Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 60
Filtrar
1.
Brain Inj ; 23(13-14): 999-1007, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19891539

RESUMEN

OBJECTIVES: To evaluate the reliability and validity of the Apathy Evaluation Scale (AES) and Apathy sub-scale of the Frontal Systems Behavior Scale (FrSBe-A) for people with traumatic brain injury (TBI). To identify an optimal cut-off score indicating presence of apathy according to the AES. METHODS AND PROCEDURES: A sample of 34 participants with severe TBI currently residing in the community underwent neuropsychological and psychosocial assessment to evaluate reliability, discriminant, convergent and divergent validity. Receiver Operating Characteristic (ROC) curve analysis was undertaken to identify an optimal cut-off score on the AES. RESULTS: AES and FrSBe-A correlated moderately with each other (r = 0.71). Both AES and FrSBe-A have good internal consistency and discriminant validity with measures of depression and fatigue. Support for hypothesized correlations with similar and dissimilar constructs was not shown. ROC analysis identified a cut-off score of 37 or higher on AES indicated presence of apathy. CONCLUSIONS: AES and FrSBe-A are reliable and valid measures of apathy following TBI. It is suggested that the two scales measure slightly differing aspects of the apathy construct, with AES addressing emotional-affective aspects of apathy more than FrSBe-A, which focuses more heavily on cognitive and behavioral elements of goal-directed behavior.


Asunto(s)
Lesiones Encefálicas/psicología , Trastorno Depresivo/psicología , Escalas de Valoración Psiquiátrica , Adolescente , Adulto , Lesiones Encefálicas/diagnóstico , Lesiones Encefálicas/fisiopatología , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Curva ROC , Valores de Referencia , Reproducibilidad de los Resultados , Adulto Joven
2.
Neuropsychol Rehabil ; 19(4): 481-516, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19533496

RESUMEN

Apathy commonly occurs after acquired brain impairment. It is characterised by impaired initiative, diminished activity, and lack of concern; formally delineated as a decrease in cognitive, behavioural and emotional components of goal-directed activity. The impact is widespread, hampering rehabilitation and outcome. This systematic review identifies and assesses the efficacy of non-pharmacological treatments for apathy following four types of acquired brain impairment (traumatic brain injury, dementia, cerebrovascular accident, encephalitis). Nine databases were searched. Studies were reviewed according to the following criteria: age over 16 years, acquired brain impairment, non-pharmacological intervention for apathy, and data reported on treatment efficacy. The methodological quality of the studies was assessed. Searches yielded 1754 articles, with 28 meeting criteria. Methodological quality ranged greatly. The majority of trials involved the dementia population. Cognitive interventions were the most frequent mode of treatment. For those with severe impairments, the strongest evidence suggested music therapy and for milder impairment, the strongest evidence was for cognitive rehabilitation. This review reveals a need for more high quality, methodologically rigorous treatment studies for apathy, particularly within the milder ranges of impairment. Initially, however, a uniform operational definition needs to be utilised in all research studies to minimise variability. Additionally, employing a standardised outcome measure specific to apathy would greatly enhance comparison among treatments.


Asunto(s)
Encefalopatías/complicaciones , Trastornos del Humor/complicaciones , Trastornos del Humor/terapia , Humanos , Factores de Tiempo
3.
Nat Commun ; 9(1): 4190, 2018 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-30305618

RESUMEN

How a single bacterium becomes a colony of many thousand cells is important in biomedicine and food safety. Much is known about the molecular and genetic bases of this process, but less about the underlying physical mechanisms. Here we study the growth of single-layer micro-colonies of rod-shaped Escherichia coli bacteria confined to just under the surface of soft agarose by a glass slide. Analysing this system as a liquid crystal, we find that growth-induced activity fragments the colony into microdomains of well-defined size, whilst the associated flow orients it tangentially at the boundary. Topological defect pairs with charges [Formula: see text] are produced at a constant rate, with the [Formula: see text] defects being propelled to the periphery. Theoretical modelling suggests that these phenomena have different physical origins from similar observations in other extensile active nematics, and a growing bacterial colony belongs to a new universality class, with features reminiscent of the expanding universe.


