Objective To explore the polymorphism of tyrosinase (TYR) and melanocortin 1 receptor (MC1R) genes and their mRNA expression levels in relation to coat-color phenotypes in guinea pigs, providing genetic markers for locating dominant traits in guinea pigs. Methods A total of 57 self-bred ordinary-level guinea pigs were selected and divided into three groups based on coat color: white (n=22), variegated (n=22) and black (n=13). The guinea pigs were euthanized with an overdose of pentobarbital sodium via intraperitoneal injection. DNA was then extracted from the dorsal skin tissue. Polymorphism in the coding sequence (CDS) of the exons of the TYR and MC1R genes in each group was detected by cloning and sequencing. The mRNA expression of the two genes in skin tissues was detected by real-time fluorescent quantitative PCR to investigate the relationship between these genes and guinea pig coat color. Results A single nucleotide polymorphism (SNP) site was found in the CDS region of TYR exon Ⅰ, where the base A was replaced by G. All white guinea pigs had the G/G genotype for TYR, while no deep-colored (variegated and black) guinea pigs exhibited the G/G genotype for TYR. Most deep-colored guinea pigs had the A/A genotype, and a few had A/G genotype. The A/A genotype frequency in black guinea pigs was higher than in variegated guinea pigs. A 2 760 bp sequence deletion was identified in the exon of the MC1R gene, marked as the - gene, with non-deleted samples marked as N gene. Most white guinea pigs had the -/- genotype for MC1R, variegated guinea pigs mainly had the -/N genotype, and black guinea pigs mainly had the N/N genotype, with a few showing the -/N. The TYR gene expression level was higher in white guinea pigs, lower in variegated guinea pigs, and intermediate in black guinea pigs, but there was no significant difference among the three groups (P>0.05). The MC1R gene expression level in white guinea pigs was extremely low, while both variegated and black guinea pigs showed significantly higher levels than white guinea pigs (P<0.01). Black guinea pigs showed significantly higher levels than variegated guinea pigs (P<0.05). ConclusionThe TYR and MC1R genes synergistically regulate coat color of guinea pigs. The G-site mutation in the TYR gene may lead to albinism, and the change of N-site in the MC1R gene affects the depth of the coat color.

Objective:To measure the distance between the fetal bladder neck and the rectal end using prenatal MRI and analyze the developmental patterns of this distance and the gender differences in the second and third trimesters of pregnancy.Methods:This retrospective cohort study involved fetuses born at Guangzhou Women and Children's Medical Center, Guangzhou Medical University after regular prenatal examinations from January 2019 to December 2022 and confirmed to have typical anorectal structures after birth. These fetuses had undergone prenatal MRI examinations for reasons other than abdominal issues. The morphology of the fetuses' colons, rectums, and bladders was observed, and the vertical distance between the bladder neck and the rectal end was measured on sagittal T1weighted imaging. Differences in the distance between male and female fetuses were analyzed. The fetuses were divided into five groups based on their gestational age at the time of MRI examination (23-24 weeks, >24-26 weeks, >26-28 weeks, >28- 30 weeks, and >30-32 weeks), and the changes in the distance with gestational age were analyzed. Statistical analysis was performed using t-test, Kruskal-Wallis test, and Spearman correlation analysis. Pairwise comparisons among multiple groups were conducted using the Bonferroni method. Results:(1) A total of 142 fetuses were included in this study, all of which were singletons, with 73 males (51.4%) and 69 females (48.6%). The gestational age at the MRI examination was 28 weeks (26-30 weeks). (2) All fetuses had meconium filling the entire rectum and colon, with the rectal end located 0.570-2.610 cm below the bladder neck. (3) The distance between the bladder neck and the rectal end was shorter in male fetuses than in female fetuses [(1.140±0.261) vs. (1.519±0.405) cm, t=－6.58, P<0.001]. (4) In female fetuses, four pairs of groups showed statistically significant differences in the distance (23-24 weeks group vs. >26-28 weeks, >28- 30 weeks, and >30-32 weeks groups, and >24-26 weeks group vs. >30-32 weeks group). However, only two groups of male fetuses (23-24 weeks group vs. >28-30 weeks group) had statistically significant differences in the distance (all P<0.005). (5) The distance was moderately correlated with gestational age in male fetuses ( r=0.42, P<0.001), but they were strongly correlated in female fetuses ( r=0.66, P<0.001). Conclusions:The distance between the bladder neck and the rectal end in fetuses shows certain developmental patterns and gender differences in pregnancy's second and third trimesters. The correlation between the value and gestational age is stronger in female fetuses.

