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1.
Hum Brain Mapp ; 45(4): e26633, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38433682

RESUMEN

Most neuroimaging studies linking regional brain volumes with cognition correct for total intracranial volume (ICV), but methods used for this correction differ across studies. It is unknown whether different ICV correction methods yield consistent results. Using a brain-wide association approach in the MRI substudy of UK Biobank (N = 41,964; mean age = 64.5 years), we used regression models to estimate the associations of 58 regional brain volumetric measures with eight cognitive outcomes, comparing no correction and four ICV correction approaches. Approaches evaluated included: no correction; dividing regional volumes by ICV (proportional approach); including ICV as a covariate in the regression (adjustment approach); and regressing the regional volumes against ICV in different normative samples and using calculated residuals to determine associations (residual approach). We used Spearman-rank correlations and two consistency measures to quantify the extent to which associations were inconsistent across ICV correction approaches for each possible brain region and cognitive outcome pair across 2320 regression models. When the association between brain volume and cognitive performance was close to null, all approaches produced similar estimates close to the null. When associations between a regional volume and cognitive test were not null, the adjustment and residual approaches typically produced similar estimates, but these estimates were inconsistent with results from the crude and proportional approaches. For example, when using the crude approach, an increase of 0.114 (95% confidence interval [CI]: 0.103-0.125) in fluid intelligence was associated with each unit increase in hippocampal volume. However, when using the adjustment approach, the increase was 0.055 (95% CI: 0.043-0.068), while the proportional approach showed a decrease of -0.025 (95% CI: -0.035 to -0.014). Different commonly used methods to correct for ICV yielded inconsistent results. The proportional method diverges notably from other methods and results were sometimes biologically implausible. A simple regression adjustment for ICV produced biologically plausible associations.


Asunto(s)
Encéfalo , Cognición , Humanos , Persona de Mediana Edad , Encéfalo/diagnóstico por imagen , Hipocampo , Inteligencia , Neuroimagen
2.
Prev Med ; 184: 107994, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38723779

RESUMEN

BACKGROUND: The potential health effects of taxing sugar-sweetened beverages (SSBs) has been insufficiently examined in Asian contexts. This study aimed to assess the impact of SSB taxation on the prevalence of obesity/overweight and type 2 diabetes mellitus (T2DM) in Hong Kong using a willingness-to-pay (WTP) survey and simulation analysis. METHODS: A random telephone survey was conducted with 1000 adults from May to June 2020. We used a contingent valuation approach to assess individuals' WTP for SSBs under four tax payment scenarios (5%, 10%, 40%, and 50% of the current market price). Based on the WTP, a simulation analysis was conducted to project changes in SSB purchase and associated reductions in the prevalence of obesity/overweight and T2DM over a 10-year simulation period. FINDINGS: When 5% and 10% taxation rates were introduced, approximately one-third of the population were unwilling to maintain their SSB purchase. Our simulation demonstrated a gradual decline in the prevalence of obesity/overweight and diabetes with a more pronounced decrease when higher taxation rates were introduced. 10% taxation resulted in a mean reduction of 1532.7 cases of overweight/obesity per 100 thousand population at the sixth year, while T2DM prevalence decreased by 267.1 (0.3%). CONCLUSIONS: This study underscores the effects of an SSB tax on purchase behaviors and health outcomes in an affluent Asia setting, with a more pronounced influence on adult population. These findings are expected to inform policymakers in making decisions regarding an effective and equitable tax rate on SSBs.


Asunto(s)
Diabetes Mellitus Tipo 2 , Obesidad , Sobrepeso , Bebidas Azucaradas , Impuestos , Humanos , Diabetes Mellitus Tipo 2/epidemiología , Bebidas Azucaradas/economía , Bebidas Azucaradas/estadística & datos numéricos , Masculino , Femenino , Obesidad/epidemiología , Adulto , Sobrepeso/epidemiología , Persona de Mediana Edad , Hong Kong/epidemiología , Prevalencia , Encuestas y Cuestionarios
3.
Surg Endosc ; 38(4): 2106-2115, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38438672