Asunto(s)
Escherichia coli/crecimiento & desarrollo , Modelos Biológicos , Recuento de Colonia Microbiana , Simulación por Computador , Estrés Fisiológico
4.
J Neurol Neurosurg Psychiatry ; 77(7): 841-9, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16574735

RESUMEN

BACKGROUND: Post-traumatic amnesia (PTA) tests that record different PTA durations in the same patient, thereby raising measurement accuracy issues, have been reported previously. A major problem lies in determining the end point of PTA. AIMS: To delineate areas of discrepancy in PTA tests and to provide independent verification for a criterion signalling emergence from PTA. METHODS: In a randomised design, two related PTA procedures were compared, one purportedly more difficult (Westmead PTA Scale, WPTAS) than the other (Modified Oxford PTA Scale, MOPTAS). Eighty two patients in the early stages of PTA were examined daily until emergence, by using the Galveston Orientation and Amnesia Test (GOAT) and the WPTAS/MOPTAS. A short battery of cognitive and behavioural measurements was made on three occasions: at the early stage of PTA (time 1), towards the end of PTA when the maximum score (12/12) was first obtained (time 2) and at the traditional criterion for emergence (scoring 12/12 for 3 consecutive days; time 3). RESULTS: No significant difference was recorded in PTA duration between the MOPTAS and WPTAS. Both scales recorded longer PTA durations than the GOAT. By using Kaplan-Meier survival analyses, the WPTAS was found to show a more protracted pattern of emergence at the end stage of PTA than the MOPTAS. A time lag of > or = 1 week in the resolution of disorientation as compared with amnesia was observed in 59% cases. Significant improvements occurred on all independent measurements between time 1 and time 2, but on only 2 of 5 cognitive measurements between time 2 and time 3. CONCLUSIONS: Although no significant differences in the duration of PTA on the MOPTAS/WPTAS were recorded, emergence from the late stages of PTA occurred more promptly with the MOPTAS. The need for inclusion of both orientation and memory items in PTA tests is highlighted by the frequency of disorientation-amnesia dissociations. The patterns of results on the independent measures suggest that patients who are in PTA for > 4 weeks have probably emerged from PTA when they first score 12/12 on the MOPTAS/WPTAS, and this criterion can replace the traditional criterion.


Asunto(s)
Amnesia/diagnóstico , Amnesia/etiología , Pruebas Psicológicas/normas , Trastornos por Estrés Postraumático/complicaciones , Adolescente , Adulto , Anciano , Determinación de Punto Final , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Reconocimiento en Psicología , Reproducibilidad de los Resultados
5.
Diabetes ; 38(4): 428-34, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2925006

RESUMEN

In these studies, we examined the effect of excess levels of growth hormone (GH) on rat insulinlike growth factor I (IGF-I) gene expression in streptozocin-induced diabetes mellitus. A solution hybridization/RNase protection assay was used to simultaneously quantitate the relative tissue content of the variant IGF-I mRNA species arising from alternative splicing in the region encoding the COOH-terminal extension E-peptide (IGF-Ia and IGF-Ib). IGF-Ia and IGF-Ib mRNAs were markedly decreased in liver, kidney, and lung tissues of diabetic rats. Although GF stimulates IGF-I gene expression, chronic GH excess from implanted somatomammotropic tumors did not appropriately induce tissue IGF-I mRNA content in diabetic animals. Treatment of diabetic rats with insulin for 1 wk restored basal and GH-stimulated IGF-Ia and IGF-Ib mRNA content toward that present in tissues of nondiabetic rats. The ratio of IGF-Ia to IGF-Ib mRNA remained relatively constant for each tissue and was not affected by the diabetic state, chronic GH hyperstimulation, or insulin therapy, suggesting that posttranscriptional splicing is not a regulated event in these conditions. Thus, both circulating IGF-I levels and tissue IGF-I gene expression are profoundly decreased in this model of experimental diabetes. Diminished tissue availability of IGF-I from endocrine and/or paracrine sources may be responsible for the growth retardation seen in uncontrolled diabetes mellitus.


Asunto(s)
Diabetes Mellitus Experimental/genética , Factor I del Crecimiento Similar a la Insulina/genética , Neoplasias Hipofisarias/genética , Procesamiento Postranscripcional del ARN , ARN Mensajero/genética , Somatomedinas/genética , Transcripción Genética , Animales , Glucemia/análisis , Línea Celular , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Femenino , Hormona del Crecimiento/sangre , Hormona del Crecimiento/metabolismo , Factor I del Crecimiento Similar a la Insulina/sangre , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/metabolismo , Ratas , Ratas Endogámicas WF , Valores de Referencia
6.
Artículo en Inglés | MEDLINE | ID: mdl-26465474

RESUMEN

We demonstrate that the formation of bicontinuous emulsions stabilized by interfacial particles (bijels) is more robust when nanoparticles rather than microparticles are used. Emulsification via spinodal demixing in the presence of nearly neutrally wetting particles is induced by rapid heating. Using confocal microscopy, we show that nanospheres allow successful bijel formation at heating rates two orders of magnitude slower than is possible with microspheres. In order to explain our results, we introduce the concept of mechanical leeway, i.e., nanoparticles benefit from a smaller driving force towards disruptive curvature. Finally, we suggest that leeway mechanisms may benefit any formulation in which challenges arise due to tight restrictions on a pivotal parameter, but where the restrictions can be relaxed by rationally changing the value of a more accessible parameter.

