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Inflammatory bowel disease (IBD) is a chronic disorder characterized by recurrent gastrointestinal inflammation, lacking a precise aetiology and definitive cure. The gut microbiome is vital in preventing and treating IBD due to its various physiological functions. In the interplay between the gut microbiome and human health, extracellular vesicles secreted by gut bacteria (BEVs) are key mediators. Herein, we explore the role of Roseburia intestinalis (R)-derived EVs (R-EVs) as potent anti-inflammatory mediators in treating dextran sulfate sodium-induced colitis. R was selected as an optimal BEV producer for IBD treatment through ANCOM analysis. R-EVs with a 76 nm diameter were isolated from R using a tangential flow filtration system. Orally administered R-EVs effectively accumulated in inflamed colonic tissues and increased the abundance of Bifidobacterium on microbial changes, inhibiting colonic inflammation and prompting intestinal recovery. Due to the presence of Ile-Pro-Ile in the vesicular structure, R-EVs reduced the DPP4 activity in inflamed colonic tissue and increased the active GLP-1, thereby downregulating the NFκB and STAT3 via the PI3K pathway. Our results shed light on the impact of BEVs on intestinal recovery and gut microbiome alteration in treating IBD.
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Colite , Vesículas Extracelulares , Microbioma Gastrointestinal , Vesículas Extracelulares/metabolismo , Animais , Colite/metabolismo , Colite/microbiologia , Colite/terapia , Camundongos , Inflamação/metabolismo , Sulfato de Dextrana , Humanos , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/terapia , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Camundongos Endogâmicos C57BL , Masculino , Dipeptidil Peptidase 4/metabolismo , NF-kappa B/metabolismo , Clostridiales/metabolismoRESUMO
PURPOSE: There is an abundance of online information related to bariatric surgery. Patients may prefer a specific type of bariatric surgery based on what they read online. The primary aim of this study was to determine online search trends in bariatric surgery over time in Australia and worldwide. The secondary aim was to establish a relationship between public online search activity and the types of bariatric surgery performed in Australia. MATERIALS AND METHOD: The terms "adjustable gastric band," "sleeve gastrectomy," and "gastric bypass surgery" were submitted for search volume analysis in Australia and worldwide using the Google Trends "Topic" search function. This was compared alongside the numbers of gastric bandings, sleeve gastrectomies, and gastric bypass surgeries performed in Australia over time to determine if there was a relationship between the two. RESULTS: Search trends for "adjustable gastric band" and "sleeve gastrectomy" in Australia were similar to trends seen worldwide. However, search trends for "gastric bypass surgery" differ between Australia and the rest of the world. It took at least a year for online searches to reflect the higher number of sleeve gastrectomies performed relative to gastric bandings. There was a lag time of over four years before online searches reflected the higher number of gastric bypass surgery performed compared to gastric banding. CONCLUSION: Search interests in Australia and worldwide were similar for gastric banding and sleeve gastrectomy but different for gastric bypass surgery. Online search activity did not have a significant association with the types of bariatric surgery being performed in Australia.
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Cirurgia Bariátrica , Obesidade Mórbida , Humanos , Austrália/epidemiologia , Obesidade Mórbida/cirurgia , Obesidade Mórbida/epidemiologia , Cirurgia Bariátrica/tendências , Cirurgia Bariátrica/estatística & dados numéricos , Internet , Feminino , Ferramenta de Busca/tendências , Ferramenta de Busca/estatística & dados numéricos , Gastrectomia/tendências , Gastrectomia/estatística & dados numéricos , Derivação Gástrica/tendências , Derivação Gástrica/estatística & dados numéricos , Masculino , Gastroplastia/tendências , Gastroplastia/estatística & dados numéricosRESUMO
BACKGROUND: Socioeconomic status (SES) affects outcomes following surgery for various cancers. There are currently no Australian studies that examine the role of socioeconomic disadvantage on outcomes following oesophagectomy for cancer. This study assessed whether SES was associated with short-term perioperative morbidity, long-term survival, and oncological outcomes following oesophagectomy across three tertiary oesophageal cancer centres in Australia. METHODS: A retrospective cohort study was performed comprising all patients who underwent oesophagectomy for cancer across three Australian centres. Patients were stratified into SES groups using the Index of Relative Socioeconomic Advantage and Disadvantage (IRSAD). Outcomes measured included perioperative complication rates, overall survival, and disease-free survival. RESULTS: The study cohort was 462 patients, 205 in the lower SES and 257 in the higher SES groups. The lower SES group presented with more advanced oesophageal cancer stage, a higher rate of T3 (52.6% versus 42.7%, P = 0.038) and N2 disease (19.6% versus 10.5%, P = 0.006), and had a higher rate of readmission within 30 days (11.2% versus 5.4%, P = 0.023). There was no difference in overall survival or disease-free survival between groups. CONCLUSION: Lower socioeconomic status was associated with more advanced stage and increased risk of early, unplanned readmission following oesophagectomy, but was not associated with a difference in overall or disease-free survival.
