Inference for restricted mean survival time as a function of restriction time under length-biased sampling.

The restricted mean survival time (RMST) is often of direct interest in clinical studies involving censored survival outcomes. It describes the area under the survival curve from time zero to a specified time point. When data are subject to length-biased sampling, as is frequently encountered in observational cohort studies, existing methods cannot estimate the RMST for various restriction times through a single model. In this article, we model the RMST as a continuous function of the restriction time under the setting of length-biased sampling. Two approaches based on estimating equations are proposed to estimate the time-varying effects of covariates. Finally, we establish the asymptotic properties for the proposed estimators. Simulation studies are performed to demonstrate the finite sample performance. Two real-data examples are analyzed by our procedures.

Longitudinal metabolomics of human plasma reveal metabolic dynamics and predictive markers of antituberculosis drug-induced liver injury.

Tuberculosis (TB) remains the second leading cause of death from a single infectious agent and long-term medication could lead to antituberculosis drug-induced liver injury (ATB-DILI). We established a prospective longitudinal cohort of ATB-DILI with multiple timepoint blood sampling and used untargeted metabolomics to analyze the metabolic profiles of 107 plasma samples from healthy controls and newly diagnosed TB patients who either developed ATB-DILI within 2 months of anti-TB treatment (ATB-DILI subjects) or completed their treatment without any adverse drug reaction (ATB-Ctrl subjects). The untargeted metabolome revealed that 77 metabolites (of 895 total) were significantly changed with ATB-DILI progression. Among them, levels of multiple fatty acids and bile acids significantly increased over time in ATB-DILI subjects. Meanwhile, metabolites of the same class were highly correlated with each other and pathway analysis indicated both fatty acids metabolism and bile acids metabolism were up-regulated with ATB-DILI progression. The targeted metabolome further validated that 5 fatty acids had prediction capability at the early stage of the disease and 6 bile acids had a better diagnostic performance when ATB-DILI occurred. These findings provide evidence indicating that fatty acids metabolism and bile acids metabolism play a vital role during ATB-DILI progression. Our report adds a dynamic perspective better to understand the pathological process of ATB-DILI in clinical settings.

A 224-bp Indel in the Promoter of PeMYB114 Accounts for Anthocyanin Accumulation of Skin in Passion Fruit (Passiflora spp.).

Passion fruit (Passiflora spp.) is an important fruit tree in the family Passifloraceae. The color of the fruit skin, a significant agricultural trait, is determined by the content of anthocyanin in passion fruit. However, the regulatory mechanisms behind the accumulation of anthocyanin in different passion fruit skin colors remain unclear. In the study, we identified and characterized a R2R3-MYB transcription factor, PeMYB114, which functions as a transcriptional activator in anthocyanin biosynthesis. Yeast one-hybrid system and dual-luciferase analysis showed that PeMYB114 could directly activate the expression of anthocyanin structural genes (PeCHS and PeDFR). Furthermore, a natural variation in the promoter region of PeMYB114 alters its expression. PeMYB114purple accessions with the 224-bp insertion have a higher anthocyanin level than PeMYB114yellow accessions with the 224-bp deletion. The findings enhance our understanding of anthocyanin accumulation in fruits and provide genetic resources for genome design for improving passion fruit quality.

[Determination of seven perfluoroalkyl and polyfluoroalkyl substances in serum of pregnant women and evaluation of neonatal neurobehavior based on high performance liquid chromatography-tandem mass spectrometry].

