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J Gonzales

Publications and source records attributed to J Gonzales.

At least 19 recordsLinked to original sources
PubMed2001

[Influence of age and physical activity on isokinetic characteristics of hamstring and quadriceps muscles of young gymnasts and soccer players].

OBJECTIVE: The aim of this work is the assessment of age and sport influences on the isokinetic knee muscle characteristics. SUBJECTS AND METHOD: Subjects performed a bilateral knee flexion/extension test on an isokinetic device at 60 and 180 degrees.s(-1) speed in concentric mode. The three parameters studied in this work were the Peak Torque, Average Power and hamstring/quadriceps ratio. Thirty-eight soccer players (16,6 +/- 1.4 years old) and 22 gymnasts (18 +/- 2.8 years old) were tested. The population was separated into three groups : 15 years old, 17 years old, 20 years old. RESULTS: The isokinetic values of soccer players were significantly higher (p < 0.0001) than those of the the gymnasts. The isokinetic values of the oldest soccer players were significantly higher (0.005 < p < 0.05) for hamstrings than those of the younger soccer players. The isokinetic values of the oldest gymnasts were significantly higher (0.005 < p < 0.05) for the quadriceps than those of the younger gymnasts. There were no significant differences between dominant and non dominant limbs in soccer players. CONCLUSION: In the present study, the muscular maturation improves the absolute strength of the older sportsmen in comparison to the younger. Soccer favor most the absolute strength of the inferior member in comparison to the gymnastics.

Adult↗
PubMed2001

Long-term treatment of obsessive-compulsive disorder after an acute response: a comparison of fluoxetine versus placebo.

Few controlled studies have evaluated the long-term continuation of pharmacotherapy for relapse prevention in patients with obsessive-compulsive disorder (OCD). This study assessed efficacy and safety of fluoxetine versus placebo in preventing relapse of OCD during a 52-week period in responders to short-term administration of fluoxetine. Patients who met DSM-IV criteria for OCD and had a Yale-Brown Obsessive Compulsive Scale score > or = 19 were treated with single-blind fluoxetine 20, 40, or 60 mg/day (based on physician assessment of response and tolerability). After 20 weeks, responders were randomly assigned to receive continued treatment with fluoxetine or placebo and were monitored for relapse for up to 52 weeks. Of 130 patients who entered the study, 71 (55%) were randomly assigned to receive fluoxetine (N = 36) or placebo (N = 35). Patients who received fluoxetine had numerically lower relapse rates compared with those who received placebo, although the difference was not significant (Kaplan-Meier 1-year relapse rates: fluoxetine, 20.6%; placebo, 31.9%; one-tailed p value = 0.137). In additional analyses evaluating patients on the basis of fluoxetine dose at randomization, patients who continued treatment with fluoxetine 60 mg/day (N = 52) had significantly lower rates of relapse than those who were switched to placebo (Kaplan-Meier 1-year relapse rates: fluoxetine, 17.5%; placebo, 38.0%; one-tailed p value = 0.041). Those who responded to the acute treatment phase with 40 (N = 18) or 20 (N = 1) mg/day had low overall rates of relapse, and the difference between continued fluoxetine and placebo treatment for these patients was not significant. For responders to the 60 mg/day dosage, those patients who continued treatment with fluoxetine were provided greater protection against relapse than those patients switched to placebo.

Adolescent↗
PubMed2000

Differential vulnerability of primary cultured cholinergic neurons to nitric oxide excess.

Many neuronal nitric oxide synthase (nNOS)-expressing brain neurons, including some cholinergic populations, are resistant to disease or to certain forms of excitotoxicity. Vulnerability to NO excess of forebrain (medial septal/diagonal band; MS-ACh) and brainstem (pedunculopontine/laterodorsal tegmental nuclei; BS-ACh) cholinergic neurons was compared in E16-E18 primary rat brain cultures. MS-ACh cells were approximately 300-fold more sensitive to the NO donor S-nitro-N-acetyl-D,L-penicillamine (SNAP) than were BS-ACh cells. Most (69%) MS-ACh cells contained nuclear DNA fragments by 2 h after addition of SNAP, while only 21% BS-ACh cells were TUNEL-positive after NO excess. Depletion of glutathione content did not potentiate the effect of SNAP on MS-ACh cells, but sensitized BS-ACh cells to the NO donor. Caffeic acid, a putative NF-kappa B inhibitor, enhanced the toxicity of SNAP to cholinergic neurons in both preparations. Our experiments show that cholinergic neurons in mixed primary cultures from different brain regions possess biochemical differences with respect to their vulnerability to NO excess.

Acetylcholine↗
PubMed1999

Multiple vasodilator pathways from the pelvic plexus to the penis of the rat.

The main penile or cavernous nerve is usually regarded as the most important vasodilator projection in the rat. Although other descending pathways have been described, there is little detailed information on their importance. In this present report, we provide topographic and quantitative information on lateral and ventral penile branches and examine the vasodilator fibers which join the pudendal neurovascular bundle. Seventeen Sprague-Dawley rats were used. The techniques included injection of dye in the penis to label neurons in the pelvic plexus in combination with transection of the main penile nerve (MPN). NADPH diaphorase (NADPH-d) histochemistry was used to assess the effects of transection of vasodilator pathways on innervation of the penis and for in situ staining of the pelvic plexus. Distinct clusters of penile neurons are aggregated at the origin of several nerve tracts leaving the posterior margin of the major pelvic ganglion (MPG). Multiple NADPH-d+ fiber bundles coursed over the anterior surface of the prostate to reach the penis. Branches from these tracts joined the pudendal neurovascular bundle proximal to the hilum of the penis and provided innervation to the artery throughout its course in the pudendal canal. Consistent with the presence of multiple penile pathways, transection of the MPN reduced, but did not eliminate retrograde labeling of penile neurons in the MPG and only modestly decreased NADPH-d+ fibers in the penis. This study confirms that there are multiple pathways by which vasodilator fibers reach the penis. If a similar allocation of vasodilator output is present in man, preservation of finer branches of the pelvic plexus would be important in surgical procedures on the prostate.

