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1.
Rev. mex. ing. bioméd ; 42(1): e1110, Jan.-Apr. 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1156801

ABSTRACT

ABSTRACT A new coronavirus denominated first 2019-nCoV and later SARS-CoV-2 was found in Wuhan, China in December of 2019. This paper compares three mathematical methods: nonlinear regression, SIR, and SEIR epidemic models, to track the covid-19 disease in nine countries affected by the SARS-CoV-2 virus, to help epidemiologists to know the disease trajectory, considering initial data in the pandemic, mainly 100 days from the beginning. To evaluate the results obtained with the three methods one-way ANOVA is applied. The average of predicted infected cases with SARS-CoV-2, obtained with the mentioned methods was: for United States of America 1,098,508, followed by Spain with 226,721, Italy with 202,953, France with 183,897 United Kingdom with 182,190, Germany with 159,407, Canada with 58,696, Mexico with 50,366 and Argentina with 4,860 in average. The one-way ANOVA does not show a significant difference among the results of the projected infected cases by SARS-CoV-2, using nonlinear regression, SIR, and SEIR epidemic methods. The above could mean that initially any method can be used to model the pandemic course.


RESUMEN Un nuevo coronavirus denominado primero 2019-nCoV y más tarde SARS-CoV-2 fue encontrado en Wuhan, China en diciembre de 2019. El objetivo de este trabajo es comparar tres métodos matemáticos: regresión no lineal, modelos epidemiológicos SIR y SEIR, para rastrear la enfermedad del COVID-19 en nueve países infectados por el virus SARS-CoV-2, con el propósito de ayudar al epidemiólogo a conocer el curso de la pandemia, considerando principalmente sus primeros 100 días. Para evaluar los resultados obtenidos de la aplicación de los tres métodos, se aplicó ANOVA de una vía. El número promedio de casos infectados con SARS-CoV-2, obtenidos con los tres métodos descritos son: para Estados Unidos 1,098,508, seguido de España con 226,721, Italia con 202,953, Francia con 183,897 Reino Unido con 182,190, Alemania con 159,407, Canadá con 58,696, México con 50,366 y Argentina con 4,860 en promedio. El ANOVA de una vía no muestra diferencias significativas entre los resultados de los casos infectados proyectados por SARS-CoV-2, utilizando la regresión no lineal y los métodos SIR and SEIR. Lo anterior podría señalar que cualquiera de los tres métodos estudiados puede modelar el curso de la pandemia en las condiciones descritas para cada uno.

2.
Mol Psychiatry ; 20(10): 1161-72, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26260494

ABSTRACT

Alterations in glutamatergic transmission onto developing GABAergic systems, in particular onto parvalbumin-positive (Pv(+)) fast-spiking interneurons, have been proposed as underlying causes of several neurodevelopmental disorders, including schizophrenia and autism. Excitatory glutamatergic transmission, through ionotropic and metabotropic glutamate receptors, is necessary for the correct postnatal development of the Pv(+) GABAergic network. We generated mutant mice in which the metabotropic glutamate receptor 5 (mGluR5) was specifically ablated from Pv(+) interneurons postnatally, and investigated the consequences of such a manipulation at the cellular, network and systems levels. Deletion of mGluR5 from Pv(+) interneurons resulted in reduced numbers of Pv(+) neurons and decreased inhibitory currents, as well as alterations in event-related potentials and brain oscillatory activity. These cellular and sensory changes translated into domain-specific memory deficits and increased compulsive-like behaviors, abnormal sensorimotor gating and altered responsiveness to stimulant agents. Our findings suggest a fundamental role for mGluR5 in the development of Pv(+) neurons and show that alterations in this system can produce broad-spectrum alterations in brain network activity and behavior that are relevant to neurodevelopmental disorders.


