hindbrain, and microglia activation were analyzed to determine if fistula implantation disrupted the gut-brain neural axis. We found that the procedure induced a transient decrease in microbial diversity in the gut that resolved within a few weeks. Fistula implantation had no impact on food intake, body weight, fat mass, or microglia activation. Our study shows that 3D-printed cecal fistula implantation is an effective procedure that allows long-term and minimally invasive access to gut microbiome. Firmicutes being the most abundant phylum, when compared to healthy subjects and patients with adenoma [The gut microbiome has become an area of intense study for contemporary researchers. Studies have shown that the gut microbiome plays a crucial role in early physiological development in humans, influencing everything from bone growth to the outcome of diseases such as asthma and certain neurodevelopmental disorders . Germ-fr adenoma .Escherichia coli and Bacteroides fragilis, among countless others, may have a more direct linkage to the onset and development of CRC than previously thought [Further, understanding the means by which dysbiosis can occur and be repaired is also important in capitalizing on its role as a potential biomarker for the onset of serious oncological conditions such as the aforementioned colorectal cancer (CRC). Current research shows that microbes such as  thought . These m thought . As such thought . Thus, mClostridioides difficile in current clinical settings, it continues to show promise in treating many diverse diseases with links to gut dysbiosis, such as inflammatory bowel diseases [With multiple studies showing the harmful effects of gut dysbiosis on a wide range of health endpoints, the question of how to efficiently restore gut health has moved to the forefront of gut microbiota research. One of the most prominent treatments currently being researched is the fecal transplant, wherein gut dysbiosis is treated with the introduction of “healthy” bacteria, often from the donor’s feces. Though this therapy is still limited primarily to the treatment of diseases ,10. It iMost studies involving microbiota transplant follow a standard experimental plan: subject animals are administered a powerful prophylactic antibiotic or are raised under GF conditions to prepare the animal for the transplant, before delivering the transplant through oral gavage, or, somewhat less commonly, with their food . The useAs previously mentioned, GF animals exhibit a host of developmental and behavioral abnormalities. It has also been noted that the ceca of germ-free rats could grow to up to five times larger than that of standard animals. These same authors note that the enlarged cecum also often suffers from fluid buildup leading to thinned cecal walls . Thus, uDue to the cost and difficulty in acquiring and maintaining germ-free laboratory animals, treating the subject animals with prophylactic antibiotics has become a popular method for “preparing” the subject for transplant. However, the reality is that the efficacy of prophylactic antibiotics for this purpose is questionable; with outcomes including that transplant following antibiotic intake shows no uptake of donor microbiota by the recipients compared to the untreated recipients . It has Transplant options following the preparation of the subject animal are similarly inefficient and rely almost entirely on oral gavage. Though select studies have detailed methods for preparing rodent chow containing donor microbiota, this methodology is labor intensive and would be a poor choice for large scale studies or those requiring specialized and standardized diets . The greThus, there is a meaningful need to explore alternate methods of microbiome manipulation and long-term and minimally invasive access to the gut microbiome. However, the studies revealing the methods for direct gut microbiome access in animal models are limited and do not provide information about long-term impact of the procedure on gut dysbiosis ,22. Thern = 12; ~300 g; Envigo, Indianapolis, IN, USA) were housed individually in conventional polycarbonate shoe-box cages in a temperature-controlled vivarium with ad libitum access to regular chow pellets  and water. Rats were maintained on a 12:12-h light: dark cycle with lights on at 0700-h and allowed to acclimate to laboratory conditions for one week prior to starting experiments. All animal procedures were approved by the University of Georgia Institutional Animal Care and Use Committee and conformed to National Institutes of Health Guidelines for the Care and Use of Laboratory. Male Sprague–Dawley rats (n = 3), Chow/C (n = 3), and Chow/F (n = 3). The HFD/F group was switched to a high-fat/high sugar diet. The other two groups remained on regular chow. During the last four weeks of the experiment, the HFD/F and Chow/F groups were restrained using a plastic decapicone three times per week, their fistulas were opened, and gut contents were removed using a 3 mL plastic pipette.The experiment had a duration of 12 weeks. During the first week, baseline measures of food intake, body weight, and body composition were taken. Then, the animals underwent the fistula implantation surgery and were allowed to recover for three weeks (weeks 2–4). After recovery, the animals were randomly assigned to following groups: HFD/F . n = 3), Chow/F , and HFD/F . Both the Chow/C and Chow/F groups remained on standard pellets of rat chow, and the HFD/F cohort was switched to a 45% fat, 20% sucrose diet . Rats were maintained on their respective diets for seven weeks. During the last three weeks on their respective diet, the Chow/F and HFD/F groups had their fistulas opened and closed three times a week to gauge the animals’ behavioral response to the manipulation and inspect the area.Following their recovery from surgery, animals were randomly divided into three experimental groups: Chow/C  was used to close the fistula opening.All fistulas were designed in Shapr3D and printed on a Formlabs Form 3, 3D printer using Formlabs High Temp Resin  . The fisFollowing the acclimation period, the animals underwent fistula implantation surgery . On surgA second, 15 mm vertical incision was made 20 mm to the right of the first abdominal incision and stretched with a pair of forceps to accommodate the fistula E,F. The During the postoperative period, the rats were monitored daily for the progression of their recovery. They received injections of buprenorphine (0.05–0.1 mg/kg IM) every 12 h to minimize post-surgery pain and gentamicin (0.1 mg/kg IM) to prevent infections. Animals were closely monitored and considered as fully recovered when body weight returned to pre-surgery body weight. Three of the 12 rats in this initial proof-of-concept trial did not have a full recovery and were removed from the experiment. See Fecal samples were collected at baseline (A), after recovery from surgery (B), four weeks after the introduction of the high energy density diet (C), and on the last day of the experiment (D). Bacterial DNA was extracted from feces using a commercial kit . High throughput sequencing was performed using Illumina MiSeq paired-end runs . Amplification targeted the V3-V4 region of the 16S ribosomal RNA genes using the following primers: S-D-Bact-041-b-S-17 (5′-CCTACGGGNGGCWGCAG-3′) forward and S-D-Bact-0785-a-A-21 (5′-GACTACHVGGGTATCTAATCC-3′) . 