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1.
Genet Mol Res ; 15(1)2016 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-26909942

RESUMEN

Diabetic nephropathy is the leading cause of end-stage kidney disease in the world. Many single nucleotide polymorphisms (SNPs) have been associated with diabetic nephropathy. SNPs at the 4.1 protein ezrin, radixin, moesin domain 3 (FRMD3) and cysteinyl t-RNA synthetase (CARS) genes have a well-established relationship with diabetic nephropathy. However, this association has not been evaluated in a Kuwaiti population. DNA was extracted from blood samples obtained from patients with diabetic nephropathy (N = 38); the genes of interest were amplified, and the SNPs were genotypes. Diabetics without nephropathy (N = 64) were used as controls. The risk (G and C) and non-risk (C and T) allele frequencies of the SNPs at the rs1888747 and rs739401 loci of FRMD3 and CARS, respectively, did not differ significantly between the diabetics with (case) and without (control) nephropathy (P > 0.05). These findings suggest that the molecular mechanisms involved in diabetic nephropathy may be different in a Kuwaiti population, compared to other populations (such as Japanese and Caucasian Europeans). The discrepancies observed in our study could also be attributed to the smaller sample size analyzed in this study. Therefore, further analyses with larger samples are required to identify the susceptibility genes in a Middle-Eastern population.


Asunto(s)
Aminoacil-ARNt Sintetasas/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Nefropatías Diabéticas/genética , Polimorfismo de Nucleótido Simple , Insuficiencia Renal Crónica/genética , Proteínas Supresoras de Tumor/genética , Alelos , Proteínas del Citoesqueleto/genética , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 2/patología , Nefropatías Diabéticas/patología , Expresión Génica , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Kuwait , Proteínas de la Membrana/genética , Insuficiencia Renal Crónica/patología
2.
Clin Microbiol Infect ; 27(4): 624-629, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32505583

RESUMEN

OBJECTIVES: Chronic infections by enteric parasites including protist and helminthic species produce long-term sequelae on the health status of infected children. This study assesses potential associations linked with enteric parasite infections in symptomatic and asymptomatic children in Zambézia province, Mozambique. METHODS: In this prospective cross-sectional study, stool samples and epidemiological questionnaires on demographics and risk associations were collected from symptomatic children (n = 286) from clinical settings and asymptomatic (n = 807) children from 17 schools and creches aged 3‒14 years. We detected enteric parasites using PCR-based methods. We calculated prevalence (adjusted for age, sex, house construction, drinking water, and latrine use) and odds ratios (ORs) for risk associations with logistic regression, after adjusting for district, neighbourhood and symptoms. RESULTS: Numbers and adjusted prevalence (95% confidence intervals in parentheses) for the symptomatic and asymptomatic populations were Giardia duodenalis 120, 52% (22-82), 339, 42% (25-59); followed by Strongyloides stercoralis 52, 14% (9‒20), 180, 20% (15-25). Risk associations for G. duodenalis included drinking untreated river/spring water, OR 2.91 (1.80-4.70); contact with ducks, OR 14.96 (2.93‒76.31); dogs, OR 1.92 (1.04-3.52); cats, OR 1.73 (1.16-2.59), and a relative with diarrhoea, OR 2.59 (1.54‒4.37). Risk associations for S. stercoralis included having no latrine, OR 2.41 (1.44-4.02); drinking well water, OR 1.82 (1.02-3.25), and increasing age, OR 1.11 (1.04-1.20). CONCLUSIONS: We found a high prevalence of intestinal parasites regardless of the children's symptoms. Drinking well or river water, domestic animals, and latrine absence were contributing factors of human infections.


Asunto(s)
Helmintiasis/epidemiología , Helmintiasis/parasitología , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/patología , Adolescente , Niño , Preescolar , Coinfección , Femenino , Humanos , Masculino , Mozambique/epidemiología , Factores de Riesgo
3.
Diabetologia ; 52(1): 160-8, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18985316

