According to the World Health Organization (WHO) manual, sperm concentration should be measured using an improved Neubauer hemocytometer, while sperm motility should be measured by manual assessment. However, in China, thousands of laboratories do not use the improved Neubauer hemocytometer or method; instead, the Makler counting chamber is one of the most widely used chambers. To study sources of error that could impact the measurement of the apparent concentration and motility of sperm using the Makler counting chamber and to verify its accuracy for clinical application, 67 semen samples from patients attending the Department of Andrology, West China Second University Hospital, Sichuan University (Chengdu, China) between 13 September 2023 and 27 September 2023, were included. Compared with applying the cover glass immediately, delaying the application of the cover glass for 5 s, 10 s, and 30 s resulted in average increases in the sperm concentration of 30.3%, 74.1%, and 107.5%, respectively (all P < 0.0001) and in the progressive motility (PR) of 17.7%, 30.8%, and 39.6%, respectively (all P < 0.0001). However, when the semen specimens were fixed with formaldehyde, a delay in the application of the cover glass for 5 s, 10 s, and 30 s resulted in an average increase in the sperm concentration of 6.7%, 10.8%, and 14.6%, respectively, compared with immediate application of the cover glass. The accumulation of motile sperm due to delays in the application of the cover glass is a significant source of error with the Makler counting chamber and should be avoided.
Humans ; Male ; Sperm Motility/physiology* ; Sperm Count ; Semen Analysis/methods* ; Spermatozoa/physiology* ; Time Factors

Objective To investigate a rapid detection method for compressed Nitrous oxide(N2O).Methods The GC-MS system was employed under conventional chromatographic conditions(without replacing standard columns or utilizing headspace sampling)by directly injecting a small gas sample for analysis.N2O identification was performed via NIST spectral library matching,while qualitative and quantitative purity assessments were achieved by monitoring the relative abundance variation of the characteristic fragment ion m/z 30 to eliminate CO2 interference.Results The fragment ion m/z 30 demonstrated specificity for N2O identification.A linear correlation was observed between the peak area of m/z 30 and N2O purity(y=22.741x-1.4565,R2=0.912 6),enabling quantitative purity determination.Additionally,the abundance of m/z30 exhibited a correlation with N2O in CO2 mixtures(y=0.7787x-0.0387,R2=0.722 2).Conclusion Conventional N2O identification typically requires dedicated GC-MS systems,gas-specific chromatographic columns,and headspace sampling.This study successfully utilized routine chromatographic conditions for organic toxicant screening to achieve rapid N2O analysis.The proposed method holds practical significance for compressed N2O identification in forensic and analytical applications.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

Objective To investigate a rapid detection method for compressed Nitrous oxide(N2O).Methods The GC-MS system was employed under conventional chromatographic conditions(without replacing standard columns or utilizing headspace sampling)by directly injecting a small gas sample for analysis.N2O identification was performed via NIST spectral library matching,while qualitative and quantitative purity assessments were achieved by monitoring the relative abundance variation of the characteristic fragment ion m/z 30 to eliminate CO2 interference.Results The fragment ion m/z 30 demonstrated specificity for N2O identification.A linear correlation was observed between the peak area of m/z 30 and N2O purity(y=22.741x-1.4565,R2=0.912 6),enabling quantitative purity determination.Additionally,the abundance of m/z30 exhibited a correlation with N2O in CO2 mixtures(y=0.7787x-0.0387,R2=0.722 2).Conclusion Conventional N2O identification typically requires dedicated GC-MS systems,gas-specific chromatographic columns,and headspace sampling.This study successfully utilized routine chromatographic conditions for organic toxicant screening to achieve rapid N2O analysis.The proposed method holds practical significance for compressed N2O identification in forensic and analytical applications.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

