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1.
Artículo en Inglés | MEDLINE | ID: mdl-38966517

RESUMEN

We present an interesting and complex case of cardiac tamponade due to uremic pericarditis (UP), resolving with intensive hemodialysis (HD). HD should be considered as first line management for patients with UP and pericardial effusion. Intensification of HD should be considered based on clinical presentation and severity of presentation.

2.
Eur Heart J Case Rep ; 7(11): ytad578, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38034938

RESUMEN

Background: Direct lightning strikes are rare, and multiple organ systems can be involved. Prognosis is dependent on the severity of the injury. Severe myocardial injury associated with transient electrocardiogram changes, which have been previously described, is a hazardous complication. Case summary: A 35-year-old man with no known past medical history presented unresponsive following a direct lightning strike while sitting in a portable toilet. High-quality cardiopulmonary resuscitation was started in the field, with return of spontaneous circulation (ROSC) after 1 h. Following ROSC, he received volume resuscitation and was maintained on multiple vasopressors. Electrocardiogram showed significant ST-elevations in inferior leads with elevated troponin I, consistent with inferior ST-elevation myocardial infarction. Labs revealed lactic acidosis, hyperkalaemia, acute kidney, and liver injury. Due to concern for plaque rupture, coronary angiography was performed and revealed no obstructive coronary artery disease. Vasopressor support and volume resuscitation were continued for extensive burns covering greater than 30% body surface area. The patient became progressively hypotensive, eventually precipitating pulseless electrical activity arrest. Emergent labs were notable for severe acidaemia. Despite aggressive interventions, he expired due to severe multi-organ failure. Discussion: Direct lightning injuries are rare with serious potential complications. Myocardial damage, either from direct electrical insult or from induced coronary vasospasm, can lead to multi-organ system failure.

3.
J AOAC Int ; 106(4): 866-872, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-36929921

RESUMEN

BACKGROUND: Azelastine HCl (AZ) and fluticasone propionate (FL) nasal spray drug product is commonly used in the treatment of allergic rhinitis worldwide. To date, the impurity profiling of this product has not been reported. OBJECTIVE: The present study aimed to develop and validate a novel RP-HPLC stability-indicating analytical method for the estimation of impurities from AZ and FL nasal spray drug product. METHODS: A mixture of octane sulfonic acid sodium salt and trifluroacetic acid is used as a mobile phase A. Acetonitrile is used as a mobile phase B. Good separation was achieved on Baker bond phenyl hexyl, 250 × 4.6, 5 µm column at 1 mL/min flow rate in gradient elution mode. The chromatograms were monitored at 239 nm. RESULTS: The LOD and LOQ were found to be 0.006 and 0.019 µg/mL for AZ and 0.010 and 0.030 µg/mL for FL, respectively. The correlation coefficient for all the known impurities and principal analytes was 0.999 from LOQ level to 150% of standard concentration. The recovery for all the known impurities was found to be between 90 and 110%. In the stress study, 15% degradation was observed in basic conditions and 8.7% in acidic conditions. No significant degradation was observed in thermal and oxidative conditions. CONCLUSION: An impurity profiling method for AZ and FL combination nasal spray product was successfully developed, validated, and demonstrated to be accurate, precise, specific, robust, and stability-indicating. The method can be routinely used for impurity testing of commercial batches in QC laboratories in the pharmaceutical industry. HIGHLIGHTS: No impurity study has been reported for this combination product until now.


Asunto(s)
Rociadores Nasales , Ftalazinas , Fluticasona , Cromatografía Líquida de Alta Presión/métodos , Ftalazinas/uso terapéutico
4.
Biotechnol Lett ; 44(7): 831-843, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35608787

