Search PubMed⌕ Search

Biomedical subjects

P Pastor

Publications and source records attributed to P Pastor.

At least 37 records · Page 2Linked to original sources
PubMed1999

[New pharmacologic strategies for the treatment of Parkinson disease].

The dopamine precursor, levodopa, and the synthetic dopamine agonists are drugs widely used to alleviate the motor symptoms of idiopathic Parkinson's disease. Recently, several molecules which act on different pharmacological receptors implied in Parkinson's disease pathophysiology, have been developed to be applied as a treatment for its motor and cognitive symptoms. This paper discusses these novel therapeutical strategies, their mechanism of action, and their potential applications. To facilitate its lecture, the article has been structured in several sections. In the first section, drugs acting on dopamine metabolism are described, in the next part recent studies on new dopamine agonists and drugs acting on non-dopamine neuronal receptors are analysed, and finally the role of trophic factors for the treatment of Parkinson's disease is discussed.

Antiparkinson Agents↗
PubMed1998

Recruitment curve of the soleus H reflex in patients with neurogenic claudication.

The diagnosis of neurogenic claudication (NC) remains uncertain when no definite signs of radicular lesions are found in electrophysiological testing. However, the functional deficit could be demonstrated during the brief time in which the patients complain of pain and weakness in the muscles of the lower limbs after walking. We have used electrophysiological testing of the H reflex and the F wave to document the transient functional derangement expected to occur at the radicular level in patients with NC after walking. We examined the recruitment curve of the soleus H reflex, and the chronodispersion of the posterior tibial nerve F wave, at rest and after a walking exercise that triggered their symptoms in 10 patients with NC, with no positive electrophysiological findings of radicular lesion. The same studies were performed in 5 age-matched healthy volunteers, used as control subjects, who were asked to walk for 30 min. At rest before walking, no abnormalities were found in any of the patients. After walking, the H wave showed a transient increase in its threshold with respect to that of the M wave in 7 patients (70%). Such abnormality lasted for a mean period of 7 min. In 2 of these patients there was also an increase in the F-wave chronodispersion. Our data suggest that nerve conduction is transiently blocked in large myelinated fibers at a radicular level in patients with NC after walking. Partial interruption of the H-reflex circuit could be one of the pathophysiological mechanisms underlying NC.

Adult↗
PubMed1998

Invasive pneumococcal disease in Dallas County, Texas: results from population-based surveillance in 1995.

We studied the epidemiology of invasive disease caused by Streptococcus pneumoniae in 1995 among 1.9 million residents of Dallas County, Texas. The sociodemographic characteristics and chronic medical conditions of 432 patients were identified through active, population-based surveillance and review of medical records. The incidence of disease was 22 cases per 100,000 person-years and was highest for children < 2 years of age (136 cases per 100,000 person-years) and for adults > or = 65 years of age (80 cases per 100,000 person-years). Twenty percent of isolates were nonsusceptible to penicillin; the highest rates of resistance were among the youngest and oldest age groups (28% and 22% of isolates, respectively). An increased incidence of disease was associated with low income (42 cases per 100,000 person-years) and black race (39 cases per 100,000 person-years). The frequency of most chronic medical conditions increased with age; smoking, heavy alcohol use, and infection due to human immunodeficiency virus were most common between 30 and 64 years of age. Of otherwise healthy patients 30-64 years of age, 47% were current smokers, an association requiring further investigation. Characterizing groups at risk for invasive pneumococcal disease could aid in the development of prevention programs and increase the benefits from wide use of effective vaccines.

Adolescent↗
PubMed1998

Methicillin-resistant Staphylococcus aureus in two child care centers.

Methicillin-resistant Staphylococcus aureus (MRSA) has not been studied in child care centers. The prevalence of MRSA colonization was determined at two centers with an index patient. Two (3%) of 61 children at center X had MRSA; strains from both children and the index illness were pulsed-field gel electrophoresis type B. Nine (24%) of 40 children at center Y had MRSA; strains from 5 children and the index illness were type B, and strains from 4 children were type A. Ten of 11 colonized children were in classes with 2- and 3-year-old children. Colonization with MRSA was not associated with health care contact by subjects or by members of their households. MRSA in child day care centers indicates accelerated spread of MRSA in the community.

Child↗
PubMed1997

Identification of Spanish familial Parkinson's disease and screening for the Ala53Thr mutation of the alpha-synuclein gene in early onset patients.