Subject(s)
Interneurons/metabolism , Interneurons/pathology , Neurodevelopmental Disorders/metabolism , Neurodevelopmental Disorders/pathology , Parvalbumins/metabolism , Receptors, Kainic Acid/metabolism , Receptors, Metabotropic Glutamate/metabolism , Animals , Disease Models, Animal , Female , GABAergic Neurons/metabolism , GABAergic Neurons/pathology , Male , Mice , Mice, Knockout , Receptors, Metabotropic Glutamate/genetics
3.
J Med Eng Technol ; 39(3): 208-15, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25815889

ABSTRACT

Pressure sensors are valuable transducers that are necessary in a huge number of medical application. However, the state of the art of compact and lightweight pressure sensors with the capability of measuring the contact pressure between two surfaces (contact pressure sensors) is very poor. In this work, several types of wearable contact pressure sensors are fabricated using different conductive textile materials and piezo-resistive films. The fabricated sensors differ in size, the textile conductor used and/or the number of layers of the sandwiched piezo-resistive film. The intention is to study, through the obtaining of their calibration curves, their metrological properties (repeatability, sensitivity and range) and determine which physical characteristics improve their ability for measuring contact pressures. It has been found that it is possible to obtain wearable contact pressure sensors through the proposed fabrication process with satisfactory repeatability, range and sensitivity; and that some of these properties can be improved by the physical characteristics of the sensors.


Subject(s)
Monitoring, Ambulatory/instrumentation , Transducers , Calibration , Equipment Design , Pressure , Reproducibility of Results , Textiles
4.
Chemosphere ; 117: 774-80, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25461947

ABSTRACT

Toluene biotrickling filtration under anoxic denitrifying conditions was evaluated in two identical bioreactors (R1 and R2) operated at liquid recycling rates of 1.3, 2.7 and 5.3 m h−1 and liquid renewal rates of 0 and 0.17 d−1. R1 and R2 achieved a similar maximum elimination capacity (EC ∼30 g m−3 h−1) at the same toluene inlet load (∼50 g m−3 h−1), which was approximately 7 times higher compared with available literature on continuous toluene removal under anoxic conditions. Nevertheless, higher metabolite accumulation was observed in the bioreactor operated without periodical liquid phase renewal (R2), leading to intermittent drops in its toluene removal performance. This is the first work operating an anoxic biotrickling filter at empty bed residence time of 3 min, which is comparable with those employed in conventional aerobic systems. A characterization of the metabolites accumulated in the liquid phase revealed a dynamic metabolite production and degradation.


Subject(s)
Environmental Restoration and Remediation/methods , Filtration , Toluene/metabolism , Water Pollutants, Chemical/metabolism , Water Pollution, Chemical/prevention & control , Anaerobiosis , Biodegradation, Environmental , Bioreactors
5.
J Hazard Mater ; 276: 287-94, 2014 Jul 15.
Article in English | MEDLINE | ID: mdl-24887128

ABSTRACT

The performance of a fungal perlite-based biofilter coupled to a post-treatment photoreactor was evaluated over 234 days in terms of n-hexane removal, emission and deactivation of fungal spores. The biofilter and photoreactor were operated at gas residence times of 1.20 and 0.14min, respectively, and a hexane loading rate of 115±5gm(-3)h(-1). Steady n-hexane elimination capacities of 30-40gm(-3)h(-1) were achieved, concomitantly with pollutant mineralization efficiencies of 60-90%. No significant influence of biofilter irrigation frequency or irrigation nitrogen concentration on hexane abatement was recorded. Photolysis did not support an efficient hexane post-treatment likely due to the short EBRT applied in the photoreactor, while overall hexane removal and mineralization enhancements of 25% were recorded when the irradiated photoreactor was packed with ZnO-impregnated perlite. However, a rapid catalyst deactivation was observed, which required a periodic reactivation every 48h. Biofilter irrigation every 3 days supported fungal spore emissions at concentrations ranging from 2.4×10(3) to 9.0×10(4)CFUm(-3). Finally, spore deactivation efficiencies of ≈98% were recorded for the photolytic and photocatalytic post-treatment processes. This study confirmed the potential of photo-assisted post-treatment processes to mitigate the emission of hazardous fungal spores and boost the abatement performance of biotechnologies.


