Effects of seasonal changes on T-helper 1/T-helper 2 immune balance and eczema onset in rats

Objective: To explore the impact of seasonal changes on the T-helper 1(Th1)/T-helper 2(Th2) immune balance of the body in order to elucidate the internal immunological mechanisms underlying seasonal eczema.Methods: Eighty 4-week-old male Sprague-Dawley rats were divided into 5 season groups kept in corresponding season simulation environments, and subdivided into the model group and the control group. The Eczema Area and Severity Index(EASI) and scratching frequency were evaluated. The serum levels of immunoglobulin E(IgE), interleukin-2(IL-2), interleukin-12(IL-12), and interferon-gamma(IFN-γ), interleukin-4(IL-4), interleukin-25(IL-25), and interleukin-31(IL-31), and melatonin(MT), as well as the MT receptor(MTR) levels in the spleen, were detected by enzyme-linked immunosorbent assay analysis. The mRNA expression levels of T-bet and GATA3 were detected by quantitative real-time polymerase chain reaction.Results: EASI scores and the scratching frequency of the model group were higher in the long summer than in the other 4 seasons. Meanwhile, the serum levels of IgE and the Th2 cytokines IL-4, IL-25, and IL-31, as well as GATA3 mRNA expression levels, were high during the long summer in both groups. However, the serum levels of the Th1 cytokines IL-2, IL-12, and IFN-γ, as well as MT, MTR, and T-bet mRNA levels, were lower during the long summer. In all 5 seasonal groups(spring, summer, long summer, autumn, and winter), the levels of all immune factors, especially IL-4 and IL-31, were higher in the model group than those in the control group,while the concentrations of MT and MTR were lower.Conclusion: Under long light, hot, and humid conditions in the long summer, the body is more likely to suffer from Th2-dominated immune imbalance. This is the internal mechanism behind the high incidence and severity of eczema during the long summer. MT and MTR play a key role in the seasonal onset of eczema.

MTT Detection of the Toxicity on CdTe Quantum Dots

Objective: The quantum dots are the useful materials in microelectronics and biomedical research. However its toxicity has to be considered. We studied the effect of cell inhibition with ZnS core quantum dots and CdTe quantum dots modified with Thioglycolic acid or Cysteine functional group (TGA-CdTe, TGA-CdTe/ZnS, Cys-CdTe, Cys-CdTe/ZnS) on Caco-2 cell proliferation. Methods: We studied the effect of cell inhibition with ZnS core QDs and CdTe QDs modified with functional group on Caco-2 cell proliferation by MTT assay at 0, 12.5, 25, 50, 100 μg/ml and 6, 24, 48 h. Result: Our results showed that all QDs have inhibited cell proliferation and reached maximum 79.21%. The inhibition rate of Cys-modified QDs increased with the increase of concentration and reached maximum 66.72%. The inhibition rate of TGA-modified QDs increased with the increase of time. The ratios of Cys-modified to TGA-modified were less than 1 at all concentrations and three exposure times (P ≤ 0.01). The average ratios of Cys-CdTe/ZnS to Cys-CdTe reached 1.11 only for 48 h (P ≤ 0.05). The ratios of TGA-CdTe/ZnS to TGA-CdTe were closed to 1 at all concentrations and exposure times. Conclusion: The regularity of QDs modified with functional group is that inhibition of TGA-modified higher than Cys-modified. Inhibition exhibited dose-dependent for Cys-modified while exhibited time-dependent for TGA-modified. The regularity of CdTe-QDs with ZnS or not is that the inhibition of Cys-CdTe/ZnS was higher than Cys-CdTe while TGA-CdTe/ZnS and TGA-CdTe were consistent.

