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1.
BMC Biotechnol ; 24(1): 28, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38702622

RESUMO

Scientists know very little about the mechanisms underlying fish skin mucus, despite the fact that it is a component of the immune system. Fish skin mucus is an important component of defence against invasive infections. Recently, Fish skin and its mucus are gaining interest among immunologists. Characterization was done on the obtained silver nanoparticles Ag combined with Clarias gariepinus catfish epidermal mucus proteins (EMP-Ag-NPs) through UV-vis, FTIR, XRD, TEM, and SEM. Ag-NPs ranged in size from 4 to 20 nm, spherical in form and the angles were 38.10°, 44.20°, 64.40°, and 77.20°, Where wavelength change after formation of EMP-Ag-NPs as indicate of dark brown, the broad band recorded at wavelength at 391 nm. Additionally, the antimicrobial, antibiofilm and anticancer activities of EMP-Ag-NPs was assessed. The present results demonstrate high activity against unicellular fungi C. albicans, followed by E. faecalis. Antibiofilm results showed strong activity against both S. aureus and P. aeruginosa pathogens in a dose-dependent manner, without affecting planktonic cell growth. Also, cytotoxicity effect was investigated against normal cells (Vero), breast cancer cells (Mcf7) and hepatic carcinoma (HepG2) cell lines at concentrations (200-6.25 µg/mL) and current results showed highly anticancer effect of Ag-NPs at concentrations 100, 5 and 25 µg/mL exhibited rounding, shrinkage, deformation and granulation of Mcf7 and HepG2 with IC50 19.34 and 31.16 µg/mL respectively while Vero cells appeared rounded at concentration 50 µg/mL and normal shape at concentration 25, 12.5 and 6.25 µg/ml with IC50 35.85 µg/mL. This study evidence the potential efficacy of biologically generated Ag-NPs as a substitute medicinal agent against harmful microorganisms. Furthermore, it highlights their inhibitory effect on cancer cell lines.


Assuntos
Biofilmes , Peixes-Gato , Nanopartículas Metálicas , Prata , Nanopartículas Metálicas/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Prata/química , Prata/farmacologia , Animais , Humanos , Muco/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Células Vero , Proteínas de Peixes/farmacologia , Proteínas de Peixes/química , Proteínas de Peixes/metabolismo , Chlorocebus aethiops , Linhagem Celular Tumoral , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Candida albicans/efeitos dos fármacos , Epiderme/metabolismo
2.
Public Health ; 233: 193-200, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38941682

RESUMO

OBJECTIVES: COVID-19 revealed major shortfalls in healthcare workers (HCWs) trained in acute and critical care worldwide, especially in low-resource settings. We aimed to assess mass online courses' efficacy in preparing HCWs to manage COVID-19 patients and to determine whether rapidly deployed e-learning can enhance their knowledge and confidence during a pandemic. STUDY DESIGN: Retrospective cohort study. METHODS: This international retrospective cohort study, led by a large Academic Medical Centre (AMC), was conducted via YouTube and the AMC's online learning platform. From 2020 to 2021, multidisciplinary experts developed and deployed six online training courses based on the latest evidence-based management guidelines. Participants were selected through a voluntary sample following an electronic campaign. Training outcomes were assessed using pre-and post-test questionnaires, evaluation forms, and post-training assessment surveys. Kirkpatrick's Model guided training evaluation to measure self-reported knowledge, clinical skills, and confidence improvement. We also captured the number and type of COVID-19 patients managed by HCWs after the trainings. RESULTS: Every 22.8 reach/impression and every 1.2 engagements led to a course registration. The 10,425 registrants (56.8% female, 43.1% male) represented 584 medical facilities across 154 cities. The largest segments of participants were students/interns (20.6%) and medical officers (13.4%). Of the 2169 registered participants in courses with tests, 66.9% completed post-tests. Test scores from all courses increased from the initial baseline to subsequent improvement post-course. Participants completing post-training assessment surveys reported that the online courses improved their knowledge and clinical skills (83.5%) and confidence (89.4%). Respondents managed over 19,720 COVID-19 patients after attending the courses, with 47.7% patients being moderately/severely ill. CONCLUSIONS: Participants' confidence in handling COVID-19 patients is increased by rapidly deploying mass training to a substantial target population through digital tools. The findings present a virtual education and assessment model that can be leveraged for future global public health issues, and estimates for future electronic campaigns to target.