Subject(s)
Filtration/methods , Fungi/metabolism , Hexanes/isolation & purification , Photobioreactors
6.
Clin Exp Immunol ; 177(2): 500-8, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24730624

ABSTRACT

While there is evidence of a pathogenic role for complement in inflammatory bowel disease, there is also evidence for a protective role that relates to host defence and protection from endotoxaemia. There is thus concern regarding the use of systemic complement inhibition as a therapeutic strategy. Local delivery of a complement inhibitor to the colon by oral administration would ameliorate such concerns, but while formulations exist for oral delivery of low molecular weight drugs to the colon, they have not been used successfully for oral delivery of proteins. We describe a novel pellet formulation consisting of cross-linked dextran coated with an acrylic co-polymer that protects the complement inhibitor CR2-Crry from destruction in the gastrointestinal tract. CR2-Crry containing pellets administered by gavage, were characterized using a therapeutic protocol in a mouse model of dextran sulphate sodium (DSS)-induced colitis. Oral treatment of established colitis over a 5-day period significantly reduced mucosal inflammation and injury, with similar therapeutic benefit whether or not the proton pump inhibitor, omeprazole, was co-administered. Reduction in injury was associated with the targeting of CR2-Crry to the mucosal surface and reduced local complement activation. Treatment had no effect on systemic complement activity. This novel method for oral delivery of a targeted protein complement inhibitor will reduce systemic effects, thereby decreasing the risk of opportunistic infection, as well as lowering the required dose and treatment cost and improving patient compliance. Furthermore, the novel delivery system described here may provide similar benefits for administration of other protein-based drugs, such as anti-tumour necrosis factor-α antibodies.


Subject(s)
Colitis/immunology , Colon/drug effects , Colon/immunology , Complement Inactivator Proteins/administration & dosage , Complement System Proteins/immunology , Intestinal Mucosa/drug effects , Intestinal Mucosa/immunology , Administration, Oral , Animals , Colitis/chemically induced , Colitis/drug therapy , Colon/pathology , Complement Activation/drug effects , Complement Activation/immunology , Dextran Sulfate/adverse effects , Disease Models, Animal , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/immunology , Intestinal Mucosa/pathology , Mice , Recombinant Fusion Proteins/administration & dosage
7.
Biomed Mater ; 1(3): 106-15, 2006 Sep.
Article in English | MEDLINE | ID: mdl-18458390

ABSTRACT

The difficulty in performing biomechanical tests and the scarcity of biomechanical experimental databases necessitate extending the current knowledge base to allow efficient modelling using limited data sets. This study suggests a framework to reduce uncertainties in biomechanical systems using limited data sets. The study also shows how sparse data and epistemic input can be exploited using fuzzy logic to represent biomechanical relations. An example application to model collagen fibre recruitment in the medial collateral ligaments during time-dependent deformation under cyclic loading (creep) is presented. The study suggests a quality metric that can be employed to observe and enhance uncertainty tolerance in the modelling process.


Subject(s)
Algorithms , Fuzzy Logic , Ligaments/anatomy & histology , Ligaments/physiology , Models, Biological , Animals , Computer Simulation , Data Interpretation, Statistical , Humans , Reproducibility of Results , Sensitivity and Specificity
9.
Nefrologia ; 25(3): 332-5, 2005.
Article in Spanish | MEDLINE | ID: mdl-16053016

ABSTRACT

Angiodysplasia is an important cause of gastrointestinal bleeding in patients with chronic renal failure. Octreotide, a long-acting synthetic somatostatin analogue that reduces splachnic blood flow have been used to treat esophageal varicose hemorrhage, but its efficacy for bleeding vascular ecstasies is awaiting support. We present three patients with chronic renal failure (two with diabetic nephropaty and the third with mesangiocapilar glomerulonephritis and hepatic cirrosis), seric creatinine 3-4,5 mg/dl, and recurrent gastrointestinal bleeding due to diffuse angiodysplasia and vascular ecstasies, diagnosed by oral endoscopy, colonoscopy and video capsule. They all were treated with octreotide, administered subcutanesly 0.1 mg twice a day for six months, with significantly decreased blood requirements in all of them, as well as the occurrence of bleeding episodes. It was well tolerated and none side-effects occurred in any subject. In our experience, octreotide is an effective and safe drug in bleeding angiodysplasia and ecstasies vascular of the gastrointestinal tract in patients with chronic renal failure, and it may be a good option especially in patients who are not candidates for surgery or endoscopic treatment due to inaccessible sites, spread of the lesion, old age and/or concomitant disorders.


