Objective To control the stepwise release of vascular endothelial growth factor A(VEGF-A)within the microcapsules,and to analyze the effects of the microcapsules on cellular angiogenic capability.Methods VEGF-A encapsulated poly(lactic-co-gly-colic acid)(PLGA)microcapsules were prepared using a method combining dual-channel coaxial injection and continuous flow technol-ogy.The release and degradation performance of the microcapsules were characterized using a phosphate-buffered saline(PBS)soaking method.The biocompatibility of the microcapsules was assessed through the CCK-8 method and Calcein-AM/PI staining method.The impact of microcapsule extract on cellular angiogenesis ability was examined by conducting cell scratch assays and tubule formation ex-periments.Results The microcapsules were round in shape,with their particle diameter measuring in the range of hundreds of mi-crometers.Microcapsules with a molecular weight(Mw)-12 ku can release a large amount of VEGF-A in the initial phase,while Mw-30 ku ones had the capacity to provide a stable,long-term,low-dose release of VEGF-A.Microcapsules of Mw-12 ku exhibited outstanding potential for enhancing the healing of cell scratch wounds in the initial phase.Moreover,within the 0-12 day period,the two types of microcapsule extracts significantly enhanced the ability of cells to form tubules in vitro.Conclusion This study successfully regulated the release profile of VEGF-A by adjusting the molecular weight of PLGA,achieving an initial rapid and substantial release of VEGF-A followed by a sustained slow release over time,while maintaining its biological activity throughout the process.

Thyrotoxic periodic paralysis(TPP) is a rare but potentially life-threatening complication of thyrotoxicosis. TPP secondary to thyrotoxicosis factitia(TF) is exceptionally uncommon. Here, we report the case of a 31-year-old female who developed TF and subsequent TPP after taking laxatives containing unknown ingredients. The patient presented with acute onset of quadriplegia. Laboratory investigations revealed severe hypokalemia(serum potassium 1.47mmol/L), thyrotoxicosis[thyroid stimulating hormone(TSH)<0.005 mIU/L, free thyroxine(FT 4) 30.84 pmol/L, free triiodothyronine(FT 3) 7.71 pmol/L], and a decreased thyroglobulin level(3.08 ng/mL). The patient′s symptoms resolved rapidly following potassium supplementation, and thyroid function gradually normalized after discontinuation of the suspected medication. This case highlights the importance of considering TF in the differential diagnosis of TPP, particularly in patients with a history of unknown medication use. It also underscores the diagnostic value of thyroglobulin measurement in identifying TF and outlines clinical strategies for the management of TF-induced TPP.

Objective To control the stepwise release of vascular endothelial growth factor A(VEGF-A)within the microcapsules,and to analyze the effects of the microcapsules on cellular angiogenic capability.Methods VEGF-A encapsulated poly(lactic-co-gly-colic acid)(PLGA)microcapsules were prepared using a method combining dual-channel coaxial injection and continuous flow technol-ogy.The release and degradation performance of the microcapsules were characterized using a phosphate-buffered saline(PBS)soaking method.The biocompatibility of the microcapsules was assessed through the CCK-8 method and Calcein-AM/PI staining method.The impact of microcapsule extract on cellular angiogenesis ability was examined by conducting cell scratch assays and tubule formation ex-periments.Results The microcapsules were round in shape,with their particle diameter measuring in the range of hundreds of mi-crometers.Microcapsules with a molecular weight(Mw)-12 ku can release a large amount of VEGF-A in the initial phase,while Mw-30 ku ones had the capacity to provide a stable,long-term,low-dose release of VEGF-A.Microcapsules of Mw-12 ku exhibited outstanding potential for enhancing the healing of cell scratch wounds in the initial phase.Moreover,within the 0-12 day period,the two types of microcapsule extracts significantly enhanced the ability of cells to form tubules in vitro.Conclusion This study successfully regulated the release profile of VEGF-A by adjusting the molecular weight of PLGA,achieving an initial rapid and substantial release of VEGF-A followed by a sustained slow release over time,while maintaining its biological activity throughout the process.