Assuntos
COVID-19 , Educação a Distância , Pessoal de Saúde , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pessoal de Saúde/educação , Educação a Distância/métodos , Estudos Retrospectivos , Feminino , Masculino , Adulto , Competência Clínica , SARS-CoV-2 , Pessoa de Meia-Idade , Inquéritos e Questionários
3.
Int J Mol Sci ; 23(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36293462

RESUMO

Sperm marking provides a key tool for reproductive biology studies, but it also represents a valuable monitoring tool for genetic pest control strategies such as the sterile insect technique. Sperm-marked lines can be generated by introducing transgenes that mediate the expression of fluorescent proteins during spermatogenesis. The homozygous lines established by transgenesis approaches are going through a genetic bottleneck that can lead to reduced fitness. Transgenic SIT approaches have mostly focused on Dipteran and Lepidopteran pests so far. With this study, we provide sperm-marked lines for the Coleopteran pest model organism, the red flour beetle Tribolium castaneum, based on the ß2-tubulin promoter/enhancer driving red (DsRed) or green (EGFP) fluorescence. The obtained lines are reasonably competitive and were thus used for our studies on reproductive biology, confirming the phenomenon of 'last-male sperm precedence' and that the spermathecae are deployed for long-term sperm storage, enabling the use of sperm from first mating events even after secondary mating events for a long period of time. The homozygosity and competitiveness of the lines will enable future studies to analyze the controlled process of sperm movement into the long-term storage organ as part of a post-mating cryptic female choice mechanism of this extremely promiscuous species.


Assuntos
Besouros , Tribolium , Animais , Masculino , Feminino , Comportamento Sexual Animal , Besouros/genética , Moduladores de Tubulina , Sêmen , Espermatozoides/metabolismo , Tribolium/genética , Biologia
4.
Proc Natl Acad Sci U S A ; 115(24): 6189-6194, 2018 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-29844184

RESUMO

The use of a site-specific homing-based gene drive for insect pest control has long been discussed, but the easy design of such systems has become possible only with the recent establishment of CRISPR/Cas9 technology. In this respect, novel targets for insect pest management are provided by new discoveries regarding sex determination. Here, we present a model for a suppression gene drive designed to cause an all-male population collapse in an agricultural pest insect. To evaluate the molecular details of such a sex conversion-based suppression gene drive experimentally, we implemented this strategy in Drosophila melanogaster to serve as a safe model organism. We generated a Cas9-based homing gene-drive element targeting the transformer gene and showed its high efficiency for sex conversion from females to males. However, nonhomologous end joining increased the rate of mutagenesis at the target site, which resulted in the emergence of drive-resistant alleles and therefore curbed the gene drive. This confirms previous studies that simple homing CRISPR/Cas9 gene-drive designs will be ineffective. Nevertheless, by performing population dynamics simulations using the parameters we obtained in D. melanogaster and by adjusting the model for the agricultural pest Ceratitis capitata, we were able to identify adequate modifications that could be successfully applied for the management of wild Mediterranean fruit fly populations using our proposed sex conversion-based suppression gene-drive strategy.


Assuntos
Sistemas CRISPR-Cas/genética , Evolução Molecular , Genes de Insetos/genética , Controle Biológico de Vetores/métodos , Processos de Determinação Sexual/genética , Animais , Ceratitis capitata/genética , Drosophila melanogaster/genética , Feminino , Edição de Genes , Masculino , Modelos Genéticos
5.
BMC Genet ; 21(Suppl 2): 139, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33339511

