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1.
J Fluoresc ; 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37672182

RESUMO

Current study was aimed to determine the antibacterial, antioxidant and cytotoxic potential of Titanium dioxide nanoparticles (TiO2NPs) and Zinc oxide nanoparticles (ZnONPs). Nanoparticles were characterized by UV-Vis spectrophotometry, particle size analyzer (PSA), fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The Minimum inhibitory concentration (MIC) was determined by standard agar dilution method. Antibacterial potential of nanoparticles was analyzed by standard disc diffusion method against bacterial strains including Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumonia. Different concentrations of NPs (0.2, 0.4, 0.6, 0.8, 1.0, 1.2 and 1.4 mg/mL) were incorporated to evaluate the antimicrobial activity. Antioxidant activity and cytotoxicity of these NPs was analyzed by DPPH method and brine shrimp cytotoxicity assay, respectively. The MIC of TiO2NPs against E. coli, P. aeruginosa and K. pneumoniae was 0.04, 0.08 and 0.07 mg/mL respectively while the MIC of ZnONPs against the above strains was 0.01, 0.015 and 0.01 mg/mL. The maximum zone of inhibition was observed for K. pneumoniae i.e., 20mm and 25mm against TiO2 and ZnO NPs respectively, at 1.4 mg/mL concentration of NPs. The susceptibility of NPs against bacterial strains was evaluated in the following order: K. pneumoniae > P. aeruginosa > E. coli. The antioxidant activity of nanoparticles increased by increasing the concentration of NPs while cytotoxic analysis exhibited non-toxic effect of ZnO NPs while TiO2 had toxic effects on 1.2 and 1.4 mg/mL concentrations. Results revealed that ZnO NPs have more antibacterial and negligible cytotoxic potential in contrast to TiO2 NPs.

2.
J Pak Med Assoc ; 66(7): 819-22, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27427129

RESUMO

OBJECTIVE: To check the incidence of environmental and genetic factors causing congenital cataract in infants. METHODS: The descriptive study was conducted at Layton Rahmatullah Benevolent Trust, Lahore, Pakistan, from October 2013 to April 2014, and comprised children under 15 years of age who had rubella syndrome, herpes simplex, birth trauma, trisomy 21, Nance-Horan syndrome or Lowe's syndrome. RESULTS: Of the 38,000 cases examined, 120(0.3%) patients were diagnosed with congenital cataract. Of them, 52(43.33%)were aged between 2 and 5 years,22(18.33%) <11 years and 10(8.33%) ?15 years. Bilateral congenital cataract was observed in 91(75.83%) patients and unilateral congenital cataract in 29(24.17%). Environmental factors caused 72(62.07%) cases and genetic factors caused 44(37.93%).. CONCLUSIONS: Congenital cataract predominated in boys compared to girls. Early diagnosis and adequate therapy requires specific technology, as well as long-term and permanent care..


Assuntos
Anormalidades Congênitas/epidemiologia , Adolescente , Catarata/congênito , Catarata/diagnóstico , Catarata/epidemiologia , Causalidade , Criança , Pré-Escolar , Técnicas de Diagnóstico Oftalmológico , Meio Ambiente , Feminino , Humanos , Incidência , Lactente , Masculino , Avaliação das Necessidades , Paquistão/epidemiologia
3.
Biol Trace Elem Res ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985237

