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BACKGROUND: Despite guidelines recommending inhalation therapy as the preferred choice, oral therapy is still widely used in the treatment of asthma in India. However, data about the level of asthma control and healthcare use in patients on oral anti-asthma medications are scarce.METHODS: A retrospective study was conducted to assess the level of asthma control and healthcare use in patients taking oral anti-asthma medications.RESULTS: The study population consisted of 381 adults randomly selected from health screening programmes. All subjects were already receiving oral anti-asthma medications; however, up to 72% had not been diagnosed with asthma by their treating doctors prior to the screening programmes. The cohort had a mean age of 48.26 ± 13.83 years (70% males) and mean peak expiratory flow of 245 ± 78.93 mL/sec. The mean Asthma Control Questionnaire 5 (ACQ-5) score was 2.53 ± 1.15, with respectively 33%, 49.3% and 32.6% reporting at least one episode of breathlessness, one emergency doctor visit and one hospitalisation due to asthma or its symptoms in the past year.CONCLUSION: Underdiagnosis and inappropriate management, as indicated by the poor asthma control and increased hospitalisations seen in this study, is probably a key contributor to the increased burden of the disease in India.
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Antiasmáticos , Asma , Adulto , Antiasmáticos/uso terapéutico , Asma/diagnóstico , Asma/tratamiento farmacológico , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is common among non-smokers exposed to solid fuel combustion at home. Different clinical characteristics in these patients may have significant therapeutic and prognostic implications.METHODS: We used medical record review and a questionnaire among COPD patients at 15 centres across India to capture data on demographic details, different types of exposures and clinical characteristics. Chest radiography and pulmonary function testing were performed in all 1984 cases; C-reactive protein and exhaled breath nitric oxide were measured wherever available.RESULTS: There were 1388 current or ex-smokers and 596 (30.0%) non-smokers who included 259 (43.5%) male and 337 (56.5%) female patients. Sputum production was significantly more common in smokers with COPD (P < 0.05). The frequency of acute symptomatic worsening, emergency visits and hospitalisation were significantly higher (P < 0.05) in non-smokers with COPD; however, intensive care unit admissions were similar in the two groups. There was no significant difference with respect to the use of bronchodilators, inhalational steroids or home nebulisation among smoker and non-smoker patients. The mean predicted forced expiratory volume in 1 sec in smokers (43.1%) was significantly lower than in non-smokers (46.5%).CONCLUSION: Non-smoker COPD, more commonly observed in women exposed to biomass fuels, was characterised by higher rate of exacerbations and higher healthcare resource utilisation.
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No Fumadores , Enfermedad Pulmonar Obstructiva Crónica , Broncodilatadores/uso terapéutico , Femenino , Volumen Espiratorio Forzado , Humanos , India/epidemiología , Masculino , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/epidemiologíaRESUMEN
INTRODUCTION: Many studies looked at outcomes and risk factors in laparoscopic cholecystectomies in general, including a few studies on risk factors and scoring systems in predicting conversion to open surgery. Little data has been produced on high-risk patients undergoing cholecystectomy. Identifying risk factors in this group could help stratify decision making regarding best management strategies.The aim of this study was to investigate outcomes of laparoscopic cholecystectomies in patients with ASA 3 and 4. METHODS: Data was collected and collated from a prospectively maintained database of all laparoscopic cholecystectomies performed by 13 general surgeons in a single unit. Case notes were reviewed for all patients with ASA 3 and 4 between 2013 and 2017. Data analysis was performed using R studio v 3.4. RESULTS: 244 cases were reviewed. Common bile duct was dilated in 52 cases (21.31%). Gall bladder wall was thick in 102 (41.8%) of the patients. Surgery was elective in 203 (83.2%) of the patients. ERCP was performed in 41 (16.9%) of the patients prior to surgery. 150 patients (62.2%) stayed for 1 day while 36 (14.9%) stayed for 2 days and the remaining 55 (22.9%) stayed for 3 days or more. Complications occurred in 37 (15.16%) of the patients while 23 (9.43%) of the patients were readmitted. 7 patients (2.87%) returned to theatre and 8 (3.28%) stayed in ITU post-op. Two patients died (0.82%). CONCLUSION: Laparoscopic cholecystectomies in higher risk populations are safe. Alternative methods such as cholecystostomy and ERCP may be of benefit in these patients.