7.
Magn Reson Imaging ; 33(2): 236-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25460332

RESUMEN

BACKGROUND: Dodecafluoropentane emulsion (DDFPe), an oxygen transport agent, has been shown to reduce infarct volume in animal models of acute ischemic stroke (AIS). Our study assesses the effect of DDFPe on MRI markers of infarct evolution in the early hours after vascular occlusion in a rat AIS model. We hypothesized that DDFPe will delay the development of MRI markers of AIS and/or reduce the extent of infarction. METHODS: Permanent, unilateral surgical occlusion of the middle cerebral and common carotid arteries was performed in control (n=4) and treatment (n = 10) rats. The treatment group received 1 IV dose of 2% w/v DDFPe at 0.6 mL/kg at 1 hour post-occlusion versus none. Diffusion-weighted (DWI) and inversion recovery (IR) MRI sequences were obtained over the 4 hours following occlusion. Infarct extent was quantified by number of abnormal MRI slices per sequence for each group and time point. Student's T-test was applied. RESULTS: DDFPe-treated rats demonstrated reduced infarct extent versus controls over combined time points on IR at 5.43 ± 0.40 (mean ± standard error) abnormal slices vs. 7.38 ± 0.58 (P = 0.01) and on DWI at 5.21 ± 0.54 vs. 9.00 ± 0.95 (P < 0.01). Development of abnormal MRI signal was delayed in the treatment group. CONCLUSIONS: DDFPe delays and reduces MRI markers of AIS in the early hours following vascular occlusion in a rat stroke model. Further investigation of DDFPe as a neuroprotectant is warranted.


Asunto(s)
Emulsiones , Fluorocarburos/administración & dosificación , Imagen por Resonancia Magnética , Accidente Cerebrovascular/fisiopatología , Animales , Infarto Encefálico/patología , Isquemia Encefálica/patología , Arteria Carótida Común/patología , Modelos Animales de Enfermedad , Masculino , Arteria Cerebral Media/patología , Fármacos Neuroprotectores/química , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/tratamiento farmacológico
8.
Mol Neurobiol ; 52(2): 979-84, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26055229

RESUMEN

Dodecafluoropentane emulsion (DDFPe) nanodroplets are exceptional oxygen transporters and can protect ischemic brain in stroke models 24 h without reperfusion. Current stroke therapy usually fails to reach patients because of delays following stroke onset. We tested using DDFPe to extend the time window for tissue plasminogen activator (tPA). Longer treatment windows will allow more patients more complete stroke recovery. We test DDFPe to safely extend the time window for tPA thrombolysis to 9 h after stroke. With IACUC approval, randomized New Zealand white rabbits (3.4-4.7 kg, n = 30) received angiography and 4-mm blood clot in the internal carotid artery for flow-directed middle cerebral artery occlusion. Seven failed and were discarded. Groups were IV tPA (n = 11), DDFPe + tPA (n = 7), and no therapy controls (n = 5). DDFPe (0.3 ml/kg, 2 % emulsion) IV dosing began at 1 h and continued at 90 min intervals for 6 doses in one test group; the other received saline injections. Both got standard IV tPA (0.9 mg/kg) therapy starting 9 h post stroke. At 24 h, neurological assessment scores (NAS, 0-18) were determined. Following brain removal percent stroke volume (%SV) was measured. Outcomes were compared with Kruskal-Wallis analysis. For NAS, DDFPe + tPA was improved overall, p = 0.0015, and vs. tPA alone, p = 0.0052. For %SV, DDFPe + tPA was improved overall, p = 0.0003 and vs. tPA alone, p = 0.0018. NAS controls and tPA alone were not different but %SV was, p = 0.0078. With delayed reperfusion, DDFPe + tPA was more effective than tPA alone in preserving functioning brain after stroke. DDFPe significantly extends the time window for tPA therapy.