We initiated the present work in order to determine if the Ala53Thr mutation of the alpha-synuclein gene previously described by Polymeropoulos et al. [Science, 276 (1997) 2045-2047] could be detected in Spanish early onset Parkinson's disease (PD) patients. Thirty-four PD patients were evaluated. Of these, 13 were considered early onset patients (six familial and seven sporadic) and were included in the genetic study. We detected the presence of genetic anticipation in four kindreds with early onset PD members. The Ala53Thr mutation of the alpha-synuclein gene was absent in all patients. The results do not support a role for this mutation in our patients with early onset PD and, in agreement with the results previously reported, indicate that the Ala53Thr mutation of the alpha-synuclein gene is a rare cause of PD.

Adult↗
PubMed1997

Pleural and peritoneal leishmaniasis in an AIDS patient.

The case of an AIDS patient who developed pleuritis and peritonitis in the course of relapsing visceral leishmaniasis is reported. Visceral leishmaniasis, considered an opportunistic infection in patients infected with the human immunodeficiency virus (HIV) who live in endemic areas, has a chronic relapsing course. Typical manifestations such as fever, hepatosplenomegaly, lymphadenopathy, weight loss, or pancytopenia are not specific in advanced HIV infection. Atypical clinical presentations are becoming more frequent. This is believed to be the first report of peritoneal involvement by Leishmania in an AIDS patient.

AIDS-Related Opportunistic Infections↗
PubMed1997

Factors associated with unnecessary immunization given to children.

OBJECTIVE: To determine the factors associated with unnecessary immunization during the pre-school years. METHODS: Children were selected from birth certificates and their parents were interviewed to identify all immunizations to 72 months of age. The immunizations were verified. RESULTS: Of 187 children studied 34 (18%) received unnecessary immunization. Unnecessary immunization was strongly associated with ever receiving immunization in a large system of public clinics (designated "Public A") (33%) compared with other providers (5%) (P < 0.00001). Among children immunized in Public A, unnecessary immunization was associated with the parent having an incomplete or no copy of the child's immunization record (P = 0.007) and with not being up to date for immunizations at 24 months of age (P = 0.04). Complete documentation of immunizations either in the Public. A record or in the parent's copy of the record was associated with a 4% rate of unnecessary immunization; incomplete or no documentation in both the Public A and the parent's record was associated with a 45% rate of unnecessary immunization (P = 0.001). CONCLUSIONS: Access to a complete immunization record, be it the provider's, the parent's or ideally both, decreases substantially a child's risk of unnecessary immunization.

Analysis of Variance↗
PubMed1995

Pediatric clinical clerkships are associated with an excess risk of acute infection.

OBJECTIVE: To determine the incidence of acute respiratory and gastrointestinal tract illness and associated absence by third-year medical students during pediatric and nonpediatric (control) clinical clerkships. DESIGN: A self-administered questionnaire was completed by students after the first 4 weeks of two pediatric clerkships (inpatient and outpatient) and two non-pediatric clerkships (obstetrics-gynecology and psychiatry). Information was obtained on the symptoms of acute respiratory and gastrointestinal tract illness and related absences. ANALYSIS: Results from each student's pediatric clerkship were compared with the results from the same student's control clerkship by means of matched-pair analysis. SUBJECTS: Students who made up the junior class at the University of Texas Southwestern Medical School at Dallas, July 1, 1990, to June 30, 1991. RESULTS: Of 177 students (77%) who completed questionnaires after one pediatric and one control clerkship, 108 students (61%) had had an acute illness while on pediatric clerkships in contrast to 69 students (39%) on control clerkships (odds ratio, 3.3; 95% confidence interval, 2.0 to 5.4; P < .001). More students were absent for illness during pediatric than control clerkships (23 [13%] vs nine [5%], respectively; odds ratio, 2.7; 95% confidence interval, 1.2 to 6.2; P = .02). The higher risk of illness during pediatric clerkships was not related to the order of the pediatric or control clerkship, the order of inpatient and outpatient pediatrics, or the season of the year. CONCLUSION: Pediatric clinical clerkships in the third year of medical school were associated with excess morbidity from acute infectious illness. Studies are needed to determine whether emphasizing infection control practices decrease this morbidity and any resulting nosocomial spread to patients.

Absenteeism↗
PubMed1995

Estimating immunization coverage from school-based childhood immunization records.

