Objective: To investigate the current status and relationship between loneliness and negative emotional symptoms among first generation college students in the family, so as to provide reference for improving mental health of this population. Methods: A convenience sampling method was used to select 3 017 college students from 10 colleges and universities in Guangdong Province and Yunnan Province, China, in May 2023. Questionnaires were administered to the students, and the Depression Anxiety Stress Scale (DASS-21) and the short form of the University of California at Los Angeles Loneliness Scale (ULS-6) were employed. Results: The total ULS-6 score of first generation college students in the family was (12.38±4.16), while the score of non first generation college students in the family was (11.89±4.38), with a statistically significant difference ( t=2.79, P <0.05). The total DASS-21 score of first generation college students in the family was (71.13±26.97), while the score of non first generation college students in the family was (70.20±26.66), with a statistically significant difference ( t=2.69, P <0.05). Among the first generation college students in the family, male students experienced more DASS-21 score (77.55±29.36) than female students (70.43±25.03)( t =5.79, P <0.05). Urban students (12.00±4.15, 70.34±25.68) reported lower levels of loneliness score and DASS- 21 score than rural students (12.62±4.15, 74.93±27.63), and the depression subscale scores showed statistically significant differences among students with different professional achievement rankings ( t/F =-3.42, -3.94, 4.25, P <0.05). There was a positive correlation between loneliness, depression, anxiety, pressure and DASS-21 scales of first generation college students in the family ( r=0.64, 0.62, 0.64, 0.66, P <0.01). The linear regression analysis results showed a positive correlation between loneliness and all dimensions and total scores of the DASS-21, explaining 44% of the variance in negative emotional symptoms. Conclusions A positive correlation is found between loneliness and negative emotional symptoms among first generation college students in the family. Improving the loneliness of the first generation college students in the family can reduce their negative emotional symptoms and improve their mental health level.

OBJECTIVE: To investigate the persistent damage of learning and memory ability after the cessation of sub-chronic manganese(Mn)-exposure in rats. METHODS: Specific pathogen free weaning male SD rats were randomly divided into control group and low-, medium-and high-dose groups based on body weight, with 6 rats in each group. Rats were intraperitoneally injected with Mn chloride(MnCl_2·4 H_2O) at the concentrations of 0, 5, 10, or 20 mg/kg body weight, 5 days per week for 6 weeks and continued to be observed for 12 weeks after the cessation of Mn-exposure. During the experiment, the body mass of the rats was weighed. Learning and memory ability was evaluated by a Morris water-maze task at the 6 th weeks of Mn-exposure(cessation of Mn-exposure of week 0), the 6 th and 12 th week of the cessation of Mn-exposure. The organ coefficients of heart, liver, spleen, kidney and testicles were evaluated after the cessation of Mn-exposure on week 12. RESULTS: The body mass of the high-dose group was lower than that of the other 3 groups(P<0.05) at the 4 th and 6 th week of Mn-exposure and the 2 nd week of the cessation of Mn-exposure. There was no significant difference in body mass between the groups(P>0.05) on the 12 th week of the cessation of Mn-exposure. The escape latency of high-dose group was higher than that of the control group(P<0.05), and the number of platform crossings in the low-, medium-and high-dose groups were fewer than that in the control group(P<0.05) after the cessation of Mn-exposure. The escape latency was shorter and the numbers of platform crossings were higher on the 6 th and 12 th week of the cessation of Mn-exposure(P<0.05) when compared with that of the 6 th week of Mn-exposure rats. There was no statistical significance in the organ coefficients of heart, liver, spleen, kidney and testicles among the 4 groups at the 12 th week of the cessation of Mn-exposure in rats(P>0.05).CONCLUSION: Sub-chronic Mn exposure can impair learning and memory ability of rats, and the damage persists after the cessation of Mn-exposure.

Objective To understand the infection situation of human T lymphocyte virus(HTLV) among blood donors in Zhongshan area.Methods Blood samples from 40 874 blood donors in Zhongshan from March to December 2016 were screened for HTLV antibody by using,enzyme linked immunosorbent assay(ELISA).The positive samples were reexamined two times,and specimens with positive results of reexamination were detected by using immunohistochemical method(CLIA).Then the positive samples were confirmed by Western blot(WB),and confirmed positive samples were judged as infection.Results Of all 40 874 cases of voluntary blood donors,21 cases were positive with HTLV antibody detected by ELISA,the positive rate of ELISA was 0.05%.Five cases were positive detected by CLIA method.One case was confirmed by WB,and the infection rate was 0.002 4%.Conclusion In order to ensure the safety of blood transfusion and reduce blood transfusion infection of HTLV,it might be necessary to perform HTLV screening in first-time blood donors in Zhongshan area.