Subject(s)
Angiodysplasia/drug therapy , Kidney Failure, Chronic/drug therapy , Octreotide/therapeutic use , Adult , Aged , Angiodysplasia/etiology , Blood Transfusion , Colonoscopy , Combined Modality Therapy , Diabetes Mellitus, Type 2/complications , Diabetic Nephropathies/complications , Endoscopy , Female , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/therapy , Glomerulonephritis, Membranoproliferative/complications , Humans , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/therapy , Liver Cirrhosis, Alcoholic/complications , Middle Aged , Renal Dialysis
10.
Nefrología (Madr.) ; 25(3): 332-335, mayo 2005. tab
Article in Es | IBECS | ID: ibc-040383

ABSTRACT

La angiodisplasia es una causa frecuente de sangrado digestivo en los pacientes con insuficiencia renal crónica. El octreotide, un análogo sintético de la somatostatina que produce una disminución del flujo esplácnico, utilizado por vía subcutánea y en uso prolongado, se ha propuesto para el tratamiento de las hemorragias digestivas asociadas a angiodisplasia y otras lesiones vasculares en casos seleccionados. Presentamos la historia clínica de tres pacientes con insuficiencia renal crónica avanzada (Cr 3-4,5 mg/dl inicialmente), todos revisados en la consulta de prediálisis y con hemorragias digestivas asociadas a lesiones de angiodisplasia y en un caso ectasias vasculares asociadas a cirrosis hepática, diagnosticadas por endoscopia oral, colonoscopia, y videocápsula en un caso. Todos recibieron octreotide por vía subcutánea a dosis de 0,1 mg/12 h, por un periodo inicial de 6 meses, con disminución llamativa de las necesidades transfusionales en dos casos y desaparición de las mismas en uno. La medicación fue bien tolerada, no refiriendo ningún efecto secundario. En nuestra experiencia, el octreotide ha resultado eficaz para disminuir las necesidades transfusionales en pacientes con insuficiencia renal crónica y hemorragias por lesiones vasculares (angiodisplasia y ectasia vascular asociada a cirrosis hepática), y puede ser un complemento o una alternativa al tratamiento quirúrgico y/o endoscópico en los casos recidivantes, en los en los que las lesiones no están accesibles o en los que la comorbilidad del paciente lo hace poco aconsejable


Angiodysplasia is an important cause of gastrointestinal bleeding in patients with chronic renal failure. Octreotide, a long-acting synthetic somatostatin analogue that asoreduces splachnic blood flow have been used to treat esophageal varicose hemorrhage, but its efficacy for bleeding vascular ecstasies is awaiting support. We present three patients with chronic renal failure (two with diabetic nephropaty and the third with mesangiocapilar glomerulonephritis and hepatic cirrosis), seric creatinine 3-4,5 mg/dl, and recurrent gastrointestinal bleeding due to diffuse angiodysplasia and vascular ecstasies, diagnosed by oral endoscopy, colonoscopy and video capsule. They all were treated with octreotide, administered subcutanesly 0.1 mg twice a day for six months, with significantly decreased blood requirements in all of them, as well as the occurrence of bleeding episodes. It was well tolerated and none side-effects occurred in any subject. In our experience, octreotide is an effective and safe drug in bleeding angiodysplasia and ecstasies vascular of the gastrointestinal tract in patients with chronic renal failure, and it may be a good option especially in patients who are not candidates for surgery or endoscopic treatment due to inaccessible sites, spread of the lesion, old age and/or concomitant disorders


Subject(s)
Aged , Humans , Gastrointestinal Hemorrhage/diagnosis , Gastrointestinal Hemorrhage/prevention & control , Angiodysplasia , Renal Insufficiency, Chronic/complications , Injections, Subcutaneous , Liver Cirrhosis/complications , Endoscopy, Digestive System , Colonoscopy
11.
Rev. argent. radiol ; 69(2): 127-130, abr.2005. ilus
Article in Spanish | LILACS | ID: lil-421689