Objective To explore the influencing factors of olfactory dysfunction in patients with Parkinson's disease(PD)and conduct a systematic review and Meta-analysis.Methods Articles on factors influencing olfactory dysfunction in PD were retrieved from databases including SinoMed,VIP,China National Knowledge Infrastructure,Wanfang Data Knowledge Service Platform,Web of Science,PubMed,Cochrane,Embase,and MEDLINE.The search period spanned from the inception of each database to November 30,2024.Results A total of 13 articles(with a total sample size of 2465)were included,with a total of 18 influencing factors summarized as two themes:core features and progression factors of PD,and individual background and environmental interaction factors.Meta-analysis showed that age(MD=1.01,95％CI:-0.46-2.49,P=0.18),smoking(OR=0.88,95％CI:0.57-1.37,P=0.57),and constipation(OR=1.22,95％CI:0.38-3.93,P=0.74)were not factors affecting olfactory dysfunction in PD patients.Conclusion Factors influencing olfactory dysfunction in PD are predominantly associated with non-motor symptoms.Intervention strategies targeting non-motor symptoms(such as improving sleep quality,vitamin D supplementation,and early cognitive training)may provide novel approaches for delaying the progression of olfactory dysfunction.

[Purpose]To analyze the prevalence characteristics and disease burden of lung cancer in Hebei cancer registration areas from 2012 to 2020.[Methods]Lung cancer data were collected from the Hebei Provincial Cancer Registry from 2012 to 2020.The crude incidence/mortality rates,age-standardized incidence/mortality rates by Chinese standard population(ASIRC/ASMRC)and by world standard population(ASIRW/ASMRW)were calculated.The Joinpoint model was used to calculate the annual percentage change(APC)and average annual percentage change(AAPC).Years of life lost(YLL)and years lived with disability(YLD)and the disability-adjusted life years(DALY)were calculated.[Results]From 2012 to 2020,the ASIRW of lung cancer in Hebei can-cer registration areas was 33.13/105,44.56/105 for men and 22.54/105 for women,respectively;the incidence rates of urban and rural areas were 29.05/105 and 33.52/105,respectively.The incidence rates increased with ages,reaching a peak in the age group of 80～84 years old.There was a de-creasing trend in the ASIRW of lung cancer(AAPC=-3.99％,P＜0.05).From 2012 to 2020,the ASMRW of lung cancer was 25.80/105,36.56/105 for men and 15.96/105 for women,respectively;the mortality rates of urban and rural areas were 25.14/105 and 26.12/105,respectively.The mor-tality rates increase with ages,reaching a peak in the age group of 85 and above years old.There was a decreasing trend in the mortality of lung cancer(AAPC=-4.65％,P＜0.001)from 2012 to 2020.The DALY of lung cancer in Hebei Province from 2012 to 2020 was 484 194 person-years,with male accounting for 66.77％,female accounted for 33.23％,the DALY rate of lung cancer was 3.31‰,of which 35.57％in urban areas and 64.43％in rural areas.[Conclusion]Lung can-cer incidence and mortality rate in Hebei cancer registration areas from 2012 to 2020 showed a decreasing trend.The disease burden is gradually increasing with age in middle-aged and el-derly population.