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Preconditioning-induced cerebral ischemic tolerance is known to be a beneficial adaptation to protect the brain in an unavoidable event of stroke. We currently demonstrate that a short bout (6 weeks) of intermittent fasting (IF; 15 h fast/day) induces similar ischemic tolerance to that of a longer bout (12 weeks) in adult C57BL/6 male mice subjected to transient middle cerebral artery occlusion (MCAO). In addition, the 6 weeks IF regimen induced ischemic tolerance irrespective of age (3 months or 24 months) and sex. Mice subjected to transient MCAO following IF showed improved motor function recovery (rotarod and beam walk tests) between days 1 and 14 of reperfusion and smaller infarcts (T2-MRI) on day 1 of reperfusion compared with age/sex matched ad libitum (AL) controls. Diet influences the gut microbiome composition and stroke is known to promote gut bacterial dysbiosis. We presently show that IF promotes a beneficial phenotype of gut microbiome following transient MCAO compared with AL cohort. Furthermore, post-stroke levels of short-chain fatty acids (SCFAs), which are known to be neuroprotective, are higher in the fecal samples of the IF cohort compared with the AL cohort. Thus, our studies indicate the efficacy of IF in protecting the brain after stroke, irrespective of age and sex, probably by altering gut microbiome and SCFA production.
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Ácidos Graxos Voláteis , Microbioma Gastrointestinal , Infarto da Artéria Cerebral Média , Jejum Intermitente , Animais , Feminino , Masculino , Camundongos , Isquemia Encefálica/metabolismo , Isquemia Encefálica/microbiologia , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/fisiologia , Infarto da Artéria Cerebral Média/metabolismo , Jejum Intermitente/metabolismo , Camundongos Endogâmicos C57BL , FenótipoRESUMO
INTRODUCTION: Maternal epilepsy is a critical condition that can significantly affect mothers and fetuses. Notably, the admission of a laboring mother with uncontrolled refractory status epilepticus (RSE) to the operating room presents a challenging scenario for anesthesiologists. THE MAIN SYMPTOMS OF THE PATIENT AND THE IMPORTANT CLINICAL FINDINGS: A 30-year-old primigravida was transferred to the operating room for an emergency cesarean section. Cesarean section was performed after a provisional diagnosis of preeclampsia was made. THE MAIN DIAGNOSES, THERAPEUTIC INTERVENTIONS, AND OUTCOMES: Cesarean section was performed under general anesthesia. During the postoperative period, the patient exhibited no seizure activity in the brain; however, she experienced mild cognitive dysfunction for up to 6 months postdelivery. The neonate were discharged without any complications. CONCLUSION: Inducing anesthesia in pregnant women with ongoing seizure activity are challenging; however, anesthesiologists provide judgment based on the balance between the safety of the mother and fetus and the balance between patient monitoring and the progression of anesthesia. This challenge can be addressed through multidisciplinary collaboration.
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Anestesia Geral , Cesárea , Estado Epiléptico , Humanos , Feminino , Cesárea/efeitos adversos , Adulto , Estado Epiléptico/etiologia , Gravidez , Anestesia Geral/métodos , Anestesia Geral/efeitos adversos , Complicações na Gravidez/cirurgia , Anestesia Obstétrica/métodosRESUMO
Photodynamic therapy is a noninvasive treatment in which specific photosensitizers and light are used to produce high amounts of reactive oxygen species (ROS), which can be employed for targeted tissue destruction in cancer treatment or antimicrobial therapy. However, it remains unknown whether lower amounts of ROS produced by mild photodynamic therapy increase lifespan and stress resistance at the organism level. Here, we introduce a novel photodynamic treatment (PDTr) that uses 20 µM hypericin, a photosensitizer that originates from Hypericum perforatum, and orange light (590 nm, 5.4 W/m2, 1 min) to induce intracellular ROS formation (ROS), thereby resulting in lifespan extension and improved stress resistance in C. elegans. The PDTr-induced increase in longevity was abrogated by N-acetyl cysteine, suggesting the hormetic response was driven by prooxidative mechanisms. PDTr activated the translocation of SKN-1/NRF-2 and DAF-16/FOXO, leading to elevated expression of downstream oxidative stress-responsive genes, including ctl-1, gst-4, and sod-3. In summary, our findings suggest a novel PDTr method that extends the lifespan of C. elegans under both normal and oxidative stress conditions through the activation of SKN-1 and DAF-16 via the involvement of many antioxidant genes.