Thyrotoxic periodic paralysis(TPP) is a rare but potentially life-threatening complication of thyrotoxicosis. TPP secondary to thyrotoxicosis factitia(TF) is exceptionally uncommon. Here, we report the case of a 31-year-old female who developed TF and subsequent TPP after taking laxatives containing unknown ingredients. The patient presented with acute onset of quadriplegia. Laboratory investigations revealed severe hypokalemia(serum potassium 1.47mmol/L), thyrotoxicosis[thyroid stimulating hormone(TSH)<0.005 mIU/L, free thyroxine(FT 4) 30.84 pmol/L, free triiodothyronine(FT 3) 7.71 pmol/L], and a decreased thyroglobulin level(3.08 ng/mL). The patient′s symptoms resolved rapidly following potassium supplementation, and thyroid function gradually normalized after discontinuation of the suspected medication. This case highlights the importance of considering TF in the differential diagnosis of TPP, particularly in patients with a history of unknown medication use. It also underscores the diagnostic value of thyroglobulin measurement in identifying TF and outlines clinical strategies for the management of TF-induced TPP.

Objective To analyze the effect of night-shift work, anxiety and their interaction on work-related musculoskeletal disorders (WMSDs) among electronics manufacturing employees. Methods A total of 2 676 employees from 58 electronic manufacturing enterprises in the Pearl River Delta region of Guangdong Province were selected as the research subjects using the judgment sampling method. The Basic Situation Survey Scale, Generalized Anxiety Disorder 7-item Scale and Questionnaire of Musculoskeletal Disorders were used to assess night-shift work, anxiety and the prevalence of WMSDs in employees. The multivariate logistic regression model was used to analyze the effects of night-shift work, anxiety and their combined effects on the risk of WMSDs. Results The proportion of night-shift work was 30.3%, and the detection rates of anxiety and WMSDs were 26.8% and 41.3%, respectively. The results of multivariate logistic regression analysis showed that night-shift work and anxiety were independent risk factors of WMSDs in the research subjects, after excluding the influence of confounding factors such as age, marital status, enterprise size and length of service [odds ratio (OR) and 95% confidence interval (CI) were 1.307 (1.092-1.564) and 3.282 (2.739-3.934), respectively, both P<0.01]. Compared with those without night-shift work or anxiety, the risk of WMSDs was higher in individuals with only night-shift work, only anxiety, or both night-shift work and anxiety [OR and 95%CI were 1.347 (1.091-1.663), 3.395 (2.727-4.227) and 4.117 (3.072-5.519), respectively, all P<0.01]. Conclusion Both night-shift work and anxiety can increase the risk of WMSDs among electronic manufacturing employees, and these two factors exhibit a synergistic effect in increasing the risk of WMSDs.

Objective This study aimed to explore the effects of bone morphogenetic protein 2(BMP-2)encapsula-ted in poly(lactic-co-glycolic acid)(PLGA)microcap-sules with different molecular weights on the osteogenic ability of osteoblasts.Methods PLGA microcapsules with different molecular weights(12 000,30 000)encap-sulating BMP-2,were prepared using a dual-channel mi-croinjection pump.The morphology and structure of the microcapsules were characterized by optical microscopy and scanning electron microscopy.The sustained-release performance of the microcapsules was characterized by phosphate buffered saline immersion method.The cell compatibility of the microcapsules was detected by the Calcein-AM/PI stain-ing and CCK-8 method.The chemotactic effect of BMP-2-encapsulated microcapsules on MC3T3-E1 cells after 48 h of treatment was detected by the Transwell assay.The alkaline phosphatase activity assay and Alizarin Red S staining were used to characterize the effect of microcapsules on the osteogenic ability of MC3T3-E1 cells.Results Both types of mi-crocapsules with different molecular weights exhibited smooth surfaces,as well as uniform and good cell compatibility.The chemotactic effect of the 12 000 microcapsules was outstanding.The 30 000 microcapsules had a longer sustained-release time,and the initial burst release was reduced by approximately 25%compared with the 12 000 microcapsules.In addition,30 000 microcapsules performed better in long-term osteogenesis induction than 12 000 microcapsules.Conclu-sion In this study,the release of BMP-2 is regulated by adjusting the molecular weight of PLGA,and the results indi-cate that 30 000 microcapsules can better induce the long-term osteogenic ability of MC3T3-E1 cells.

