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1.
Cell ; 184(18): 4713-4733.e22, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34352228

RESUMO

SARS-CoV-2 infection can cause severe respiratory COVID-19. However, many individuals present with isolated upper respiratory symptoms, suggesting potential to constrain viral pathology to the nasopharynx. Which cells SARS-CoV-2 primarily targets and how infection influences the respiratory epithelium remains incompletely understood. We performed scRNA-seq on nasopharyngeal swabs from 58 healthy and COVID-19 participants. During COVID-19, we observe expansion of secretory, loss of ciliated, and epithelial cell repopulation via deuterosomal cell expansion. In mild and moderate COVID-19, epithelial cells express anti-viral/interferon-responsive genes, while cells in severe COVID-19 have muted anti-viral responses despite equivalent viral loads. SARS-CoV-2 RNA+ host-target cells are highly heterogenous, including developing ciliated, interferon-responsive ciliated, AZGP1high goblet, and KRT13+ "hillock"-like cells, and we identify genes associated with susceptibility, resistance, or infection response. Our study defines protective and detrimental responses to SARS-CoV-2, the direct viral targets of infection, and suggests that failed nasal epithelial anti-viral immunity may underlie and precede severe COVID-19.


Assuntos
COVID-19/imunologia , COVID-19/virologia , Imunidade , SARS-CoV-2/fisiologia , Índice de Gravidade de Doença , Adulto , Idoso , Efeito Espectador , COVID-19/genética , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/patologia , Nasofaringe/virologia , RNA Viral/análise , RNA Viral/genética , Mucosa Respiratória/patologia , Mucosa Respiratória/virologia , Transcrição Gênica , Carga Viral
2.
Cell ; 181(5): 1016-1035.e19, 2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32413319

RESUMO

There is pressing urgency to understand the pathogenesis of the severe acute respiratory syndrome coronavirus clade 2 (SARS-CoV-2), which causes the disease COVID-19. SARS-CoV-2 spike (S) protein binds angiotensin-converting enzyme 2 (ACE2), and in concert with host proteases, principally transmembrane serine protease 2 (TMPRSS2), promotes cellular entry. The cell subsets targeted by SARS-CoV-2 in host tissues and the factors that regulate ACE2 expression remain unknown. Here, we leverage human, non-human primate, and mouse single-cell RNA-sequencing (scRNA-seq) datasets across health and disease to uncover putative targets of SARS-CoV-2 among tissue-resident cell subsets. We identify ACE2 and TMPRSS2 co-expressing cells within lung type II pneumocytes, ileal absorptive enterocytes, and nasal goblet secretory cells. Strikingly, we discovered that ACE2 is a human interferon-stimulated gene (ISG) in vitro using airway epithelial cells and extend our findings to in vivo viral infections. Our data suggest that SARS-CoV-2 could exploit species-specific interferon-driven upregulation of ACE2, a tissue-protective mediator during lung injury, to enhance infection.


Assuntos
Células Epiteliais Alveolares/metabolismo , Enterócitos/metabolismo , Células Caliciformes/metabolismo , Interferon Tipo I/metabolismo , Mucosa Nasal/citologia , Peptidil Dipeptidase A/genética , Adolescente , Células Epiteliais Alveolares/imunologia , Enzima de Conversão de Angiotensina 2 , Animais , Betacoronavirus/fisiologia , COVID-19 , Linhagem Celular , Células Cultivadas , Criança , Infecções por Coronavirus/virologia , Enterócitos/imunologia , Células Caliciformes/imunologia , Infecções por HIV/imunologia , Humanos , Influenza Humana/imunologia , Interferon Tipo I/imunologia , Pulmão/citologia , Pulmão/patologia , Macaca mulatta , Camundongos , Mycobacterium tuberculosis , Mucosa Nasal/imunologia , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/virologia , Receptores Virais/genética , SARS-CoV-2 , Serina Endopeptidases/metabolismo , Análise de Célula Única , Tuberculose/imunologia , Regulação para Cima
3.
J Theor Biol ; 577: 111672, 2024 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-37984585