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) have been extensively used as synthetic fluorine-containing compounds in various consumer products, including surfactants, cookware, lubricants, clothing, and food packaging, since the 1950s. Evidence has shown that PFASs cross the placental barrier and interfere with fetal thyroid hormone homeostasis, which is crucial for fetal growth and neurobehavioral development in children aged 2-9 years. However, no epidemiological data on the association between prenatal PFAS exposure and neonatal neurobehavioral development are available. In this study, we explored the association between prenatal PFAS exposure and neonatal neurobehavioral development based on the Ezhou cohort study. Blood samples (10 mL) were collected during the third trimester of pregnancy (28-36 weeks) at the Ezhou maternal and child health hospital. The blood specimens were centrifuged at 4000 r/min for 15 min immediately after collection, separated, stored at -80 ℃. The samples were analyzed for seven PFASs, namely, perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroheptanesulfonic acid (PFHpS), and perfluorooctane sulfonamide (PFOSA). The PFASs were separated using a C18 column (100 mm×2.1 mm, 1.7 µm) at an oven temperature of 40 ℃, injection volume of 10 µL, and flow rate of 0.4 mL/min via gradient elution with methanol and ammonium acetate aqueous solution. The instrument was operated in negative electrospray ionization mode with multiple reaction monitoring. The correlation coefficients (r2), limits of detection (LODs) and quantification (LOQs), and spiked recoveries of the seven PFASs were 0.993-0.999, 0.006-0.020 ng/mL, 0.020-0.066 ng/mL, and 84.6%-116.8%, respectively. Neonatal behavioral neurological assessment (NBNA) was used to evaluate newborn cognitive development 72 h after birth; this tool consisted of five clusters, including behavior (six items), passive muscle tone (four items), active muscle tone (four items), primitive reflexes (three items), and general assessment (three items). Each item was rated on a three-point scale (0, 1, or 2), with the 20 items having a maximum score of 40. A total of 379 mother-newborn pairs were included in the analysis. The PFASs with the highest exposure levels was PFOA, with median levels of 19.4 ng/mL. Linear regression models were used to test the effects of ln-converted PFAS levels in newborns. After adjusting for confounding factors, the linear regression model showed that PFOS exposure during pregnancy was associated with decreased active muscle tone(ß(95% CI): 0.36(-0.64, 0.08)) and general assessment(ß(95% CI): 0.34(-0.61, 0.07)) in all newborns. Furthermore, PFNA exposure was associated with decreased passive muscle tone(ß(95% CI): 0.38(-0.74, 0.01)) and total NBNA(ß(95% CI): 0.37(-0.68, 0.06)). PFDA exposure was associated with decreased behavior(ß(95% CI): 0.28(-0.54, 0.01)), while PFHxS exposure was associated with elevated total NBNA(ß(95% CI): 0.27(0.05-0.48)). Gender stratification analysis showed that PFOS exposure during pregnancy was associated with decreased active muscle tone(ß(95% CI): 0.54(-0.73, 0.35)) and general assessment(ß(95% CI): 0.50(-0.88, 0.13)), PFNA exposure during pregnancy was associated with decreased passive muscle tone(ß(95% CI): 0.67(-1.2, 0.14)) and total NBNA(ß(95% CI): 0.45(-0.91, 0.01)), PFDA exposure during pregnancy was associated with decreased behavior(ß(95% CI): 0.44(-0.71, 0.17)), PFHxS exposure was associated with elevated total NBNA(ß(95% CI): 0.41(0.02-0.80)) in male newborns, and PFOA exposure was associated with decreased general assessment(ß(95% CI): -0.27(-0.51, 0.02)), and PFDA exposure was associated with elevated behavior(ß(95% CI): 0.46(0.40-0.52)) in female newborns. The proposed method separates and detects various PFASs without the need for cumbersome pretreatment processes, and has the advantages of low LODs, satisfactory recoveries, and accurate precision. Thus, it allows for the simultaneous analysis of trace PFASs in microserum samples from pregnant women. Our results also showed that prenatal PFAS exposure can lead to neurobehavioral disorders in offspring, with male newborns showing greater sensitivity than female newborns.

Regression analysis of longitudinal data with random change point.

A great deal of literature has been established for regression analysis of longitudinal data and in particular, many methods have been proposed for the situation where there exist some change points. However, most of these methods only apply to continuous response and focus on the situations where the change point only occurs on the response or the trend of the individual trajectory. In this article, we propose a new joint modeling approach that allows not only the change point to vary for different subjects or be subject-specific but also the effect heterogeneity of the covariates before and after the change point. The method combines a generalized linear mixed effect model with a random change point for the longitudinal response and a log-linear regression model for the random change point. For inference, a maximum likelihood estimation procedure is developed and the asymptotic properties of the resulting estimators, which differ from the standard asymptotic results, are established. A simulation study is conducted and suggests that the proposed method works well for practical situations. An application to a set of real data on COVID-19 is provided.

Efficient estimation of Cox model with random change point.

In clinical studies, the risk of a disease may dramatically change when some biological indexes of the human body exceed some thresholds. Furthermore, the differences in individual characteristics of patients such as physical and psychological experience may lead to subject-specific thresholds or change points. Although a large literature has been established for regression analysis of failure time data with change points, most of the existing methods assume the same, fixed change point for all study subjects. In this paper, we consider the situation where there exists a subject-specific change point and two Cox type models are presented. The proposed models also offer a framework for subgroup analysis. For inference, a sieve maximum likelihood estimation procedure is proposed and the asymptotic properties of the resulting estimators are established. An extensive simulation study is conducted to assess the empirical performance of the proposed method and indicates that it works well in practical situations. Finally the proposed approach is applied to a set of breast cancer data.

Development of organic three-phase laminar flow microfluidic chip for extraction of ginsenosides from Panax ginseng.

BACKGROUND: Herbal extracts contain multiple active constituents, so the sample preparation based on the liquid-liquid extraction (LLE) is demanding, especially when a study subsequent to extraction is needed. Since the laminar flow occurring in microchannels can be formed between two miscible organic phases, a new method of extracting polar compounds from the crude extract of Panax ginseng Meyer in aqueous ethanol by pure n-butanol in the three-phase laminar flow microfluidic chip was established. METHODS: A new chip consisting of long microchannels with a guide structure was employed to improve the extraction efficiency caused by the low diffusion ability of saponins. The method was evaluated by using the extraction yields and purities of ginsenosides Rg1, Re and Rb1 as the indicators, and extraction conditions such as flow rate, temperature and other governing factors were optimized. RESULTS: Using the new chip method, the extraction efficiencies of ginsenoside Rg1, Re and Rb1 were 63.1%, 69.5% and 71.6%, respectively, which are higher than the 26% achieved in a previous report. The extraction yields of 1.53, 0.51, 0.90 mg/g were also higher than those obtained previously by the successive laminar flow microchip method. CONCLUSION: The proposed new microfluidic chip method has simplified the sample pretreatment steps to improve the yield of ginsenoside extraction from ginseng samples.

A Propensity Score-Matched Study on the Changes of TB Status and TB-IGRA Values in Patients with Psoriasis with Latent TB Receiving Secukinumab.

INTRODUCTION: The utilization of biologics in patients with psoriasis with latent tuberculosis infection (LTBI) has garnered significant attention. Although the tuberculosis (TB) safety profile of second-generation biologics, including secukinumab, has been partially confirmed in both clinical trials and real-world studies, the necessity for prophylactic therapy in patients with LTBI prior to administering this class of biologics remains a topic of controversy. METHODS: This study enrolled 62 patients with psoriasis with LTBI who underwent secukinumab with routine TB reexamination. Patients were divided into two groups based on whether they received antituberculosis therapy (ATB; n = 48) or not (NTB; n = 16). We performed a propensity score-matched (PSM) analysis between ATB and NTB subgroups and retrospectively reviewed their interferon-gamma release assays (IGRA) and radiographic results. RESULTS: No active TB case was reported on the basis of medical records and chest radiographs in either two group. Before PSM, the mean reexamining IGRA value was significantly elevated in patients who received prophylactic therapy (P = 0.00), but no significant increase was observed in patients who were not. After PSM, there was no significant IGRA value enhancement whether or not patients received prophylactic treatment. CONCLUSION: Our data provide additional information on the safety profile of secukinumab in patients with psoriasis with LTBI. Furthermore, our presentation of the reexamined IGRA results revealed no significant elevation in the ATB or NTB group. As such, we believe further exploration is necessary to determine whether anti-TB medication is required prior to administering secukinumab.

In the past decade, biologics have revolutionized psoriasis treatment. Among patients receiving biologics, tuberculosis infection is a big concern. Secukinumab, an interleukin-17 inhibitor, belongs to the second-generation biologics. Clinical trials and real-life experience have partially reported its tuberculosis safety. In 2020, a systematic review of randomized clinical trials of secukinumab found no reactivate tuberculosis case. However, when participants tested positive for latent tuberculosis infection at screening in the clinical trials, they received antituberculosis treatment. Should patients with latent tuberculosis infection receive antituberculosis medication before receiving secukinumab? The answer is controversial and lacks evidence. This study enrolled patients with psoriasis with latent tuberculosis infection who underwent secukinumab with routine tuberculosis reexamination. Then, the patients were divided into two groups based on whether they received antituberculosis therapy and not. We observed that neither of these two groups presented tuberculosis activation cases. We also matched patients who received antituberculosis therapy and those who did not. The interferon-gamma release assay showed no significant increase after balancing the baseline. Our data indicated that secukinumab is safe among patients with latent tuberculosis infection even when they did not receive antituberculosis treatment.

Monodentate Transient Directing Group-Assisted Palladium-Catalyzed Direct ortho-C-H Iodination of Benzaldehydes for Total Synthesis of Hernandial.

The first palladium-catalyzed direct o-C-H iodination of benzaldehydes was successfully developed with the assistance of commercially available 2,5-bis(trifluoromethyl)aniline as the optimal monodentate transient directing group (MonoTDG). Moderate to excellent yields and good selectivity were achieved for a broad substrate scope under mild conditions. More importantly, the synthetic application was demonstrated by a concise two-step total synthesis of the natural product hernandial, which was accomplished by merging this new MonoTDG-assisted C-H iodination and subsequent copper-catalyzed cross-coupling.

Transient Directing Group Strategy as a Unified Method for Site Selective Direct C4-H Halogenation of Indoles.

A unified method for direct C4-H halogenation of indoles has been accomplished with the assistance of anthranilic acids as suitable transient directing groups. Exclusive site selectivity (one out of five potential reactive sites) as well as good functional group tolerance was obtained to install three kinds of halogen atoms (Cl, Br and I, respectively) by using inexpensive N-halosuccinimides (NXS) as halogen sources under mild conditions. Taking advantage of the rich functional groups in the product, a diversity of nitrogen-containing heterocycles were facily constructed via one-step late-stage derivations.

Mechanical stimuli-mediated modulation of bone cell function-implications for bone remodeling and angiogenesis.

Bone remodeling, expressed as bone formation and turnover, is a complex and dynamic process closely related to its form and function. Different events, such as development, aging, and function, play a critical role in bone remodeling and metabolism. The ability of the bone to adapt to new loads and forces has been well known and has proven useful in orthopedics and insightful for research in bone and cell biology. Mechanical stimulation is one of the most important drivers of bone metabolism. Interestingly, different types of forces will have specific consequences in bone remodeling, and their beneficial effects can be traced using different biomarkers. In this narrative review, we summarize the major mediators and events in bone remodeling, focusing on the effects of mechanical stimulation on bone metabolism, cell populations, and ultimately, bone health.

Pulmonary alveolar proteinosis complicated with tuberculosis: A case report.

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is a rare lung disease characterized by the accumulation of phospholipoproteinaceous material in the alveoli. Cases of PAP complicated with tuberculosis are much more complex and have rarely been well recorded. CASE SUMMARY: We describe a 21-year-old Han Chinese patient with suspicious lung infection associated with mild restrictive ventilatory dysfunction and diffusion reduction. High resolution computed tomography revealed a "crazy-paving" appearance and multiple pulmonary miliary nodules around the bronchi. Bronchoalveolar lavage demonstrated a small amount of periodic acid-Schiff positive proteinaceous materials. A serological test for the presence of a Mycobacterium tuberculosis antibody and an interferon-gamma release assay were both positive. The patient received a standard course of first-line anti-tuberculosis treatment after diagnostic bronchoalveolar lavage. To date, clinical remission has been achieved and maintained for five years. CONCLUSION: In summary, the diagnosis of PAP complicated with tuberculosis was supported by a combination of clinical manifestations, imaging, pulmonary function, laboratory examinations, bronchoalveolar lavage, etc. This case highlighted that diagnostic bronchoalveolar lavage in combination with anti-tuberculosis treatment is a safe and effective option for mild PAP patients with tuberculosis.

Strategies for advanced personalized tuberculosis diagnosis: Current technologies and clinical approaches.

Diagnosis of tuberculosis can be difficult as advances in molecular diagnosis approaches (especially nanoparticles combined with high-throughput mass spectrometry for detecting mycobacteria peptide) and personalized medicine result in many changes to the diagnostic framework. This review will address issues concerning novel technologies from bench to bed and new strategies for personalized tuberculosis diagnosis.

Mesenchymal stem cells as a double-edged sword in tumor growth: focusing on MSC-derived cytokines.

Mesenchymal stem cells (MSCs) show homing capacity towards tumor sites. Numerous reports indicate that they are involved in multiple tumor-promoting processes through several mechanisms, including immunosuppression; stimulation of angiogenesis; transition to cancer-associated fibroblasts; inhibition of cancer cell apoptosis; induction of epithelial-mesenchymal transition (EMT); and increase metastasis and chemoresistance. However, other studies have shown that MSCs suppress tumor growth by suppressing angiogenesis, incrementing inflammatory infiltration, apoptosis and cell cycle arrest, and inhibiting the AKT and Wnt signaling pathways. In this review, we discuss the supportive and suppressive impacts of MSCs on tumor progression and metastasis. We also discuss MSC-based therapeutic strategies for cancer based on their potential for homing to tumor sites.

Nanotechnology shaping stem cell therapy: Recent advances, application, challenges, and future outlook.