RESUMEN

BACKGROUND: This study aimed to compare postoperative complications in patients with esophagogastric variceal bleeding (EVB) who underwent laparoscopic splenectomy combined with pericardial devascularization (LSPD) versus transjugular intrahepatic portosystemic shunt (TIPS) procedures. METHODS: A retrospective collection of medical records was conducted from January 2014 to May 2020 at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. The study included patients from the departments of trauma surgery, interventional radiology, and general surgery who were diagnosed with EVB caused by portal hypertension and treated with LSPD or TIPS. Follow-up data were obtained to assess the occurrence of postoperative complications in both groups. RESULTS: A total of 201 patients were included in the study, with 104 cases in the LSPD group and 97 cases in the TIPS group. There was no significant difference in the 1-year and 3-year post-surgery survival rates between the TIPS and LSPD groups (P = 0.669, 0.066). The 3-year survival rate of Child-Pugh B patients in the LSPD group was higher than TIPS group (P = 0.041). The LSPD group also had a significantly higher rate of freedom from rebleeding at 3-year post-surgery compared to the TIPS group (P = 0.038). Stratified analysis showed no statistically significant difference in the rebleeding rate between the two groups. Furthermore, the LSPD group had a higher rate of freedom from overt hepatic encephalopathy at 1-year and 3-year post-surgery compared to the TIPS group (P = 0.007, < 0.001). The LSPD group also had a lower rate of severe complications at 3-year post-surgery compared to the TIPS group (P = 0.020). CONCLUSION: Compared to TIPS, LSPD does not increase the risk of mortality and rebleeding, while demonstrating fewer complications. In patients classified as Child-Pugh A and B, the use of LSPD for treating EVB is both safe and effective.


Asunto(s)
Várices Esofágicas y Gástricas , Laparoscopía , Derivación Portosistémica Intrahepática Transyugular , Humanos , Várices Esofágicas y Gástricas/complicaciones , Várices Esofágicas y Gástricas/cirugía , Derivación Portosistémica Intrahepática Transyugular/efectos adversos , Esplenectomía/efectos adversos , Estudios Retrospectivos , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/cirugía , Cirrosis Hepática/cirugía , Laparoscopía/efectos adversos , Pronóstico , Resultado del Tratamiento , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
4.
Artículo en Inglés | MEDLINE | ID: mdl-38430152

RESUMEN

Objective: This case report aims to present a rare case of thoracic lordosis and lumbar kyphosis and describe the posterior instrumented scoliosis correction performed. Case presentation: A 59-year-old female presented with low back pain. She had undergone ventriculoperitoneal shunt placement 8 years ago. I scored 76 on the Wechsler Adult Intelligence Scale. MRI of the lumbar spine showed spinal canal stenosis at L3/4, L4/5, and L5/S1. Full spine X-ray revealed thoracic lordosis and lumbar kyphoscoliosis, the coronal imbalance, and the sagittal compensatory balance. In order to avoid the risk of brain swelling and paraplegia, pedicle subtraction osteotomies (PSO) in the L2 and lumbar posterior instrumented scoliosis correction were performed under electroencephalogram and neuro electrophysiological monitoring. Shoulder imbalance was observed 1 year after surgery, but there was no loss of lumbar correction. Conclusion: In future cases of complex spinal deformity, it is important to observe whether there is cerebral ventricular dilatation on MRI before the operation. If severe thoracic lordosis is combined with lumbar scoliosis, over-correcting the lumbar scoliosis should be avoided to prevent shoulder imbalance.

5.
Alzheimers Dement ; 20(2): 1149-1155, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37904290

RESUMEN

INTRODUCTION: The results of the CLARITY-AD, GRADUATE I and II, and TRAILBLAZER-ALZ 2 trials have rekindled discussion on the impact of amyloid-targeting drugs. We use a Bayesian approach to quantify how rational observers would have updated their prior beliefs based on new trial results. METHODS: We used publicly available data from the CLARITY-AD, GRADUATE I and II, and TRAILBLAZER-ALZ 2 trials to estimate the effect of reducing amyloid on the clinical dementia rating scale, sum of boxes (CDR-SB) score. A range of prior positions were then updated according to Bayes' theorem using these estimates. RESULTS: After updating with new trial data, a wide range of starting positions resulted in credible intervals that did not include no effect of amyloid reduction on CDR-SB score. DISCUSSION: For a range of starting beliefs and assuming the veracity of the underlying data, rational observers would conclude there is a small benefit of amyloid reductions on cognition. This benefit must be weighed against opportunity cost and side-effect risk. HIGHLIGHTS: The results of recent trials of amyloid-targeting drugs have rekindled discussion on the impact of amyloid reductions achieved with amyloid-targeting drugs on cognition. Prior to the announcement of trial results, beliefs about the effects of altering amyloid levels varied. For a range of starting beliefs, one would conclude there is a small benefit of amyloid reductions due to amyloid-targeting drugs on cognition. The perceived value of individual drugs must balance the magnitude of this benefit against opportunity cost and risk of side effects.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Teorema de Bayes , Pruebas de Estado Mental y Demencia , Proteínas Amiloidogénicas , Cognición , Péptidos beta-Amiloides
6.
Alzheimers Dement ; 20(2): 880-889, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37811979

