Effects of Metformin on CIMT and FMD in PCOS patients: a systematic review and meta-analysis.

BACKGROUND: This study aims to analyze the efficacy of metformin on carotid intima media thickness (CIMT) and flow-mediated dilation (FMD) for patients with polycystic ovary syndrome (PCOS). METHODS: A literature search of PubMed, Embase, and the Cochrane Library from inception to December 2023 was conducted. Then, after studies selection and data extraction, the mean difference (MD) with a 95% confidence interval (CI) was used to evaluate metformin efficacy in CIMT and FMD for PCOS patients. Heterogeneity was investigated through subgroup and sensitivity analysis. The protocol of our study has been registered in PROSPERO (CRD42024497239). RESULTS: A total of 12 studies with 248 patients were included. CIMT was lower in the endpoint group (after metformin) compared with the baseline group (before metformin) (MD = -0.11, 95% CI = -0.21 to -0.01, p = 0.04). FMD was higher in the endpoint group compared with the baseline group (MD = 3.25, 95% CI = 1.85 to 4.66, p < 0.01). No statistically significant difference was observed in nitroglycerin-mediated dilation (NMD) between the two groups (MD = 0.65, p = 0.51). Subgroup analysis showed that a relatively lower MD of CIMT in PCOS patients from Europe in the endpoint group compared with the baseline group (MD = -0.09, 95% CI = -0.14 to -0.04, p < 0.001). However, the MD in CIMT was not significantly different between the endpoint group and baseline group in PCOS patients from Asia (p = 0.270). CONCLUSION: Metformin may have a beneficial effect on CIMT and FMD, but not on NMD, suggesting that metformin may help reduce cardiovascular events in PCOS patients. Notably, the clinical efficacy of metformin can be influenced by regional differences and study types.

[Damage and changes in expression of autophagy related factors LC3 and p62 of condylar cartilage in fluorosis mouse].

PURPOSE: To study the damage and the expression of LC3 and p62 of condylar cartilage in fluorosis mouse. METHODS: Thirty 4-week-old male C57BL/6 mice were randomly divided into control group and the experimental group with 15 animals in each group. The control group received regular drinking water and the experimental group received a fluoride concentration of 75 mg/L drinking water for 8 weeks. The structure of condylar cartilage was observed through modified safranine O-fast green FCF cartilage stain kit. Immunohistochemistry was used to detect the expression of MMP-13, type Ⅱ collagen and LC3 and p62. Two-way analysis of variance test was conducted for analysis of semi-quantitative results of immunohistochemistry using SPSS 22.0 software package. RESULTS: Compared with the control group, the fibrocartilage layer of the experimental group became thinner, the condrocytes were smaller, and the staining became deeper.Immunohistochemistry results showed that the expression of MMP-13 and LC3 increased; the expression of type Ⅱ collagen and p62 decreased in the experimental group. CONCLUSIONS: There was degeneration of the condylar cartilage and autophagy in mice with drinking water containing 75 mg/L fluoride.

Mechanisms and recent advances in the diagnosis and treatment of nitrous oxide-induced peripheral neuropathy: a narrative review.

Under standard conditions, nitrous oxide (N2O) manifests as a colorless, odorless gas with a mildly sweet taste. The compound finds applications in various fields, including its use as an aerosol propellants, an accelerant in motor racing, and an anesthetic in surgical procedures and dentistry. Unfortunately, the recreational misuse of N2O has become prevalent among young individuals due to its euphoric and hallucinogenic effects. Compounding this issue is the fact that nitrous oxide can be easily obtained from over-the-counter household items, facilitating its non-medical use. The global community has witnessed a surge in the recreational utilization of nitrous oxide gas in recent years. Despite the widespread non-medical abuse of N2O, there remains inadequate understanding of the potential adverse effects resulting from exposure to it. This paper provides an overview of management findings, laboratory and electrodiagnostic characteristics, as well as clinical presentations associated with neurological disorders induced by nitrous oxide usage.

