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Objective: We assessed the effectiveness of oral Hydroxychloroquine (HC), Azithromycin (AZ) and Oseltamivir (OS), alone or combined, among patients hospitalized with mildly symptomatic coronavirus infectious disease (COVID-19). Methods: Following the approval of the National Bioethics Committee and prospective registration (clinicaltrials.gov NCT04338698), a multicenter randomized clinical trial of adaptive design was conducted at 10 multispecialty hospitals in Pakistan. Patients were randomized into seven treatment groups. Starting April 15, 2020, consenting, eligible, otherwise healthy adult patients or those with co-morbidities under control, were recruited if they presented with mildly symptomatic COVID-19 (scored 3 on a 7-point ordinal scale anchored between 1 = not hospitalized, able to undertake normal activities, to 7 = death) confirmed by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). Two primary outcomes were assessed by day seven: Turning qRT-PCR negative; and clinical improvement of two points from the baseline. Outcome rates were compared using a chi-square test. Multiple imputations were applied to handle missing data. An interim data analysis was carried out on July 19, 2020, following which the study continued without treatment group changes. Data Safety and Monitoring Board advised to stop recruitment due to its futility on January 18, 2021. Results: Of 471 patients randomized, a total of 426 (90.4%) completed the follow-up for primary outcomes. Based on imputed data analyses at day seven: Total qRT-PCR negative cases were 137/471 (29%, 95% CI 25.0 - 33.4). By day seven, a total of 111/471 (23.5%, 95% CI 19.8 - 27.6) showed clinical improvement. No serious or non-serious adverse event was reported. Conclusions: Among patients with mild COVID-19, there was no statistically significant difference in the effectiveness of oral antimalarial, antiviral, or antibiotic treatments.Clinicaltrials.gov ID: NCT04338698.
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Glabridin, a polyphenolic flavonoid derived from Glycyrrhiza glabra (licorice) roots, has shown anti-inflammatory and antioxidant properties. The current study sought to investigate glabridin's immunomodulatory effect in ovalbumin induced allergic asthma. Healthy male Wistar rats were divided into five groups. Group I served as a control group. Asthma was induced in groups II- IV. Groups III and IV were treated with glabridin (40 mg/kg) and methylprednisolone (15 mg/kg), respectively. Inflammatory cells counts were determined in blood and bronchoalveolar lavage fluid (BALF). Serum IgE levels and levels of catalase, superoxide dismutase and glutathione peroxidase in lung homogenate were measured. The levels of mRNA expression of pro-inflammatory, anti-inflammatory and oxidative stress markers were analysed. Delayed type hypersensitivity (DTH) and acute toxicity of glabridin were also checked. Glabridin significantly decreased inflammatory cells in the blood and BALF. It increased the concentration of antioxidant enzymes catalase, superoxide dismutase and glutathione peroxidase. Glabridin markedly decreased serum IgE levels and DTH when compared to asthmatic rats. It significantly alleviated the expression of TNF-α, IL-4, IL-5, CXCL1, iNOS, and NF-κB. Administering 10 times the therapeutic dose of glabridin did not show any signs of acute toxicity. Findings suggest that glabridin has the potential to ameliorate allergic asthma and its effects are comparable to those of methylprednisolone. The immunomodulatory effect of glabridin might be contributed by the suppression of pro-inflammatory cytokines, oxidative stress markers, IgE antibodies, and elevation of antioxidant enzymes, suggesting future study and clinical trials to propose it as a candidate to treat allergic asthma.