2 and transcranial perfused with 0.1 M phosphate-buffered saline  followed by 4% paraformaldehyde. Hindbrains were harvested, post-fixed in 4% paraformaldehyde for 2-h, and immersed in 30% sucrose, 0.1% NaN3  in PBS and stored at 4 °C until processing. Hindbrain samples were cryosectioned  at 20 μm thickness.Rats were anesthetized with COStandard immunofluorescence was used to determine microglia activation and vagal afferent density in the hindbrain. Sections were incubated overnight with a primary antibody against ionized calcium-binding adaptor molecule 1  followed by Alexa-488 secondary antibody to visualize microglia activation as previously described ,23.GraphPad Prism 7  was used to conduct statistical analyses. Data are expressed as mean ± SEM and were analyzed using ANOVA followed by Holm-Sidak multiple comparisons test. The alpha value for statistical significance was set at 0.05.Multiple collections of the cecal content via 3D-printed High Temp Resin cecal fistula over a period of four weeks (p < 0.05) in the high-fat fed animals  showed no significant difference in the density of the vagal afferents among the groups . SimilarThe goal of this study was to evaluate the feasibility of a 3D-printed fistula designed in our laboratory as a method for obtaining direct access to gut microbiome without inducing long-term dysbiosis following the implantation of the fistula in the cecum of rats. Results of the study show that implanting a cecal fistula did not induce long-term dysbiosis and did not affect the integrity of vagal gut-brain connections. Moreover, cecal fistula manipulation did not impact food intake, body weight, or fat mass. These results indicate the implantation of a cecal fistula is an effective procedure that allows long-term and minimally invasive access to the gut microbiome to better facilitate future studies on microbiome transplants by minimizing the limitations of currently used methods in the field of microbiome research. The surgical implantation procedure proved to be well tolerated among study animals with no alteration in their mobility or physical activity, indicating the long-term efficacy of the device. By the endpoint of the experiment, all animals were found to be in good health. Fistula manipulation during the cecal content (gut microbiome) sampling also did not induce changes in food intake, body weight, accumulation of fat mass, or rat behavior. Previous studies revealed that oral gavage, the most common method to manipulate gut microbiome, can induce significant stress to laboratory animals ,24 and cThe most noteworthy finding of the present study was that implanting a cecal fistula did not induce long-term dysbiosis. While the majority of currently reported experiments involving microbiota transplant use animals prepared for the transplant by administration of powerful prophylactic antibiotics, the use of prophylactic antibiotics is a significant limitation in the current fecal transplant methodology . Due to And finally, the results of our study revealed that cecal fistula implantation numerically increased microglia activation and decreased the density of vagal afferents in the hindbrains of Chow/F and HFD/F rats, but the observed changes did not reach statistical significance. An increase in microglia activation and decrease of vagal projections to the hindbrain observed in the HFD/F group (rats fed a high-fat diet) was similar to previously reported observations ,28. TherWhile the results of the study showed improvements over currently used methods of gut microbiome manipulations, this pilot investigation also identified several potential improvements in the fistula design. Future iterations will be printed with a shortened middle section as well as a reduced diameter for the inner flanges. While the current design is functional but not fully optimized for the direct access of cecal content, it is believed that these improvements will greatly reduce the likelihood of any post-surgery complications as the rodents adapt to the implantation of the device. The 3D-printed nature of the fistula means that such improvements can be swiftly implemented and produced for future studies at little cost. Additionally, though the aforementioned high temperature resin provided an adequate research tool, advancements in 3D printing technology may make the production of titanium devices financially viable in the near future, increasing the reusability and, thus, the efficacy of the device as a research tool. The results of our study show that the implantation of a 3D-printed cecal fistula, using a high temperature resin, is an effective procedure that allows long-term and minimally invasive access to the gut microbiome. They expand the knowledge on previously published cecal fistulation methods ,22 by prWhile our results advance the knowledge on cecum fistulation and enable low-stress and long-term access to gut microbiome, there are two major limitations in this study that will be addressed in future research. First, using more animals in each group could introduce the statistical significance in microglia activation changes observed after the fistula implantation, suggesting that the procedure is altering vagal gut-brain signaling. And second, the microbiome analysis from cecal content samples, collected during the study, could directly address the influence of oxygen entering the cecum on intestinal flora and fermentation. Therefore, we plan to address the above limitations in future studies. In conclusion, our results demonstrate that 3D-printed cecal fistula implantation is an effective procedure that allows long-term and minimally invasive access to the gut microbiome in rats without the confounding negative side effects observed with other methods currently in use. Moreover, the manipulation of gut microbiome via cecal fistula could enable potential treatments for a wide array of diseases. Studies are now needed to explore this method further, in order to better understand the mechanisms by which researchers can influence the development or treatment of disease through the manipulation of the gut microbiome.