RESUMEN

INTRODUCTION: Cancer survivors are less likely than comparably aged individuals without a cancer history to develop Alzheimer's disease and related dementias (ADRD). METHODS: In the UK Biobank, we investigated associations between cancer history and five structural magnetic resonance imaging (MRI) markers for ADRD risk, using linear mixed-effects models to assess differences in mean values and quantile regression to examine whether associations varied across the distribution of MRI markers. RESULTS: Cancer history was associated with smaller mean hippocampal volume (b = -19 mm3 , 95% CI = -36, -1) and lower mean cortical thickness in the Alzheimer's disease signature region (b = -0.004 mm, 95% CI = -0.007, -0.000). Quantile regressions indicated individuals most vulnerable to ADRD were more affected by cancer history. DISCUSSION: Some brain MRI markers associated with ADRD risk were elevated in adults with a history of cancer. The magnitude of the adverse associations varied across quantiles of neuroimaging markers, and the pattern suggests possible harmful associations for individuals already at high ADRD risk. HIGHLIGHTS: We found no evidence of an inverse association between cancer history and ADRD-related neurodegeneration. Cancer history was associated with smaller mean hippocampal volume and lower mean cortical thickness in the Alzheimer's disease signature region. Quantile regressions indicated individuals most vulnerable to ADRD were more affected by cancer history.


Asunto(s)
Enfermedad de Alzheimer , Demencia , Neoplasias , Humanos , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Demencia/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Envejecimiento , Neoplasias/diagnóstico por imagen
7.
Alzheimers Dement ; 20(3): 1978-1987, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38183377

RESUMEN

INTRODUCTION: We estimated the ages when associations between Alzheimer's disease (AD) genes and brain volumes begin among middle-aged and older adults. METHODS: Among 45,616 dementia-free participants aged 45-80, linear regressions tested whether genetic risk score for AD (AD-GRS) had age-dependent associations with 38 regional brain magnetic resonance imaging volumes. Models were adjusted for sex, assessment center, genetic ancestry, and intracranial volume. RESULTS: AD-GRS modified the estimated effect of age (per decade) on the amygdala (-0.41 mm3 [-0.42, -0.40]); hippocampus (-0.45 mm3 [-0.45, -0.44]), nucleus accumbens (-0.55 mm3 [-0.56, -0.54]), thalamus (-0.38 mm3 [-0.39, -0.37]), and medial orbitofrontal cortex (-0.23 mm3 [-0.24, -0.22]). Trends began by age 45 for the nucleus accumbens and thalamus, 48 for the hippocampus, 51 for the amygdala, and 53 for the medial orbitofrontal cortex. An AD-GRS excluding apolipoprotein E (APOE) was additionally associated with entorhinal and middle temporal cortices. DISCUSSION: APOE and other genes that increase AD risk predict lower hippocampal and other brain volumes by middle age.


Asunto(s)
Enfermedad de Alzheimer , Persona de Mediana Edad , Humanos , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/complicaciones , Puntuación de Riesgo Genético , Bancos de Muestras Biológicas , Biobanco del Reino Unido , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Apolipoproteínas E/genética , Imagen por Resonancia Magnética
8.
Br J Cancer ; 129(4): 648-655, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37402868

RESUMEN

BACKGROUND: The objective of this study was to evaluate associations of diabetes overall, type 1 diabetes (T1D), and type 2 diabetes (T2D) with breast cancer (BCa) risk. METHODS: We included 250,312 women aged 40-69 years between 2006 and 2010 from the UK Biobank cohort. Adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) were calculated for associations of diabetes and its two major types with the time from enrollment to incident BCa. RESULTS: We identified 8182 BCa cases during a median follow-up of 11.1 years. We found no overall association between diabetes and BCa risk (aHR = 1.02, 95% CI = 0.92-1.14). When accounting for diabetes subtype, women with T1D had a higher risk of BCa than women without diabetes (aHR = 1.52, 95% CI = 1.03-2.23). T2D was not associated with BCa risk overall (aHR = 1.00, 95% CI = 0.90-1.12). However, there was a significantly increased risk of BCa in the short time window after T2D diagnosis. CONCLUSIONS: Though we did not find an association between diabetes and BCa risk overall, an increased risk of BCa was observed shortly after T2D diagnosis. In addition, our data suggest that women with T1D may have an increased risk of BCa.


