AIM:To investigate the function and mechanism of the smooth muscle relaxant choline theophylli-nate(CT)in activating primordial follicles in mice.METHODS:Experiments were conducted using in vitro culture of 3-day postpartum(dpp)neonatal SPF-grade female mice,intraperitoneal injection in 3-dpp neonatal mice,and oral adminis-tration in 21-dpp adolescent female mice.The mice were divided into control and CT groups.The ovaries were isolated from 3-dpp neonatal mice for the in vitro culture.Hematoxylin staining was used to count the number of primordial and growing follicles,with 10 mice in each group.qPCR was performed to analyze the expression levels of genes related to fol-licle growth,proliferation,and apoptosis,including growth differentiation factor 9(Gdf9),zona pellucida glycoprotein 3(Zp3),proliferating cell nuclear antigen(PCNA),Ki-67,B-cell lymphoma 2(BCL2),BCL2-associated X protein(BAX),and caspase-3,with 9 mice in each group.Immunofluorescence staining was used to detect the expression of pro-liferation-and apoptosis-related proteins,including PCNA,Ki-67,5-bromo-2'-deoxyuridine(BrdU),cleaved caspase-3,and forkhead box O3a(FOXO3a),with 15 mice in each group.Western blot was performed to measure the expression of DEAD-box helicase 4(DDX4),phosphorylated mammalian target of rapamycin(p-mTOR),and phosphorylated protein kinase B(p-Akt),with 9 mice in each group.Intraperitoneal injection of CT was administered to 3-dpp mice,and follicle counting was performed with 10 mice in each group.Western blotting was used to detect p-mTOR and p-Akt expression,with 9 mice in each group.Immunofluorescence was employed to assess FOXO3a nuclear export,with 15 mice in each group.For the oral administration of CT in drinking water to 21-dpp mice,immunofluorescence and hematoxylin staining was used to count follicles,with 9 mice in each group.RESULTS:Compared with control group,CT treatment signifi-cantly increased the number of growing follicles in mice.The mRNA and/or protein levels of Gdf9,Zp3,Ki-67,PCNA and DDX4 were markedly elevated.Further studies revealed that CT treatment significantly increased p-Akt levels in the ovaries but had no significant effect on p-mTOR levels.The PI3K/Akt inhibitor LY294002 also reversed the choline the-ophyllinate-induced increase in growing follicles.CONCLUSION:Choline theophyllinate promotes the activation of pri-mordial follicles in mice via the PI3K/Akt signaling pathway in oocytes.

In June 2018,sows at a pig farm in Jiamusi,Heilongjiang Province,suffered a large num-ber of miscarriages,and subsequently weaned piglets at the farm began to show persistent high fe-ver symptoms at around 35 days of age,with some pigs having a fever of more than 41.5 ℃.In or-der to determine the cause of this outbreak,63 clinical samples from this farm were tested.The re-sults showed that 60 out of 63 samples were positive for the porcine reproductive and respiratory syndrome virus(PRRSV)antigen.Subsequently,PRRSV antigen-positive plasmid was transfected into African green monkey embryonic kidney cells(Marc-145),and after three generations of blind transmission,indirect immunofluorescence assay(IFA)was performed.The results showed that one PRRSV strain,named HLJ38,was successfully isolated.Then the whole genome of HLJ38 strain was sequenced and then analyzed in detail by bioinformatics software.Sequence analysis showed that there were three deletions of 131 amino acids(323-433 aa,483 aa and 504-522 aa)in the derived sequence of Nsp2 gene of HLJ38 strain,which was consistent with the molecular ge-netic marker of NADC30 PRRSV.The phylogenetic tree analysis showed that HLJ38 and NADC30 PRRSV in GenBank belong to lineage 1 subgroup,and the nucleotide homology of HLJ38 and NADC30 PRRSV in GenBank was only 85.2％and 84.6％.Recombinant analysis showed that HLJ38 was a recombinant NADC30-like PRRSV,and the recombinant gene fragments were de-rived from multiple strains,among which the fragment of 1-201 nt was provided by VR2332 strain and fragment of 6 641-8 061 nt derived from the HP-PRRSV strain.In summary,the re-sults showed that the outbreak in this pig farm may be caused by the recombination of PRRSV strains among different lineages,and the recombinant circulating strains not only have certain pathogenicity but also suggest that the existing commercial vaccines provide limited cross-protec-tion against them.Recombination between different lineages increases the genetic diversity of PRRSV and aggravates the difficulty of prevention and control of PRRS in pig farms.Therefore,it is necessary to continuously monitor the epidemic dynamics of PRRSV in pig farms and take effec-tive measures in time to curb the spread of PRRS.