RESUMEN

AIMS/HYPOTHESIS: Elevated anti-angiogenic factors such as soluble fms-like tyrosine kinase 1 (sFlt1), a soluble form of vascular endothelial growth factor receptor, and endoglin, a co-receptor for TGFbeta1, confer high risk of pre-eclampsia in healthy pregnant women. In this multicentre prospective study, we determined levels of these and related factors in pregnant women with type 1 diabetes, a condition associated with a fourfold increase in pre-eclampsia. METHODS: Maternal serum sFlt1, endoglin, placental growth factor (PlGF) and pigment epithelial derived factor were measured in 151 type 1 diabetic and 24 healthy non-diabetic women at each trimester and at term. RESULTS: Approximately 22% of the diabetic women developed pre-eclampsia, primarily after their third trimester visit. In women with pre-eclampsia (diabetic pre-eclampsia, n = 26) vs those without hypertensive complications (diabetic normotensive, n = 95), significant changes in angiogenic factors were observed, predominantly in the early third trimester and prior to clinical manifestation of pre-eclampsia. Serum sFlt1 levels were increased approximately twofold in type 1 diabetic pre-eclampsia vs type 1 diabetic normotensive women at the third trimester visit (p < 0.05) and the normal rise of PlGF during pregnancy was blunted (p < 0.05). Among type 1 diabetic women, third trimester sFlt1 and PlGF were inversely related (r(2) = 42%, p < 0.0001). Endoglin levels were increased significantly in the diabetic group as a whole vs the non-diabetic group (p < 0.0001). CONCLUSIONS/INTERPRETATION: Higher sFlt1 levels, a blunted PlGF rise and an elevated sFlt1/PlGF ratio are predictive of pre-eclampsia in pregnant women with type 1 diabetes. Elevated endoglin levels in women with type 1 diabetes may confer a predisposition to pre-eclampsia and may contribute to the high incidence of pre-eclampsia in this patient group.


Asunto(s)
Inhibidores de la Angiogénesis/sangre , Diabetes Mellitus Tipo 1/complicaciones , Preeclampsia/sangre , Adulto , Antígenos CD/sangre , Diabetes Mellitus Tipo 1/sangre , Endoglina , Proteínas del Ojo/sangre , Femenino , Hemoglobina Glucada/análisis , Hormona del Crecimiento/sangre , Humanos , Proteínas de la Membrana/sangre , Factores de Crecimiento Nervioso/sangre , Embarazo , Complicaciones del Embarazo/sangre , Receptores de Superficie Celular/sangre , Serpinas/sangre , Receptor 1 de Factores de Crecimiento Endotelial Vascular/sangre
4.
J Chemother ; 19(3): 271-6, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17594921

RESUMEN

Extended-spectrum beta-lactamases (ESBLs) are a major problem in Kuwait and an accurate method for their detection is essential. This study was designed to evaluate the efficacy of the commercial system (Vitek 2) to identify ESBLs in clinical isolates of Escherichia coli and relate this to their identification by agar dilution methods for use in a diagnostic laboratory. The presence of the major ESBLs parental enzyme groups was confirmed by PCR and the similarity of the strains was determined by pulsed field gel electrophoresis (PFGE) on DNA, cleaved using XbaI endonuclease, to identify clonal spread.Seventy-one separate E. coli isolates from 65 patients were tested. Sixty-two isolates were from 56 patients from the Al-Amiri Hospital and nine isolates from neonates from Farwania Hospital. The isolates were screened for ESBL activity by the Vitek 2 system. Isolates showing positive results were further tested with Etest ESBL strips and by the disc approximation methods. All the isolates were flagged as ESBL-positive by the Vitek 2 advanced expert system (AES). Isolates from all the 65 patients were detected as ESBL positive by the Etest, only if both ESBL strips were used. The double disc approximation test using five different antibiotics could detect ESBL presence in isolates from only 46 patients. In this test, the synergy with cefepime was the most sensitive in ESBL detection, showing their presence in 41 isolates. PCR with primers for bla(TEM) and bla(SHV) demonstrated that one or both of these enzymes in all isolates. PFGE revealed that many different clones were present amongst the isolates. The epidemiology of ESBL E. coli in Kuwait is complex. Many distinct strains are already present in the population, as shown by the results of PFGE. Several testing methods may be required to detect all strains harboring ESBLs.


