RESUMO
Pulsar wind nebulae are formed when outflows of relativistic electrons and positrons hit the surrounding supernova remnant or interstellar medium at a shock front. The Vela pulsar wind nebula is powered by a young pulsar (B0833-45, aged 11,000 years)1 and located inside an extended structure called Vela X, which is itself inside the supernova remnant2. Previous X-ray observations revealed two prominent arcs that are bisected by a jet and counter jet3,4. Radio maps have shown high linear polarization of 60% in the outer regions of the nebula5. Here we report an X-ray observation of the inner part of the nebula, where polarization can exceed 60% at the leading edge-approaching the theoretical limit of what can be produced by synchrotron emission. We infer that, in contrast with the case of the supernova remnant, the electrons in the pulsar wind nebula are accelerated with little or no turbulence in a highly uniform magnetic field.
RESUMO
Spermatogenesis depends on the crosstalk of Sertoli cells (SCs) and germ cells. However, the gene regulatory network establishing the communications between SCs and germ cells remains unclear. Here, we report that heterogeneous nuclear ribonucleoprotein H1 (hnRNPH1) in SCs is essential for the establishment of crosstalk between SCs and germ cells. Conditional knockout of hnRNPH1 in mouse SCs leads to compromised blood-testis barrier function, delayed meiotic progression, increased germ cell apoptosis, sloughing of germ cells and, eventually, infertility of mice. Mechanistically, we discovered that hnRNPH1 could interact with the splicing regulator PTBP1 in SCs to regulate the pre-mRNA alternative splicing of the target genes functionally related to cell adhesion. Interestingly, we also found hnRNPH1 could cooperate with the androgen receptor, one of the SC-specific transcription factors, to modulate the transcription level of a group of genes associated with the cell-cell junction and EGFR pathway by directly binding to the gene promoters. Collectively, our findings reveal a crucial role for hnRNPH1 in SCs during spermatogenesis and uncover a potential molecular regulatory network involving hnRNPH1 in establishing Sertoli-germ cell crosstalk.
Assuntos
Células de Sertoli , Espermatogênese , Animais , Masculino , Camundongos , Fertilidade/fisiologia , Células Germinativas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Camundongos Knockout , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Células de Sertoli/metabolismo , Espermatogênese/genética , Testículo/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Teratozoospermia is a significant cause of male infertility, but the pathogenic mechanism of acephalic spermatozoa syndrome (ASS), one of the most severe teratozoospermia, remains elusive. We previously reported Spermatogenesis Associated 6 (SPATA6) as the component of the sperm head-tail coupling apparatus (HTCA) required for normal assembly of the sperm head-tail conjunction, but the underlying molecular mechanism has not been explored. Here, we find that the co-chaperone protein BAG5, expressed in step 9-16 spermatids, is essential for sperm HTCA assembly. BAG5-deficient male mice show abnormal assembly of HTCA, leading to ASS and male infertility, phenocopying SPATA6-deficient mice. In vivo and in vitro experiments demonstrate that SPATA6, cargo transport-related myosin proteins (MYO5A and MYL6) and dynein proteins (DYNLT1, DCTN1, and DNAL1) are misfolded upon BAG5 depletion. Mechanistically, we find that BAG5 forms a complex with HSPA8 and promotes the folding of SPATA6 by enhancing HSPA8's affinity for substrate proteins. Collectively, our findings reveal a novel protein-regulated network in sperm formation in which BAG5 governs the assembly of the HTCA by activating the protein-folding function of HSPA8.
