HERNANDO A. CHAVEZ

Casio (Japan)

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R Ibarra

Hospital Vozandes

A Arancibia

Amgen (United States)

RODOLFO IBARRA

The University of Texas Health Science Center at Houston

Leonardo Tovar González

Universidad Michoacana de San Nicolás de Hidalgo

J. Chávez

Universidad de Guadalajara

Denise Marques Garcia

Universidad Michoacana de San Nicolás de Hidalgo

AND J. RANDY JINKINS

SUNY Downstate Health Sciences University

J Chávez

Central University of Ecuador

S Thambo

University of Chile

F. CRUZ

Universidad Michoacana de San Nicolás de Hidalgo

Cooperative Institutions

Universidad Michoacana de San Nicolás de Hidalgo

Nesta

Universidad de Congreso

Casio (Japan)

University of Chile

The University of Texas Health Science Center at Houston

The University of Texas Health Science Center at San Antonio

Hospital Vozandes

Amgen (United States)

Universidad de Santiago de Chile

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Disposition kinetics of dibekacin in normal subjects and in patients with renal failure.

PubMed (1987)

A Arancibia J Chávez R Ibarra Irene Ruíz A Icarte

Dibekacin pharmacokinetics was studied in ten healthy volunteers and six patients with renal failure presenting Clcr less than 10 ml X min-1 per 1.73 m2 of body surface, given as a slow intravenous bolus to the volunteers and as a 30-minute intravenous infusion to the patients. The antibiotic was assayed in plasma and urine by means of a microbiological method using Bacillus subtilis. A two-compartment kinetic model was used to describe the bi-phasic decline of the plasma concentration thus establishing the different pharmacokinetic parameters. Elimination parameters beta, k10 and total body clearance were markedly diminished in renal patients (p less than 0.001): t1/2 beta was 2.0 h, k10 = 0.016 min-1 and Cl = 0.87 ml X min-1 kg body weight in normal subjects and t1/2 beta = 21.4 h, k10 = 0.0011 min-1 and Cl = 0.131 ml X min-1 per kg in the patients. Other kinetic parameters, as distribution (alpha) and transfer (k12, k21) constants were lower in patients than in volunteers. Also the different terms of volume of distribution of the two-compartment model (V1, Vdss, Vdarea) were significantly higher in patients than in normal subjects (p less than 0.05). A good correlation (r = 0.987) between patients' beta constant and creatinine clearance was found. A similar relationship between serum creatinine levels and disposition half-life was found (r = 0.955). Urinary recovery at 24 h was 89.0% of the dose given to normals and 15.8% of the dose given to patients.

Intravenous bolus

Elimination rate constant

Bolus (digestion)

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Acute and Subacute Physiological and Histological Studies of the Central Nervous System After Intrathecal Gadolinium Injection in the Anesthetized Rat

Investigative Radiology (2001)

Glenn M. Toney HERNANDO A. CHAVEZ RODOLFO IBARRA AND J. RANDY JINKINS

Toney GM, Chavez HA, Ibarra R, et al. Acute and subacute physiological and histological studies of the central nervous system after intrathecal gadolinium injection in the anesthetized rat. Invest Radiol 2001:36:33–40. RATIONALE AND OBJECTIVES. To determine the acute physiological and subacute neurohistological effects of gadopentetate dimeglumine (GdD) administered intrathecally. METHODS. Twenty-four rats were separated into two study groups. In the first group, the acute effects of intrathecal GdD on cortical electroencephalographic activity, renal sympathetic nerve activity, arterial blood pressure, and heart rate were determined. In the second group, histological evaluation of the neural tissues was performed 10 days after treatment. In both the physiological and histological studies, a single GdD dose of 2.5 μmol/g brain (10 μL) was administered intrathecally. Control animals were injected intrathecally with the same volume of a sucrose solution that had the same osmolality as GdD. RESULTS. In the physiological study, GdD and sucrose injections elicited no significant change in any of the parameters recorded. In the histologic study, examination revealed two cases of pre-existing chronic spinal cord gliosis; one of these rats also exhibited signs of pre-existing chronic choroid plexus inflammation. No acute or subacute alterations observed could be specifically linked to the intrathecal administration of GdD. CONCLUSIONS. Intrathecally administered GdD was accompanied by no significant change in any of the physiologic or histologic parameters examined. Based on the relatively short time interval between GdD treatment and histologic examination, the neural tissue abnormalities (gliosis/inflammation) observed in two animals were judged to be incidental and likely due to prior chronic pre-existing processes such as viral infection. Although additional studies are required to verify the safety and effectiveness of intrathecal GdD in humans, data from the present study in animals provide evidence that when intrathecal GdD is used in doses sufficient to improve MRI of the cerebrospinal fluid compartment, it is likely to be accompanied by a low incidence of acute changes in neural function or structure.

Gliosis

10.1097/00004424-200101000-00005

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EVALUACIÓN DE LOS CRITERIOS DE DURABILIDAD EN MEZCLAS DE MORTERO CON MUCILAGO DE MARALFALFA

MEMORIAS CONPAT 2019 (2019)

Leonardo Tovar González HERNANDO A. CHAVEZ F. CRUZ J. Chávez Denise Marques Garcia

En esta investigación se determinan los criterios de durabilidad con respecto de pruebas no destructivas en las que se hizo una experimentación con un material totalmente innovador como lo es la maralfalfa, este material es de muy fácil producción y aprovechamiento.Se empleó en mezclas de mortero produciendo especímenes para determinar sus características mecánicas realizando pruebas de naturaleza no destructiva tales como: resistividad eléctrica y velocidad de pulso ultrasónico comparando los resultados con los criterios de la red DURAR.Se observa un retraso

10.21041/conpat2019/v1cc120

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Citations (2)