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We report experimental results of the orientational order parameter, the apparent tilt angle, and the field-induced tilt angle for three chiral smectic liquid crystalline materials investigated using infrared (IR) polarized spectroscopy. The common feature in these materials is use of the core 5-methyl-2- pyrimidine benzoate as the central part of the mesogen. This core is terminated by siloxane or carbosilane chains on one of the ends and by the chiral alkoxy chains on the opposite. These compounds exhibit low concomitant layer shrinkage at the smectic A^{*} (SmA^{*}) to smectic C^{*} (SmC^{*}) transition temperature and within the SmC^{*} phase itself. The maximum layer shrinkage in SmC^{*} is observed as â¼1.5%. We calculate the apparent orientational order parameter, S_{app} in the laboratory reference frame from the observed IR absorbance for homeotropic aligned samples, and the true order parameter, S, is calculated using the measured tilt angle and is also interpolated from Iso-SmA^{*} transition temperature closer to SmC^{*} phase. The apparent tilt angle in the SmA^{*} phase calculated from a comparison of order parameters S and S_{app} is found to be significantly large. A low magnitude of S_{app} found for homeotropic aligned samples in the SmA^{*} phase indicates that the order parameter plays a vital role in determining the de Vries characteristics, especially of exhibiting larger apparent tilt angles. Furthermore there is a significant increase in the true order parameter at temperatures close to SmA^{*} to SmC^{*} transition temperature in all three compounds. The planar-aligned samples are used to study the dependence of induced tilt angle on the applied electric field. The generalized Langevin-Debye model given by Shen et al. reasonably fits the experimental data on the field-induced tilt angle. The results show that the dipole moment of the tilt correlated domain in SmA^{*} diverges as temperature is lowered to the SmA^{*}-SmC^{*} transition temperature. The generalized Langevin-Debye model is also found to be extremely effective in confirming some of the conclusions of the de Vries behavior.
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Surgical site infections (SSI) are a significant cause of post-surgical morbidity and mortality. The objectives of this study were to determine the prevalence of SSI and identify risk factors for infections following cesarean section (CS). A prospective study of SSI after CS was carried out from January 2014 to December 2016 using the methodology of the American National Nosocomial Infection Surveillance System. Suspected SSIs were confirmed clinically by the surgeon, and or, by culture. Seven thousand two hundred thirty five CS were performed with an overall SSI prevalence of 2.1%, increasing from 1.7% in 2014 to 2.95% in 2016 (P = 0.010). Of 152 cases of SSI, the prevalence of infection was 46.7% in women ⩽30 years and 53.3% in women >30 years (P = 0.119). Of 148 culture samples from as many women, 112 (75.7%) yielded growth of microorganisms with 42 (37.5%) of isolates being multi-drug resistant (MDR). Women who did not receive prophylactic antibiotics (35.5%) developed SSI more often than those who did (P < 0.0001). These findings suggest that emergency CS and inappropriate antibiotic prophylaxis are risk factors for developing SSI. In the light of the emergence of MDR bacteria there is a need to implement revised prophylactic antibiotic policy as part of antimicrobial stewardship to decrease SSI rates.