ABSTRACT

Propósito: Nos llamó la atención la frecuencia de luxaciones rotulianas traumáticas (LRT) no sospechadas durante la consulta y el examen físico de pacientes que exploramos por gonalgia o inestabilidad mediante resonancia magnética (RM). Nuestro Objetivo es demostrar los signos de LRT que hallamos en estos pacientes y las estructuras anatómicas que resultan más frecuentemente afectadas. Material y método: Diez y ocho pacientes con LRT fueron explorados mediante RM con cortes axiales, coronales y sagitales ponderados en T1 y T2. Resultados: El 61,1 por ciento de los pacientes no presentaba sospecha de LRT antes del examen y relataba un episodio de esguince o traumatismo como comienzo de los síntomas; el 83,3 por ciento mostró lesión del retináculo interno y el ligamento femoropatelar (LFP). Las contusiones óseas en la cara medial de la rótula estuvieron presentes en el 88,8 por ciento y en el borde lateral del cóndilo femoral externo en el 100 por ciento. El 1,1 por ciento mostró un fragmento óseo patelar desprendido y el 55,5 por ciento mostró lateral del cóndilo femoral externo en el 100 por ciento. El 1,1 por ciento mostró un fragmento óseo patelar desprendido y el 55,5 por ciento mostró lateral del cóndilo femoral externo en el 100 por ciento. El 1,1 por ciento mostró un fragmento óseo patelar desprendido y el 55,5 por ciento mostró condromalacia traumática. Todos presentaron derrame articular. "Patela alta" se comprobó en el 55,5 por ciento de los casos. La rótula subluxada estuvo presente en el 72,2 por ciento. Conclusión: La LRT pasa muchas veces desapercibida en la consulta traumatológica. La RM constituye en un método eficáz para su diagnóstico, siempre y cuando se interpreten correctamente los signos de presentación de esta patología. El diagnóstico correcto de una lesión no sospechada puede provocar un cambio en la terapéutica y el manejo del paciente


Subject(s)
Adult , Male , Humans , Female , Child , Adolescent , Middle Aged , Joint Dislocations , Knee Injuries , Patella/injuries , Knee Injuries , Magnetic Resonance Imaging
12.
Rev. argent. radiol ; 69(2): 127-130, abr.2005. ilus
Article in Spanish | BINACIS | ID: bin-822

ABSTRACT

Propósito: Nos llamó la atención la frecuencia de luxaciones rotulianas traumáticas (LRT) no sospechadas durante la consulta y el examen físico de pacientes que exploramos por gonalgia o inestabilidad mediante resonancia magnética (RM). Nuestro Objetivo es demostrar los signos de LRT que hallamos en estos pacientes y las estructuras anatómicas que resultan más frecuentemente afectadas. Material y método: Diez y ocho pacientes con LRT fueron explorados mediante RM con cortes axiales, coronales y sagitales ponderados en T1 y T2. Resultados: El 61,1 por ciento de los pacientes no presentaba sospecha de LRT antes del examen y relataba un episodio de esguince o traumatismo como comienzo de los síntomas; el 83,3 por ciento mostró lesión del retináculo interno y el ligamento femoropatelar (LFP). Las contusiones óseas en la cara medial de la rótula estuvieron presentes en el 88,8 por ciento y en el borde lateral del cóndilo femoral externo en el 100 por ciento. El 1,1 por ciento mostró un fragmento óseo patelar desprendido y el 55,5 por ciento mostró lateral del cóndilo femoral externo en el 100 por ciento. El 1,1 por ciento mostró un fragmento óseo patelar desprendido y el 55,5 por ciento mostró lateral del cóndilo femoral externo en el 100 por ciento. El 1,1 por ciento mostró un fragmento óseo patelar desprendido y el 55,5 por ciento mostró condromalacia traumática. Todos presentaron derrame articular. "Patela alta" se comprobó en el 55,5 por ciento de los casos. La rótula subluxada estuvo presente en el 72,2 por ciento. Conclusión: La LRT pasa muchas veces desapercibida en la consulta traumatológica. La RM constituye en un método eficáz para su diagnóstico, siempre y cuando se interpreten correctamente los signos de presentación de esta patología. El diagnóstico correcto de una lesión no sospechada puede provocar un cambio en la terapéutica y el manejo del paciente (AU)


