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1.
Cell ; 180(2): 278-295.e23, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31978345

RESUMO

Mutations in FAMIN cause arthritis and inflammatory bowel disease in early childhood, and a common genetic variant increases the risk for Crohn's disease and leprosy. We developed an unbiased liquid chromatography-mass spectrometry screen for enzymatic activity of this orphan protein. We report that FAMIN phosphorolytically cleaves adenosine into adenine and ribose-1-phosphate. Such activity was considered absent from eukaryotic metabolism. FAMIN and its prokaryotic orthologs additionally have adenosine deaminase, purine nucleoside phosphorylase, and S-methyl-5'-thioadenosine phosphorylase activity, hence, combine activities of the namesake enzymes of central purine metabolism. FAMIN enables in macrophages a purine nucleotide cycle (PNC) between adenosine and inosine monophosphate and adenylosuccinate, which consumes aspartate and releases fumarate in a manner involving fatty acid oxidation and ATP-citrate lyase activity. This macrophage PNC synchronizes mitochondrial activity with glycolysis by balancing electron transfer to mitochondria, thereby supporting glycolytic activity and promoting oxidative phosphorylation and mitochondrial H+ and phosphate recycling.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Adenina/metabolismo , Adenosina/metabolismo , Adenosina Desaminase/metabolismo , Cromatografia Líquida/métodos , Células HEK293 , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Espectrometria de Massas/métodos , Enzimas Multifuncionais/genética , Fosforilação , Proteínas/genética , Nucleotídeos de Purina/metabolismo , Purinas/metabolismo
2.
Immunity ; 57(1): 40-51.e5, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38171362

RESUMO

Individuals who clear primary hepatitis C virus (HCV) infections clear subsequent reinfections more than 80% of the time, but the mechanisms are poorly defined. Here, we used HCV variants and plasma from individuals with repeated clearance to characterize longitudinal changes in envelope glycoprotein E2 sequences, function, and neutralizing antibody (NAb) resistance. Clearance of infection was associated with early selection of viruses with NAb resistance substitutions that also reduced E2 binding to CD81, the primary HCV receptor. Later, peri-clearance plasma samples regained neutralizing capacity against these variants. We identified a subset of broadly NAbs (bNAbs) for which these loss-of-fitness substitutions conferred resistance to unmutated bNAb ancestors but increased sensitivity to mature bNAbs. These data demonstrate a mechanism by which neutralizing antibodies contribute to repeated immune-mediated HCV clearance, identifying specific bNAbs that exploit fundamental vulnerabilities in E2. The induction of bNAbs with these specificities should be a goal of HCV vaccine development.


Assuntos
Anticorpos Neutralizantes , Hepatite C , Humanos , Anticorpos Amplamente Neutralizantes , Anticorpos Anti-Hepatite C/química , Hepacivirus , Proteínas do Envelope Viral/genética
4.
Chem Rec ; 24(5): e202400015, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38629935

RESUMO

Substantial amounts of low-value light petroleum fractions and low-value heavy petroleum fractions, such as light naphtha, HVGO, and vacuum residue, are generated during the upgrading and refining of conventional and unconventional petroleum resources. The oil industry emphasizes economic diversification, aiming to produce high-value products from these low petroleum fractions through cost-effective and sustainable methods. Controlled autoxidation (oxidation with air) has the potential to produce industrially important oxygenates, including alcohols, and ketones, from the low-value light petroleum fractions. The produced alcohols can also be converted to olefin through catalytic dehydration. Following controlled autoxidation, the low-value heavy petroleum fractions can be utilized to produce value-added products, including carbon fiber precursors. It would reduce the production cost of a highly demandable product, carbon fiber. This review highlights the prospect of developing an alternative, sustainable, and economic method to produce value-added products from the low-value petroleum fractions following a controlled autoxidation approach.