RESUMEN

PURPOSE: In the wake of SARS-CoV-2's global spread, human activities from health to social life to education have been affected. Favipiravir and Molnupiravir exhibited novel hexokinase inhibition and we discuss advantages of this property in their COVID-19 inhibition potential. METHODS: This paper describes molecular docking data of human hexokinase II with Favipiravir, Cyan 20, Remdesivir, 2DG, and Molnupiravir along with hexokinase inhibition assays. RESULTS: Favipiravir, an antiviral drug previously cleared for treating the flu and ebola, has shown some promise in early trials to treat COVID-19. We observed potent human hexokinase inhibiting potential of Favipiravir (50%) as against 4% and merely 0.3% hexokinase inhibition with Molnupiravir and 2 Deoxy D glucose at 0.1 mM concentration supported by molecular docking studies. CONCLUSION: Favipiravir could continue to be part of the COVID-19 treatment regimen due to its resistance to host esterases, hexokinase inhibition potential and proven safety through human trials.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Amidas , Antivirales/farmacología , Citidina/análogos & derivados , Desoxiglucosa/farmacología , Hexoquinasa , Humanos , Hidroxilaminas , Simulación del Acoplamiento Molecular , Pirazinas , SARS-CoV-2
5.
Eur Heart J Case Rep ; 5(7): ytab195, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34557625

RESUMEN

BACKGROUND: Barth syndrome (BTHS) is a rare X-linked recessive disorder characterized by clinical features including cardiomyopathy, skeletal myopathy, neutropenia, growth delay, and exercise intolerance. It is often considered to be a paediatric disease, owing to most cases being diagnosed during childhood and mortality being the highest during the first few years of life. CASE SUMMARY: We report a case of dilated cardiomyopathy due to BTHS in a 27-year-old adult male patient, who initially presented with lightheadedness, dyspnoea, orthopnoea, and bilateral lower extremity oedema. Key findings from investigations included leukopenia, prolonged QTc interval, reduced left ventricular ejection fraction (LVEF), global enlargement of all heart chambers, patent coronary arteries, and mild pulmonary hypertension. The patient was diuresed to euvolemia and discharged with a LifeVest. Guideline-directed medical therapy was initiated and uptitrated as an outpatient. A repeat echocardiogram 2 years after initial presentation showed marked improvement in LVEF. DISCUSSION: It is possible that there are adult patients with idiopathic cardiomyopathy, which may be attributable to BTHS. In the absence of an obvious underlying cause, with the appropriate historical information, clinical exam, laboratory investigations, and imaging findings, BTHS should be considered as a likely cause of non-ischaemic cardiomyopathy.

6.
Ann Hematol ; 100(3): 667-673, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33439304

RESUMEN

The severe pneumonia caused by the human coronavirus (hCoV)-SARS-CoV-2 has inflicted heavy casualties, especially among the elderly and those with co-morbid illnesses irrespective of their age. The high mortality in African-Americans and males, in general, raises the concern for a possible X-linked mediated process that could affect the viral pathogenesis and the immune system. We hypothesized that G6PD, the most common X-linked enzyme deficiency, associated with redox status, may have a role in severity of pneumonia. Retrospective chart review was performed in hospitalized patients with COVID19 pneumonia needing supplemental oxygen. A total of 17 patients were evaluated: six with G6PD deficiency (G6PDd) and 11 with normal levels. The two groups (normal and G6PDd) were comparable in terms of age, sex, co-morbidities, and laboratory parameters-LDH, IL-6, CRP, and ferritin, respectively. Thirteen patients needed ventilatory support ; 8 in the normal group and 5 in the G6PDd group (72% vs.83%). The main differences indicating increasing severity in normal vs. G6PDd groups included G6PD levels (12.2 vs. 5.6, P = 0.0002), PaO2/FiO2 ratio (159 vs. 108, P = 0.05), days on mechanical ventilation (10.25 vs. 21 days P = 0.04), hemoglobin level (10 vs. 8.1 P = 0.03), and hematocrit (32 vs. 26 P = 0.015). Only one patient with G6PDd died; 16 were discharged home. Our clinical series ascribes a possible biological role for G6PDd in SARS-CoV2 viral proliferation. It is imperative that further studies are performed to understand the interplay between the viral and host factors in G6PDd that may lead to disparity in outcomes. KEY POINTS: • COVID19 studies show higher mortality in men, due to severe pneumonia and ARDS, indicating possible X-linked mediated differences • G6PD, the most common X-linked enzymopathy, highly prevalent in African Americans and Italians, maintains redox homeostasis. • Preclinical studies using G6PD deficient (G6PDd) cells infected with human coronavirus (hCoV), show impaired cellular responses, viral proliferation and worsening oxidative damage. • Retrospective chart review in hospitalized patients with COVID19 pneumonia needing supplemental oxygen shows differences between the two groups (Normal and G6PDd) in hematological indices; the G6PDdgroup demonstrated prolonged PaO2/FiO2 ratio, and longer days on mechanical ventilation indicating the severity of the pneumonia.


