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1.
Environ Sci Process Impacts ; 24(12): 2450-2464, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36444711

RESUMEN

Fecal pollution of surface waters in the karst-dominated Edwards aquifer is a serious concern as contaminated waters can rapidly transmit to groundwaters, which are used for domestic purposes. Although microbial source tracking (MST) detects sources of fecal pollution, integrating data related to environmental processes (precipitation) and land management practices (septic tanks) with MST can provide better understanding of fecal contamination fluxes to implement effective mitigation strategies. Here, we investigated fecal sources and their spatial origins at recharge and contributing zones of the Edwards aquifer and identified their relationship with nutrients in different environmental/land-use conditions. During March 2019 to March 2020, water samples (n = 295) were collected biweekly from 11 sampling sites across four creeks and analyzed for six physico-chemical parameters and ten fecal indicator bacteria (FIB) and MST-based qPCR assays targeting general (E. coli, Enterococcus, and universal Bacteroidales), human (BacHum and HF183), ruminant (Rum2Bac), cattle (BacCow), canine (BacCan), and avian (Chicken/Duck-Bac and GFD) fecal markers. Among physico-chemical parameters, nitrate-N (NO3-N) concentrations at several sites were higher than estimated national background concentrations for streams. General fecal markers were detected in the majority of water samples, and among host-associated MST markers, GFD, BacCow, and Rum2Bac were more frequently detected than BacCan, BacHum, and HF183, indicating avian and ruminant fecal contamination is a major concern. Cluster analysis results indicated that sampling sites clustered based on precipitation and septic tank density showed significant correlation (p < 0.05) between nutrients and FIB/MST markers, indicating these factors are influencing the spatial and temporal variations of fecal sources. Overall, results emphasize that integration of environmental/land-use data with MST is crucial for a better understanding of nutrient loading and fecal contamination.


Asunto(s)
Agua Subterránea , Microbiología del Agua , Perros , Animales , Bovinos , Humanos , Escherichia coli , Marcadores Genéticos , Monitoreo del Ambiente/métodos , Contaminación del Agua/análisis , Heces/microbiología , Bacterias/genética , Agua/análisis
2.
Curr Opin Environ Sci Health ; 27: 100362, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35402756

RESUMEN

The COVID-19 pandemic has been challenging for various institutions such as school systems due to widespread closures. As schools re-open their campuses to in-person education, there is a need for frequent screening and monitoring of the virus to ensure the safety of students and staff and to limit risk to the surrounding community. Wastewater surveillance (WWS) of SARS-CoV-2 is a rapid and economical approach to determine the extent of COVID-19 in the community. The focus of this review is on the emergence of WWS as a tool for safe return to school campuses, taking into account methodological considerations such as site selection, sample collection and processing, SARS-CoV-2 quantification, and data interpretation. Recently published studies on the implementation of COVID-19 WWS on school and college campuses were reviewed. While there are several logistical and technical challenges, WWS can be used to inform decision-making at the school campus and/or building level.

3.
ACS ES T Water ; 2(11): 2060-2069, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-37552728

RESUMEN

The purpose of this study was to conduct a correlative assessment of SARS-CoV-2 RNA concentrations in wastewater with COVID-19 cases and a systematic evaluation of the effect of using different virus concentration methods and recovery and normalization approaches. We measured SARS-CoV-2 RNA concentrations at two different wastewater treatment plants (WWTPs) in the Bexar County of Texas from October 2020 to May 2021 (32 weeks) using reverse transcription droplet digital PCR (RT-ddPCR). We evaluated three different adsorption-extraction (AE) based virus concentration methods (acidification, addition of MgCl2, or without any pretreatment) using bovine coronavirus (BCoV) as surrogate virus and observed that the direct AE method showed the highest mean recovery. COVID-19 cases were correlated significantly with SARS-CoV-2 N1 concentrations in Salitrillo (ρ = 0.75, p < 0.001) and Martinez II (ρ = 0.68, p < 0.001) WWTPs, but normalizing to a spiked recovery control (BCoV) or a fecal marker (HF183) reduced correlations for both treatment plants. The results generated in this 32-week monitoring study will enable researchers to prioritize the virus recovery method and subsequent correlation studies for wastewater surveillance.