Asunto(s)
Neoplasias de la Mama , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Humanos , Femenino , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 1/complicaciones , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/complicaciones , Estudios Prospectivos , Factores de Riesgo
9.
Neurochem Res ; 48(3): 767-780, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36418652

RESUMEN

Spinal cord injury (SCI) is a serious injury to the central nervous system that causes significant physical and psychological trauma to the patient. SCI includes primary spinal cord injuries and secondary spinal cord injuries. The secondary injury refers to the pathological process or reaction after the primary injury. Although SCI has always been thought to be an incurable injury, the human nerve has the ability to repair itself after an injury. However, the reparability is limited because glial scar formation impedes functional recovery. There is a type of astrocyte that can differentiate into two forms of reactive astrocytes known as 'A1' and 'A2' astrocytes. A1 astrocytes release cytotoxic chemicals that cause neurons and oligodendrocytes to die and perform a harmful role. A2 astrocytes can produce neurotrophic factors and act as neuroprotectors. This article discusses ways to block A1 astrocytes while stimulating A2 astrocytes to formulate a new treatment for spinal cord injury.


Asunto(s)
Astrocitos , Traumatismos de la Médula Espinal , Humanos , Astrocitos/patología , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/patología , Neuronas/patología , Gliosis/patología , Sistema Nervioso Central , Médula Espinal/patología
10.
PLoS Comput Biol ; 18(6): e1010281, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35759509

RESUMEN

In the context of infectious disease transmission, high heterogeneity in individual infectiousness indicates that a few index cases can generate large numbers of secondary cases, a phenomenon commonly known as superspreading. The potential of disease superspreading can be characterized by describing the distribution of secondary cases (of each seed case) as a negative binomial (NB) distribution with the dispersion parameter, k. Based on the feature of NB distribution, there must be a proportion of individuals with individual reproduction number of almost 0, which appears restricted and unrealistic. To overcome this limitation, we generalized the compound structure of a Poisson rate and included an additional parameter, and divided the reproduction number into independent and additive fixed and variable components. Then, the secondary cases followed a Delaporte distribution. We demonstrated that the Delaporte distribution was important for understanding the characteristics of disease transmission, which generated new insights distinct from the NB model. By using real-world dataset, the Delaporte distribution provides improvements in describing the distributions of COVID-19 and SARS cases compared to the NB distribution. The model selection yielded increasing statistical power with larger sample sizes as well as conservative type I error in detecting the improvement in fitting with the likelihood ratio (LR) test. Numerical simulation revealed that the control strategy-making process may benefit from monitoring the transmission characteristics under the Delaporte framework. Our findings highlighted that for the COVID-19 pandemic, population-wide interventions may control disease transmission on a general scale before recommending the high-risk-specific control strategies.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , COVID-19/epidemiología , Enfermedades Transmisibles/epidemiología , Humanos , Funciones de Verosimilitud , Modelos Estadísticos , Pandemias/prevención & control
11.
Eur J Epidemiol ; 38(10): 1069-1079, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37634228

RESUMEN

Epidemiological studies have identified an inverse association between cancer and dementia. Underlying methodological biases have been postulated, yet no studies have systematically investigated the potential for each source of bias within a single dataset. We used the UK Biobank to compare estimates for the cancer-dementia association using different analytical specifications designed to sequentially address multiple sources of bias, including competing risk of death, selective survival, confounding bias, and diagnostic bias. We included 140,959 UK Biobank participants aged ≥ 55 without dementia before enrollment and with linked primary care data. We used cancer registry data to identify cancer cases prevalent before UK Biobank enrollment and incident cancer diagnosed after enrollment. We used Cox models to evaluate associations of prevalent and incident cancer with all-cause dementia, Alzheimer's disease (AD), and vascular dementia. We used time-varying models to evaluate diagnostic bias. Over a median follow-up of 12.3 years, 3,310 dementia cases were diagnosed. All-site incident cancer was positively associated with all-cause dementia incidence (hazard ratio [HR] = 1.14, 95% CI: 1.02-1.29), but prevalent cancer was not (HR = 1.04, 95% CI: 0.92-1.17). Results were similar for vascular dementia. AD was not associated with prevalent or incident cancer. Dementia diagnosis was substantially elevated in the first year after cancer diagnosis (HR = 1.83, 95% CI: 1.42-2.36), after which the association attenuated to null, suggesting diagnostic bias. Following a cancer diagnosis, health care utilization or cognitive consequences of diagnosis or treatment may increase chance of receiving a dementia diagnosis, creating potential diagnostic bias in electronic health records-based studies.