Objective To explore the MR imaging characteristics of brain tumors in infants to improve the diagnosis and early treatment.Methods Twelve infants with brain tumors (less than 1 year old),performed surgery in our hospital from April 2008 to August 2014 and proved by pathology,were collected in our study; the clinical data and MR imaging features were reviewed retrospectively.Results Among the 12 infants,4 (33％) had tumors located at the lateral ventricle,3 (25％) at the cerebral hemisphere,one (8.3％) at the pineal region,one (8.3％) at the suprasellar region,one (8.3％) at the cerebral convexity,one (8.3％) at the cerebellar hemisphere and one (8.3％) at the fourth ventricle.These tumors included immature teratoma (n=3),choroid plexus tumor (n=3),atypical teratoid/rhabdoid tumor (n=2),medulloblastoma (n=1),anaplastic ependymoma (n=1),pilomyxoidastrocytomas (n=1) and infantile fibrosarcoma (n=1).Diversity of MR imaging features was found in different types of brain tumors; tumors as immature teratoma,atypical teratoid/rhabdoid tumor and infantile fibrosarcoma showed mainly mixed signal intensity on T1-weighted images and T2-weighted images,and these tumors displayed heterogeneously enhancement at MR imaging; choroid plexus tumors and medulloblastoma showed isointenseon T1-weighted images and T2-weighted images mostly,and both had obvious enhancement; anaplastic ependymoma showed isointensity signal on T1-weighted images,slightly hyperintenseon T2-weighted images and heterogeneously enhancement; pilomyxoidastrocytomas were hypointenseon Tl-weighted images,hyperintenseon T2-weighted images and homogeneous enhancement.Conclusions Immature teratomas,choroid plexus tumors and embryonal tumors are common in infants.Supratentorial tumors are mostly found.Typical features are showed in some brian tumors,but part of atypical tumors remain challenging in diagnosis.To improve diagnostic accuracy,imaging data should be accumulated in the future.

Objective To investigate the cognitive-communication ability of people aged 20-30 years in China. Methods 139 normal participants took part in the Cookie Theft test. 8 different indexes were used to analyze the language samples. These indexes were total words number, the percentage of incorrect statement, dysfluencies, providing structure support, repetition, content units, elaborations of content units and irrelevancies. Results The rater consistence reliability was 1, 0.89, 0.85, 0.93, 0.92, 0.98, 0.98, 0.62, respectively. Conclusion The norms have acceptable reliability.

A novel method for the detection of moroxydine ( ABOB) residue in tomatoes was developed based on the enhancement of the fluorescence intensity of CdTe quantum dots( QDs) in the presence of ABOB. The factors influencing the performance of the QDs fluorescent probes were investigated, and the optimum conditions were determined:the concentration of mercaptoacidic acid ( TGA) capped-CdTe quantum dot was 1×10-4 mol/L, and the reaction time was 20 min at pH=5. 6. Under the optimum conditions, the relative fluorescence intensity increases linearly proportional to the ABOB concentration in the range of 1. 0×10-12-5. 0×10-10 mol/L with a limit of detection of 5. 2×10-13 mol/L, R=0. 9981, the recovery was 97%-106%, without obvious interference on the determinations of moroxydine from the common coexisting ions, antibiotics, and vitamins. The proposed method has been successfully applied in the detection of trace moroxydine hydrochloride residue in tomatoes.

