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Non-Newtonian fluid flow is significant in engineering and biomedical applications such as thermal exchangers, electrical cooling mechanisms, nuclear reactor cooling, drug delivery, blood flow analysis, and tissue engineering. The Caputo operator has emerged as a prevalent tool in fractional calculus, garnering widespread recognition. This research aims to introduce a novel derivative by merging the proportional and Caputo operators, resulting in the fractional operator known as the constant proportional Caputo. In order to demonstrate this newly defined operator's dynamic qualities, it was employed in the analysis of the unsteady Casson flow model. In addition, the current work shows an analytical analysis to determine the Soret effect on the fractionalized MHD Casson fluid over an oscillating vertical plate. Fractional partial differential equations (PDEs) are used to formulate the problem along with IBCs. The introduction of appropriate nondimensional variables converts the PDEs into dimensionless form. The precise solutions to the fractional governing PDEs are then determined by the Laplace transform method. Velocity, concentration, and temperature profiles; the impacts of the Prandtl number; fractional parameter ß and γ; and Soret and Schmidt numbers are graphically depicted. The profiles of temperature, concentration, and velocity rise with rising time and fractional parameters. Interestingly, as the Casson flow parameter is higher, fluid velocity decreases closest to the plate but increases away from the plate. Tables showing the findings for the skin-friction coefficient, Sherwood, and Nusselt numbers for a range of flow-controlling parameter values are provided. Furthermore, an investigation is undertaken to compare fractionalized and ordinary velocity fields. The results suggest that the fractional model employing a constant proportional derivative exhibits a quicker decay than the model incorporating conventional Caputo and Caputo-Fabrizio operators.
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Vaccination is important to prevent cholera. There are limited data comparing anti-O-specific polysaccharide (OSP) and anti-cholera toxin-specific immune responses following oral whole-cell with cholera toxin B-subunit (WC-rBS) vaccine (Dukoral, Valneva) administration in different age groups. An understanding of the differences is relevant because young children are less well protected by oral cholera vaccines than older children and adults. We compared responses in 50 adults and 49 children (ages 2 to <18) who were administered two doses of WC-rBS at a standard 14-day interval. All age groups had significant IgA and IgG plasma-blast responses to the OSP and cholera toxin B-subunit (CtxB) antigens that peaked 7 days after vaccination. However, in adults and older children (ages 5 to <18), antibody responses directed at the OSP antigen were largely IgA and IgG, with a minimal IgM response, while younger children (ages 2 to <5) mounted significant increases in IgM with minimal increases in IgA and IgG antibody responses 30 days after vaccination. In adults, anti-OSP and CtxB memory B-cell responses were detected after completion of the vaccination series, while children only mounted CtxB-specific IgG memory B-cell responses and no OSP-memory B-cell responses. In summary, children and adults living in a cholera endemic area mounted different responses to the WC-rBS vaccine, which may be a result of more prior exposure to Vibrio cholerae in older participants. The absence of class-switched antibody responses and memory B-cell responses to OSP may explain why protection wanes more rapidly after vaccination in young children compared to older vaccinees.IMPORTANCEVaccination is an important strategy to prevent cholera. Though immune responses targeting the OSP of V. cholerae are believed to mediate protection against cholera, there are limited data on anti-OSP responses after vaccination in different age groups, which is important as young children are not well protected by current oral cholera vaccines. In this study, we found that adults mounted memory B-cell responses to OSP, which were not seen in children. Adults and older children mounted class-switched (IgG and IgA) serum antibody responses to OSP, which were not seen in young children who had only IgM responses to OSP. The lack of class-switched antibody responses and memory B-cell responses to OSP in younger participants may be due to lack of prior exposure to V. cholerae and could explain why protection wanes more rapidly after vaccination in young children.