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The chemotherapeutic agent known as 5-fluorouracil (5-FU) is an artificial fluoropyrimidine antimetabolite that has been widely used for its antineoplastic properties. Cocrystals of 5-fluorouracil (5-FU) with five different Schiff bases (benzylidene-urea (BU), benzylidene-aniline (BA), salicylidene-aniline (SA), salicylidene-phenylhydrazine (SPH), and para-hydroxy benzylideneaniline (HBA)) are reported in this study. The newly synthesized cocrystals were analyzed by FTIR and PXRD. In this study, we investigated the antitumor efficacy of 5-FU derivatives in SW480 colon cancer cells via MTT assay at varying dose concentrations. Molecular docking was performed to predict the binding mechanism of TS with various 5-FU complexes. FTIR revealed the presence of respective functional groups in the prepared cocrystals. The frequencies (v) of N-H (3220.24 cm-1) and carbonyl groups (1662.38 cm-1) in the spectrum of 5-FU shifted considerably in all derivative cocrystal new interactions. There was a noticeable transformation in the PXRD peak of 5-FU at 2θ = 28.37° in all derivatives. The novelty of the present study lies in the fact that 5-FU-BA showed an anticancer potential IC50 (6.4731) far higher than that of 5-FU (12.116), almost comparable to that of the reference drug doxorubicin (3.3159), against SW480 cancel cell lines, followed by 5-Fu-HBA (10.2174). The inhibition rates of 5-FU-BA and 5-FU-HBA were highest among the derivatives (99.85% and 99.37%, respectively) in comparison with doxorubicin (97.103%). The results revealed that the synthesized 5-FU cocrystals have promising antitumor efficacy compared with previously reported 5-FU and 5-FU. The activities of the cocrystals were rationalized by a molecular modeling approach to envisage binding modes with the target cancer protein.
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Chrysin (5,7-dihydroxyflavone) has many pharmacological properties including anti-inflammatory actions. The objective of this study was to evaluate the anti-arthritic activity of chrysin and to compare its effect with the non-steroidal anti-inflammatory agent, piroxicam, against complete Freund's adjuvant (CFA)-induced arthritis in a pre-clinical model in rats. Rheumatoid arthritis was induced by injecting CFA intra-dermally in the sub-plantar region of the left hind paw of rats. Chrysin (50 and 100 mg/kg) and piroxicam (10 mg/kg) were given to rats with established arthritis. The model of arthritis was characterized using an index of arthritis, with hematological, biological, molecular, and histopathological parameters. Treatment with chrysin significantly reduced the arthritis score, inflammatory cells, erythrocyte sedimentation rate, and rheumatoid factor. Chrysin also reduced the mRNA levels of tumor necrosis factor, nuclear factor kappa-B, and toll-like recepter-2 and increased anti-inflammatory cytokines interleukin-4 and -10, as well as the hemoglobin levels. Using histopathology and microscopy, chrysin reduced the severity of arthritis in joints, infiltration of inflammatory cells, subcutaneous inflammation, cartilage erosion, bone erosion, and pannus formation. Chrysin showed comparable effects to piroxicam, which is used for the treatment of rheumatoid arthritis. The results showed that chrysin possesses anti-inflammatory and immunomodulatory effects that make it a potential drug for the treatment of arthritis.
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Rheumatoid arthritis is a chronic systemic inflammatory disease with genetic manifestations. According to recently published case reports, patients taking corticosteroid medication for the management of rheumatoid arthritis develop strongloidiasis and are at high risk of developing associated infections. This study explored the antiarthritic role of ivermectin, a drug used in the treatment of strongyloides and to compare its results with dexamethasone. Thirty-two male Wistar rats were randomly divided into four groups: control, diseased, dexamethasone, and ivermectin groups. Rheumatoid arthritis in all rats except the control group was induced by using complete Freund's adjuvant. After 7 days of rheumatoid arthritis induction, animals were treated with dexamethasone 5 mg/kg and ivermectin 6 mg/kg. Body weight, visual arthritic score, total leukocyte count, differential leukocyte count, proinflammatory genes, and histopathological findings were used to assess the effects of ivermectin on rheumatoid arthritis. Treatment with ivermectin showed a significant reduction in inflammatory cells levels, body weight, and visual arthritic score, indicating an improvement in the degree of inflammation as compared with the diseased group. Treatment with ivermectin and dexamethasone significantly reduced the augmentation in the mRNA expression levels of IL-17, TLR-2, TNF, and NF-κB as a result of arthritic development. Ivermectin treatment also showed a significant reduction in the severity of inflammation and destruction of joints and showed comparable effects to dexamethasone, a corticosteroid used for the treatment of rheumatoid arthritis. Ivermectin has significant antiarthritic properties and can be a novel treatment agent for the management of rheumatoid arthritis patients suffering from strongyloidiasis.