Asunto(s)
Fibrinolíticos/uso terapéutico , Fluorocarburos/uso terapéutico , Infarto de la Arteria Cerebral Anterior/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/uso terapéutico , Animales , Hemorragia Cerebral/inducido químicamente , Modelos Animales de Enfermedad , Esquema de Medicación , Evaluación Preclínica de Medicamentos , Emulsiones , Femenino , Fibrinolíticos/administración & dosificación , Fibrinolíticos/toxicidad , Fluorocarburos/administración & dosificación , Infarto de la Arteria Cerebral Anterior/patología , Infarto de la Arteria Cerebral Media/patología , Infusiones Intravenosas , Masculino , Fármacos Neuroprotectores/administración & dosificación , Conejos , Distribución Aleatoria , Daño por Reperfusión/prevención & control , Método Simple Ciego , Terapia Trombolítica/efectos adversos , Factores de Tiempo , Activador de Tejido Plasminógeno/administración & dosificación , Activador de Tejido Plasminógeno/toxicidad
9.
Clin Pharmacol Ther ; 55(4): 464-70, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8162673

RESUMEN

The definition and detection of the onset of analgesic drug activity represent two of the more complicated methodologic challenges in clinical pharmacology. We addressed these issues by designing an analgesic assay with frequent posttreatment assessments to identify the first time when a subject experienced relief and when a nonprescription-strength analgesic could be distinguished from placebo. To test the feasibility of conducting this assay, 29 subjects with acute sore throat were randomized to receive 200 mg ibuprofen, 400 mg ibuprofen, or placebo under double-blind conditions. To identify the onset of analgesia, subjects used three rating scales at 5-minute intervals over the first hour. Subjects completed each series of assessments efficiently, most within 5 seconds. Each active agent was differentiated from placebo early after treatment (p < or = 0.05), and there was dose-separation. We conclude that the sore throat pain model can be used to evaluate the onset of action of nonprescription-strength analgesic agents.


Asunto(s)
Ibuprofeno/uso terapéutico , Faringitis/tratamiento farmacológico , Administración Oral , Adolescente , Adulto , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Ibuprofeno/administración & dosificación , Ibuprofeno/farmacología , Masculino , Proyectos Piloto , Factores de Tiempo
10.
Atherosclerosis ; 158(1): 129-38, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11500183

RESUMEN

PURPOSE: The role that homocysteine may play in post-carotid endarterectomy (CEA) restenosis due to intimal hyperplasia is not well understood. This study was designed to investigate the effects of different levels of dietary homocystine on: (1) plasma homocysteine; (2) post-CEA intimal hyperplasia; and (3) levels of the methyl donor S-adenosylmethionine (SAM) and its counterpart S-adenosylhomocysteine (SAH) in the homocysteine pathway. METHODS: Male rats were fed specialized diets for 2 weeks pre- and post-CEA. Groups included control (0 homocystine added, n=9), 1.5 (1.5 g/kg homocystine added, n=10), 3.0 (3.0 g/kg homocystine added, n=9), and 4.5 (4.5 g/kg homocystine added, n=11). The rats underwent a surgical carotid endarterectomy. Endpoints included; plasma homocysteine, intimal hyperplasia, replicative index using with alpha-SM actin and BrdU, hepatic SAM levels, SAH levels, and the hepatic activities of methylenetetrahydrofolate reductase (MTHFR) and cystathionine beta-synthase (CBS). RESULTS: Increasing dietary homocystine produced a proportionate increase in plasma homocysteine and an increase in intimal hyperplasia. Regression analysis of plasma homocysteine levels and intimal hyperplasia showed a significant correlation (r=0.71,P=0.003). Plasma homocysteine levels above 15 microM were associated with significant increases in intimal hyperplasia above 6.5% (P=0.04). Elevation of plasma homocysteine levels to moderate levels (5-25 microM) resulted in significant post-CEA intimal hyperplasia. Cellular analysis of the area of intimal hyperplasia in all diet groups showed comparable amounts of cells positive for alpha-SM actin. However, with increasing levels of dietary homocystine and plasma homocysteine there was an increase in replicative index (P<0.001) as determined by BrdU staining. Increasing dietary homocystine increased plasma homocysteine and was followed by increases in the replicative index thus producing increased intimal hyperplasia and lumenal stenosis. In hepatic measurements the 1.5 and 3.0 g/kg homocystine diets caused: increased liver activity of MTHFR (P=0.03) and decreased hepatic levels of SAM, SAH and SAM/SAH ratios compared to controls. Homocystine treatment did not cause significant alterations in CBS levels (P=0.992). These studies also showed no correlation of the MTHFR and CBS enzymes with plasma homocysteine levels or intimal hyperplasia. However, hepatic levels of SAM showed significant negative correlations with plasma homocysteine (r=-0.58; P=0.006) and with BrdU percentages of cellular proliferation (r=-0.69; P=0.06). CONCLUSION: The degree of post-CEA intimal hyperplasia in a rat model is directly related to the plasma level of homocysteine. The hyperplastic effects of homocysteine may be mediated in part by a physiological insufficiency of methyl donors as shown by decreases in SAM. Thus, increasing levels of plasma homocysteine enhanced and accelerated the smooth muscle cell response after CEA which led to increased intimal hyperplasia and lumenal stenosis.


