Causal link between gut microbiota and osteoporosis analyzed via Mendelian randomization.

OBJECTIVE: Osteoporosis (OP) is closely associated with gut microbiota (GM), yet the nature of their causal relationship remains elusive. Therefore, this study aims to reverse causality between GM and OP by using population cohorts and two-sample MR (TSMR) analysis. MATERIALS AND METHODS: In this study, we conducted an extensive genome-wide association study (GWAS) using publicly accessible summary statistics data for GM and OP. Employing rigorous criteria (p < 1*e-5), we identified independent genetic loci that exhibited significant associations with GM relative abundances as instrumental variables (IVs). A causal evaluation was primarily carried out using the inverse variance-weighted (IVW) method, supplemented by additional analyses such as MR-Egger, weighted median, simple mode, and weighted mode. RESULTS: We unveiled that increased abundances of the family Pasteurellaceae, order Pasteurellales, and genus Ruminococcaceae UCG004 were linked to an increased risk of OP. Conversely, the family Oxalobacteraceae, unknown family id.1000006161, genus Lachnospiraceae NK4A136 group, unknown genus id.1000006162, and order NB1n were associated with a reduced risk of OP. To ensure the reliability of our findings, we conducted quality assessments through Cochrane's Q test and a leave-one-out analysis. Furthermore, the stability and consistency of the results were confirmed by the MR-Egger intercept test, Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) global test, and sensitivity analysis (p > 0.05). Our study reveals the causal relationships between 211 GM taxa and OP, pinpointing specific GM taxa associated with the risk of OP. This research sheds light on the genetic mechanisms that underlie GM-mediated OP and opens up promising avenues for identifying valuable biomarkers and potential therapeutic targets in future OP research. CONCLUSIONS: This study establishes a substantial GM-OP link with specific taxa being identified, offering biomarkers for early detection, tailored interventions, and improved patient education. These findings enhance OP diagnosis, prevention, and treatment, promising more effective, individualized care and inspiring future research.

Development and validation of a novel craniofacial statistical shape model for the virtual reconstruction of bilateral maxillary defects.

Bilateral maxillary defects are a challenge for fibula free flap reconstruction (FFFR) surgery due to limitations in virtual surgical planning (VSP) workflows. While meshes of unilateral defects can be mirrored to virtually reconstruct missing anatomy, Brown class c and d defects lack a contralateral reference and associated anatomical landmarks. This often results in poor placement of osteotomized fibula segments. This study was performed to improve the VSP workflow for FFFR using statistical shape modeling (SSM) - a form of unsupervised machine learning - to virtually reconstruct premorbid anatomy in an automated, reproducible, and patient-specific manner. A training set of 112 computed tomography scans was sourced from an imaging database by stratified random sampling. The craniofacial skeletons were segmented, aligned, and processed via principal component analysis. Reconstruction performance was validated on a set of 45 unseen skulls containing various digitally generated defects (Brown class IIa-d). Validation metrics demonstrated promising accuracy: mean 95th percentile Hausdorff distance of 5.47 ± 2.39 mm, mean volumetric Dice coefficient of 48.8 ± 14.5%, compactness of 7.28 × 105 mm2, specificity of 1.18 mm, and generality of 8.12 × 10-6 mm. SSM-guided VSP will allow surgeons to create patient-centric treatment plans, increasing FFFR accuracy, reducing complications, and improving postoperative outcomes.

Lung cancer screening study from a smoking population in Kunming.

OBJECTIVE: Yunnan, China, is a central tobacco-producing region with a large smoking population and an increasing incidence of lung cancer in recent years. This study aimed to understand the incidence of lung cancer and the characteristics of lung nodules on low-dose computed tomography (LDCT) scans of the chest in a long-term smoking population in Kunming. PATIENTS AND METHODS: Long-term smokers in Kunming who were not at risk of evident lung disease symptoms were recruited through recommendation and publicity by the Kunming University of Science and Technology. RESULTS: Among 375 cases eligible for inclusion,14 cases of lung cancer were detected with a detection rate of 3.73% (95% CI: 2.55%-4.27%), including one case of squamous carcinoma, one case of small cell lung cancer, seven cases of adenocarcinoma of the lung and five cases of early-stage lung cancer (35.71%). In the group of < 6 mm solid nodules and < 5 mm non-solid nodules, no lung cancer was detected in 201 cases; lung cancer was detected in 14 cases in 61 cases, and there was a statistical difference between the two groups (p < 0.05). CONCLUSIONS: The lung cancer detection rate in long-term smokers was high, with the type predominantly adenocarcinoma and a high incidence of lung nodules, and increased when solid nodules≥6 mm or non-solid nodules ≥ 5 mm were present. It is recommended that screening for lung cancer by LDCT of the chest be introduced in the male smoking population who meet the risk factors and that screening for lung cancer in women should be redefined as a high-risk factor.

