Journal of Pathogens最新文献

{"title":"Fermented Polyherbal Formulation Restored Ricinoleic Acid-Induced Diarrhea in Sprague Dawley Rats and Exhibited <i>In Vitro</i> Antibacterial Effect on Multiple Antibiotic-Resistant Gastrointestinal Pathogens.","authors":"Subhanil Chakraborty, Babli Roy, Subhajit Sen, Santi M Mandal, Arghya Das, Ranadhir Chakraborty","doi":"10.1155/2024/1997064","DOIUrl":"https://doi.org/10.1155/2024/1997064","url":null,"abstract":"<p><p>The involvement of multiple antibiotic-resistant gastrointestinal pathogens in diarrhea aggravates the disease condition uncontrollably. The current study aimed to find and develop a suitable formulation utilizing multiple natural components from known plant sources to augment the current therapeutic outcomes. The hydroethanolic extraction method was applied through boiling and fermentation on ancient observation-based efficacious plant parts for developing the antidiarrheal polyherbal formulation AP-01. An animal study model of diarrhea was used to evaluate the safety and efficacy of the formulation. The formulation was tested <i>in vitro</i> on four different multiple antibiotic-resistant gastrointestinal pathogens collected from the national repository. The formulation depicted no cytotoxicity on normal gut cells and was efficacious at 10 ml/kg single dose in relieving symptoms of diarrhea by 79.71%, compared with the standard drug showing a reduction of symptoms by 83.01%. AP-01 exhibited delayed gastric motility. The symptoms of diarrhea ceased to occur within 320.66 ± 5.05 minutes with AP-01, whereas the standard drug took 308 ± 6.63 minutes. AP-01 was found successful at a viable dosage regimen of 75 <i>μ</i>l/ml v/v to 100 <i>μ</i>l/ml v/v in inhibiting the growth of different pathogens from the Enterobacteriaceae family possessing resistance against several classes of antibiotics in culture media. Chemical analysis revealed different alkaloids, flavonoids, and polyphenols that probably work in unison through multiple modes of action to arrest diarrhea and inhibit pathogens simultaneously. These promising results shown by AP-01 should evoke an effort to dive deep into research and development for better therapeutic formulations for infectious diarrhea by harvesting nature's arsenal.</p>","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"2024 ","pages":"1997064"},"PeriodicalIF":1.1,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11458275/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142391366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Establishment of a <i>STING</i>-Deficient HepG2 Cell Line through CRISPR/Cas9 System and Evaluation of Its Effects on <i>Salmonella</i> Replication.","authors":"Lanqing Sun, Kai Huang, Xuan Huang","doi":"10.1155/2024/9615181","DOIUrl":"https://doi.org/10.1155/2024/9615181","url":null,"abstract":"<p><strong>Background: </strong><i>Salmonella enterica</i> serovar Typhimurium (<i>Salmonella</i> Typhimurium) is a common food-borne pathogen that causes gastroenteritis and can lead to life-threatening systemic disease when it spreads to vital organs, such as the liver. Stimulator of interferon genes (STING) is a crucial regulator of the host's innate immune response to viral infections, while its role in bacterial infections remains controversial. This study aims to establish a <i>STING</i>-deficient HepG2 cell line through the CRISPR/Cas9 system and evaluate its effects on <i>Salmonella</i> replication.</p><p><strong>Methods: </strong>In this study, a <i>STING</i> knockout HepG2 cell line was constructed through the application of CRISPR/Cas9 technology. We assessed cell viability and proliferation using the CCK-8 assay. Subsequently, we investigated the effect of <i>STING</i> deletion on <i>Salmonella</i> replication and the expression of type I interferon-related genes.</p><p><strong>Results: </strong>The <i>STING</i> knockout HepG2 cell line was successfully constructed using the CRISPR/Cas9 system. The proliferation capability was diminished in <i>STING</i>-deficient HepG2 cells, while <i>Salmonella</i> Typhimurium replication in these cells was augmented compared to the wild-type (WT) group. Following <i>Salmonella</i> infection, the transcriptional responses of type I interferon-related genes, such as <i>IFNB1</i> and <i>ISG15</i>, were inhibited in <i>STING</i>-deficient HepG2 cells.