RESUMO

BACKGROUND: The invasive fly Drosophila suzukii has become an established fruit pest in Europe, the USA, and South America with no effective and safe pest management. Genetic engineering enables the development of transgene-based novel genetic control strategies against insect pests and disease vectors. This, however, requires the establishment of reliable germline transformation techniques. Previous studies have shown that D. suzukii is amenable to transgenesis using the transposon-based vectors piggyBac and Minos, site-specific recombination (lox/Cre), and CRISPR/Cas9 genome editing. RESULTS: We experienced differences in the usability of piggyBac-based germline transformation in different strains of D. suzukii: we obtained no transgenic lines in a US strain, a single rare transgenic line in an Italian strain, but observed a reliable transformation rate of 2.5 to 11% in a strain from the French Alps. This difference in efficiency was confirmed by comparative examination of these three strains. In addition, we used an attP landing site line to successfully established φC31-integrase-mediated plasmid integration at a rate of 10% and generated landing site lines with two attP sequences to effectively perform φC31-Recombinase Mediated Cassette Exchange (φC31-RMCE) with 11% efficiency. Moreover, we isolated and used the endogenous regulatory regions of Ds nanos to express φC31 integrase maternally to generate self-docking lines for φC31-RMCE. Besides, we isolated the promoter/enhancer of Ds serendipity α to drive the heterologous tetracycline-controlled transactivator (tTA) during early embryonic development and generated a testes-specific tTA driver line using the endogenous beta-2-tubulin (ß2t) promoter/enhancer. CONCLUSION: Our results provide evidence that the D. suzukii strain AM derived from the French Alps is more suitable for piggyBac germline transformation than other strains. We demonstrated the feasibility of using φC31-RMCE in the cherry vinegar fly and generated a set of lines that can be used for highly efficient integration of larger constructs. The φC31-based integration will facilitate modification and stabilization of previously generated transgenic lines that carry at least one attP site in the transgene construction. An early embryo-specific and a spermatogenesis-specific driver line were generated for future use of the binary expression system tet-off to engineer tissue- and stage-specific effector gene expression for genetic pest control strategies.


Assuntos
Drosophila/genética , Engenharia Genética/métodos , Espécies Introduzidas , Animais , Animais Geneticamente Modificados , Elementos de DNA Transponíveis , Feminino , Vetores Genéticos , Células Germinativas , Masculino , Transgenes
6.
Exp Appl Acarol ; 80(3): 349-361, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31927645

RESUMO

Apyrase is one of the essential platelet aggregation inhibitors in hematophagous arthropods due to its ability to hydrolyze ATP and ADP molecules. Here, an apyrase (TNapyrase) with antiplatelet aggregation activity was purified and characterized from the nymphs of the camel tick Hyalomma dromedarii through anion exchange and gel filtration columns. The homogeneity of TNapyrase was confirmed by native-PAGE, SDS-PAGE as well as with isoelectric focusing. Purified TNapyrase had a molecular mass of 25 kDa and a monomer structure. TNapyrase hydrolyzed various nucleotides in the order of ATP > PPi > ADP > UDP > 6GP. The Km value was 1.25 mM ATP and its optimum activity reached at pH 8.4. The influence of various ions on TNapyrase activity showed that FeCl2, FeCl3 and ZnCl2 are activators of TNapyrase. EDTA inhibited TNapyrase activity competitively with a single binding site on the molecule and Ki value of 2 mM. Finally, TNapyrase caused 70% inhibition of ADP-stimulated platelets aggregation and is a possible target for antibodies in future tick vaccine studies.


Assuntos
Apirase/metabolismo , Proteínas de Artrópodes/metabolismo , Agregação Plaquetária , Carrapatos/enzimologia , Animais , Camelus , Ninfa
7.
BMC Biotechnol ; 19(1): 85, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805916

RESUMO

BACKGROUND: The invasive fruit pest Drosophila suzukii was reported for the first time in Europe and the USA in 2008 and has spread since then. The adoption of type II clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) as a tool for genome manipulation provides new ways to develop novel biotechnologically-based pest control approaches. Stage or tissue-specifically expressed genes are of particular importance in the field of insect biotechnology. The enhancer/promoter of the spermatogenesis-specific beta-2-tubulin (ß2t) gene was used to drive the expression of fluorescent proteins or effector molecules in testes of agricultural pests and disease vectors for sexing, monitoring, and reproductive biology studies. Here, we demonstrate an improvement to CRISPR/Cas-based genome editing in D. suzukii and establish a sperm-marking system. RESULTS: To improve genome editing, we isolated and tested the D. suzukii endogenous promoters of the small nuclear RNA gene U6 to drive the expression of a guide RNA and the Ds heat shock protein 70 promoter to express Cas9. For comparison, we used recombinant Cas9 protein and in vitro transcribed gRNA as a preformed ribonucleoprotein. We demonstrate the homology-dependent repair (HDR)-based genome editing efficiency by applying a previously established transgenic line that expresses DsRed ubiquitously as a target platform. In addition, we isolated the Ds_ß2t gene and used its promoter to drive the expression of a red fluorescence protein in the sperm. A transgenic sperm-marking strain was then established by the improved HDR-based genome editing. CONCLUSION: The deployment of the endogenous promoters of the D. suzukii U6 and hsp70 genes to drive the expression of gRNA and Cas9, respectively, enabled the effective application of helper plasmid co-injections instead of preformed ribonucleoproteins used in previous reports for HDR-based genome editing. The sperm-marking system should help to monitor the success of pest control campaigns in the context of the Sterile Insect Technique and provides a tool for basic research in reproductive biology of this invasive pest. Furthermore, the promoter of the ß2t gene can be used in developing novel transgenic pest control approaches and the CRISPR/Cas9 system as an additional tool for the modification of previously established transgenes.