Subject(s)
Adult , Male , Humans , Female , Child , Adolescent , Middle Aged , Patella/injuries , Knee Injuries/diagnosis , Joint Dislocations/diagnosis , Knee Injuries/complications , Magnetic Resonance Imaging
15.
Environ Monit Assess ; 72(2): 179-206, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11720223

ABSTRACT

The Republican River Basin of Colorado, Nebraska, and Kansas lies in a valley which contains Pierre Shale as part of its geological substrata. Selenium is an indigenous constituent in the shale and is readily leached into surrounding groundwater. The Basin is heavily irrigated through the pumping of groundwater, some of which is selenium-contaminated, onto fields in agricultural production. Water, sediment, benthic invertebrates, and/or fish were collected from 46 sites in the Basin and were analyzed for selenium to determine the potential for food-chain bioaccumulation, dietary toxicity, and reproductive effects of selenium in biota. Resulting selenium concentrations were compared to published guidelines or biological effects thresholds. Water from 38% of the sites (n = 18) contained selenium concentrations exceeding 5 microg L(-1), which is reported to be a high hazard for selenium accumulation into the planktonic food chain. An additional 12 sites (26% of the sites) contained selenium in water between 3-5 microg L(-1), constituting a moderate hazard. Selenium concentrations in sediment indicated little to no hazard for selenium accumulation from sediments into the benthic food chain. Ninety-five percent of benthic invertebrates collected exhibited selenium concentrations exceeding 3 microg g(-1), a level reported as potentially lethal to fish and birds that consume them. Seventy-five percent of fish collected in 1997, 90% in 1998, and 64% in 1999 exceeded 4 microg g(-1) selenium, indicating a high potential for toxicity and reproductive effects. However, examination of weight profiles of various species of collected individual fish suggested successful recruitment in spite of selenium concentrations that exceeded published biological effects thresholds for health and reproductive success. This finding suggested that universal application of published guidelines for selenium may be inappropriate or at least may need refinement for systems similar to the Republican River Basin. Additional research is needed to determine the true impact of selenium on fish and wildlife resources in the Basin.


Subject(s)
Environmental Exposure , Fishes/metabolism , Invertebrates/metabolism , Selenium/analysis , Water Pollutants, Chemical/analysis , Animals , Colorado , Fishes/physiology , Fresh Water/analysis , Geologic Sediments/analysis , Kansas , Nebraska , Reproduction/drug effects , Selenium/pharmacokinetics , Selenium/toxicity , Water Pollutants, Chemical/pharmacokinetics , Water Pollutants, Chemical/toxicity
16.
Rev Alerg Mex ; 48(4): 103-6, 2001.
Article in Spanish | MEDLINE | ID: mdl-11593912

ABSTRACT

OBJECTIVE: To study the magnitude of risk factors known for asthma in 6-10 year-old children. MATERIAL AND METHODS: This is a case- and control-study with 6-10 year-old children; 58 were asthmatic and 117 were control, with a relation 2:1. Asthmatic patients were recruited from consult of immuno-allergies department and control patients, from familial medicine consult of Hospital de Especialidades 71, IMSS. Indirect (mother) and directed surveys were applied, they were of multiple option for exploring the most known in literature-risk factors. Statistical management was performed by odds ratio with confidence interval of 95%. RESULTS: The following variables were considered risk factors: ingestion of artificial colorants before having 1 year old (OR = 13.2), living in an urban area (OR = 7.74), maternal smoking during pregnancy (OR = 2.4), wool contact before having 1 year old (OR = 2.11), passive smoking exposure during pregnancy (OR = 1.486) and feeding with industrialized milk (OR = 1.2). CONCLUSIONS: Environmental risk factors are very important in our population, as well as early ablactation; however, ingestion before having 1 year old of allergens as egg, chocolate, orange and mango was not considered risk factor.