RESUMO

Several studies have developed dynamical models to understand the underlying mechanisms of insulin signaling, a signaling cascade that leads to the translocation of glucose, the human body's main source of energy. Fortunately, reaction network analysis allows us to extract properties of dynamical systems without depending on their model parameter values. This study focuses on the comparison of insulin signaling in healthy state (INSMS or INSulin Metabolic Signaling) and in type 2 diabetes (INRES or INsulin RESistance) using reaction network analysis. The analysis uses network decomposition to identify the different subsystems involved in insulin signaling (e.g., insulin receptor binding and recycling, GLUT4 translocation, and ERK signaling pathway, among others). Furthermore, results show that INSMS and INRES are similar with respect to some network, structo-kinetic, and kinetic properties. Their differences, however, provide insights into what happens when insulin resistance occurs. First, the variation in the number of species involved in INSMS and INRES suggests that when irregularities occur in the insulin signaling pathway, other complexes (and, hence, other processes) get involved, characterizing insulin resistance. Second, the loss of concordance exhibited by INRES suggests less restrictive interplay between the species involved in insulin signaling, leading to unusual activities in the signaling cascade. Lastly, GLUT4 losing its absolute concentration robustness in INRES may signify that the transporter has lost its reliability in shuttling glucose to the cell, inhibiting efficient cellular energy production. This study also suggests possible applications of the equilibria parametrization and network decomposition, resulting from the analysis, to potentially establish absolute concentration robustness in a species.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Insulina/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais , Glucose/metabolismo
4.
PLoS Comput Biol ; 19(4): e1011039, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37053305

RESUMO

The long-term behaviors of biochemical systems are often described by their steady states. Deriving these states directly for complex networks arising from real-world applications, however, is often challenging. Recent work has consequently focused on network-based approaches. Specifically, biochemical reaction networks are transformed into weakly reversible and deficiency zero generalized networks, which allows the derivation of their analytic steady states. Identifying this transformation, however, can be challenging for large and complex networks. In this paper, we address this difficulty by breaking the complex network into smaller independent subnetworks and then transforming the subnetworks to derive the analytic steady states of each subnetwork. We show that stitching these solutions together leads to the analytic steady states of the original network. To facilitate this process, we develop a user-friendly and publicly available package, COMPILES (COMPutIng anaLytic stEady States). With COMPILES, we can easily test the presence of bistability of a CRISPRi toggle switch model, which was previously investigated via tremendous number of numerical simulations and within a limited range of parameters. Furthermore, COMPILES can be used to identify absolute concentration robustness (ACR), the property of a system that maintains the concentration of particular species at a steady state regardless of any initial concentrations. Specifically, our approach completely identifies all the species with and without ACR in a complex insulin model. Our method provides an effective approach to analyzing and understanding complex biochemical systems.


Assuntos
Modelos Biológicos , Modelos Químicos
5.
Arch Virol ; 169(7): 138, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847856

RESUMO

Human norovirus (HuNoV) is responsible for most cases of gastroenteritis worldwide, but information about the prevalence and diversity of HuNoV infections in lower-income settings is lacking. In order to provide more information about the burden and distribution of norovirus in Nigeria, we systematically reviewed original published research articles on the prevalence of HuNoV in Nigeria by accessing databases, including PubMed, Web of Science, ScienceDirect, Google Scholar, and African Journals Online (AJOL). The protocol for the review was registered on PROSPERO (registration number CRD42022308857). Thirteen relevant articles were included in the review, and 10 of them were used for meta-analysis. The pooled prevalence of HuNoV-associated gastroenteritis among children below 5 years of age in Nigeria, determined using the random-effects model, was 10.9% (95% CI, 6.7-16.7%). Among children below the age of 5 presenting with HuNoV infections, the highest prevalence was in children ≤2 years old (n = 127, 83%). The prevalence of HuNoV infections was seen to decrease with increasing age. In addition, HuNoV was detected in asymptomatic food handlers, bats, and seafoods. A total of 85 sequences of HuNoV isolates from Nigeria have been determined, and based on those sequences, the most prevalent norovirus genogroup was GII (84%). Genotypes GII.4 and GI.3 were the most frequently identified genotypes, with GII.4 constituting 46% of all of the HuNoVs identified in Nigeria. These results suggest a risk associated with cocirculation of emerging variants with known genotypes because of their recombination potential. Larger molecular epidemiological studies are still needed to fully understand the extent and pattern of circulation of HuNoVs in Nigeria.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Pré-Escolar , Humanos , Lactente , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Genótipo , Nigéria/epidemiologia , Norovirus/genética , Norovirus/classificação , Norovirus/isolamento & purificação , Filogenia , Prevalência , Recém-Nascido
6.
Rocz Panstw Zakl Hig ; 75(1): 21-33, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38578155