4.
Int J Surg Case Rep ; 85: 106257, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34343794

RESUMEN

INTRODUCTION: Intravenous leiomyomatosis (ILV) is a rare pathology, part of leiomyoma beyond the uterus (LBU), characterized by benign smooth muscle cell tumor outside of the uterus and mainly affecting premenopausal woman with a medical history of leiomyoma or gynecologic surgical treatment. The treatment depends on the localization of the tumor, age of the patient, initial size, symptoms and the suitability for surgery but should always aims in toto surgical resection. CASE PRESENTATION: Retrospective case series and review of literature. CLINICAL DISCUSSION: Symptoms presented by the patient were aspecific and only localized in the pelvic area. All cases were fortuitous histopathological diagnosis. No relapse was. Two out of 5 patients have pulmonary nodules, only one was biopsied and diagnosed with PBML (pulmonary benign metastasizing leiomyoma). CONCLUSION: IVL and BML are rare disease that can co-exist. Because of tumoral hormonal receptors, hormonotherapy could be an optional treatment but to date no clear efficacy is demonstrated. In case of high recurrence risk such as voluminous initial mass, impairment of broad ligament, failure of total surgical resection, adjuvant hormonotherapy could be useful. Recurrence rate is about 16.6-30% and can occur even dozen years later and even after radical surgery, justifying a regular follow up.

5.
FEMS Microbes ; 2: xtab015, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-37334234

RESUMEN

The purpose of this study was to conduct a preliminary assessment of the levels of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in wastewater at the Salitrillo Wastewater Treatment Plant in Texas during the initial peak of coronavirus disease 2019 (COVID-19) outbreak. Raw wastewater influent (24 h composite, time-based 1 L samples, n = 13) was collected weekly during June-August 2020. We measured SARS-CoV-2 RNA in wastewater by reverse transcription droplet digital PCR using the same N1 and N2 primer sets as employed in COVID-19 clinical testing. Virus RNA copies for positive samples (77%) ranged from 1.4 × 102 to 4.1 × 104 copies per liter of wastewater, and exhibited both increasing and decreasing trends, which corresponded well with the COVID-19 weekly infection rate (N1: ρ = 0.558, P = 0.048; N2: ρ = 0.487, P = 0.092). A sharp increase in virus RNA concentrations was observed during July sampling dates, consistent with the highest number of COVID-19 cases reported. This could be attributed to an increase in the spread of COVID-19 infection due to the Fourth of July holiday week gatherings (outdoor gatherings were limited to 100 people during that time). Our data show that wastewater surveillance is an effective tool to determine trends in infectious disease prevalence, and provide complementary information to clinical testing.

6.
Chemosphere ; 261: 127775, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32738717

RESUMEN

The short-term effects of Mn2O3 nanoparticles (NPs) were examined for nitrifying bacterial enrichments exposed under low and high dissolved oxygen (DO) conditions using substrate (ammonia) specific oxygen uptake rates (sOUR), reverse transcriptase - quantitative polymerase chain reaction (RT-qPCR) assays, and by analysis of 16S rRNA sequences. Samples from nitrifying bioreactor were exposed in batch vessels to Mn2O3 NPs (1, 5 and 10 mg/L) for either 1 or 3 h under no additional aeration or 0.25 L/min aeration. There was increase in nitrification inhibition as determined by sOUR with increasing dosages of Mn2O3 NPs for both low and high DO. At 10 mg/L Mn2O3 NPs, the inhibition was about 7-10% for 1 and 3 h exposure in both cases. There was notable reduction in the transcript levels of amoA, hao and nirK for 10 mg/L of Mn2O3 NPs under 3 h, high DO exposure, which corresponded well with sOUR. The 16S rRNA sequencing showed that there was an inhibitory effect on ammonia oxidizers activity upon exposure to 10 mg/L of Mn2O3 NPs. Collectively, the findings in this study advanced understanding of the different effects of Mn2O3 NPs on nitrifying bacteria.