Asunto(s)
Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Resistencia betalactámica , beta-Lactamasas/metabolismo , Técnicas Bacteriológicas , Brotes de Enfermedades , Electroforesis en Gel de Campo Pulsado , Escherichia coli/aislamiento & purificación , Hospitales , Humanos , Kuwait/epidemiología , Reacción en Cadena de la Polimerasa
5.
J Med Microbiol ; 55(Pt 4): 417-421, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16533989

RESUMEN

Two hundred and fifty-one unique patient isolates of Klebsiella pneumoniae (123), Escherichia coli (114), Klebsiella oxytoca (7), Enterobacter cloacae (5) and Citrobacter freundii (2), flagged as extended-spectrum beta-lactamase (ESBL) positive by the Vitek system (GNS-526 card), were collected. These strains were isolated from a variety of clinical specimens submitted to the clinical bacteriology laboratories of the Royal Infirmary of Edinburgh (RIE), Edinburgh, UK (and associated GP practices), Hairmyers Hospital, Glasgow, UK, and the Amiri and Farwania Hospitals, Kuwait. Of the 101 RIE strains tested, 15 E. coli strains were found to be ESBL negative by Etest ESBL strips. On retesting the 15 E. coli strains with the Vitek GNS-532 card, 14 were found to be ESBL negative, despite being originally flagged as ESBL positive. The remaining 236 ESBL-producing strains were also subjected to the double disc-diffusion (DDD) technique for the detection of ESBLs. Of these, two were false negatives by Etest ESBL test strips (using both cefotaxime and ceftazidime strips), and 38 were false negatives by the DDD method. The Etest false-negative ESBL-producing strains of K. pneumoniae were positive by DDD. Technically, the Vitek method was the least demanding method to perform, as it was an integral part of the routine susceptibility test card. Etest strips were reliable, but were the most expensive of all the techniques used. The DDD test, while relatively inexpensive, was technically subjective, and in our hands, seven of the ESBL-positive strains that were confirmed by the other two techniques were not detected. Despite the false-positive ESBL-producing E. coli strains, the Vitek susceptibility card with its integral ESBL test offers the clinical laboratory a valuable and quick option to screen for ESBL-producing Klebsiella spp. and E. coli as part of the routine laboratory methodology.


Asunto(s)
Técnicas Bacteriológicas/métodos , Farmacorresistencia Bacteriana , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/enzimología , beta-Lactamasas/metabolismo , Antibacterianos/farmacología , Automatización , Enterobacteriaceae/clasificación , Infecciones por Enterobacteriaceae/microbiología , Humanos , Kuwait , Reino Unido , beta-Lactamasas/genética
6.
Int J Antimicrob Agents ; 27(1): 73-6, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16321509

RESUMEN

The objective of this study was to examine the epidemiology of ciprofloxacin-resistant, extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae strains. Sixty-nine unique patient isolates of K. pneumoniae isolated from a variety of clinical specimens submitted to the clinical bacteriology laboratories of The Royal Infirmary of Edinburgh and associated General Practices were identified and susceptibility testing was performed with the Vitek system. Strains flagged as ESBL-positive by the Vitek system were subjected to isoelectric focusing. The results suggested that all 69 isolates harboured at least one ESBL, which was later confirmed by polymerase chain reaction (PCR) with bla(TEM) and/or bla(SHV) primers. The purified PCR product was subjected to automated sequencing and the results were compared with the BLAST online search engine. Of the 69 isolates, 32 (46.4%) were found to be resistant to ciprofloxacin, 11 (15.9%) were intermediate and 26 (37.7%) were sensitive. To investigate the epidemiological relationship between the ciprofloxacin-resistant ESBL-positive strains, pulsed-field gel electrophoresis (PFGE) was performed. Rapidest software was used to calculate the genetic distance by the Nei distance method. PFGE analysis indicated that the clinical isolates belonged to four distinct genotype clusters (Groups A, B, C and D); each group or cluster was homogeneous or compact with respect to certain characteristics. Group A consisted of 25 isolates, group B of 3 isolates and Groups C and D of 2 isolates each. These results indicate that the spread of resistance is largely as a result of the dissemination of a single clonal strain. PCR was used to amplify the gyrA and parC genes from genomic DNA of the ciprofloxacin-resistant isolates. The amplified product was sent for analysis by automated DNA sequencing and the resulting DNA sequences were compared with the gyrA gene of K. pneumoniae. The sequencing results demonstrated that alteration of the GyrA subunit of DNA gyrase at amino acid 83 and/or amino acid 87 plays a central role in conferring high-level quinolone resistance in K. pneumoniae possessing ESBLs.