RESUMO

Objective: The aim of the study was to determine Vitamin C content in some fruits and vegetables (FAV) including apple, banana, orange, pineapple, watermelon, carrot and cucumber, sold in the local markets in Awka, Anambra State, Nigeria as well as Vitamin C content in two-component and three-component homogenates FAV. The work was also designed to investigate the dietary exposure and health effects of excess vitamin C intake in adults and children. Material and methods: Vitamin C as total ascorbic acid (AA) after reduction of dehydroascorbic acid was analyzed using both titrimetric and spectrophotometric methods. The titrimetric method involved iodometric back-titration while the spectrophotometric method was done at an absorbance of 530 nm. The dietary exposure was evaluated as the total FAV intake multiplied by chemical concentration in the FAV whereas the health effect of excess vitamin C intake was conducted using the hazard quotient (HQ). Results: The results revealed that Vitamin C for single fruits ranged from 11.76 - 41.17 mg/L for spectroscopic method and 16.9 - 31.84 mg/L for titrimetric method. Fruit homogenates showed Vitamin C concentrations of 14.70 - 220.58 mg/L and 17.23 - 209.09 mg/L for two-components homogenates: 29.41-132.35 mg/L and 31.05-113.10 mg/L for tri-components homogenates for spectrophotometric and titrimetric methods respectively. The results of dietary exposure and the health effects of excess vitamin C intake showed that children are more susceptible to health issues than adults in illnesses such as nausea, gastrointestinal pains, increased kidney stones and hyperactivity. Conclusion: There is therefore the need for a national recommended dietary allowance for total ascorbic acid (AA) in FAV homogenates from a stakeholder point of view in Nigeria.


Assuntos
Ácido Ascórbico , Frutas , Adulto , Criança , Humanos , Ácido Ascórbico/análise , Frutas/química , Verduras/química , Exposição Dietética , Vitaminas , Dieta
7.
PLoS Pathog ; 17(6): e1009601, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34077488

RESUMO

Onchocerciasis (river blindness), caused by the filarial worm Onchocerca volvulus, is a neglected tropical disease mostly affecting sub-Saharan Africa and is responsible for >1.3 million years lived with disability. Current control relies almost entirely on ivermectin, which suppresses symptoms caused by the first-stage larvae (microfilariae) but does not kill the long-lived adults. Here, we evaluated emodepside, a semi-synthetic cyclooctadepsipeptide registered for deworming applications in companion animals, for activity against adult filariae (i.e., as a macrofilaricide). We demonstrate the equivalence of emodepside activity on SLO-1 potassium channels in Onchocerca volvulus and Onchocerca ochengi, its sister species from cattle. Evaluation of emodepside in cattle as single or 7-day treatments at two doses (0.15 and 0.75 mg/kg) revealed rapid activity against microfilariae, prolonged suppression of female worm fecundity, and macrofilaricidal effects by 18 months post treatment. The drug was well tolerated, causing only transiently increased blood glucose. Female adult worms were mostly paralyzed; however, some retained metabolic activity even in the multiple high-dose group. These data support ongoing clinical development of emodepside to treat river blindness.


Assuntos
Doenças dos Bovinos/tratamento farmacológico , Depsipeptídeos/uso terapêutico , Filaricidas/uso terapêutico , Canais de Potássio Ativados por Cálcio de Condutância Alta/efeitos dos fármacos , Oncocercose/tratamento farmacológico , Oncocercose/veterinária , Animais , Bovinos , Onchocerca/efeitos dos fármacos
8.
PLoS Pathog ; 17(9): e1009804, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34529726

RESUMO

Prior studies have demonstrated that immunologic dysfunction underpins severe illness in COVID-19 patients, but have lacked an in-depth analysis of the immunologic drivers of death in the most critically ill patients. We performed immunophenotyping of viral antigen-specific and unconventional T cell responses, neutralizing antibodies, and serum proteins in critically ill patients with SARS-CoV-2 infection, using influenza infection, SARS-CoV-2-convalescent health care workers, and healthy adults as controls. We identify mucosal-associated invariant T (MAIT) cell activation as an independent and significant predictor of death in COVID-19 (HR = 5.92, 95% CI = 2.49-14.1). MAIT cell activation correlates with several other mortality-associated immunologic measures including broad activation of CD8+ T cells and non-Vδ2 γδT cells, and elevated levels of cytokines and chemokines, including GM-CSF, CXCL10, CCL2, and IL-6. MAIT cell activation is also a predictor of disease severity in influenza (ECMO/death HR = 4.43, 95% CI = 1.08-18.2). Single-cell RNA-sequencing reveals a shift from focused IFNα-driven signals in COVID-19 ICU patients who survive to broad pro-inflammatory responses in fatal COVID-19 -a feature not observed in severe influenza. We conclude that fatal COVID-19 infection is driven by uncoordinated inflammatory responses that drive a hierarchy of T cell activation, elements of which can serve as prognostic indicators and potential targets for immune intervention.