Several cutaneous manifestations following COVID-19 vaccination have been cited in the literature since the beginning of the pandemic. Two case reports regarding the development of vitiligo after receiving the COVID-19 vaccine. Herein, we present a case report of a patient who developed new-onset vitiligo two weeks after receiving her COVID-19 vaccine. Although the pathogenesis is unclear, it may be related to the inflammatory cells involved in both the pathogenesis of vitiligo and the mechanism by which the COVID-19 vaccine stimulates the immune system. This case report highlights the need for further investigation into the link between COVID-19 and the development of vitiligo. Since the start of the coronavirus COVID-19) pandemic, there have been several cutaneous manifestations in COVID-19 vaccinated patients cited in the literature. Most commonly are injection site reactions, as well as localized facial swelling in areas where previous dermal fillers have been placed [9 pandemiA 67-year-old woman with no significant past medical history presented to the dermatology clinic for an evaluation of a new onset of skin discoloration of the bilateral hands which had been present for several months. The patient reported that the discoloration began two weeks after receiving the COVID-19 Moderna vaccine. Physical examination revealed multiple depigmented patches primarily located on the bilateral dorsal hands (Figure Although our patient's vitiligo may have developed idiopathically, the temporal association of her presentation after the vaccine combined with the absence of other risk factors makes it probable that her vitiligo was likely secondary to her COVID-19 vaccination. There have been two previous case reports that have also indicated a temporal association between the COVID-19 vaccine and the development of new-onset vitiligo; one occurring in a 58-year-old man with a prior history of ulcerative colitis following the Pfizer vaccine and another occurring in a 61-year-old woman following the Moderna vaccine ,3.The pathophysiology leading to vitiligo in the setting of COVID-19 vaccination remains unclear but there are several hypotheses. Most notably, there may be a link between the inflammatory cells involved in each pathway. Immune mechanisms such as antigen presentation, cytokine production, epitope spreading, and polyclonal activation of B cells are involved in both the anti-infectious immune response as well as in autoreactivity . In the COVID-19 is still a relatively new disease and the vaccine has only been available since December 2020; therefore, little is known regarding the possibility of triggering an autoimmune disease post-vaccination. However, there have been other reports of patients developing autoimmune conditions, such as immune thrombocytopenic purpura after receiving the vaccine .Given that the COVID-19 vaccination has the potential to cause an extensive inflammatory response, it would be unsurprising if more cases of autoimmunity begin to emerge. Our understanding of autoimmune reactions following COVID-19 vaccination continues to expand, and this case emphasizes that COVID-19 vaccination may be among the list of triggers for vitiligo. This case report along with the two other case reports highlights the need for future studies to further investigate this link.


Three-dimensional (3D) reconstruction in single-particle cryo-electron microscopy (cryo-EM) is a significant technique for recovering the 3D structure of proteins or other biological macromolecules from their two-dimensional (2D) noisy projection images taken from unknown random directions. Class averaging in single-particle cryo-EM is an important procedure for producing high-quality initial 3D structures, where image alignment is a fundamental step. In this paper, an efficient image alignment algorithm using 2D interpolation in the frequency domain of images is proposed to improve the estimation accuracy of alignment parameters of rotation angles and translational shifts between the two projection images, which can obtain subpixel and subangle accuracy. The proposed algorithm firstly uses the Fourier transform of two projection images to calculate a discrete cross-correlation matrix and then performs the 2D interpolation around the maximum value in the cross-correlation matrix. The alignment parameters are directly determined according to the position of the maximum value in the cross-correlation matrix after interpolation. Furthermore, the proposed image alignment algorithm and a spectral clustering algorithm are used to compute class averages for single-particle 3D reconstruction. The proposed image alignment algorithm is firstly tested on a Lena image and two cryo-EM datasets. Results show that the proposed image alignment algorithm can estimate the alignment parameters accurately and efficiently. The proposed method is also used to reconstruct preliminary 3D structures from a simulated cryo-EM dataset and a real cryo-EM dataset and to compare them with RELION. Experimental results show that the proposed method can obtain more high-quality class averages than RELION and can obtain higher reconstruction resolution than RELION even without iteration. Cryo-electron microscopy (cryo-EM) has become a recognized powerful technique in structural biology for three-dimensional 3D) structure determination of biological macromolecules, supramolecular complexes, and subcellular structures ,2,3. It D structuAs one of the major cryo-EM techniques, single-particle reconstruction has become one of the most successful techniques for structural biology ,12,13. SClass averaging in single-particle cryo-EM is an important procedure for producing high-quality initial 3D structures and discarding invalid particles or contaminants . It orgaDifferent solutions have been proposed for solving the 2D class averaging problem in cryo-EM ,29,30,31Image alignment is a fundamental step in the class averaging procedure ,38. The 2D interpolation in the frequency domain is used to improve the estimation accuracy