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Cesárea/efectos adversos , Hospitales Generales , Infección de la Herida Quirúrgica/epidemiología , Adulto , Femenino , Humanos , Kuwait/epidemiología , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Adulto JovenRESUMEN
Infrared and dielectric spectroscopic techniques are used to investigate the characteristics of two chiral smectics, namely, 1,1,3,3,5,5,5-heptamethyltrisiloxane 1-[4^{'}-(undecyl-1-oxy)-4-biphenyl(S,S)-2-chloro-3-methylpentanoate] (MSi_{3}MR_{11}) and tricarbosilane-hexyloxy-benzoic acid (S)-4'-(1-methyl-hexyloxy)-3'-nitro-biphenyl-4-yl ester (W599). The orientational features and the field dependencies of the apparent tilt angle and the dichroic ratio for homogeneous planar-aligned samples were calculated from the absorbance profiles obtained at different temperatures especially in the smectic-A* phase of these liquid crystals. The dichroic ratios of the C-C phenyl ring stretching vibrations were considered for the determination of the tilt angle at different temperatures and different voltages. The low values of the order parameter obtained with and without an electric field applied across the cell in the Sm-A^{*} phase for both smectics are consistent with the de Vries concept. The generalized Langevin-Debye model introduced in the literature for explaining the electro-optical response has been applied to the results from infrared spectroscopy. The results show that the dipole moment of the tilt-correlated domain diverges as the transition temperature from Sm-A^{*} to Sm-C^{*} is approached. The Debye-Langevin model is found to be extremely effective in confirming some of the conclusions of the de Vries chiral smectics and gives additional results on the order parameter and the dichroic ratio as a function of the field across the cell. Dielectric spectroscopy finds large dipolar fluctuations in the Sm-A^{*} phase for both compounds and again these confirm their de Vries behavior.
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Candiduria is considered one of the most controversial issues in patient management. Neither the diagnosis nor the optimal treatment options are standardized. This is further complicated by lack of defined laboratory criteria for diagnosis as most of the studies were set for bacterial rather than fungal urinary tract infection (UTI). Furthermore, since Candida species is a known commensal of the genitourinary tract its presence in the urine sample adds ambiguity to making a definitive diagnosis of candidal UTI. Guidelines for diagnosis and management of candiduria have changed considerably over the past decades. In 1960s, the condition was believed to be benign with no intervention required. However, over the years new dimensions were added to address the issues associated with candiduria until the latest Infectious Diseases Association of America (IDSA) guidelines were published in 2009, which indicated that there was an increase in the incidence of candiduria caused by more resistant non-Candida albicans species. Further complicating the issue is the observation that candiduria may be the only indicator of a more serious invasive candidiasis, especially in immunocompromised patients. Long-term urinary catheterization is considered to be the most significant risk factor for candiduria followed by antibiotic use and diabetes. Strategies for management are based on the evaluation of candiduria in the context of the clinical setting to determine its relevance and make an appropriate decision about the need for antifungal therapy. Fluconazole is the main drug used for its efficacy and least complications. Other options include bladder irrigation with amphotericin B, flucytosine or parenteral amphotericin B. Since azoles other than fluconazole and all echinocandins are poorly excreted in urine they have been found to be less effective in candiduric patients.
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Candidiasis/terapia , Candidiasis/orina , Infecciones Urinarias/terapia , Infecciones Urinarias/orina , Candida/aislamiento & purificación , Candidiasis/epidemiología , Infecciones Relacionadas con Catéteres/complicaciones , Infecciones Relacionadas con Catéteres/epidemiología , Infecciones Relacionadas con Catéteres/orina , Práctica Clínica Basada en la Evidencia/métodos , Humanos , Factores de Riesgo , Cateterismo Urinario/efectos adversos , Cateterismo Urinario/estadística & datos numéricos , Infecciones Urinarias/epidemiología , Infecciones Urinarias/microbiologíaRESUMEN
Major neurologic morbidity, such as seizures and encephalopathy, complicates 20-30% of organ and stem cell transplantation procedures. The majority of these disorders occur in the early posttransplant period, but recipients remain at risk for opportunistic infections and other nervous system disorders for many years. These long-term risks may be increasing as acute survival increases, and a greater number of "sicker" patients are exposed to long-term immunosuppression. Drug neurotoxicity accounts for a significant proportion of complications, with posterior reversible leukoencephalopathy syndrome, primarily associated with calcineurin inhibitors (i.e., cyclosporine and tacrolimus), being prominent as a cause of seizures and neurologic deficits. A thorough evaluation of any patient who develops neurologic symptoms after transplantation is mandatory, since reversible and treatable conditions could be found, and important prognostic information can be obtained.