RESUMO

Nanotechnology has become a major topic of study, particularly in the medical and health domains. Because nanomedicine has a higher recovery rate than other conventional drugs, it has attracted more attention. Green synthesis is the most efficient and sustainable method of creating nanoparticles. The current work used ultraviolet-visible spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray, and X-ray diffraction to thoroughly characterize the synthesized silver nanoparticles (AgNPs) from Azadirachta indica leaf extract. Characterization confirmed the synthesis of the AgNPs along with the possible linkage of the phytochemicals with the silver as well as the quantitative analysis and nature of NPs. The antioxidant activity of AgNPs and neem extract was measured by the 2,2-diphenyl-1-picrylhydrazyl assay using various concentrations (20, 40, 60, 80, and 100 µg/ml). Additionally, using diabetic mice that had been given alloxan, the in vivo antidiabetic potential of biosynthesized AgNPs was assessed. Eight groups of mice were used to assess the antidiabetic activity: one control group and seven experimental groups (untreated, extract-treated, AgNPs at low and high doses, standard drug, low dose of AgNPs + drug, and high dose of AgNPs + drug). At days 0, 7, 14, 21, and 28, blood glucose levels and body weight were measured. After 28 days, the mice were dissected, and the liver, kidney, and pancreas were examined histologically. The results depicted that the AgNPs showed higher (significant) radical scavenging activity (IC50 = 35.2 µg/ml) than extract (IC50 = 93.0 µg/ml) and ascorbic acid (IC50 = 64.6 µg/ml). The outcomes demonstrated that biosynthesized AgNPs had a great deal of promise as an antidiabetic agent and exhibited remarkable effects in diabetic mice given AgNPs, extract, and drug. Remarkable improvement in the body weight and blood glucose level of mice treated with high doses of AgNPs and drug was observed. The body weight and blood glucose level of diabetic mice treated with a high dose of AgNPs + standard drug showed significant improvement, going from 28.7 ± 0.2 to 35.6 ± 0.3 g and 248 ± 0.3 to 109 ± 0.1 mg/dl, respectively. Significant regeneration was also observed in the histomorphology of the kidney, liver's central vein, and islets of Langerhans after treatment with biosynthesized AgNPs. Diabetic mice given a high dose of AgNPs and drug displayed architecture of the kidney, liver, and pancreas that was nearly identical to that of the control group. According to the current research, biosynthesized AgNPs have strong antioxidant and antidiabetic potential and may eventually provide a less expensive option for the treatment of diabetes.

4.
Microorganisms ; 11(6)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37374866

RESUMO

Nanotechnology is a rapidly developing field of research that studies materials having dimensions of less than 100 nanometers. It is applicable in many areas of life sciences and medicine including skin care and personal hygiene, as these materials are the essential components of various cosmetics and sunscreens. The aim of the present study was to synthesize Zinc oxide (ZnO) and Titanium dioxide (TiO2) nanoparticles (NPs) by using Calotropis procera (C. procera) leaf extract. Green synthesized NPs were characterized by UV spectroscopy, Fourier transform infrared (FTIR), X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM) to investigate their structure, size, and physical properties. The antibacterial and synergistic effects of ZnO and TiO2 NPs along with antibiotics were also observed against bacterial isolates. The antioxidant activity of synthesized NPs was analyzed by their α-diphenyl-ß-picrylhydrazyl (DPPH) radical scavenging activity. In vivo toxic effects of the synthesized NPs were evaluated in albino mice at different doses (100, 200, and 300 mg/kg body weight) of ZnO and TiO2 NPs administered orally for 7, 14, and 21 days. The antibacterial results showed that the zone of inhibition (ZOI) was increased in a concentration-dependent manner. Among the bacterial strains, Staphylococcus aureus showed the highest ZOI, i.e., 17 and 14 mm against ZnO and TiO2 NPs, respectively, while Escherichia coli showed the lowest ZOI, i.e., 12 and 10 mm, respectively. Therefore, ZnO NPs are potent antibacterial agents compared to TiO2 NPs. Both NPs showed synergistic effects with antibiotics (ciprofloxacin and imipenem). Moreover, the DPPH activity showed that ZnO and TiO2 NPs have significantly (p > 0.05) higher antioxidant activity, i.e., 53% and 58.7%, respectively, which indicated that TiO2 has good antioxidant potential compared to ZnO NPs. However, the histological changes after exposure to different doses of ZnO and TiO2 NPs showed toxicity-related changes in the structure of the kidney compared to the control group. The current study provided valuable information about the antibacterial, antioxidant, and toxicity impacts of green synthesized ZnO and TiO2 NPs, which can be influential in the further study of their eco-toxicological effects.