To determine the accuracy of school-based childhood immunization records and to describe the effects of their use on estimates of community-wide immunization coverage, we verified the immunizations to 72 months of age for children born in 1986 to residents in Dallas County, TX, and in Minnesota. Verified immunizations were compared with those documented in the school record. Major transcription errors accounted for fewer than 1% of discrepancies between school and provider records. For 99 subjects with 987 verified immunizations in Minnesota, age-appropriate immunization coverage estimated from the school records was within two percent of actual coverage. For 86 subjects with 981 verified immunizations in Dallas County, age-appropriate immunization coverage from the school records underestimated actual coverage by as much as 21%. The primary factor explaining the underestimate in Dallas was incomplete school immunization records for 33 (38%) subjects and 126 (13%) immunizations. Selective recording of immunizations related to the minimum state requirements in Texas contributed to incomplete school records in Dallas County. Verification of the completeness of records selected to estimate immunization coverage is essential if the estimates are used to monitor trends or to make public policy decisions.

Child↗
PubMed1995

[Cerebral vascular complications in Conn's disease: report of two cases].

We report two patients with arterial hypertension (AHT) secondary to Conn's disease and cerebral vascular accident (CVA). Both had histories of long-standing AHT that had been poorly controlled with drugs, though no complications had developed up to the time of presentation. One CVA was a hemorrhage in the right capsular-lenticular region and the other was a cerebral ischemic infarction. Blood tests done upon admission found low potassium levels. The final clinical-pathological diagnosis was primary hyperaldosteronism secondary to suprarenal adenoma. After laparoscopic surgery AHT reverted to normal in one patient. Although Conn's disease is a rare cause of AHT, early diagnosis and treatment can provide a cure and prevent the development of severe complications.

Adenoma↗
PubMed1994

[Evaluation of prostatic specific antigen after a digital rectal examination: experience with 36 patients].

Levels of prostatic specific antigen may be modified with procedures over the prostatic gland. We measured this antigen in 36 hospitalized patients before and immediately after a digital rectal examination. Antigen levels were 8.3 +/- 21.3 ng/ml before and 13.8 +/- 27.5 ng/ml after the examination (NS). It is concluded that digital rectal examination did not modify antigen levels in our sample.

Adult↗
PubMed1993

Declining incidence of Haemophilus influenzae type b disease since introduction of vaccination.

OBJECTIVE: To determine the incidence of invasive Haemophilus influenzae type b disease in children living in Minnesota and Dallas County, Texas, before and since introduction of plain polysaccharide vaccine in 1985, and conjugate vaccine in 1988. Initially, use of these vaccines was limited to infants 18 months of age and older. DESIGN: Identification of culture-proven cases of H influenzae type b disease was through systems of active, laboratory-based surveillance. The mean incidence of disease (cases observed/100,000 child-years) for 1983 and 1984 served as a baseline for comparison with subsequent years through 1991. PARTICIPANTS: Children less than 5 years of age in Minnesota and Dallas County, Texas. Overall, there were 2557 confirmed age-eligible cases of invasive H influenzae type b disease from 1983 through 1991. RESULTS: Between the 1983-1984 baseline and 1991, the incidence of H influenzae type b disease decreased 85% in Minnesota and 92% in Dallas. Notably, declines in incidence were observed in children in the age group being vaccinated as well as in infants younger than 18 months of age prior to introduction of vaccination. CONCLUSION: In two widely separated areas of the United States, a profound decrease in the incidence of H influenzae type b disease has occurred. The data suggest that vaccination may be protecting against disease, as well as decreasing the spread of infection to unvaccinated infants.

Bacterial Capsules↗
PubMed1993

Ethnicity and socioeconomic status: impact on the diagnosis of congenital heart disease.

OBJECTIVES: The purpose of this study was to estimate the prevalence rates of specific cardiac defects for three ethnic groups and to determine the effects of ethnicity, family income and household education level on the timing of referral for pediatric cardiac care. BACKGROUND: Previous studies examining ethnic differences in rates of congenital heart disease were based on hospital referrals or were limited to diagnoses made in the 1st year of life. These limitations may lead to potential biases in the ascertainment of cases. The present study is population based and includes patients diagnosed after the 1st year of life. METHODS: Cases of congenital heart disease were enumerated among 379,561 liveborn infants to black, white and Mexican-American residents in Dallas County, Texas. Diagnosis was made on the basis of examination by a pediatric cardiologist, two-dimensional echocardiographic studies, cardiac catheterization or observations at operation or at autopsy. Ethnicity, median family income and household educational level were determined from birth certificate information. RESULTS: White children had higher prevalence rates for aortic stenosis, endocardial cushion defect and ventricular septal defect. Mexican-American children had the lowest rate for hypoplastic left heart syndrome. The median age at referral to a pediatric cardiologist was 1.9 months for blacks, 2.1 months for whites and 2.2 months for Mexican-Americans. Stratifying the cases by median family income and household educational level failed to show any significant relation to age at referral. CONCLUSIONS: Prevalence rates of specific cardiac defects vary among black, white and Mexican-American children, probably reflecting different genetic and environmental backgrounds. The timing of referral for pediatric cardiac care, however, was not related to ethnicity, median family income or household educational level.