The Differences in Alcohol Use between Urban and Rural Students of Inner Mongolia Medical University, China

Objective: The purpose of this study was to evaluate the difference in alcohol use between urban and rural students of Inner Mongolia Medical University. Methods: A cross-sectional census was conducted on medical students on campus in 2013. We use multivariate logistic regression models to assess the factors associated with alcohol use. We further use chi-square test assess on differences in alcohol use between urban and rural people among significance factors in logistic regression models. Results: The prevalence of alcohol use among students in rural area was higher than that in urban area (p = 0.016). Alcohol use was associated with Gender, monthly expenses, residence, ethnic and faculty. The odds of alcohol use for Mongolia students were 1.139 times higher than that for Han students. The prevalence of alcohol consumption among students from pharmacy or Traditional Chinese Medicine and Mongolian Medicine faculties in rural area was higher than that among student in urban area (p = 0.03;p = 0.001). The prevalence of alcohol use among female students in rural area was higher than that among female students in urban area (p < 0.043). The proportion of alcohol use among students with <600 in rural area was higher than that among students in urban area (p < 0.001). Conclusion: Considering the differences in the prevalence of alcohol use between rural area and urban area, university administrators aiming at students from various regions develop various approaches.

Cytotoxicity of Mongolian Medicine <i>Aconitum kusnezoffii</i>

Aconitum kusnezoffii used as an analgesic and anti-inflammatory. It is often used not only in Mongolian medicine but also in traditional Chinese medicine. However, there are few studies on its impact of inflammatory cytokines. This study explored the effects of Aconitum kusnezoffii in vitro used human colon cancer (Caco-2) cells. Cytotoxicity was assessed by measuring effects on expression of IL-1β, IL-6, IL-8, and TNF-α used enzyme-linked immunosorbent assay (ELISA). In vitro study demonstrated that incubation of Caco-2 cells with some kinds of Aconitum kusnezoffii at some concentrations inhibit secretion of TNF-α and FAXIU ACONITUM KUSNEZOFFII could inhibit the secretion of IL-1β. While IL-6 and IL-8 levels were unaffected after 24 h of treatment with Aconitum kusnezoffii, qujian Aconitum kusnezoffii, faxiu Aconitum kusnezoffii.

Application of a Quality Control Circle to Reduce the Wait Times between Continuous Surgeries

Purpose: To investigate how to shorten patient wait times between continuous ocular operations and to evaluate the influence of a quality control circle(QCC) on operating room management.Methods:.QCC management was established to conduct activities..Clinical data were collected to analyze the causes of long wait times between continuous surgeries. Effective measures were undertaken correspondingly.Results:.The staff from QCC actively undertook measures that would significantly shorten patient wait times between continuous ocular surgeries(P<0.05).Conclusion:.Multiple measures,.such as setting up a QCC,enhancing the arrangement of surgical procedures,.establishing effective communication channels,.optimizing human resources, and integrating the use of instruments, can effectively shorten patient wait times between continuous vitreous or retinal surgeries.

Influence of Psychological Intervention before Emergent Ocular Trauma Surgery on Patients' Negative Emotions

Purpose:.To investigate the effect of preoperative psychological intervention on alleviating negative emotions in patients undergoing emergent ocular trauma surgery.Methods:..A total of 100 patients undergoing emergent ocular trauma surgery were selected using convenience sampling and randomly divided into control(n=49) and experimental(n =51) groups. Patients in the control group received conventional nursing and their counterparts in the observation group were treated with individualized psychological interventions including psychological support, relaxation training, and humanistic care based on conventional nursing care..Self-rating anxiety scale(SAS), self-rating depression scale(SDS), and fear visual analog scale(FVAS) scores were statistically compared between the two groups.Results:.The scores of SAS, SDS, and FAVS were significantly lower in the experimental group than in the control group(all P<0.001).Conclusion:.Comprehensive psychological intervention effectively eliminates negative emotions in patients undergoing emergent ocular trauma surgery and accelerates their physical and mental recovery.