Asunto(s)
Arterias Carótidas/patología , Endarterectomía Carotidea , Homocisteína/sangre , Homocistina/administración & dosificación , Túnica Íntima/patología , Animales , Cistationina betasintasa/metabolismo , Hiperplasia , Hígado/enzimología , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2) , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/metabolismo , Ratas , Ratas Sprague-Dawley , Recurrencia , S-Adenosilhomocisteína/metabolismo , S-Adenosilmetionina/metabolismo
11.
Bone Marrow Transplant ; 3(5): 483-93, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3056555

RESUMEN

Conditioning chemoradiotherapy damages the mucosal barrier of the mouth and throat and often produces severe oral inflammation and infection. In a prospective, double-blind, randomized study, we examined the use of a chlorhexidine digluconate mouthrinse for prophylaxis against oral mucosal complications in 51 bone marrow transplant patients. Use of chlorhexidine mouthrinse produced significant reductions in the incidence and severity of oral mucositis. Mucositis also resolved more quickly in patients receiving chlorhexidine. Concomitant reductions in total oral streptococci (p less than 0.02-p less than 0.001) and oral candida (p less than 0.004) were seen in patients using chlorhexidine. Persistent clinical oral candidiasis (thrush) was observed in 15 to 27 control group patients (56%), but only transiently in two (8%) of 24 patients who used chlorhexidine rinse (p less than 0.001). Five of 27 control group patients (19%) had candidemia, while no candidemia was observed in the chlorhexidine group (p less than 0.03). Three deaths from disseminated candidiasis occurred in the placebo group; none occurred in patients who received chlorhexidine. Prophylactic use of chlorhexidine mouthrinse produces reductions in oral soft tissue disease and oral microbial burden in patients undergoing bone marrow transplantation. The reductions in mucositis and in oral candida infections observed with prophylactic chlorhexidine mouthrinse represent a significant advantage for patients undergoing marrow transplantation.


Asunto(s)
Trasplante de Médula Ósea , Candidiasis Bucal/prevención & control , Clorhexidina/análogos & derivados , Estomatitis/prevención & control , Adolescente , Adulto , Infecciones Bacterianas/prevención & control , Niño , Preescolar , Clorhexidina/uso terapéutico , Ensayos Clínicos como Asunto , Método Doble Ciego , Bacterias Aerobias Gramnegativas , Humanos , Lactante , Persona de Mediana Edad , Mucosa Bucal/microbiología , Estudios Prospectivos , Infecciones Estreptocócicas/prevención & control
12.
Metabolism ; 50(9): 1014-8, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11555831

RESUMEN

The erythrocyte concentrations of the body's chief physiologic methyl donor S-adenosylmethionine (SAM) and of its metabolite and inhibitor S-adenosylhomocysteine (SAH), the plasma concentrations of total homocysteine (tHcy), and the activity of N(5,10) methylenetetrahydrofolate reductase (MTHFR) in lymphocytes were determined in healthy subjects and patients with diabetes mellitus without complications and at various stages of diabetic nephropathy, categorized according to the degree of progression of the disease. These groups were as follows: 1, control; 2, diabetics with no complications; 3, patients with albuminuria; 4, patients with an elevated plasma creatinine; and 5, patients on dialysis. No parameter studied exhibited significant differences between the type 1 and the type 2 diabetics. In control subjects, the blood concentrations of SAM were proportional to the activity of MTHFR; in diabetics, it was not. Consistent with previous observations, progression of nephropathy was accompanied by increased concentrations of tHcy. Increased erythrocyte concentrations of SAH, decreased erythrocyte concentrations of SAM, SAM/SAH ratios, and lymphocyte MTHFR activity also accompanied disease progression. The blood concentrations of SAH paralleled those of tHcy, while the concentrations of SAM showed a bimodal relationship with those of tHcy. These results provide further evidence that alterations in the blood concentrations of SAM and related compounds are abnormal in patients with diabetes, particularly in those with nephropathy. The deficiency of SAM may lead to methyl deficiencies, which may contribute to the high morbidity and mortality in patients with diabetic nephropathy. We have also demonstrated a decrease in lymphocyte MTHFR activity in patients with advanced nephropathy, suggesting that hyperhomocysteinemia in these patients may be due to a generalized metabolic abnormality. Further studies are needed to determine the pathogenesis of these abnormalities and whether they are present in renal failure due to causes other than diabetes or whether they are specific to diabetic nephropathy.