Assuntos
Proteínas do Citoesqueleto , Infertilidade Masculina , Teratozoospermia , Tiazóis , Animais , Humanos , Masculino , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Dineínas/metabolismo , Proteínas de Choque Térmico HSC70/genética , Proteínas de Choque Térmico HSC70/metabolismo , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Dobramento de Proteína , Sêmen/metabolismo , Cabeça do Espermatozoide/fisiologia , Espermatogênese/genética , Espermatozoides/metabolismo , Teratozoospermia/metabolismo , Teratozoospermia/patologiaRESUMO
Across ecology, and particularly within microbial ecology, there is limited understanding how the generation and maintenance of diversity. Although recent work has shown that both local assembly processes and species pools are important in structuring microbial communities, the relative contributions of these mechanisms remain an important question. Moreover, the roles of local assembly processes and species pools are drastically different when explicitly considering the potential for saturation or unsaturation, yet this issue is rarely addressed. Thus, we established a conceptual model that incorporated saturation theory into the microbiological domain to advance the understanding of mechanisms controlling soil bacterial diversity during forest secondary succession. Conceptual model hypotheses were tested by coupling soil bacterial diversity, local assembly processes and species pools using six different forest successional chronosequences distributed across multiple climate zones. Consistent with the unsaturated case proposed in our conceptual framework, we found that species pool consistently affected α-diversity, even while local assembly processes on local richness operate. In contrast, the effects of species pool on ß-diversity disappeared once local assembly processes were taken into account, and changes in environmental conditions during secondary succession led to shifts in ß-diversity through mediation of the strength of heterogeneous selection. Overall, this study represents one of the first to demonstrate that most local bacterial communities might be unsaturated, where the effect of species pool on α-diversity is robust to the consideration of multiple environmental influences, but ß-diversity is constrained by environmental selection.
Assuntos
Biodiversidade , Microbiota , Florestas , Ecologia , Bactérias/genética , Solo , EcossistemaRESUMO
BACKGROUND: It's unclear if excess visceral adipose tissue (VAT) mass in individuals with prediabetes can be countered by adherence to a Mediterranean lifestyle (MEDLIFE). We aimed to examine VAT mass, MEDLIFE adherence, and their impact on type 2 diabetes (T2D) and diabetic microvascular complications (DMC) in individuals with prediabetes. METHODS: 11,267 individuals with prediabetes from the UK Biobank cohort were included. VAT mass was predicted using a non-linear model, and adherence to the MEDLIFE was evaluated using the 25-item MEDLIFE index, encompassing categories such as "Mediterranean food consumption," "Mediterranean dietary habits," and "Physical activity, rest, social habits, and conviviality." Both VAT and MEDLIFE were categorized into quartiles, resulting in 16 combinations. Incident cases of T2D and related DMC were identified through clinical records. Cox proportional-hazards regression models were employed to examine associations, adjusting for potential confounding factors. RESULTS: Over a median follow-up of 13.77 years, we observed 1408 incident cases of T2D and 714 cases of any DMC. High adherence to the MEDLIFE, compared to the lowest quartile, reduced a 16% risk of incident T2D (HR: 0.84, 95% CI: 0.71-0.98) and 31% for incident DMC (0.69, 0.56-0.86). Conversely, compared to the lowest quartile of VAT, the highest quartile increased the risk of T2D (5.95, 4.72-7.49) and incident any DMC (1.79, 1.36-2.35). We observed an inverse dose-response relationship between MEDLIFE and T2D/DMC, and a dose-response relationship between VAT and all outcomes (P for trend < 0.05). Restricted cubic spline analysis confirmed a nearly linear dose-response pattern across all associations. Compared to individuals with the lowest MEDLIFE quartile and highest VAT quartile, those with the lowest T2D risk had the lowest VAT and highest MEDLIFE (0.12, 0.08-0.19). High MEDLIFE was linked to reduced T2D risk across all VAT categories, except in those with the highest VAT quartile. Similar trends were seen for DMC. CONCLUSION: High adherence to MEDLIFE reduced T2D and MDC risk in individuals with prediabetes, while high VAT mass increases it, but MEDLIFE adherence may offset VAT's risk partly. The Mediterranean lifestyle's adaptability to diverse populations suggests promise for preventing T2D.