Objective:To evaluate the efficacy of reduction robot system combined with minimally invasive, microenvironmental protection, micro-stress shielding fixator (short for "3M fixator") for Sanders types II and III calcaneal fractures.Methods:A retrospective case series study was conducted to analyze the clinical data of 26 patients (26 feet) with calcaneal fractures admitted to Fourth Affiliated Central Hospital of Tianjin Medical University from June 2022 to June 2024, including 21 males and 5 females, aged 27-69 years [(46.5±2.5)years]. Among them, 10 patients had fractures in the left foot and 16 in the right. According to the Sanders classification, the fractures were classified as type II in 16 patients and type III in 10. All the patients were treated with the close reduction with reduction robot system combined with 3M fixator in a minimally invasive procedure. The surgical waiting time, operative duration, and fracture healing time were recorded. The length, width and height of the calcaneus, B?hler′s angle and Gissane′s angle were compared before operation and at 1, 3 months after operation. The visual analogue scale (VAS) and American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score before operation and at 1, 3 months after operation and at the last follow-up were detected. The postoperative complications were recorded.Results:All the patients were followed up for 6-12 months [(9.7±1.1)months]. The surgical waiting time was 1-4 days [(2.0±0.8)days]. The operative duration was 36-66 minutes [(53.2±9.5)minutes]. All the fractures achieved primary union with a healing period of 3-4 months [(3.2±0.4)months]. At 1, 3 months after operation, the length of the calcaneus [(83.3±3.7)mm and (83.6±3.6)mm], width of the calcaneus [(44.3±5.8)mm and (44.3±5.7)mm], height of the calcaneus [(50.1±3.8)mm and (50.3±3.6)mm], B?hler′s angle [(29.8±2.9)° and (29.8±3.0)°], and Gissane angle [(121.1±6.7)° and (123.9±5.9)°] were significantly improved compared with those before operation [(79.3±4.5)mm, (53.6±4.1)mm, (46.2±3.7)mm, (18.9±3.8)°, (109.0±7.5)°, respectively] ( P<0.05), with no significant differences between those indicators at 1, 3 months after operation ( P>0.05). The VAS scores were (3.2±0.6)points, (1.9±0.5)points, and (1.6±0.3)points at 1, 3 months after operation and at the last follow-up, which were lower than (7.1±0.5)points preoperatively and decreased with the prolongation of follow-up time ( P<0.05). The AOFAS scores were (73.5±6.9)points, (90.1±4.3)points, and (92.0±3.6)points, which were higher than (32.0±4.6)points preoperatively and increased with the follow-up time ( P<0.05). One patient had lateral calcaneal pain after operation, and was alleviated after rehabilitation. No complications such as infection or nonunion were found after operation. Conclusion:The reduction robot system combined with 3M fixator for Sanders types II and III calcaneal fractures demonstrates significant clinical advantages, such as reduced surgical waiting time and operative duration, promoted fracture healing, early alleviated pain, enhanced ankle joint functional recovery, and decreased complication occurrence.