</p><p><strong>Conclusions: </strong>We successfully constructed a <i>STING</i>-deficient cell line. Our finding of increased <i>Salmonella</i> Typhimurium replication in <i>STING</i>-deficient HepG2 cells provides the basis for further studies on pathogen-host interactions.</p>","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"2024 ","pages":"9615181"},"PeriodicalIF":1.1,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11412752/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142289739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of Biofilm Production and Antibiotic Susceptibility Pattern among Clinically Isolated <i>Staphylococcus aureus</i>.","authors":"Sushant Pokhrel, Namrata Sharma, Suraj Aryal, Rachita Khadka, Tika Bahadur Thapa, Pawan Pandey, Govardhan Joshi","doi":"10.1155/2024/2342468","DOIUrl":"10.1155/2024/2342468","url":null,"abstract":"<p><strong>Aim: </strong>The increasing antibiotic resistance and the ability to form biofilms in medical devices have become the leading cause of severe infections associated with <i>Staphylococcus aureus</i> (<i>S. aureus</i>). Since the bacteria living in biofilms can exhibit 10- to 1,000-fold increase in antibiotic resistance and implicate chronic infectious diseases, the detection of <i>S. aureus</i> ability to form biofilms is of great importance for managing, minimizing, and effectively treating infections caused by it. This study aimed to compare the tube and tissue culture methods to detect biofilm production and antibiotic susceptibility in MRSA and MSSA.</p><p><strong>Materials and methods: </strong>The <i>S. aureus</i> isolates were identified by the examination of the colony morphology, Gram staining, and various biochemical tests. Antimicrobial susceptibility testing of all isolates was performed by the modified Kirby-Bauer disc diffusion method as recommended by CLSI guidelines. MRSA screening was performed phenotypically using a cefoxitin disc (30 <i>µ</i>g). Isolates were tested for inducible resistance using the D-test, and two phenotypic methods detected biofilm formation.</p><p><strong>Results: </strong>Among 982 nonrepeated clinical specimens, <i>S. aureus</i> was isolated from 103 (10.48%). Among 103 clinical isolates of <i>S. aureus</i>, 54 (52.42%) isolates were MRSA, and 49 (47.57%) were MSSA. Among 54 MRSA isolates, the inducible MLSB phenotype was observed in 23/54 (42.59%) with a positive D-test. By TCP method, 26 (48.1%) MRSA isolates were strong biofilm producers, whereas, among all MSSA isolates, only 6 (12.2%) were strong biofilm producers.</p><p><strong>Conclusion: </strong>MRSA showed strong biofilm production in comparison with MSSA. The TCP method is a recommended reliable method to detect the biofilm among <i>S. aureus</i> isolates, and the TM method could be useful for the screening of biofilm production in <i>S. aureus</i> in the routine clinical laboratory.</p>","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"2024 ","pages":"2342468"},"PeriodicalIF":2.6,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11090675/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140922504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seroprevalence of Human Brucellosis among Syrian Refugees in Jordan, 2022","authors":"Tarek Al-Sanouri, Yousef Khader, Ekhlas Hailat, Sereen Iweir, Mohammad Abu Khudair, M. Al Nsour","doi":"10.1155/2023/5885316","DOIUrl":"https://doi.org/10.1155/2023/5885316","url":null,"abstract":"Introduction. Brucellosis is prevalent in Mediterranean countries. The aim of this study was to determine the seroprevalence of brucellosis and associated factors among Syrian refugees in Jordan. Methods. A cross-sectional study was conducted among adult Syrian refugees who attended the Public Health Lab (PHL) in Al Mafraq governorate, during the period of May-June 2022 to obtain a health certificate, which is legally required to receive governmental authorization for employment in Jordan. Blood samples were obtained from participants and a