Molecular mechanisms of seasonal photoperiod effects of the pineal gland on the hippocampus in rats

Background:Based on the theory of“five Zang-organs corresponding to the seasons”in traditional Chinese medicine(TCM),physiological functions including emotions vary with the seasons.We aimed to investigate the seasonal photoperiod effects of melatonin(MT)released from the pineal gland on the MT receptor(MTR)-Gs/Gi-cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)-cAMP response element-binding protein(CREB)signaling pathway in the hippocampus.Methods:Rats were divided into three groups:control,operation(surgery with pineal gland removal),and pseudo-operation groups(same surgery as operation group but without removing pineal gland),and fed at specific time across the four seasons.The levels of MTR,adenylate cyclase(AC),cAMP,PKA,and CREB in the hippocampus were analyzed using ELISA.The concentrations of Gs and Gi were analyzed using Western blot.The expression of CREB mRNA was detected by PCR.Results:For intragroup comparisons,compared with spring,the levels of Gs/Gi in the control group were higher in summer,autumn,and winter(P=.009 in summer;P<.001 in autumn and winter);the levels of MTR,cAMP,PKA,and CREB in the control group were significantly higher in autumn and winter than in spring(all P<.001).The levels of MTR,cAMP,PKA,and CREB in each season were significantly lower in the operation group than in the control group(all P<.05).Significant differences were noted in Gs/Gi levels between the operation group and control group in spring,autumn,and winter(all P<.05).Conclusion:Our findings suggest that MTR-Gs/Gi-cAMP-PKA-CREB signaling pathway is involved in the seasonal photoperiod effects of the pineal gland on the hippocampus and may underpin seasonal changes in emotions.It can support the prevention and treatment of the seasonal onset of mental disorders,and enrich the theory of“five Zang-organs corresponding to the seasons”.

Seasonal photoperiodic influence of pineal melatonin on hypothalamic-pituitary-adrenal axis-hippocampal-receptor in male rats

Background: Based on the effect of seasonal changes on human visceral function, this study investigated the impact of seasonal photoperiod of the pineal body on hypothalamic-pituitary-adrenal axis-hippocampal-receptor in rats, aiming to reveal the mechanism by which pineal gland melatonin regulates the seasonal secretion of hippocampal neurotransmitters.Methods: Vernal equinox, summer solstice, autumn equinox, and winter solstice were selected as four experimental time points, and rats were randomly divided into normal control group, sham operation group, and pinealectomized group. The seasonal changes in corticotropin-releasing hormone(CRH),adrenocorticotropic hormone(ACTH), corticosterone, hypothalamic melatonin receptor(MTR), and hippocampal corticosterone receptor(CORTR) were examined by enzyme-linked immunosorbent assay.Results: Comparing the same group between different seasons, we showed that in the normal control group, CRH, ACTH, corticosterone, and MTR were higher, while CORTR was lower in autumn and winter than in spring(all P <.05). Compared with the normal control group, the pinealectomized group showed higher levels of corticosterone(P =.01), MTR(P =.01), and CORTR(P =.03) during spring;reduced levels of MTR and CORTR(both P <.001) during summer;higher levels of ACTH(P =.001) and MTR(P <.001),and lower levels of CRH(P =.001), corticosterone(P <.001), and CORTR(P =.003) during autumn;and lower levels of CRH(P <.001) and MTR(P =.004), and higher level of ACTH(P <.001) in winter.Conclusions: Seasonal photoperiod acts on the pineal gland to secrete different levels of melatonin,resulting in seasonal changes in the hypothalamic-pituitary-adrenal axis-hippocampal-receptor, which may be the pathophysiological basis for the onset of seasonal affective disorder.

An Improved Parameter Dimensionality Reduction Approach Based on a Fast Marching Method for Automatic History Matching

History matching is a critical step in reservoir numerical simulation algorithms.It is typically hindered by difficulties associated with the high-dimensionality of the problem and the gradient calculation approach.Here,a multi-step solving method is proposed by which,first,a Fast marching method(FMM)is used to calculate the pressure propagation time and determine the single-well sensitive area.Second,a mathematical model for history matching is implemented using a Bayesian framework.Third,an effective decomposition strategy is adopted for parameter dimensionality reduction.Finally,a localization matrix is constructed based on the single-well sensitive area data to modify the gradient of the objective function.This method has been verified through a water drive conceptual example and a real field case.The results have shown that the proposed method can generate more accurate gradient information and predictions compared to the traditional analytical gradient methods and other gradient-free algorithms.