5.
Microorganisms ; 11(9)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37764007

RESUMO

Overuse of pesticides in agricultural soil and dye-polluted effluents severely contaminates the environment and is toxic to animals and humans making their removal from the environment essential. The present study aimed to assess the biodegradation of pesticides (cypermethrin (CYP) and imidacloprid (IMI)), and dyes (malachite green (MG) and Congo red (CR)) using biofilms of bacteria isolated from pesticide-contaminated soil and dye effluents. Biofilms of indigenous bacteria, i.e., Bacillus thuringiensis 2A (OP554568), Enterobacter hormaechei 4A (OP723332), Bacillus sp. 5A (OP586601), and Bacillus cereus 6B (OP586602) individually and in mixed culture were tested against CYP and IMI. Biofilms of indigenous bacteria i.e., Lysinibacillus sphaericus AF1 (OP589134), Bacillus sp. CF3 (OP589135) and Bacillus sp. DF4 (OP589136) individually and in mixed culture were tested for their ability to degrade dyes. The biofilm of a mixed culture of B. thuringiensis + Bacillus sp. (P7) showed 46.2% degradation of CYP compared to the biofilm of a mixed culture of B. thuringiensis + E. hormaechei + Bacillus sp. + B. cereus (P11), which showed significantly high degradation (70.0%) of IMI. Regarding dye biodegradation, a mixed culture biofilm of Bacillus sp. + Bacillus sp. (D6) showed 86.76% degradation of MG, which was significantly high compared to a mixed culture biofilm of L. sphaericus + Bacillus sp. (D4) that degraded only 30.78% of CR. UV-VIS spectroscopy revealed major peaks at 224 nm, 263 nm, 581 nm and 436 nm for CYP, IMI, MG and CR, respectively, which completely disappeared after treatment with bacterial biofilms. Fourier transform infrared (FTIR) analysis showed the appearance of new peaks in degraded metabolites and disappearance of a peak in the control spectrum after biofilm treatment. Thin layer chromatography (TLC) analysis also confirmed the degradation of CYP, IMI, MG and CR into several metabolites compared to the control. The present study demonstrates the biodegradation potential of biofilm-forming bacteria isolated from pesticide-polluted soil and dye effluents against pesticides and dyes. This is the first report demonstrating biofilm-mediated bio-degradation of CYP, IMI, MG and CR utilizing soil and effluent bacterial flora from Multan and Sheikhupura, Punjab, Pakistan.

6.
Comb Chem High Throughput Screen ; 25(7): 1200-1206, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33653240

RESUMO

INTRODUCTION: Bacterial resistance to multiple drugs is increasing at an alarming rate in the current era and nanotechnology is one of the effective and novel approaches to overcome drug resistance. METHODS: Zinc Oxide Nanoparticles (ZnO NPs) have stronger antibacterial activity and are regarded as bio-safe nanomaterial. The aim of the present study is to synthesize the ZnO NPs using Aloe vera leaves extract and to investigate the synergistic effects and antioxidant actions of biosynthesized ZnO NPs against gram-negative bacteria E.coli and K. pneumoniae. The synergistic effect of ß-lactam antibiotics (meropenem and ciprofloxacin) was tested along with ZnO NPs using Kirby's disc diffusion assay. The antioxidant activity was investigated by α, α-diphenyl-ß- picrylhydrazyl (DPPH) method. RESULTS: Results of the study revealed that the antibacterial activity of the selected antibiotics was much enhanced by ZnO NPs than the antibiotics alone. The resistant antibiotic (ciprofloxacin) became sensitive when combined with ZnO NPs. The antioxidant activity reveals that biosynthesized ZnO NPs possess significantly higher (p<0.05) antioxidant activity (77%). CONCLUSION: The findings reveal that biosynthesized ZnO NPs have a much more eco-friendly approach. It can act as a strong potentiator of ß-lactam antibiotics and put forward the possibility to use them effectively in targeted drug delivery, pharmaceuticals and biomedical fields.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Plantas Medicinais , Pneumonia , Óxido de Zinco , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bactérias , Ciprofloxacina , Escherichia coli , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Óxido de Zinco/farmacologia , beta-Lactamas
7.
J Oleo Sci ; 71(6): 875-879, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35661068