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Enfermedades del Sistema Nervioso/etiología , Trasplante de Órganos/efectos adversos , Complicaciones Posoperatorias/etiología , Humanos , Infecciones Oportunistas/etiologíaRESUMEN
A nanoscopic exploratory measurement technique to measure voltage distribution across an operating semiconductor device in cryogenic temperature has been developed and established. The cross-section surface of the terahertz (THz) quantum cascade laser (QCL) has been measured that resolves the voltage distribution at nanometer scales. The electric field dissemination across the active region of the device has been attained under the device's lasing conditions at cryogenic temperature of 77 K.
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OBJECTIVE: To assess the quality of maternity care in an Indian metropolitan city. STUDY DESIGN: Three-stage cluster randomised cross-sectional survey. SETTING: Sixty selected colonies of Delhi. POPULATION: One thousand eight hundred and one subjects (of 2286 eligible) were enrolled from 118 446 houses. Women who had delivered a live viable birth in the past 6 months were selected for the study. METHODS: In stage 1, 20 wards (of 150) were selected using a probability-proportionate-to-size systematic method. In stage 2, one colony from each income stratum (high, middle and low) was selected from each ward by simple random sampling. In stage 3, a house-to-house survey was conducted to recruit 30 women for administering a peer-reviewed and pilot-trialled questionnaire. MAIN OUTCOME MEASURES: Caesarean section rate, induction rate and episiotomy rate. RESULTS: National health targets such as iron supplementation advice (>96%), tetanus vaccination (>81%), and ≥3 antenatal visits (>90%) were largely achieved across health care facilities but not in home deliveries. Interventions were lower in public than private hospitals: caesarean section [23.7% (20.2-27.7) versus 53.8% (49.3-58.3)], induction [20.6% (17.5-24.25) versus 30.8% (26.8-33.2)] and episiotomy [57.8% (52.3-63.1) versus 79.4% (71.0-85.9)]. Private hospitals achieved better labour support rates [1.1% (0.5-2.2) versus 14.6% (8.5-24.1)] and pain relief [0.9% (0.4-2.0) versus 9.9 (6.5-14.8)]. Pubic hair shaving [16.2% (11.5-22.5) versus 36.4% (29.9-43.4)], enema [20.2% (15.5-26.0) versus 57.3% (49.5-64.8)], and IV fluids during labour [44.0% (36.2-52.2) versus 38.7% (29.3-49.1)] were widely prevalent in public and private hospitals. CONCLUSION: Present practices fall short of evidence-based guidelines, with relative overuse of interventions in private hospitals and deficiency of patient-centred practices such as labour support in public hospitals.
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Adhesión a Directriz/estadística & datos numéricos , Hospitales Privados/normas , Hospitales Públicos/normas , Servicios Urbanos de Salud/normas , Adulto , Cesárea/estadística & datos numéricos , Estudios Transversales , Enema/estadística & datos numéricos , Episiotomía/estadística & datos numéricos , Medicina Basada en la Evidencia , Femenino , Fluidoterapia/estadística & datos numéricos , Encuestas de Atención de la Salud , Parto Domiciliario/normas , Parto Domiciliario/estadística & datos numéricos , Hospitales Privados/estadística & datos numéricos , Hospitales Públicos/estadística & datos numéricos , Humanos , India , Trabajo de Parto Inducido/estadística & datos numéricos , Trabajo de Parto , Manejo del Dolor/estadística & datos numéricos , Atención Perinatal/normas , Atención Perinatal/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Embarazo , Atención Prenatal/normas , Atención Prenatal/estadística & datos numéricos , Ultrasonografía Prenatal/estadística & datos numéricos , Servicios Urbanos de Salud/estadística & datos numéricos , Adulto JovenRESUMEN