Surgical Cooperation during Implantation of a Boston type-Ⅰ Keratoprosthesis

This study was designed to summarize the key points of surgical cooperation involving penetrating corneal transplantation combined with implantation of keratoprosthesis. Preoperative preparation and intraoperative procedures were fully implemented to ensure cooperation with the physicians,.to observe the the severity of the disease, and to guarantee the success of the surgery.

Death Characteristics of Neurological Diseases in Inner Mongolia between 2008 and 2015

Background: There are no studies of death from neurological diseases found, however, neurological diseases were the leading cause of disability-adjusted life years in 2015 worldwide. Aim: The scientific aim of this study is to analyze the death characteristics of neurological diseases in Inner Mongolia occurring between 2008 and 2015. Methods: The data collected from Death Registry System (DRS) were categorized by gender, ethnicity, age, and death location. The subjects were divided into age groups for every 10 years from the age of 20. Mortality and gender: age-specific mortality was calculated for every 100,000 people from 2008 to 2015. Results: We found that Alzheimer’s disease has the highest proportion which equated to over one-fifth of all neurological diseases. Males displayed a higher mortality rate than females in all neurological diseases. The neurological diseases mortality showed a total potential year of life lost (PYLL) of about 20,151 years, and it was 2.03 times higher for male than that for female. The average potential years of life lost (APYLL) showed 17.72 years, and APYLL in males was 3.34 years longer than in females. More than 60% of the deaths resulting from the neurological disease occur at home for both males and females. Conclusion: Alzheimer disease is the most serious disease of all neurological diseases, however, cerebral palsy and epilepsy also displayed the highest loss of life for residents. Mortality of neurological diseases was generally higher in males than in females, and this increased with age.

The Effect of Sodium Nitrite on Induction of Apoptosis in Human Gastric Adenocarcinoma Epithelia (AGS) Cells

To examine the cytocidal effect of sodium nitrite on the cancer cell, we subjected human gastric adenocarcinoma epithelia (AGS) cells to various experimentation following exposure to sodium nitrite, and measured the resulting changes in the levels of cell death, lactate dehydrogenase (LDH) release, and caspase-3, -6, -8, and -9 activities. Our data revealed that, in AGS cells, treatment with ≥6.25 mM sodium nitrite for 8 h resulted in an obvious increase in cell death. LDH release was also markedly increased following sodium nitrite treatment, but at a concentration of ≥6.25 mM for 24 h. This increasing trend showed a positive correlation (r = 0.9564, P < 0.05). In addition, we detected pronounced increases in caspase activities with various concentrations of sodium nitrite: caspase-3 at ≥25 mM for 1 h, ≥12.5 mM for 3 h and 6 h;caspase-9 at 50 mM for 1 h and 3 h, and ≥6.25 mM for 6 h;and caspase-6 at 50 mM for 1 h and 3 h. We did not however, detect any observable increase in the activity of caspase-8 following sodium nitrite treatment at any concentration or for any duration of treatment in this study. This data demonstrates that, in AGS cells, higher concentrations or longer durations of treatment with sodium nitrite could exhibit a cytocidal effect, and that sodium nitrite could induce apoptosis via activation of the caspase-9, caspase-3 cascade (intrinsic pathway) and caspase-6.