Assuntos
Diabetes Mellitus Tipo 2 , Angiopatias Diabéticas , Dieta Mediterrânea , Gordura Intra-Abdominal , Estado Pré-Diabético , Fatores de Proteção , Comportamento de Redução do Risco , Humanos , Estado Pré-Diabético/epidemiologia , Estado Pré-Diabético/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Gordura Intra-Abdominal/fisiopatologia , Idoso , Fatores de Risco , Medição de Risco , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/diagnóstico , Angiopatias Diabéticas/prevenção & controle , Fatores de Tempo , Incidência , Adiposidade , Reino Unido/epidemiologia , Adulto , Dieta Saudável , Exercício Físico , Estilo de Vida Saudável , Obesidade Abdominal/diagnóstico , Obesidade Abdominal/epidemiologia , Obesidade Abdominal/fisiopatologia , Estudos ProspectivosRESUMO
BACKGROUND AND OBJECTIVES: To determine early continence outcomes after three-layer vesicourethral reconstruction during robot-assisted radical prostatectomy (RARP) and the role of postoperative cystography pattern. METHODS: Between May 2015 and January 2019, a total of 170 consecutive patients with localized prostate cancer who underwent RARP, were divided into one- and three-layer groups based on the method of vesicourethral reconstruction. Continent status, preoperative, intraoperative, postoperative, clinicopathological variables, and cystography parameters were analyzed. The patients were followed up for at least 12 months. RESULTS: Of the 170 consecutive patients, 85 with one-layer vesicourethral anastomosis, and 85 with three-layer reconstruction. The continence rates immediately after catheter removal, 4, 12, and 24 weeks after RARP were 47.1%, 75.3%, 92.9%, and 98.8% in the three-layer group; compared to 15.3%, 60%, 78.8%, and 90.6% in the one-layer group, respectively. In the multivariate analysis, three-layer reconstruction was the only independent variable with a 42% risk reduction of postprostatectomy incontinence (hazard ratio (HR): 0.58, 95% confidence interval (CI) = 0.42-0.80, p = 0.001). Cystography in the three-layer group revealed less anastomotic leakage, less sharp bladder neck angle, and higher bladder neck level category. CONCLUSIONS: Three-layer anatomical reconstruction demonstrated promising early continence outcomes, and postoperative cystography revealed a specific pattern more associated with continence.
Assuntos
Cistografia , Procedimentos de Cirurgia Plástica , Prostatectomia , Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Uretra , Bexiga Urinária , Incontinência Urinária , Humanos , Masculino , Prostatectomia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Uretra/cirurgia , Uretra/diagnóstico por imagem , Bexiga Urinária/cirurgia , Bexiga Urinária/diagnóstico por imagem , Pessoa de Meia-Idade , Incontinência Urinária/etiologia , Incontinência Urinária/prevenção & controle , Procedimentos de Cirurgia Plástica/métodos , Cistografia/métodos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Seguimentos , Estudos Retrospectivos , Recuperação de Função Fisiológica , PrognósticoRESUMO
Patients with end-stage kidney disease (ESKD) rely on dialysis to remove toxins and stay alive. However, hemodialysis alone is insufficient to completely remove all/major uremic toxins, resulting in the accumulation of specific toxins over time. The complexity of uremic toxins and their varying clearance rates across different dialysis modalities poses significant challenges, and innovative approaches such as microfluidics, biomarker discovery, and point-of-care testing are being investigated. This review explores recent advances in the qualitative and quantitative analysis of uremic toxins and highlights the use of innovative methods, particularly label-mediated and label-free surface-enhanced Raman spectroscopy, primarily for qualitative detection. The ability to analyze uremic toxins can optimize hemodialysis settings for more efficient toxin removal. Integration of multiple omics disciplines will also help identify biomarkers and understand the pathogenesis of ESKD, provide deeper understanding of uremic toxin profiling, and offer insights for improving hemodialysis programs. This review also highlights the importance of early detection and improved understanding of chronic kidney disease to improve patient outcomes.
Assuntos
Falência Renal Crônica , Insuficiência Renal Crônica , Toxinas Urêmicas , Humanos , Falência Renal Crônica/terapia , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/diagnóstico , Toxinas Urêmicas/análise , Progressão da Doença , Análise Espectral Raman/métodos , Biomarcadores/análise , Biomarcadores/sangue , Diálise RenalRESUMO
Two novel MoO42--templated luminescent silver alkynyl nanoclusters with 20-nuclearity ([(MoO42-)@Ag20(C≡CtBu)8(Ph2PO2)7(tfa)2]·(tfa-) (1)) and 18-nuclearity ([(MoO42-)@Ag18(C≡CtBu)8(Ph2PO2)7]·(OH) (2)) (tfa = trifluoroacetate) were synthesized with the green light maximum emissions at 507 and 516 nm, respectively. The nanoclusters were investigated and characterized by single-crystal X-ray crystallography, electrospray ionization mass spectrum (ESI-MS), X-ray photoelectron spectroscopy, thermogravimetry (TG), photoluminescence (PL), ultraviolet-visible (UV-vis) spectroscopy, and density functional theory calculations (DFT). The two nanoclusters differ in their structure by a supplementary [Ag2(tfa)2] organometallic surface motif, which significantly participates in the frontier molecular orbitals of 1, resulting in similar bonding patterns but different optical properties between the two clusters. Indeed, both nanoclusters show strong temperature-dependent photoluminescence properties, which make them potential candidates in the fields of optical devices for further applications.