5.
Pediatr Dermatol ; 41(2): 346-347, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38085129

RESUMO

We report the case of a newborn who was noted at birth to have an occipital scalp nodule presenting with a hair collar sign (HCS). The nodule had enlarged since birth. An MRI revealed a soft tissue mass on the occipital scalp without deep extension or cranial bone involvement. A biopsy of the nodule led to a diagnosis of arteriovenous malformation (AVM). A vascular malformation with HCS has not been reported before in North America. This case highlights the complexity of diagnosing a lesion with a hair collar sign.


Assuntos
Malformações Arteriovenosas , Cabelo , Recém-Nascido , Humanos , Cabelo/patologia , Couro Cabeludo/patologia , Malformações Arteriovenosas/diagnóstico por imagem , Malformações Arteriovenosas/patologia , Crânio , Imageamento por Ressonância Magnética
6.
Planta ; 258(1): 12, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296318

RESUMO

MAIN CONCLUSION: Legumes manage both symbiotic (indirect) and non-symbiotic (direct) nitrogen acquisition pathways. Understanding and optimising the direct pathway for nitrate uptake will support greater legume growth and seed yields. Legumes have multiple pathways to acquire reduced nitrogen to grow and set seed. Apart from the symbiotic N2-fixation pathway involving soil-borne rhizobia bacteria, the acquisition of nitrate and ammonia from the soil can also be an important secondary nitrogen source to meet plant N demand. The balance in N delivery between symbiotic N (indirect) and inorganic N uptake (direct) remains less clear over the growing cycle and with the type of legume under cultivation. In fertile, pH balanced agricultural soils, NO3- is often the predominant form of reduced N available to crop plants and will be a major contributor to whole plant N supply if provided at sufficient levels. The transport processes for NO3- uptake into legume root cells and its transport between root and shoot tissues involves both high and low-affinity transport systems called HATS and LATS, respectively. These proteins are regulated by external NO3- availability and by the N status of the cell. Other proteins also play a role in NO3- transport, including the voltage dependent chloride/nitrate channel family (CLC) and the S-type anion channels of the SLAC/SLAH family. CLC's are linked to NO3- transport across the tonoplast of vacuoles and the SLAC/SLAH's with NO3- efflux across the plasma membrane and out of the cell. An important step in managing the N requirements of a plant are the mechanisms involved in root N uptake and the subsequent cellular distribution within the plant. In this review, we will present the current knowledge of these proteins and what is understood on how they function in key model legumes (Lotus japonicus, Medicago truncatula and Glycine sp.). The review will examine their regulation and role in N signalling, discuss how post-translational modification affects NO3- transport in roots and aerial tissues and its translocation to vegetative tissues and storage/remobilization in reproductive tissues. Lastly, we will present how NO3-influences the autoregulation of nodulation and nitrogen fixation and its role in mitigating salt and other abiotic stresses.


Assuntos
Lotus , Nitratos , Nitratos/metabolismo , Simbiose/fisiologia , Nitrogênio/metabolismo , Lotus/fisiologia , Verduras/metabolismo , Solo , Raízes de Plantas/metabolismo , Proteínas de Plantas/metabolismo
7.
Curr Atheroscler Rep ; 25(9): 571-578, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37606811