Asunto(s)
COVID-19/complicaciones , Deficiencia de Glucosafosfato Deshidrogenasa/complicaciones , Síndrome de Dificultad Respiratoria/etiología , SARS-CoV-2 , Negro o Afroamericano , COVID-19/sangre , COVID-19/diagnóstico , Prueba de Ácido Nucleico para COVID-19 , Contraindicaciones de los Medicamentos , Cuidados Críticos , Femenino , Predisposición Genética a la Enfermedad , Deficiencia de Glucosafosfato Deshidrogenasa/sangre , Deficiencia de Glucosafosfato Deshidrogenasa/etnología , Deficiencia de Glucosafosfato Deshidrogenasa/fisiopatología , Humanos , Hidroxicloroquina/efectos adversos , Hidroxicloroquina/uso terapéutico , Masculino , Persona de Mediana Edad , Estrés Oxidativo , Respiración Artificial , Síndrome de Dificultad Respiratoria/sangre , Síndrome de Dificultad Respiratoria/terapia , Estudios Retrospectivos , SARS-CoV-2/aislamiento & purificación , Índice de Severidad de la Enfermedad , Distribución por Sexo
7.
Pol J Microbiol ; 69(4): 453-462, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33574873

RESUMEN

Stems and roots of Salacia genus plants have been used as a specific remedy for early-stage diabetes, and one of the four sulphonium sulphates, salacinol is the compound responsible for the anti-diabetic activity. Salacia is prone to microbial contamination and insect infestation; hence, methods to estimate the microbial load in such plants will enhance its nutritional value. This paper highlights the novel use of Soleris® to quantify microbes of all types, namely bacteria, yeasts, molds, and coliforms in herbal extracts. The microbial analysis results obtained with Soleris® test vial have been compared with the conventional method, and the results indicate that Soleris® is equally efficient as the conventional method and in fact displays several advantages over the traditional method. The Soleris® method is a real time monitoring system that is highly sensitive, user-friendly, and environmentally friendly since it generates very little biomedical waste and saves a large amount of time. The data presented here demonstrate that for highly contaminated samples, results are available within 24 h. For yeasts and molds, the Soleris® method produces results in 48 h, thus offering considerable time savings compared to other commonly used methods.


Asunto(s)
Bacterias/crecimiento & desarrollo , Carga Bacteriana , Contaminación de Medicamentos , Hongos/crecimiento & desarrollo , Técnicas Microbiológicas , Extractos Vegetales , Salacia/microbiología , Dióxido de Carbono/análisis , Raíces de Plantas/microbiología , Tallos de la Planta/microbiología , Plantas Medicinales/microbiología , Programas Informáticos
8.
Braz. j. microbiol ; 49(4): 848-855, Oct.-Dec. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-974300

RESUMEN

ABSTRACT We studied the role of Thermus thermophilus Recombinase A (RecA) in enhancing the PCR signals of DNA viruses such as Hepatitis B virus (HBV). The RecA gene of a thermophilic eubacterial strain, T. thermophilus, was cloned and hyperexpressed in Escherichia coli. The recombinant RecA protein was purified using a single heat treatment step without the use of any chromatography steps, and the purified protein (>95%) was found to be active. The purified RecA could enhance the polymerase chain reaction (PCR) signals of HBV and improve the detection limit of the HBV diagnosis by real time PCR. The yield of recombinant RecA was ∼35 mg/L, the highest yield reported for a recombinant RecA to date. RecA can be successfully employed to enhance detection sensitivity for the diagnosis of DNA viruses such as HBV, and this methodology could be particularly useful for clinical samples with HBV viral loads of less than 10 IU/mL, which is interesting and novel.