of the alignment parameters, which can obtain subpixel and subangle accuracy.The alignment parameters of rotation angles and translational shifts in the x-axis and y-axis directions can be computed directly in Fourier space without enumeration, which is very fast.A spectral clustering algorithm is used for the unsupervised 2D classification of single-particle cryo-EM projection images.Image alignment is aimed at estimating three alignment parameters: a rotation angle and two translational shifts in the x-axis and y-axis directions. Image rotational alignment and translational alignment in real space need too many iterations to compute the alignment parameters, and the calculated alignment parameters are integers. In Fourier space, alignment parameters can be computed directly without enumeration. In this paper, an efficient image alignment algorithm using the 2D interpolation in the frequency domain of images is proposed to improve the estimation accuracy of alignment parameters, which can obtain subpixel and subangle accuracy. Specifically: (1) for image rotational alignment, two images are transformed by polar fast Fourier transform (PFFT) to calculate a discrete cross-correlation matrix, and then the 2D interpolation is performed around the maximum value in the cross-correlation matrix. The rotation angle between the two images is directly determined according to the position of the maximum value in the cross-correlation matrix after interpolation. (2) For image translational alignment, all operation steps are consistent with image rotational alignment, where fast Fourier transform (FFT) is used instead of PFFT. (3) For image alignment with rotation and translation, only a few iterations of combined rotational and translational alignment are needed to align images. Furthermore, the proposed algorithm and a spectral clustering algorithm  are usedThe rest of this paper is organized as follows: In In this section, the proposed image alignment algorithm is demonstrated in detail, including (1) image rotational alignment; (2) image translational alignment; and (3) image alignment with rotation and translation. The diagrams of the proposed image rotational and translational alignment algorithms using 2D interpolation in the frequency domain of images are shown in p, image rotational alignment in real space requires Image rotational alignment is one of the basic operations in image processing. The rotation angle between two images can be estimated either in real space or in Fourier space. In real space, image rotational alignment is a rotation-matching process, that is, an exhaustive search. An image is rotated in a certain step size, and the similarity between the rotated image and the reference image is calculated. When the image is rotated for one circle, the index corresponding to the maximum similarity is the final estimated rotation angle between the two images. This method is simple, but it is time consuming and inaccurate. Assuming the search step size is C is calculated according to:C need to be circularly shifted by C, where the function C is Step 1: Calculate a cross-correlation matrix using PFFT. Firstly, images C. The rotation angle C on the x-axis. The rotation angle calculated by this method is an integer. In order to calculate the rotation angle more accurately, the 2D interpolation is performed around the maximum value in the cross-correlation matrix C. Specifically, an 11 * 11 matrix C is extracted from the matrix C . The preliminary 3D structure was reconstructed from the generated class averages using the common-lines-based angular reconstruction method [The proposed image alignment algorithm and the normalized spectral clustering algorithm  with adjn method , which wn method , where tn method . All cryn method ,54.Firstly, 10,000 clean centered EMD5787 projection images with the size of Then, the cryo-EM projection images were aligned using the image alignment algorithms IAFI and IAF. The similarity matrix between the aligned projection images was converted into an adjacency matrix using the kNN and SNN algorithms, which was input into the normalized spectral clustering algorithm for 2D classification. The 10,000 aligned projection images were classified into 100 classes. The projections classified into the same class were aligned and weighted averaged to produce a class average. Finally, the preliminary 3D structure was reconstructed from the selected good class averages. The class averaging technique is useful for the 2D analysis of electron micrographs as well as in single-particle cryo-EM 3D reconstruction. Image alignment is a fundamental step in the class averaging procedure. In this paper, an efficient image alignment algorithm using the 2D interpolation in the frequency domain is proposed. The proposed image alignment algorithm was tested on a Lena image and two datasets of cryo-EM projection images for estimating alignment parameters. The simulation results show that the image alignment algorithm in Fourier space using the 2D interpolation can achieve higher estimation accuracy for alignment parameters than the image alignment algorithm in Fourier space without interpolation. It is also found that image alignment in Fourier space is faster than that in real space. In addition, the proposed image alignment algorithm and the normalized spectral clustering algorithm were used to produce class averages for reconstructing preliminary 3D structures. Results on datasets of simulated and real cryo-EM projection images indicate that the proposed method can be used to improve the resolution of the reconstructed preliminary structure. The main drawback of this study is that the contrast transfer function (CTF) parameters were not considered during the class averaging, which may limit the potential benefits of using the proposed method. In future work, we will integrate the CTF parameters into the class averaging procedure and apply the proposed method to large-scale datasets of cryo-EM projection images for high-resolution cryo-EM 3D reconstruction.