RESUMO

PURPOSE OF REVIEW: Cardiovascular diseases (CVDs) are a leading cause of morbidity and mortality globally with an accelerated increase in CVD­related death in Africa and other low­middle­income countries. This review is aimed at highlighting the burden of coronary artery disease CAD, its peculiarities as well as challenges of management in sub-Saharan Africa. RECENT FINDINGS: Recent data revealed a shift from high incidence of CVDs associated with poverty and malnutrition (such as rheumatic heart disease) initially, which are now falling, to rising incidence of other non-communicable CVDs (such as hypertension, coronary artery disease (CAD), and heart failure). Africa disproportionately bears the brunt of CVD burden and has one of the highest risks of dying from non-communicable diseases (NCDs) worldwide, which is projected to supersede communicable diseases in the future. Previous studies have shown that CAD was rare among Africans. Those studies conducted in Africa in the 1940s-1960s reported that Black Africans were almost immune to developing CAD and were even thought to have specific genetic make-up protecting them from CAD. However, the continent is now experiencing a steady rise in the prevalence of CAD associated with severe disease burden, compared to other regions of the world. The changes seen have been attributed to the current epidemiological transition with increase in CVD risk factors that are poorly controlled, lack of awareness as well as the poor health facilities to tackle the menace of the disease. The Global Burden of Disease (GBD) estimates have also shown that over the past three decades the highest contribution to CVD burden in Africa is attributed to atherosclerotic diseases, with 71.4, 37.7, and 154% increases in the burden of ischemic heart disease, stroke, and peripheral artery disease respectively. There is a steady increase of CAD prevalence in Africa as a result of increase in CV risk factors. Hypertension, obesity, diabetes, dyslipidemia, and cigarette smoking are the rapidly rising risk factors for CAD on the continent. Africa also faces challenges in diagnosis and management of CAD. There is need for increased public and health personnel awareness on prevention and control of commonly identifiable risk factors, provision of prehospital emergency services, and provision of modern therapeutic facilities for treatment of CAD including reperfusion therapy. These are priority areas where efforts could be intensified in the future with potential to improve the current rate of progress of the disease on the continent.


Assuntos
Doenças Cardiovasculares , Doença da Artéria Coronariana , Hipertensão , Humanos , Doença da Artéria Coronariana/epidemiologia , Pandemias , Doenças Cardiovasculares/epidemiologia , África Subsaariana/epidemiologia
8.
J Public Health (Oxf) ; 45(2): 338-346, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-36418235

RESUMO

BACKGROUND: Tuberculosis (TB) like many other infectious diseases has a strong relationship with climatic parameters. METHODS: The present study has been carried out on the newly diagnosed sputum smear-positive pulmonary TB cases reported to National TB Control Program across Pakistan from 2007 to 2020. In this study, spatial and temporal distribution of the disease was observed through detailed district wise mapping and clustered regions were also identified. Potential risk factors associated with this disease depending upon population and climatic variables, i.e. temperature and precipitation were also identified. RESULTS: Nationwide, the incidence rate of TB was observed to be rising from 7.03% to 11.91% in the years 2007-2018, which then started to decline. However, a declining trend was observed after 2018-2020. The most populous provinces, Punjab and Sindh, have reported maximum number of cases and showed a temporal association as the climatic temperature of these two provinces is higher with comparison to other provinces. Machine learning algorithms Maxent, Support Vector Machine (SVM), Environmental Distance (ED) and Climate Space Model (CSM) predict high risk of the disease with14.02%, 24.75%, 34.81% and 43.89% area, respectively. CONCLUSION: SVM has a higher significant probability of prediction in the diseased area with a 1.86 partial receiver-operating characteristics (ROC) value as compared with other models.


Assuntos
Tuberculose Pulmonar , Tuberculose , Humanos , Paquistão/epidemiologia , Tuberculose/epidemiologia , Tuberculose/diagnóstico , Tuberculose Pulmonar/epidemiologia , Fatores de Risco , Simulação por Computador
9.
Luminescence ; 38(10): 1803-1813, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37519273

RESUMO

A responsive spectrofluorometric method was developed for the determination of sitagliptin phosphate using l-tyrosine as a fluorescence probe. The fluorescence intensity of l-tyrosine was quenched with sitagliptin phosphate. The fluorescence intensity was recorded at 307 nm using a 272 nm excitation wavelength. The calibration plot between fluorescence intensity and the concentration of drug was linear in the range of 0.1 to 2.0 mM with a good correlation value of 0.997. The limit of detection and quantification were established to be 3.7 × 10-4 and 1.23 × 10-3  mM, respectively. Commonly used excipients did not interfere with sitagliptin phosphate measurement. The proposed method was used to measure the sitagliptin phosphate in its standard type, dosage form, and biological samples. The percent recovery ranged from 97.41-103.36%. The static quenching was shown to be responsible for quenching as indicated by the Stern-Volmer plot. The method was validated using ICH guidelines and profitably applied for the content uniformity test, resulting in a high percent recovery and small relative standard deviation. The proposed approach is effortless, susceptible, selective, economic, and provides a high precision and accuracy, and can be used to determine sitagliptin phosphate in the pharmaceutical industry.