Asunto(s)
Antiinfecciosos/farmacología , Ciprofloxacina/farmacología , Farmacorresistencia Bacteriana/genética , Klebsiella pneumoniae/genética , Familia de Multigenes , Proteínas de la Membrana Bacteriana Externa/genética , Girasa de ADN/genética , Topoisomerasa de ADN IV/genética , Electroforesis en Gel de Campo Pulsado , Humanos , Focalización Isoeléctrica , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Escocia/epidemiología , Resistencia betalactámica/genética
7.
Biochim Biophys Acta ; 1302(3): 224-30, 1996 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-8765143

RESUMEN

A full-length recombinant human apolipoprotein C-II (ApoC-II) has been successfully expressed in Escherichia coli using the T7 expression system. The recombinant ApoC-II. which was expressed intracellularly in the inclusion bodies, was solubilized with 8 M urea and purified using Sephadex G-75 gel permeation chromatography. Four liters of the bacterial culture yielded 16-20 mg of purified recombinant ApoC-II. Sequencing and mass spectrometric analyses indicated that the isolated recombinant ApoC-II contained predominantly (64%) the native form with threonine as the N-terminus, but also contained a minor (36%) molecular form of ApoC-II with an additional methionine at the N-terminus (Met-ApoC-II). Analysis of the recombinant ApoC-II by tryptic digestion and high performance liquid chromatography-electrospray mass spectrometry provides additional conclusive evidence that, with the exception of the N-terminus of Met-ApoC-II, the expressed ApoC-II has the expected peptide sequence. However, this extra N-terminal methionine residue can be excised by further in vitro treatment with methionine aminopeptidase. The purified recombinant ApoC-II was found to be competent in the activation of bovine milk lipoprotein lipase. Thus, the recombinant ApoC-II prepared from E. coli may have a pharmacological application for the treatment of patients with genetic hypertriglyceridemia caused by ApoC-II deficiency.


Asunto(s)
Apolipoproteínas C/aislamiento & purificación , Escherichia coli/genética , Secuencia de Aminoácidos , Aminopeptidasas/metabolismo , Animales , Apolipoproteína C-II , Apolipoproteínas C/química , Apolipoproteínas C/genética , Secuencia de Bases , Bovinos , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Activación Enzimática/efectos de los fármacos , Humanos , Lipoproteína Lipasa/metabolismo , Espectrometría de Masas , Metionil Aminopeptidasas , Leche/enzimología , Datos de Secuencia Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/farmacología
8.
J Thromb Haemost ; 3(7): 1467-71, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15978104

RESUMEN

BACKGROUND: Venous thromboembolism (VTE) occurs due to a number of hereditary and acquired disorders of hemostasis. A recently identified polymorphism in factor V gene (A4070G; named HR2) has been reported to be a possible risk factor for the development of VTE, with a high prevalence of 9.5%-15.2% in patients of different ethnic groups in different parts of the world. However, the prevalence of HR2 has not yet been tested in VTE patients of Arab ethnicity. OBJECTIVES: To study the prevalence and possible risk of HR2 haplotype in Arabs. PATIENTS/METHODS: Exactly 188 VTE patients and 100 healthy subjects, all being of Arab ethnicity, were examined for HR2 using Polymerase chain reaction, restriction fragment length polymorphism and agarose gel electrophoresis. RESULTS: Data showed that 31 patients and seven healthy subjects had HR2 haplotype, with a prevalence of 16.5% and 7%, respectively. Furthermore, 43 patients (22.9%) had more than one risk factor for VTE. CONCLUSIONS: The prevalence of HR2 in Arabs is quite high, with a 2.62-fold greater risk of developing VTE. Moreover, coexistence of two or more genetic/acquired defects of VTE is quite common in Arab patients.