Assuntos
COVID-19/imunologia , COVID-19/mortalidade , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos B/imunologia , Biomarcadores/sangue , Proteínas Sanguíneas/metabolismo , Estudos de Coortes , Estado Terminal/mortalidade , Feminino , Humanos , Imunofenotipagem , Influenza Humana/imunologia , Lectinas Tipo C/imunologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Células T Invariantes Associadas à Mucosa/imunologia , Gravidade do Paciente
9.
Malar J ; 22(1): 73, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864514

RESUMO

BACKGROUND: Plasmodium falciparum resistance to intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) continues to spread throughout sub-Saharan Africa. This study assessed the occurrence of microscopic and sub-microscopic P. falciparum parasitaemia, dihydropteroate synthase mutations associated with resistance to SP and maternal anaemia in the Mount Cameroon area. METHODS: Consenting pregnant women living in semi-rural and semi-urban/urbanized settings were enrolled in this cross-sectional study. Socio-demographic, antenatal and clinical data were documented. Microscopic and sub-microscopic parasitaemia were diagnosed using peripheral blood microscopy and nested polymerase chain reaction (PCR) respectively. The dhps mutations were genotyped by restriction fragment length polymorphism analysis. The presence of A437G, K540E, and A581G was considered a marker for high-level resistance. Haemoglobin levels and anaemia status were determined. RESULTS: Among the women, the prevalence of microscopic and sub-microscopic P. falciparum infection were 7.7% (67/874) and 18.6% (93/500) respectively. Predictors of microscopic infection were younger age (< 21 years) (AOR = 2.89; 95% CI 1.29-6.46) and semi-rural settings (AOR = 2.27; 95% CI 1.31-3.96). Determinants of sub-microscopic infection were the rainy season (AOR, 3.01; 95% CI 1.77-5.13), primigravidity (AOR = 0.45; 95% CI 0.21-0.94) and regular ITN usage (AOR = 0.49; 95% CI 0.27-0.90). Of the145 P. falciparum isolates genotyped, 66.9% (97) carried mutations associated with resistance to SP; 33.8% (49), 0%, 52.4% (76) and 19.3% (28) for A437G, K540E, A581G and A437G + A581G respectively. The A581G mutation was associated with ≥ 3 SP doses evident only among sub-microscopic parasitaemia (P = 0.027) and multigravidae (P = 0.009). Women with microscopic infection were more likely from semi-rural settings (AOR = 7.09; 95% CI 2.59-19.42), to report history of fever (AOR = 2.6; 95% CI 1.07-6.31), to harbour parasites with double resistant mutations (AOR = 6.65; 95% CI 1.85-23.96) and were less likely to have received 2 SP doses (AOR = 0.29; 95% CI 1.07-6.31). Microscopic infection decreased Hb levels more than sub-microscopic infection. CONCLUSION: The occurrence of sub-microscopic P. falciparum parasites resistant to SP and intense malaria transmission poses persistent risk of malaria infection during pregnancy in the area. ITN usage and monitoring spread of resistance are critical.


Assuntos
Di-Hidropteroato Sintase , Malária , Gravidez , Feminino , Humanos , Adulto Jovem , Adulto , Di-Hidropteroato Sintase/genética , Plasmodium falciparum/genética , Camarões/epidemiologia , Estudos Transversais , Mutação
10.
Tetrahedron ; 1342023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36937489

RESUMO

A novel approach for the formation of the highly strained spiro[3.3]heptan-1-one motif was developed through the reaction of 1-sulfonylcyclopropanols and lithiated 1-sulfonylbicyclo[1.1.0]butanes. Following initial nucleophilic addition to the cyclopropanone formed in situ, the resulting 1-bicyclobutylcyclopropanol intermediate is prone to a 'strain-relocating' semipinacol rearrangement in the presence of acid, directly affording the substituted spiro[3.3]heptan-1-one. The process is shown to be fully regio- and stereospecific when starting from a substituted cyclopropanone equivalent, leading to optically active 3-substituted spiro[3.3]heptan-1-ones. The reaction likely proceeds via initial protonation of the bicyclobutyl moiety followed by [1,2]-rearrangement of the resulting cyclopropylcarbinyl cation.

11.
BMC Public Health ; 23(1): 2539, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114971

RESUMO

BACKGROUND: The impact of lower thresholds for elevated blood pressure (BP) on adverse perinatal outcomes has been poorly explored in sub-Saharan African populations. We aimed to explore the association between lower BP cutoffs (according to the 2017 American College of Cardiology/American Heart Association [ACC/AHA] criteria) and adverse perinatal outcomes in Kaya, Burkina Faso. METHODS: This retrospective cohort study included 2,232 women with singleton pregnancies between February and September 2021. BP was categorized according to the ACC/AHA criteria and applied throughout pregnancy. A multivariable Poisson regression model based on Generalized Estimating Equation with robust standard errors was used to evaluate the association between elevated BP, stage 1 hypertension, and adverse perinatal outcomes, controlling for maternal sociodemographic characteristics, parity, and the number of antenatal consultations, and the results were presented as adjusted risk ratios (aRRs) with corresponding 95% confidence intervals (CIs). RESULTS: Of the 2,232 women, 1000 (44.8%) were normotensive, 334 (14.9%) had elevated BP, 759 (34.0%) had stage 1 hypertension, and 139 (6.2%) had stage 2 hypertension. There was no significant association between elevated BP and adverse pregnancy outcomes. Compared to normotensive women, women with elevated BP had a 2.05-fold increased risk of delivery via caesarean section (aRR;2.05, 95%CI; 1.08-3.92), while those with stage 1 hypertension had a 1.41-fold increased risk of having low birth weight babies (aRR; 1.41, 95%CI; 1.06-1.86), and a 1.32-fold increased risk of having any maternal or neonatal adverse outcome (aRR; 1.32, 95%CI; 1.02-1.69). CONCLUSIONS: Our results suggest that the risk of adverse pregnancy outcomes is not increased with elevated BP. Proactive identification of pregnant women with stage 1 hypertension in Burkina Faso can improve hypertension management through enhanced clinical surveillance.