The Description of Pancreatic Cancer Death in Inner Mongolia 2008-2014

Objective: The study aimed to assess the characteristics of pancreatic cancer deaths and the relationship between socio-demographic status and mortality risk of pancreatic cancer in Inner Mongolia. Method: We obtained our data for 2008-2014 from the Death Registry System of Inner Mongolia. We calculated the mortality rate, potential years of life lost (PYLL) and average years of life lost (AYLL) for men and women. We collected socio-demographic characteristics including education level, ethnicity, region, and occupation. Logistic regression models were employed to analyze risk factors of pancreatic cancer. Results: The average mortality rate of pancreatic cancer was 4.42/100,000 in Inner Mongolia during 2008 to 2014. Mortality rate in men was higher in all age groups compared with those in women. The highest mortality rate was 1.3 times than the lowest mortality rate for men and 1.6 times for women during seven years. Average AYLL in women were more than 3.4 years compared with that in men. PYLLR in women was fluctuated from 0.41 to 0.63 per thousand during 2008 to 2014. In eastern region, no occupation and high education level had a higher risk of pancreatic cancer. Conclusion: In Inner Mongolia, the mortality rate associated with pancreatic cancer was higher in men compared with in women. More than 65 years old groups had high death risk for pancreatic cancer. Average years of life lost for women were significantly higher than that for men. We should pay more attention to the older men.

Analysis of Cause of Death in Inner Mongolia of China, 2008-2014

Objective: The aim of our study was to analyze the character of cause of death in Inner Mongolia of China from 2008 to 2014. Methods: We collected data from monitoring points of the Death Registry System (DRS) in Inner Mongolia. We calculated the mortality rates by gender, year and age-specific. We calculated the proportion, the mortality rate and potential years of life lost (PYLL) of various system deaths. Results: During the period 2008-2014, the average crude mortality rate of all cause of death was 539.33/105. The mortality rate increased semilogarithm linearly with age. The top four system deaths were circulatory system, neoplasm, respiratory system and injury. In 2014, the mortality rates of circulatory system were increased and the mortality rates of certain infectious and parasitic diseases, neoplasms, respiratory system, genitourinary system and injury were decreased compared to those in 2008. Conclusion: Through analysis the indicators of proportion, the mortality rate and PYLL indicated that health status of a population in Inner Mongolia was at a better level.

Document Analysis of Correlation between Climate and Stroke

Aim: The aim of the research is to determine characteristic of the correlation between climate and stroke through the analysis of relevant documents. Methods: We found 115 researches of temperature and season on stroke mortality/incidence and these were categorized according to location, meteorology, date span, data source and research sites’ latitudes. We divided the globe into 5 temperature zones based on latitude ranges: 0 - 10, 10 - 23.5, 23.5 - 40, 40 - 50, and >50 degrees, and allotted a zone to each country. Stroke mortality by five temperature zones was calculated per 100,000 people. Results: 70% of the researches came from latitudes greater than 40 degrees with 92% of researches located in Europe, USA, and Asia. The mortality range was 42 - 63 per 105 individuals within latitudes 0 - 40 degrees. In latitudes 40 - 66.5 degrees, a linear upward trend (y = 69.82x &#8722;22.823, R2 = 0.99) was noticed. More than 75% of the research reports indicated a negative correlation between climate and stroke, and the proportion was almost 6 and 7 times greater than that of the fluctuation and non-correlation, respectively. The most frequently used research methods were regression analysis and time series analysis. Conclusion: All of the research results confirmed that lower temperature is associated with higher mortality and incidence of stroke, while higher latitude is correlated with higher stroke mortality, consistent with the temperature zones.