Assuntos
Animais Geneticamente Modificados/genética , Drosophila/genética , Doenças das Plantas/parasitologia , Espermatozoides/citologia , Animais , Animais Geneticamente Modificados/fisiologia , Sistemas CRISPR-Cas , Drosophila/fisiologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Feminino , Edição de Genes , Masculino , Espermatozoides/metabolismo , Transgenes
8.
Andrologia ; 50(3)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29124782

RESUMO

Considerable debate still exists regarding the effects of cigarette smoking on male fertility. This work aimed to explore effects of cigarette smoking on semen parameters and DNA fragmentation on 95 infertile patients who were divided into infertile male nonsmokers (45) and infertile male smokers (50). Smokers were subdivided according to a number of cigarettes smoked per day into mild (≤10), moderate (11-20) and heavy smokers (≥21). Semen analysis, sperm chromatin condensation integrity with aniline blue staining and sperm viability were compared between the study groups. A significant decrease has been shown in sperm count (p = .006), progressive motility (p = <.001), percentage of normal forms (p = <.001) and viability (p = .002) between infertile nonsmoker and infertile smokers. The percentage of abnormal sperm chromatin condensation was significantly higher in smokers compared to nonsmokers (p = <.001). A linear correlation was detected between the extent of cigarette smoking and the degree of worsening in progressive motility (p = .001), total motility (p < .001), viability (p < .001) and normal morphology (p < .001). These results indicate that cigarette smoking has detrimental effects on semen parameters. It negatively affected all conventional semen parameters in addition to sperm chromatin condensation and sperm viability. These abnormalities were also proportional to the number of cigarettes smoked per day and to the duration of smoking.


Assuntos
Cromatina/metabolismo , Fumar Cigarros/efeitos adversos , Nicotiana/toxicidade , Sêmen/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Adulto , Fragmentação do DNA/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Análise do Sêmen , Contagem de Espermatozoides , Espermatozoides/metabolismo , Adulto Jovem
9.
Exp Appl Acarol ; 74(1): 85-97, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29255966

RESUMO

Blood-sucking arthropods have different types of anticoagulants to allow the ingestion of a blood meal from their hosts. In this study, five anticoagulants prolonging the activated partial thromboplastin time were resolved from the salivary gland crude extract of the camel tick Hyalomma dromedarii by chromatography on diethylaminoethyl (DEAE)-cellulose column. They were designated P1, P2, P3, P4 and P5 according to their elution order. P5 was found to be a potent thrombin inhibitor and purified by ultrafiltration through two centrifugal concentrators of 50 and 30 kDa molecular weight cut-off (MWCO), respectively. The camel tick salivary gland thrombin inhibitor was purified 60.6 folds with a specific activity of 564 units/mg protein. It turned out to be homogenous on native-PAGE with molecular weight of 36 kDa as detected on 12% SDS-PAGE. It inhibits bovine thrombin competitively with K i value of 0.55 µM. A task for the future will be the elucidation of this thrombin inhibitor structure to allow its application in thrombosis treatment.