Asunto(s)
Enfermedad de Alzheimer , Demencia Vascular , Demencia , Neoplasias , Humanos , Demencia/diagnóstico , Demencia Vascular/diagnóstico , Demencia Vascular/epidemiología , Demencia Vascular/etiología , Bancos de Muestras Biológicas , Biobanco del Reino Unido , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/diagnóstico , Neoplasias/epidemiología , Neoplasias/etiología
12.
J Integr Neurosci ; 22(2): 42, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36992585

RESUMEN

OBJECTIVES: Intracranial hemorrhage is the second most common stroke subtype following ischemic stroke and usually induces high mortality and disability. Here, we conducted a retrospective study to establish a nomogram clinical prediction model. METHODS: First, the baseline data of patients who presented to our hospital in 2015-2021 were collected and compared (789 patients for the training cohort and 378 patients for the validation cohort). Second, univariate and binary logistic analyses were performed to screen out alternative indicators. Finally, a clinical prediction model by nomogram was established that included such indicators to estimate the prognosis of intracranial hemorrhage patients. RESULTS: Univariate logistic analysis was used to screen several possible impact factors, including hypertension, hematoma volume, Glasgow Coma Scale (GCS) score, intracranial hemorrhage (ICH) score, irregular shape, uneven density, intraventricular hemorrhage (IVH) relation, fibrinogen, D-dimer, low density lipoprotein (LDL), high-density lipoprotein (HDL), creatinine, total protein, hemoglobin (HB), white blood cell (WBC), neutrophil blood cell (NBC), lymphocyte blood cell (LBC), the neutrophil lymphocyte ratio (NLR), surgery, deep venous thrombosis (DVT) or pulmonary embolism (PE) rate, hospital day, and hypertension control. Further binary logistic analysis revealed that ICH score (p = 0.036), GCS score (p = 0.000), irregular shape (p = 0.000), uneven density (p = 0.002), IVH relation (p = 0.014), surgery (p = 0.000) were independent indicators to construct a nomogram clinical prediction model. The C statistic was 0.840. CONCLUSIONS: ICH score, GCS score, irregular shape, uneven density, IVH relation, surgery are easily available indicators to assist neurologists in formulating the most appropriate therapy for every intracranial hemorrhage patient. Further large prospective clinical trials are needed to obtain more integrated and reliable conclusions.


Asunto(s)
Hipertensión , Nomogramas , Humanos , Pronóstico , Estudios Retrospectivos , Estudios Prospectivos , Modelos Estadísticos , Hemorragia Cerebral , Hemorragias Intracraneales
13.
Alzheimers Dement ; 19(9): 4028-4036, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37199336

RESUMEN

INTRODUCTION: The challenge of accounting for practice effects (PEs) when modeling cognitive change was amplified by the COVID-19 pandemic, which introduced period and mode effects that may bias the estimation of cognitive trajectory. METHODS: In three Kaiser Permanente Northern California prospective cohorts, we compared predicted cognitive trajectories and the association of grip strength with cognitive decline using three approaches: (1) no acknowledgment of PE, (2) inclusion of a wave indicator, and (3) constraining PE based on a preliminary model (APM) fit using a subset of the data. RESULTS: APM-based correction for PEs based on balanced, pre-pandemic data, and with current age as the timescale produced the smallest discrepancy between within-person and between-person estimated age effects. Estimated associations between grip strength and cognitive decline were not sensitive to the approach used. DISCUSSION: Constraining PEs based on a preliminary model is a flexible, pragmatic approach allowing for meaningful interpretation of cognitive change. HIGHLIGHTS: The magnitude of practice effects (PEs) varied widely by study. When PEs were present, the three PE approaches resulted in divergent estimated age-related cognitive trajectories. Estimated age-related cognitive trajectories were sometimes implausible in models that did not account for PEs. The associations between grip strength and cognitive decline did not differ by the PE approach used. Constraining PEs based on estimates from a preliminary model allows for a meaningful interpretation of cognitive change.