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Artrite Experimental , Artrite Reumatoide , Ratos , Masculino , Animais , Ratos Wistar , Adjuvante de Freund/efeitos adversos , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Extratos Vegetais/farmacologia , Mediadores da Inflamação , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Artrite Experimental/induzido quimicamente , Artrite Experimental/tratamento farmacológico , Inflamação/tratamento farmacológico , Inflamação/induzido quimicamente , Artrite Reumatoide/tratamento farmacológico , Peso Corporal , Dexametasona/farmacologia , Dexametasona/uso terapêuticoRESUMO
Diabetic nephropathy is the leading cause of end-stage renal failure, but the effectiveness of currently available strategies for preventing diabetic nephropathy remains unsatisfactory. This study was designed to evaluate the changes in adipokines levels caused by dipeptidyl peptidase-4 inhibitor sitagliptin therapy as one of the possible mechanisms of sitagliptin's amelioration of diabetic nephropathy. Twenty-four male Wistar rats weighing 180-200 g were taken and divided into three groups, that is, control, diseased, and treatment group. High-fat diet and streptozotocin-induced Type 2 diabetic rats were divided into diseased and treatment groups. The treatment group was given sitagliptin orally, 10 mg/kg per day for 6 weeks. Serum glucose, serum insulin, serum blood urea nitrogen, serum creatinine, and 24-h urinary protein levels were measured in serum and urine samples. mRNA expression levels of podocin, nephrin, and adipokines in renal tissues were determined. Results showed that sitagliptin treatment effectively reduced serum glucose, serum creatinine, serum blood urea nitrogen, and 24-h proteinuria, along with partial prevention of insulinopenia, in the treatment group as compared to the diseased group. The renal mRNA expression levels of podocin, nephrin, and adiponectin were significantly upregulated, while those of leptin and resistin were significantly downregulated in the diabetic rats receiving sitagliptin therapy compared to the non-treated diabetic rats. Based on these findings, it is suggested that sitagliptin, via mediating the modulation of adipokines levels, upregulates renal nephrin and podocin expression, which leads to the amelioration of diabetic nephropathy.
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Diabetes Mellitus Experimental , Nefropatias Diabéticas , Ratos , Masculino , Animais , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Fosfato de Sitagliptina/farmacologia , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Adipocinas , Creatinina , Ratos Wistar , Glucose , RNA MensageiroRESUMO
Nimbolide is an active constituent of Azadirachta indica and is known for its anti-inflammatory, anti-oxidant, immune-modulatory, and anti-cancer effects. Few studies suggest that nimbolide treatment influences the responses to rheumatoid arthritis, but the underlying molecular mechanisms involved are not yet well established. Therefore, the present study was designed to determine the effect of nimbolide on expression regulation of toll-like receptors to attenuate rheumatoid arthritis. The rheumatoid arthritis model was established by injecting complete Freund's adjuvant (CFA) intra-dermally into the sub-plantar region of the left hind paw of rats. Nimbolide (20 mg/kg) and piroxicam (10 mg/kg) were given to arthritic rats. Rats treated with nimbolide showed a significant reduction in inflammatory cells, rheumatoid factor, ESR, and improved the body weight. The results indicated that nimbolide possesses the capacity to attenuate rheumatoid arthritis by downregulating toll-like receptors, IL-17, IL-23, HSP70, and IFN-γ expression levels. Nimbolide treatment showed significant reduction in the severity of inflammation and destruction of joints and showed comparable effects to piroxicam, which is a standard non-steroidal anti-inflammatory drug used for the treatment of rheumatoid arthritis. It can be concluded that nimbolide can be considered as a potential candidate for therapeutic targeting of the toll-like receptors pathway in rheumatoid arthritis.