Asunto(s)
Nanopartículas/toxicidad , Nitrificación/fisiología , Amoníaco/metabolismo , Bacterias/metabolismo , Reactores Biológicos/microbiología , Expresión Génica , Nitrificación/efectos de los fármacos , Oxidación-Reducción , Oxígeno/metabolismo , ARN Ribosómico 16S/genética
7.
Sci Total Environ ; 742: 140512, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-32721719

RESUMEN

The interaction of anaerobic microorganisms with carbon nanotube/polymer nanocomposites (CNT/PNC) will play a major role in determining their persistence and environmental fate at the end of consumer use when these nano-enabled materials enter landfills and encounter wastewater. Motivated by the need to understand how different parameters (i.e., polymer type, microbial phenotype, CNT characteristics) influence CNT/PNC biodegradation rates, we have used volumetric biogas measurements and kinetic modeling to study biodegradation as a function of polymer type and CNT properties. In one set of experiments, oxidized multiwall carbon nanotubes (O-MWCNTs) with a range of CNT loadings 0-5% w/w were incorporated into poly-ε-caprolactone (PCL) and polyhydroxyalkanoates (PHA) matrices and subjected to biodegradation by an anaerobic microbial community. For each CNT/PNC, complete polymer biodegradation was ultimately observed, although the rate of biodegradation was inhibited above certain critical CNT loadings dependent upon the polymer type. Higher loadings of pristine MWCNTs were needed to decrease the rate of polymer biodegradation compared to O-MWCNTs, an effect ascribed principally to differences in CNT dispersion within the polymer matrices. Above certain CNT loadings, a CNT mat of similar shape to the initial PNC was formed after polymer biodegradation, while below this threshold, CNT aggregates fragmented in the media. In situations where biodegradation was rapid, methanogen growth was disproportionately inhibited compared to the overall microbial community. Analysis of the results obtained from this study indicates that the inhibitory effect of CNTs on polymer biodegradation rate is greatest under conditions (i.e., polymer type, microbial phenotype, CNT dispersion) where biodegradation of the neat polymer is slowest. This new insight provides a means to predict the environmental fate, persistence, and transformations of CNT-enabled polymer materials.


Asunto(s)
Nanocompuestos , Nanotubos de Carbono , Biodegradación Ambiental , Polímeros
8.
Sci Total Environ ; 639: 804-814, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-29803051

RESUMEN

The properties and commercial viability of biodegradable polymers can be significantly enhanced by the incorporation of carbon nanotubes (CNTs). The environmental impact and persistence of these carbon nanotube/polymer nanocomposites (CNT/PNCs) after disposal will be strongly influenced by their microbial interactions, including their biodegradation rates. At the end of consumer use, CNT/PNCs will encounter diverse communities of microorganisms in landfills, surface waters, and wastewater treatment plants. To explore CNT/PNC biodegradation under realistic environmental conditions, the effect of multi-wall CNT (MWCNT) incorporation on the biodegradation of polyhydroxyalkanoates (PHA) was investigated using a mixed culture of microorganisms from wastewater. Relative to unfilled PHA (0% w/w), the MWCNT loading (0.5-10% w/w) had no statistically significant effect on the rate of PHA matrix biodegradation. Independent of the MWCNT loading, the extent of CNT/PNC mass remaining closely corresponded to the initial mass of CNTs in the matrix suggesting a lack of CNT release. CNT/PNC biodegradation was complete in approximately 20 days and resulted in the formation of a compressed CNT mat that retained the shape of the initial CNT/PNC. This study suggests that although CNTs have been shown to be cytotoxic towards a range of different microorganisms, this does not necessarily impact the biodegradation of the surrounding polymer matrix in mixed culture, particularly in situations where the polymer type and/or microbial population favor rapid polymer biodegradation.


Asunto(s)
Biodegradación Ambiental , Nanocompuestos , Nanotubos de Carbono , Polímeros/metabolismo , Aerobiosis
9.
Soft Matter ; 12(23): 5146-53, 2016 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-27194365

RESUMEN

Conducting polymers such as poly(3,4-ethylenedioxythiophene) polystyrene sulfonate ( PEDOT: PSS) are increasingly used to interface electronics with biology. Their wettability, however, remains poorly understood. We show that the frequently-used sessile drop technique yields results that are strongly dependent on the experimental conditions (measurement duration and relative humidity), due to the hydrogel-like behavior of PEDOT: PSS. In contrast, the captive bubble technique on a fully wet film overcomes these limitations. Dynamic wettability measurements provide hysteresis values for this polymer and clarify the physical meaning of the static contact angles measured by sessile drop and captive bubble. Finally we show that aging the films in water leads to loss of PSS chains which makes the films more hydrophobic. The addition of a crosslinker reduces and slows down these effects.