Assuntos
Hipertensão , Hipotensão , Recém-Nascido , Estados Unidos , Feminino , Gravidez , Humanos , Pressão Sanguínea , Estudos Retrospectivos , Cesárea , Burkina Faso/epidemiologia , Hipertensão/epidemiologia , Demografia
12.
Neurosurg Focus ; 55(4): E9, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37778042

RESUMO

Surgical revascularization remains the standard treatment for symptomatic moyamoya disease (MMD). As with any major surgical treatment, revascularization is associated with risks and limitations, denoting the need for noninvasive treatments to improve ischemic symptoms and prevent strokes. Cilostazol is a selective phosphodiesterase III inhibitor with antiplatelet, antithrombotic, and vasodilatory effects commonly used in peripheral vascular disease. Clinical studies assessing the efficacy of cilostazol in the management of stroke and MMD were recently reported, although a comprehensive assessment of the overall evidence is lacking. A systematic scoping review was conducted to assess the early evidence on cilostazol administration in patients with MMD. The inclusion criteria encompassed original human studies primarily focused on cilostazol's safety, efficacy, or utilization in managing MMD patients. A search of the PubMed database was conducted in June 2023, yielding 5 peer-reviewed publications that satisfied the inclusion criteria and were subjected to narrative synthesis. Risk of bias assessment was not applicable due to the scoping nature of this review. East Asian studies demonstrate increasing rates of cilostazol prescriptions for patients with MMD. In a large population-based study, cilostazol was compared to other antiplatelet medications and yielded the largest decrease in mortality among patients with newly diagnosed MMD. Other studies reported significant improvements in cerebral blood flow and cognitive function, which were deemed to be independent of one another. There are limited data on the safety profile of cilostazol in the MMD population, although the evidence derived from various studies performed in the general stroke population can likely provide insights into its potential utility in MMD patients. Cilostazol targets several critical pathways involved in the pathophysiology of MMD. The evidence corroborates the potential benefits of cilostazol for the management of MMD, although these findings should be interpreted with caution due to the small number of studies and lack of randomized trials. Subgroups of patients need to be identified who can safely undergo medical management in lieu of revascularization surgery or to improve surgical outcomes. Additional studies are needed to assess the efficacy and safety of cilostazol therapy, especially in Western populations.


Assuntos
Revascularização Cerebral , Doença de Moyamoya , Acidente Vascular Cerebral , Humanos , Cilostazol/uso terapêutico , Cilostazol/farmacologia , Doença de Moyamoya/tratamento farmacológico , Doença de Moyamoya/cirurgia , Acidente Vascular Cerebral/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico
13.
Environ Monit Assess ; 196(1): 30, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38072841

RESUMO

The occurrence of pathogens in discharged wastewater effluent may constitute potential public health risks. This study assessed the physicochemical and bacteriological characteristics of water samples taken from the Wupa River in Abuja, Nigeria, which receives the final effluent of the Wupa Wastewater Treatment Plant. Sixty sewage/water samples were collected over 12 months from five sampling points. Coliform bacteria and Escherichia coli were simultaneously enumerated using the membrane filtration technique and Chromocult Coliform Agar. HANNA multiparameter metre was used to measure the physicochemical parameters including temperature, pH, electrical conductivity (EC), dissolved oxygen (DO) and total dissolved solids (TDS). Results of the bacteriological analysis showed that impermissible high mean counts of E. coli (≥ 1.2 × 104 CFU/100 ml) and total coliforms (≥ 5.4 × 104 CFU/100 ml) were detected in 95% and 100% of the water samples respectively. These values exceed the acceptable standard limits. The mean values of physicochemical parameters ranged from 6.3 to 8.7, 20.9 to 27.3 °C, 116 to 325.0 µS/cm, 1.3 to 11.4 mg/l and 98.0 to 180.0 mg/l for pH, temperature, EC, DO and TDS respectively, with all conforming to international and national standards. Wupa River seems to have a minor negative environmental impact, per the physicochemical data obtained in this study. However, the high counts of faecal indicator bacteria demonstrated in the effluent samples were higher than those of the river at both upstream and downstream sites, implying that the river microbial load may increase to constitute an unchecked environmental hazard. Adequate disinfection of the Wupa plant effluent before discharge into the Wupa River is imperative.