Asunto(s)
COVID-19 , Envejecimiento Cognitivo , Humanos , Envejecimiento/psicología , Pandemias , Estudios Prospectivos , Estudios Longitudinales
14.
Molecules ; 28(2)2023 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-36677896

RESUMEN

Self-assembled fibrillation of wheat gluten is a common phenomenon in the daily production and processing of wheat flour products. The driving forces for its formation and the factors that influence the morphology of fibrils have not been thoroughly investigated. In this study, the effect of three bonding changes (breaking hydrogen bonds, strengthening hydrophobic interactions, and SH-SS exchange reactions) on gluten polypeptide (GP) fibrillation was simulated by adjusting the heating temperature (room temperature (RT), 45 °C, 65 °C, and 95 °C). The results showed that the breakage of hydrogen bonds could induce conformational transitions in GPs and help to excite fibrillation in GPs. Strengthened hydrophobic interactions significantly contributed to the fibrillation of GPs. Covalent crosslinks generated by SH-SS exchange reactions might also promote the fibrillation of GPs. GPs with different degrees of hydrolysis (4.0%, 6.0%, and 10.0%, represented by DH 4, DH 6, and DH 10, respectively) presented different extents of fibrillation, with DH 10 GPs having a higher propensity to fibrillation than DH 4 and DH 6 GPs. The results of Fourier's transform infrared spectroscopy indicated that hydrophobic interactions drive the transition from a random coil and α-helix to a ß-sheet. In addition, hydrophobic interactions also drive the intermolecular polymerization of GPs, resulting in larger molecular weight aggregates. The morphology presented by transmission electron microscopy showed that the greater the DH, the stronger the tendency for the worm-like aggregation of GPs.


Asunto(s)
Harina , Triticum , Triticum/química , Harina/análisis , Glútenes/química , Péptidos , Temperatura
15.
Molecules ; 28(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37446762

RESUMEN

We optimized an ultrasound-assisted extraction process of Phellinus linteus mycelium polysaccharides (PLPs) and studied their monosaccharide composition and bacteriostatic properties. Based on a single-factor experiment, a three-factor, three-level Box-Behnken design was used to optimize the ultrasound-assisted extraction process of PLP, using the yield of PLP as the index. The chemical composition and monosaccharide composition of PLP were determined by chemical analysis and HPLC analysis, respectively. Microscopic morphological analysis of the surface of PLP was performed via swept-surface electron microscopy. The bacteriostatic properties of PLP were determined using the spectrophotometric turbidimetric method. The results showed that the best extraction process of PLP with ultrasonic assistance achieved a result of 1:42 g/mL. In this method, the ultrasonic temperature was 60 °C, ultrasonic extraction was performed for 20 min, and the yield of PLP was 12.98%. The monosaccharide composition of PLP mainly contains glucose (Glc), mannose (Man), galactose (Gal), and glucuronic acid (GlcA). The intracellular polysaccharide of Phellinus igniarius Mycelia (PIP) is an irregular spherical accumulation, the surface is rough and not smooth, and the extracellular polysaccharide (PEP) is a crumbly accumulation. PIP has a stronger inhibitory ability for S. aureus and E. coli and a slightly weaker inhibitory effect for B. subtilis; the inhibitory effect of PEP on S. aureus, E. coli, and B. subtilis is slightly inferior to that of PIP.


Asunto(s)
Escherichia coli , Staphylococcus aureus , Humanos , Polisacáridos/farmacología , Polisacáridos/química , Monosacáridos
16.
Arch Toxicol ; 96(5): 1473-1482, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35224661

RESUMEN

Conjugated bile acids are synthesized in liver and subsequently secreted into the intestinal lumen from which they are actively reabsorbed and transported back to liver. The efficient enterohepatic circulation of conjugated bile acids is important to maintain homeostasis. The mycotoxin deoxynivalenol (DON) is a fungal secondary metabolite that contaminates cereal food. Upon human exposure, it can cause intestinal dysfunction. We explored the effects of DON exposure on the intestinal absorption of conjugated bile acids and the expression of bile acid transporters using an in vitro model based on Caco-2 cell layers grown in transwells. Our study shows that the transport rate of taurocholic acid (TCA) is decreased after 48-h pre-exposure of the Caco-2 cells to 2 µM DON, which is a realistic intestinal DON concentration. Exposure to DON downregulates expression of the genes coding for the apical sodium-dependent bile acid transporter (ASBT), the ileal bile acid-binding protein (IBABP) and the organic solute transporter α (OSTα), and it counteracts the agonist activity of Farnesoid X receptor (FXR) agonist GW4064 on these genes. In addition, the transport of ten taurine or glycine-conjugated bile acids in a physiological relevant mixture by the intestinal Caco-2 cell layers was decreased after pre-exposure of the cells to DON, pointing at a potential for DON-mediated accumulation of the conjugated bile acids at the intestinal luminal side. Together the results reveal that DON inhibits intestinal bile acid reabsorption by reducing the expression of bile acid transporters thereby affecting bile acid intestinal kinetics, leading to bile acid malabsorption in the intestine. Our study provides new insights into the hazards of DON exposure.