Assuntos
Anticoagulantes/isolamento & purificação , Proteínas de Artrópodes/isolamento & purificação , Ixodidae/fisiologia , Trombina/antagonistas & inibidores , Animais , Anticoagulantes/química , Anticoagulantes/metabolismo , Proteínas de Artrópodes/antagonistas & inibidores , Proteínas de Artrópodes/química , Proteínas de Artrópodes/metabolismo , Bovinos , Feminino , Ixodidae/química
10.
Ann Oncol ; 28(2): 408-414, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27836886

RESUMO

Background: Occupational exposure to acrylamide was associated with excess mortality from pancreatic cancer, though in the absence of dose-risk relationship. Few epidemiological studies have examined the association between acrylamide from diet and pancreatic cancer risk. Patients and methods: We considered this issue in a combined set of 1975 cases of pancreatic cancer and 4239 controls enrolled in six studies of the Pancreatic Cancer Case-Control Consortium (PanC4). We calculated pooled odds ratios (ORs) and their 95% confidence intervals (CI) by estimating study-specific ORs through multivariate unconditional logistic regression models and pooling the obtained estimates using random-effects models. Results: Compared with the lowest level of estimated dietary acrylamide intake, the pooled ORs were 0.97 (95% CI, 0.79-1.19) for the second, 0.91 (95% CI, 0.71-1.16) for the third, and 0.92 (95% CI, 0.66-1.28) for the fourth (highest) quartile of intake. For an increase of 10 µg/day of acrylamide intake, the pooled OR was 0.96 (95% CI, 0.87-1.06), with heterogeneity between estimates (I2 = 67%). Results were similar across various subgroups, and were confirmed when using a one-stage modelling approach. Conclusions: This PanC4 pooled-analysis found no association between dietary acrylamide and pancreatic cancer.


Assuntos
Acrilamida/efeitos adversos , Dieta/efeitos adversos , Neoplasias Pancreáticas/etiologia , Estudos de Casos e Controles , Humanos , Fatores de Risco
11.
Mymensingh Med J ; 26(2): 455-458, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28588187

RESUMO

Primary sclerosing cholangitis (PSC) is a liver disease characterized by inflammation and fibrosis of both intrahepatic and extrahepatic bile ducts resulting in cholestasis. Due to nonspecific symptoms it is difficult to diagnose until complication arises. It is common in male and usually associated with other autoimmune diseases. Here, we report a case of PSC in a young female which was initially thought to be drug induced cholestasis without presence of any other autoimmunity.


Assuntos
Colangite Esclerosante , Ductos Biliares Extra-Hepáticos/fisiopatologia , Colangite Esclerosante/diagnóstico , Feminino , Humanos
12.
Bangladesh Med Res Counc Bull ; 40(2): 74-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26415344

RESUMO

Antinuclear antibody (ANA) is useful in the diagnosis of connective tissue disorder (CTD). Association of specific autoantibodies with the immunofluorescence pattern of ANA in CTD, noted in western literature has been considered as reference in all over the world. However, in Bangladesh no such research work or data correlating the autoantibodies and their ANA patterns is found. Objective of the study was to identify an association between immunofluorescence patterns of antinuclear antibody on HEp-2 cell and more specific antinuclear reactivities (e.g. anti-dsDNA and anti-extractable nuclear antigen) in the serum samples of CTD patients. Serum samples of 152 CTD patients (Systemic lupus erythematosus, Rhumatoid arthritis, Sjogren's syndrome, Systemic sclerosis, Polymyositis, Mixed connective tissue disease) were diagnosed clinically, attending at Bangabandhu Sheikh Mujib Medical University (BSMMU) during the study period of January, 2010 to December, 2010. Samples were subjected for ANA testing by Indirect Immunofluorescence (IIF) on HEp-2 cell (ALPHADIA) in dilution of 1:40, anti-dsDNA by ELISA and anti- extractable nuclear antigen (anti-ENA) by Dot Immunoblot. Dot blot strips were tested for anti-Sm, anti-RNP, anti-SSA/Ro, anti-SSB/La, anti-Scl-70 and anti-Jo-1. Out of 152 patients 110 (72.3%) cases were ANA positive by IIF on HEp-2 cell. ANA positive sera exhibited four fluorescence patterns such as speckled (50.8%), peripheral (21.6%) , homogenous (18.1%) and nucleolar pattern (9%). Peripheral pattern and homogenous pattern was predominantly associated with anti-dsDNA (p < 0.05). Speckled pattern was significantly associated with anti-ENA (p < 0.05).The most commonly identified antinuclear autoreactivity was directed towards anti-RNP (25.7%) then anti-Scl-70 (20%), anti-SSA (14.2%) and anti-SSB (5.7%). Multiple anti-ENA reactivities were identified in 34.28% cases. Peripheral and homogenous pattern is strongly associated with anti-dsDNA and speckled pattern may predict anti-ENA (specially ribonucleoprotiens). As a definite correlation between the ANA patterns and the group of antibodies was detected by dot immunoblot, one could predict presence of certain specific auto antibodies for a particular ANA pattern identified. This may restrict on the cost of laboratory investigations in a developing country like Bangladesh. Thus, ANA-IIF method may reduce the expense of detailed immunological work-up with minimal loss in diagnostic accuracy.