Computed Tomography has become a vital screening method for the detection of coronavirus 2019 (COVID-19). With the high mortality rate and overload for domain experts, radiologists, and clinicians, there is a need for the application of a computerized diagnostic technique. To this effect, we have taken into consideration improving the performance of COVID-19 identification by tackling the issue of low quality and resolution of computed tomography images by introducing our method. We have reported about a technique named the modified enhanced super resolution generative adversarial network for a better high resolution of computed tomography images. Furthermore, in contrast to the fashion of increasing network depth and complexity to beef up imaging performance, we incorporated a Siamese capsule network that extracts distinct features for COVID-19 identification.The qualitative and quantitative results establish that the proposed model is effective, accurate, and robust for COVID-19 screening. We demonstrate the proposed model for COVID-19 identification on a publicly available dataset COVID-CT, which contains 349 COVID-19 and 463 non-COVID-19 computed tomography images. The proposed method achieves an accuracy of 97.92%, sensitivity of 98.85%, specificity of 97.21%, AUC of 98.03%, precision of 98.44%, and F1 score of 97.52%. Our approach obtained state-of-the-art performance, according to experimental results, which is helpful for COVID-19 screening. This new conceptual framework is proposed to play an influential task in the issue facing COVID-19 and related ailments, with the availability of few datasets. Coronavirus disease 2019 (COVID-19) has become a pulmonary ailment instigated by severe pneumonia diseases. Wuhan city of Hubei province in China is the ground-zero of the epidemic where COVID-19 was first discovered in December 2019, and has since escalated around the world, resulting in the ongoing coronavirus pandemic of 2021. As of 3 January 2022, there has been over 290 million confirmed cases and over 5.4 million deaths globally  have beeSeveral studies have presented different methodologies using artificial intelligence to diagnose COVID-19. Some utilized CXR images while others applied CT images. In this section, we present relevant studies on both CXR and CT images sequentially. Given enough data, CNNs have achieved many accomplishments in a diverse area of medical diagnostic imaging . This deRecent studies have focused on an automatic diagnostic procedure of COVID-19 pneumonia from CT scans, with positive results ,15,16,17Another paper proposed the COVID-Net, which is a CNN-based model for the detection of COVID-19 cases using CXR images. Using the COVIDx dataset, an accuracy of 93.3% and sensitivity of 91.0% were actualized. A Pre-trained ResNet50 CNN with ImageNet weight adequately identified COVID-19 with 94% accuracy using private CT datasets in . For pulA segmented CT scan in  was propDeep Learning architecture was suggested in  to adequSingh et al.  proposedAdversarial learning , a technThis work’s contribution is as follows: (1) To the best of our knowledge, this is the first study to combine modified enhanced super-resolution GAN with a Siamese capsule network for COVID-19 diagnosis. The modified enhanced super-resolution generative adversarial network used in this study generates super-resolution CT images (SR) from low-resolution CT images of which distinct information can be extracted. The MESRGAN addresses the problem of low quality images and helps to remove noisy artifacts generated by GAN due to the decompressing nature of JPG format images. (2) To reduce the computational overheads and avoid framework, we incorporated a Siamese capsule network. The super-resolution CT images achieved from the MESRGAN+ are directly sent to the Siamese capsule network for identification of COVID-19 in an end to end fashion, resulting in improved screening accuracy.The following is how the rest of the paper is organized: The approach is explained in detail in This section presents the problem statement, dataset, and preprocessing procedure used in this study. Next, we explained the Siamese capsule network and modified enhanced super-resolution GAN plus based on low quality images for COVID-19 identification (MESRGAN+ Siamese-CapsNet). Lastly, we provided the implementation details for our proposed model.Effective COVID-19 screening is needed in light of the looming pandemic threat. The lack of COVID-19 test kits in many developed or rural areas, as well as the time taken to produce the samples (proper) results, poses a significant problem for developing countries with under-equipped hospitals and clinics. Developing countries frequently lack sufficient COVID-19 kits, limiting primary healthcare clinics’ ability to receive, ship, and analyze, forcing them to rely more on specialized centers in providing them with the test results. To react to the third wave of the pandemic in areas with low access to viral or antibody tests, which can be useful in COVID-19, plays a major role, an automated and efficient method is required to meet the increasing demand for new test cases. Many studies have shown that CT scans can detect ground–glass opacities and other chest features that are higher in resolution than those of a normal CXR . Neverth(1) The low resolution (LR) features is a problem.(2) The collected dataset samples are often limited and may include fuzzy and meaningless data.Additionally, experienced radiologists have difficulty distinguishing between the symptoms of COVID-19 pneumonia and community-acquired bacterial pneumonia while examining CT images . FurtherIn this study, we used an open-source dataset called a COVID-CT dataset. The dataset was obtained from Yang et al.  and consIn this study, our proposed model is subdivided into three stages. Firstly, the CT images of arbitrary resolution are passed to the image scaling-adaptive module for resize. Secondly, the super-resolution architecture, called the Modified Enhanced Super Resolution GAN (MESRGAN+), is used to recreate LR images into high-resolution and eliminate compression artifacts. Finally, the reconstructed HR image is passed to the Siamese capsule network to extract and learn discriminative features for the screening of COVID-19.During the training phase, the OpenCV image scaling method adjusted the different resolutions to a fixed resolution of In this study, our aim is to enhance the low quality CT images into a super-resolution