RESUMO

One of the principal mechanisms that contribute resistance to antibiotics is the production of extended spectrum beta lactamase (ESBL) in Gram negative bacteria. In the present study, molecular methods were used to evaluate the prevalence of the extended-spectrum beta-lactamase (ESBL)-encoding CTX-M gene among Gram negative bacterial strains. In total, 148 clinical samples were collected from different tertiary care hospitals of Lahore, Pakistan. Disc synergy diffusion method was used to detect the presence of ESBL production. Moreover, antibiotic resistance patterns and molecular detection of bla CTX-M ESBLs, were also studied. The pathogens isolated from the 148 samples included Escherichia coli (43%) followed by Klebsiella sp. (28%), Proteus sp. (18%) and Pseudomonas sp. (11%). In all 148 strains, 95 (64%) were ESBL producers while 53 (36%) were non ESBL producers. The strains which were phenotypically ESBL producers, bla CTX-M were found in 46% E. coli strains, while 50% Klebsiella sp. were harboring the gene. A high resistance rate was observed against cephalosporins (cefopodoxime 67%, cefoperazone 73%, cephalexin 63% sparaxin 61%). Lower resistance was observed against meropenem among all isolated bacterial strains. Genotypic detection of bla CTX-M genes by PCR revealed 46% of E. coli and 50% of Klebsiella strains harbored bla CTX-M gene. The present study showed that ESBLs producers were resistant to commonly used antibiotics. Similarly, bla CTX-M ESBL production is more prevalent in our clinical isolates.


Assuntos
Escherichia coli , beta-Lactamases , Antibacterianos/farmacologia , Escherichia coli/genética , Bactérias Gram-Negativas/genética , Hospitais , Testes de Sensibilidade Microbiana , Paquistão/epidemiologia , beta-Lactamases/genética
8.
J Oleo Sci ; 71(11): 1669-1677, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36310054

RESUMO

Biogenic synthesis of cobalt (Co) and copper (Cu) nanoparticles (NPs) was performed using the bacterial strains Escherichia coli and Bacillus subtilis. Prepared NPs were confirmed by a color change to maroon for CoNPs and green for CuNPs. The NPs characterization using FTIR showed the presence of functional groups, i.e., phenols, acids, protein, and aromatics present in the Co and CuNPs. UV-vis spectroscopy of E. coli and B. subtilis CuNPs showed peaks at 550 and 625 nm, respectively. For E. coli and B. subtilis CoNPs, peaks were observed at 300 nm and 350 nm, respectively. Antibacterial and antifungal activity of B. subtilis and E. coli Co and CuNPs was determined at 100 mg/mL concentration against two bacterial strains at 5, 2.5, and 1.5 mg/mL against fungal two strains F. oxysporum and T. viridi, respectively. B. subtilis CuNPs showed significantly higher inhibition zones (ZOI=25.7-29.7 mm) against E. coli and B. subtilis compared to other biogenic NPs. Likewise, B. Subtilis CuNPs showed lower MIC (4.3 ± 6.3) and MBC (5.3 mg/mL) values against both tested isolates. Antifungal activity of B. subtilis and E. coli CuNPs and CoNPs showed a concentration-dependent decrease in ZOI. Among all biogenic NPs, B. subtilis CoNPs showed the highest ZOI (25-30 mm) against F. oxysporum followed by E. coli CuNPs with maximum ZOI (20-27 mm) against T. viridi. Again, B. subtilis CoNPs and E. coli CuNPs showed lowest MIC and MFC values against both fungal isolates. In conclusion, the current study showed that biogenically synthesized B. subtilis Cu or CoNPs can be used as effective antimicrobial agents due to their potential antibacterial and antifungal potential.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Cobre/farmacologia , Cobre/química , Antifúngicos/farmacologia , Antifúngicos/química , Testes de Sensibilidade Microbiana , Cobalto/farmacologia , Escherichia coli/metabolismo , Nanopartículas Metálicas/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias
9.
Nutrients ; 14(16)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36014797

RESUMO

Mycoprotein is a fungal-based meat alternative sold in food retail in various countries around the world. The present study builds on a multi-national sample and uses partial least square structural equation modeling. The proposed conceptual model identified key factors that are driving and inhibiting consumer willingness to try, buy, and pay a price premium for mycoprotein. The results relate to the overall sample of 4088 respondents and to two subsample comparisons based on gender and meat consumption behavior. The results show that the biggest drivers of willingness to consume mycoprotein were healthiness, followed by nutritional benefits, safe to eat, and sustainability. Affordability and taste had mixed results. Willingness to consume mycoprotein was inhibited if nutritional importance was placed on meat and, to a lesser extent, if the taste, texture, and smell of meat were deemed important. Best practice recommendations address issues facing marketing managers in the food industry.


Assuntos
Comportamento do Consumidor , Paladar , Indústria Alimentícia , Carne , Inquéritos e Questionários
10.
Virol J ; 8: 296, 2011 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-21663685

RESUMO

Hepatitis C is an infectious disease, caused by blood borne pathogen; the Hepatitis C Virus. In this study we analyzed blood samples collected from various risk groups for the prevalence of anti-HCV and active HCV infection with the help of Immunochromtographic tests and nested PCR. The prevalence of active HCV infection among the high risk groups was 15.57% (26/167). The prevalence of HCV in individual risk groups was 15%, 28%, 8%, 14.28% and 14.28% in the case of thalassemics, dialysis, major surgery group, dental surgery group and injection drug users respectively. Our analysis reveals the fact that health care facilities in the Khyber Pakhtunkhwa province of Pakistan are contributing a great deal towards the spread of HCV infection.


Assuntos
Infecção Hospitalar/epidemiologia , Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Infecção Hospitalar/virologia , Feminino , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/virologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Imunoensaio/métodos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Reação em Cadeia da Polimerase/métodos , Prevalência , RNA Viral/sangue , Adulto Jovem
11.
World J Gastroenterol ; 14(2): 200-2, 2008 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-18186555

RESUMO

The c-Jun NH2-terminal Kinase (JNK) pathway represents one sub-group of the mitogen-activated protein (MAP) kinases which plays an important role in various inflammatory diseases states, including inflammatory bowel disease (IBD). Significant progress towards understanding the function of the JNK signaling pathway has been achieved during the past few years. Blockade of the JNK pathway with JNK inhibitors in animal models of IBD lead to resolution of intestinal inflammation. Current data suggest specific JNK inhibitors hold promise as novel therapies in IBD.


Assuntos
Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Transdução de Sinais/imunologia , Humanos
12.
Poult Sci ; 97(1): 289-293, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29112760

RESUMO

Overgrowth of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli (E. coli) on Campylobacter media prevents the latter's selective isolation, thereby making the improvement of Campylobacter-selective media necessary. We evaluated tazobactam (an ESBL inhibitor) to supplement Bolton enrichment broth (Tz-Bolton broth) for the selective isolation of Campylobacter in chicken carcass rinses. First, using 20 strains of ESBL-producing E. coli and 13 Campylobacter strains, we found 4 µg/mL of tazobactam to be optimal for inhibiting the ESBL-producing E. coli while allowing the growth of all tested Campylobacter strains. Next, 80 whole chicken carcasses were rinsed with buffered peptone water (BPW), and 25 mL of BPW rinse was mixed with 2 × blood-free Bolton broth (25 mL) with or without tazobactam followed by incubation at 42°C for 48 h under microaerobic conditions. A loopful of the incubated broth was inoculated on modified charcoal-cefoperazone-deoxycholate agar (mCCDA) and microaerobically incubated at 42°C for 48 h. The tazobactam supplemented Bolton broth showed a higher Campylobacter isolation rate (38.8%, p < 0.05) than normal Bolton broth (15%). Moreover, the number of mCCDA plates with non-Campylobacter was much lower (p < 0.05) after enrichment in Tz-Bolton broth (0%) than in the normal Bolton broth (80%), suggesting that selectivity of the modified broth was superior to normal Bolton broth.


Assuntos
Campylobacter/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Microbiologia de Alimentos/métodos , Carne/microbiologia , Ácido Penicilânico/análogos & derivados , Inibidores de beta-Lactamases/farmacologia , Animais , Técnicas Bacteriológicas/métodos , Galinhas/microbiologia , Meios de Cultura , Ácido Penicilânico/farmacologia , Tazobactam
13.
Gastroenterol Clin North Am ; 45(2): 317-31, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27261901

RESUMO

Approximately 36% of adult women in the United States are obese. Although obesity affects women similarly to men in terms of prevalence, there seem to be gender-specific differences in the pathophysiology, clinical manifestations, and treatment of obesity. Obesity is linked to comorbid diseases involving multiple organ systems, including the gastrointestinal tract, like gastroesophageal reflux disease, fatty liver disease, and gallstones. This article focuses on obesity in women, specifically the impact of obesity on gastrointestinal diseases and reproductive health, as well as the treatment of obesity in women.