Assuntos
Fosfato de Sitagliptina , Tirosina , Fluorescência , Preparações Farmacêuticas , Espectrometria de Fluorescência/métodos
10.
Arch Pharm (Weinheim) ; 356(1): e2200356, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36220614

RESUMO

A series of xanthene-based thiazoles was synthesized and characterized by different scpectroscopic methods, i.e. Proton nuclear magnetic resonance (1 H NMR), carbon nuclear magnetic resonance (13 C NMR), infrared spectroscopy, carbon hydrogen nitrogen analysis, and X-ray crystallography. The inhibition potencies of 18 newly synthesized thiazole derivatives were investigated on the activities of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-amylase (α-Amy), and α-glycosidase (α-Gly) enzymes in accordance with their antidiabetic and anticholinesterase ability. The synthesized compounds have the highest inhibition potential against the enzymes at low nanomolar concentrations. Among the 18 newly synthesized molecules, 3b and 3p were superior to the known commercial inhibitors of the enzymes and have a much more effective inhibitory potential, with IC50 : 2.37 and 1.07 nM for AChE, 0.98 and 0.59 nM for BChE, 56.47 and 61.34 nM for α-Gly, and 152.48 and 124.84 nM for α-Amy, respectively. Finally, the optimized 18 compounds were subjected to molecular docking to describe the interaction between thiazole derivatives and AChE, BChE, α-Amy, and α-Gly enzymes in which important interactions were monitored with amino acid residues of each target enzyme.


Assuntos
Acetilcolinesterase , Butirilcolinesterase , Butirilcolinesterase/metabolismo , Acetilcolinesterase/metabolismo , Hipoglicemiantes/farmacologia , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Tiazóis , Inibidores da Colinesterase/química , Glicosídeo Hidrolases/metabolismo
11.
Med J Malaysia ; 78(2): 131-138, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36988520

RESUMO

INTRODUCTION: COVID-19 patients frequently demonstrate radiological organising pneumonia (OP) pattern. The longterm outcome and treatment options for this group of patients remain uncertain. We aim to describe the clinical and radiological outcomes of patients with COVID-19-related OP and identify possible clinical factors associated with inferior radiological outcome. MATERIALS AND METHODS: Post-COVID-19 clinic attendees, consisting of post-COVID-19 patients discharged from major hospitals in the state of Selangor during the third pandemic wave of COVID-19 in Malaysia, were enrolled in this retrospective study for 6 months. Physician-scored Modified Medical Research Council (mMRC), patient self-reported quality of life (EQ-VAS) score and follow-up CT scan were evaluated. RESULTS: Our cohort comprised 131 patients, with a median age of 52 (IQR 39-60) years and median BMI of 29.40 (IQR 25.59-34.72). Majority (72.5%) had co-morbidities, and 97.7% had severe disease requiring supplementary oxygen support during the acute COVID-19 episode. 56.5% required intensive care; among which one-third were invasively ventilated. Median equivalent dose of methylprednisolone prescribed was 2.60 (IQR 1.29-5.18) mg/kg during admission, while the median prednisolone dose upon discharge was 0.64 (IQR 0.51-0.78) mg/kg. It was tapered over a median of 8.0 (IQR 5.8-9.0) weeks. Upon follow-up at 11 (IQR 8-15) weeks, one-third of patients remained symptomatic, with cough, fatigue and dyspnoea being the most reported symptoms. mMRC and EQ-VAS scores improved significantly (p<0.001) during follow-up. Repeat CT scans were done in 59.5% of patients, with 94.8% of them demonstrating improvement. In fact, 51.7% had complete radiological resolution. Intensive care admission and mechanical ventilation are among the factors which were associated with poorer radiological outcomes, p<0.05. CONCLUSION: Approximately one-third of patients with SARSCoV- 2-related OP remained symptomatic at 3 months of follow-up. Majority demonstrated favourable radiological outcomes at 5-month reassessment, except those who required intensive care unit admission and mechanical ventilation.