Asunto(s)
Factor V/genética , Polimorfismo Genético , Trombosis de la Vena/epidemiología , Trombosis de la Vena/genética , Árabes , Estudios de Casos y Controles , Electroforesis en Gel de Agar , Femenino , Haplotipos , Heterocigoto , Humanos , Kuwait , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Riesgo , Factores de Riesgo
9.
Curr Pharm Des ; 11(27): 3531-43, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16248806

RESUMEN

To develop an effective pharmaceutical treatment for a disease, we need to fully understand the biological behavior of that disease, especially when dealing with cancer. The current available treatment for cancer may help in lessening the burden of the disease or, on certain occasions, in increasing the survival of the patient. However, a total eradication of cancer remains the researchers' hope. Some of the discoveries in the field of medicine relied on observations of natural events. Among these events is the spontaneous regression of cancer. It has been argued that such regression could be immunologically-mediated, but no direct evidence has been shown to support such an argument. We, hereby, provide compelling evidence that spontaneous cancer regression in humans is immunologically-mediated, hoping that the results from this study would stimulate the pharmaceutical industry to focus more on cancer vaccine immunotherapy. Our results showed that patients with >3 primary melanomas (very rare group among cancer patients) develop significant histopathological spontaneous regression of further melanomas that they could acquire during their life (P=0.0080) as compared to patients with single primary melanoma where the phenomenon of spontaneous regression is absent or minimal. It seems that such regression resulted from the repeated exposure to the tumor which mimics a self-immunization process. Analysis of the regressing tumors revealed heavy infiltration by T lymphocytes as compared to non-regressing tumors (P<0.0001), the predominant of which were T cytotoxic rather than T helper. Mature dendritic cells were also found in significant number (P<0.0001) in the regressing tumors as compared to the non regressing ones, which demonstrate an active involvement of the different arms of the immune system in the multiple primary melanoma patients in the process of tumor regression. Also, MHC expression was significantly higher in the regressing versus the non-regressing tumors (P <0.0001), which reflects a proper tumor antigen expression. Associated with tumor regression was also loss of the melanoma common tumor antigen Melan A/ MART-1 in the multiple primary melanoma patients as compared to the single primary ones (P=0.0041). Furthermore, loss of Melan A/ MART-1 in the regressing tumors significantly correlated with the presence of Melan A/ MART-1-specific CTLs in the peripheral blood of these patients (P=0.03), which adds to the evidence that the phenomenon of regression seen in these patients was immunologically-mediated and tumor-specific. Such correlation was also seen in another rare group of melanoma patients, namely those with occult primary melanoma. The lesson that we could learn from nature in this study is that inducing cancer regression using the different arms of the immune system is possible. Also, developing a novel cancer vaccine is not out of reach.


Asunto(s)
Vacunas contra el Cáncer/uso terapéutico , Industria Farmacéutica/tendencias , Motivación , Regresión Neoplásica Espontánea/inmunología , Observación/métodos , Antígenos de Neoplasias , Vacunas contra el Cáncer/inmunología , Pruebas Inmunológicas de Citotoxicidad/métodos , Industria Farmacéutica/economía , Industria Farmacéutica/métodos , Humanos , Antígeno MART-1 , Melanoma/inmunología , Melanoma/patología , Melanoma/terapia , Proteínas de Neoplasias/análisis , Proteínas de Neoplasias/inmunología , Regresión Neoplásica Espontánea/genética , Regresión Neoplásica Espontánea/patología , Neoplasias Primarias Desconocidas/inmunología , Linfocitos T Citotóxicos/inmunología , Tecnología Farmacéutica/métodos , Tecnología Farmacéutica/tendencias
10.
Eur J Paediatr Dent ; 6(2): 97-104, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16004539

RESUMEN

AIM: This study was designed to find the most reliable method of measurement of mesiodistal tooth diameter. METHODS: Measurements were made of all erupted permanent teeth of 14 orthodontic study casts. These measurements were made directly by using A) a digital calliper, B) measuring photocopies of casts with a calliper, C) a Magiscan Image Analysis using a photocopy of the casts. Measurements derived from the two methods were compared by statistical analysis. RESULTS: These showed that the electronic digital calliper was the most reliable method of measuring mesiodistal tooth diameter using dental study casts. The measurement of photocopies was unreliable and the image analysis method had a too high error factor.


Asunto(s)
Instrumentos Dentales , Diente/anatomía & histología , Procesos de Copia , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Dentales , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Mantenimiento del Espacio en Ortodoncia
11.
Struct Dyn ; 2(4): 041601, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26798800

RESUMEN

Single-particle structure recovery without crystals or radiation damage is a revolutionary possibility offered by X-ray free-electron lasers, but it involves formidable experimental and data-analytical challenges. Many of these difficulties were encountered during the development of cryogenic electron microscopy of biological systems. Electron microscopy of biological entities has now reached a spatial resolution of about 0.3 nm, with a rapidly emerging capability to map discrete and continuous conformational changes and the energy landscapes of biomolecular machines. Nonetheless, single-particle imaging by X-ray free-electron lasers remains important for a range of applications, including the study of large "electron-opaque" objects and time-resolved examination of key biological processes at physiological temperatures. After summarizing the state of the art in the study of structure and conformations by cryogenic electron microscopy, we identify the primary opportunities and challenges facing X-ray-based single-particle approaches, and possible means for circumventing them.