Asunto(s)
Proteínas Bacterianas/genética , Virus de la Hepatitis B/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Thermus thermophilus/enzimología , Clonación Molecular , Recombinasas/genética , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Expresión Génica , Virus de la Hepatitis B/genética , Reacción en Cadena de la Polimerasa/instrumentación , Thermus thermophilus/genética , Recombinasas/aislamiento & purificación , Recombinasas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo
9.
Biotechnol Rep (Amst) ; 19: e00270, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30197870

RESUMEN

Using Sso7d from Sulfolobus solfataricus as the DNA binding protein fused to Taq DNA polymerase at its amino terminus, we report the hyper-expression and a novel purification methodology of Sso7d-Taq polymerase (S-Taq) using aqueous two-phase extraction system followed by Ni-affinity chromatography. The utility of such a fusion enzyme in carrying out PCR of human genes from whole blood directly and in detecting hepatitis B virus from clinical samples is demonstrated in this article. We present data on the enhanced thermo-stability of S-Taq DNA polymerase over Taq DNA polymerase and also provide evidence of its higher stability with detergents in comparison to Taq polymerase. The purified S-Taq protein showed acceptable limits of host genomic DNA levels without the use of DNases and other DNA precipitating agents and shows promising potential for use in PCR based diagnostics, in-situ PCR's and forensic science.

10.
MethodsX ; 5: 881-889, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30151348

RESUMEN

Genomic DNA (gDNA) obtained from whole blood samples is a critical element for genomic research and clinical diagnosis. PCR efficiencies of the targeted genes like HLA-A, -B, -C, DPB1 and DRB1 using such isolated gDNAs were variable in spite of having similar amounts of gDNA taken for PCR. We addressed such PCR variabilities by normalizing the gDNA's using an internal control of human coagulation factor XIII that was found to be variable with all samples and did not correlate with the observed A260 nm readings. The PCR and Q-PCR methodologies for the human coagulation factor XIII have been optimized, and the advantages of normalizing gDNA preparations based on F13 copy numbers have been discussed. This method will serve as a suitable choice to be used in laboratories and research centres, particularly when dealing with a large number of samples for the next-generation sequencing purposes, and in forensic labs with limited sample availability.

11.
J Biomol Tech ; 29(2): 46-53, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29623006

RESUMEN

High quality and sufficient quantity of genomic DNA (gDNA) are the primary requisites of several molecular biologic applications, including clinical studies related to genetics, genomics, gene polymorphism, and DNA fingerprinting. Whole blood is the primary source of gDNA in most of the clinical investigations. Currently, commercial kits are primarily used to achieve these goals. However, the use of kits is limited by the cost and involvement of several centrifugal steps. Other methods reported are either laborious or do not produce high quality or quantity of gDNA or both. Here, we present the data on the development of a centrifugation-free, cost-effective, and user-friendly method for the isolation of human gDNA from the buffy coat of human blood that involves limited numbers of steps with about 15 min of hands-on time per sample.


Asunto(s)
ADN/aislamiento & purificación , Genoma Humano/genética , Genómica/métodos , ADN/sangre , ADN/genética , Dermatoglifia del ADN , Humanos , Polimorfismo de Nucleótido Simple/genética
12.
Braz J Microbiol ; 49(4): 848-855, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29691193

RESUMEN

We studied the role of Thermus thermophilus Recombinase A (RecA) in enhancing the PCR signals of DNA viruses such as Hepatitis B virus (HBV). The RecA gene of a thermophilic eubacterial strain, T. thermophilus, was cloned and hyperexpressed in Escherichia coli. The recombinant RecA protein was purified using a single heat treatment step without the use of any chromatography steps, and the purified protein (>95%) was found to be active. The purified RecA could enhance the polymerase chain reaction (PCR) signals of HBV and improve the detection limit of the HBV diagnosis by real time PCR. The yield of recombinant RecA was ∼35mg/L, the highest yield reported for a recombinant RecA to date. RecA can be successfully employed to enhance detection sensitivity for the diagnosis of DNA viruses such as HBV, and this methodology could be particularly useful for clinical samples with HBV viral loads of less than 10IU/mL, which is interesting and novel.