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Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Longevidade , Estresse Oxidativo , Perileno , Fotoquimioterapia , Fármacos Fotossensibilizantes , Espécies Reativas de Oxigênio , Fatores de Transcrição , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Estresse Oxidativo/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Perileno/análogos & derivados , Perileno/farmacologia , Antracenos/farmacologia , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Luz , Acetilcisteína/farmacologiaRESUMO
We report two cases of total gastrectomy and Roux-en-Y reconstruction that required future endoscopic surveillance of the duodenum. As such, an additional proximal duodenojejunostomy was fashioned to facilitate endoscopic surveillance.
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Blood pressure (BP) management is important worldwide, and BP monitoring is a crucial aspect of maintaining good health. Traditional BP meter measures BP independently in various situations, such as at home or work, using a cuff to maintain a stable condition. However, these devices can causes a foreign body sensation and discomfort, and are not always practical for periodic monitoring. As a result, studies have been conducted on the use of photoplethysmography (PPG) for measuring BP. However, PPG also has limitations similar to those of traditional BP meters, as it requires the placement of sensors on two regions of the body (fingers or toes). To address this issue, researchers have conducted studies on non-contact methods for measuring BP using face and hand videos. These studies have utilized two cameras to measure PTT and have focused on internal environments, resulting in low accuracy of BP measurement in external environments. We proposes a method for robust BP measurement using pulse wave velocity (PWV) and PTT calculated from facial videos. PTT is estimated by measuring the phase difference between two different regions of interest (ROIs) and PWV is calculated using PTT and the actual distance between two ROIs. In addition, our proposed method extracts the pulse wave from the ROI to measure BP. The actual distance between the ROIs and PTT are estimated using the two extracted pulse waves, and BP is then measured using PWV and PTT. To evaluate the BP measurement performance, the BP calculated from both BP meters and facial videos (in indoor, outdoor, driving car, and flying drone environments) are compared. Our results reveal that the proposed method can robustly measure BP in diverse environments.
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BACKGROUND: The impact of sarcopenia on outcomes after esophagectomy is controversial. Most data are currently derived from Asian populations. This study aimed to correlate sarcopenia to short-term perioperative complication rates and long-term survival and recurrence outcomes. METHODS: A retrospective analysis was performed of patients undergoing esophagectomy for cancer from 3 tertiary referral centers in Australia. Sarcopenia was defined using cutoffs for skeletal muscle index (SMI), assessed on preoperative computed tomography images. Outcomes measured included complications, overall survival (OS), and disease-free survival (DFS). RESULTS: Of 462 patients (78.4% male; median age, 67 years), sarcopenia was evident in 276 (59.7%). Patients with sarcopenia had a higher rate of major (Clavien-Dindo ≥ 3b) complications (27.9% vs 14.5%; P < .001), including higher rates of postoperative cardiac arrythmia (16.3% vs 9.7%; P = .042), pneumonia requiring antibiotics (14.5% vs 9.1%; P = .008), and 30-day mortality (5.1% vs 0%; P = .002). In the sarcopenic group, the median OS was lower (37 months [95% CI, 27.1-46.9] vs 114 months [95% CI, 75.8-152.2]; P < .001), as was the median DFS (27 months [95% CI, 18.9-35.1] vs 77 months [95% CI, 36.4-117.6]; P < .001). Sarcopenia was an independent risk factor for lower survival on multivariate analysis (hazard ratio, 1.688; 95% CI, 1.223-2.329; P = .001). CONCLUSION: Patients with preoperative sarcopenia based on analysis of SMI are at a higher risk of major complications and have inferior survival and oncologic outcomes after esophagectomy for esophageal cancer.