Subject(s)
Asthma/etiology , Asthma/epidemiology , Case-Control Studies , Child , Female , Humans , Male , Risk Factors , Spain
17.
Fertil Steril ; 76(4): 723-9, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11591405

ABSTRACT

OBJECTIVE: To examine the effects of alcohol, caffeine, and tobacco use on early follicular phase FSH, LH, E2, and sex hormone-binding globulin (SHBG). DESIGN: Cross-sectional study. SETTING: Academic medical center. PATIENT(S): Four hundred ninety-eight women selected from the general population, ages 36-45, who were not currently pregnant, breast feeding, or using exogenous hormones. INTERVENTION(S): A general questionnaire assessing demography, anthropometry, and smoking habits and a standardized dietary questionnaire assessing food and beverage frequencies, including sources of alcohol and caffeine. MAIN OUTCOME MEASURE(S): FSH, LH, E2, and SHBG levels measured during the early follicular phase of the menstrual cycle. RESULT(S): Significant associations observed in a univariate analysis included age > or =40 and current smoking associated with higher FSH; higher body mass index (BMI) associated with lower SHBG levels; and daily alcohol use, cholesterol consumption greater than the median, and coffee use >1 cup/d associated with higher E2 levels. In a multivariate model, total caffeine use was significantly associated with E2 levels after adjustment for age, BMI, total calories, current smoking, alcohol, cholesterol consumption, and day of sampling. Early follicular phase E2 increased from 28.2 pg/mL for women consuming < or =100 mg of caffeine to 45.2 pg/mL for women consuming > or =500 mg of caffeine per day, about a 70% increase. CONCLUSION(S): Coffee consumption and total caffeine use may increase early follicular phase E2 levels independent of related habits of alcohol or tobacco use.


Subject(s)
Alcohol Drinking , Coffee , Drinking , Follicular Phase/metabolism , Hormones/blood , Smoking , Adult , Caffeine/pharmacology , Cross-Sectional Studies , Dose-Response Relationship, Drug , Estradiol/blood , Female , Humans , Middle Aged
18.
J Cereb Blood Flow Metab ; 21(7): 835-46, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11435796

ABSTRACT

The integrity of cerebral microvessels requires the close apposition of the endothelium to the astrocyte endfeet. Integrins alpha1beta1 and alpha6beta4 are cellular matrix receptors that may contribute to cerebral microvascular integrity. It has been hypothesized that focal ischemia alters integrin expression in a characteristic time-dependent manner consistent with neuron injury. The effects of middle cerebral artery occlusion (MCAO) and various periods of reperfusion on microvasclar integrin alpha1beta1 and alpha6beta4 expression were examined in the basal ganglia of 17 primates. Integrin subunits alpha1 and beta1 colocalized with the endothelial cell antigen CD31 in nonischemic microvessels and with glial fibrillary acidic protein on astrocyte fibers. Rapid, simultaneous, and significant disappearance of both integrin alpha1 and beta1 subunits and integrin alpha6beta4 occurred by 2 hours MCAO, which was greatest in the region of neuron injury (ischemic core, Ic), and progressively less in the peripheral (Ip) and nonischemic regions (N). Transcription of subunit beta1 mRNA on microvessels increased significantly in the Ic/Ip border and in multiple circular subregions within Ic. Microvascular integrin alpha1beta1 and integrin alpha6beta4 expression are rapidly and coordinately lost in Ic after MCAO. With loss of integrin alpha1beta1, multiple regions of microvascular beta1 mRNA up-regulation within Ic suggest that microvessel responses to focal ischemia are dynamic, and that multiple cores, not a single core, are generated. These changes imply that microvascular integrity is modified in a heterogeneous, but ordered pattern.