This study explored the antibiotic resistance and resistance gene carriage of 140 Salmonella strains isolated from environmental sewage in Guangzhou city between March 1,2022,and November 30,2022.The micro broth dilution method was used to select 17 antibiotics for susceptibility testing.According to whole genome sequencing results,the CARD resistance database was used to obtain corresponding resistance genes.High antimicrobial resistance rates above 80％were observed a-gainst ampicillin,tetracycline,streptomycin,chloramphenicol,and cotrimoxazole.The intermediation rate of polymyxin E and ciprofloxacin exceeded 60％.The multiple drug resistance status was severe,and the rate of multiple drug resistance was as high as 92.86％.The strains carried multiple types of resistance genes,particularly for aminoglycosides,with a carriage rate as high as 92.68％.The resistance of Salmonella in environmental wastewater in Guangzhou to one or more drugs was severe,and the overall multi-drug resistance rate gradually increased over time.The resistance spectrum was diverse,and the resistance mechanism,mediated by mobile genetic elements such as re-sistance genes,was found to be the main cause of resistance to one or more drugs.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective To analyze the status and trend for the mortality and DALY rates of child growth failure (CGF) in children aged < 5 years in China from 1990 to 2019, so as to provide a scientific basis for CGF prevention and control. Methods The mortality and DALY rates of CGF in children aged < 5 years from 1990 to 2019 were obtained from GBD 2019. The changes of these indicators with the years in China , the United States, Japan, Russia, India and the global were compared and analyzed. Results In 2019, the mortality of child wasting, child stunting and child underweight in children aged < 5 years in China were 9.62/100 000, 1.23/100 000, and 1.29/100 000 respectively, the mortality rates were 867.50/100 000 , 129.23/100 000 , and 112.87/100 000 rescpectively, higher than those of the United States, Japan, and Russia, and far lower than those of India and the global. The disease burden of three types of CGF were all higher in males than females, and higher in children aged < 1 years than children aged 1-4 years. From 1990 to 2019, the mortality and DALY rates of CGF in children aged < 5 years in China decreased from 300.41/100 000 and 26 445.38/100 000 to 10.49/100 000 and 943.57/100 000, respectively. China had the largest drop rate compared with all analyzed countries. As for children aged < 5 years in China, the DALY rate of lower respiratory infection ranked first in all the diseases caused by CGF. Conclusion From 1990 to 2019, the disease burden of CGF in children aged < 5 years has shown a significant decrease in China , but it is still far behind the developed countries. In the future, more attention should be paid to the problems of child growth in hope of reducing the mortality and DALY rates of CGF.

OBJECTIVES: To investigate the incidence of extrauterine growth retardation (EUGR) and its risk factors in very preterm infants (VPIs) during hospitalization in China. METHODS: A prospective multicenter study was performed on the medical data of 2 514 VPIs who were hospitalized in the department of neonatology in 28 hospitals from 7 areas of China between September 2019 and December 2020. According to the presence or absence of EUGR based on the evaluation of body weight at the corrected gestational age of 36 weeks or at discharge, the VPIs were classified to two groups: EUGR group (n=1 189) and non-EUGR (n=1 325). The clinical features were compared between the two groups, and the incidence of EUGR and risk factors for EUGR were examined. RESULTS: The incidence of EUGR was 47.30% (1 189/2 514) evaluated by weight. The multivariate logistic regression analysis showed that higher weight growth velocity after regaining birth weight and higher cumulative calorie intake during the first week of hospitalization were protective factors against EUGR (P<0.05), while small-for-gestational-age birth, prolonged time to the initiation of total enteral feeding, prolonged cumulative fasting time, lower breast milk intake before starting human milk fortifiers, prolonged time to the initiation of full fortified feeding, and moderate-to-severe bronchopulmonary dysplasia were risk factors for EUGR (P<0.05). CONCLUSIONS It is crucial to reduce the incidence of EUGR by achieving total enteral feeding as early as possible, strengthening breastfeeding, increasing calorie intake in the first week after birth, improving the velocity of weight gain, and preventing moderate-severe bronchopulmonary dysplasia in VPIs.
Female ; Fetal Growth Retardation ; Gestational Age ; Hospitalization ; Humans ; Incidence ; Infant ; Infant, Newborn ; Infant, Premature ; Infant, Very Low Birth Weight ; Prospective Studies ; Risk Factors