12.
Int J Antimicrob Agents ; 13(4): 273-9, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10755241

RESUMEN

Dot blot hybridization and the polymerase chain reaction (PCR) were used to study aminoglycoside-modifying enzymes in aminoglycoside-resistant staphylococci isolated in hospitals in Kuwait. DNA encoding the acetyltransferase (AAC) (6')-phosphotransferase (APH) (2"), nucleotidyltransferase (ANT) (4') and APH (3') enzymes were detected in Staphylococcus aureus and coagulase negative staphylococci. ANT (4') was the most common enzyme detected. The majority of isolates contained genes for all three modifying enzymes, AAC (6')-APH (2"), ANT (4') and APH (3'); only few isolates carried genes for a single modifying enzyme. Genes encoding the AAC (6')-APH (2") were detected in all except two gentamicin-resistant isolates. In these isolates the genes for the AAC (6')-APH (2") enzyme could not be detected by PCR and dot blot hybridization. Whereas antibiotic resistance testing could be used to predict the presence of the AAC (6')-APH (2") enzyme it was not useful in predicting the presence of the ANT (4') or APH (3') enzymes in gentamicin-resistant isolates. Results obtained with dot blot hybridization were comparable to those obtained with PCR. However, PCR was fast and results were obtained within the same day. Therefore PCR would be preferred for the detection and confirmation of the presence of aminoglycoside-modifying enzymes in clinical microbiology laboratories.


Asunto(s)
Antibacterianos/metabolismo , Infección Hospitalaria/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus/genética , Acetiltransferasas/genética , Aminoglicósidos , Farmacorresistencia Microbiana , Genotipo , Humanos , Kanamicina Quinasa/genética , Pruebas de Sensibilidad Microbiana , Hibridación de Ácido Nucleico , Nucleotidiltransferasas/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Reacción en Cadena de la Polimerasa , Staphylococcus/enzimología , Staphylococcus/aislamiento & purificación
13.
Community Dent Health ; 12(1): 42-7, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7697564

RESUMEN

A study was carried out in Kuwait, a country with low levels of fluoride in the water supplies, to determine the prevalence and extent of caries in early childhood, and enquire into associated factors. Mothers of pre-schoolchildren were interviewed, and their children aged 18 to 48 months received a dental examination. Of the 227 children examined, 107 (47 per cent) were caries free, and 41 (18%) had five or more dmf teeth. 'Nursing caries', affecting at least two maxillary incisors, was seen in 19 per cent of the sample. Breast fed children were significantly more likely to be caries free than those who were bottle fed from birth, although 'nursing caries' was positively associated with the practice of breast feeding at night 'at will' after 6 months of age (P < 0.01). Bottle fed children were more likely to develop caries, including 'nursing caries', particularly when the practice was continued to an older age. It was concluded that 'nursing caries' constitutes a significant dental health problem in Kuwait.


Asunto(s)
Alimentación con Biberón/efectos adversos , Caries Dental/epidemiología , Lactancia Materna , Distribución de Chi-Cuadrado , Preescolar , Índice CPO , Caries Dental/etiología , Femenino , Fluoruración , Humanos , Lactante , Alimentos Infantiles/efectos adversos , Kuwait/epidemiología , Masculino , Factores Sexuales , Estadísticas no Paramétricas , Conducta en la Lactancia , Encuestas y Cuestionarios , Erupción Dental
14.
Philos Trans R Soc Lond B Biol Sci ; 369(1647): 20130326, 2014 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-24914154

RESUMEN

The advent of the X-ray free-electron laser (XFEL) has made it possible to record diffraction snapshots of biological entities injected into the X-ray beam before the onset of radiation damage. Algorithmic means must then be used to determine the snapshot orientations and thence the three-dimensional structure of the object. Existing Bayesian approaches are limited in reconstruction resolution typically to 1/10 of the object diameter, with the computational expense increasing as the eighth power of the ratio of diameter to resolution. We present an approach capable of exploiting object symmetries to recover three-dimensional structure to high resolution, and thus reconstruct the structure of the satellite tobacco necrosis virus to atomic level. Our approach offers the highest reconstruction resolution for XFEL snapshots to date and provides a potentially powerful alternative route for analysis of data from crystalline and nano-crystalline objects.