Objective: To investigate the expression and prognostic significance of insulin-like growth factor binding protein 5 (IGFBP5) in gastric adenocarcinoma (GAC). Methods:IGFBP5 expression in tissue samples from 236 GAC patients was analyzed us-ing immunohistochemical methods. These patients had undergone surgical resection between 20003 and 2006 in Sun Yat-Sen Universi-ty Cancer Center. The relationship between IGFBP5 expression and clinicopathological factors in the 236 GAC patients was analyzed using Pearson correlation analysis. The significance of IGFBP5 in predicting the survival status of these patients was analyzed using Ka-plan-Meier survival analysis and Cox's proportional hazards regression model. Results:Immunohistochemical staining data indicated that IGFBP5 expression was significantly decreased in 159 of the total GAC cases (67.4%). Of the 62 cases with well-and moderately differentiated GAC, 31 (50%) exhibited reduced IGFBP5 expression. Of the 174 cases with poorly differentiated GAC, 128 showed re-duced IGFBP5 expression. Reduced IGFBP5 expression was also observed in female patients and in patients with tumors over 5 cm in size or with poorly differentiated tumors (P<0.05). The reduced expression of IGFBP5 was common in the tumors that were staged as T3+4a/b andⅢ/Ⅳ(P<0.05). Kaplan-Meier survival analysis revealed that the reduced expression of IGFBP5 was associated with poor prognosis in GAC patients (P<0.001). Cox regression analysis identified IGFBP5 expression as an independent prognostic factor for the overall survival of these cancer patients (HR=1.897, P=0.029). Conclusion: IGFBP5 expression is reduced in GAC tissues, and IGFBP5 independently predicts an unfavorable prognosis in GAC patients.

Escherichia coli (E. coli) FadR regulator plays dual roles in fatty acid metabolism, which not only represses the fatty acid degradation (fad) system, but also activates the unsaturated fatty acid synthesis pathway. Earlier structural and biochemical studies of FadR protein have provided insights into interplay between FadR protein with its DNA target and/or ligand, while the missing knowledge gap (esp. residues with indirect roles in DNA binding) remains unclear. Here we report this case through deep mapping of old E. coli fadR mutants accumulated. Molecular dissection of E. coli K113 strain, a fadR mutant that can grow on decanoic acid (C10) as sole carbon sources unexpectedly revealed a single point mutation of T178G in fadR locus (W60G in FadRk113). We also observed that a single genetically-recessive mutation of W60G in FadR regulatory protein can lead to loss of its DNA-binding activity, and thereby impair all the regulatory roles in fatty acid metabolisms. Structural analyses of FadR protein indicated that the hydrophobic interaction amongst the three amino acids (W60, F74 and W75) is critical for its DNA-binding ability by maintaining the configuration of its neighboring two β-sheets. Further site-directed mutagenesis analyses demonstrated that the FadR mutants (F74G and/or W75G) do not exhibit the detected DNA-binding activity, validating above structural reasoning.
3-Oxoacyl-(Acyl-Carrier-Protein) Synthase ; genetics ; metabolism ; Amino Acid Sequence ; Bacterial Proteins ; chemistry ; genetics ; metabolism ; DNA, Bacterial ; chemistry ; metabolism ; Escherichia coli ; genetics ; metabolism ; Escherichia coli Proteins ; genetics ; metabolism ; Fatty Acid Synthase, Type II ; genetics ; metabolism ; Fatty Acids ; metabolism ; Gene Expression Regulation, Bacterial ; Hydro-Lyases ; genetics ; metabolism ; Hydrophobic and Hydrophilic Interactions ; Lipid Metabolism ; Models, Molecular ; Molecular Sequence Data ; Mutation ; Protein Binding ; Protein Structure, Secondary ; Repressor Proteins ; chemistry ; genetics ; metabolism ; Sequence Alignment ; Sequence Homology, Amino Acid ; Signal Transduction

Objective To construct the Chinese Semantic Battery and evaluate the significance of clinical application. Methods 45 normal subjects and 100 patients with brain damage finished the Chinese Semantic Battery, including Oral Picture Naming, Picture Pyramids and Palm Trees Test, Word Pyramids and Palm Trees Test, Word Picture Verification and Word Reading. The scores of normal subjects were as norms, and the sensibility, specificity, and Youden's index of the patients were calculated. Results The sensitivity of the battery was 0.96,and the sensitivity of each task was 0.78, 0.68, 0.66, 0.72 and 0.64, respectively. The specificity was 0.96, 0.96, 0.98, 0.96 and 1.00, respectively.Youden's index was 0.60, 0.46, 0.42, 0.39 and 0.50, respectively. Conclusion The validity of norms of Chinese Semantic Battery is acceptable for semantic impairments and can be applied to clinical diagnoses and scientific researches.