OBJECTIVE: The study was undertaken to determine the prevalence of vulvovaginal candidiasis (VVC) among patients with vaginitis, frequency of different Candida species, and their susceptibility profile. PATIENTS AND METHODS: Over six months period, high vaginal swabs were cultured on Sabouraud's dextrose agar and isolates were identified by culture on CHROMagar Candida and Vitek2 yeast identification system or/and API 20C (BioMerieux, France). Antifungal susceptibility of the Candida isolates was determined by E-test against amphotericin B, flucytosine, fluconazole, voriconazole, posaconazole and caspofungin. RESULTS: One thousand seven hundred and fifty-two women with vaginitis were screened for the prevalence of Candida spp. Vaginal swab cultures of 231 (13.2%) women yielded Candida spp. The isolation rates of different species were as follows: Candida albicans (73.9%), Candida glabrata (19.8%), Candida kefir (1.94%), Candida tropicalis (0.96%), Candida parapsilosis (0.96%), Candida krusei (0.96%), Candida guilliermondii (0.96%), and Saccharomyces cerevisiae (0.52%). All strains of C. albicans and non-C. albicans were susceptible to most of the antifungal agents tested. CONCLUSION: The high frequency with which C. albicans was recovered and its azole susceptibility support the continued use of azole agents for empirical therapy of uncomplicated VVC. However, a larger controlled study is required to determine the role of non-C. albicans in recurrent VVC.
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Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candidiasis Vulvovaginal/microbiología , Adolescente , Adulto , Candida albicans/aislamiento & purificación , Candidiasis Vulvovaginal/epidemiología , Farmacorresistencia Fúngica , Femenino , Humanos , Kuwait/epidemiología , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/microbiología , Adulto JovenRESUMEN
BACKGROUND: Reference values of peak expiratory flow (PEF) in Indian adults have to date been derived locally, using an old (Wright) scale peak flow meter. There are thus no reliable reference values for PEF for Indians and this formed the aim of the study. MATERIALS AND METHODS: A European Union (EU) scale peak flow meter (PFM) was used for the study. A respiratory health and demographic questionnaire was administered to 1000 male and female adults from randomly selected locations in the country in this multi centric study. The locations represented different geographic, ethnic, and socioeconomic backgrounds. Patients were stratified according to height and age. The PEF values were measured using the Breathometer™ (Cipla Ltd., India) with EU scale. Reference equations were derived from multiple regression analysis. RESULTS: A total of 3608 participants were excluded. In 80% of the remaining 6138 healthy adults (M: 3720; F: 2418), the predicted regression equations were derived. Gender, age, and height were the significant determinants of PEF. The equations in L/minute are: Females: PEF = -1.454 (Age) + 2.368 (Height) Males: PEF = -1.807 (Age) + 3.206 (Height). The derived equation was validated by comparing the predicted PEF values with the measured values in the remaining sample of 20% (Mean ΔPEF: M = 1.85 L/minute, CI = -2.76, 6.47; F = 1.64, CI = -2.89, 6.18). An Indian adult with average height and age was found to have approximately 30% lower PEF compared to the corresponding European adult using the Nunn and Gregg equation. CONCLUSION: We derived reference values of PEF for Indian adults using a validated EU scale peak flow meter.
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Ápice del Flujo Espiratorio , Pruebas de Función Respiratoria/instrumentación , Adulto , Factores de Edad , Pueblo Asiatico , Estatura , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Valores de Referencia , Análisis de Regresión , Pruebas de Función Respiratoria/estadística & datos numéricos , Sensibilidad y Especificidad , Factores Sexuales , Encuestas y CuestionariosRESUMEN
The distribution of charge carriers inside the active region of a terahertz (THz) quantum cascade laser (QCL) has been measured with scanning spreading resistance microscopy (SSRM) and scanning capacitance microscopy (SCM). Individual quantum well-barrier modules with a 35.7-nm single module thickness in the active region of the device have been resolved for the first time using high-resolution SSRM and SCM techniques at room temperature. SSRM and SCM measurements on the quantum well-barrier structure were calibrated utilizing known GaAs dopant staircase samples. Doping concentrations derived from SSRM and SCM measurements were found to be in quantitative agreement with the designed average doping values of the n-type active region in the terahertz quantum cascade laser. The secondary ion mass spectroscopy provides a partial picture of internal device parameters, and we have demonstrated with our results the efficacy of uniting calibrated SSRM and SCM to delineate quantitatively the transverse cross-sectional structure of complex two-dimensional terahertz quantum cascade laser devices.