Asunto(s)
Electrones , Imagenología Tridimensional/métodos , Rayos Láser , Tombusviridae/ultraestructura , Difracción de Rayos X/métodos , Modelos Teóricos
15.
J Clin Pathol ; 63(1): 83-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19889623

RESUMEN

BACKGROUND: Enteric fever due to Salmonella enterica is a major health problem, and fluoroquinolones such as ciprofloxacin are mostly the antibiotic of choice for treatment. Resistance to ciprofloxacin has been noticed to increase due to the emergence of new mutations in the bacterial DNA. AIMS: To explore the fluoroquinolone resistance and molecular characterisation of reduced quinolone susceptibility in S typhi and S paratyphi A in Kuwait. METHODS: 136 clinical isolates of S typhi and 40 of S paratyphi A were collected over five years. The antimicrobial susceptibility was studied by various methods. DNA sequencing of gyrA, gyrB, parC and parE genes was performed in 31 isolates. RESULTS: There was a substantial difference in MIC range between the two serotypes, with the most common MIC for S typhi being 0.25 mg/l and for S paratyphi A being 1 mg/l. The proportion of nalidixic acid resistant strains increased gradually over the years. These strains had a significantly higher range of MIC of ciprofloxacin (0.023 mg/l to 1.0 mg/l) compared to the nalidixic acid sensitive strains (0.0016 mg/l to 0.125 mg/l). DNA sequencing of gyrA gene showed the presence of three different point mutations: Ser83-->Phe in 17 strains, Ser83-->Leu in 3 strains and Asp87-->Asn in 6 strains. No mutations in the other genes were found. CONCLUSIONS: It is very important to keep searching for new mutations and continuously monitor drug resistance in different parts of the world in order to efficiently manage cases with enteric fever.


Asunto(s)
Girasa de ADN/genética , Fluoroquinolonas/farmacología , Mutación Puntual , Salmonella paratyphi A/genética , Salmonella typhi/genética , Antibacterianos/farmacología , Análisis Mutacional de ADN/métodos , ADN Bacteriano/genética , Farmacorresistencia Bacteriana/genética , Genes Bacterianos , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Reacción en Cadena de la Polimerasa/métodos , Salmonella paratyphi A/efectos de los fármacos , Salmonella typhi/efectos de los fármacos , Fiebre Tifoidea/microbiología
16.
J Chemother ; 22(5): 335-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21123157

RESUMEN

Patients infected with bacteria producing extendedspectrum beta-lactamases (ESBL) are at higher risk of mortality and morbidity. Several mutations in genes encoding SHV, tem and CTX-M beta-lactamases have been associated with ESBL activity. This paper describes a new SHV mutation in ESBL-producing strains of Klebsiella pneumoniae isolated in Kuwait. The study included 13 K. penumoniae strains isolated from patients admitted to the Amiri hospital of Kuwait. The production of ESBL in all strains was confirmed by Vitek system and E-test. All the ESBL genes were amplified by PCR and examined by DNA sequencing. All these ESBL-positive isolates were resistant to ceftazidime and cefotaxime. DNA sequencing revealed an A815G point mutation in the bla (SHV )gene causing an asparagine (AAT) to aspartic acid (GAT) mutation at position 253 of the enzyme. This new mutation was assigned the unique number SHV-112, and the Genebank accession number EU477409. This study reports a new mutation in the SHV gene in K. pneumoniae with ESBL capability. There could be other mutations still to be found in ESBL genes of K. pneumoniae in Kuwait and probably in other middle eastern countries, and researchers in the region should make use of molecular techniques to look for more novel mutations in ESBL-producing strains of K. pneumoniae.