Analysis of the distribution characteristics of enterovirus types based on environmental surveillance from 2013 to 2021 in Fujian Province, China

Environmental surveillance (ES) is a useful approach for monitoring circulating viruses, including polioviruses (PVs) and non-polio enteroviruses (NPEVs). In this study, the results of nine years of ES from 2013 to 2021 at six sampling sites in three cities in Fujian Province, China, were summarized. It showed that the sewage samples contained abundant viruses, but the positive rate was affected by different sampling sites. From the 520 samples, 431 PVs, 1,713 NPEVs, and 281 human adenoviruses (HAdVs) were isolated. PV isolates had been markedly affected following the adjustment of the immunization strategy. All but one PV isolate were Sabin-like strains without wild PVs. One isolate was vaccine-derived PV type 3 with 10 variation points in theVP1 region. After May 2016, PV type 2 was no longer detected, and PV type 3 became a superior serotype. Of 1,713 NPEVs, 24 serotypes were identified, including echovirus11 (E11), E6, coxsackievirus B3 (CVB3), CVB5, E7, and E3 were the predominant serotypes (37.65%, 20.96%, 11.50%, 8.87%, 8.23%, and 7.06%, respectively). The temporal dynamic of the six common serotypes was inconsistent. E3 was frequently isolated, but the number of isolates was low, with no obvious peaks. E6, E7, and CVB3 exhibited periodic changes with a high peak every three to four years, and E11 only had one high peak lasting four years. Summer-fall peaks of the echoviruses and spring-winter peaks of CVB were observed in the monthly distribution of virus isolation. The infectious isolates of various serotypes of different species identified from the sewage samples showed that ES is an essential part of pathogen surveillance.

Observation on the aerosol and ozone precursors in suburban areas of Shenzhen and analysis of potential source based on MAX-DOAS

Long-term stereoscopic observations of aerosol,NO2,and HCHO were carried out at the Yangmeikeng(YMK)site in Shenzhen.Aerosol optical depths and NO2 vertical column concentration(NO2 VCD)derived from MAX-DOAS were found to be consistent with other datasets.The total NO2 VCD values of the site remained low,varying from 2×10^(15)to 8×10^(15)mol/cm^(2),while the HCHO VCD was higher than NO2 VCD,varying from 7×10^(15)to 11×10^(15)mol/cm^(2).HCHO VCD was higher from September to early November than that was from mid-late November to December and during February 2021,in contrast,NO2 VCD did not change much during the same period.In January,NO2 VCD and HCHO VCD were both fluctuating drastically.High temperature and HCHO level in the YMK site is not only driving the ozone production up but alsomay be driving up the ozone concentration as well,and the O_(3)production regime in the YMK site tends to be NOx-limited.At various altitudes,backward trajectory clustering analysis and Potential Source Contribution Function(PSCF)were utilized to identify possible NO2 and HCHO source locations.The results suggested that the Huizhou-Shanwei border and the Daya Bay Sea area were the key potential source locations in the lower(200 m)and middle(500 m)atmosphere(WPSCF>0.6).The WPSCF valuewas high at the 1000maltitude whichwas closer to the YMKsite than the near ground,indicating that the pollution transport capability in the upper atmosphere was limited.

当代中国托马斯·品钦作品研究评述

从易丹1991年在《外国文学评论》上完成第一篇以托马斯·品钦为研究对象的专题论文至今,当代中国品钦作品研究已经走过近三十年的历程。品钦形象由陌生的'黑色幽默派'作家到当代美国后现代作家的核心符码,与之相随的是其作品研究也经历了中国文学批评范式的多次转变。从整体上来看,当代中国的品钦作品研究,一方面凸显了其从感性的'追寻'到理性'熵'的探寻,从'黑色幽默'到'叙事'的演变,而由'历史维度'到'空间维度'的研究拓展为品钦'后现代'核心符码起了至关重要的作用;另一方面体现了中国语境下的美国文学研究逐渐呈现出跨学科的发展态势,这一转变与人文学科的整体走向以及中国学者的整体认知密切相关。

A novel bioremediation strategy for petroleum hydrocarbon pollutants using salt tolerant Corynebacterium variabile HRJ4 and biochar