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Artrite Experimental , Artrite Reumatoide , Ratos , Animais , Adjuvante de Freund/efeitos adversos , Piroxicam/efeitos adversos , Artrite Experimental/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Transdução de Sinais , Artrite Reumatoide/tratamento farmacológico , Antioxidantes/uso terapêuticoRESUMO
BACKGROUND AND OBJECTIVE: Psoriasis is a chronic skin disease with 2-4% of prevalence worldwide conferring a major burden on health systems. It is assumed that the prevalence might increase due to climatic change and deterioration of protective ozone barrier. With the chances of increasing prevalence, newer and specific treatment options need to be explored. Skin is a constant target of oxidative stress owing to continuous exposure to ultraviolet radiations. Oxidative stress is considered to have a central role in dermatological diseases, including psoriasis. This study was designed to explore the role of Humanin analogue (S14-G HNG) as an important anti oxidant for psoriasis like condition in BALB/c mice as till date the commomly used drugs for this disease are corticosteroids which have a dissatisfactory adverse effect profile in terms of chronic use. METHODOLOGY: Imiquimod 5% was used to induce Psoriasis like condition in mice, and the role of HNG was assessed through the histological examination, protein expressions and markers of oxidative stress. Two doses (low and high) of HNG were used and results were compared with an established drug methylprednisolone. KEY RESULT: Significant improvement was seen on histology, PASI scoring, protein expression and oxidative stress by the use of intraperitoneal injections of S14-G HNG and the results were comparable to those obtained through peritoneal injections of methylprednisolone. CONCLUSION: S14G-HNG can be considered as a suitable option for treatment of Psoriasis after clinical trials and it might prove to have lesser side effects as compared to other drugs employed for the treatment of psoriasis being an innate anti oxidant and anti apoptotic compound.
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Antioxidantes , Psoríase , Animais , Antioxidantes/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular , Metilprednisolona/uso terapêutico , Camundongos , Psoríase/tratamento farmacológicoRESUMO
Antimicrobial resistance is an alarming problem, especially due to emergence of methicillin-resistance Staphylococcus aureus (MRSA). World Health Organization (WHO) has already listed MRSA as a top priority pathogen for the development of novel antibacterial agents. Presently, different therapeutic approaches against bacterial infections are in practice which includes targeting bacterial virulence factors, bacteriophage therapy, and manipulation of the microbiome. Natural products have been efficiently used for centuries to combat bacterial infections. Morchella is a natural fungal product which has been reported to possess broad-spectrum biological activities against bacterial infections. Hence, this study was aimed to evaluate the antibacterial efficacy of two macro-fungi against S. aureus, MRSA, and Streptococcus pyogenes (S. pyogenes). The antibacterial potential of both fungal extracts (Morchella esculenta and Morchella conica) was evaluated using disk diffusion and standard broth microdilution methods. The chemical compounds of both fungi were investigated using ultra-performance liquid chromatography mass spectroscopy (UPLC-MS) analysis. All fungal extracts inhibited growth of tested bacteria with inhibitory zone ranging from 10.66 ± 0.3 to 21.00 ± 1.5 mm. The minimum inhibitory concentration (MIC) of tested bacterial growth ranged from 03.33 to 16.0 mg/ml. It was noteworthy that Morchella extracts prevented S. aureus growth in a bactericidal manner with minimal bactericidal concentration (MBC) of 8-16 mg/ml. The extracts were also more effective against MRSA than currently available antibiotics. In conclusion, the growth inhibition of tested bacteria by fungal extracts revealed their potential as antibacterial agents and their compounds may be used as drug candidates.