serum specimen was tested for the presence of IgG antibodies against Brucella using enzyme-linked immunosorbent assay (ELISA) IgG kits (Vircell Microbiologists, Granada, Spain). Results. A total of 1562 Syrian refugees were enrolled in the study. Their ages ranged between 18 and 74 years, with a median age of 30 years at presentation. The majority were males (75.9%, n = 1186) and 24.1% (n = 376) were females. The Brucella ELISA IgG results were positive for 149 persons, with an overall seroprevalence rate of 9.5% (95% confidence interval: 8.0%–11.0%). Having animal-related occupations, residing outside refugee camps, consuming unpasteurized milk, handling animals or their tissues, and slaughtering animals within 6 months of study inclusion were significantly higher among the seropositive group. In the multivariate analysis, IgG-positive persons were 13 times more likely to report being diagnosed with brucellosis (OR = 13.1, 95% CI: 6.1–28.3; \u0000 \u0000 p\u0000 \u0000  ≤ 0.001). In addition, they were more likely to reside in the city of Al Mafraq, as opposed to a refugee camp (OR = 1.9, 95% CI: 1.1–3.2; \u0000 \u0000 p\u0000 \u0000  = 0.025) and to have handled animals within 6 months of study inclusion (OR = 3.1, 95% CI: 1.1–8.9; \u0000 \u0000 p\u0000 \u0000  = 0.035). Conclusions. In conclusion, one-tenth of adult Syrian refugees were tested positive for Brucella ELISA IgG. Being diagnosed with brucellosis, residing in the city of Al Mafraq, as opposed to a refugee camp, and handling animals within 6 months of study inclusion were significantly associated with being positive for Brucella ELISA IgG. This study illustrates the need for improved brucellosis control measures via comprehensive vaccination of animals and enhanced laboratory detection and surveillance capacities, in addition to emphasizing the need for increased awareness sessions among Syrian refugees on the safe use and preparation of dairy products and safety practices of handling animals and their tissues.","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"44 10","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138967021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of Escherichia coli Isolated from Intestinal Microbiota Children of 0–5 Years Old in the Commune of Abomey-Calavi","authors":"H. Sina, D. Dah-Nouvlessounon, T. Adjobimey, Bawa Boya, Ghislaine M. C. Dohoue, C. N’tcha, Violette Chidikofan, F. Baba-Moussa, I. Abdoulaye, A. Adjanohoun, L. Baba-Moussa","doi":"10.1155/2022/6253894","DOIUrl":"https://doi.org/10.1155/2022/6253894","url":null,"abstract":"Escherichia coli is a commensal bacterium and one of the first bacteria to colonize the digestive tract of newborns after birth. It is characterized by great versatility and metabolic flexibility that allows its survival in different niches. The present study aims at analyzing the diversity of E. coli strains isolated from the intestinal microbiota of children aged from 0 to 5 years in the commune of Abomey-Calavi in Benin. For this purpose, a descriptive and analytical cross-sectional study was conducted. A total of 135 stool samples were collected from the pediatric clinic of Abomey-Calavi. Microbiological analyses were performed according to standard microbiology analytical techniques. The molecular characterization of E. coli was performed by investigating eight genes (dinB, icdA, pabB, polB, putP, trpA, trpB, and uidA) using the PCR technique. The results showed that the average loading rate on stool samples was 3.74 × 107 CFU/g for TAMF. A total of 7 species of bacteria were identified at different proportions: Staphylococcus spp (55.36%), E. coli (14.29%), Klebsiella ornithinolytica (12.5%), Serratia odorifera (5.36%), and Enterobacter aerogenes (5.36%). Interestingly, isolated E. coli presented a resistance of 100% to cefotaxime and aztreonam. In addition, resistances of 95.24% and 50% were observed against erythromycin and nalidixic acid, respectively. The molecular characterization of the isolated E. coli strains allowed us to discover another molecular variation within the isolated strains. Genes encoding the enzymes isocitrate dehydrogenase (icd) and DNA polymerase II (polB) were