Asunto(s)
Diabetes Mellitus/metabolismo , Nefropatías Diabéticas/metabolismo , Linfocitos/enzimología , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/metabolismo , S-Adenosilmetionina/sangre , Adulto , Albuminuria , Creatinina/sangre , Complicaciones de la Diabetes , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/terapia , Progresión de la Enfermedad , Eritrocitos/metabolismo , Femenino , Homocisteína/sangre , Humanos , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2) , Persona de Mediana Edad , Valores de Referencia , Análisis de Regresión , Diálisis Renal , S-Adenosilhomocisteína/sangre
13.
J Dent Res ; 68(7): 1199-204, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2632605

RESUMEN

Fifteen bone marrow transplant (BMT) patients who received three 0.12% chlorhexidine digluconate (CHX) mouthrinses daily for eight weeks were monitored weekly for the occurrence of oral opportunistic Gram-negative bacilli (GNB). Tongue and buccal mucosa were sampled with use of Culturette swabs that were streaked on plates containing selective MacConkey agar. After incubation, colony-forming units were scored and putative GNB classified with use of the API 20E rapid identification system and supplemental biochemical tests. After identification, the susceptibilities of all GNB to CHX were determined by means of a disk diffusion sensitivity assay. Sixty-seven percent (10) of the BMT subjects had at least one GNB-positive tongue culture, and 53% (8) had GNB in samples taken from the buccal mucosa. Of 218 samples taken, 26% and 24% from the tongue and buccal mucosa, respectively, were GNB-positive. The predominant clinical GNB isolates were Enterobacter cloacae (46%) and Klebsiella pneumoniac (30%). Their respective CHX minimum inhibitory concentrations (MICs) were similar to those of ATCC reference strains. Although the CHX MIC values of the clinical GNB isolates were high (less than or equal to 37.5 to less than or equal to 300 micrograms/mL), they were not dependent upon length of exposure to the agent. Therefore, changes in sensitivity or resistance to CHX did not appear to occur. The results suggest that the mouths of BMT patients--and perhaps of other immunosuppressed individuals--should be routinely monitored for GNB, as are other clinically important sites, such as the throat and the urinary and gastro-intestinal tracts.


Asunto(s)
Trasplante de Médula Ósea , Clorhexidina/análogos & derivados , Bacterias Gramnegativas/aislamiento & purificación , Boca/microbiología , Adolescente , Adulto , Bacillus/efectos de los fármacos , Bacillus/aislamiento & purificación , Niño , Clorhexidina/uso terapéutico , Recuento de Colonia Microbiana , Femenino , Bacterias Gramnegativas/efectos de los fármacos , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Antisépticos Bucales/uso terapéutico
14.
J Periodontol ; 62(10): 617-22, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1770421

RESUMEN

The purpose of this study was to test the efficacy and safety of sanguinaria-containing regimens with and without fluoride using the American Dental Association guidelines for evaluating chemotherapeutic agents. The study was a 6-month, double-blind, 4-cell, placebo-controlled, parallel investigation involving 120 subjects. Following screening procedures, subjects were randomly assigned to 4 groups. Group 1 received a dentifrice containing 0.075% sanguinaria extract (SaE) and 2.0% zinc chloride (ZnCl2) in a dicalcium phosphate base, plus an oral rinse containing 0.03% SaE and 0.2% ZnCl2. Group 2 received identical products without SaE or ZnCl2. Group 3 received a dentifrice containing 0.8% sodium monofluorophosphate, 0.075% SaE, and 0.05% ZnCl2 in a silica base, plus an oral rinse containing 0.03% SaE and 0.2% ZnCl2. Group 4 products were identical to those of Group 3 but without SaE and ZnCl2. Supragingival plaque and gingival inflammation were scored at 0, 1, 2, 1.5, 3, 4.5, and 6 months; bleeding upon probing was measured at 1, 1.5, 3, and 6 months. Microbiological samples were taken from plaque, tongue, and cheek areas. The active products produced statistically significantly lower scores than the placebo agents for all indices (P less than .0001). Six-month plaque scores were 13.1% lower for Group 1 and 17.4% lower for Group 3 compared to placebo products. When the Plaque Severity Index was applied, the percentage reductions were 33% for Group 1 and 41% for Group 3 compared to placebos. Gingival inflammation scores were 16.7% lower for Group 1 and 18.1% lower for Group 3 at 6 months compared to placebo scores.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Alcaloides/uso terapéutico , Antibacterianos/uso terapéutico , Placa Dental/prevención & control , Dentífricos/uso terapéutico , Fluoruros/uso terapéutico , Gingivitis/prevención & control , Antisépticos Bucales/uso terapéutico , Adulto , Alcaloides/administración & dosificación , Antibacterianos/administración & dosificación , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Benzofenantridinas , Recuento de Colonia Microbiana , Placa Dental/microbiología , Índice de Placa Dental , Método Doble Ciego , Combinación de Medicamentos , Femenino , Fluoruros/administración & dosificación , Hemorragia Gingival/prevención & control , Humanos , Isoquinolinas , Masculino , Índice Periodontal , Placebos
15.
Arch Oral Biol ; 28(4): 327-38, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6576737