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Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Ascomicetos , Cromatografia Líquida , Meticilina/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Staphylococcus aureus , Streptococcus pyogenes , Espectrometria de Massas em TandemRESUMO
Coronavirus disease 2019 (COVID-19) is a novel respiratory disease that has led to a global pandemic and created a havoc. The COVID-19 disease severity varies among individuals, depending on fluctuating symptoms. Many infectious diseases such as hepatitis B and dengue hemorrhagic fever have been associated with ABO blood groups. The aim of this study was to explore whether ABO blood groups might serve as a risk or a protective factor for COVID-19 infection. Moreover, the symptomatic variations of COVID-19 infection among the individuals with different blood groups were also analyzed. An online questionnaire-based survey was conducted in which 305 partakers were included, who had successfully recovered from coronavirus infection. The ABO blood groups of 1294 healthy individuals were also taken as a control. The results of the current study demonstrated that antibody A containing blood groups (blood group B, p-value: 0.049 and blood group O, p-value: 0.289) had a protective role against COVID-19 infection. The comparison of symptomatic variations among COVID-19-infected subjects showed that blood group O subjects had lower chances of experiencing severe symptoms relating to respiratory distress, while subjects with AB blood group were more prone to develop symptoms, but the differences in both groups were found to be statistically non-significant. In conclusion, subjects who do not have anti-A antibodies in their serum (i.e., subjects with group A and AB) are more likely to be infected with COVID-19. The current data showed that there was no significant association of signs and symptoms variations of COVID-19 infection among individuals with different blood groups.
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Sistema ABO de Grupos Sanguíneos , COVID-19/sangue , Adolescente , Adulto , Distribuição por Idade , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos de Casos e Controles , Suscetibilidade a Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Distribuição por Sexo , Inquéritos e Questionários , Adulto JovemRESUMO
While the world has experience with many different types of infectious diseases, the current crisis related to the spread of COVID-19 has challenged epidemiologists and public health experts alike, leading to a rapid search for, and development of, new and innovative solutions to combat its spread. The transmission of this virus has infected more than 18.92 million people as of August 6, 2020, with over half a million deaths across the globe; the World Health Organization (WHO) has declared this a global pandemic. A multidisciplinary approach needs to be followed for diagnosis, treatment and tracking, especially between medical and computer sciences, so, a common ground is available to facilitate the research work at a faster pace. With this in mind, this survey paper aimed to explore and understand how and which different technological tools and techniques have been used within the context of COVID-19. The primary contribution of this paper is in its collation of the current state-of-the-art technological approaches applied to the context of COVID-19, and doing this in a holistic way, covering multiple disciplines and different perspectives. The analysis is widened by investigating Artificial Intelligence (AI) approaches for the diagnosis, anticipate infection and mortality rate by tracing contacts and targeted drug designing. Moreover, the impact of different kinds of medical data used in diagnosis, prognosis and pandemic analysis is also provided. This review paper covers both medical and technological perspectives to facilitate the virologists, AI researchers and policymakers while in combating the COVID-19 outbreak.
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BACKGROUND: Actinobacteria are famous for the production of unique secondary metabolites that help in controlling the continuously emerging drug resistance all over the globe. This study aimed at the investigation of an extreme environment the Cholistan desert, located in southern Punjab, Pakistan, for actinobacterial diversity and their activity against methicillin resistant Staphylococcus aureus (MRSA). The Cholistan desert is a sub-tropical and arid ecosystem with harsh environment, limited rainfall and low humidity. The 20 soil and sand samples were collected from different locations in the desert and the actinobacterial strains were selectively isolated. The isolated strains were identified using a polyphasic taxonomic approach including morphological, biochemical, physiological characterization, scanning electron microscopy (SEM) and by 16S rRNA gene sequencing. RESULTS: A total of 110 desert actinobacterial strains were recovered, which were found to be belonging to 3 different families of the order Actinomycetales, including the family Streptomycetaceae, family Pseudonocardiaceae and the family Micrococcaceae. The most frequently isolated genus was Streptomyces along with the genera Pseudonocardia and Arthrobacter. The isolated strains exhibited promising antimicrobial activity against methicillin resistant Staphylococcus aureus (MRSA) with zone of inhibition in the range of 9-32 mm in antimicrobial screening assays. The chemical profiling by thin layer chromatography, HPLC-UV/Vis and LC-MS analysis depicted the presence of different structural classes of antibiotics. CONCLUSION: The study revealed that Cholistan desert harbors immense actinobacterial diversity and most of the strains produce structurally diverse bioactive secondary metabolites, which are a promising source of novel antimicrobial drug candidates.