Assuntos
Monitoramento Ambiental , Purificação da Água , Monitoramento Ambiental/métodos , Escherichia coli , Nigéria , Rios/química , Água
14.
Stroke ; 53(12): 3572-3582, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36134563

RESUMO

BACKGROUND: Moyamoya disease is a chronic, progressive cerebrovascular disease involving occlusion or stenosis of the terminal portion of the internal carotid artery. We conducted an updated systematic review and meta-analysis to investigate clinical and angiographic outcomes comparing direct, combined, and indirect bypass for the treatment of moyamoya disease in adults. METHODS: Two independent authors performed Preferred Reporting Items for Systematic reviews and Meta-Analyses guided literature searches in December 2021 to identify articles reporting clinical/angiographic outcomes in adult moyamoya disease patients undergoing bypass. Primary end points used were ischemic and hemorrhagic strokes, clinical outcomes, and angiographic revascularization. Study quality was evaluated with Newcastle-Ottawa and the Oxford Center for Evidence-Based Medicine scales. RESULTS: Four thousand four hundred fifty seven articles were identified in the initial search; 143 articles were analyzed. There were 3827 direct, 3826 indirect, and 3801 combined bypasses. Average length of follow-up was 3.59±2.93 years. Pooled analysis significantly favored direct (odds ratio [OR], 0.62 [0.48-0.79]; P<0.0001; OR, 0.44 [0.32-0.59]; P<0.0001; OR, 0.56 [0.42-0.74]; P<0.0001; OR, 3.1 [2.5-3.8]; P=0.0001) and combined (OR, 0.53 [0.41-0.69]; P<0.0001; OR, 0.28 [0.2-0.41]; P<0.0001; OR, 0.41 [0.3-0.56]; P<0.0001; OR, 3.1 [2.8-4.3]; P=0.0001) over indirect bypass for early stroke, late stroke, late intracerebral hemorrhage, and favorable outcomes, respectively. Indirect bypass was favored over combined (OR, 3.1 [1.7-5.6]; P<0.0001) and direct (OR, 4.12 [2.34-7.25]; P<0.0001) for early intracerebral hemorrhage. The meta-analysis significantly favored direct (OR, 0.37 [0.23-0.60]; P<0.001; OR, 0.49 [0.31-0.77]; P=0.002) and combined (OR, 0.23 [0.12-0.43]; P<0.00001; OR, 0.30 [0.18-0.49]; P<0.00001) bypass over indirect bypass for late stroke and late hemorrhage, respectively. Combined bypass was favored over indirect bypass for favorable outcomes (OR, 2.06 [1.18-3.58]; P=0.01). CONCLUSIONS: Based on combined meta-analysis (43 articles) and pooled analysis (143 articles), the existing literature indicates that combined and direct bypasses have significant benefits for patients suffering from late stroke and hemorrhage versus indirect bypass. Combined bypass was favored over indirect bypass for favorable outcomes. This is a strong recommendation based on low-quality evidence when utilizing the Grades of Recommendation, Assessment, Development, and Evaluation system. These findings have important implications for bypass strategy selection.


Assuntos
Revascularização Cerebral , Doença de Moyamoya , Acidente Vascular Cerebral , Adulto , Humanos , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Revascularização Cerebral/efeitos adversos , Acidente Vascular Cerebral/etiologia , Hemorragia Cerebral/etiologia , Resultado do Tratamento
15.
J Am Chem Soc ; 144(11): 4764-4769, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35285232

RESUMO

Sulfone-substituted bicyclo[1.1.0]butanes and housanes have found widespread application in organic synthesis due to their bench stability and high reactivity in strain-releasing processes in the presence of nucleophiles or radical species. Despite their increasing utility, their preparation typically requires multiple steps in low overall yield. In this work, we report an expedient and general one-pot procedure for the synthesis of 1-sulfonylbicyclo[1.1.0]butanes from readily available methyl sulfones and inexpensive epichlorohydrin via the dialkylmagnesium-mediated formation of 3-sulfonylcyclobutanol intermediates. Furthermore, the process was extended to the formation of 1-sulfonylbicyclo[2.1.0]pentane (housane) analogues when 4-chloro-1,2-epoxybutane was used as the electrophile instead of epichlorohydrin. Both procedures could be applied on a gram scale with similar efficiency and are shown to be fully stereospecific in the case of housanes when an enantiopure epoxide was employed, leading to a streamlined access to highly valuable optically active strain-release reagents.