before passing through the Siamese capsule network for COVID-19 identification. We will present the proposed modified enhanced super resolution generative adversarial network plus (MESRGAN+) architecture and its structural improvement for achieving a balance in perceptual quality and PSNR in this section. Hence, we will briefly highlight the transition of SRGAN to MESRGAN+.SRGAN  utilizesIn our proposed super resolution architecture, the overall structural configuration of the Residual-in-Residual Dense Block (RRDB) in ESRGAN+ is kept the same as shown in To produce the high-resolution images from the scale-adaptive module, the scale factor is increased to 4. This image’s network generator produces As Equation  is evalujth-convolution and before the max-pooling layer. The formality is measured as the distance between the function representations of the super-resolution image Perceptual loss works to improve the texture and picture accuracy of the generated images . Euclideition of , the feaEquation :(2)ΠPercInstead of penalizing the output image vBy manipulating the HR image Equation  calculatThe majority of the preliminary research focused on standard GAN. Meanwhile, we employ a rational discriminative loss in our SR network, ensuring that HR photos are not stylized or unrealistic. In Equations  and 5),,5), the Equations  and 5)  5) reflestic GAN  to distiRGAN produces images with sharp edges when used in a relativistic model and provides more graphic and detail information than a typical GAN. It is seen in Equations  and 7)  7) that Equation  analyzesEquation  analyzesEquation  defined Despite this, Equation  illustraThe network is concurrently trained for both actual image Traditional CNN has achieved tremendous results in feature extraction of target images. Furthermore, the primary aim of the pooling layer is to achieve dimensionality reduction, but it could also lead to loss in spatial details, large rotation, and directional movement of the target images. This is one of the reasons for CNN’s unsatisfactory classification performance. To this effect, we proposed a Siamese capsule network sharing the same weights and parameters to effectively identify COVID-19. For classification problems, the authors in  were thej, j; the indicator that depicts the degree of which capsule i activates capsule j is called the coupling coefficient i to capsule j is illustrated below in Equation  and Siamese convolutional capsule network (CapsNet) as seen in Equation :(11)Cj=∑Equation :(12)Uj/ii and j. A robust routing method [i and other linked capsules in the above layer summing to 1. To ignite another capsule, the robust routing method, known as routing by agreement, considers both the length of a capsule and its instantiation parameters. This differs from traditional CNN models, which simply evaluate probability. As a result, capsule networks are reliable and more powerful at abstracting inherent object characteristics. Recall that the capsule’s length is used to determine the likelihood of an entity’s presence. A nonlinear “squashing” function is used as the activation function for the convolutional capsule layers in ensuring a perfect probability estimation where capsules with short vectors have low probability— otherwise, high probability all at maintaining a constant orientation. Squashing function is given in Equation (g method  decides Equation  as:(13)UThe max-pooling layer in the capsule performs feature down-sampling in order to reduce the network size. However, we adopted DWT pooling of In this study, we adopted a VGG16 pre-trained network as the backbone feature extractor in our proposed Siamese capsule network. We fine-tuned the network by replacing the max-pooling layers in each convolutional block with discrete wavelet transform (DWT) pooling except for the first convolutional block, which retains its max-pooling layer. Furthermore, the max-pooling layer in the last convolutional block is completely eliminated without a replacement in order to arrive at a feature tensor of D is the Euclidean distance between two similar or dissimilar images, and W represents the mutual parameter vector in neural networks. Y indicates whether the two images We added a dropout of 0.5 before the PrimaryCaps to avoid over-fitting. The PrimaryCaps consists of a 6D convolutional capsule layer of 32 channels and each PrimaryCaps consists of six convolutional units. In total, the PrimaryCaps has a dimension of Equation  expresseThe COVID-19 identification network is constructed using super-resolution HR imagery. We trained this network on the NVIDIA GTX1080. Keras is used for the construction of the COVID-19 scheme. To construct our batch, we paired a single image with ten separate images. If the images were the same, we labeled the pair as 1, else, we labeled it 0. This pairing process was repeated for a total of 400 images and thus amounted to 4000 training pairs. This is one of the significant advantages of the siamese neural network. We can generate a large number of training pairs using a relatively smaller number of training images. In this work, we adopted a pre-trained VGG 16 model as the backbone for the siamese capsule network as seen in In investigating the performance of our proposed architecture on COVID-19 screening diagnosis, we sorted for an open domain dataset of CT images called the COVID-CT dataset. The authors in  obtainedThis comprises of two parts—first, to illustrate the super-resolution network’s benefits in the image generation process. The second phase reports the performance metric of the proposed method. The evaluation criterion adopted as the metric to examine the diagnostic performance of our COVID-19 identification framework is as follows: accuracy (ACC), sensitivity (SEN), specificity (SPE), precision (PREC), F1-score, and the area under curve (AUC) represented from Equations –20):(16:(1620): CapsNet without max-pooling (replaced with DWT pooling): In this network, the max-pooling layers in VGG16 which serve as the feature extractor were totally replaced with DWT pooling, except for the first convolutional block in order to save the location information of the features.(2) CapsNet with max-pooling: In contrast to the above network, the max-pooling layers were kept the same without making any changes to the VGG16 pre-training architecture.The experimental results are summarized in In addition, we examined the effect of regularization to network robustness by conducting another set of experiments on our proposed MESRGAN+ Siamese-CapsNet. Particularly, we made comparison on the following two architectures:(1) MESRGAN+ Siamese-CapsNet without regularization: In this model, we remove the regularization.