10.
Physiol Meas ; 36(3): 547-60, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25690269

RESUMEN

Kinematic functional evaluation with body-worn sensors provides discriminative and responsive scores after shoulder surgery, but the optimal movements' combination has not yet been scientifically investigated. The aim of this study was the development of a simplified shoulder function kinematic score including only essential movements. The P Score, a seven-movement kinematic score developed on 31 healthy participants and 35 patients before surgery and at 3, 6 and 12 months after shoulder surgery, served as a reference. Principal component analysis and multiple regression were used to create simplified scoring models. The candidate models were compared to the reference score. ROC curve for shoulder pathology detection and correlations with clinical questionnaires were calculated. The B-B Score (hand to the Back and hand upwards as to change a Bulb) showed no difference to the P Score in time*score interaction (P > .05) and its relation with the reference score was highly linear (R(2) > .97). Absolute value of correlations with clinical questionnaires ranged from 0.51 to 0.77. Sensitivity was 97% and specificity 94%. The B-B and reference scores are equivalent for the measurement of group responses. The validated simplified scoring model presents practical advantages that facilitate the objective evaluation of shoulder function in clinical practice.


Asunto(s)
Movimiento/fisiología , Examen Físico/métodos , Índice de Severidad de la Enfermedad , Hombro/fisiología , Hombro/fisiopatología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Húmero/fisiología , Húmero/fisiopatología , Masculino , Persona de Mediana Edad , Análisis de Componente Principal , Análisis de Regresión , Hombro/cirugía , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento
11.
Med Eng Phys ; 36(1): 49-56, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24075589

RESUMEN

In clinical settings, the cervical range of motion (ROM) is commonly used to assess cervical spine function. This study aimed at assessing cervical spine mobility based on head and thorax kinematics measured with a wearable inertial system (WS). Sequences of imposed active head movements (lateral bending, axial rotation and flexion-extension) were recorded in ten controls and 13 patients who had undergone an arthrodesis. Orientation of the head relative to the thorax was computed in terms of 3D helical angles and compared with the values obtained using an optoelectronic reference system (RS). Movement patterns from WS and RS showed excellent concurrent validity (CMC up to 1.00), but presented slight differences of bias (mean bias<2.5°) and dispersion (mean dispersion<4.2°). ROM obtained using WS also showed some differences compared to RS (mean difference<5.7°), within the range of those reported in literature. WS enabled the observation of the same significant differences between controls and patients as RS. Moreover, ROM from WS presented good test-retest repeatability (ICC between 0.63 and 0.99 and SEM<6.2°). In conclusion, WS can provide angles and ROM comparable to those obtained with RS and relevant for the cervical assessment after treatment.


Asunto(s)
Vértebras Cervicales/fisiología , Equipos y Suministros Eléctricos , Movimiento , Dispositivos Ópticos , Rango del Movimiento Articular , Adulto , Anciano , Artrodesis , Estudios de Casos y Controles , Vértebras Cervicales/fisiopatología , Vértebras Cervicales/cirugía , Humanos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Adulto Joven
12.
Clin Biomech (Bristol, Avon) ; 28(4): 364-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23578604