RESUMEN

Capnocytophaga ochracea strain 25 was originally isolated from a patient with severe juvenile periodontitis. An NAD-specific glutamate dehydrogenase (GDH) (EC 1.4.1.2.) was found in cell-free extracts from this organism. The NADH-dependent reductive, or ammonia-assimilating activity (NADH-GDH), of the enzyme was 8-10-fold higher than its NAD-dependent oxidative, or ammonia-releasing activity (NAD-GDH), suggesting that the primary physiological role of the GDH is ammonia-fixing. Capnocytophaga ochracea GDH was purified approximately 39-fold by a rapid, single-step purification procedure using DEAE-cellulose (DE52) ion-exchange column chromatography which gave 90 per cent recovery of total enzyme units. Paper chromatography of an NADH-GDH assay mixture containing the partially purified enzyme showed that glutamate was, indeed, a product of the ammonia-assimilating reaction. The pH optimum for the NAD-GDH reaction was 9.0; that for the NADH-GDH reaction was 7.5. Although a number of mono- and divalent cations were tested, none had a large effect on either NAD-GDH or NADH-GDH activity. The NAD-GDH reaction showed a hyperbolic kinetic response to glutamate and NAD and the Km values for glutamate and NAD were 2.44 and 0.083 mM respectively. The kinetic response of the NADH-GDH reaction to NADH, alpha-ketoglutarate and ammonium chloride also obeyed Michaelis-Menten kinetics and their respective Km values were 0.069, 1.44 and 3.33 mM. Of a number of biologically-active compounds tested for their ability to modulate GDH activity, only ADP and NAD exerted much effect. The NADH-GDH activity showed a negative hyperbolic kinetic response to both ADP and NAD and Dixon plot-analysis of the NAD and ADP saturation data gave Ki values for ADP and NAD of 4.0 and 0.46 mM respectively. Both NAD and ADP appeared to exert their negative effects on NADH-GDH activity by completely inhibiting the binding of the reduced coenzyme, NADH, to the enzyme.


Asunto(s)
Amoníaco/metabolismo , Capnocytophaga/metabolismo , Cytophagaceae/metabolismo , Infecciones Bacterianas , Glutamato Deshidrogenasa/aislamiento & purificación , Glutamato Deshidrogenasa/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Cinética , NAD , Periodontitis/etiología , Especificidad por Sustrato
16.
Community Dent Oral Epidemiol ; 12(5): 325-31, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6386307

RESUMEN

Two simple microbiological tests for quantitating salivary Streptococcus mutans levels were compared with each other and evaluated for suitability for mass screenings and private practice. Both tests use mitis salivarius medium with bacitracin (MSB) and are selective for S. mutans. One test estimates colonies grown on agar (MSBA) and the other estimates colonies grown in broth that adhere to glass (MSBB). Both are scored from 1 (lowest) to 5 (highest). Children (293) in grades 5 and 6 in Tallahassee, Florida (nonfluoridated) were tested for S. mutans levels. Scores of children by both tests were significantly similar (chi 2, regression and Kappa statistical analysis). Correlation coefficients (regression) between scores and DMFS increments of the previous 4 yr were 0.35 (MSBA) and 0.26 (MSBB). Both tests were very good in identifying children with low caries increments, but positive scores did not correlate well with high caries increments. Sampling and interpreting took 2 min (MSBA) and 1 min (MSBB). Cost of MSBA/child was $1.15, and MSBB/child $1.25. These tests are economical and suitable for mass screenings to identify low risk populations who do not require preventive treatment.


Asunto(s)
Susceptibilidad a Caries Dentarias , Tamizaje Masivo/métodos , Streptococcus mutans/aislamiento & purificación , Técnicas Bacteriológicas , Niño , Índice CPO , Pruebas de Actividad de Caries Dental/métodos , Florida , Humanos , Tamizaje Masivo/economía , Saliva/microbiología , Población Urbana
17.
Oncol Nurs Forum ; 21(4): 691-6, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8047467

RESUMEN

PURPOSE/OBJECTIVES: To examine whether use of chlorhexidine (CHX) in stomatitis-prevention regimens following bone marrow transplantation (BMT) enhances the emergence of gram-negative bacilli (GNB) to a degree that exceeds its benefits. DATA SOURCES: Articles, book chapters, and case studies. DATA SYNTHESIS: Despite rigorous topical and systemic antimicrobial therapy, oral opportunistic GNB infections occur following BMT. This is most likely because of low susceptibility of GNB to CHX and not that CHX predisposes patients to these infections or the development of CHX resistant strains. CONCLUSIONS: The benefits of CHX use (e.g. preservation of oral mucosa and broad-spectrum antibacterial and antifungal effects) outweight the risks of GNB infection. IMPLICATIONS FOR NURSING PRACTICE: Routine clinical and microbiologic monitoring of the oral cavity are essential with use of CHX. Stomatitis care standards and patient instructions following discharge are included.