Assuntos
Epicloroidrina , Sulfonas , Butanos , Dimetil Sulfóxido , Indicadores e Reagentes
16.
Alcohol Clin Exp Res ; 46(8): 1384-1396, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35791038

RESUMO

BACKGROUND: Individuals with alcohol use disorder (AUD) exhibit maladaptive responses of the hypothalamic-pituitary-adrenal (HPA) axis to stress, which has been linked to high rates of relapse to drinking among abstinent individuals. Corticotropin-releasing factor (CRF) parvocellular neuroendocrine cells (PNCs) within the paraventricular nucleus of the hypothalamus (PVN) are critical to stress-induced HPA axis activation. Here, we investigate sex differences in synaptic transmission and plasticity in PNCs following the application of the stress-associated neurotransmitter norepinephrine (NE) in a rat model of AUD. METHODS: Adult Sprague-Dawley rats were exposed to 40 days of chronic intermittent ethanol (CIE) vapor and 30 to 108 days of protracted withdrawal. We measured changes in holding current, evoked synaptic currents, and short-term glutamatergic plasticity (STP) in putative PNCs following the application of NE (10 µM) with and without the selective α1 adrenergic receptor (AR) antagonist prazosin (10 µM) or the α2AR antagonist atipamezole (10 µM). The experiments were performed using whole-cell patch clamp recordings in slices from CIE rats and air-exposed controls. RESULTS: NE application caused two distinct effects: a depolarizing, inward, postsynaptic current and a reduction in amplitude of an evoked glutamatergic excitatory postsynaptic current (eEPSC). Both effects were sex- and CIE-specific. Prazosin blocked the postsynaptic inward current, while atipamezole blocked the NE-mediated suppression of eEPSCs. Additionally, STP formation was facilitated following NE application only in stress-naïve males and this response was lost in stressed animals exposed to a 30-min restraint stress following CIE exposure. Furthermore, NE + prazosin restored STP formation in stressed CIE males. CONCLUSIONS: NE exerts excitatory and inhibitory effects on CRF PVN PNCs, and both effects are influenced by sex and CIE. Behavioral and hormonal responses to stress are influenced by STP formation within the PVN, which is lost following CIE and restored with the preapplication of prazosin. The selective blockade of α1AR may, therefore, ameliorate CIE-induced deficits in HPA responses to stress in a sex-specific manner.


Assuntos
Alcoolismo , Sistema Hipotálamo-Hipofisário , Animais , Hormônio Liberador da Corticotropina/metabolismo , Etanol/toxicidade , Feminino , Sistema Hipotálamo-Hipofisário/metabolismo , Hipotálamo/metabolismo , Masculino , Plasticidade Neuronal , Norepinefrina/farmacologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Prazosina/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos alfa , Caracteres Sexuais
17.
Neuroradiology ; 64(8): 1557-1567, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35094103

RESUMO

PURPOSE: Development of a freely available stroke population-specific anatomical CT/MRI atlas with a reliable normalisation pipeline for clinical CT. METHODS: By reviewing CT scans in suspected stroke patients and filtering the AIBL MRI database, respectively, we collected 50 normal-for-age CT and MRI scans to build a standard-resolution CT template and a high-resolution MRI template. The latter was manually segmented into anatomical brain regions. We then developed and validated a MRI to CT registration pipeline to align the MRI atlas onto the CT template. Finally, we developed a CT-to-CT-normalisation pipeline and tested its reliability by calculating Dice coefficient (Dice) and Average Hausdorff Distance (AHD) for predefined areas in 100 CT scans from ischaemic stroke patients. RESULTS: The resulting CT/MRI templates were age and sex matched to a general stroke population (median age 71.9 years (62.1-80.2), 60% male). Specifically, this accounts for relevant structural changes related to aging, which may affect registration. Applying the validated MRI to CT alignment (Dice > 0.78, Average Hausdorff Distance < 0.59 mm) resulted in our final CT-MRI atlas. The atlas has 52 manually segmented regions and covers the whole brain. The alignment of four cortical and subcortical brain regions with our CT-normalisation pipeline was reliable for small/medium/large infarct lesions (Dice coefficient > 0.5). CONCLUSION: The newly created CT-MRI brain atlas has the potential to standardise stroke lesion segmentation. Together with the automated normalisation pipeline, it allows analysis of existing and new datasets to improve prediction tools for stroke patients (free download at https://forms.office.com/r/v4t3sWfbKs ).


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Idoso , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X
18.
Bull Math Biol ; 84(11): 129, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36168001

RESUMO

Absolute concentration robustness (ACR) and concordance are novel concepts in the theory of robustness and stability within Chemical Reaction Network Theory. In this paper, we have extended Shinar and Feinberg's reaction network analysis approach to the insulin signaling system based on recent advances in decomposing reaction networks. We have shown that the network with 20 species, 35 complexes, and 35 reactions is concordant, implying at most one positive equilibrium in each of its stoichiometric compatibility class. We have obtained the system's finest independent decomposition consisting of 10 subnetworks, a coarsening of which reveals three subnetworks which are not only functionally but also structurally important. Utilizing the network's deficiency-oriented coarsening, we have developed a method to determine positive equilibria for the entire network. Our analysis has also shown that the system has ACR in 8 species all coming from a deficiency zero subnetwork. Interestingly, we have shown that, for a set of rate constants, the insulin-regulated glucose transporter GLUT4 (important in glucose energy metabolism), has stable ACR.


Assuntos
Insulina , Modelos Biológicos , Glucose , Proteínas Facilitadoras de Transporte de Glucose , Conceitos Matemáticos
19.
J Stroke Cerebrovasc Dis ; 31(8): 106602, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35724490

RESUMO

BACKGROUND: Recent extended window trials support the benefit of mechanical thrombectomy in anterior circulation large vessel occlusions with clinical-radiographic dissociation. Using trial imaging criteria, 6% were found eligible for MT in the EW in a hub-and-spoke system. We examined the eligibility and outcomes in consecutive extended window-mechanical thrombectomy patients using more pragmatic selection criteria. METHODS: We retrospectively analyzed single-institution data of anterior circulation large vessel occlusions patients presenting between 6-24 h who underwent mechanical thrombectomy based on a priori determined criteria including non-contrast CT head ASPECTS ≥ 6 and/or CTA collateral scores ASITN/SIR 2-4. Primary outcomes consisted of post-mechanical thrombectomy TICI 2b-3 and 3-month modified Rankin scores; safety outcomes consisted of in-hospital mortality and symptomatic intracerebral hemorrhage. RESULTS: 767 consecutive acute ischemic strokes patients presented within the 6-24 hour window, and of these 48 (6%) anterior circulation large vessel occlusions patients underwent mechanical thrombectomy. In this cohort the mean age was 63±17 years, 56% were male, the median NIHSS was 16 [IQR 10-19], the median ASPECTS was 9 (IQR 8-10), and 79% (n=38) had good CTA collaterals. Occlusions were primarily M1 MCA (46%), with 29% tandem occlusions. Successful recanalization (mTICI 2b or 3) was achieved in 73% (n=35), while 6% (n=3) of patients developed symptomatic intracerebral hemorrhage. In-hospital mortality was 25% (n=12) while 40% (n=19) achieved 3-month modified Rankin Scores 0-2. CONCLUSIONS: Our data suggest the use of pragmatic imaging approach of ASPECTS ≥6 with CTA collateral grade in extended time window which is already established in most hospitals.


Assuntos
Isquemia Encefálica , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Trombectomia/efeitos adversos , Trombectomia/métodos
20.
Stroke ; 52(5): 1653-1661, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33611943

RESUMO

Background and Purpose: Multiple studies evaluated whether patent foramen ovale (PFO) closure reduces the risk of ischemic stroke. One commonly reported complication of PFO closure is the development of atrial fibrillation (AF), which is itself a powerful stroke risk factor that requires specific management. This study aims to evaluate the frequency of AF in patients post-percutaneous closure of PFO and the clinical factors that predict AF detection. Methods: Studies were identified by systematically searching EMBASE and MEDLINE databases on July 11, 2019. Meta-analysis of proportions was performed, assuming a random-effects model. Results: A total of 6 randomized controlled trials and 26 observational studies were included, comprising 3737 and 9126 patients, respectively. After PFO closure, the rate of AF development was 3.7 patients per 100 patient-years of follow-up (95% CI, 2.6­4.9). The risk of AF development is concentrated in the first 45 days post-procedure (27.2 patients per 100 patient-years [95% CI, 20.1­34.81], compared with 1.3 patients per 100 patient-years [95% CI, 0.3­2.7]) after 45 days. Meta-regression by age suggested that studies with older patients reported higher rate of AF (P=0.001).In medically treated patients, the rate of AF development was 0.1 per 100 patient-years of follow-up (95% CI, 0.0­0.4). Closure of PFO is associated with increased risk of AF compared with medical management (odds ratio, 5.3 [95% CI, 2.5­11.41]; P<0.001). Conclusions: AF is more common in PFO patients who had percutaneous closure compared with those who were medically treated. The risk of AF was higher in the first 45 days post-closure and in studies that included patients with increased age.


Assuntos
Fibrilação Atrial , Forame Oval Patente , Complicações Pós-Operatórias , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/etiologia , Fibrilação Atrial/fisiopatologia , Forame Oval Patente/epidemiologia , Forame Oval Patente/fisiopatologia , Forame Oval Patente/cirurgia , Humanos , Estudos Observacionais como Assunto , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto
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