RESUMEN

BACKGROUND: Evaluation of cervical spine mobility after surgery is mainly based on the measurement of the range of motion during imposed movements. It can thus be questionable if this assessment represents the mobility experienced during daily life. The goal of this study was to propose a new evaluation tool based on the monitoring of cervical spine movement during daily activities. METHODS: The detection of cervical movement and the determination of primary motion component (lateral bending, axial rotation or flexion-extension), using two inertial sensors, were first validated in laboratory settings. Fifteen patients who underwent a cervical arthrodesis and nine healthy control subjects were monitored during their daily activity for half a day. The frequency of cervical movement was quantified according to posture, i.e. static and walking periods. The amplitude and velocity of cervical movement were evaluated using the median and cumulative distribution function. FINDINGS: The movement detection and classification showed an excellent performance (sensitivity and specificity>94%). For the daily monitoring, the patients presented a movement frequency similar to controls, whereas the amplitude and velocity in patients were lower than in controls (P<0.05). The differences between patients and controls were larger for the velocity parameters (effect sizes>0.37 and >0.54 for static and walking periods respectively) than for the amplitude parameters. INTERPRETATION: Body-worn inertial sensors enable the quantitative evaluation of global cervical movement. The movement amplitude and velocity during free-living conditions can be used as objective parameters to evaluate the cervical spine mobility after treatment.


Asunto(s)
Actividades Cotidianas , Vértebras Cervicales/fisiopatología , Monitoreo Fisiológico/métodos , Rango del Movimiento Articular , Vértebras Cervicales/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Movimiento (Física) , Movimiento , Postura , Rotación , Fusión Vertebral
13.
Int J Gynecol Cancer ; 16 Suppl 1: 356-60, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16515622

RESUMEN

Aggressive angiomyxoma (AAM) is a rare tumor that preferentially involves the pelvis and perineal regions and arises from the connective tissue. Its cause and pathogenesis are unknown at present. Treatment typically involves surgery, and despite apparently complete resection, local recurrences are common. We describe a case of a large angiomyxoma of the left pelvis in a 59-year-old woman who underwent two surgical excisions. The first had been done in May 1998. She developed a local recurrence in December 1998. A palliative resection with macroscopic residuals was performed in February 2001, followed by radiation therapy with a total dose of 60 Gy. The diagnosis was revised at the time of the second operation. Initially, the tumor was diagnosed as angiomyofibroblastoma. Follow-up 3 years after the radiation treatment revealed no recurrence. The time of the local control achieved as yet is already longer than the former time to progression between the first two surgical procedures. This is, to our knowledge, the second description of a therapeutic irradiation of a recurrent AAM. Radiation therapy is able to control a recurrent AAM for at least 3 years.


Asunto(s)
Mixoma/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Neoplasias Pélvicas/radioterapia , Neoplasias Retroperitoneales/radioterapia , Nalgas , Femenino , Humanos , Persona de Mediana Edad , Mixoma/patología , Mixoma/cirugía , Invasividad Neoplásica , Recurrencia Local de Neoplasia/patología , Neoplasias Pélvicas/patología , Neoplasias Pélvicas/cirugía , Perineo , Reoperación , Neoplasias Retroperitoneales/patología , Neoplasias Retroperitoneales/cirugía
14.
Ann Chir ; 131(5): 306-10, 2006 May.
Artículo en Francés | MEDLINE | ID: mdl-16545337

RESUMEN

AIM OF STUDY: To report cases from Vietnam of intestinal tuberculosis disease, which is uncommon but did not disappear in occidental countries. MATERIALS AND METHODS: Seventy-six patients were included in this retrospective study. Mean age was 40 years and sex ratio M/F was 6. Diagnosis was established on pathological examination of resected specimen or on presence of Mycobacterium tuberculosis or by polymerase chain reaction. RESULTS: Intestinal obstruction or subobstruction was the most usual symptom (68%), and thereafter peritoneal symptoms with pain and tenderness (17%). Five patients had intractable digestive haemorrhage. Thirty-six patients had no past history or active pulmonary tuberculosis (47%). Lesions of stenosis on barium enema and thickness of intestinal wall on CT-scan were not specific. Sixty-two patients were operated on (82%) and 14 were not. Surgical techniques differed according symptoms, site and type of lesions. Intestinal resections were performed in half of the patients, others undergoing stomies or enterolysis. There were eight postoperative deaths (13% of patients operated on), seven out of these deaths were attributable to cachexy. In the postoperative period, all the patients were medically treated and follow-up in the antituberculosis centre of Hanoi. CONCLUSION: Symptomatology and operative findings of intestinal tuberculosis are similar to those observed in Crohn's disease, and sometimes in amoeboma or lymphoma. In face of stenosis and intestinal wall thickness, probability of intestinal tuberculosis is high in endemic area, but diagnosis must be suspected in occidental countries, mainly in patients immigrated coming from these areas, patients with immuno-deficiency even if they did not have past or present pulmonary tuberculosis.


Asunto(s)
Tuberculosis Gastrointestinal/epidemiología , Adolescente , Adulto , Anciano , Antituberculosos/uso terapéutico , Caquexia/mortalidad , Constricción Patológica/epidemiología , Enterostomía , Femenino , Estudios de Seguimiento , Hemorragia Gastrointestinal/epidemiología , Humanos , Obstrucción Intestinal/epidemiología , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/aislamiento & purificación , Complicaciones Posoperatorias , Estudios Retrospectivos , Salud Rural/estadística & datos numéricos , Tuberculosis Gastrointestinal/mortalidad , Tuberculosis Pulmonar/epidemiología , Salud Urbana/estadística & datos numéricos , Vietnam/epidemiología
16.
Eur J Neurol ; 10(1): 45-52, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12534992

RESUMEN

The new antiepileptic drug vigabatrin (VGB) increases gamma-aminobutyric acid (GABA) in the brain. We compared GABA+/Cr signals measured focus-near and focus-distant and correlated it with the degree of response to VGB. Brain GABA+/Cr signals were measured in 17 epileptic patients in structurally normal appearing tissue by nuclear proton magnetic resonance (1H-NMR) spectroscopy using a special editing sequence for GABA. In 11 patients the measurements were done in brain areas distant to focus and in six near to focus. Full-responders (seizure reduction of >or=50% at the end of the treatment phase) and partial-responders (seizure reduction of >or=50% at the end of the first month of treatment but

Asunto(s)
Encéfalo/efectos de los fármacos , Epilepsia Parcial Compleja/tratamiento farmacológico , Espectroscopía de Resonancia Magnética/métodos , Vigabatrin/farmacología , Ácido gamma-Aminobutírico/análisis , Adolescente , Adulto , Encéfalo/metabolismo , Radioisótopos de Cromo , Epilepsia Parcial Compleja/metabolismo , Femenino , Humanos , Espectroscopía de Resonancia Magnética/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Estadísticas no Paramétricas , Vigabatrin/uso terapéutico , Ácido gamma-Aminobutírico/metabolismo
17.
Ann Pharm Fr ; 60(6): 403-9, 2002 Nov.
Artículo en Francés | MEDLINE | ID: mdl-12514507

RESUMEN

Synthesis and physico-chemical properties of some 3-benzyl- and 3-phenacyl-4-thioxo-5-benzylidenethiazolidin-2-one derivatives are described. Fifteen new compounds were synthesized from thiazolidin-2-one by thionation of the 4-carbonyle, alkylation of the 3-N and aldolisation-crotonisation of 5-CH(2) with aromatic aldehydes. Soon, these new compounds will be tested for their bacteriostatic activity.


Asunto(s)
Antiinfecciosos/síntesis química , Tiazoles/síntesis química , Tiazoles/farmacología , Alquilación , Antiinfecciosos/farmacología , Indicadores y Reactivos
18.
Farmaco ; 56(9): 689-93, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11680813

RESUMEN

The synthesis and physicochemical properties of 4-butyl-2H-benzo[1,4]thiazin-3-one derivatives are described. These new compounds were synthesised by alkylation in 4-N position and acylation and/or alkylation of 6-NH2 by phase transfer catalysis. Acid hydrolysis of 6-alkylacylamino group yielded 6-alkylamino-4-butyl-2H-benzo[1,4]thiazin-3-ones. The antimicrobial in vitro activity was determined on five compounds.


Asunto(s)
Antiinfecciosos/síntesis química , Tiazinas/síntesis química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Pruebas de Sensibilidad Microbiana , Tiazinas/farmacología
19.
J Infect Dis ; 183(7): 1156-60, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11237848

RESUMEN

Control of Salmonella enterica serovar Typhimurium (S. typhimurium) infection in the mouse model of typhoid fever is critically dependent on the natural resistance-associated macrophage protein 1 (Nramp1). In this study, we examined the role of genetic polymorphisms in the human homologue, NRAMP1, in resistance to typhoid fever in southern Vietnam. Patients with blood-culture-confirmed typhoid fever and healthy control subjects were genotyped for 6 polymorphic markers within and near NRAMP1 on chromosome 2q35. Four single base-pair polymorphisms (274 C/T, 469+14 G/C, 1465-85 G/A, and D543N), a (GT)(n) repeat in the promoter region of NRAMP1 and D2S1471, and a microsatellite marker approximately 130-kb downstream of NRAMP1 were examined. The allelic and genotypic frequencies for each polymorphism were compared in case patients and control subjects. No allelic association was identified between the NRAMP1 alleles and typhoid fever susceptibility. In addition, neither homozygotes nor heterozygotes for any NRAMP1 variants were at increased risk of typhoid fever.


Asunto(s)
Proteínas Portadoras/genética , Proteínas de Transporte de Catión , Inmunidad Innata , Macrófagos/química , Proteínas de la Membrana/genética , Polimorfismo Genético/fisiología , Fiebre Tifoidea/genética , Alelos , Predisposición Genética a la Enfermedad , Genotipo , Heterocigoto , Homocigoto , Humanos , Repeticiones de Microsatélite , Regiones Promotoras Genéticas/genética , Fiebre Tifoidea/inmunología , Vietnam
20.
Epilepsia ; 42(1): 29-40, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11207782

RESUMEN

PURPOSE: Vigabatrin (VGB) is a new antiepileptic drug that increases the human brain gamma-aminobutyric acid (GABA) level by irreversibly inhibiting GABA transaminase. Although some patients respond to VGB with a significant seizure reduction, others do not. The aim of this study was to identify possible responders before or in an early phase of VGB treatment by measuring the GABA and homocarnosine contaminated with macromolecules/creatine and phosphocreatine ratio (GABA+/Cr) signal by means of proton-nuclear magnetic resonance (1H NMR) spectroscopy. METHODS: Measurements were performed immediately before and after a titration period of 1 month (2 g/day during the past 2 weeks). A third measurement followed a maintenance period of 3 months (2 or 3 g/day). In 14 patients with drug-resistant temporal lobe epilepsy and 3 patients with occipital lobe epilepsy, GABA+/Cr was measured in the ipsilateral (i.e., epileptogenic) hemisphere and contralateral (i.e., nonepileptogenic) hemisphere in a volume of 8 cm3. RESULTS: Depending on the therapeutic efficacy of VGB, we defined three groups: (a) full responders (n = 7), (b) nonresponders (n = 7), and (c) partial responders (n = 3). The nonresponders had no significant change in the GABA+/Cr signal during the treatment compared with baseline. The full responders had a significant increase of the GABA+/Cr signal during the whole treatment phase and a lower ipsilateral level at baseline. The partial responders had also a lowered ipsilateral GABA+/Cr signal at baseline and an increase during treatment but a decrease when the seizures started again. CONCLUSIONS: Responders to VGB could be identified by a lower ipsilateral baseline GABA+/Cr signal and a steeper increase during VGB treatment. However, it was not possible to predict the duration of the response (full versus partial responder) with these criteria.


Asunto(s)
Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Química Encefálica/efectos de los fármacos , Creatina/análisis , Epilepsia/diagnóstico , Epilepsia/tratamiento farmacológico , Espectroscopía de Resonancia Magnética/métodos , Vigabatrin/farmacología , Vigabatrin/uso terapéutico , Ácido gamma-Aminobutírico/análisis , Adolescente , Adulto , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/fisiología , Química Encefálica/fisiología , Carnosina/análogos & derivados , Carnosina/análisis , Carnosina/química , Creatina/química , Epilepsia/metabolismo , Epilepsia del Lóbulo Temporal , Femenino , Lateralidad Funcional , Humanos , Espectroscopía de Resonancia Magnética/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Lóbulo Occipital/efectos de los fármacos , Lóbulo Occipital/fisiopatología , Fosfocreatina/análisis , Fosfocreatina/química , Resultado del Tratamiento , Ácido gamma-Aminobutírico/química
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