Assuntos
COVID-19 , Pneumonia em Organização , Humanos , Adulto , Pessoa de Meia-Idade , SARS-CoV-2 , Estudos Retrospectivos , Qualidade de Vida
12.
Neurobiol Dis ; 174: 105879, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36183946

RESUMO

GABAergic interneurons play a role in regulating adult neurogenesis within the dentate gyrus (DG) of the hippocampus. Neurogenesis occurs within a stem cell niche in the subgranular zone (SGZ) of the DG. In this niche, populations of neural progenitors give rise to granule cells that migrate radially into the granule cell layer (GCL) of the DG. Altered neurogenesis in temporal lobe epilepsy (TLE) is linked to a transient increase in the proliferation of new neurons and the abnormal inversion of Type 1 progenitors, resulting in ectopic migration of Type 3 progenitors into the hilus of the DG. These ectopic cells mature into granule cells in the hilus that become hyperexcitable and contribute to the development of spontaneous recurrent seizures. To test whether grafts of GABAergic cells in the DG restore synaptic inhibition, prior work focused on transplanting GABAergic progenitors into the hilus of the DG. This cell-based therapeutic approach was shown to alter the disease phenotype by ameliorating spontaneous seizures in mice with pilocarpine-induced TLE. Prior optogenetic and immunohistochemical studies demonstrated that the transplanted GABAergic interneurons increased levels of synaptic inhibition by establishing inhibitory synaptic contacts with adult-born granule cells, consistent with the observed suppression of seizures. Whether GABAergic progenitor transplantation into the DG ameliorates underlying abnormalities in adult neurogenesis caused by TLE is not known. As a first step to address this question, we compared the effects of GABAergic progenitor transplantation on Type 1, Type 2, and Type 3 progenitors in the stem cell niche using cell type-specific molecular markers in naïve, non-epileptic mice. The progenitor transplantation increased GABAergic interneurons in the DG and led to a significant reduction in Type 2 progenitors and a concomitant increase in Type 3 progenitors. Next, we compared the effects of GABAergic interneuron transplantation in epileptic mice. Transplantation of GABAergic progenitors resulted in reductions in inverted Type 1, Type 2, and hilar ectopic Type 3 cells, concomitant with an increase in the radial migration of Type 3 progenitors into the GCL. Thus, in mice with Pilocarpine induced TLE, hilar transplants of GABA interneurons may reverse abnormal patterns of adult neurogenesis, an outcome that may ameliorate seizures.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Camundongos , Animais , Epilepsia do Lobo Temporal/induzido quimicamente , Pilocarpina , Neurogênese/fisiologia , Hipocampo/fisiologia , Convulsões , Giro Denteado/fisiologia
13.
Br J Cancer ; 127(1): 126-136, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35306539