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Neoplasias Esofágicas , Esofagectomia , Complicações Pós-Operatórias , Sarcopenia , Humanos , Sarcopenia/complicações , Sarcopenia/diagnóstico por imagem , Masculino , Esofagectomia/efeitos adversos , Feminino , Idoso , Estudos Retrospectivos , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/complicações , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Intervalo Livre de Doença , Taxa de Sobrevida , Austrália/epidemiologia , Recidiva Local de Neoplasia/epidemiologia , Pneumonia/epidemiologia , Pneumonia/etiologiaRESUMO
There has been a growing interest in skin beauty and antimelanogenic products. Melanogenesis is the process of melanin synthesis whereby melanocytes are activated by UV light or hormone stimulation to produce melanin. Melanogenesis is mediated by several enzymes, such as tyrosinase (TYR), microphthalmia-associated transcription factor (MITF), tyrosinase-related protein-1 (TRP-1), and TRP-2. In this study, we investigated the effect of Tuber himalayense extract on melanin synthesis in α-melanocyte-stimulating hormone (α-MSH)-treated B16F10 melanoma cells. We confirmed that T. himalayense extract was not toxic to α-MSH-treated B16F10 melanoma cells and exhibited a significant inhibitory effect on melanin synthesis at concentrations of 25, 50, and 100 µg/ml. Additionally, the T. himalayense extract inhibited melanin, TRP-1, TRP-2, tyrosinase, and MITF, which are enzymes involved in melanin synthesis, in a concentration-dependent manner. Furthermore, T. himalayense extract inhibited the mitogen-activated protein kinase (MAPK) pathways, such as extracellular signal-regulated kinase-1/2 (ERK), c-Jun N-terminal kinase (JNK), and p38. Therefore, we hypothesized that various components of T. himalayense extract affect multiple factors involved in melanogenesis in B16F10 cells. Our results indicate that T. himalayense extract could potentially be used as a new material for preparing whitening cosmetics.
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Melaninas , Fator de Transcrição Associado à Microftalmia , Monofenol Mono-Oxigenase , Extratos Vegetais , Melaninas/biossíntese , Melaninas/metabolismo , Animais , Camundongos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Linhagem Celular Tumoral , República da Coreia , Fator de Transcrição Associado à Microftalmia/metabolismo , Fator de Transcrição Associado à Microftalmia/genética , Oxirredutases Intramoleculares/metabolismo , alfa-MSH/farmacologia , alfa-MSH/metabolismo , Melanoma Experimental/metabolismo , Oxirredutases/metabolismo , Tubérculos/química , Glicoproteínas de Membrana/metabolismo , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Sobrevivência Celular/efeitos dos fármacosRESUMO
Most anesthetics reduce cardiac functions and lower blood pressure (BP), potentially causing excessive BP reduction in dehydrated patients or those with heart conditions, such as coronary artery disease (CAD). Considering the increased prevalence of cardiovascular disease with age, anesthesiologists must be cautious about BP reduction during general anesthesia in older adults. In the present case, a 76-year-old male patient with undiagnosed CAD in a hypovolemic state experienced a significant drop in systolic BP to the fifties during propofol and sevoflurane anesthesia. Despite the use of vasopressors, excessive hypotension persisted, leading to anesthesia suspension. Subsequent cardiac examinations, including computed tomography heart angio and calcium score, and coronary angiogram, revealed a near total occlusion of the proximal left anterior descending coronary artery (pLAD) and the formation of collateral circulation. After 5 days of hydration and anticoagulation medications and confirmation of normovolemic state, general anesthesia was attempted again and successfully induced; a normal BP was maintained throughout the surgery. Thus, it is important to conduct a thorough cardiac evaluation and maintain normovolemia for general anesthesia in older adults.
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Doença da Artéria Coronariana , Oclusão Coronária , Hipotensão , Propofol , Masculino , Humanos , Idoso , Pressão Sanguínea , Anestesia Geral/efeitos adversos , Doença da Artéria Coronariana/complicações , Anestésicos IntravenososRESUMO
Lymph node metastases are a major prognostic factor in survival of patients with oesophageal cancer. The number of lymph nodes removed during oesophagectomy has been previously proven to be associated with improved survival. The aim of this study was to examine the effect of lymph node harvest on survival specifically in pathologically node negative (pN0) patients with oesophageal cancer. Data were extracted from a prospectively populated single-surgeon database of oesophageal resections for cancer. All consecutive patients with pN0 were included. Patient-specific risk adjusted analysis of overall and disease-free survival was performed to identify the number of lymph nodes associated with improved survival. Inclusion criteria were met by 137 patients (49 squamous cell carcinoma and 88 adenocarcinoma). Adjusted for cancer stage, tumour (histological type, degree of differentiation, lympho-vascular invasion, neo-adjuvant therapy) and patient related factors (age, sex), increased lymph node number was associated with significant improvement in overall (P = 0.045) and disease free (P = 0.030) survival. Lymph node count ≥ 17 was associated with improved overall and disease-free survival. In this cohort of patients with pathologically node-negative oesophageal cancer, lymph node count of 17 or above was associated with significantly improved survival.