Asunto(s)
Infección Hospitalaria/microbiología , Brotes de Enfermedades , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/enzimología , Klebsiella pneumoniae/genética , Resistencia betalactámica/genética , beta-Lactamasas/genética , Secuencia de Aminoácidos , Antibacterianos/metabolismo , Antibacterianos/farmacología , Secuencia de Bases , Cefotaxima/metabolismo , Cefotaxima/farmacología , Ceftazidima/metabolismo , Ceftazidima/farmacología , Conjugación Genética , Infección Hospitalaria/epidemiología , ADN Bacteriano/genética , Farmacorresistencia Bacteriana Múltiple/genética , Electroforesis en Gel de Campo Pulsado , Humanos , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/aislamiento & purificación , Kuwait/epidemiología , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Mutación , Polimorfismo de Nucleótido Simple , Estudios Retrospectivos , beta-Lactamasas/biosíntesis , beta-Lactamasas/química
17.
J Biomed Mater Res B Appl Biomater ; 93(2): 394-400, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20119947

RESUMEN

Local delivery of antibiotics may provide the advantage of reducing the potential side effects associated with their systemic administration. This study assessed, in vitro, the antimicrobial efficacy of tetracycline hydrochloride (TCH) adsorbed onto Bio-Oss bone grafts against a range of pathogenic bacteria. Various levels of TCH were adsorbed onto Bio-Oss granules by immersing in TCH aqueous solutions of different initial concentrations for 48 h at room temperature. TCH release was assessed in phosphate buffered saline at 37 degrees C, and its antimicrobial efficacy, up to 96 h, was tested against two Gram-negative bacteria associated with periodontal diseases: Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans, and Porphyromonas gingivalis, and one Gram-positive bacterium associated with soft-tissue and bone infections: Staphylococcus aureus. The range of TCH concentrations studied was also assessed for cytotoxicity against osteoblast-like human osteosarcoma cell lines. The amount of TCH adsorbed and released from Bio-Oss was concentration dependent. All TCH adsorbed Bio-Oss resulted in a reduction of A. actinomycetemcomitans, P. gingivalis, and S. aureus and higher concentrations were generally more effective in reducing or eliminating bacterial growth. The proliferation of HOS cells was not substantially reduced except for the maximum concentration of TCH. In addition to its osteoconductive role, TCH adsorbed Bio-Oss could also be functional in negating systemically antibiotic prophylactic treatment in the prevention of implant or biomaterial related infections.


Asunto(s)
Antibacterianos/farmacología , Bacterias/crecimiento & desarrollo , Infecciones Bacterianas/prevención & control , Sustitutos de Huesos/farmacología , Sistemas de Liberación de Medicamentos , Minerales/farmacología , Tetraciclina/farmacología , Regeneración Ósea/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos
20.
J Clin Pathol ; 62(8): 739-42, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19406738

RESUMEN

BACKGROUND AND AIMS: Clinical hospitals need to correctly identify extended spectrum beta-lactamase (ESBL)-producing bacteria in infected patients to correctly treat the patient and avoid spreading antibiotic resistance. Kuwaiti hospitals use one laboratory test for detecting ESBL bacteria. This study evaluated whether that was sufficient to detect ESBL bacteria, and compared the Vitek system with other detection systems. METHODS: (Klebsiella pneumoniae, Escherichia coli, K oxytoca and Enterobacter cloacae) were collected from five different Kuwaiti main hospitals, all of which were flagged as ESBL-positive by the Vitek 2 system. The isolates were retested by the Vitek 2 system, and were also tested by double disc diffusion (DDD), the disc approximation test, the E-test and the MicroScan system for the detection of ESBLs. RESULTS: Retesting with the Vitek system revealed 100% compatibility with the results of the source hospitals. The MicroScan system, DDD, disc approximation test and E-test could detect ESBL in 199, 192, 178 and 205 isolates, respectively. CONCLUSIONS: Technically, the MicroScan and Vitek 2 systems were the least demanding method to detect ESBL as it is an integral part of the routine susceptibility test card. E-test strips were reliable but the most expensive of all techniques used. The DDD test and disc approximation, while relatively inexpensive, were technically subjective. The Vitek system may be very suitable in clinical laboratories, but would be better if accompanied with another test for detection of ESBL bacteria.


Asunto(s)
Infecciones por Enterobacteriaceae/diagnóstico , Enterobacteriaceae/enzimología , beta-Lactamasas/biosíntesis , Técnicas Bacteriológicas/métodos , Pruebas Antimicrobianas de Difusión por Disco , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Tiras Reactivas , Reproducibilidad de los Resultados
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