Objective:To analyze differences on characteristics of HIV/AIDS knowledge, beliefs and behavior among female college students who reported having sex in Zhejiang Province between 2018 and 2020, and provide reference for HIV/AIDS prevention and control among female college students.Methods:Cross-sectional surveys were conducted in October-November 2018 and November-December 2020 among female college students in 13 universities in 11 cities in Zhejiang Province, and female college students who self-reported having sexual intercourse in the past year were included as study subjects, with sample size estimates of 5 265 and 9 466 for the two surveys, respectively. The factors related to the change of relevant characteristics of the two survey subjects were analyzed. The χ2 test was used for univariate analysis and logistic regression model was used for multivariate analysis.Statistical analyses were performed with SPSS 23.0 software. Results:Of the 17 354 and 20 675 female college students surveyed in 2018 and 2020, respectively, the proportion who self-reported having had sex in the past year was 6.56% (1 139/17 354) and 4.19% (866/20 675). Multivariate logistic regression analysis showed that compared with female college students in 2018, the students who have sexual behaviour, receiving health education class by their university in the past year (a OR=1.57, 95% CI:1.29-1.91), receiving HIV testing promotion by the university in the past year (a OR=2.59,95% CI:2.13-3.14), receiving self-assessment of HIV risk by the university in the past year (a OR=2.97,95% CI:2.43-3.65), high self-efficacyfor condom use (a OR=2.00, 95% CI:1.66-2.41), receiving voluntary counseling and HIV testing (VCT) (a OR=1.81,95% CI: 1.41-2.87), perceived risk of HIV infection (a OR=2.44, 95% CI:1.32-4.54), using condoms whenever having casual sexual behaviour in the past year (a OR=3.35,95% CI:1.66-6.77) were significantly higher in 2020. Conclusions:Compared with female college students in 2018, the proportion of female college students who self-reported sexual activity decreased slightly in 2020, and the proportion of receiving HIV/AIDS lectures or health education classes, the proportion of self-rated at risk of HIV infection, the proportion of receiving VCT, the proportion of using condoms with very high confidence in self-efficacy and condom use had an increased.

Objective:To understand the prevalence of psychoactive substance use and related factors in men who have unprotected sex with men in Zhejiang Province.Methods:Men who have unprotected sex with men were recruited by snowball sampling through men who have sex with men (MSM) social organization in Zhejiang to conduct a cross-sectional investigation from January 2022 to December 2023. The sample size was estimated to be 1 169 individuals. The information about their socio-demographic information, sexual behaviors, psychoactive substance use, and HIV testing were collected through on-site questionnaire survey. Logistic regression analysis model was used to analyze related factors about psychoactive substance use in this population.Results:A total of 1 914 men who have unprotected sex with men were included in the study, the average age of the study subjects was (31.43±10.46) years, and most of them were aged ≤35 years (70.8%, 1 356/1 914). Those with education level of high school or below accounted for 50.1% (960/1 914) and those who were not married accounted for 63.5% (1 216/1 914). Psychoactive substance use in the past 3 months was reported in 19.7% (377/1 914) of the subjects. Multivariate logistic regression analysis showed that the factors associated with psychoactive substance use in the past 3 months included age 26-35 years (a OR=1.65, 95% CI: 1.24-2.19), ≥2 sexual partners in the past 3 months (a OR=2.33, 95% CI: 1.82-2.97), STD diagnosed in the past 3 months (a OR=2.62, 95% CI: 1.45-4.74), and awareness of the HIV infection status of sexual partners (a OR=2.83, 95% CI: 2.12-3.78). Conclusions:The prevalence of psychoactive substance use in men who have unprotected sex with men was high in Zhejiang. It is necessary to strengthen the intervention in this population.