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Carcinoma de Células Escamosas , Neoplasias Esofágicas , Humanos , Excisão de Linfonodo , Linfonodos/cirurgia , Linfonodos/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos RetrospectivosRESUMO
Acetaminophen [Paracetamol, N-acetyl-para-aminophenol (APAP)] is a common over-the- counter analgesic agent as nonsteroidal anti-inflammatory drugs (NSAIDs). The high doses or the long-term treatment of acetaminophen via usual gavage feeding resulted in damage of testicles that presented recoverable impairment, as well as liver and kidney. The influence of acetaminophen was examined in male golden hamsters treated with acetaminophen- containing diet feeding. They were divided into 5 groups and subjected to this experiment for 4 weeks: animals housed in long photoperiod (LP) as LP control, animals housed in short photoperiod (SP) for 4 weeks as SP control (SP4), and groups of animals treated with low, middle, and high concentrations of acetaminophen (Low, Middle, High groups). Also animals housed in SP for 8 weeks were included (SP8) to contrast testicular activities, if necessary. As results, spermatozoa filled the seminiferous tubules of the testicles of animals in LP control and SP4 groups. The aspects were seen in the animals taken diets of low and middle doses of acetaminophen. The animals who fed high dose of acetaminophen showed large or small testicles. The large testicles displayed all germ cells at the steps of spermatogenesis. The small testicles presented no sperm as the animals housed in SP for 8 weeks. Thus these results indicate that acetaminophen invokes the antigonadal effects and accelerates the regressing process of the testicles in the animals compared to the animals exposed to SP.
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Due to its additional frequency response, dual-frequency ultrasound has advantages over conventional ultrasound, which operates at a specific frequency band. Moreover, a tunable frequency from a single transducer enables sonographers to achieve ultrasound images with a large detection area and high resolution. This facilitates the availability of more advanced techniques that simultaneously require low- and high-frequency ultrasounds, such as harmonic imaging and image-guided therapy. In this study, we present a novel method for dual-frequency ultrasound generation from a ferroelectric piezoelectric micromachined ultrasound transducer (PMUT). Uniformly designed transducer arrays can be used for both deep low-resolution imaging and shallow high-resolution imaging. To switch the ultrasound frequency, the only requirement is to tune a DC bias to control the polarization state of the ferroelectric film. Flextensional vibration of the PMUT membrane strongly depends on the polarization state, producing low- and high-frequency ultrasounds from a single excitation frequency. This strategy for dual-frequency ultrasounds meets the requirement for either multielectrode configurations or heterodesigned elements, which are integrated into an array. Consequently, this technique significantly reduces the design complexity of transducer arrays and their associated driving circuits.
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In this study, blended perfluorinated sulfonic acid (PFSA) ionomers with equivalent weights (EWs, g/mol) of ~1000, 980, and 830 are prepared. Catalyst layers (CLs), using blended PFSA ionomers, with different side chain lengths and EWs are investigated and compared to CLs using single ionomers. The ion exchange capacity results confirm that blended ionomers have the target EWs. As a result, blended ionomers exhibit higher ion conductivity than single ionomers at all temperatures due to the higher water uptake of the blended ionomers. This implies that blended ionomers have a bulk structure to form a competent free volume compared to single ionomers. Blended ionomers with short side chains and low EWs can help reduce the activation energy in proton conduction due to enhanced hydrophobic and hydrophilic segregation. In addition, when using the blended ionomer, the CLs form a more porous microstructure to help reduce the resistance of oxygen transport and contributes to lower mass transfer loss. This effect is proven in fuel cell operations at not a lower temperature (70 °C) and full humidification (100%) but at an elevated temperature (80 °C) and lower relative humidity (50 and 75%). Blended ionomer-based CLs with a higher water uptake and porous CL structure result in improved fuel cell performance with better mass transport than single ionomer-based CLs.