The present work aimed to develop a novel strategy to bioremediate the petroleum hydrocarbon contaminants in the environment.Salt tolerant bacterium was isolated from Dagang oilfield,China and identified as Corynebacterium variabile HRJ4 based on 16 S r RNA gene sequence analysis.The bacterium had a high salt tolerant capability and biochar was developed as carrier for the bacterium.The bacteria with biochar were most effective in degradation of n-alkanes（C16,C18,C19,C26,C28） and polycyclic aromatic hydrocarbons（NAP,PYR） mixture.The result demonstrated that immobilization of C.variabile HRJ4 with biochar showed higher degradation of total petroleum hydrocarbons（THPs） up to 78.9%after 7-day of incubation as compared to the free leaving bacteria.The approach of this study will be helpful in clean-up of petroleum-contamination in the environments through bioremediation process using eco-friendly and cost effective materials like biochar.

Analysis of COVID-19 Guideline Quality and Change of Recommendations:A Systematic Review

Background.Hundreds of coronavirus disease 2019(COVID-19)clinical practice guidelines(CPGs)and expert consensus statements have been developed and published since the outbreak of the epidemic.However,these CPGs are of widely variable quality.So,this review is aimed at systematically evaluating the methodological and reporting qualities of COVID-19 CPGs,exploring factors that may influence their quality,and analyzing the change of recommendations in CPGs with evidence published.Methods.We searched five electronic databases and five websites from 1 January to 31 December 2020 to retrieve all COVID-19 CPGs.The assessment of the methodological and reporting qualities of CPGs was performed using the AGREE II instrument and RIGHT checklist.Recommendations and evidence used to make recommendations in the CPGs regarding some treatments for COVID-19(remdesivir,glucocorticoids,hydroxychloroquine/chloroquine,interferon,and lopinavir-ritonavir)were also systematically assessed.And the statistical inference was performed to identify factors associated with the quality of CPGs.Results.We included a total of 92 COVID-19 CPGs developed by 19 countries.Overall,the RIGHT checklist reporting rate of COVID-19 CPGs was 33.0%,and the AGREE II domain score was 30.4%.The overall methodological and reporting qualities of COVID-19 CPGs gradually improved during the year 2020.Factors associated with high methodological and reporting qualities included the evidence-based development process,management of conflicts of interest,and use of established rating systems to assess the quality of evidence and strength of recommendations.The recommendations of only seven(7.6%)CPGs were informed by a systematic review of evidence,and these seven CPGs have relatively high methodological and reporting qualities,in which six of them fully meet the Institute of Medicine(IOM)criteria of guidelines.Besides,a rapid advice CPG developed by the World Health Organization(WHO)of the seven CPGs got the highest overall scores in methodological(72.8%)and reporting qualities(83.8%).Many CPGs covered the same clinical questions(it refers to the clinical questions on the effectiveness of treatments of remdesivir,glucocorticoids,hydroxychloroquine/chloroquine,interferon,and lopinavirritonavir in COVID-19 patients)and were published by different countries or organizations.Although randomized controlled trials and systematic reviews on the effectiveness of treatments of remdesivir,glucocorticoids,hydroxychloroquine/chloroquine,interferon,and lopinavir-ritonavir for patients with COVID-19 have been published,the recommendations on those treatments still varied greatly across COVID-19 CPGs published in different countries or regions,which may suggest that the CPGs do not make sufficient use of the latest evidence.Conclusions.Both the methodological and reporting qualities of COVID-19 CPGs increased over time,but there is still room for further improvement.The lack of effective use of available evidence and management of conflicts of interest were the main reasons for the low quality of the CPGs.The use of formal rating systems for the quality of evidence and strength of recommendations may help to improve the quality of CPGs in the context of the COVID-19 pandemic.During the pandemic,we suggest developing a living guideline of which recommendations are supported by a systematic review for it can facilitate the timely translation of the latest research findings to clinical practice.We also suggest that CPG developers should register the guidelines in a registration platform at the beginning for it can reduce duplication development of guidelines on the same clinical question,increase the transparency of the development process,and promote cooperation among guideline developers all over the world.Since the International Practice Guideline Registry Platform has been created,developers could register guidelines prospectively and internationally on this platform.