Remdesivir as a broad-spectrum antiviral drug against COVID-19.

OBJECTIVE: List the clinical data of the role of remdesivir in COVID-19, and try to make an objective evaluation and analyze its feasibility. MATERIALS AND METHODS: The keywords of "remdesivir", "COVID-19" and "SARS-CoV-2" were systematically searched in PubMed and Web of Science. After removing the repetitions, we summarize articles, letters, and comments on remdesivir in the treatment of COVID-19. RESULTS: In this review, we summarize clinical case of using remdesivir in the treatment of COVID-19, analyzed the final treatment results, and judged whether the drug was effective for the treatment of COVID-19. Also, attention was paid to the side effects of the drug. CONCLUSIONS: According to the clinical results, it was found that remdesivir was effective in the treatment of COVID-19. The drug has side effects, but the symptoms were mild and disappeared immediately after discontinuation of medication.

Cost-effectiveness analysis of capecitabine plus bevacizumab versus capecitabine alone in elderly patients with previously untreated metastatic colorectal cancer from Chinese societal perspective.

PURPOSE: The aim of the study was to evaluate the cost-effectiveness of capecitabine plus bevacizumab compared with capecitabine alone in elderly patients with metastatic colorectal cancer (CRC) from a Chinese societal perspective. METHODS: A decision-analytic Markov model was conducted to simulate the process of metastatic CRC. Three distinct health states: progression-free survival (PFS), progressive disease and death were included. Clinical data were derived from the AVEX trial. Health effectiveness was denoted in quality-adjusted life years (QALYs) and health utilities were derived from previously published studies. Incremental cost-effectiveness ratio (ICER) was regarded as the primary endpoint and willingness-to-pay (WTP) threshold was set at $26,753.37/QALY (3 × per capita GDP of China, 2017). One-way sensitivity analyses and probabilistic sensitivity analysis were also performed to explore the parameters uncertainty in the study. RESULTS: Over a 10-year life horizon, capecitabine plus bevacizumab gained 1.14 QALYs at an average cost of $21,609.48, while the effectiveness and cost of capecitabine group were 0.99 QALYs and $7274.83, respectively. The ICER between the two groups was $95,564.33/QALY. Parameters that mostly influenced the results of the model were utility of PFS state, duration of PFS state for capecitabine plus bevacizumab, total cost of PFS state for capecitabine plus bevacizumab and price of bevacizumab. The probabilities of capecitabine plus bevacizumab and capecitabine as the dominant option were 0% and 100% at the WTP threshold of $26,753.37/QALY. CONCLUSIONS: The results of the study showed that capecitabine plus bevacizumab is unlikely to be a cost-effective treatment option for elderly patients with metastatic CRC.

CXCR4 antagonist AMD3100 enhances the response of MDA-MB-231 triple-negative breast cancer cells to ionizing radiation.

Radiation therapy (RT) is one of the primary modalities for triple-negative breast cancer (TNBC) treatment. However, due to the pro-metastatic potential of radiation and the intrinsic radiation resistance of some tumors, many patients experience RT failure, which leads to cancer relapse and distant metastasis. This preclinical study evaluated the efficacy of the antagonist of the SDF-1 receptor CXCR4, AMD3100, as a radiosensitizer in TNBC models. The combined effect of ionizing radiation and AMD3100 was determined in vitro by surviving fraction, cell cycle distribution, Bax and Bcl-2 expression, and apoptosis assays in a TNBC cell line (MDA-MB-231). For in vivo studies, human xenograft athymic nude mice were used. Treatment of TNBC cells with AMD3100 significantly augmented cellular radiosensitivity. Radiosensitivity was enhanced specifically through increased Bax expression, reduced Bcl-2 expression, prolonged G2-M arrest, and increased apoptosis. Combined treatment with AMD3100 and irradiation also enhanced tumor growth delay, with an enhancement factor ranging from 1.5 to 1.8. These findings support the evaluation of antagonists of the SDF-1 receptor CXCR4, such as AMD3100, as potent radiosensitizers in TNBC.

[A Study on the establishment of immune thrombocytopenia model induced by anti-platelet GPâ bα antibodies].