Assuntos
Anticorpos Antinucleares/sangue , Doenças do Tecido Conjuntivo/diagnóstico , Imunofluorescência/métodos , Autoanticorpos/sangue , Bangladesh , Doenças do Tecido Conjuntivo/imunologia , Estudos Transversais , Humanos
13.
Trends Biotechnol ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39327106

RESUMO

Spotted wing Drosophila (Drosophila suzukii Matsumura, or SWD), an insect pest of soft-skinned fruits native to East Asia, has rapidly spread worldwide in the past 15 years. Genetic controls such as sterile insect technique (SIT) have been considered for the environmentally friendly and cost-effective management of this pest. In this review, we provide the latest developments for the genetic control strategies of SWD, including sperm-marking strains, CRISPR-based sex-ratio distortion, neoclassical genetic sexing strains, transgenic sexing strains, a sex-sorting incompatible male system, precision-guided SIT, and gene drives based on synthetic Maternal effect dominant embryonic arrest (Medea) or homing CRISPR systems. These strategies could either enhance the efficacy of traditional SIT or serve as standalone methods for the sustainable control of SWD.

14.
Sci Rep ; 14(1): 22766, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353992

RESUMO

Energy scarcity in the world and the pollutants resulting from excessive use of conventional energy aroused the need for sustainable alternatives that are environment friendly. A multi-use thermoelectric refrigerator powered by solar energy to obtain the lowest consumption with the highest efficiency. The designed refrigerator is based on the Peltier effect using Peltier units where a temperature difference is created between the junctions by applying a voltage difference across the junction. This study investigates the performance of a refrigerator cooling system powered by a photovoltaic (PV) system. The research aims to assess the efficiency, effectiveness, and feasibility of utilizing solar energy to drive refrigeration, particularly in off-grid or environmentally conscious applications. Through a comprehensive experimental setup and data analysis, the study examines energy consumption, cooling efficiency, and overall system performance under varying conditions. The findings contribute valuable insights into the potential of PV-powered refrigerators as sustainable cooling solutions. It relies on a control unit that measures the resulting temperature to determine the appropriate connection mode to give the highest cooling efficiency. The average solar radiation when operating for 8 h, for the different seasons of the year was 149.5, 67.5, 119.3, and 118.3 w/m2 in summer, winter, spring, and fall, respectively. The average cooling energy consumption was 107.25, 137.04, 107, and 138.08 w for temperatures (20 ± 1, 15 ± 1, 20 ± 2, and 15 ± 2) °C respectively that proof solar radiation is sufficient to produce energy for the summer of cooling temperatures up to 15 °C, while in the spring and fall it is sufficient to 20 °C. The Fast not Eco mode is the least energy consuming and the fastest cooling, it can be used for rapid cooling at a short time less than an hour. The best mode in the case of continuous operation is the case of as next Eco mode cooling temperature of 20 ± 0.1 °C. The MATLAB Simulink model was developed to reduce the design cycle and facilitate the integration of solar photovoltaic with the TEC. The optimal operating point is identified through simulation and validated through experimental analysis, the optimal COP was 71.089% by Response surface methodology (RSM).

15.
Artigo em Inglês | MEDLINE | ID: mdl-39472370

RESUMO

The escalating global demand for oil, coupled with declining fossil fuel production, prompts the urgent exploration of renewable alternatives. To address this challenge, researchers are actively seeking environmentally friendly fuels like biodiesel. Among potential feedstocks, oil that is produced from salmon smoking process during industry emerges as a promising option. Smoked salmon oil could be a challenge when producing biodiesel due to its high content of omega-3 compounds. Using homogenous commercial catalyst from alkali to achieve the highest yield from salmon smoking oil was the aim of the current study. A Box-Behnken design and response surface methodology in Design Expert software (version 13) was used to study the effect of four main factors on the biodiesel yield from salmon smoking oil. The optimum biodiesel values were 70°C, 90 min, 0.753 wt.%, and 20 wt.% for temperature, reaction time, sodium hydroxide concentration, and methanol concentration, respectively. At these optimum values, the highest biodiesel production was 92.0% with fatty acid methyl ester contents of 83.4% and conversion efficiency of 77%. Thin-layer chromatography and thermal gravimetric analysis confirmed the successful production of biodiesel at optimized conditions. Using Aspen Plus simulation software confirmed the cost-effectiveness of the homogenous catalyst used for enhancing biodiesel production from salmon smoking oil.