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Actinobacteria/química , Actinobacteria/classificação , Antibacterianos/farmacologia , Actinobacteria/fisiologia , Antibacterianos/isolamento & purificação , DNA Bacteriano/genética , Clima Desértico , Ecossistema , Variação Genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Paquistão , Filogenia , Análise de Sequência de DNA , Microbiologia do Solo , Esporos Bacterianos/classificaçãoRESUMO
BACKGROUND: Actinomycetes are gram positive bacteria with high G + C content in their DNA and are capable of producing variety of secondary metabolites. Many of these metabolites possess different biological activities and have the potential to be developed as therapeutic agents. The aim of the present study was to screen actinomycetes inhabiting halophilic environment such as Khewra salt mines present in Pakistan for cytotoxic and antitumor compounds. RESULTS: An actiomycetes strain designated as Streptomyces sp. KML-2 was isolated from a saline soil of Khewra salt mines, Pakistan. The strain Streptomyces sp. KML-2 showed 84 % cytotoxic activity against larvae of Artemia salina. In the screening phase, the strain exhibited significant antitumor activity with IC50 values of 12, 48 and 56 µg/ml against Hela, MDBK and Vero cell lines, respectively. After that extract from 20 l fermentation was used to purify secondary metabolites by several chromatographic techniques. Structure elucidation of isolated compounds revealed that it is highly stable producer of Chromomycin SA (1) and 1-(1H-indol-3-yl)-propane-1,2,3-triol (2). Both of the isolated compounds showed significant antitumor activity against Hela and MCF-7 cancer cell lines (IC50 values 8.9 and 7.8 µg/ml against Hela; 12.6 and 0.97 µg/ml against MCF-7, respectively). The 16S rRNA gene sequence (1437 bp) of the strain confirm its identity (99 %) with Streptomyces griseus. CONCLUSIONS: From this research work we were successful in isolating two potent antitumor compounds, Chromomycin SA and 1-(1H-indol-3-yl)-propane-1,2,3-triol from Streptomyces KML-2 strain, isolated from Khewra salt mine. As such this is the second report which confirms that S. griseus can produce Chromomycin SA without introducing any mutagenesis in its biosynthesizing gene cluster and isolated indole derivative is being reported first time from any member of actinomycetes group with having novel antitumor activity against Hela and MCF-7 cells. Nucleotide sequences: Nucleotide sequence data reported are available in the GenBank database under the accession number: GenBank KJ009562.