RESUMO
Rationale: Invasive ventilation is a significant event for patients with respiratory failure. Physiologic thresholds standardize the use of invasive ventilation in clinical trials, but it is unknown whether thresholds prompt invasive ventilation in clinical practice. Objectives: To measure, in patients with hypoxemic respiratory failure, the probability of invasive ventilation within 3 hours after meeting physiologic thresholds. Methods: We studied patients admitted to intensive care receiving FiO2 of 0.4 or more via nonrebreather mask, noninvasive positive pressure ventilation, or high-flow nasal cannula, using data from the Medical Information Mart for Intensive Care (MIMIC)-IV database (2008-2019) and the Amsterdam University Medical Centers Database (AmsterdamUMCdb) (2003-2016). We evaluated 17 thresholds, including the ratio of arterial to inspired oxygen, the ratio of saturation to inspired oxygen ratio, composite scores, and criteria from randomized trials. We report the probability of invasive ventilation within 3 hours of meeting each threshold and its association with covariates using odds ratios (ORs) and 95% credible intervals (CrIs). Measurements and Main Results: We studied 4,726 patients (3,365 from MIMIC, 1,361 from AmsterdamUMCdb). Invasive ventilation occurred in 28% (1,320). In MIMIC, the highest probability of invasive ventilation within 3 hours of meeting a threshold was 20%, after meeting prespecified neurologic or respiratory criteria while on vasopressors, and 19%, after a ratio of arterial to inspired oxygen of <80 mm Hg. In AmsterdamUMCdb, the highest probability was 34%, after vasopressor initiation, and 25%, after a ratio of saturation to inspired oxygen of <90. The probability after meeting the threshold from randomized trials was 9% (MIMIC) and 13% (AmsterdamUMCdb). In MIMIC, a race/ethnicity of Black (OR, 0.75; 95% CrI, 0.57-0.96) or Asian (OR, 0.6; 95% CrI, 0.35-0.95) compared with White was associated with decreased probability of invasive ventilation after meeting a threshold. Conclusions: The probability of invasive ventilation within 3 hours of meeting physiologic thresholds was low and associated with patient race/ethnicity.
Assuntos
Ventilação não Invasiva , Insuficiência Respiratória , Humanos , Ventilação não Invasiva/efeitos adversos , Estudos de Coortes , Intubação Intratraqueal , Hipóxia/complicações , Insuficiência Respiratória/etiologia , Oxigênio , Cânula , OxigenoterapiaRESUMO
BACKGROUND: Economic relief programs are strategies designed to sustain societal welfare and population health during a regional or global scale infectious disease outbreak. While economic relief programmes are considered essential during a regional or global health crisis, there is no clear consensus in the literature about their health and non-health benefits and their impact on promoting equity. METHODS: We conducted a scoping review, searching eight electronic databases from January 01, 2001, to April 3, 2023, using text words and subject headings for recent pathogens (coronavirus (COVID-19), Ebola, Influenza, Middle East Respiratory Syndrome (MERS), severe acute respiratory syndrome (SARS), HIV, West Nile, and Zika), and economic relief programs; but restricted eligibility to high-income countries and selected diseases due to volume. Title and abstract screening were conducted by trained reviewers and Distiller AI software. Data were extracted in duplicates by two trained reviewers using a pretested form, and key findings were charted using a narrative approach. RESULTS: We identified 27,263 de-duplicated records, of which 50 were eligible. Included studies were on COVID-19 and Influenza, published between 2014 and 2023. Zero eligible studies were on MERS, SARS, Zika, Ebola, or West Nile Virus. We identified seven program types of which cash transfer (n = 12) and vaccination or testing incentive (n = 9) were most common. Individual-level economic relief programs were reported to have varying degrees of impact on public health measures, and sometimes affected population health outcomes. Expanding paid sick leave programs had the highest number of studies reporting health-related outcomes and positively impacted public health measures (isolation, vaccination uptake) and health outcomes (case counts and the utilization of healthcare services). Equity impact was most often reported for cash transfer programs and incentive for vaccination programs. Positive effects on general well-being and non-health outcomes included improved mental well-being and quality of life, food security, financial resilience, and job security. CONCLUSIONS: Our findings suggest that individual-level economic relief programs can have significant impacts on public health measures, population health outcomes and equity. As countries prepare for future pandemics, our findings provide evidence to stakeholders to recognize health equity as a fundamental public health goal when designing pandemic preparedness policies.