16.
Sci Rep ; 14(1): 4637, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409215

RESUMO

The main aim of this work is to study the main factors affecting the quality of the dried product and the energy requirements through optimizing these factors. To achieve that different drying systems (solar, hybrid solar and oven dryings), layers thickness (1, 2 and 3 cm) and drying temperatures (50, 60 and 70 °C) were used. The obtained results indicated that, the accumulated weight loss of marjoram leaves ranged from 73.22 to 76.9%, for all treatments under study. The moisture content of marjoram leaves ranged from 273.39 to 333.17, 258.02 to 333.04 and 269.38 to 324.90% d.b. for hybrid solar, oven and solar drying systems, respectively. The highest value of the drying rate of marjoram leaves (223.73 gwater kg-1 h-1) was obtained when the marjoram dried by oven drying system at 70 °C at 1 cm layer thickness. The highest values of the basil and marjoram oil content (2.91%) was obtained when the marjoram dried under sun drying system. The energy consumption for drying marjoram decreases with increasing drying temperature and layer thickness for hybrid solar and oven drying systems. The cost of dried marjoram dried under hybrid solar drying system was lower than those of oven drying system, the highest cost (13.48 LE kg-1) was obtained at a temperature of 50 °C and a layer thickness of 1 cm.

17.
J Genet Eng Biotechnol ; 21(1): 7, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689046

RESUMO

BACKGROUND: Thrombin is the most important enzyme in the hemostatic process by permitting rapid and localized coagulation in case of tissue damage. Camel thrombin is the natural and proper target enzyme for the previously purified camel tick salivary gland thrombin inhibitor. RESULTS: In this study, the camel thrombin was purified homogenously in a single affinity chromatographic step on the heparin-agarose affinity column with a specific activity of 3242 NIH units/mg proteins. On SDS-PAGE, the purified camel thrombin contained two forms, 37 kDa α-thrombin and 28 kDa ß-thrombin, and the camel prothrombin was visualized as 72 kDa. The camel thrombin Km value was found out as 60 µM of N-(p-Tosyl)-Gly-Pro-Arg-p-nitroanilide acetate and displayed its optimum activity at pH 8.3. The PMSF was the most potent inhibitor of camel thrombin. Camel tick salivary gland thrombin inhibitor has two binding sites on camel thrombin and inhibited it competitively with Ki value of 0.45 µM. CONCLUSIONS: The purified camel thrombin was found to be more susceptible toward the camel tick salivary gland thrombin inhibitor than bovine thrombin.

18.
Ann Ib Postgrad Med ; 21(3): 96-102, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38706618

RESUMO

Background: Inferior vena cava (IVC) filter placement is an image-guided procedure aimed at primarily preventing pulmonary thromboembolism in patients with lower limb venous thromboembolic (VTE) disease. In Northern Nigeria with a relatively high incidence of thromboembolic disease such as Deep vein thrombosis, reports on IVC filter placement are largely low. We report the feasibility of IVC filter placement on eight patients for the first time in a typical low-resource setting in Northern Nigeria. Case Presentations: We had an equal number of males and females of the eight patients. Their ages ranged from 20 to 80 years. Five patients presented with bilateral lower limbs Deep vein thrombosis (DVT) of which one had a pulmonary embolism. Two other patients had extensive left femoral DVT and one had extensive IVC, iliac, femoral, and popliteal veins thrombosis. The medical records of seven patients, who had IVC filter placement in our department, were reviewed. The IVC filter was deployed with the aid of a C-arm fluoroscopic unit. In a single case, access was secured via an indwelling dialysis catheter. Conclusions: All the patients had successful deployment with satisfactory postprocedure conditions. The intended benefit of pulmonary embolism prevention was achieved in the series of procedures that were performed. Indicating the value of IVC filter even in resource-poor settings and effort should be made towards exploring such intervention.