(2) MESRGAN+ Siamese-CapsNet with regularization: Contrary to the model above, we keep the regularization.The experimental results are summarized in In this section, we adopted ROC and precision–recall curves as the evaluation criteria to examine how well our model performs in comparison with a famous CNN model such as AlexNet, VGG16, and ResNet50. We compared the outcomes of our proposed algorithm with published State of the art (SOTA) COVID-19 screening methods which are as follows: Song et al. , Tang etCOVID-19 has become a serious threat to health, and numerous solutions have been gathered together in combating it globally. Meanwhile, there are limited COVID-19 images in CT as compared to healthy images or other pneumonia—in as much as there is difficulty for humans to accurately differentiate COVID-19 CT images from other diseases or healthy images. The low-resolution and distortion of CT images have also contributed to the factors affecting the accuracy of detecting COVID-19 from other pneumonia. Therefore, we have presented an AI-based method for diagnosing COVID-19, which is an integration of modified enhanced super-resolution generative adversarial network plus (MESRGAN+) and the Siamese capsule network. First, the purpose of the modified enhanced super-resolution GAN plus is to achieve a higher-resolution from a low-resolution counterpart of the CT images. The HR output from MESRGAN+ module is fed into the Siamese capsule network in an end-to-end framework to learn the distinctive features for the identification of COVID-19.Our proposed identification network is a lightweight Siamese capsule network with VGG16 pre-trained network as the backbone with shared parameters and weights for COVID-19 screening. The identification network determines the verification and identification loss simultaneously on the premise of a pair of CT training images. The network learns discriminative features and estimates the similarity score to determine whether the pair of input CT images includes the same scans or not. Additionally, a lot of papers have reported the possible causes of gradient-related bottlenecks and high computational cost due to architectural complexity. This paper utilizes a simple dual network of convolutional capsule network constructed using a VGG16 pre-trained model to extract high-level features which are fed to the primary capsule containing several convolutional capsule layers and finally connected to the fully connected layers used for aggregating the features extracted. L2 normalization term is utilized to normalize the CNN embeddings from which the contrastive loss function and Euclidean distances metric are used to estimate the distances and similarity scores between two CT scans.It is well considered that the decline in performance of image-based COVID-19 diagnosis is because of the low quality dataset of CT. However, this argument is one-sided because it is evident that a deeper convolutional network suffers some setbacks such as exploding and vanishing problems. Therefore, we conclude that data quality and architectural complexity are equally responsible for the poor performance in the AI-based COVID-19 image screening task. To overcome these bottlenecks, we combined the modified enhanced super-resolution generative adversarial network plus (MESRGAN+) and the Siamese capsule network in an end-to-end framework for COVID-19 diagnosis. Based on the well-known evaluation metrics, the proposed COVID-19 identification network outperforms SOTA methods as illustrated in In our paper, we proposed a joint framework of a modified enhanced super-resolution generative adversarial network plus (MESRGAN+) and the Siamese capsule network in an end-to-end framework for COVID-19 identification. First, the purpose of the modified enhanced super-resolution GAN plus is to achieve a higher-resolution from a low-resolution counterpart of the CT images. The HR output from MESRGAN+ module is fed into the Siamese capsule network in an end-to-end framework to learn the distinctive features for the identification of COVID-19. Furthermore, we explore the advantage of a capsule network and discrete wavelet transform pooling for obtaining spatial details of features and learn the distinctive features to deal with the discriminative problems of radiograph images by introducing Siamese learning technique in order to solve the problem of an insufficient CT dataset. In order to enhance the network robustness, we introduce a regularization term. From the experimental results, our proposed model is effective and converges very fast with better classification performance. In the future, we will focus on implementing one-shot learning in our model. To our knowledge, this is the first study to combine modified enhanced super resolution GAN plus with a Siamese capsule network as a cooperative learning method for a COVID-19 identification task from CT scans. We have demonstrated that our model can create more reasonable and real images, as well as capture deep features for COVID-19 identification. With a wide margin, our proposed approach outshone some of the SOTA COVID-19 screening techniques achieving an accuracy of 97.92%, sensitivity of 98.85%, specificity of 97.21%, AUC of 98.03%, precision of 98.44%, and F1 score of 97.52%, which is helpful for COVID-19 screening.There are some drawbacks to this study; firstly, the perceptually compelling reconstruction of images is a difficult task that will be addressed in the future. The construction of content loss functions that characterize picture spatial content but are less sensitive to changes in pixel space may further enhance realistic image SR outcomes. Secondly, COVID-19 symptoms may resemble those of other pneumonia such as viral pneumonia, bacterial pneumonia, and so on. We solely compared CT exams of COVID-19 infection to that of healthy CT. The patient’s contact history, travel history, early symptoms, and laboratory evaluation are still required for a COVID-19 clinical diagnosis. Thirdly, the number of model samples in this investigation was limited. To improve accuracy in the future, the quantity of training and test samples should be increased. To deal with the complex clinical condition, more multi-center clinical trials should be done.