Objective:To investigate the clinical and pathological characteristics, treatment and prognosis of endometriosis (EM)-associated ovarian mesonephric-like adenocarcinoma (MLA).Methods:Clinical and pathological data were collected from nine patients diagnosed with EM-associated ovarian MLA at the Obstetrics and Gynecology Hospital of Fudan University between January 2022 and December 2024. Histological slides were re-reviewed, immunohistochemical examination and molecular testing were performed, and patient follow-up was conducted.Results:(1) Clinical characteristics: the median age of the nine patients was 54 years (range: 38-69 years). All patients presented with a pelvic mass; five cases also reported abdominal pain. Tumor location included five cases in the right ovary, two in the left ovary, and two involving both ovaries. International Federation of Gynecology and Obstetrics (FIGO) staging showed 3 cases at stage Ⅰ, 4 at stage Ⅱ, and 2 at stage Ⅲ. (2) Pathological features: gross examination revealed mixed solid-cystic masses with solid areas appearing gray-white or yellow-brown; the median maximum tumor diameter was 9.0 cm (range: 2.6-13.0 cm). Microscopically, tumors exhibited various architectural patterns, including tubular, glandular, papillary, slit-like, sex cord-like, glomeruloid, and solid structures, with tubular and glandular patterns being most common. Tumor cells demonstrated mild to moderate nuclear atypia. Of the 11 tumor foci in the 9 cases, 8 showed coexistence of MLA with other tumor components, such as endometrioid carcinoma, borderline endometrioid or borderline seromucinous tumors. In 1 case of MLA mixed with a borderline endometrioid tumor, both components exhibited squamous metaplasia. Immunohistochemistry showed variable expression of GATA-binding protein 3, thyroid transcription factor-1, CD 10, and calretinin, with positive rates of 9/11, 8/11, 5/11, and 3/6, respectively. Two tumor foci (2/11) exhibited focal expression of estrogen receptor and progesterone receptor. All cases displayed wild-type p53 expression. Molecular testing via next-generation sequencing in five patients revealed pathogenic mutations in the KRAS gene (5/5), with 3 cases (3/5) harboring additional pathogenic mutations in other genes. (3) Treatment and prognosis: all patients underwent surgery, supplemented by chemotherapy and (or) targeted therapy. Five patients underwent comprehensive staging surgery, four received cytoreductive surgery, and one patient received targeted therapy. The median follow-up duration was 7 months (range: 2-27 months). Three patients (3/9) experienced recurrence, and no deaths were reported during the follow-up period. Conclusions:EM-associated ovarian MLA demonstrates diverse morphological patterns and frequently coexists with other tumor types. Accurate diagnosis relies on an integrated evaluation of histomorphology, immunohistochemistry, and molecular testing. The primary treatment for EM-associated ovarian MLA is surgery, followed by adjuvant chemotherapy. Patients harboring pathogenic KRAS p.G12C mutations may benefit from targeted therapies. Ovarian MLA is an aggressive tumor, prone to recurrence in the short term, and has a poor prognosis.

Objective:To analyze differences on characteristics of HIV/AIDS knowledge, beliefs and behavior among female college students who reported having sex in Zhejiang Province between 2018 and 2020, and provide reference for HIV/AIDS prevention and control among female college students.Methods:Cross-sectional surveys were conducted in October-November 2018 and November-December 2020 among female college students in 13 universities in 11 cities in Zhejiang Province, and female college students who self-reported having sexual intercourse in the past year were included as study subjects, with sample size estimates of 5 265 and 9 466 for the two surveys, respectively. The factors related to the change of relevant characteristics of the two survey subjects were analyzed. The χ2 test was used for univariate analysis and logistic regression model was used for multivariate analysis.Statistical analyses were performed with SPSS 23.0 software. Results:Of the 17 354 and 20 675 female college students surveyed in 2018 and 2020, respectively, the proportion who self-reported having had sex in the past year was 6.56% (1 139/17 354) and 4.19% (866/20 675). Multivariate logistic regression analysis showed that compared with female college students in 2018, the students who have sexual behaviour, receiving health education class by their university in the past year (a OR=1.57, 95% CI:1.29-1.91), receiving HIV testing promotion by the university in the past year (a OR=2.59,95% CI:2.13-3.14), receiving self-assessment of HIV risk by the university in the past year (a OR=2.97,95% CI:2.43-3.65), high self-efficacyfor condom use (a OR=2.00, 95% CI:1.66-2.41), receiving voluntary counseling and HIV testing (VCT) (a OR=1.81,95% CI: 1.41-2.87), perceived risk of HIV infection (a OR=2.44, 95% CI:1.32-4.54), using condoms whenever having casual sexual behaviour in the past year (a OR=3.35,95% CI:1.66-6.77) were significantly higher in 2020. Conclusions:Compared with female college students in 2018, the proportion of female college students who self-reported sexual activity decreased slightly in 2020, and the proportion of receiving HIV/AIDS lectures or health education classes, the proportion of self-rated at risk of HIV infection, the proportion of receiving VCT, the proportion of using condoms with very high confidence in self-efficacy and condom use had an increased.