Asunto(s)
Proteínas Bacterianas/genética , Clonación Molecular , Virus de la Hepatitis B/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Recombinasas/genética , Thermus thermophilus/enzimología , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Virus de la Hepatitis B/genética , Reacción en Cadena de la Polimerasa/instrumentación , Recombinasas/aislamiento & purificación , Recombinasas/metabolismo , Thermus thermophilus/genética
13.
J Maxillofac Oral Surg ; 17(2): 254-259, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29618895

RESUMEN

INTRODUCTION: Oral submucosal fibrosis (OSMF) is a chronic debilitating fibrotic disease of the oral cavity and is a serious health hazard in south Asia and, increasingly, the rest of the world. The molecular basis behind various treatment modalities to treat OSMF still remains unclear. In this study, we have investigated the in vitro ability of the buccal mucosal cells to reduce the proliferation of the fibroblasts of the fibrotic area in co-culture of cells and also at the molecular levels to reduce the level of connective tissue growth factor (CTGF) in the OSMF fibroblasts (SMF-F). MATERIALS AND METHODS: The study compares isolation, morphological and proliferation kinetics of SMF-F and BMF cells with and without co-culturing with BMEs. In addition, we have compared the mRNA expression levels of CTGF in SMF-F co-cultured BME and non-co-cultured SMF-F cells using validated real-time quantitative PCR (RT-qPCR) method. RESULTS: The basic morphological characteristics of SMF-F were similar to BMF, but the former cells had higher proliferation rate in early passages compared to late passage state. We also observed that the CTGF expression levels in SMF-F under co-culture conditions of BME were consistently and significantly downregulated in all four different SMF-F-derived cells from four different patients. CONCLUSION: Rapid proliferation and collagen synthesis in SMF-F as against BMF cells are the factors that confirm the innate nature of fibrosis fibroblasts (SMF-F). Further, the CTGF expression level in SMF-F was significantly suppressed by BME in co-culture conditions against controls (BMF). Considered together, this suggests that the cell therapeutic candidate of BME could be used in treating OSMF.

14.
Artículo en Inglés | MEDLINE | ID: mdl-26908378

RESUMEN

Left ventricular non-compaction is a recently recognized, rare form of cardiomyopathy. It is based on the arrest of endomyocardial morphogenesis during embryogenesis. It was first described in 1984 by Engberding who described it as isolated 'sinusoids' within the LV. Right now its prevalence is estimated at 0.014 to 1.3 and 3-4% in heart failure patients. Its clinical manifestations are highly variable, ranging from no symptoms to disabling congestive heart failure, arrhythmias, and systemic thromboemboli. Doppler Echocardiogram is considered the diagnostic procedure of choice and treatment is symptomatic management of its symptoms and complications.

15.
Artículo en Inglés | MEDLINE | ID: mdl-26653697

RESUMEN

We discuss a unique case of a 52-year-old man with no history of intravenous drug use or dental procedures who presented with neck pain, 2 weeks of fevers, chills, night sweats, cough, and dyspnea found to have isolated pulmonic valve (PV) endocarditis. The patient did not have an associated murmur, which is commonly seen in right-sided infectious endocarditis. A transthoracic echocardiogram showed a thickened PV leaflet, with subsequent transesophageal echocardiogram showing a PV mass. Speciation of blood cultures revealed Streptococcus oralis. In right-sided infective endocarditis, usually the tricuspid valve is involved; however, in our case the tricuspid valve was free of any mass or vegetation. The patient did meet Duke criteria and was thus started on long-term intravenous antibiotics for infectious endocarditis. The patient's symptoms quickly improved with antibiotics. A careful history and evaluating the patient's risk factors are key in earlier detection of infective endocarditis (IE). Because of early detection and a high index of suspicion, the patient had no further complications and did not require any surgery. In conclusion, clinical suspicion of right-sided IE should be high in patients who present with persistent fevers and pulmonary symptoms in order to reduce the risk of complications, and to improve outcomes.

16.
Microbiology (Reading) ; 160(Pt 10): 2157-2169, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25023246

RESUMEN

P128 is an anti-staphylococcal protein consisting of the Staphylococcus aureus phage-K-derived tail-associated muralytic enzyme (TAME) catalytic domain (Lys16) fused with the cell-wall-binding SH3b domain of lysostaphin. In order to understand the mechanism of action and emergence of resistance to P128, we isolated mutants of Staphylococcus spp., including meticillin-resistant Staphylococcus aureus (MRSA), resistant to P128. In addition to P128, the mutants also showed resistance to Lys16, the catalytic domain of P128. The mutants showed loss of fitness as shown by reduced rate of growth in vitro. One of the mutants tested was found to show reduced virulence in animal models of S. aureus septicaemia suggesting loss of fitness in vivo as well. Analysis of the antibiotic sensitivity pattern showed that the mutants derived from MRSA strains had become sensitive to meticillin and other ß-lactams. Interestingly, the mutant cells were resistant to the lytic action of phage K, although the phage was able to adsorb to these cells. Sequencing of the femA gene of three P128-resistant mutants showed either a truncation or deletion in femA, suggesting that improper cross-bridge formation in S. aureus could be causing resistance to P128. Using glutathione S-transferase (GST) fusion peptides as substrates it was found that both P128 and Lys16 were capable of cleaving a pentaglycine sequence, suggesting that P128 might be killing S. aureus by cleaving the pentaglycine cross-bridge of peptidoglycan. Moreover, peptides corresponding to the reported cross-bridge of Staphylococcus haemolyticus (GGSGG, AGSGG), which were not cleaved by lysostaphin, were cleaved efficiently by P128. This was also reflected in high sensitivity of S. haemolyticus to P128. This showed that in spite of sharing a common mechanism of action with lysostaphin, P128 has unique properties, which allow it to act on certain lysostaphin-resistant Staphylococcus strains.


Asunto(s)
Pared Celular/metabolismo , Péptido Hidrolasas/metabolismo , Peptidoglicano/metabolismo , Fagos de Staphylococcus/enzimología , Staphylococcus/efectos de los fármacos , Animales , Antibacterianos/aislamiento & purificación , Antibacterianos/metabolismo , Modelos Animales de Enfermedad , Farmacorresistencia Bacteriana , Péptido Hidrolasas/genética , Péptido Hidrolasas/aislamiento & purificación , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Sepsis/microbiología , Staphylococcus/crecimiento & desarrollo , Staphylococcus/aislamiento & purificación , Virulencia
17.
Bacteriophage ; 3(3): e26564, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24251076

RESUMEN

P128 is a chimeric anti-staphylococcal protein having a catalytic domain from a Staphylococcus bacteriophage K tail associated structural protein and a cell wall targeting domain from the Staphylococcus bacteriocin-lysostaphin. In this study, we disclose additional properties of P128 and compared the same with lysostaphin. While lysostaphin was found to get inactivated by heat and was inactive on its parent strain S. simulans biovar staphylolyticus, P128 was thermostable and was lytic towards S. simulans biovar staphylolyticus demonstrating a difference in their mechanism of action. Selected mutation studies of the catalytic domain of P128 showed that arginine and cysteine, at 40th and 76th positions respectively, are critical for the staphylolytic activity of P128, although these amino acids are not conserved residues. In comparison to native P128, only the R40S mutant (P301) was catalytically active on zymogram gel and had a similar secondary structure, as assessed by circular dichroism analysis and in silico modeling with similar cell binding properties. Mutation of the arginine residue at 40th position of the P128 molecule caused dramatic reduction in the Vmax (∆OD600 [mg/min]) value (nearly 270 fold) and the recombinant lysostaphin also showed lesser Vmax value (nearly 1.5 fold) in comparison to the unmodified P128 protein. The kinetic parameters such as apparent Km (KmAPP) and apparent Kcat (KcatAPP) of the native P128 protein also showed significant differences in comparison to the values observed for P301 and lysostaphin.

18.
Vet Res Commun ; 37(3): 217-28, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23661290

RESUMEN

In this study, we demonstrate the antibacterial activity of P128 on Staphylococcus isolates responsible for canine pyoderma. Eighty seven swabs were collected from dogs suffering from pyoderma and subjected to antibiotic sensitivity test and 46 Staphylococcus strains were isolated and characterized. In-vitro antimicrobial susceptibility testing with P128 was done by Minimum Inhibitory Concentration (MIC) method as per CLSI guidelines. All the Staphylococci isolated from the dogs with pyoderma, although showed resistance to various antibiotics tested, were lysed by P128. Clinical efficacy of P128 was examined in 17 dogs with pyoderma by application of the P128 hydrogel twice daily for 8 days and the results indicated complete healing of all the lesions of all the dogs under treatment. Under the conditions of this study, P128 was found to be a potent convenient proteinaceous drug for the treatment of staphylococcal pyoderma in dogs.


Asunto(s)
Enfermedades de los Perros/tratamiento farmacológico , Piodermia/veterinaria , Proteínas Recombinantes de Fusión/uso terapéutico , Staphylococcus/efectos de los fármacos , Animales , Enfermedades de los Perros/microbiología , Perros , Femenino , Masculino , Pruebas de Sensibilidad Microbiana/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo de Longitud del Fragmento de Restricción , Piodermia/tratamiento farmacológico , Piodermia/microbiología , Proteínas Recombinantes de Fusión/administración & dosificación , Staphylococcus/clasificación , Staphylococcus/genética , Staphylococcus/aislamiento & purificación
19.
Virus Res ; 169(1): 182-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22917718

RESUMEN

We demonstrate that the prophage status of bacteria plays a critical role in achieving homogenous population of a phage preparation. When a lytic Staphylococcus bacteriophage 44AHJD was propagated in a Staphylococcus clinical isolate, the enriched phage showed 44AHJD phage virions along with the released prophages from the baiting host. The released prophage was identified as a siphophage by transmission electron microscopy. To obtain a phage preparation free of prophages, when we carried out multiplication of the 44AHJD phage in a prophage free Staphyloccoccus aureus host namely RN4220, we were surprised not to see any phage plaques in spite of the phage exhibiting >99.9% adsorption to such cells. Since RN4220 host is devoid of restriction modification system and prophages, we hypothesized that in spite of successful infection and multiplication, the phage virions might have failed to show plaques due to its insignificant release from the cell possibly due to insufficient endolysin expressed from phage virions during phage development and assembly. Our hypothesis was confirmed when we observed plaques of 44AHJD phage in RN4220 cells where additional phage endolysin protein was supplemented via a plasmid. Endolysin protein from various types of Staphylococcus phages showed plaques of 44AHJD in RN4220 cells confirming our hypothesis. Also, we demonstrate for the first time that propagation of 44AHJD phage with endolysin supplementation in prophage free RN4220 host yields pure phage preparation.


Asunto(s)
Bacteriófagos/aislamiento & purificación , Staphylococcus aureus/virología , Animales , Bacteriólisis , Bacteriófagos/genética , Endopeptidasas/genética , Endopeptidasas/metabolismo , Humanos , Microscopía Electrónica de Transmisión , Profagos/genética , Profagos/aislamiento & purificación , Profagos/ultraestructura , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificación , Virión/ultraestructura
20.
Med Dosim ; 37(1): 53-60, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21741819

RESUMEN

A commercial 2D array seven29 detector has been characterized and its performance has been evaluated. 2D array ionization chamber equipped with 729 ionization chambers uniformly arranged in a 27 × 27 matrix with an active area of 27 × 27 cm² was used for the study. An octagon-shaped phantom (Octavius Phantom) with a central cavity is used to insert the 2D ion chamber array. All measurements were done with a linear accelerator. The detector dose linearity, reproducibility, output factors, dose rate, source to surface distance (SSD), and directional dependency has been studied. The performance of the 2D array, when measuring clinical dose maps, was also investigated. For pretreatment quality assurance, 10 different RapidArc plans conforming to the clinical standards were selected. The 2D array demonstrates an excellent short-term output reproducibility. The long-term reproducibility was found to be within ±1% over a period of 5 months. Output factor measurements for the central chamber of the array showed no considerable deviation from ion chamber measurements. We found that the 2D array exhibits directional dependency for static fields. Measurement of beam profiles and wedge-modulated fields with the 2D array matched very well with the ion chamber measurements in the water phantom. The study shows that 2D array seven29 is a reliable and accurate dosimeter and a useful tool for quality assurance. The combination of the 2D array with the Octavius phantom proved to be a fast and reliable method for pretreatment verification of rotational treatments.


Asunto(s)
Garantía de la Calidad de Atención de Salud/normas , Radiometría/instrumentación , Radiometría/métodos , Radioterapia Conformacional/instrumentación , India , Fantasmas de Imagen/normas , Dosificación Radioterapéutica , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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