RESUMO

BACKGROUND: Serious and potentially life-threatening toxicities can occur following 5-fluorouracil/capecitabine exposure. Patients carrying Dihydropyrimidine Dehydrogenase (DPYD) variant alleles associated with decreased enzymatic function are at a greater risk of early/severe 5-fluorouracil/capecitabine toxicity. The objective of this systematic review/meta-analysis was to evaluate treatment outcomes between Pharmacogenetics Guided Dosing (PGD) versus non-PGD and within PGD (DPYD variant allele carriers versus wild type). METHODS: A systematic review/meta-analysis of original publications indexed in Ovid Medline, Ovid Embase, and the Cochrane CENTRAL (Wiley) library from inception to 7-Dec-2020. Eligible studies evaluated at least one pre-defined treatment outcome measures (toxicity/hospitalisations/survival/overall response/quality of life). RESULTS: Of 1090 identified publications, 17 met predefined eligibility criteria. The meta-analysis observed reduced incidence of grade 3/4 overall toxicity (Risk Ratio [RR] 0.32 [95% Cl 0.27-0.39], p < 0.00001) and grade 3/4 diarrhoea (RR 0.38 [95% Cl 0.24-0.61], p < 0.0001) among PGD versus non-PGD cohorts. Within PGD cohorts, there was no statistical differences for overall response rates (complete/partial) (RR 1.31 [95% Cl 0.93-1.85], p = 0.12). Similar results were found with stable disease (RR 1.27 [95% Cl 0.66-2.44], p = 0.47). CONCLUSION: PGD improves patient outcomes in terms of grade 3/4 toxicity, in particular overall toxicity and diarrhoea, without impacting on treatment response. REGISTRATION NUMBER: The study is registered with PROSPERO, registration number CRD42020223768.


Assuntos
Farmacogenética , Qualidade de Vida , Capecitabina/efeitos adversos , Diarreia/induzido quimicamente , Di-Hidrouracila Desidrogenase (NADP)/genética , Fluoruracila/efeitos adversos , Humanos , Padrão de Cuidado , Resultado do Tratamento
14.
Clin Gastroenterol Hepatol ; 20(3): 631-640.e1, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33309984

RESUMO

BACKGROUND & AIMS: The Charlson Comorbidity Index (CACI) has been suggested as a tool to determine comorbidity burden and guide management for patients with mucinous pancreatic cysts (Intrapapillary Mucinous Neoplasms and Mucinous Cystic Neoplasms), but has not been studied well among "low-risk" mucinous pancreatic cysts i.e. without worrisome features (WF) and high-risk stigmata (HRS). This study sought to determine the comorbidity burden among surveillance population of low-risk pancreatic cysts and provide their follow-up mortality outcomes. METHODS: A single center study retrospectively reviewed a prospective pancreatic cyst database and included individuals with low-risk cysts undergoing serial imaging during 2016. Electronic medical records were reviewed to determine their baseline age-adjusted CACI (age-CACI). After 4 years, their progression to WF, disease specific (pancreatic malignancy-related, DSM), extra-pancreatic (EPM), and overall mortalities (OM) were determined using Kaplan-Meir Survival Analysis. RESULTS: 502 individuals underwent prospective surveillance. The study included 440 individuals with low-risk suspected or presumed mucinous cysts and excluded 50 and 12 individuals with WF and HRS respectively. Over a median follow-up of 56 months, 12 WF progressions, 2 DSMs, 42 EPMs, and 44 OMs were observed. Baseline age-CACI had good predictive capacity for 4-year EPM (Area-Under Curve: 0.87; p< .0001). The median age-CACI of 4 enabled cohort stratification into Low (age-CACI <4) and High CACI (age-CACI ≥4) groups. A significantly higher OM (p< .001) was observed among the High CACI group as compared to the Low CACI group. CONCLUSION: Through real-time application of CACI to patient outcomes, our analysis supports incorporation of this comorbidity assessment tool in making shared surveillance decisions among low-risk pancreatic cyst population.


Assuntos
Cisto Pancreático , Neoplasias Pancreáticas , Comorbidade , Humanos , Cisto Pancreático/epidemiologia , Neoplasias Pancreáticas/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos
15.
Endoscopy ; 54(5): 498-502, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34710910