Objective To explore the influencing factors of olfactory dysfunction in patients with Parkinson's disease(PD)and conduct a systematic review and Meta-analysis.Methods Articles on factors influencing olfactory dysfunction in PD were retrieved from databases including SinoMed,VIP,China National Knowledge Infrastructure,Wanfang Data Knowledge Service Platform,Web of Science,PubMed,Cochrane,Embase,and MEDLINE.The search period spanned from the inception of each database to November 30,2024.Results A total of 13 articles(with a total sample size of 2465)were included,with a total of 18 influencing factors summarized as two themes:core features and progression factors of PD,and individual background and environmental interaction factors.Meta-analysis showed that age(MD=1.01,95％CI:-0.46-2.49,P=0.18),smoking(OR=0.88,95％CI:0.57-1.37,P=0.57),and constipation(OR=1.22,95％CI:0.38-3.93,P=0.74)were not factors affecting olfactory dysfunction in PD patients.Conclusion Factors influencing olfactory dysfunction in PD are predominantly associated with non-motor symptoms.Intervention strategies targeting non-motor symptoms(such as improving sleep quality,vitamin D supplementation,and early cognitive training)may provide novel approaches for delaying the progression of olfactory dysfunction.

[Purpose]To analyze the prevalence characteristics and disease burden of lung cancer in Hebei cancer registration areas from 2012 to 2020.[Methods]Lung cancer data were collected from the Hebei Provincial Cancer Registry from 2012 to 2020.The crude incidence/mortality rates,age-standardized incidence/mortality rates by Chinese standard population(ASIRC/ASMRC)and by world standard population(ASIRW/ASMRW)were calculated.The Joinpoint model was used to calculate the annual percentage change(APC)and average annual percentage change(AAPC).Years of life lost(YLL)and years lived with disability(YLD)and the disability-adjusted life years(DALY)were calculated.[Results]From 2012 to 2020,the ASIRW of lung cancer in Hebei can-cer registration areas was 33.13/105,44.56/105 for men and 22.54/105 for women,respectively;the incidence rates of urban and rural areas were 29.05/105 and 33.52/105,respectively.The incidence rates increased with ages,reaching a peak in the age group of 80～84 years old.There was a de-creasing trend in the ASIRW of lung cancer(AAPC=-3.99％,P＜0.05).From 2012 to 2020,the ASMRW of lung cancer was 25.80/105,36.56/105 for men and 15.96/105 for women,respectively;the mortality rates of urban and rural areas were 25.14/105 and 26.12/105,respectively.The mor-tality rates increase with ages,reaching a peak in the age group of 85 and above years old.There was a decreasing trend in the mortality of lung cancer(AAPC=-4.65％,P＜0.001)from 2012 to 2020.The DALY of lung cancer in Hebei Province from 2012 to 2020 was 484 194 person-years,with male accounting for 66.77％,female accounted for 33.23％,the DALY rate of lung cancer was 3.31‰,of which 35.57％in urban areas and 64.43％in rural areas.[Conclusion]Lung can-cer incidence and mortality rate in Hebei cancer registration areas from 2012 to 2020 showed a decreasing trend.The disease burden is gradually increasing with age in middle-aged and el-derly population.