detected at 96.30% in the isolated E. coli strains. Moreover, the genes encoding the enzymes beta-D-glucuronidase (uidA) and DNA polymerase (dinB) were detected at 88.89% in the isolated E. coli strains. Interestingly, 81.48%, 85.19, 92.59%, and 100% of isolated E. coli strains expressed the genes encoding the enzymes tryptophan synthase subunit A (trpA), proline permease (putP), p-aminobenzoate synthase, and tryptophan synthase subunit B (trpB), respectively. The diversity of E. coli strains reflects the importance of regulatory mechanisms in the adaptation of bacteria to the gut microbiota.","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"2022 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2022-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47454125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Pattern of Microorganisms and Drug Susceptibility in Pediatric Oncologic Patients with Febrile Neutropenia.","authors":"Thanyathorn Jungrungrueng,&nbsp;Suvaporn Anugulruengkitt,&nbsp;Supanun Lauhasurayotin,&nbsp;Kanhatai Chiengthong,&nbsp;Hansamon Poparn,&nbsp;Darintr Sosothikul,&nbsp;Piti Techavichit","doi":"10.1155/2021/6692827","DOIUrl":"https://doi.org/10.1155/2021/6692827","url":null,"abstract":"<p><strong>Objective: </strong>The study aimed to describe the pattern of causative microorganisms, drug susceptibility, risk factors of antibiotic-resistant bacterial infection, and clinical impact of these organisms on pediatric oncology patients with febrile neutropenia.</p><p><strong>Methods: </strong>A retrospective descriptive study of oncologic patients aged less than 15 years who were diagnosed with febrile neutropenia in King Chulalongkorn Memorial Hospital was conducted between January 2013 to December 2017. Characteristics and clinical outcomes of febrile neutropenia episodes, causative pathogens, and their antibiotic susceptibilities were recorded.</p><p><strong>Result: </strong>This study included 267 patients with 563 febrile neutropenia episodes. The median (range) age was 5.1 years (1 month-15 years). The most common underlying disease was acute lymphoblastic leukemia (42.7%). Of 563 febrile episodes, there were 192 (34.1%) with microbiologically documented infection. Among these 192 episodes of microbiologically documented infection, there were 214 causative pathogens: 154 bacteria (72%), 32 viruses (15%), 27 fungus (12.6%), and 1 <i>Mycobacterium tuberculosis</i> (0.4%). Gram-negative bacteria (48.6%) accounted for most of the causative pathogens. Twenty-three percent of them were multidrug resistant, and 18% were carbapenem resistant. Among Gram-positive bacterial infection which accounted for 23.4% of all specimens, the proportion of MRSA was 20%. The 2-week mortality rate was 3.7%. Drug-resistant Gram-negative bacterial infection caused significant adverse events and mortality compared to nonresistant bacterial infection (<i>p</i> < 0.05).</p><p><strong>Conclusion: </strong>There is high rate of drug-resistant organism infection in pediatric oncology patients in a tertiary-care center in Thailand. Infection with drug-resistant Gram-negative bacterial infection was associated with significant morbidity and mortality. Continuous surveillance for the pattern of drug-resistant infections is crucial.</p>","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"2021 ","pages":"6692827"},"PeriodicalIF":2.6,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8021465/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25592036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resistance Status of Bacteria from a Health Facility in Ghana: A Retrospective Study.","authors":"Abass Inusah,&nbsp;Elvis Quansah,&nbsp;Kwabena Fosu,&nbsp;Isaac Dadzie","doi":"10.1155/2021/6648247","DOIUrl":"https://doi.org/10.1155/2021/6648247","url":null,"abstract":"<p><strong>Background: </strong>Regardless of the global concerted effort to control the development and spread of antimicrobial resistance, increasing cases are continually documented at many medical centres. This situation is reinforced by inadequate information on the trend of resistance resulting from lack of regular antimicrobial resistance surveillance. The present study sought to detect the number of multidrug-resistant (MDR), extended drug-resistant (XDR), and pandrug-resistant (PDR) bacterial isolates at a health facility in Ghana from January 2018 to July 2020.