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Antineoplásicos/farmacologia , Microbiologia do Solo , Streptomyces/química , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antineoplásicos/isolamento & purificação , Artemia/classificação , Artemia/efeitos dos fármacos , Bovinos , Linhagem Celular , Chlorocebus aethiops , Cromatografia/métodos , Cromomicinas/classificação , Cromomicinas/farmacologia , Formazans , Glicerol/análogos & derivados , Glicerol/farmacologia , Células HeLa , Humanos , Concentração Inibidora 50 , Larva/efeitos dos fármacos , Células MCF-7 , Microscopia Eletrônica de Varredura , Mineração , Paquistão , Filogenia , RNA Ribossômico 16S/genética , Sais , Análise de Sequência de RNA , Solo/química , Streptomyces/isolamento & purificação , Streptomyces/ultraestrutura , Streptomyces griseus/classificação , Sais de Tetrazólio , Células VeroRESUMO
Actinomycetes are well known group of gram positive bacteria for their potential to produce antibiotics. This study sought to assess the ability of the selected actinomycetes to control biofilm forming bacteria isolated from different dental plaque samples. On the basis of morphological differences three out of ten different dental plaque bacterial isolates were selected for further study. These isolates were biochemically and genetically characterized and were identified as Acinetobacter schinndleri, Moraxella aci, and Bacillus cereus. Antibiotic resistant profile was measured through disc diffusion method and found that all three isolates were moderately sensitive to ofloxacin and erythromycin and resistant to trimethoprim. Antibacterial activity of ten different Streptomyces strains was assessed through an agar plug and well diffusion method against three dental biofilm forming bacteria. Two Streptomyces strains named as S. erythrogriseus and S. labedae showed good antibacterial activity against Moraxella and Acinetobacter strains. Ability of the four active antibiotic producing strains to inhibit biofilm formation was assessed using microtiter biofilm detection assay. It was found that biofilm forming ability of Acinetobacter and Moraxella was inhibited by S. labedae an antibiotic producing strain, while S. macrosporeus can only inhibit biofilm formation by B. cereus.
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Acinetobacter/efeitos dos fármacos , Antibacterianos/farmacologia , Bacillus/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Moraxella/efeitos dos fármacos , Streptomyces/química , Acinetobacter/classificação , Acinetobacter/isolamento & purificação , Acinetobacter/fisiologia , Antibacterianos/isolamento & purificação , Bacillus/classificação , Bacillus/isolamento & purificação , Bacillus/fisiologia , Biofilmes/crescimento & desenvolvimento , Misturas Complexas/isolamento & purificação , Misturas Complexas/farmacologia , Placa Dentária/microbiologia , Testes de Sensibilidade Microbiana , Moraxella/classificação , Moraxella/isolamento & purificação , Moraxella/fisiologiaRESUMO
BACKGROUND: Actinomycetes are gram positive bacteria with high G + C content in their DNA and are capable of producing variety of secondary metabolites. Many of these metabolites possess different biological activities and have the potential to be developed as therapeutic agents. The aim of the present study was to screen actinomycetes inhabiting halophilic environment such as Khewra salt mines present in Pakistan for cytotoxic and antitumor compounds. RESULTS: An actiomycetes strain designated as Streptomyces sp. KML-2 was isolated from a saline soil of Khewra salt mines, Pakistan. The strain Streptomyces sp. KML-2 showed 84 % cytotoxic activity against larvae of Artemiasalina. In the screening phase, the strain exhibited significant antitumor activity with IC50 values of 12, 48 and 56 µg/ml against Hela, MDBK and Vero cell lines, respectively. After that extract from 20 l fermentation was used to purify secondary metabolites by several chromatographic techniques. Structure elucidation of isolated compounds revealed that it is highly stable producer of Chromomycin SA (1) and 1-(1H-indol-3-yl)-propane-1,2,3-triol (2). Both of the isolated compounds showed significant antitumor activity against Hela and MCF-7 cancer cell lines (IC50 values 8.9 and 7.8 µg/ml against Hela; 12.6 and 0.97 µg/ml against MCF-7, respectively). The 16S rRNA gene sequence (1437 bp) of the strain confirm its identity (99 %) with Streptomyces griseus. CONCLUSIONS: From this research work we were successful in isolating two potent antitumor compounds, Chromomycin SA and 1-(1H-indol-3-yl)-propane-1,2,3-triol from Streptomyces KML-2 strain, isolated from Khewra salt mine. As such this is the second report which confirms that S. griseus can produce Chromomycin SA without introducing any mutagenesis in its biosynthesizing gene cluster and isolated indole derivative is being reported first time from any member of actinomycetes group with having novel antitumor activity against Hela and MCF-7 cells Nucleotide sequences: Nucleotide sequence data reported are available in the GenBank database under the accession number: GenBank KJ009562.