Objective: To establish primary immune thrombocytopenia (ITP) animal model induced by anti-platelet membrane glycoprotein GPⅠbα antibodies AN51 and R300. Methods: Twenty guinea pigs (6-8 week) were divided into 4 groups. Five guinea pigs in each group were intravenously injected with different doses of AN51 (0.05, 0.1, 0.2 µg/g) and 0.2 µg/g IgG as control. The whole blood was collected from inner angular venous plexus. Platelets number was determined by an automated cell counter and Swiss-Jim method. Then, the similar protocol was used to establish ITP nude mice model by intraperitoneal injection of different concentrations of anti-platelet GPⅠbα antibody R300, respectively. Results: ①Five minutes after intravenous injection of AN51 at 0.05, 0.1 and 0.2 µg/g, the platelet counts of guinea pigs reduced about 0-5%, 50%-60% and 70%-80% compared to the control group, respectively. The difference was statistically significant (P<0.01) . ②Six hours after intraperitoneal injection of R300 at 0.05, 0.1, 0.2 µg/g, the platelet counts of nude mice decreased about 20%-30%, 60%-70% and 80%-90% compared to the control group, respectively. The difference was statistically significant (P<0.01) . The nude mice, injected 0.2 µg/g R300 once a day for 2 weeks, showed typical ITP clinical manifestations including large number of petechiaes or ecchymoses on limbs, head and abdomen. Conclusion: AN51 at 0.2 µg/g and R300 at 0.2 µg/g could establish stable ITP model in guinea pigs and nude mice respectively.

[Effects of metalloproteinases-1 (TIMP-1) cDNA transfection on biological behaviors of PG cells].

A recombinant plasmid, which contains a full length cDNA of human tissue inhibitor of metalloproteinases-1 (TIMP-1), was constructed by using gene recombinant technique, and introduced into a highly metastatic human giant cell carcinoma (PG) by lipofectin technique. Two of the transfectants, PG-T2 and PG-T4, were studied thoroughly. Northern blot showed an increased level of TIMP-1 mRNA in PG-T2 and PG-T4, compared with PG and PG-MV1 (vector-transfected control). The two transfectants also exhibited higher TIMP-1 protein activities. Moreover, they showed significant reduction in their proliferation rate and invasive abilities. The abilities of forming colonies in soft agar and tumorigenecity in athymic nude mice were abrogated in PG-T2 and PG-T4. The preliminary results suggest that a specific upregulation of TIMP-1 expression in metastatic cells could not only suppress their invasive and metastatic phenotype, but also inhibit their proliferation and tumorigenecity.

[The roles of T cells in experimental crescentic glomerulonephritis].

A crescentic glomerulonephritis (GN) model was induced by intravenous injection of rabbit anti-mouse glomerular basement membrane (GBM) antiserum and lipopolysaccharide (LPS) in BALB/c mice, heterozygous mice and nude mice respectively, in order to detect the T-cells effects on the development of crescentic GN. The immunofluorescence and morphological changes of glomeruli in different groups of animals were compared. Intense fluorescence (4+) of rabbit IgG could be found along the GBM in liner pattern in all the animals. Intense (3(+)-4+) mouse IgG was also found along the GBM in liner pattern in the normal and heterozygous mice, but could not be identified in the nude mice. The normal mice developed typical crescentic GN, characterized by serious degeneration and destruction of GBM, fibrin deposition and crescents formation, 3-6 weeks after the injection. The heterozygous mice only developed mild proliferation of the mesangial cells in the glomeruli but there was no glomerular lesion detected in the nude mice. It suggests that the glomerular immune damage requires the participation of functional T-cell.

Correlation between T cells and experimental crescentic glomerulonephritis.

A model of crescentic glomerulonephritis (GN) in mice was induced by intravenous injection of rabbit anti-mouse glomerular basement membrane (GBM) antiserum and lipopolysaccharide. The procedure was carried out in BALB/c mice, heterozygous mice and nude mice. In order to examine the role of T cells in the pathogenesis of crescentic GN, immunofluorescent and morphologic changes in the glomeruli of these animals were studied. Intense (4+) linear deposition of rabbit IgG was found along the GBM of all test animals. Intense (3(+)-4+) linear deposition of mouse IgG along the GBM was present in normal and heterozygous mice, but not in nude mice. Normal mice developed typical crescentic GN characterized by severe degeneration and destruction of GBM, fibrin deposition and crescent formation 3-6 weeks after injection. Heterozygous mice only developed mild mesangial proliferation. No glomerular lesions were seen in nude mice. These preliminary data suggest that glomerular immunologic damage requires the participation of functional T cells, and that the induction of typical crescentic GN requires integral T-cell function.