Black or African American↗
PubMed1993

Decreased Haemophilus colonization in children vaccinated with Haemophilus influenzae type b conjugate vaccine.

OBJECTIVE: The incidence of invasive Haemophilus disease has unexpectedly decreased in unvaccinated children since the introduction of conjugate vaccine in the United States. The purpose of this study was to determine whether conjugate vaccination decreases colonization with Haemophilus influenzae type b. DESIGN: This study was a prospective, bimonthly survey of pharyngeal colonization with H. influenzae type b in children attending day care from October 1987 through September 1989. Vaccination status was determined from the medical record. SUBJECTS: We obtained 1188 pharyngeal cultures from 283 healthy children, 18 to 59 months of age; 51 children had received unconjugated polysaccharide vaccine (PRP), and 89 had received conjugate vaccine (94% PRP-diphtheria toxoid). MEASUREMENTS AND RESULTS: Multivariate analysis was used to test the possibility of an association between vaccination status and the rate of colonization with H. influenzae type b. Among children known to be exposed to at least one child with a positive culture result, the efficacy of conjugate vaccination to prevent H. influenzae type b colonization in an unmatched analysis was 64% (95% confidence interval: 5%, 86%; p = 0.02) and in a matched analysis 81% (95% confidence interval: 7%, 96%; p = 0.02). No effect on colonization was found with PRP vaccination. CONCLUSIONS: Conjugate vaccination decreases H. influenzae type b pharyngeal colonization and thereby may decrease transmission of this agent among healthy children.

Bacterial Proteins↗
PubMed1992

Segmental systolic responses to brief ischemia and reperfusion in the hypertrophied canine left ventricle.

OBJECTIVES AND BACKGROUND: Left ventricular hypertrophy is associated with increased mortality, increased myocardial infarct size and an increased incidence of sudden death. Although reperfusion after ischemia has been shown to result in decreased infarct size and recovery of systolic thickening, it is unknown how left ventricular hypertrophy might influence recovery of regional systolic thickening after ischemia and reperfusion. We hypothesized that left ventricular hypertrophy might attenuate or abolish the functional response to reperfusion. METHODS: Three groups of chronically instrumented, conscious dogs (dogs with left ventricular hypertrophy and hypertension; dogs with left ventricular hypertrophy and reduced blood pressure and a control group without hypertrophy and with normal blood pressure) underwent 15 min of ischemia and 24 h of reperfusion. Segmental systolic thickening was measured by sonomicrometers and myocardial segments were grouped by percent of control segmental systolic thickening retained at 15 min of ischemia (class 1 greater than or equal to 67%, class 2 from 0% to 66%, class 3 less than 0% control systolic thickening). The recovery of each class of segment was measured serially during reperfusion. Hemodynamic variables and regional myocardial blood flow were also measured. RESULTS: There were no differences among groups in recovery of segmental systolic thickening for class 1 segments. Systolic thickening in class 2 (hypokinetic) segments was significantly depressed (p less than 0.05 compared with control value) in the group with left ventricular hypertrophy and reduced blood pressure (but not in the group with hypertrophy and hypertension) during early reperfusion; systolic thickening in class 3 (dyskinetic) segments showed a similar trend in the group with hypertrophy and reduced pressure. CONCLUSIONS: Although left ventricular hypertrophy with hypertension did not attenuate the contractile response to reperfusion, hypertrophy with reduced blood pressure was associated with significantly greater depression of segmental systolic thickening early during reperfusion.

Animals↗
PubMed1992

Invasive Haemophilus influenzae type b disease in children less than 5 years of age in Minnesota and in Dallas County, Texas, 1983-1984.

During 1983 and 1984, 733 cases of invasive Haemophilus influenzae type b disease in children less than 5 years of age were identified in Minnesota and in Dallas County, Texas. The overall incidence of disease was lower in Minnesota than in Dallas County. However, among urban residents, the rates of disease for whites were similar in the two areas. A higher rate of disease among whites in urban Minnesota compared with rural Minnesota resulted from an increased rate of cases for diagnoses other than meningitis. Local practices might have affected the rate of certain diagnoses, since ascertainment of Hib disease other than meningitis is more dependent on diagnostic practices than is diagnosis of meningitis. These data suggest that the incidence of invasive H. influenzae type b disease is influenced by the racial composition of the population, the rates of disease in specific subgroups, and possibly by local medical practices. Understanding the factors that contribute to the incidence of disease is necessary to interpret variations in different populations and changes over time.

Age Factors↗