She stabilised after preoperative neoadjuvant chemotherapy, surgery, and postoperative adjuvant chemotherapy. In September 2019, positron emission tomography (PET)/CT re-examination suggested a peritoneal metastasis and multiple lymph node metastases. She then received six cycles of camrelizumab plus chemotherapy. PET/CT indicated that the metastatic foci had disappeared and that she had achieved a clinical complete response(CCR). She was followed-up with camrelizumab plus capecitabine (maintenance therapy). At the time of writing, her progression-free survival is more than 14 months and her quality of life is good. Thus, camrelizumab plus chemotherapy is a useful first-line treatment for HER2- and PD-L1-negative advanced gastric adenocarcinoma.We report a rare case of PDL1-negative advanced gastric adenocarcinoma that improved significantly after camrelizumab plus chemotherapy followed by camrelizumab plus capecitabine as first-line therapy. A 65-year-old woman was diagnosed with a gastric adenocarcinoma in 2017  Gastric cancer is the fifth most common cancer worldwide and the fourth leading cause of cancer-related death . PeritonSystemic chemotherapy is an effective first-line treatment for advanced gastric adenocarcinoma. Currently, two drug regimens featuring fluorouracil combined with platinum or taxanes are used in clinical practice. However, the effectiveness of chemotherapy alone is limited. In patients with advanced gastric adenocarcinomas, immunotherapy combined with chemotherapy affords stronger anti-tumor activity as first-line therapy than does chemotherapy alone , 6. In ovia chest and abdominal contrast-enhanced computed tomography (CT) and endoscopic biopsy in July 2017. After three courses of routine preoperative 5-fluorouracil/leucovorin, oxaliplatin, and docetaxel (FLOT) chemotherapy, she underwent radical gastrectomy. The final histopathology was that of a poorly differentiated adenocarcinoma with lymph node metastases (stage pT3N2)  Figure 1After the completion of six courses of adjuvant FLOT chemotherapy, the patient was followed-up for nearly 2 years with no evidence of recurrence. In September 2019, she developed right lower abdominal pain. Positron emission tomography (PET)/CT revealed metabolically active soft tissue foci in the right lower chest wall that were thought to be metastases, with local invasion of the adjacent peritoneum, and suspected involvement of the liver. Multiple patches and nodular soft tissue foci in membranes were also thought to be metastases. The patient strongly desired immunotherapy, even though her PDL-1 expression status was unclear. After camrelizumab plus CAPOX , PET/CT re-examination on May 6th, 2020, indicated the disappearance of all lesions in the right lower chest wall and the abdominal peritoneum. She thus exhibited a CCR. During the treatment, we tested the original stomach tumor again and the result was negative for PDL-1 Figure 1Systemic chemotherapy (fluoropyrimidine plus platinum) remains the principal first-line therapy for patients with unresectable advanced or metastatic gastric or gastroesophageal junction (G/GEJ) adenocarcinomas not expressing HER2 . HoweverThis is the first report of a CCR in a patient with an advanced gastric adenocarcinoma treated with camrelizumab plus chemotherapy followed by camrelizumab plus capecitabine first-line therapy. Her PD-L1 status remains unknown and her HER2 status is negative, she exhibited a significant response. Even if the patient is later found to be PD-L1-negative, her PFS has so far endured for more than 14 months. Treatment was (and is) well tolerated, she has evidenced only mild myelosuppression and immune system-related skin reactions. There are some reports of camrelizumab combined with lenvatinib . HoweverHowever, the study has shortcomings: Initially, patients with advanced gastric cancer can achieve a complete response of 1-4% with CAPOX or XELOX combination therapy, and the efficacy of the model of camrelizumab plus chemotherapy followed by camrelizumab plus capecitabine in advanced gastric cancer needs to be further verified through phase 2 and phase 3 clinical trials. Furthermore, the anti-tumor mechanism of camrelizumab combined with chemotherapy still needs further study. Finally, when the patient was found with chest wall metastasis, she did not consent to pathological biopsy. There was a lack of assessment of the possible tumor heterogeneity of the metastasis.The original contributions presented in the study are included in the article/supplementary material. Further inquiries can be directed to the corresponding author.Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.JL, JY, and YC contributed to conception and design of the study. WW and XL organized the database. JL and JY wrote the first draft of the manuscript. All authors contributed to manuscript revision, read, and approved the submitted version.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.