Objective:To understand the prevalence of psychoactive substance use and related factors in men who have unprotected sex with men in Zhejiang Province.Methods:Men who have unprotected sex with men were recruited by snowball sampling through men who have sex with men (MSM) social organization in Zhejiang to conduct a cross-sectional investigation from January 2022 to December 2023. The sample size was estimated to be 1 169 individuals. The information about their socio-demographic information, sexual behaviors, psychoactive substance use, and HIV testing were collected through on-site questionnaire survey. Logistic regression analysis model was used to analyze related factors about psychoactive substance use in this population.Results:A total of 1 914 men who have unprotected sex with men were included in the study, the average age of the study subjects was (31.43±10.46) years, and most of them were aged ≤35 years (70.8%, 1 356/1 914). Those with education level of high school or below accounted for 50.1% (960/1 914) and those who were not married accounted for 63.5% (1 216/1 914). Psychoactive substance use in the past 3 months was reported in 19.7% (377/1 914) of the subjects. Multivariate logistic regression analysis showed that the factors associated with psychoactive substance use in the past 3 months included age 26-35 years (a OR=1.65, 95% CI: 1.24-2.19), ≥2 sexual partners in the past 3 months (a OR=2.33, 95% CI: 1.82-2.97), STD diagnosed in the past 3 months (a OR=2.62, 95% CI: 1.45-4.74), and awareness of the HIV infection status of sexual partners (a OR=2.83, 95% CI: 2.12-3.78). Conclusions:The prevalence of psychoactive substance use in men who have unprotected sex with men was high in Zhejiang. It is necessary to strengthen the intervention in this population.

Objective:To investigate the clinical and pathological characteristics, treatment and prognosis of endometriosis (EM)-associated ovarian mesonephric-like adenocarcinoma (MLA).Methods:Clinical and pathological data were collected from nine patients diagnosed with EM-associated ovarian MLA at the Obstetrics and Gynecology Hospital of Fudan University between January 2022 and December 2024. Histological slides were re-reviewed, immunohistochemical examination and molecular testing were performed, and patient follow-up was conducted.Results:(1) Clinical characteristics: the median age of the nine patients was 54 years (range: 38-69 years). All patients presented with a pelvic mass; five cases also reported abdominal pain. Tumor location included five cases in the right ovary, two in the left ovary, and two involving both ovaries. International Federation of Gynecology and Obstetrics (FIGO) staging showed 3 cases at stage Ⅰ, 4 at stage Ⅱ, and 2 at stage Ⅲ. (2) Pathological features: gross examination revealed mixed solid-cystic masses with solid areas appearing gray-white or yellow-brown; the median maximum tumor diameter was 9.0 cm (range: 2.6-13.0 cm). Microscopically, tumors exhibited various architectural patterns, including tubular, glandular, papillary, slit-like, sex cord-like, glomeruloid, and solid structures, with tubular and glandular patterns being most common. Tumor cells demonstrated mild to moderate nuclear atypia. Of the 11 tumor foci in the 9 cases, 8 showed coexistence of MLA with other tumor components, such as endometrioid carcinoma, borderline endometrioid or borderline seromucinous tumors. In 1 case of MLA mixed with a borderline endometrioid tumor, both components exhibited squamous metaplasia. Immunohistochemistry showed variable expression of GATA-binding protein 3, thyroid transcription