</p><p><strong>Method: </strong>A total of 800 data on antimicrobial testing results were extracted from the records of the health facility. The extracted data were explored for the detection of MDR, XDR, and PDR. The study further determined the use of antibiotics using the multiple-drug resistance index (MDRI).</p><p><strong>Results: </strong>Except for <i>Staphylococcus</i> and <i>Neisseria</i> spp., all bacterial isolates showed extremely high (100%) proportion of MDR. Although only <i>Staphylococcus</i> spp. (38 (4.8%)) was observed to be XDR, the rest of the bacteria showed the potential to attain the status of XDR or PDR. MDRI indicated high use of antibiotics in the health facility.</p><p><strong>Conclusion: </strong>The high antimicrobial resistance observed by the study underscores the need for prompt and effective antibiotic resistance control strategies.</p>","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"2021 ","pages":"6648247"},"PeriodicalIF":2.6,"publicationDate":"2021-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7952191/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25501177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Topical <i>Bambusa vulgaris</i> Extract Enhances Wound Healing in Cutaneous Leishmaniasis.","authors":"Zahra Ghanbarinasab,&nbsp;Mahnaz Hosseini-Bensenjan,&nbsp;Elaheh Ziaei Ziabari,&nbsp;Shiva Aminnia,&nbsp;Roham Borazjani,&nbsp;Mohammad Rastegarian Jahromi,&nbsp;Qasem Asgari,&nbsp;Bahador Sarkari,&nbsp;Soheil Ashkani-Esfahani","doi":"10.1155/2021/7860474","DOIUrl":"https://doi.org/10.1155/2021/7860474","url":null,"abstract":"<p><strong>Background: </strong><i>Bambusa vulgaris</i> (Tabashir) has been shown to have antimicrobial, antioxidant, and anti-inflammatory effects due to the presence of ascorbic acid, vitamin B2, flavonoid, and phenolic compounds which can be beneficial in the process of wound healing. The current study aimed to evaluate the effects of topical Tabashir extract on cutaneous leishmaniasis (CL) caused by <i>Leishmania major</i> in BALB/c mice.</p><p><strong>Methods: </strong>Twenty-eight female BALB/c mice (4 weeks old, 18 ± 4 grams) were injected subcutaneously in tail-base with <i>L. major</i> amastigotes. Treatment started when the CL lesions were appeared and continued for 21 days. Mice were then divided into four groups: <i>E</i>1, treated daily with 5% of Tabashir extract gel; <i>E</i>2, treated daily with 10% Tabashir gel; <i>C</i>1, irrigated daily only with normal saline; and <i>C</i>2, received vehicle gel daily. The wounds' sizes were measured every 3 days, using vernier caliper. The volume densities of vessels, collagens, and hair follicles, vessels' length density, and mean diameter were soteriologically determined.</p><p><strong>Results: </strong>Tabashir enhanced wound closure rate through increasing the number of fibroblasts, collagen bundles, and vessels, according to histomorphometric evaluation while it did not affect the parasitic load. Findings of the in vitro study revealed that the extract has substantial mortality for the <i>Leishmania</i> promastigotes.</p><p><strong>Conclusion: </strong>Topical Tabashir showed promising effects on the healing process of skin wounds caused by CL in this experimental study. Further studies are suggested to find out the molecules which are involved in the healing process.