Assuntos
Pandemias , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/economia , Países Desenvolvidos , Socorro em Desastres/economia , Epidemias/prevenção & controle , Equidade em SaúdeRESUMO
BACKGROUND: Femoral neck fractures in older adult patients are a major concern and often necessitate surgical intervention. This study compared the clinical outcomes of 2 surgical techniques: the femoral neck system (FNS) and cannulated compression screws (CCSs). METHODS: A total of 40 female patients (mean age 73.50 ± 11.55 years) with femoral neck fractures of Pauwels classification type II and receiving surgical fixation between 2020 and 2022 were enrolled. The patients were categorized into an FNS group (n = 12) or a CCS group (n = 28), and surgical duration, intraoperative blood loss, length of hospital stay, and incidence of postoperative adverse events were analyzed. RESULTS: No significant intergroup differences in demographic characteristics were discovered. The mean surgical duration for all patients was 52.88 ± 22.19 min, with no significant difference between the groups. However, the FNS group experienced significantly higher intraoperative blood loss (P = 0.002) and longer hospital stay (P = 0.023) than did the CCS group. The incidence of osteonecrosis was higher in the CCS group, whereas the incidence of nonunion or malunion was higher in the FNS group. The surgical method did not appear to be a significant risk factor. The main risk factor for revision surgery was longer duration until the first adverse event (P = 0.015). CONCLUSION: The FNS does not appear to provide superior surgical outcomes compared with CCSs in older adult women with Pauwels classification type II femoral neck fractures. A longer duration between surgical fixation and the first adverse event before stabilization of the fracture site may be a risk factor for revision surgery.
Assuntos
Fraturas do Colo Femoral , Necrose da Cabeça do Fêmur , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Colo do Fêmur , Perda Sanguínea Cirúrgica , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Fraturas do Colo Femoral/cirurgia , Fraturas do Colo Femoral/etiologia , Necrose da Cabeça do Fêmur/etiologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak posed impact on healthcare. This study evaluated the effect of SARS-CoV-2 outbreak on the outpatient visits of patients with type 2 diabetes and determined the most affected groups. We analyzed Taiwan's National Health Insurance data, including 1,922,702 patients diagnosed with type 2 diabetes from 2018 to 2021. Group-based trajectory modelling identified four distinct outpatient visit patterns, namely, consistently high (Group 1, 74.2%), low-to-high (Group 2, 8.1%), high-to-low (Group 3, 6.0%) and consistently low (Group 4, 11.7%) utilization. Logistic regression was used to analyze correlations between trajectory types and patients' demographics and health statuses. Group 3 members had higher odds of being male [adjusted odds ratio (aOR) = 1.04, 95% confidence interval (CI) 1.03-1.05] and earning below 20,000 New Taiwan Dollar monthly (aOR = 1.29, 95% CI 1.26-1.31) than those in Group 1. However, they were less likely to be under 80 years old (aOR = 0.70-0.97), from lower median family income regions (aOR = 0.81-0.89) or possess a Charlson Comorbidity Index score > 2 (aOR = 0.67, 95% CI 0.66-0.68). Patients with lower income in affluent areas displayed the highest likelihood of falling into Group 3. Patients with type 2 diabetes and low income from wealthy areas were vulnerable during the pandemic. This result emphasizes the need to target resources and support for this subgroup during such crises.
Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Humanos , Masculino , Idoso de 80 Anos ou mais , Feminino , Diabetes Mellitus Tipo 2/epidemiologia , SARS-CoV-2 , Disparidades Socioeconômicas em Saúde , Taiwan/epidemiologia , Pacientes Ambulatoriais , COVID-19/epidemiologiaRESUMO
Undersea earthquake-triggered giant tsunamis pose significant threats to coastal areas, spanning thousands of kilometers and affecting populations, ecosystems, and infrastructure. To mitigate their impact, monitoring seismic activity in underwater environments is crucial. In this study, we propose a new, to the best of our knowledge, approach for monitoring vibrations in submarine optical cables. By detecting vibration-induced polarization rotation, our dual-wavelength fiber-optic sensing system enables precise measurement of acoustic/vibration amplitude, frequency, and position. As a proof of concept, a double-ended forward-transmission distributed fiber-optic vibration sensor was demonstrated with a single vibration source with a sensitivity of 3.4â mrad/µÎµ at 100â Hz (20 m fiber on PZT), limit of detection of 1.7â pε/Hz1/2 at 100â Hz, sensing range of 121.5â km without an optical amplifier, spatial resolution of 5 m, and position error as small as 34 m. The vibration frequency range tested is from 0.01 to 100â Hz. The sensing system has several advantages, including elegant setup, noise mitigation, and super-long sensing distance.
RESUMO
Long-range vibration sensing is an important tool for real-time structural health monitoring. A new, to the best of our knowledge, design of a distributed fiber-optic vibration sensor is introduced and experimentally demonstrated in this study. The proposed system utilizes the transmission of light in the forward direction for sensing, and a self-interference method for laser source simplification. To extract vibration information from phase modulation of light, two Mach-Zehnder interferometers (MZIs) are employed with a 3 × 3 coupler-based differential cross multiplication algorithm for phase calculation. A folded double-ended detection configuration allows the time-of-flight difference via cross correlation (CC) to provide vibration positioning. Experimental results demonstrate a sensing range of up to â¼80â km without optical amplification, accompanied by a position accuracy of 336 m.
RESUMO
This publisher's note contains corrections to Opt. Lett.48, 4825 (2023)10.1364/OL.500587.
RESUMO
The terahertz (THz) band has a great potential for the development of communication technology, but it has not been fully utilized due to the lack of practical devices, especially actively controllable multifunctional devices. Here, we propose and demonstrate a Ge2Sb2Te5 (GST)-based metamaterial device, where an actively controllable function is experimentally verified by inducing the crystallization process with thermal activation. Cross-polarization conversion in the reflection mode and circular-to-linear polarization conversion in the transmission mode are obtained under crystalline and amorphous GST conditions, respectively. The combination of GST and THz waves has a wide range of applications and will further advance the THz field.
RESUMO
OBJECTIVE: This meta-analysis aimed to assess the association between vitamin B6 intake, blood PLP levels, and the risk of colorectal cancer. METHODS: The databases PubMed, Cochrane Library and Embase databases were comprehensively searched for cohort studies or case-control studies. The odds ratio (OR) and 95% confidence interval (CI) were extracted from each eligible study, and the statistical software Stata was used to perform statistical merging. RESULTS: Twenty-eight studies (20 cohort studies, 8 case-control studies) were included in our meta-analysis. The combined OR for the association between colorectal cancer risk and vitamin B6 intake was 0.80 (95% CI: 0.68-0.94), while the combined OR between blood PLP levels and colorectal cancer risk was 0.54 (95% CI: 0.35-0.84). In addition, the subgroup analysis revealed that vitamin B6 could reduce the risk of colorectal cancer in women [vitamin B6 intake OR = 0.79, 95% CI (0.65-0.96); blood PLP levels OR = 0.41, 95% CI (0.30-0.57)] and also reduce the risk of colon cancer in men and women [vitamin B6 intake OR = 0.76, 95% CI (0.64-0.91); blood PLP levels OR = 0.56, 95% CI (0.42-0.73)]. CONCLUSION: In this meta-analysis, vitamin B6 intake and blood PLP levels were inversely associated with colorectal cancer risk.
Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Feminino , Humanos , Masculino , Estudos de Coortes , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Estado Nutricional , Risco , Vitamina B 12 , Vitamina B 6 , Estudos Observacionais como AssuntoRESUMO
BACKGROUND: Research on the association of physical activity and sedentary time with dementia is accumulating, though elusive, and the interaction effects of the two remain unclear. We analysed the joint associations of accelerometer-measured physical activity and sedentary time with risk of incident dementia (all-cause dementia, Alzheimer's disease and vascular dementia). METHODS: A total of 90,320 individuals from the UK Biobank were included. Accelerometer-measured total volume of physical activity (TPA) and sedentary time were measured at baseline and dichotomised by median (low TPA [< 27 milli-gravity (milli-g)], high TPA [≥ 27 milli-g]; low sedentary time [< 10.7 h/day], high sedentary time [≥ 10.7 h/day]). Cox proportional hazards models were used to evaluate the joint associations with incident dementia on both additive and multiplicative scales. RESULTS: During a median follow-up of 6.9 years, 501 cases of all-cause dementia were identified. Higher TPA was associated with a lower risk of all-cause dementia, Alzheimer's disease and vascular dementia; the multivariate adjusted hazard ratios (HRs) (95% CI) per 10 milli-g increase were 0.63 (0.55-0.71), 0.74 (0.60-0.90) and 0.69 (0.51-0.93), respectively. Sedentary time was only found to be linked to all-cause dementia, and the HR for high sedentary time was 1.03 (1.01-1.06) compared with that for low sedentary time. No additive and multiplicative relationship of TPA and sedentary time to incident dementia was found (all P values > 0.05). CONCLUSION: Higher TPA level was related to a lower risk of incident dementia irrespective of sedentary time, which highlighted the implication of promoting physical activity participation to counteract the potential detrimental effect of sedentary time on dementia.
Assuntos
Doença de Alzheimer , Demência Vascular , Humanos , Estudos de Coortes , Doença de Alzheimer/epidemiologia , Comportamento Sedentário , Bancos de Espécimes Biológicos , Estudos Prospectivos , Exercício Físico , Acelerometria , Reino Unido/epidemiologia , Fatores de RiscoRESUMO
The metallophilic properties, spherical configuration, and flexible coordination of silver ions make them prone to create various coordination modes and structural features. Therefore, with the increase of the complexities of self-assembly, the effect of various synthetic conditions in the final structure of silver compounds becomes diverse and attractive. In this study, two new silver polyclusters, 16- and 21-nuclearity, protected by multiple ligands including alkynyl, trifluoroacetate, and diphenylphosphinate, were synthesized and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, and Fourier transform infrared (FTIR) spectroscopy. The optical properties and thermal stability of the polyclusters were studied by solid-state ultraviolet-visible (UV-vis) absorption and solid UV-vis diffuse reflectance spectra and gravimetric analysis, respectively. The formation of the two polyclusters can be fine-controlled by simply adjusting the stoichiometric ratio of diphenylphosphinate ligands to silver precursors under the same synthetic condition, leading to the different coordination modes between ligands and Ag centers. This work shows a facile and template-free method to synthesize and control the silver polycluster assembly, encouraging further development of new polyclusters with the potential for various applications.
RESUMO
The first mixed-valence nanocluster CuI/CuII with the highest percentage of CuII ions was synthesized by using 4-tert-butylcalix[4]arene (Calix4), with the formula DMF2â[(CO3)2-@CuII6CuI3(Calix4)3Cl2(DMF)5(H3O)]â¢DMF (1), as a photothermal nanocluster. Its structure was characterized using single-crystal X-ray diffraction, Fourier-transform infrared spectroscopy, and powder X-ray diffraction. In addition, the charge state and chemical composition of the nanocluster were determined using electrospray ionization spectrometry and X-ray photoelectron spectroscopy (XPS) spectrum. The results of the XPS and X-ray crystallography revealed that there are two independent CuII and CuI centers in nanocluster 1 with the relative abundances of 66.6 and 33.3% for CuII and CuI, respectively. The nanocluster contains three four-coordinated CuI ions with a square-planar geometry and six five-coordinated CuII ions with a square pyramid geometry. The nanocluster shows strong near-infrared optical absorption in the solid state and excellent photothermal conversion ability (the equilibrium temperature â¼78.2 °C) with the light absorption centers in 286-917 nm over previous reported pentanucleus CuI4CuII clusters and CuII compounds.