Subject(s)
Antigens, Surface/genetics , Gene Expression , Integrins/genetics , Ischemic Attack, Transient/metabolism , Animals , Antigens, Surface/analysis , Astrocytes/chemistry , Glial Fibrillary Acidic Protein/analysis , Immunohistochemistry , In Situ Hybridization , Integrin alpha1beta1 , Integrin alpha6beta4 , Integrins/analysis , Ischemic Attack, Transient/pathology , Male , Microcirculation/chemistry , Microscopy, Confocal , Middle Cerebral Artery , Neurons/pathology , Papio , Platelet Endothelial Cell Adhesion Molecule-1/analysis , RNA, Messenger/analysis
19.
Stroke ; 32(6): 1341-8, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11387497

ABSTRACT

BACKGROUND AND PURPOSE: During focal cerebral ischemia, the microvascular matrix (ECM), which participates in microvascular integrity, is degraded and lost when neurons are injured. Loss of microvascular basal lamina antigens coincides with rapid expression of select matrix metalloproteinases (MMPs). Plasminogen activators (PAs) may also play a role in ECM degradation by the generation of plasmin or by MMP activation. METHODS: The endogenous expressions of tissue-type plasminogen activator (tPA), urokinase (uPA), and PA inhibitor-1 (PAI-1) were quantified in 10-microm frozen sections from ischemic and matched nonischemic basal ganglia and in the plasma of 34 male healthy nonhuman primates before and after middle cerebral artery occlusion (MCA:O). RESULTS: Within the ischemic basal ganglia, tissue uPA activity and antigen increased significantly within 1 hour after MCA:O (2P<0.005). tPA activity transiently decreased 2 hours after MCA:O (2P=0.01) in concert with an increase in PAI-1 antigen (2P=0.001) but otherwise did not change. The transient decrease in free tPA antigen was marked by an increase in the tPA-PAI-1 complex (2P<0.001). No significant relations to neuronal injury or intracerebral hemorrhage were discerned. CONCLUSIONS: The rapid increase in endogenous PA activity is mainly due to significant increases in uPA, but not tPA, within the ischemic basal ganglia after MCA:O. This increase and an increase in PAI-1 coincided with latent MMP-2 generation and microvascular ECM degeneration but not neuronal injury.


Subject(s)
Infarction, Middle Cerebral Artery/metabolism , Plasminogen Activators/biosynthesis , Acute Disease , Animals , Basal Ganglia/blood supply , Basal Ganglia/metabolism , Basal Ganglia/pathology , Brain Ischemia/metabolism , Brain Ischemia/pathology , Cell Count , Cerebral Hemorrhage/etiology , Cerebral Hemorrhage/pathology , Disease Models, Animal , Enzyme Activation , Gelatin/metabolism , Immunoblotting , Infarction, Middle Cerebral Artery/complications , Infarction, Middle Cerebral Artery/pathology , Male , Microcirculation/pathology , Neurons/pathology , Papio , Plasminogen Activator Inhibitor 1/biosynthesis , Plasminogen Activator Inhibitor 1/blood , Plasminogen Activators/blood , Tissue Plasminogen Activator/biosynthesis , Tissue Plasminogen Activator/blood , Urokinase-Type Plasminogen Activator/biosynthesis , Urokinase-Type Plasminogen Activator/blood
20.
J Acoust Soc Am ; 108(4): 1408-20, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11051467

ABSTRACT

The harmonics-to-noise ratio (HNR) has been used to quantify the waveform irregularity of voice signals [Yumoto et al., J. Acoust. Soc. Am. 71, 1544-1550 (1982)]. This measure assumes that the signal consists of two components: a harmonic component, which is the common pattern that repeats from cycle-to-cycle, and an additive noise component, which produces the cycle-to-cycle irregularity. It has been shown [J. Qi, J. Acoust. Soc. Am. 92, 2569-2576 (1992)] that a valid computation of the HNR requires a nonlinear time normalization of the cycle wavelets to remove phase differences between them. This paper shows the application of functional data analysis to perform an optimal nonlinear normalization and compute the HNR of voice signals. Results obtained for the same signals using zero-padding, linear normalization, and dynamic programming algorithms are presented for comparison. Functional data analysis offers certain advantages over other approaches: it preserves meaningful features of signal shape, produces differentiable results, and allows flexibility in selecting the optimization criteria for the wavelet alignment. An extension of the technique for the time normalization of simultaneous voice signals (such as acoustic, EGG, and airflow signals) is also shown. The general purpose of this article is to illustrate the potential of functional data analysis as a powerful analytical tool for studying aspects of the voice production process.


Subject(s)
Sound Spectrography/statistics & numerical data , Voice , Data Interpretation, Statistical , Humans , Reference Values
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