</p>","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"2021 ","pages":"7860474"},"PeriodicalIF":2.6,"publicationDate":"2021-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7892243/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25408454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimalarial Activity of <i>Nigella sativa</i> L. Seed Extracts and Selection of Resistance in <i>Plasmodium berghei</i> ANKA in a Mouse Model.","authors":"Rahma Udu,&nbsp;Job Oyweri,&nbsp;Jeremiah Gathirwa","doi":"10.1155/2021/6165950","DOIUrl":"https://doi.org/10.1155/2021/6165950","url":null,"abstract":"<p><strong>Background: </strong>Chemotherapy plays a crucial role in malaria control. However, the main obstacle to treatment has been the rise of parasite resistance to most antimalarial drugs. Artemisinin-based combination therapies (ACTs) remain the most effective antimalarial medicines available today. However, malaria parasite tolerance to ACTs is now increasingly prevalent especially in Southeast Asia presenting the danger of the spread of ACTs resistance to other parts of the world. Consequently, this creates the need for alternative effective antimalarials. Therefore, this study sought out to determine antimalarial potential, safety, and resistance development of the extracts in a mouse model.</p><p><strong>Method: </strong>Methanolic and ethyl acetate extracts were obtained by solvent extraction. The extracts were assayed for acute toxicity <i>in vivo</i>. Additionally, the two extracts were evaluated for antimalarial activity <i>in vivo</i> against <i>Plasmodium berghei</i> ANKA strain by the 4-day suppressive test at 500, 250, and 125 mg/kg/day. Packed cell volume was evaluated to determine anemia manifestation. Finally, continuous drug pressure experiment at 500 mg/kg and DNA amplification via PCR were conducted. The amplicons underwent through Sanger sequencing.</p><p><strong>Results: </strong>There was no toxicity realized in the animals at 2000 mg/kg. Importantly, high parasitemia suppression of 75.52% and 75.30% using a dose of 500 mg/kg of methanolic and ethyl acetate extracts, respectively, was noted. The extracts were able to reverse packed cell volume reduction. <i>Nigella sativa</i>-resistant phenotype was selected as delayed parasite clearance. However, there was no change in the nucleotide sequences of <i>Pb</i>MDR1 and <i>Pb</i>CRT genes.</p><p><strong>Conclusion: </strong>The results provide room for future exploitation of the plant as an antimalarial.</p>","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"2021 ","pages":"6165950"},"PeriodicalIF":2.6,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7875626/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25404672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SARS-CoV-2, Early Entry Events.","authors":"James P Chambers, Jieh Yu, James J Valdes, Bernard P Arulanandam","doi":"10.1155/2020/9238696","DOIUrl":"10.1155/2020/9238696","url":null,"abstract":"<p><p>Viruses are obligate intracellular parasites, and host cell entry is the first step in the viral life cycle. The SARS-CoV-2 (COVID-19) entry process into susceptible host tissue cells is complex requiring (1) attachment of the virus via the conserved spike (S) protein receptor-binding motif (RBM) to the host cell angiotensin-converting-enzyme 2 (ACE2) receptor, (2) S protein proteolytic processing, and (3) membrane fusion. Spike protein processing occurs at two cleavage sites, i.e., S₁/S₂ and S₂'. Cleavage at the S₁/S₂ and S₂' sites ultimately gives rise to generation of competent fusion elements important in the merging of the host cell and viral membranes. Following cleavage, shedding of the S₁ crown results in significant conformational changes and fusion peptide repositioning for target membrane insertion and fusion. Identification of specific protease involvement has been difficult due to the many cell types used and studied. However, it appears that S protein proteolytic cleavage is dependent on (1) furin and (2) serine protease transmembrane protease serine 2 proteases acting in tandem. Although at present not clear, increased SARS-CoV-2 S receptor-binding motif binding affinity and replication efficiency may in part account for observed differences in infectivity. Cleavage of the ACE2 receptor appears to be yet another layer of complexity in addition to forfeiture and/or alteration of ACE2 function which plays an important role in cardiovascular and immune function.</p>","PeriodicalId":16788,"journal":{"name":"Journal of Pathogens","volume":"2020 ","pages":"9238696"},"PeriodicalIF":2.6,"publicationDate":"2020-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7707962/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38355937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}