Asunto(s)
Trasplante de Médula Ósea , Clorhexidina/efectos adversos , Bacterias Gramnegativas/aislamiento & purificación , Boca/microbiología , Estomatitis/prevención & control , Adulto , Clorhexidina/uso terapéutico , Humanos , Huésped Inmunocomprometido , Leucemia/terapia , Masculino , Persona de Mediana Edad , Higiene Bucal
18.
J Am Dent Assoc ; 114(4): 461-7, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3549834

RESUMEN

Intensive chemoradiotherapy damages the mucosal barrier of the mouth and throat and is often associated with severe oral inflammation and infection. This study examined the use of a 0.12% chlorhexidine gluconate mouthrinse for prophylaxis against oral complications in patients receiving bone marrow transplants. Use of chlorhexidine mouthrinse produced reductions in oral soft tissue disease and oral microbial burden, including a significant decrease in oral mucositis and Candida infections. The advantage for patients undergoing intensive antineoplastic therapy, and potentially for other immunocompromised patients susceptible to oral infections, was studied.


Asunto(s)
Trasplante de Médula Ósea , Clorhexidina/uso terapéutico , Enfermedades de la Boca/prevención & control , Adolescente , Adulto , Candidiasis Bucal/prevención & control , Niño , Preescolar , Clorhexidina/administración & dosificación , Placa Dental/prevención & control , Método Doble Ciego , Gingivitis/prevención & control , Humanos , Terapia de Inmunosupresión , Persona de Mediana Edad , Antisépticos Bucales , Estudios Prospectivos , Distribución Aleatoria , Estomatitis/prevención & control , Streptococcus/efectos de los fármacos , Streptococcus/aislamiento & purificación
19.
J Dent Educ ; 46(6): 314-22, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6953130

RESUMEN

This article presents a critical analysis of the ten-year experience of the Department of Oral Biology of the University of Kentucky College of Dentistry with a nontraditional basic science curriculum. The factors that led to the adoption of this curriculum are outlined, and its effects on students, faculty, and the college's administration are described. The pitfalls inherent in this approach and in the individualized self-instructional format for teaching the basic sciences to dental students are discussed. This critical evaluation is aimed at providing information for those contemplating similar sweeping curricular changes in the future to enable them to make rational decisions and to help them predict the effects of such changes on the educational program.


Asunto(s)
Curriculum , Educación en Odontología , Ciencia , Enseñanza/métodos , Evaluación Educacional , Docentes de Odontología , Humanos , Relaciones Interpersonales , Kentucky , Estudiantes de Odontología
20.
Aust Vet J ; 77(6): 388-91, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10812406

RESUMEN

OBJECTIVE: To compare the ability of a new single-dose botulinum vaccine containing a non-mineral oil adjuvant with a single dose of a conventional botulinum vaccine product to produce antibody to Clostridium botulinum types C and D in cattle in Northern Australia. DESIGN AND PROCEDURE: One hundred and fifty Brahman steer weaners were randomly divided into two groups receiving either a single dose of CSL Bivalent Botulinum vaccine or Websters Singvac. Blood samples were collected at 0, 8 and 24 weeks and tested by antibody ELISA. The final samples were also tested by the toxin neutralisation test, to test titres of neutralising antibody. RESULTS: Six months after inoculation, cattle vaccinated with Websters Singvac had ELISA antibody response twice that of CSL conventional product. However, this difference was only evident for neutralising antibody to type C botulinum toxin. Both products produced similar titres of type D neutralising antibody after a single dose. CONCLUSION: Websters' Singvac produces a greater neutralising antibody response to type C botulism upon single inoculation than a conventional vaccine. The product produces an equivalent neutralising antibody response to type D.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Vacunas Bacterianas/inmunología , Botulismo/veterinaria , Enfermedades de los Bovinos/inmunología , Clostridium botulinum/inmunología , Animales , Botulismo/inmunología , Botulismo/prevención & control , Bovinos , Enfermedades de los Bovinos/prevención & control , Ensayo de Inmunoadsorción Enzimática/veterinaria , Masculino
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda