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BACKGROUND AND PURPOSE: Data from randomly controlled trials have indicated that a decompressive hemicraniectomy is more clinically effective than medical treatment in the management of space-occupying brain oedema post middle cerebral artery infarction. This economic evaluation compares the impact of the two options in the UK. No recent study has conducted an economic evaluation on this topic for the UK. METHOD: A cost-utility analysis over a time period of 1 year was used, measuring benefits in terms of quality adjusted life years (QALYs) and costs in pound sterling, discounted to 2015 prices. The evaluation was from the perspective of the National Health Service, the largest healthcare provider in the UK. RESULTS: The cost-utility analysis found an incremental cost effectiveness of £116 595.10 for every QALY gained if patients were offered a decompressive hemicraniectomy compared to the best medical treatment. DISCUSSION: This is above the National Institute for Health and Care Excellence (NICE) 'cost-effective' threshold of £20 000-£30 000 per QALY, but lower mortality rates associated with the surgical alternative raises ethical considerations for healthcare providers in the UK.
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Edema Encefálico/cirurgia , Craniotomia/economia , Infarto da Artéria Cerebral Média/cirurgia , Análise Custo-Benefício , Craniotomia/métodos , Feminino , Humanos , Masculino , Anos de Vida Ajustados por Qualidade de Vida , Resultado do TratamentoRESUMO
BACKGROUND: Arteriovenous graft (AVG) infections can present as major life-threatening hemorrhage or sepsis in a chronic kidney disease patient. Frequently, all these patients present in critical condition which need prompt and expeditious management. Various procedures are described for management of infected grafts and its bleeding complications. However, these procedures are associated with postop-operative bleeding and persistent infection. The aim was to study brachial artery ligation (BAL) near the elbow joint in the management of an infected AVG. METHODS: It was a retrospective study where data collection was done for 51 patients who underwent BAL in infected AVGs from January 2007 to December 2016. RESULTS: During the study period, AVG infections were treated in 62 patients. Fifty-one BALs were done in 62 limbs treated. All were arm grafts (brachial artery to axillary vein) using expanded polytetrafluoroethylene grafts. In 49 patients, BAL was done as a primary procedure. In 2 patients, BAL was done after they presented with uncontrolled infection after initial subtotal excision with oversewing of graft stump at arterial anastomosis. There were 36 men and 15 women, with a mean age of 49 years (range, 23-82). The primary etiologies for renal failure were hypertension (56.2%), diabetes (34.3%), and others (9.5%). Follow-up was 100% at 1 month and 82.3% (42 patients) at 3 months, and none showed any signs of ischemia or sepsis. All had biphasic signals in radial and ulnar arteries with normal peripheral capillary oxygen saturation readings in fingers. None of the patients underwent additional interventions. CONCLUSIONS: BAL in AVG infections is a safe alternative considering the critical general condition of chronic kidney disease patient. It reduces the operative time significantly and avoids complex revascularization and anastomotic dehiscence without any ischemic or bleeding complications. BAL near the elbow joint in patients with good back-bleeding can be used as a primary approach in an infected AVG. However, close monitoring of patient in postoperative period is essential.
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Derivação Arteriovenosa Cirúrgica/efeitos adversos , Veia Axilar/cirurgia , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Prótese Vascular/efeitos adversos , Artéria Braquial/cirurgia , Infecções Relacionadas à Prótese/cirurgia , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Veia Axilar/diagnóstico por imagem , Veia Axilar/fisiopatologia , Perda Sanguínea Cirúrgica/prevenção & controle , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiopatologia , Feminino , Humanos , Ligadura , Masculino , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/etiologia , Hemorragia Pós-Operatória/prevenção & controle , Infecções Relacionadas à Prótese/diagnóstico por imagem , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Essentials This study examined vein wall remodeling in acute thrombosis and postthrombotic syndrome (PTS). Thrombus-wall interface was measured using ultrasound real-time high definition zoom. Experimental cohorts demonstrated increased vein wall thickness localized to affected segments. Presence of thrombus or PTS are the most important factors affecting wall thickening. SUMMARY: Introduction A few studies have investigated venous wall remodeling after venous thrombosis by using rodent models. Such information is lacking in humans. This study was designed to determine the acute and chronic effects of thrombus on the vein wall. Methods Patients aged > 16 years with deep vein thrombosis diagnosed by duplex ultrasound were assessed by the use of case-control methodology. Those with recurring thrombotic episodes, cardiorespiratory disease, terminal cancer, morbid obesity, penetrating trauma or significant inflammation were excluded. High-resolution ultrasound was employed to determine wall thickness, with strict quality criteria and inclusion of only technically adequate ultrasound images. Results Data were collected from patients with acute thrombosis (35), patients with chronic postthrombotic changes (15), and unaffected controls (32), with 853 total vein segments being analyzed. As compared with controls (mean 0.37 mm; 95% confidence interval [CI] 0.37-0.38 mm), venous wall thickness was increased in acute (mean 0.63 mm; 95% CI 0.61-0.64 mm) and postthrombotic (mean 0.85 mm; 95% CI 0.80-0.91 mm) venous segments. Ipsilateral, contralateral and unaffected control vein segments were not different. Ipsilateral segments were thicker than controls in postthrombotic syndrome (PTS) patients, but not in acute patients. Multiple regression analyses demonstrated small impacts of age and sex on vein wall thickness. Conclusions Wall thickness increases in all lower-tcglimb venous segments of patients with acute and postthrombotic disease. Age and sex may affect wall thickness, although further investigation is required to clarify their impact. The equivalence of ipsilateral and unaffected control segments suggests that acute vein wall remodeling is mediated through direct interaction with the thrombus, whereas remodeling in PTS patients may be affected by other factors.
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Extremidade Inferior/irrigação sanguínea , Síndrome Pós-Trombótica/patologia , Remodelação Vascular , Veias/fisiologia , Trombose Venosa/patologia , Doença Aguda , Adulto , Fatores Etários , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome Pós-Trombótica/diagnóstico por imagem , Estudos Prospectivos , Fatores Sexuais , Ultrassonografia Doppler Dupla , Veias/diagnóstico por imagem , Trombose Venosa/diagnóstico por imagemRESUMO
Several polymerase chain reaction (PCR)-based methods are available for isolation of unknown genomic fragments. In the present study, a comparative evaluation of a few methods of ligation-mediated PCR methods and a ligation-independent one were made by isolating promoter fragment for N-methyltransferase gene involved in the caffeine biosynthetic pathway of Coffea canephora. The benefits of tertiary PCR and the effects of a 4-base cutting restriction endonuclease on the size of the PCR products obtained were demonstrated in one of the ligation-mediated PCR methods. The methods adopted in this study differed in the sizes of the 5'-flanking regions obtained. The efficiencies of various methods used reflect the inherent limitations of the PCR-based methods for isolation of unknown flanking regions.
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Região 5'-Flanqueadora , Biotecnologia/métodos , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Passeio de Cromossomo , Coffea/genética , Coffea/metabolismo , DNA de Plantas/química , Estudos de Avaliação como Assunto , Genes de Plantas , Metiltransferases/genética , Regiões Promotoras GenéticasRESUMO
INTRODUCTION: Prevalence of metabolic syndrome (MetS) in the Indian population varies from 31.6 to 41.1%. Indians, without being conventionally obese, but inherently insulin resistant, have higher risk of developing cardiovascular diseases and diabetes. Since military aircrew, belonging to the same ethnic pool, may reflect similar prevalence of MetS as the general Indian populace, this study was undertaken to find the prevalence of MetS among Indian military aircrew using one candidate definition. METHODS: In this cross sectional descriptive study, 210 military aircrew voluntarily participated. Besides demographic and lifestyle related details, their anthropometric measurements, including height, weight, waist circumference, hip circumference, and skin fold thickness were recorded. Body mass index and waist-to-hip ratio were deduced from the recorded measurements. Resting heart rate and blood pressure were recorded and appropriate laboratory investigations were undertaken. RESULTS: Prevalence of MetS, as per chosen definition, was 33.3% (N = 70), which had moderate, fair, and slight agreement with NCEP ATP III (k = 0.43), IDF (k = 0.27), and WHO (k = 0.15) definitions, respectively. Decadal prevalence of MetS was found to be highest in the fourth decade (46.8%), followed by the third decade (41.3%). CONCLUSION: Reported prevalence of MetS highlights an urgent need to define preventive strategies to minimize loss of trained manpower among military aircrew. Flight surgeons have an important role to play to educate aircrew about modifying their lifestyle to reduce morbidity and mortality among themselves in the future. Sharma S, Chandrashekar AM, Singh V. Metabolic syndrome in military aircrew using a candidate definition. Aerosp Med Hum Perform. 2016; 87(9):790-794.
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Síndrome Metabólica/epidemiologia , Militares/estatística & dados numéricos , Pilotos/estatística & dados numéricos , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Estudos Transversais , Exercício Físico , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fumar/epidemiologia , Adulto JovemRESUMO
A series of novel 2,5-disubstituted-1,3,4-oxadiazole derivatives were synthesized and screened for their antimicrobial and antioxidant activities. The assay indicated that compounds 3c, 3d, and 3i exhibited comparable antibacterial and antioxidant activity with first-line drugs. The structure activity relationship and molecular docking study of the synthesized compounds are also reported.
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N-Methyltransferases (NMTs) catalyze the three SAM dependent sequential methylation of xanthosine, producing caffeine in Coffea species. In the present work, a PCR based genome walking method was adopted to isolate and clone the promoter for the NMT gene. Inspection of the promoter sequence revealed the presence of several motifs important for the regulation of the gene expression. The whole fragment was fused to the beta-glucuronidase (gus) reporter gene and used in Agrobacterium tumefaciens mediated transformation of Nicotiana tabacum. GUS assays proved that the isolated promoter was able to direct the expression of the reporter gene in transgenic tobacco. Based on the promoter sequence, primer was designed and the genomic fragment comprising the promoter and its corresponding gene was amplified and cloned. Sequencing of one of the genomic clones revealed the presence of four exons and three introns in NMT gene. The differences in the restriction pattern among the genomic clones were studied using PCR-RFLP. This is the first report of cloning of the promoter for a gene involved in caffeine biosynthetic pathway and it opens up the possibility of studying the molecular mechanisms that regulate the production of caffeine.
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Cafeína/biossíntese , Coffea/genética , Metiltransferases/genética , Regiões Promotoras Genéticas , Agrobacterium tumefaciens/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Códon de Iniciação , Coffea/metabolismo , Primers do DNA , Éxons , Glucuronidase/genética , Glucuronidase/metabolismo , Íntrons , Metiltransferases/metabolismo , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Nicotiana/genética , Transformação GenéticaRESUMO
Contamination of food and feedstuffs by Aspergillus species and their toxic metabolites is a serious problem as they have adverse effects on human and animal health. Hence, food contamination monitoring is an important activity, which gives information on the level and type of contamination. A PCR-based method of detection of Aspergillus species was developed in spiked samples of sterile maize flour. Gene-specific primers were designed to target aflR gene, and restriction fragment length polymorphism (RFLP) of the PCR product was done to differentiate Aspergillus flavus and Aspergillus parasiticus. Sterile maize flour was inoculated separately with A. flavus and A. parasiticus, each at several spore concentrations. Positive results were obtained only after 12-h incubation in enriched media, with extracts of maize inoculated with A. flavus (101 spores/g) and A. parasiticus (104 spores/g). PCR products were subjected to restriction endonuclease (HincII and PvuII) analysis to look for RFLPs. PCR-RFLP patterns obtained with these two enzymes showed enough differences to distinguish A. flavus and A. parasiticus. This approach of differentiating these two species would be simpler, less costly and quicker than conventional sequencing of PCR products.
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Aspergillus/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Zea mays/microbiologia , Aspergillus/classificação , Aspergillus/genética , Aspergillus flavus/classificação , Aspergillus flavus/genética , Aspergillus flavus/isolamento & purificação , DNA Fúngico/análise , Proteínas de Ligação a DNA/isolamento & purificação , Contaminação de Alimentos/análise , Proteínas Fúngicas/isolamento & purificação , Sensibilidade e Especificidade , Especificidade da Espécie , Esporos Fúngicos , Fatores de Tempo , Fatores de Transcrição/isolamento & purificaçãoRESUMO
Isolates of Bacillus cereus from traditional Indian foods were detected by colony hybridization using the PCR-generated phospholipase (PL-1) probe. In all, 29 isolates picked up by the probe were confirmed as B. cereus by conventional cultural and biochemical characteristics. All the isolates reacted positively in PCR with phospholipase (PL-1) primers. Among the native isolates, 11 of them showed the discontinuous pattern of haemolysin BL activity in gel diffusion assay. Though 14 isolates reacted positively in PCR with primers (Ha-1) specific to the B gene of haemolysin BL, only four of them showed both the presence of gene and haemolysin BL activity. More than 50% of the isolates indicated their potential enterotoxigenicity by reacting positively with primers specific for the BceT gene encoding for diarrhoeal enterotoxin. PCR with primers for different inverse (IS) repeat elements revealed that isolates carrying transposon IS 231-P 231-1 did not carry IS 240-P 240. Some of the isolates were devoid ofthese IS elements. The study demonstrated the potential of using of a PCR-generated labelled PL-1 probe for the direct detection of B. cereus in food samples and PCR for characterizing the toxigenic isolates.
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Bacillus cereus/isolamento & purificação , DNA Bacteriano/análise , Bacillus cereus/enzimologia , Bacillus cereus/genética , Sequência de Bases , Primers do DNA , Microbiologia de Alimentos , Amplificação de Genes , Técnicas de Sonda Molecular , Dados de Sequência Molecular , Fosfolipases , Reação em Cadeia da PolimeraseRESUMO
Research on antifungal proteins and other mechanisms that provide the biochemical basis for host-plant resistance to stalk rot and grain molds is reviewed in this paper. Stalk rot caused by Fusarium species leads to substantial yield loss due to poor grain filling and/or lodging. A transgenic sorghum expressing high levels of chitinase exhibited less stalk rot development when exposed to conidia of F. thapsinum. Grain mold of sorghum is associated with warm humid environments and results from colonization by several fungi (F. thapsinum, Curvularia lunata, and Alternaria alternata) of the developing caryopsis. The roles of several biochemical mechanisms (tannins, phenolic compounds, red pericarp, proteins, hard endosperm, and antifungal proteins) on grain mold resistance are discussed. Resistance mechanisms related to these compounds appear to be additive, and pyramiding of genes is a feasible approach to limit grain deterioration. Several experimental approaches are proposed to extend current findings.
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Antifúngicos/farmacologia , Grão Comestível/microbiologia , Doenças das Plantas , Proteínas de Plantas/farmacologia , Antifúngicos/análise , Aspergillus/efeitos dos fármacos , Quitinases/análise , Grão Comestível/química , Grão Comestível/genética , Fusarium/efeitos dos fármacos , Marcadores Genéticos , Glicosídeo Hidrolases/análise , Fenóis/análise , Doenças das Plantas/genética , Proteínas de Plantas/análise , Taninos/análiseRESUMO
Despite the continuous improvement of dialysis technology and pharmacological treatment, mortality rates for dialysis patients are still high. A 2-year prospective study was conducted at a tertiary care hospital to determine the factors influencing survival among patients on maintenance hemodialysis. 96 patients with end-stage renal disease surviving more than 3 months on hemodialysis (8-12 h/week) were studied. Follow-up was censored at the time of death or at the end of 2-year study period, whichever occurred first. Of the 96 patients studied (mean age 49.74 ± 14.55 years, 75% male and 44.7% diabetics), 19 died with an estimated mortality rate of 19.8%. On an age-adjusted multivariate analysis, female gender and hypokalemia independently predicted mortality. In Cox analyses, patient survival was associated with delivered dialysis dose (single pool Kt/V, hazard ratio [HR] =0.01, P = 0.016), frequency of hemodialysis (HR = 3.81, P = 0.05) and serum albumin (HR = 0.24, P = 0.005). There was no significant difference between diabetes and non-diabetes in relation to death (Relative Risk = 1.109; 95% CI = 0.49-2.48, P = 0.803). This study revealed that mortality among hemodialysis patients remained high, mostly due to sepsis and ischemic heart disease. Patient survival was better with higher dialysis dose, increased frequency of dialysis and adequate serum albumin level. Efforts at minimizing infectious complications, preventing cardiovascular events and improving nutrition should increase survival among hemodialysis patients.
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We present our preliminary results of remote endarterectomy performed during June 2003 to June 2010. 8 cases of unilateral ileofemoral disease, 3 cases of bilateral ileofemoral disease and 4 cases of femoro-popliteal disease constituting 18 limbs were successfully operated. All patients had comorbid conditions like Diabetes mellitus, hypertension, cardiac disease and smoking. Patency at 3 months with loss of one patient for follow up was 100 %. At one year follow up, the overall success rate was 90.90 %. One patient with Iliofemoral Endarterectomy had progression of the disease and hence had to undergo Aorto-Femoral bypass. All patients who had tissue loss, showed complete recovery by 3 months and one patient was lost to follow up. A 5 year follow up had a patency rate of 74 %. Remote endarterectomy is a viable and durable alternative to standard bypass procedures. Remote endarterectomy combines the advantages of minimally invasive surgery with endovascular techniques.
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The first successful Agrobacterium-mediated transformation of the green alga Haematococcus pluvialis Flot. using the binary vectors hosting the genes coding for GUS (ß-glucuronidase), GFP (green fluorescent protein), and hpt (hygromycin phosphotransferase) is reported here. Colonies resistant to hygromycin at 10 mg · L(-1) expressed ß-glucuronidase. The greenish yellow fluorescence of GFP was observed when the hygromycin-resistant cells were viewed with a fluorescent microscope. PCR was used to successfully amplify fragments of the hpt (407 bp) and GUS (515 bp) genes from transformed cells, while Southern blots indicated the integration of the hygromycin gene into the genome of H. pluvialis. SEM indicated that the cell wall of H. pluvialis was altered on infection with Agrobacterium. The transformation achieved here by Agrobacterium does not need treatment with acetosyringone or the wounding of cells. A robust transformation method for this alga would pave the way for manipulation of many important pathways relevant to the food, pharmaceutical, and nutraceutical industries.
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Expression of Pseudomonas aeruginosa genes PHA synthase1 (phaC1) and (R)-specific enoyl CoA hydratase1 (phaJ1) under a lacZ promoter was able to support production of a copolymer of Polyhydroxybutyrate (PHB) and medium chain length polyhydoxyalkanoates (mcl-PHA) in Escherichia coli. In order to improve the yield and quality of PHA, plasmid bearing the above genes was introduced into E. coli JC7623, harboring integrated beta-ketothiolase (phaA) and NADPH dependent-acetoacetyl CoA reductase (phaB) genes from a Bacillus sp. also driven by a lacZ promoter. The recombinant E. coli (JC7623ABC1J1) grown on various fatty acids along with glucose was found to produce 28-34% cellular dry weight of PHA. Gas chromatography and (1)H Nuclear Magnetic Resonance analysis of the polymer confirmed the ability of the strain to produce PHB-co-Hydroxy valerate (HV)-co-mcl-PHA copolymers. The ratio of short chain length (scl) to mcl-PHA varied from 78:22 to 18:82. Addition of acrylic acid, an inhibitor of beta-oxidation resulted in improved production (3-11% increase) of PHA copolymer. The combined use of enzymes from Bacillus sp. and Pseudomonas sp. for the production of scl-co-mcl PHA in E. coli is a novel approach and is being reported for the first time.
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Bacillus/enzimologia , Escherichia coli/metabolismo , Engenharia Genética/métodos , Poli-Hidroxialcanoatos/biossíntese , Pseudomonas/enzimologia , Acetil-CoA C-Aciltransferase/genética , Acetil-CoA C-Aciltransferase/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Bacillus/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biomassa , Biopolímeros/biossíntese , Biopolímeros/química , Biopolímeros/genética , Vias Biossintéticas , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Expressão Gênica , Poli-Hidroxialcanoatos/química , Poli-Hidroxialcanoatos/genética , Pseudomonas/genéticaRESUMO
AIMS: The objective of the present work was to utilize an unrefined natural substrate namely mahua (Madhuca sp.) flowers, as a carbon source for the production of bacterial polyhydroxyalkanoate (PHA) copolymer by Bacillus sp-256. METHODS AND RESULTS: In the present work, three bacterial strains were tested for PHA production on mahua flower extract (to impart 20 g l(-1) sugar) amongst which, Bacillus sp-256 produced higher concentration of PHA in its biomass (51%) compared with Rhizobium meliloti (31%) or Sphingomonas sp (22%). Biosynthesis of poly(hydroxybutyrate-co-hydroxyvalerate) - P(HB-co-HV)--of 90 : 10 mol% by Bacillus sp-256 was observed by gas chromatographic analysis of the polymer. Major component of the flower is sugars (57% on dry weight basis) and additionally it also contains proteins, vitamins, organic acids and essential oils. The bacterium utilized malic acid present in the substrate as a co-carbon source for the copolymer production. The flowers could be used in the form of aqueous extract or as whole flowers. PHA content of biomass (%) and yield (g l(-1)) in a 3.0-l stirred tank fermentor after 30 h of fermentation under constant pH (7) and dissolved oxygen content (40%) were 54% and 2.7 g l(-1), respectively. Corresponding yields for control fermentation with sucrose as carbon source were 52% and 2.5 g l(-1). The polymer was characterized by proton NMR. CONCLUSIONS: Utilization of mahua flowers, a natural substrate for bacterial fermentation aimed at PHA production, had additional advantage, as the sugars and organic acids present in the flowers were metabolized by Bacillus sp-256 to synthesize P(HB-co-HV) copolymer. SIGNIFICANCE AND IMPACT OF THE STUDY: Literature reports on utilization of suitable cheaper natural substrate for PHA copolymer production is scanty. Mahua flowers used in the present experiment is a cheaper carbon substrate compared with several commercial substrates and it is rich in main carbon as well as co-carbon sources that can be utilized by bacteria for PHA copolymer production.
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Bacillus/metabolismo , Reatores Biológicos , Madhuca/metabolismo , Poliésteres/metabolismo , Bacillus/crescimento & desenvolvimento , Biomassa , Carboidratos/análise , Meios de Cultura , Fermentação , Flores , Malatos/farmacologia , Extratos Vegetais/farmacologia , Ácido Succínico/farmacologiaRESUMO
A system for genetic transformation of Coffea canephora by co-cultivation with Agrobacterium rhizogenes harbouring a binary vector has been developed. The objective of the present study was the genetic transformation and direct regeneration of transformants through secondary embryos bypassing an intervening hairy root stage. Transformants were obtained with a transformation efficiency up to 3% depending on the medium adjuvant used. A. rhizogenes strain A4 harbouring plasmid pCAMBIA 1301 with an intron uidA reporter and hygromycin phosphotransferase (hptII) marker gene was used for sonication-assisted transformation of Coffea canephora. The use of hygromycin in the secondary embryo induction medium allowed the selection of transgenic secondary embryos having Ri T-DNA along with the T-DNA from the pCAMBIA 1301 binary vector. In addition transgenic secondary embryos devoid of Ri-T-DNA but with stable integration of the T-DNA from the binary vector were obtained. The putative transformants were positive for the expression of the uidA gene. PCR and Southern blot analysis confirmed the independent, transgenic nature of the analysed plants and indicated single and multiple locus integrations. The study clearly demonstrates that A. rhizogenes can be used for delivering transgenes into tree species like Coffea using binary vectors with Agrobacterium tumefaciens T-DNA borders.
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Coffea/genética , Coffea/fisiologia , Fenótipo , Raízes de Plantas/genética , Regeneração , Rhizobium/genética , Transformação Genética , Southern Blotting , Meios de Cultura , DNA Bacteriano/genética , Desenvolvimento Embrionário , Vetores Genéticos , Glucuronidase/metabolismo , Hipocótilo/microbiologia , Íntrons/genética , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , Sementes/citologiaRESUMO
A native isolate Lactobacillus farciminis MD isolated from fermenting mushroom exhibited a high degree of sensitivity to the majority of the bacteriocins produced by strains of lactobacilli, leuconostoc and pediococci. Also, the efficacy of Lact. farciminis MD as a sensitive strain for antibiotic assay was established against different antibiotics including ampicillin, cefazoline, chloramphenicol and nitrofurantoin at concentrations of 30 microg each, showing an inhibition zone of 30 mm diameter. The high degree of sensitivity towards bacteriocins and antibiotics provide potential for the exploitation of Lact. farciminis MD in establishing very well-defined bacteriocin producers.
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Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Lactobacillus/efeitos dos fármacos , Agaricales , Bacteriocinas/biossíntese , Fermentação , Microbiologia de Alimentos , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Leuconostoc/metabolismo , Testes de Sensibilidade Microbiana , Pediococcus/metabolismoRESUMO
AIMS: To evaluate the use of a staphylococcal accessory gene regulator (sar) as a means of detecting enterotoxigenic staphylococci. METHODS AND RESULTS: SarA gene-specific primers were designed and applied in PCR, which resulted in the detection of 49 sar-positive isolates from a total of 67 natural food isolates of staphylococci. Colony hybridization using PCR-generated Digoxigenin (DIG)-labelled sarA probe tested in spiked samples of khoa (a traditional heat-concentrated milk product) comprising a mixed microflora ensured the specificity of the probe. Validation experiments with the commercial samples of khoa also demonstrated the specificity of the probe. PCR characterization for enterotoxins A-D revealed the presence of at least one of the toxin-encoding genes in all the sarA-positive isolates tested. CONCLUSION: The study indicated that sarA gene could be an ideal marker gene either in colony hybridization or in PCR, for an effective detection of potentially enterotoxigenic strains of staphylococci in a food system. SIGNIFICANCE AND IMPACT OF THE STUDY: As an alternative to targeting the individual toxin genes, a regulatory gene responsible for controlling the synthesis of various virulence factors may be a suitable target gene for screening potentially toxigenic staphylococci in food system using nucleic acid-based methods.
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Proteínas de Bactérias/genética , Enterotoxinas/biossíntese , Microbiologia de Alimentos , Genes Bacterianos , Staphylococcus/genética , Transativadores/genética , Animais , DNA Bacteriano/isolamento & purificação , Enterotoxinas/genética , Marcadores Genéticos , Humanos , Leite/microbiologia , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade , Staphylococcus/isolamento & purificação , Staphylococcus/metabolismo , Staphylococcus/patogenicidade , Virulência/genéticaRESUMO
AIMS: The aim of the work was to develop efficient method to identify polyhydroxyalkanoate (PHA)-producing species of Bacillus from numerous soil isolates of bacteria. Identification of the isolates and characterization of the PHA produced by strains positive on the polymerase chain reaction (PCR) was envisaged. METHODS AND RESULTS: Different bacteria isolated from soil were screened by PCR using two sets of primers designed for Bacillus megaterium. Amongst 23 isolates examined, the DNA of 12 isolates reacted positively with the primers giving amplicons identical in size to that obtained from B. megaterium. The isolates which were identified as strains of B. sphaericus, B. circulans, B. brevis and B. licheniformis, produced 11- 41% of PHA in biomass, in sucrose-containing medium, over a growth period of 24-72 h. The nature of the PHA thus produced was analyzed by Fourier transform infrared spectroscopy, gas chromatography and by nuclear magnetic resonance (NMR) and found to contain polyhydroxy butyrate and polyhydroxyvalerate. CONCLUSIONS: The results indicate that most of our isolates from different species contained the B. megaterium type of PHA synthase. Bacillus licheniformis appeared to belong to another group as it did not react with both sets of primers. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows the universality of the B. megaterium type of PHA synthase in soil isolates of Bacillus. Some variations were also found.