RESUMO

BACKGROUND: Cricopharyngeal bars (CPBs) are a unique etiology of oropharyngeal dysphagia. Symptomatic patients are managed with endoscopic dilation or surgical myotomy. Cricopharyngeal peroral endoscopic myotomy (CP-POEM) is an emerging technique for the management of dysphagia due to CPBs. This study evaluated technical success, clinical success, adverse events, and long-term recurrence following CP-POEM. METHODS: Consecutive patients who underwent POEM for management of CPBs between May 2015 and December 2020 at four tertiary care centers were included. Primary outcome was clinical success (defined as improvement of dysphagia score to ≤ 1). Secondary outcomes were technical success, rate and severity of adverse events, procedure duration, and symptom recurrence. RESULTS: 27 patients (mean age 69 years; 10 female) underwent CP-POEM during the study period. The most common presenting symptoms at the time of index procedure were dysphagia (26; 96.3 %) and regurgitation (20; 74.1 %). Clinical and technical success were achieved in all patients. Mild/moderate adverse events occurred in two patients (7.4 %). CP-POEM significantly reduced the median dysphagia score. CONCLUSIONS: CP-POEM was a safe and effective treatment for symptomatic CPBs. Although symptom recurrence was low, long-term outcome data are needed. CP-POEM should be considered as a management option for symptomatic CPBs at centers with POEM expertise.


Assuntos
Transtornos de Deglutição , Procedimentos Cirúrgicos do Sistema Digestório , Acalasia Esofágica , Doenças do Esôfago , Miotomia , Cirurgia Endoscópica por Orifício Natural , Idoso , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/cirurgia , Acalasia Esofágica/cirurgia , Doenças do Esôfago/etiologia , Esfíncter Esofágico Inferior/cirurgia , Feminino , Humanos , Masculino , Miotomia/efeitos adversos , Miotomia/métodos , Cirurgia Endoscópica por Orifício Natural/efeitos adversos , Cirurgia Endoscópica por Orifício Natural/métodos , Estudos Retrospectivos , Resultado do Tratamento
16.
Endoscopy ; 54(4): 345-351, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34198355

RESUMO

BACKGROUND: Treatment of Zenker's diverticulum has evolved from open surgery to endoscopic techniques, including flexible and rigid endoscopic septotomy, and more recently, peroral endoscopic myotomy (Z-POEM). This study compared the effectiveness of flexible and rigid endoscopic septotomy with that of Z-POEM. METHODS: Consecutive patients who underwent endoscopic septotomy (flexible/rigid) or Z-POEM for Zenker's diverticulum between 1/2016 and 9/2019 were included. Primary outcomes were clinical success (decrease in Dakkak and Bennett dysphagia score to ≤ 1), clinical failure, and clinical recurrence. Secondary outcomes included technical success and rate/severity of adverse events. RESULTS: 245 patients (110 females, mean age 72.63 years, standard deviation [SD] 12.37 years) from 12 centers were included. Z-POEM was the most common management modality (n = 119), followed by flexible (n = 86) and rigid (n = 40) endoscopic septotomy. Clinical success was 92.7 % for Z-POEM, 89.2 % for rigid septotomy, and 86.7 % for flexible septotomy (P = 0.26). Symptoms recurred in 24 patients (15 Z-POEM during a mean follow-up of 282.04 [SD 300.48] days, 6 flexible, 3 rigid [P = 0.47]). Adverse events occurred in 30.0 % rigid septotomy patients, 16.8 % Z-POEM patients, and 2.3 % flexible septotomy patients (P < 0.05). CONCLUSIONS: There was no difference in outcomes between the three treatment approaches for symptomatic Zenker's diverticulum. Rigid endoscopic septotomy was associated with the highest rate of complications, while flexible endoscopic septotomy appeared to be the safest. Recurrence following Z-POEM was similar to flexible and rigid endoscopic septotomy. Prospective studies with long-term follow-up are required.