Currently, stem cell nanotechnology is one of the novel and exciting fields. Certain experimental studies conducted on the interaction of stem cells with nanostructures or nanomaterials have made significant progress. The significance of nanostructures, nanotechnology, and nanomaterials in the development of stem cell-based therapies for degenerative diseases and injuries has been well established. Specifically, the structure and properties of nanomaterials affecting the propagation and differentiation of stem cells have become a new interdisciplinary frontier in material science and regeneration medicines. In the current review, we highlight the recent major progress in this field, explore the application prospects, and discuss the issues, approaches, and challenges, to improve the applications of nanotechnology in the research and development of stem cells.

In vivo behavior of bioactive glass-based composites in animal models for bone regeneration.

This review presents the recent advances and the current state-of-the-art of bioactive glass-based composite biomaterials intended for bone regeneration. Composite materials comprise two (or more) constituents at the nanometre scale, in which typically, one constituent is organic and functions as the matrix phase and the other constituent is inorganic and behaves as the reinforcing phase. Such materials, thereby, more closely resemble natural bio-nanocomposites such as bone. Various glass compositions in combination with a wide range of natural and synthetic polymers have been evaluated in vivo under experimental conditions ranging from unloaded critical-sized defects to mechanically-loaded, weight-bearing sites with highly favourable outcomes. Additional possibilities include controlled release of anti-osteoporotic drugs, ions, antibiotics, pro-angiogenic substances and pro-osteogenic substances. Histological and morphological evaluations suggest the formation of new, highly vascularised bone that displays signs of remodelling over time. With the possibility to tailor the mechanical and chemical properties through careful selection of individual components, as well as the overall geometry (from mesoporous particles and micro-/nanospheres to 3D scaffolds and coatings) through innovative manufacturing processes, such biomaterials present exciting new avenues for bone repair and regeneration.

Assessing the role of SH3RF1 and SH3RF2 polymorphisms in susceptibility to tuberculosis: A case-control study in the Han Chinese population.

BACKGROUND: Tuberculosis (TB) remains a major public health problem. SH3RF1 and SH3RF2 are candidate genes with multiple single-nucleotide polymorphisms (SNPs) that have the potential to participate in Mycobacterium infection via activation of the JNK signaling pathway. In this case-control study, we aimed to investigate the association of five SH3RF1 and SH3RF2 SNPs with susceptibility to TB in the Western Chinese population. METHODS: A total of 900 TB patients and 1534 healthy control subjects were enrolled in our study. All samples used were obtained from the Bio-Bank of resources of Tuberculosis Research in the Department of Laboratory Medicine, West China Hospital, Sichuan University, China. SNP genotyping was conducted using a commercial custom-by-design 2 × 48-Plex SNPscan Kit. RESULTS: The rs758037 variant of the SH3RF2 gene was found to be associated with decreased TB risk based on allelic effects (p = 0.00001, OR = 0.731, 95% CI = 0.641-0.833) and three genetic models (padd = 0.00001, pdom = 0.0003, prec = 0.0007) after the data were controlled for age and gender and underwent Bonferroni correction. The rs4913057 variant of the SH3RF2 gene was found to be associated with increased TB risk in a dominant model (p = 0.021, OR: 1.260, 95% CI: 1.065-1.490). No significant association was observed between other SNPs and TB risk. CONCLUSION: These findings indicate that polymorphisms in the SH3RF2 gene are involved in susceptibility to TB in the Western Chinese population.

A rare case report of laryngopharyngeal polyp formation following anterior cervical discectomy and fusion (ACDF).

BACKGROUND: Anterior Cervical Discectomy and Fusion (ACDF) has been regarded as the "gold standard" treatment of cervical spondylosis. Though it has good outcomes, many complications still exist, such as loss of fixation, degeneration of adjacent segments, dysphagia and pharyngeal perforation. In view of current literature, this study is the first to report a case of laryngopharyngeal polyp following ACDF. CASE PRESENTATION: A 63 year old male patient suffered from cervical spine hyperextension after trauma accompanied by numbness of the hands and decreased muscle strength in both upper limbs. Anterior cervical fusion surgery was performed in our hospital, after which the patient's upper limb numbness disappeared and muscle strength returned to normal. In the fifth month after surgery, the patient developed a sore throat and dysphagia. Symptoms gradually worsened, and the patient was hospitalized four times, subsequently undergoing tracheotomy, internal fixation removal, and polypectomy. The patient's pronunciation, breathing, and swallowing functions returned to normal, and the incision healed. After a one-year follow-up, the polyp did not recur. CONCLUSIONS: Laryngopharyngeal polyp formation following ACDF has yet to be reported in literature. By excluding esophageal fistula as soon as possible, removing internal fixation and polypectomy serves as the best treatment in relieving patient symptoms.