Assuntos
Cálculos Biliares/epidemiologia , Refluxo Gastroesofágico/epidemiologia , Infertilidade Feminina/epidemiologia , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade/epidemiologia , Complicações na Gravidez/epidemiologia , Cirurgia Bariátrica , Dietoterapia , Gerenciamento Clínico , Terapia por Exercício , Feminino , Humanos , Obesidade/fisiopatologia , Obesidade/terapia , Gravidez , Saúde Reprodutiva
14.
Braz. arch. biol. technol ; 64: e21210018, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1360192

RESUMO

Abstract The bacteria residing in the gut of honey bees (HB) has demonstrated a significant role in protecting bees against various pathogens, production of honey and wax. However, no information exists about the antibacterial potential of bacterial isolates from gut of Asian HB, Apis cerana Indica F. (Hymenoptera: Apidae), against human pathogens. This study aims to investigate the antibacterial and multienzyme potential of aerobic bacteria from A. cerana gut using culture dependent approach. A total of 12 HB gut bacteria were characterized morphologically and biochemically. These strains were further screened for their antimicrobial activity against pathogenic human microorganisms Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Bacillus licheniformis and Bacillus subtilis using cross streak (primary screening) and agar well diffusion methods (secondary screening). Preliminary characterization of cell-free supernatant (CFS) of two promising isolates was performed by measuring lactic acid concentrations, enzymatic digestion of antimicrobial compounds, stability over a range of temperature, pH and amplification of spaS (subtilin) and spoA (subtilosin) genes. In primary screening, among 12 HB isolates, eight strains showed statistically significant highest zones of inhibition (p≤0.05) against E. coli, K. pneumoniae and P. aeruginosa. 16S rRNA sequencing revealed that these isolates belong to Bacillus genus, identified as B. tequilensis, B. pumilus, B. xiamenensis, B. subtilis, B. amyloliquefaciens, B. safensis, B. licheniformis, B. altitudinis (Accession numbers: MT186230-MT186237). Secondary screening revealed that among eight isolates, B. subtilis and B. amyloliquefaciens showed statistically significantly strong inhibition (p≤0.05) against all tested pathogens. Antibiotic susceptibility testing revealed that both isolates were resistant to antibiotics and possesses proteolytic, lipolytic and cellulolytic activities. The nature of the compound causing inhibitory activity was found to be proteinaceous and showed stability over a wide range of temperature as well as pH. PCR study confirmed the presence of bacteriocins by successful amplification of important antimicrobial peptide biosynthesis genes spaS and spoA. These results suggest that the HB gut is a home to bacteria that possess antimicrobial activity and important enzymes with antimicrobial potential. To our knowledge, this is the first report demonstrating the antimicrobial potential of bacteria isolated from gut of HB (A. cerana) against human pathogens.

17.
J Biotechnol ; 145(4): 323-9, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20026207

RESUMO

Drosophila Nanos gene plays an important role in stem cell maintenance and body patterning. With the purpose of understanding the cis-regulatory machinery involved in the transcription of the nanos gene in the germline stem cells, we examined its promoter fragment from +97 to -708 relative to the transcription start site and identified enhancer elements located between position -108 and +97. Experiments with transgenic flies revealed that the minimal promoter (from -108 to +20) is sufficient in the germline stem cells for the GFP expression in transgenic Drosophila. Moreover, the flag-tagged nanos protein blotting experiments revealed that a short promoter fragment plus some sequences of the nos 5'UTR spanning -108 to +97 could efficiently drive the expression of the flag-tagged [Nos-mRNA-nos3'UTR] transgene in transgenic flies indicating that the cis-regulatory elements located between positions -108 and +97 of the nanos promoter are sufficient to fully transcribe the nanos mRNA. Deletion of the identified cis-acting sequences from the promoter rendered it non-functional as it could no longer transcribe the nanos mRNA in transgenic flies thus revealing the importance of these sequences for the transcription of the nanos gene.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Células Germinativas/citologia , Regiões Promotoras Genéticas/genética , Proteínas de Ligação a RNA/genética , Células-Tronco/metabolismo , Animais , Sequência de Bases , Western Blotting , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Deleção de Sequência , Células-Tronco/citologia , Transcrição Gênica
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