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Chlorella vulgaris (C. vulgaris) is unicellular green algae consumed worldwide as a functional food. The immune stimulatory function of C. vulgaris is known; however, no study has elucidated its immune regulatory potential and associated microbiome modulation. In the current study, we aimed to validate the immune regulatory role of C. vulgaris mediated through two mechanisms. Initially, we assessed its ability to promote the expansion of the regulatory T cell (Treg) population. Subsequently, we investigated its impact on gut microbiota composition and associated metabolites. The supplementation of C. vulgaris altered the gut microbiota composition, accompanied by increased short-chain fatty acid (SCFAs) production in mice at homeostasis. We later used C. vulgaris in the treatment of a DSS-induced colitis model. C. vulgaris intervention alleviated the pathological symptom of colitis in mice, with a corresponding increase in Treg levels. As C. vulgaris is a safe and widely used food supplement, it can be a feasible strategy to instigate cross-talk between the host immune system and the intestinal flora for the effective management of inflammatory bowel disease (IBD).
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Chlorella vulgaris , Colite , Microbioma Gastrointestinal , Microbiota , Animais , Camundongos , Linfócitos T Reguladores , Colite/induzido quimicamente , Colite/terapia , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Colo/metabolismoRESUMO
Complex nuclear magnetic resonance (NMR) signals of organic compounds containing multiple analogous substructures or mixtures pose a significant challenge to structural identification, thus resulting in frequent misassignment of structures. The GEMSTONE method, a single-scan technique that selectively excites a specific proton signal among the crowded NMR signals, was recently proposed as a solution. However, its extension to the polarization transfer method for heteronuclear spin systems was unsuccessful. Herein, we present an extension method that addresses the altered heteronuclear polarization transfer efficiency and enables the acquisition of ultraselective 13 C and 1 H-13 C correlation NMR subspectra with hertz-level signal selectivity in both dimensions. We demonstrate the effectiveness of this technique in the structural analysis of a chromopeptide pharmaceutical and a diastereomeric mixture of a fungicide.
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Heat shock protein 90 (Hsp90) is a promising anticancer target because of its chaperoning effect on multiple oncogenic proteins. The activity of Hsp90 is dependent on its ability to hydrolyze adenosine triphosphate (ATP) to adenosine diphosphate (ADP) and free phosphate. The ATPase activity of Hsp90 is linked to its chaperoning function; ATP binds to the N-terminal domain of the Hsp90, and disrupting its binding was found to be the most successful strategy in suppressing Hsp90 function. The ATPase activity can be measured by a colorimetric malachite green assay, which determines the amount of free phosphate formed by ATP hydrolysis. Here, a procedure for determining the ATPase activity of yeast Hsp90 by using the malachite green phosphate assay kit is described. Further, detailed instructions for the discovery of Hsp90 inhibitors by taking geldanamycin as an authentic inhibitor is provided. Finally, the application of this assay protocol through the high-throughput screening (HTS) of inhibitor molecules against yeast Hsp90 is discussed.
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Antineoplásicos , Proteínas de Choque Térmico HSP90 , Saccharomyces cerevisiae , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Antineoplásicos/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Chaperonas Moleculares/metabolismo , Fosfatos/metabolismo , Ligação Proteica , Saccharomyces cerevisiae/metabolismoRESUMO
In this study, two different types of ion exchange membranes are used to investigate the tendency of membrane fouling with respect to surface roughness and hydrophilicity. Commercially available membranes reinforced by electrospun nanofiber have rough and hydrophilic surfaces, and lab-made pore-filling membranes exhibit a smooth and hydrophobic surface. Three different organic surfactants (i.e., cationic, anionic and non-ionic surfactants) are chosen as foulants with similar molecular weights. It is confirmed that membrane fouling by electrical attraction mainly occurs, in which anionic and cationic foulants influence anion and cation exchange membranes, respectively. Thus, less fouling is obtained on both membranes for the non-charged foulant. The membranes with a rough surface show a higher fouling tendency than those with a smooth surface in the short-term continuous fouling tests. However, during the cyclic operations of fouling and mitigation of the commercially available membranes, the irregularities of a rough membrane surface cause a rapid increase in electrical resistance from the beginning of fouling due to excessive adsorption on the surface, but the fouling is easily mitigated due to the hydrophilic surface. On the other hand, the membranes with a smooth surface show alleviated fouling from the beginning of fouling, but the irreversible fouling occurs as foulants accumulate on the hydrophobic surface which causes membrane fouling to be favorable.