factor-1, CD 10, and calretinin, with positive rates of 9/11, 8/11, 5/11, and 3/6, respectively. Two tumor foci (2/11) exhibited focal expression of estrogen receptor and progesterone receptor. All cases displayed wild-type p53 expression. Molecular testing via next-generation sequencing in five patients revealed pathogenic mutations in the KRAS gene (5/5), with 3 cases (3/5) harboring additional pathogenic mutations in other genes. (3) Treatment and prognosis: all patients underwent surgery, supplemented by chemotherapy and (or) targeted therapy. Five patients underwent comprehensive staging surgery, four received cytoreductive surgery, and one patient received targeted therapy. The median follow-up duration was 7 months (range: 2-27 months). Three patients (3/9) experienced recurrence, and no deaths were reported during the follow-up period. Conclusions:EM-associated ovarian MLA demonstrates diverse morphological patterns and frequently coexists with other tumor types. Accurate diagnosis relies on an integrated evaluation of histomorphology, immunohistochemistry, and molecular testing. The primary treatment for EM-associated ovarian MLA is surgery, followed by adjuvant chemotherapy. Patients harboring pathogenic KRAS p.G12C mutations may benefit from targeted therapies. Ovarian MLA is an aggressive tumor, prone to recurrence in the short term, and has a poor prognosis.

In June 2018,sows at a pig farm in Jiamusi,Heilongjiang Province,suffered a large num-ber of miscarriages,and subsequently weaned piglets at the farm began to show persistent high fe-ver symptoms at around 35 days of age,with some pigs having a fever of more than 41.5 ℃.In or-der to determine the cause of this outbreak,63 clinical samples from this farm were tested.The re-sults showed that 60 out of 63 samples were positive for the porcine reproductive and respiratory syndrome virus(PRRSV)antigen.Subsequently,PRRSV antigen-positive plasmid was transfected into African green monkey embryonic kidney cells(Marc-145),and after three generations of blind transmission,indirect immunofluorescence assay(IFA)was performed.The results showed that one PRRSV strain,named HLJ38,was successfully isolated.Then the whole genome of HLJ38 strain was sequenced and then analyzed in detail by bioinformatics software.Sequence analysis showed that there were three deletions of 131 amino acids(323-433 aa,483 aa and 504-522 aa)in the derived sequence of Nsp2 gene of HLJ38 strain,which was consistent with the molecular ge-netic marker of NADC30 PRRSV.The phylogenetic tree analysis showed that HLJ38 and NADC30 PRRSV in GenBank belong to lineage 1 subgroup,and the nucleotide homology of HLJ38 and NADC30 PRRSV in GenBank was only 85.2％and 84.6％.Recombinant analysis showed that HLJ38 was a recombinant NADC30-like PRRSV,and the recombinant gene fragments were de-rived from multiple strains,among which the fragment of 1-201 nt was provided by VR2332 strain and fragment of 6 641-8 061 nt derived from the HP-PRRSV strain.In summary,the re-sults showed that the outbreak in this pig farm may be caused by the recombination of PRRSV strains among different lineages,and the recombinant circulating strains not only have certain pathogenicity but also suggest that the existing commercial vaccines provide limited cross-protec-tion against them.Recombination between different lineages increases the genetic diversity of PRRSV and aggravates the difficulty of prevention and control of PRRS in pig farms.Therefore,it is necessary to continuously monitor the epidemic dynamics of PRRSV in pig farms and take effec-tive measures in time to curb the spread of PRRS.