Assuntos
Miotomia , Divertículo de Zenker , Idoso , Esofagoscopia/efeitos adversos , Feminino , Humanos , Masculino , Miotomia/efeitos adversos , Miotomia/métodos , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Divertículo de Zenker/cirurgia
17.
Langmuir ; 38(28): 8485-8494, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35797459

RESUMO

Selenium is an important earth-abundant and nontoxic semiconductor with numerous applications across semiconductor industries. Selenium has drawn attention from scientific communities for photovoltaics and imaging devices. Its usage as a photosensitive material largely involves the synthesis of the amorphous phase (a-Se) via various experimental techniques. However, the ground state crystalline phase of this material, the trigonal selenium (t-Se), a layered van der Waals solid, has not been extensively studied for its optimum electronic and optical properties. In this work, we present systematic studies based on density functional theory (DFT) for ultrathin (101̅0) surface slabs of t-Se. We report the surface energy as well as work function and electronic and optical properties as a function of number of layers for (101̅0) surface slabs to access its suitability for applications as a photosensitive material and compare these calculations to historical data.

18.
Chem Rec ; 22(7): e202200022, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35502847

RESUMO

Liquid phase oxidation (LPO) of hydrocarbon is an industrially important process to produce petrochemicals and pharmaceuticals. It follows a free radical path having initiation, propagation and termination. The initiation step is slow while the propagation and termination steps are fast. The main challenge of such process is to control product selectivity at an appreciable conversion level. With the advancement of microfluidic reactor technology, it is possible to control the free radical steps. The present contribution critically reviewed the reaction engineering aspects of LPO of hydrocarbon, the influence of microfluidic reactor design and operation on reaction mechanism, conversion and product selectivity. It also outlines the challenges associated with microfluidic reactor operation, and prospects to apply the understanding from microfluidic reactors in few sectors. The understanding from the free radical oxidation process can also be applied to any other free radical processes.


Assuntos
Hidrocarbonetos , Microfluídica , Radicais Livres , Oxirredução
19.
Proc Natl Acad Sci U S A ; 116(52): 26382-26388, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31818944

RESUMO

The glaciers near Puncak Jaya in Papua, Indonesia, the highest peak between the Himalayas and the Andes, are the last remaining tropical glaciers in the West Pacific Warm Pool (WPWP). Here, we report the recent, rapid retreat of the glaciers near Puncak Jaya by quantifying the loss of ice coverage and reduction of ice thickness over the last 8 y. Photographs and measurements of a 30-m accumulation stake anchored to bedrock on the summit of one of these glaciers document a rapid pace in the loss of ice cover and a ∼5.4-fold increase in the thinning rate, which was augmented by the strong 2015-2016 El Niño. At the current rate of ice loss, these glaciers will likely disappear within the next decade. To further understand the mechanisms driving the observed retreat of these glaciers, 2 ∼32-m-long ice cores to bedrock recovered in mid-2010 are used to reconstruct the tropical Pacific climate variability over approximately the past half-century on a quasi-interannual timescale. The ice core oxygen isotopic ratios show a significant positive linear trend since 1964 CE (0.018 ± 0.008‰ per year; P < 0.03) and also suggest that the glaciers' retreat is augmented by El Niño-Southern Oscillation processes, such as convection and warming of the atmosphere and sea surface. These Papua glaciers provide the only tropical records of ice core-derived climate variability for the WPWP.

20.
J Basic Microbiol ; 62(2): 95-108, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34878177

RESUMO

Hot springs ecosystem is the most ancient continuously inhabited ecosystem on earth which harbors diverse thermophilic bacteria and archaea distributed worldwide. Life in extreme environments is very challenging so there is a great potential biological dark matter and their adaptation to harsh environments eventually producing thermostable enzymes which are very vital for the welfare of mankind. There is an enormous need for a new generation of stable enzymes that can endure harsh conditions in industrial processes and can either substitute or complement conventional chemical processes. Here, we review at the variety and distribution of thermophilic microbes, as well as the different thermostable enzymes that help them survive at high temperatures, such as proteases, amylases, lipases, cellulases, pullulanase, xylanases, and DNA polymerases, as well as their special properties, such as high-temperature stability. We have documented the novel isolated thermophilic and hyperthermophilic microorganisms, as well as the discovery of their enzymes, demonstrating their immense potential in the scientific community and in industry.


Assuntos
Celulases , Ecossistema , Archaea/genética , Biotecnologia , Temperatura Alta
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