Objective:To explore the epidemiological characteristics of Streptococcus pyogenes, namely β-hemolytic Group A Streptococcus (GAS) in children in Shenzhen. Methods:Multilocus sequence typing (MLST) data on the epidemic clonal population of GAS infection in children in Shenzhen Children′s Hospital from January 2016 to December 2018 were retrospectively analyzed.In the present study, 32 GAS strains belonging to 7 different emm types were from 32 children′s with impetigo, cellulitis, scarlet fever, sepsis, pneumonia, obstructive sleep apnea hypopnea syndrome, bronchitis, allergy with rhinitis, buttock abscess, allergic purpura or pharyngeal tonsillitis, which were isolated from 23 throat swabs, 5 sputum samples, 3 pus and 1 blood.Using polymerase chain reaction technology, 7 pairs of allelic housekeeping genes ( gki, gtr, murI, mutS, recP, xpt and yqiL) of 32 GAS isolates were analyzed, and the target gene products were subjected to sequencing.Then the obtained gene sequences of each allele were submitted to the MLST database to obtain the allele profile.Finally, the allele profiles were introduced in the MLST database again to confirm the sequence typing (ST). Results:The GAS clone groups of emm 1.00 and its subtypes, emm 4.00, emm 12.00 and its subtypes, emm 22.00, emm 28.00, emm 75.00, and emm 89.00 belonged to the sequence typing ST28, ST39, ST36, ST46, ST52, ST49, and ST921, respectively. Conclusions:From 2016 to 2018, the MLST clone populations of GAS isolates causing infections in children in Shenzhen are classified as ST28, ST39, ST36, ST46, ST52, ST49 and ST921.

Objective To investigate the effects of hospital-community-familycontinuing nursing on the breastfeeding self-efficacy and role adaptation ability of primiparae.Methods One hundred and thirty eight postpartum women were recruited and randomly divided into the intervention group (n=69) and the control group (n=69). All patients received conventional continuing nursing, and patients in the intervention group also received hospital-community-family continuing nursing intervention. The maternal self-efficacy and role adapta-tion ability of patients between two groups before and after intervention were evaluated.Results After nursing intervention, the scores of breastfeeding self-efficacy (62.52±8.39) in the intervention group which were higher than that in the control group (45.18±8.27) (t=12.23,P<0.01). The scores of role adaptation in the intervention group was higher than the control group (t=10.04,P<0.01).Conclusions The hospital-community-family continuing nursing intervention mode can effectively improve the breastfeeding behavior of primiparae, and improve the success rate of breastfeeding.

Objective To compare the disinfection efficacy of different disinfectants on dental unit waterlines (DUWLs). Methods 18 sets of DUWLs were randomly divided into 4 groups,and disinfected or treated with hydrogen peroxide (H2 O2 )disinfectant,sodium hypochlorite (NaClO)disinfectant,hydrogen peroxide silver ion disinfectant(Sanosil),and distilled water (DW)respectively.Water specimens from triple syringes and high-speed handpieces were taken,bacterial count before and after disinfection were compared.Results Before disinfection,no significant differences in bacterial counts were found among four groups (all P >0.05),bacterial counts of DUWLs of all groups severely exceeded the standard(all>3 000 CFU/mL).After disinfection,except DW group,bacterial counts of DUWLs of the other groups declined dramat-ically (all <100 CFU/mL),bacterial count after disinfection were all obviously lower than before disinfection (all P <0.001 ).One week after disinfection,bacterial counts among three disinfectant groups in different time periods were statisti-cally different (triple syringes:Day1—Day5,all P <0.05;high-speed handpieces:Day2,Day3 and Day5,all P <0.05). Day3 after disinfection of triple syringes by H2 O2 and NaClO,Day4 after disinfection of high-speed handpieces by H2 O2 and NaClO,and Day5 of triple syringes and high-speed handpieces by Sanosil all exceeded the standard of Center for Disease Control and Prevention of America.One week after disinfection,bacterial counts of three disinfection groups all exceeded or approximated to that before disinfection.Conclusion Three types of disinfectants can all effectively reduce bacterial load in DUWLs.Compared with other disinfectants,Sanosil has advantage of inhibiting bacterial growth after disinfection.

Objective To explore the influence of the health belief model education on the life quality of nurses.Methods 200 nurses were randomly divided into the experimental group and the control group with 100 cases in each,the experimental group received health belief model education while the control group was given no intervention.The life quality of nurses before and after the education was compared.Results The life guality of nurses showed no significant difference between the two groups before the health belief model education,one month after health belief model education,life quality of nurses in the two groups showed significant difference.Conclusions Application of the health belief model education can improve the nurses'quality of life.