19.
J Genet Eng Biotechnol ; 21(1): 28, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36884105

RESUMO

BACKGROUND: Glutathione s-transferases (GSTs) perform an essential role in detoxification of xenobiotics and endogenous compounds via their conjugation to reduce glutathione. RESULTS: A GST enzyme, designated tick larvae glutathione S transferase (TLGST), was purified from larvae of the camel tick Hyalomma dromedarii via ammonium sulfate precipitation, glutathione-Sepharose affinity column and Sephacryl S-300 chromatography. TLGST-specific activity was found to be 1.56 Umg-1 which represents 39 folds and 32.2% recovery. The molecular weight of TLGST purified from camel tick larvae was found as 42 kDa by gel filtration. TLGST has a pI value of 6.9 and was found a heterodimeric protein of 28 and 14 kDa subunits as detected on SDS-PAGE. The Lineweaver-Burk plot calculated the km for CDNB to be 0.43 mM with Vmax value of 9.2 Umg-1. TLGST exhibited its optimal activity at pH 7.9. Co2+, Ni2+ and Mn2+ increased the activity of TLGST while Ca2+, Cu2+, Fe2+ and Zn2+ inhibited it. TLGST was inhibited by cumene hydroperoxide, p-hydroxymercuribenzoate, lithocholic acid, hematin, triphenyltin chloride, p-chloromercuribenzoic acid (pCMB), N-p-Tosyl-L-phenylalanine chloromethyl ketone (TPCK), iodoacetamide, EDTA and quercetin. pCMB inhibited TLGST competitively with Ki value of 0.3 mM. CONCLUSIONS: These findings will help to understand the various physiologic conditions of ticks and targeting TLGST could be significant tool for development of prospective vaccines against ticks as a bio-control strategy to overcome the rapid grows in pesticide-resistant tick populations.

20.
Mymensingh Med J ; 32(3): 681-689, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37391960

RESUMO

Wilson disease (WD) is an autosomal recessive disorder of copper metabolism with diverse clinical manifestations. Zinc (Zn) has been used for treatment of WD. Recent studies showed low serum zinc level in patients suffering from WD than the normal. This cross-sectional analytical study has been designed to compare the serum zinc level between paediatric patients suffering from WD but yet not started treatment and children who have normal ALT level. This study was carried out at the Department of Pediatric Gastroenterology and Nutrition, BSMMU, Dhaka, Bangladesh from July 2018 to June 2019. Total 51 children were included in this study. Among them 27 were diagnosed case of WD aged between three to eighteen years and 24 children of same ages who were suffering from other than liver disease having normal ALT were included as volunteers. The patients of WD were divided into four groups according to their presentation as acute hepatitis, chronic liver disease (CLD), acute liver failure & neuropsychiatric manifestation. Informed written consent was obtained from all patients and volunteers for participation in this study. Along with other physical findings and laboratory investigations 3 ml of venous blood were collected for estimation of serum zinc level. After estimation of serum zinc level results were analyzed statistically. The difference in serum zinc levels were compared between the groups. Serum zinc level was significantly lower in Wilson disease patients (43.8±19.7µg/dl; range: 13-83) compared to volunteers group (67.8±11.8µg/dl; range: 47-97) p<0.001. Among the diseased group, serum zinc level were significantly lower in 18 CLD (38.4±17.4µg/dl) and in 4 acute liver failure (33.1±3.7µg/dl) compared to 4 acute hepatitis (71.8±4.3µg/dl) (p=0.001) and (p<0.001) respectively. Mean serum zinc level was low in 4 Wilsonian acute liver failure (33.1±3.7µg/dl), which was significant compared to those (23) who presented as Wilson disease non acute liver failure (45.7±20.8µg/dl) (p=0.013). Serum zinc level was significantly lower in Wilson disease children compared to the volunteers. Zinc level was also found significantly low in Wilson disease presented as CLD and acute liver failure in comparison to Wilson disease presented as acute hepatitis.


Assuntos
Degeneração Hepatolenticular , Falência Hepática Aguda , Humanos , Criança , Pré-Escolar , Adolescente , Bangladesh , Estudos Transversais , Voluntários
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