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Vacinas contra Cólera , Cólera , Vibrio cholerae O1 , Adulto , Criança , Humanos , Adolescente , Pré-Escolar , Idoso , Recém-Nascido , Cólera/prevenção & controle , Toxina da Cólera , Antígenos O , Imunoglobulina M , Anticorpos Antibacterianos , Imunoglobulina A , Vacinação , Formação de Anticorpos , Imunoglobulina GRESUMO
Diabetes mellitus is a growing disease that affects people of different ages due to deficiencies in insulin action and secretion. Diabetes causing long-term hyperglycemia damages, destroys, and fails essential organs, including kidneys, eyes, hearts, nerves, and blood vessels. The involvement of pathogenic factors makes diabetes mellitus a severe disease. The autoimmune process results in insulin deficiency by destroying the beta-cells in the pancreas. This leads to insulin resistance. As a result of defects and abnormalities in fat, carbohydrate, and protein synthesis, insulin does not work as it should on the target tissues. As diabetes mellitus becomes, more severe, long-term and effective treatment becomes necessary. A wide range of nanomaterials can be used to treat diabetes mellitus in patients. In addition to being potential imaging, diagnostic, and treatment agents for diabetes mellitus, carbon nanomaterials (CNMs) are another group of nanoparticles that exhibit potential interest. The CNMs acts as implantable nanosensor to track and detect blood glucose level in patients with diabetes. CNMS are possible drug carriers that can treat diabetes mellitus selectively, precisely, and effectively. Diabetes mellitus can be diagnosed and treated with CNMs due to their structural specificity and high drug-loading efficiency. The present review explores CNMs for their types, synthesis, and anti-diabetic properties. This review aims to provide a detailed view of the new technology that can be used to decipher the mechanism of CNMs in diabetes mellitus.
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Diabetes Mellitus , Nanopartículas , Nanoestruturas , Humanos , Carbono/química , Diabetes Mellitus/diagnóstico , Insulina , Nanoestruturas/uso terapêutico , Nanoestruturas/químicaRESUMO
Current health and environmental concerns about the abundance and drawbacks of municipal wastewater as well as industrial effluent have prompted the development of novel and innovative treatment processes. A global shortage of clean water poses significant challenges to the survival of all life forms. For the removal of both biodegradable and non-biodegradable harmful wastes/pollutants from water, sophisticated wastewater treatment technologies are required. Polymer membrane technology is critical to overcoming this major challenge. Polymer matrix-based nanocomposite membranes are among the most popular in polymer membrane technology in terms of convenience. These membranes and their major components are environmentally friendly, energy efficient, cost effective, operationally versatile, and feasible. This review provides an overview of the drawbacks as well as promising developments in polymer membrane and nanocomposite membranes for environmental remediation, with a focus on wastewater treatment. Additionally, the advantages of nanocomposite membranes such as stability, antimicrobial properties, and adsorption processes have been discussed. The goal of this review was to summarize the remediation of harmful pollutants from water and wastewater/effluent using polymer matrix-based nanocomposite membrane technology, and to highlight its shortcomings and future prospects.
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Poluentes Ambientais , Recuperação e Remediação Ambiental , Nanocompostos , Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Água , PolímerosRESUMO
The present focused on comparative study on synthesis of ZnO nanoparticles (ZnO NPs) using chemical method via alkaline precipitation method (ZnO(A) NPs) using NaOH and biogenic method using termite mound extract (ZnO(B) NPs). GC-MS analysis revealed that D-limonene present in termite mound extract might be responsible for the synthesis of ZnO(B) NPs. XRD patterns confirmed hexagonal crystalline structure of ZnO(A) and (B) NPs. Results of antibacterial activity illustrated that ZnO(B) NPs showed its potential against Pseudomonas aeruginosa, ESBL-1, ESBL-2 and EBSL-3. Antibiofilm studies revealed that ZnO(B) NPs exhibited optimum decline in MRSA biofilm formation than ZnO(A) NPs. In addition, ZnO(B) NPs showed potent cytotoxic effect against lung cancer cell lines A549 with IC50 of 35.16 ± 0.10 µg/mL in comparison with ZnO(A) NPs (IC50- 55.09 ± 0.30 µg/mL). Overall, the results revealed that biogenic synthesis of ZnO NPs ensures its biosafety level and enhanced biological activity when compared to chemical synthesis method.
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Nanopartículas Metálicas , Óxido de Zinco , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Extratos Vegetais/química , BiofilmesRESUMO
Aquifers are severely polluted with organic and inorganic pollutants, posing a serious threat to the global ecological system's balance. While various traditional methods are available, the development of innovative methods for effluent treatment and reuse is critical. Polymers have recently been widely used in a variety of industry sectors due to their unique properties. Biopolymers are a biodegradable material that is also a viable alternative to synthetic polymers. Biopolymers are preferably obtained from cellulose and carrageenan molecules from various biological sources. While compared with conventional non-biodegradable polymeric materials, the biopolymer possesses unique characteristics such as renewability, cost-effectiveness, biodegradability, and biocompatibility. The improvements towards the biopolymeric (natural) membranes have also been thoroughly discussed. The use of nanofillers to stabilise and improve the effectiveness of biopolymeric membranes in the elimination of organic pollutants is one of the most recent developments. This was discovered that the majority of biopolymeric membranes technology consolidated on organic pollutants. More research should be directed toward against emerging organic/persistent organic pollutants (POP) and micropollutants. Furthermore, processes for regenerating and reusing utilized biopolymer-based carbon - based materials are emphasized.
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Poluentes Ambientais , Nanofibras , Polímeros , Celulose , BiopolímerosRESUMO
Advanced biochar blended nanoparticles substances, such as nano biochar or nanocomposites, have provided long-term solutions to a wide range of modern-day problems. Biochar blended nano-composites can be created to create better composite materials that combine the benefits of biochar and nanoparticles. Such materials have been typically improved with active functional groups, porous structure, active surface area, catalytic deterioration ability, as well as easy recovery or separation of pollutants. Such biochar-basednanocomposites have good adsorption properties for a variety of pollutants in various form of polluted medium (soil and water contamination). Catalytic nanoparticle encapsulated biochar, can perform concurrently the adsorption (by biochar) as well as catalytic degradation (nanoparticles) functions for pollutants removal from polluted sites. In this review, the advanced and practically feasible techniques involved in the biochar blended nanoparticles-based nanocomposites have been discussed with environmental applications. Furthermore, the mechanisms involved in this composite material in remediation, as well as the advantages and disadvantages of biochar blended nanoparticles-based nanocomposites, were discussed, and future directions for study in this field were suggested.
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Poluentes Ambientais , Recuperação e Remediação Ambiental , Nanocompostos , Nanopartículas , Poluentes do Solo , Poluentes Químicos da Água , Carvão Vegetal/química , Solo , Adsorção , Poluentes Químicos da Água/análiseRESUMO
Nanoparticles synthesis from green chemistry method is gaining a lot of attention due to their non-toxic, low cost and facile. In this study, a copper oxide nanoparticle (CuO NPs) was synthesized using Sida cordifolia aqueous leaf extract and incorporated chitosan biomolecules to potential enhancing of biological properties. The CuO NPs and chitosan (CS) embedded nanocomposite was noted as CuO-CS nanocomposite, its was physicochemical characterized by using of UV-Visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), X-ray Diffraction (XRD) and Field emission scanning electron microscopy (FE-SEM) with Energy dispersive X-ray (EDX) analysis. Bio-functionalized CuO-CS nanocomposite was performed antibacterial efficiency against both Gram positive (Staphylococcus aureus, Bacillus subtilis) and Gram negative (Salmonella typhi, Escherichia coli) bacteria through the Mueller Hinton agar (MHA) well diffusion techniques. The highest bactericidal activity was revealed Gram positive of B. subtilis and Gram negative of S. typhi bacteria, respectively. Further, the cytotoxicity effect of biosynthesized nanocomposite was an examined against human breast cancer MDA-MB-231 and lung cancer A549 cell lines. The half maximal inhibitory concentration is showed at 2 µg/mL for MDA-MB-231and 4 µg/mL was A549 cells. Live/dead cells were detected by fluorescence microscopic observation at the IC50 concentration. In furthermore, bio-functionalized CuO-CS nanocomposite was performed photocatatlytic dye degradation against for industrial dyes of crystal violet (CV) and malachite green (MG). From the results, synergic bio-functionalized CuO-CS nanocomposite was suggested potential suitable for biomedical applications as well as industrial wastewater treatment.
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Quitosana , Neoplasias Pulmonares , Nanopartículas Metálicas , Nanocompostos , Humanos , Quitosana/química , Cobre/química , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química , Bactérias , Neoplasias Pulmonares/tratamento farmacológico , Água , Linhagem Celular , Testes de Sensibilidade Microbiana , Difração de Raios X , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/químicaRESUMO
Nanomaterials have many advantages over bulk materials, including enhanced surface-to-volume proportion as well as magnetic traits. It has been a steady rise in research with using nanomaterials in various biomedical fields in the past few decades. Constructing nanomaterials has emerged as a leading research primary concern in order to discover specialized biomedical applications. Since, their advantageous properties including chemical stability, non-toxicity, bio - compatibility, relatively high magnetization, and strong magnetic vulnerability, nanoparticles of iron oxide had already influenced implementations in different biomedical fields. Nanomaterials can be divided up into four nanomaterials such as metallic nanomaterials, bimetallic or alloy nanomaterials, metal oxide nanomaterials, as well as magnetic nanomaterials. Hence, the purpose of this review is to conduct such in discussion on emerging advancements in nanomaterials for biomedical, with such a special emphasis upon those options of nanomaterials including metallic nanomaterials: Au and Ag, bimetallic nanomaterials: Fe-Co and Fe-Pt, and metal oxides: TiO2 and CeO2. Securing this information gap will result in a better comprehension of the contribution of nanomaterial type and subsequent huge-scale applications in aspects of both their potential and challenges.
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Nanopartículas Metálicas , Nanoestruturas , Nanopartículas Metálicas/toxicidade , Nanoestruturas/toxicidade , ÓxidosRESUMO
The longevity of immune responses induced by different degrees of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection provides information important to understanding protection against coronavirus disease 2019 (COVID-19). Here, we report the persistence of SARS-CoV-2 spike receptor-binding domain (RBD) specific antibodies and memory B cells recognizing this antigen in sequential samples from patients in Bangladesh with asymptomatic, mild, moderate and severe COVID-19 out to six months following infection. Since the development of long-lived memory B cells, as well as antibody production, is likely to be dependent on T helper (Th) cells, we also investigated the phenotypic changes of Th cells in COVID-19 patients over time following infection. Our results show that patients with moderate to severe COVID-19 mounted significant levels of IgG antibodies out to six months following infection, while patients with asymptomatic or mild disease had significant levels of IgG antibodies out to 3 months following infection, but these then fell more rapidly at 6 months than in patients with higher disease severity. Patients from all severity groups developed circulating memory B cells (MBCs) specific to SARS-CoV-2 spike RBD by 3 months following infection, and these persisted until the last timepoint measured at 6 months. A T helper cell response with an effector memory phenotype was observed following infection in all symptomatic patients, while patients with asymptomatic infection had no significant increases in effector Th1, Th2 and Th17 effector memory cell responses. Our results suggest that the strength and magnitude of antibody and memory B cells induced following SARS-CoV-2 infection depend on the severity of the disease. Polarization of the Th cell response, with an increase in Th effector memory cells, occurs in symptomatic patients by day 7 following infection, with increases seen in Th1, Th2, Th17 and follicular helper T cell subsets.
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COVID-19 , Humanos , Bangladesh/epidemiologia , Células B de Memória , SARS-CoV-2 , Imunoglobulina G , Anticorpos Antivirais , Gravidade do Paciente , Células Th17RESUMO
Coronavirus disease 2019 (COVID-19) is a protean disease causing different degrees of clinical severity including fatality. In addition to humoral immunity, antigen-specific T cells may play a critical role in defining the protective immune response against SARS-CoV-2, the virus that causes this disease. As a part of a longitudinal cohort study in Bangladesh to investigate B and T cell-specific immune responses, we sought to evaluate the activation-induced marker (AIM) and the status of different immune cell subsets during a COVID-19 infection. We analyzed a total of 115 participants, which included participants with asymptomatic, mild, moderate, and severe clinical symptoms. We observed decreased mucosal-associated invariant T (MAIT) cell frequency on the initial days of the COVID-19 infection in symptomatic patients compared to asymptomatic patients. However, natural killer (NK) cells were found to be elevated in symptomatic patients just after the onset of the disease compared to both asymptomatic patients and healthy individuals. Moreover, we found a significant increase of AIM+ (both OX40+CD137+ and OX40+CD40L+) CD4+ T cells in moderate and severe COVID-19 patients in response to SARS-CoV-2 peptides (especially spike peptides) compared to pre-pandemic controls who are unexposed to SARS-CoV-2. Notably, we did not observe any significant difference in the CD8+ AIMs (CD137+CD69+), which indicates the exhaustion of CD8+ T cells during a COVID-19 infection. These findings suggest that patients who recovered from moderate and severe COVID-19 were able to mount a strong CD4+ T-cell response against shared viral determinants that ultimately induced T cells to mount further immune responses to SARS-CoV-2.
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COVID-19 , Bangladesh/epidemiologia , Ligante de CD40 , Linfócitos T CD8-Positivos , Humanos , Imunidade Humoral , Estudos Longitudinais , SARS-CoV-2 , Índice de Gravidade de DoençaRESUMO
This study aims to identify blood biomarkers for rapidly predicting progression and severity assessment of COVID-19 in type 2 diabetic (DM) and non-DM (NDM) patients. Among 211 hospitalized patients suspected of COVID-19, 98 were confirmed COVID-19 by rRT-PCR. The COVID-19 positive group contained 58 DM and 40 NDM patients with total death 9 of which 7 were males and 6 were DM, indicating males and DM individuals as more susceptible to COVID-19. Blood biomarkers notably serum ferritin, CRP, D-dimer, ALT, troponin I, and Hb1Ac were significantly (p < 0.05) higher in COVID-19 patients. Ferritin and HbA1c levels were significantly (p < 0.05) higher in DM than NDM COVID-19 patients. The present study suggests that ferritin and HbA1c levels for DM patients, and ferritin, D-dimer, ALT for NDM patients could be routinely used as biomarkers for progression and severity assessment of COVID-19. CRP and Troponin-I could be the predictor only for poor prognosis of COVID-19.
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COVID-19 , Diabetes Mellitus , Biomarcadores , COVID-19/diagnóstico , Estudos Transversais , Feminino , Ferritinas , Hemoglobinas Glicadas , Humanos , Masculino , SARS-CoV-2RESUMO
The coronavirus disease 2019 (COVID-19), a pandemic declared by the World Health Organization on March 11, 2020, is caused by the infection of highly transmissible species of a novel coronavirus called severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). As of July 25, 2021, there are 194,372,584 cases and 4,167,937 deaths with high variability in clinical manifestations, disease burden, and post-disease complications among different people around the globe. Overall, COVID-19 is manifested as mild to moderate in almost 90% of the cases and only the rest 10% of the cases need hospitalization. However, patients with older age and those having different comorbidities have made worst the pandemic scenario. The variability of pathological consequences and clinical manifestations of COVID-19 is associated with differential host-SARS-CoV-2 interactions, which are influenced by the factors that originated from the SARS-CoV-2 and the host. These factors usually include the genomic attributes and virulent factors of the SARS-CoV-2, the burden of coinfection with other viruses and bacteria, age and gender of the individuals, different comorbidities, immune suppressions/deficiency, genotypes of major histocompatibility complex, and blood group antigens and antibodies. We herein retrieved and reviewed literatures from PubMed, Scopus, and Google relevant to clinical complications and pathogenesis of COVID-19 among people of different age, sex, and geographical locations; genomic characteristics of SARS-CoV-2 including its variants, host response under different variables, and comorbidities to summarize the dynamics of the host response to SARS-CoV-2 infection; and host response toward approved vaccines and treatment strategies against COVID-19. After reviewing a large number of published articles covering different aspects of host response to SARS-CoV-2, it is clear that one aspect from one region is not working with the scenario same to others, as studies have been done separately with a very small number of cases from a particular area/region of a country. Importantly, to combat such a pandemic as COVID-19, a conclusive understanding of the disease dynamics is required. This review emphasizes on the identification of the factors influencing the dynamics of host responses to SARS-CoV-2 and offers a future perspective to explore the molecular insights of COVID-19.
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Cholera remains a major public health problem in resource-limited countries. Vaccination is an important strategy to prevent cholera, but currently available vaccines provide only 3 to 5 years of protection. Understanding immune responses to cholera antigens in naturally infected individuals may elucidate which of these are key to longer-term protection seen following infection. We recently identified Vibrio cholerae O1 sialidase, a neuraminidase that facilitates binding of cholera toxin to intestinal epithelial cells, as immunogenic following infection in two recent high-throughput screens. Here, we present systemic, mucosal, and memory immune responses to sialidase in cholera index cases and evaluated whether systemic responses to sialidase correlated with protection using a cohort of household contacts. Overall, we found age-related differences in antisialidase immune response following cholera. Adults developed significant plasma anti-sialidase IgA, IgG, and IgM responses following infection, whereas older children (≥5 years) developed both IgG and IgM responses, and younger children only developed IgM responses. Neither older children nor younger children had a rise in IgA responses over the convalescent phase of infection (day 7/day 30). On evaluation of mucosal responses and memory B-cell responses to sialidase, we found adults developed IgA antibody-secreting cell (ASC) and memory B-cell responses. Finally, in household contacts, the presence of serum anti-sialidase IgA, IgG, and IgM antibodies at enrollment was associated with a decrease in the risk of subsequent infection. These data show cholera patients develop age-related immune responses against sialidase and suggest that immune responses that target sialidase may contribute to protective immunity against cholera.IMPORTANCE Cholera infection can result in severe dehydration that may lead to death within a short period of time if not treated immediately. Vaccination is an important strategy to prevent the disease. Oral cholera vaccines provide 3 to 5 years of protection, with 60% protective efficacy, while natural infection provides longer-term protection than vaccination. Understanding the immune responses after natural infection is important to better understand immune responses to antigens that mediate longer-term protection. Sialidase is a neuraminidase that facilitates binding of cholera toxin to intestinal epithelial cells. We show here that patients with cholera develop systemic, mucosal, and memory B-cell immune responses to the sialidase antigen of Vibrio cholerae O1 and that plasma responses targeting this antigen correlate with protection.
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Anticorpos Antibacterianos/sangue , Cólera/imunologia , Cólera/prevenção & controle , Memória Imunológica , Neuraminidase/imunologia , Vibrio cholerae O1/enzimologia , Vibrio cholerae O1/imunologia , Adolescente , Adulto , Fatores Etários , Células Produtoras de Anticorpos/imunologia , Linfócitos B/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina A/análise , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Aquaporins (AQPs) are integral membrane proteins and found in all living organisms from bacteria to human. AQPs mainly involved in the transmembrane diffusion of water as well as various small solutes in a bidirectional manner are widely distributed in various human tissues. Human contains 13 AQPs (AQP0-AQP12) which are divided into three sub-classes namely orthodox aquaporin (AQP0, 1, 2, 4, 5, 6, and 8), aquaglyceroporin (AQP3, 7, 9, and 10) and super or unorthodox aquaporin (AQP11 and 12) based on their pore selectivity. Human AQPs are functionally diverse, which are involved in wide variety of non-infectious diseases including cancer, renal dysfunction, neurological disorder, epilepsy, skin disease, metabolic syndrome, and even cardiac diseases. However, the association of AQPs with infectious diseases has not been fully evaluated. Several studies have unveiled that AQPs can be regulated by microbial and parasitic infections that suggest their involvement in microbial pathogenesis, inflammation-associated responses and AQP-mediated cell water homeostasis. This review mainly aims to shed light on the involvement of AQPs in infectious and non-infectious diseases and potential AQPs-target modulators. Furthermore, AQP structures, tissue-specific distributions and their physiological relevance, functional diversity and regulations have been discussed. Altogether, this review would be useful for further investigation of AQPs as a potential therapeutic target for treatment of infectious as well as non-infectious diseases.
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Alkaline proteases having activity and stability at alkaline pH possess a large variety of applications in many industries. Growing renewed interest urges the need to find a single alkaline protease with promising properties to be used in different industrial processes. Herein, alkaline proteases produced through fermentation of cheap and easily available organic municipal solid wastes by Bacillus subtilis AKAL7 and Exiguobacterium indicum AKAL11 were purified to investigate their kinetic and thermodynamic parameters, detergent compatibility, dehairing and feather-degrading capability. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed that the purified protease from B. subtilis and E. indicum had molecular mass of â¼45 and 75 kDa, respectively. The protease from B. subtilis and E. indicum showed highest activity at 55 and 50 °C having low K m 1.17 and 0.567 mg/mL and high V max 416.67 and 333.33 µmole/min, respectively. The activation energy and temperature quotient of protease from B. subtilis and E. indicum were 26.52 and 65.75 kJ/mole, and 1.0004 and 1.0003 at 20-55 and 20-50 °C, respectively. Thermodynamics analysis revealed the formation of more ordered enzyme-substrate complexes along with spontenity of enzyme reaction. The protease from E. indicum exhibited better compatibility at higher concentration of detergents compared to that from B. subtilis. However, both proteases could retain more than 80% of the activity in the presence of 0.1% commercial laundry detergents. The purified protease from the both sources could degrade almost 90% of barbs and 40% of dry weight of the native feather and that from E. indicum could dehair cow skin. Results reported herein suggest that the alkaline protease from B. subtilis AKAL7 and E. indicum AKAL11 has biotechnological implications in detergent, leather and poultry feather processing industries.
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Bacillales/enzimologia , Bacillus subtilis/enzimologia , Proteínas de Bactérias/metabolismo , Endopeptidases/metabolismo , Resíduos Sólidos , Animais , Detergentes/química , Estabilidade Enzimática , Exiguobacterium , Plumas , Fermentação , Cinética , Peso Molecular , TemperaturaRESUMO
We have earlier reported that a single dose of oral cholera vaccine (OCV) is protective in adults and children ≥5 years of age and sustained for 2 years. We enrolled participants (n = 240) from this study, between March-September 2017, over 3 years after receiving a primary single dose. Immune responses were measured in placebo group (Primary Immunization group: PI) and compared with those who received a single dose (Booster Immunization group: BI). The children were 4 to <5 years, 5 to <18 years and adults >18 years. Blood was collected at day 0 (before vaccination) and after receiving 1st and 2nd doses of OCV. Overall, the BI and PI groups showed vibriocidal antibody response after 1st and 2nd dose of vaccination in all age groups to V. cholerae O1 and O139. Young children in the BI group showed significantly higher vibriocidal antibody response two weeks after receiving the first dose as compared to PI group to LPS. Elevated plasma IgA responses to LPS after the first dose were observed among the BI group compared to the PI group among the young children. Mucosal antibody responses measured in fecal extracts showed similar increases as that of vibriocidal and LPS responses in the BI group. These results suggest a single boosting dose of OCV generated immune response in primed population >5 years of age who had earlier received OCV. However, young children who had received OCV earlier, boosting after a single dose, resulted in increased immune responses compared to the PI group. Further studies are needed to assess protection obtained from different strategies, especially for young children and to determine the numbers of primary and booster doses needed. In addition, more information is needed regarding the optimum interval between primary and booster doses to plan future interventions for cholera control. ClinicalTrials.gov Identifier: NCT02027207.
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Vacinas contra Cólera/imunologia , Cólera , Imunização Secundária , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , Cólera/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vacinação , Adulto JovemRESUMO
BACKGROUND: Oral cholera vaccine (OCV) containing killed Vibrio cholerae O1 and O139 organisms (Bivalent-OCV; Biv-OCV) are playing a central role in global cholera control strategies. OCV is currently administered in a 2-dose regimen (day 0 and 14). There is a growing body of evidence that immune responses targeting the O-specific polysaccharide (OSP) of V. cholerae mediate protection against cholera. There are limited data on anti-OSP responses in recipients of Biv-OCV. We assessed serum antibody responses against O1 OSP, as well as antibody secreting cell (ASC) responses (a surrogate marker for mucosal immunity) and memory B cell responses in blood of adult recipients of Biv-OCV in Dhaka, Bangladesh. METHODOLOGY/PRINCIPAL FINDINGS: We enrolled 30 healthy adults in this study and administered two doses of OCV (Shanchol) at days 0 and 14. Blood samples were collected before vaccination (day 0) and 7 days after each vaccination (day 7 and day 21), as well as on day 44. Serum responses were largely IgA with minimal IgG and IgM responses in this population. There was no appreciable boosting following day 14 vaccination. There were significant anti-OSP IgA ASC responses on day 7 following the first vaccination, but none after the second immunization. Anti-OSP IgA memory B cell responses were detectable 30 days after completion of the vaccination series, with no evident induction of IgG memory responses. In this population, anti-Ogawa OSP responses were more prominent than anti-Inaba responses, perhaps reflecting impact of previous exposure. Serum anti-OSP responses returned to baseline within 30 days of completing the vaccine series. CONCLUSION: Our results call into question the utility of the 2-dose regimen separated by 14 days in adults in cholera endemic areas, and also suggest that Biv-OCV-induced immune responses targeting OSP are largely IgA in this highly endemic cholera area. Studies in children in cholera-endemic areas need to be performed. Protective efficacy that extends for more than a month after vaccination presumably is mediated by direct mucosal immune response which is not assessed in this study. Our results suggest a single dose of OCV in adults in a cholera endemic zone may be sufficient to mediate at least short-term protection.
Assuntos
Formação de Anticorpos , Vacinas contra Cólera/imunologia , Cólera/prevenção & controle , Memória Imunológica/imunologia , Mucosa/imunologia , Antígenos O/imunologia , Vacinação , Vibrio cholerae O1/imunologia , Administração Oral , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Células Produtoras de Anticorpos/imunologia , Linfócitos B/imunologia , Bangladesh , Vacinas contra Cólera/administração & dosagem , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Vibrio cholerae O139/imunologia , Adulto JovemRESUMO
Bacteria were isolated from effluents of textile industries and screened by their capability to decolorize at least one of eight reactive dyes used in the textile industries. Three isolates having the capability to decolorize the highest number of dyes with more than 25% of decolorization were identified as Alcaligenes faecalis AZ26, Bacillus cereus AZ27 and Bacillus sp. AZ28 based on morphological, cultural, biochemical characteristics, and 16S rDNA sequence analysis. The decolorization capability of these three bacterial isolates was optimized under different physicochemical conditions by using Novacron Super Black G (NSB-G), one of the eight reactive dyes commonly used in textile industries. These bacterial isolates grew well in the presence of up to 500 mg L-1 of NSB-G and showed decolorization of approximately 90% at 200 mg L-1 of NSB-G after 96 h of cultivation at 37 °C and pH 8.0 under static condition. Decolorization of NSB-G by the bacterial isolates was investigated using UV-VIS spectrophotometry and Fourier Transform Infrared Spectroscopy (FTIR) analysis. The UV-visible absorbance spectra and the FTIR spectrum of the decolorized NSB-G significantly differed from those of the parent dye, indicating that the NSB-G was degraded by the bacterial isolates. High decolorization extent supports the notion that the bacterial isolates reported herein might have potential in the biological treatment of dyeing mill effluents.
RESUMO
Alkaline proteases have applications in numerous industries. In this study, we have isolated and screened proteolytic bacteria from poultry wastes mixed soil and identified two bacterial isolates as Bacillus subtilis AKAL7 and Exiguobacterium indicum AKAL11 based on 16S rDNA sequencing. Maximum level of protease production was achieved after 24 h of fermentation in a basal medium. The optimal temperature, initial pH of the media and agitation for alkaline protease production by these two isolates were 30 °C, pH 9.0 and 120 rpm, respectively. The both bacterial isolates produced maximum level of protease with 3.0% organic municipal solid wastes (OMSW) as the sole source of carbon and nitrogen under previously optimized fermentation conditions. In comparison with the shake flask, protease production increased about 2.5-fold in the bioreactor with reduction in fermentation period. The partial purification of protease resulted in a final 45.67 and 34.86-fold purified protease with a specific activity of 8335.34 and 9918.91 U/mg protein and a typical yield of 9.75 and 9.41% from B. subtilis and E. indicum, respectively. The optimum temperature and pH of the partially purified protease from the both sources was 40 °C and pH 9.0, respectively. Protease from the both isolates was stable at pH 7.0-12.0 and at temperatures up to 50 °C. The effects of protease inhibitors indicated that the protease from B. subtilis might be serine and cysteine type and from E. indicum might be cysteine type. Mg2+, K+ and Ca2+ stimulated but Zn2+, Hg2+, Co2+ and Fe3+ strongly inhibited the protease activity. The partially purified protease from B. subtilis substantially dehaired cow skin and decomposed gelatinous compound from X-ray film. Our study revealed that OMSW can be used as raw material for production of bacterial extracellular protease and alkaline protease from B. subtilis might be potential for industrial and biotechnological applications.