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The mode of presentation of coeliac disease has been changing to more atypical or silent disease. Few studies described the clinical presentation of adult coeliac disease in Ireland in recent years. We retrospectively collected the clinical data for all patients who had a diagnosis of coeliac disease made in our centre between January 07 and December 08. Forty seven adults, predominantly females (n = 30), had a confirmed diagnosis of coeliac disease made during the study period. In our patient cohort, the presenting symptom was diarrhoea in 19 (40%) patients, while 16 patients (34%) did not have any G.I. symptoms, 10 (21%) presented with anaemia. Females presented at a significantly younger age compared to males, with median ages at diagnosis of 44.5 and 57 years, respectively (p = 0.04). Females also presented more commonly with non G.I. symptoms (p = 0.07). The reasons behind this gender difference need further study.
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Enfermedad Celíaca/diagnóstico , Adulto , Índice de Masa Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Transglutaminasas/análisis , Pérdida de PesoRESUMEN
Most laboratory evolution studies that characterize evolutionary adaptation genomically focus on genetically simple traits that can be altered by one or few mutations. Such traits are important, but they are few compared with complex, polygenic traits influenced by many genes. We know much less about complex traits, and about the changes that occur in the genome and in gene expression during their evolutionary adaptation. Salt stress tolerance is such a trait. It is especially attractive for evolutionary studies, because the physiological response to salt stress is well-characterized on the molecular and transcriptome level. This provides a unique opportunity to compare evolutionary adaptation and physiological adaptation to salt stress. The yeast Saccharomyces cerevisiae is a good model system to study salt stress tolerance, because it contains several highly conserved pathways that mediate the salt stress response. We evolved three replicate lines of yeast under continuous salt (NaCl) stress for 300 generations. All three lines evolved faster growth rate in high salt conditions than their ancestor. In these lines, we studied gene expression changes through microarray analysis and genetic changes through next generation population sequencing. We found two principal kinds of gene expression changes, changes in basal expression (82 genes) and changes in regulation (62 genes). The genes that change their expression involve several well-known physiological stress-response genes, including CTT1, MSN4 and HLR1. Next generation sequencing revealed only one high-frequency single-nucleotide change, in the gene MOT2, that caused increased fitness when introduced into the ancestral strain. Analysis of DNA content per cell revealed ploidy increases in all the three lines. Our observations suggest that evolutionary adaptation of yeast to salt stress is associated with genome size increase and modest expression changes in several genes.
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Adaptación Biológica , Evolución Biológica , Saccharomyces cerevisiae/genética , Salinidad , Cloruro de Sodio/farmacología , Electroforesis en Gel de Campo Pulsado , Amplificación de Genes , Eliminación de Gen , Duplicación de Gen , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Ploidias , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/efectos de los fármacos , Análisis de Secuencia de ADNAsunto(s)
Antibacterianos/uso terapéutico , Bronquiectasia/tratamiento farmacológico , Colistina/uso terapéutico , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa , Anciano , Fibrosis Quística/complicaciones , Evaluación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Samples were collected every 2-4 weeks from a set of 37 monitoring wells over a period of 2-3 years in Araihazar, Bangladesh, to evaluate the temporal variability of groundwater composition for As and other constituents. The monitoring wells are grouped in 6 nests and span the 5-91 m depth range. Concentrations of As, Ca, Fe, K, Mg, Mn, Na, P, and S were measured by high-resolution ICPMS with a precision of 5% or better; concentrations of Cl were measured by ion chromatography. In shallow wells <30 m deep, As and P concentrations generally varied by <30%, whereas concentrations of the major ions (Na, K, Mg, Ca and Cl) and the redox-sensitive elements (Fe, Mn, and S) varied over time by up to +/-90%. In wells tapping the deeper aquifers >30 m often below clay layers concentrations of groundwater As were much lower and varied by <10%. The concentrations of major cations also varied by <10% in these deep aquifers. In contrast, the concentration of redox-sensitive constituents Fe, S, and Mn in deep aquifers varied by up to 97% over time. Thus, strong decoupling between variations in As and Fe concentrations is evident in groundwaters from shallow and deep aquifers. Comparison of the time series data with groundwater ages determined by (3)H/(3)He and (14)C dating shows that large seasonal or inter-annual variations in major cation and chloride concentrations are restricted to shallow aquifers and groundwater recharged <5 years ago. There is no corresponding change in As concentrations despite having significant variations of redox sensitive constituents in these very young waters. This is attributed to chemical buffering due to rapid equilibrium between solute and solid As. At two sites where the As content of groundwater in existing shallow wells averages 102 microg/L (range: <5 to 648 microg/L; n=118) and 272 microg/L (range: 10 to 485 microg/L; n=65), respectively, a systematic long-term decline in As concentrations lends support to the notion that flushing may slowly deplete an aquifer of As. Shallow aquifer water with >5 years (3)H/(3)He age show a constant As:P molar ratio of 9.6 over time, suggesting common mechanisms of mobilization.
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Arsénico/análisis , Monitoreo del Ambiente , Agua Dulce/química , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua , Bangladesh , Agua Dulce/análisis , Abastecimiento de Agua/análisis , Abastecimiento de Agua/normasRESUMEN
OBJECTIVE: To investigate the prevalence of antibiotic resistance among Staphylococcus aureus isolated in Kuwaiti hospitals. MATERIALS AND METHODS: S. aureus were isolated and identified following standard microbiological methods. Antibacterial susceptibility test was performed by disk diffusion and the measurement of minimum inhibitory concentration with E-test strips. RESULTS: A total of 1,846 S. aureus isolates were analyzed from 13 hospitals between 1 March and 30 October 2005. They were isolated from 1,765 (95.6%) inpatients and 81 (4.4%) outpatients. Methicillin resistance was detected in 588 (32.0%) of the isolates. The methicillin-resistant S. aureus (MRSA) consisted of 461 (78%) multiresistant and 127 (22%) nonmultiresistant isolates. The nonmultiresistant MRSA consisted of epidemic MRSA-15 and community-associated MRSA. The community-associated MRSA was detected in all hospitals with MRSA, indicating its establishment in Kuwaiti hospitals. The proportion of isolates resistant to gentamicin, kanamycin, erythromycin, tetracycline, ciprofloxacin, fusidic acid and trimethoprim was higher among MRSA than methicillin-susceptible S. aureus (MSSA) isolates. Twenty-four and 22% of MRSA and MSSA isolates, respectively, expressed reduced susceptibility to vancomycin (minimum inhibitory concentration = 3-4 mg/l). CONCLUSION: The study revealed the presence of methicillin resistance in 32% of S. aureus isolated in Kuwaiti hospitals and revealed an increase in the number of MRSA and MSSA with reduced susceptibility to vancomycin.
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Farmacorresistencia Bacteriana , Hospitales/estadística & datos numéricos , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Antibacterianos/uso terapéutico , Humanos , Kuwait/epidemiología , Resistencia a la Meticilina , Pruebas de Sensibilidad Microbiana , Vigilancia de la Población , Prevalencia , Infecciones Estafilocócicas/tratamiento farmacológico , Teicoplanina/uso terapéutico , Resistencia a la VancomicinaRESUMEN
Employing the dielectric relaxation spectroscopy technique, we have observed two different characteristics of the collective relaxation mode of an incommensurate SmC(α)(*) phase. Recent theoretical advances predict two different natures for the dielectric relaxation mode in the SmC(α)(*) phase. Our experimental results confirm two different behaviours of the relaxation mode in different temperature ranges for this phase for one unique compound having an exceptionally wide temperature range (â¼9 °C) for the SmC(α)(*) phase.