Asunto(s)
Micotoxinas , Ácidos y Sales Biliares , Células CACO-2 , Humanos , Intestinos , Micotoxinas/farmacología , Tricotecenos
17.
Arch Toxicol ; 96(12): 3291-3303, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36074177

RESUMEN

Bile acid homeostasis plays an important role in many biological activities through the bile-liver-gut axis. In this study, two in vitro models were applied to further elucidate the mode of action underlying reported in vivo bile acid changes induced by antibiotics (colistin sulfate, tobramycin, meropenem trihydrate, and doripenem hydrate). 16S rRNA analysis of rat fecal samples anaerobically incubated with these antibiotics showed that especially tobramycin induced changes in the gut microbiota. Furthermore, tobramycin was shown to inhibit the microbial deconjugation of taurocholic acid (TCA) and the transport of TCA over an in vitro Caco-2 cell layer used as a model to mimic intestinal bile acid reuptake. The effects induced by the antibiotics in the in vitro model systems provide novel and complementary insight explaining the effects of the antibiotics on microbiota and fecal bile acid levels upon 28-day in vivo treatment of rats. In particular, our results provide insight in the mode(s) of action underlying the increased levels of TCA in the feces upon tobramycin exposure. Altogether, the results of the present study provide a proof-of-principle on how in vitro models can be used to elucidate in vivo effects on bile acid homeostasis, and to obtain insight in the mode(s) of action underlying the effect of an antibiotic, in this case tobramycin, on bile acid homeostasis via effects on intestinal bile acid metabolism and reuptake.


Asunto(s)
Antibacterianos , Ácidos y Sales Biliares , Humanos , Ratas , Animales , ARN Ribosómico 16S , Antibacterianos/toxicidad , Colistina , Meropenem , Doripenem , Células CACO-2 , Ácido Taurocólico , Tobramicina/farmacología
18.
Mar Drugs ; 20(4)2022 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-35447942

RESUMEN

Hahella is one characteristic genus under the Hahellaceae family and shows a good potential for synthesizing new natural products. In this study, we examined the distribution of the secondary metabolite biosynthetic gene cluster (SMBGC) under Hahella with anti-SMASH. The results derived from five genomes released 70 SMBGCs. On average, each strain contains 12 gene clusters, and the most abundant ones (45.7%) are from the family of non-ribosomal peptide synthetase (NRPS) and non-ribosomal peptide synthetase hybrid with polyketide synthase (NRPS/PKS), indicating a great potential to find bioactive compounds. The comparison of SMBGC between H. chejuensis and other species showed that H. chejuensis contained two times more gene clusters than H. ganghwensis. One strain, designed as NBU794, was isolated from the mangrove soil of Dongzhai Port in Haikou (China) by iChip. The 16S rRNA gene of NBU794 exhibited 99% identity to H. chejuensis KCTC 2396 and clustered with the H. chejuensis clade on the phylogenetic trees. Genome mining on strain NBU794 released 17 SMBGCs and two groups of bioactive compounds, which are chejuenolide A-C and nine prodiginines derivatives. The prodiginines derivatives include the well-known lead compound prodigiosin and two new compounds, 2-methyl-3-pentyl-4-O-methyl-prodiginine and 2-methyl-3-octyl-prodiginine, which were identified through fragmentation analysis based on LC-MS/MS. The anti-microbial activity assay showed prodigiosin and 2-methyl-3-heptyl-prodiginine exhibited the best performance in inhibiting Escherichia coli, Salmonella paratyphi B, MASA Staphylococcus aureus, Bacillus subtilis, and Candida albicans. Moreover, the yield of prodigiosin in H. chejuensis NBU794 was also evaluated, which could reach 1.40 g/L under the non-optimized condition and increase to 5.83 g/L in the modified ISP4 medium with macroporous adsorption beads added, indicating that NBU794 is a promising source of prodigiosin.