Objective:To measure the distance between the fetal bladder neck and the rectal end using prenatal MRI and analyze the developmental patterns of this distance and the gender differences in the second and third trimesters of pregnancy.Methods:This retrospective cohort study involved fetuses born at Guangzhou Women and Children's Medical Center, Guangzhou Medical University after regular prenatal examinations from January 2019 to December 2022 and confirmed to have typical anorectal structures after birth. These fetuses had undergone prenatal MRI examinations for reasons other than abdominal issues. The morphology of the fetuses' colons, rectums, and bladders was observed, and the vertical distance between the bladder neck and the rectal end was measured on sagittal T1weighted imaging. Differences in the distance between male and female fetuses were analyzed. The fetuses were divided into five groups based on their gestational age at the time of MRI examination (23-24 weeks, >24-26 weeks, >26-28 weeks, >28- 30 weeks, and >30-32 weeks), and the changes in the distance with gestational age were analyzed. Statistical analysis was performed using t-test, Kruskal-Wallis test, and Spearman correlation analysis. Pairwise comparisons among multiple groups were conducted using the Bonferroni method. Results:(1) A total of 142 fetuses were included in this study, all of which were singletons, with 73 males (51.4%) and 69 females (48.6%). The gestational age at the MRI examination was 28 weeks (26-30 weeks). (2) All fetuses had meconium filling the entire rectum and colon, with the rectal end located 0.570-2.610 cm below the bladder neck. (3) The distance between the bladder neck and the rectal end was shorter in male fetuses than in female fetuses [(1.140±0.261) vs. (1.519±0.405) cm, t=－6.58, P<0.001]. (4) In female fetuses, four pairs of groups showed statistically significant differences in the distance (23-24 weeks group vs. >26-28 weeks, >28- 30 weeks, and >30-32 weeks groups, and >24-26 weeks group vs. >30-32 weeks group). However, only two groups of male fetuses (23-24 weeks group vs. >28-30 weeks group) had statistically significant differences in the distance (all P<0.005). (5) The distance was moderately correlated with gestational age in male fetuses ( r=0.42, P<0.001), but they were strongly correlated in female fetuses ( r=0.66, P<0.001). Conclusions:The distance between the bladder neck and the rectal end in fetuses shows certain developmental patterns and gender differences in pregnancy's second and third trimesters. The correlation between the value and gestational age is stronger in female fetuses.

Spastic paraplegia type 4 (SPG4) is the most common type of autosomally inherited spastic paraplegia. Its main clinical features include typical simple hereditary spastic paraplegia, with neurological impairments limited to lower limb spasticity, hypertonic bladder dysfunction, and mild weakening of lower limb vibration sensation, without accompanying features such as nerve atrophy, ataxia, cognitive impairment, seizures, and muscle tone disorders. SPAST is the main pathogenic gene underlying SPG4, and various pathogenic SPAST variants have been discovered. This disease has featured a high degree of clinical heterogeneity, and the same pathogenic variant can have different age of onset and severity among patients and even within the same family. There is a lack of systematic research on the correlation between the genotype and phenotype of SPG4, and the pathogenic mechanism has remained controversial. This article has provided a review for the clinical characteristics, pathogenic gene characteristics, correlation between the genotype and phenotype, and pathogenic mechanism of this disease, with an aim to provide reference for its clinical diagnosis and treatment.

To investigate the prevalence and epidemiological characteristics of diabetic retinopathy (DR) in Yunnan Province, explore its risk factors, and provide a basis for the prevention and treatment of chronic complications of diabetes mellitus (DM). This is a large cross-sectional study, in all, 1 524 DM patients in 16 communities and villages of Yunnan Province who were registered in health service centers were included in this study from August to November 2019. All patients completed a uniform questionnaire, anthropometric measurements, biochemical measurements, and auxiliary examinations. Logistic regression analysis was used to screen the risk factors of DR. The prevalence rates of DR, mild non-proliferative DR (mild-NPDR), and referable DR (RDR) were 16.0% (244/1 524), 4.5% (69/1 524), and 11.5% (175/1 524), respectively. Glycated hemoglobin A 1c (HbA 1c)≥7.0% was the risk factor of mild-NPDR ( OR=1.872, 95% CI 1.055-3.323) and RDR ( OR=4.821, 95% CI 2.917-7.969). Blood pressure≥130/80 mmHg (1 mmHg=0.133 kPa) was the risk factor of mild-NPDR ( OR=1.933, 95% CI 1.112-3.358) and RDR ( OR=1.505, 95% CI 1.063-2.130). In Yunnan Province, 16.0% DM patients had accompanying DR, wherein about 71.7% of them required an ophthalmology referral, and the high incidence of RDR in DM patients was associated with poor control of blood glucose and blood pressure.

Chinese Medical Association and L'Oréal Group jointly launched the "China Skin & Hair Grant" from 2003 to 2018 to support Chinese dermatologists in skin and hair research. This program has not only helped improve the research capability of Chinese dermatologists, but also yielded abundant valuable Chinese population-based clinical and basic research results, and further enabled active academic communication through Chinese and international journals and conferences. This article summarizes main results from skin-related research projects based on program records and publications.