Extensor tendon rupture and preoperative mri confirmations of suture anchor prolapse: a case report and literature review.

BACKGROUND: While suture anchors are widely used in medical procedures for their advantages, they can sometimes lead to complications, including anchor prolapse. This article presents a unique case of suture anchor prolapse at the base of the distal phalanx of the little finger after extensor tendon rupture reconstruction surgery. CASE PRESENTATION: A 35-year-old male, underwent extensor tendon rupture reconstruction using a non-absorbable suture anchor. After seven years the patient visited our outpatients complaining of stiffness, pain, and protrusion at the surgical site. Initial X-ray imaging suggested suggesting either a fracture of the distal phalanx or tendon adhesion but lacked a definitive diagnosis. Subsequent magnetic resonance imaging (MRI) revealed bone connectivity between the middle and distal phalanges with irregular signal shadow and unclear boundaries while maintaining a regular finger shape. MRI proved superior in diagnosing prolapsed suture anchors, marking the first reported case of its kind. Surgical intervention confirmed MRI findings. CONCLUSIONS: Suture anchor complications, such as prolapse, are a concern in medical practice. This case underscores the significance of MRI for accurate diagnosis and the importance of tailored surgical management in addressing this uncommon complication.

An Analytical Thermal Buckling Model for Semiconductor Chips on a Substrate.

Semiconductor chips on a substrate have a wide range of applications in electronic devices. However, environmental temperature changes may cause mechanical buckling of the chips, resulting in an urgent demand to develop analytical models to study this issue with high efficiency and accuracy such that safety designs can be sought. In this paper, the thermal buckling of chips on a substrate is considered as that of plates on a Winkler elastic foundation and is studied by the symplectic superposition method (SSM) within the symplectic space-based Hamiltonian system. The solution procedure starts by converting the original problem into two subproblems, which are solved by using the separation of variables and the symplectic eigenvector expansion. Through the equivalence between the original problem and the superposition of subproblems, the final analytical thermal buckling solutions are obtained. The SSM does not require any assumptions of solution forms, which is a distinctive advantage compared with traditional analytical methods. Comprehensive numerical results by the SSM for both buckling temperatures and mode shapes are presented and are well validated through comparison with those using the finite element method. With the solutions obtained, the effects of the moduli of elastic foundations and geometric parameters on critical buckling temperatures and buckling mode shapes are investigated.

Altered miRNA expression profiling in enamel organ of fluoride affected rat embryos.

Evidence has shown that miRNAs could play a role in dental fluorosis, but there is no study has investigated the global expression miRNA profiles of fluoride-exposed enamel organ. In this study, we analysed the differentially expressed (DE) miRNAs between fluoride-treated and control enamel organ for the first time and found several candidate miRNAs and signaling pathways worthy of further research. Thirty Wistar rats were randomly distributed into three groups and exposed to drinking water with different fluoride contents for 10 weeks and during the gestation. The three groups were a control group (distilled water), medium fluoride group (75 mg/L NaF), and high fluoride group (150 mg/L NaF). On the embryonic day 19.5, the mandible was dissected for histological analysis, and the enamel organ of the mandibular first molar tooth germ was collected for miRNA sequencing (miRNA-seq) and quantitative real-time PCR analysis (qRT-PCR). Typical dental fluorosis was observed in the incisors of the prepregnant rats. In addition to the disorganized structure of enamel organ cells, 39 DE miRNAs were identified in the fluoride groups compared with the control group, and good agreement between the miRNA-seq data and qRT-PCR data was found. The functional annotation of the target genes of 39 DE miRNAs showed significant enrichment in metabolic process, cell differentiation, calcium signaling pathway, and mitogen-activated protein kinase(MAPK) signaling pathway terms. This study provides a theoretical reference for an extensive understanding of the mechanism of fluorosis and potential valuable miRNAs as therapeutic targets in fluorosis.