Asunto(s)
Gammaproteobacteria , Prodigiosina , Cromatografía Liquida , Escherichia coli/metabolismo , Filogenia , Prodigiosina/farmacología , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Espectrometría de Masas en Tándem
19.
Clin Gastroenterol Hepatol ; 19(5): 955-966.e61, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32088300

RESUMEN

BACKGROUND & AIMS: We studied incidence and mortality trends of colorectal cancer (CRC) in 39 countries according to age, sex, and anatomic location (colon vs rectum). METHODS: We retrieved incidence data from registries from 36 countries. The registries included the following: Cancer Incidence in 5 Continents volumes I to XI; the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute; and the Nordic Cancer Registries from Europe. We obtained mortality data from 39 countries of the World Health Organization database. We evaluated average annual percentage changes in CRC incidence and mortality in the past decade using joinpoint regression analysis. RESULTS: From 2007 to 2016, 2006 to 2015, or 2005 to 2014, depending on the availability of the data, the incidence of colon cancer increased in 10 of 36 countries analyzed (all in Asia or Europe); India had the greatest increase, followed by Poland. All 10 of these countries have medium to high Human Development Index (HDI) scores. Six countries had a decrease in colon cancer incidence; these countries had the highest HDI scores; the United States had the greatest decrease, followed by Israel. Seven countries (including all countries from Northern America) had a decrease in incidence among persons older than 50 years. Eight countries had an increase in colon cancer incidence among persons younger than 50 years, including the United Kingdom and India. Countries with a decreased or stable incidence among persons 50 years or older but a significant increase in persons younger than 50 years, included Germany, Australia, the United States, Sweden, Canada, and the United Kingdom. Only Italy had a decrease in CRC incidence among persons younger than 50 years. Among women, 12 of 36 countries (all from Asia and Europe) had an increase in colon cancer incidence and 7 countries had a decrease; India had the greatest increase followed by Slovenia. Five of 36 countries had an increase in incidence of rectal cancer and 8 countries had a decrease; Ecuador and Thailand had the greatest increases in incidence. The incidence of rectal cancer among persons younger than 50 years increased significantly in Finland, Australia, Canada, the United States, and The Netherlands. Four countries had an increase in the incidence of rectal cancer in women; Ecuador had the greatest increase followed by Thailand. The incidence of rectal cancer in women decreased in 8 countries. Among women younger than 50 years, rectal cancer incidence increased, despite a decrease in women older than 50 years, in Costa Rica, Slovenia, Japan, Slovakia, Canada, and the United States there was an increase in incidence, although their elder population had a stable or decreased incidence. Twenty-four countries reported a reduction in CRC mortality, including North America, Oceania, and most European countries. Nevertheless, some countries from Asia, Latin America, and Southern Europe had significant increases in CRC mortality. CONCLUSIONS: In an analysis of incidence and mortality databases from 39 countries, we found that the incidence of colon and rectal cancers has continued to increase in countries with medium to high HDI and in younger populations. Preventive strategies are needed for countries with increasing CRC and rectal cancer incidence and mortality.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias del Recto , Anciano , Asia/epidemiología , Neoplasias Colorrectales/epidemiología , Europa (Continente)/epidemiología , Femenino , Humanos , Incidencia , Sistema de Registros , Estados Unidos/epidemiología
20.
Cancer Immunol Immunother ; 70(10): 2893-2909, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33688997

RESUMEN

This work investigated the clinical prognostic implications and biological function of plasma soluble programmed cell death ligand 1 in breast cancer patients. Plasma sPD-L1 levels of recurrent/metastatic breast cancer patients were determined, and the association of sPD-L1 levels and metastatic progression-free survival and metastatic overall survival was assessed. The PD-L1 expression on breast cancer cells was analyzed by flow cytometry, and the level of sPD-L1 in the supernatant of breast cancer cells was determined by enzyme-linked immunosorbent assay. Furthermore, the effect of sPD-L1 on the proliferation and apoptosis of T lymphocytes was detected by WST-1 assay and flow cytometry. The plasma sPD-L1 levels in 208 patients with recurrent/metastatic breast cancer before receiving first-line rescue therapy were measured. The optimal cutoff value of plasma sPD-L1 for predicting disease progression was 8.774 ng/ml. Univariate and multivariate analyses identified high sPD-L1 level (≥ 8.774 ng/ml) and visceral metastasis were independent factors associated with poor prognosis. Relevance analysis showed that the plasma sPD-L1 level was weaklyassociated with some systemic inflammation markers, including white cell count (WBC), absolute monocytecount, and absolute neutrophil count. Furthermore, we found sPD-L1 could be found in supernatant of culture with breast cancer cell line expressing PD-L1 on the cell surface and inhibit T lymphocyte function, playing a negative regulatory role in cellular immunity. sPD-L1 was a good tumor predictive maker in breast cancer and it may play a potentially important role in immune tolerance.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Linfocitos T/metabolismo , Neoplasias de la Mama/mortalidad , Línea Celular Tumoral , Femenino , Humanos , Persona de Mediana Edad , Supervivencia sin Progresión
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