Animals↗
PubMed1999

Hormonal regulation and cellular localization of fatty acid synthase in human fetal lung.

Fatty acid synthase (FAS; EC 2.3.1.85) supplies de novo fatty acids for pulmonary surfactant synthesis, and FAS gene expression is both developmentally and hormonally regulated in the fetal lung. To further examine hormonal regulation of FAS mRNA and to determine the cellular localization of FAS gene expression, we cultured human fetal lungs (18-22 wk gestation) as explants for 1-4 days in the absence (control) or presence of glucocorticoid [dexamethasone (Dex), 10 nM] and/or cAMP agents (8-bromo-cAMP, 0.1 mM and IBMX, 0.1 mM). FAS protein content and activity increased similarly in the presence of Dex (109 and 83%, respectively) or cAMP (87 and 111%, respectively), and responses were additive in the presence of both hormones (230 and 203%, respectively). With a rabbit anti-rat FAS antibody, FAS immunoreactivity was not detected in preculture lung specimens but appeared in epithelial cells lining the tubules with time in culture. Dex and/or cAMP markedly increased staining of epithelial cells, identified as type II cells, whereas staining of mesenchymal fibroblasts was very low under all conditions. With in situ hybridization, FAS mRNA was found to be enriched in epithelial cells lining the alveolar spaces, and the reaction product increased in these cells when the explants were cultured with the hormones. The increased FAS mRNA content in the presence of Dex and/or cAMP is primarily due to increased stabilization of mRNA, although Dex alone increased the transcription rate by approximately 30%. We conclude that hormonal treatment of cultured human fetal lungs increases FAS gene expression primarily by increasing stability of the message. The induction of FAS during explant culture and by hormones occurs selectively in type II epithelial cells, consistent with the regulatory role of this enzyme in de novo synthesis of fatty acid substrate for surfactant synthesis in perinatal lungs.

Drug Stability↗
PubMed1998

Preganglionic fibers in the rat hypogastric nerve project bilaterally to pelvic ganglia.

Stimulation of the hypogastric nerve (HGN) often evokes bilateral responses in some pelvic organs. Retrograde labeling studies indicate that axons of postganglionic neurons often cross to the opposite side. However, there is little information available as to whether preganglionic fibers in the HGN have a contralateral projection to pelvic ganglia. A retrograde tracer was injected into the left major pelvic ganglion (MPG) in rats receiving various lesions of preganglionic nerves (HGN and pelvic nerve, PN). The lumbar spinal cord was then examined for location and number of dye-filled neurons. In a second approach, the incidence of synaptophysin immunoreactivity (SN-IR) perineuronal profiles (baskets) was examined in the MPG and in the accessory pelvic ganglia (APG) after nerve lesions. Labeled neuronal profiles were found in spinal cord nuclei (Lumbar1-2) after dye injection of the MPG in animals with an intact contralateral HGN. Cutting both HGNs virtually eliminated dye labeling in the lumbar cord, as did severing commissural branches (CB) between pelvic ganglia (leaving the contralateral HGN intact). Some SN-IR baskets were found in the left APG when only the contralateral HGN was intact, but baskets were rare when all four preganglionic nerves were cut. It could not be determined whether the HGN projects to the contralateral MPG, since SN-IR baskets were numerous in the MPG even when all four nerves were cut. This study has shown that some preganglionic fibers in the HGN synapse on neurons in contralateral pelvic ganglia. Both the APG and MPG receive contralateral innervation, but it is likely that neurons in the APG are the primary target of this input. Thus, in addition to crossing postganglionic fibers, a portion of the bilateral control of pelvic tissues is accomplished by preganglionic fibers which target autonomic neurons in contralateral ganglia.

Animals↗
PubMed1998

Increasing access to child mental health services for urban children and their caregivers.

This article presents the results of a study that evaluated the effects of two engagement interventions on the initial attendance and ongoing retention in child mental health services of 109 primarily children of color and their families. Both the combined intervention (telephone and first interview) and the telephone-alone intervention were associated with significant increases in attendance at initial intake appointments over the usual intake procedure, but only the combined intervention was related to the greater ongoing use of services. Implications for future research and recommendations for modifying procedures in outpatient child mental health centers are also presented.

Adolescent↗
PubMed1998

The laryngeal mask airway reliably provides rescue ventilation in cases of unanticipated difficult tracheal intubation along with difficult mask ventilation.

UNLABELLED: In 1995, our department of anesthesiology established an airway team to assist in treating unanticipated difficult endotracheal intubations and an airway quality improvement (QI) form to document the use of emergency airway techniques in airway crises (laryngeal mask airway [LMA], flexible fiberoptic bronchoscopy, retrograde intubation [RI], transtracheal jet ventilation [TTJV], and cricothyrotomy). Over a 2-yr period, team members and staff anesthesiologists completed airway QI forms to document the smallest peripheral SpO2 during an airway crisis, the number of direct laryngoscopies (DL) performed before using an emergency airway technique, and the emergency airway technique that succeeded in rescue ventilation. Team members agreed to use the LMA as the first emergency airway technique to treat the difficult ventilation/difficult intubation scenario. A SpO2 value < or =90% during mask ventilation defined difficult ventilation. Inability to perform tracheal intubation by DL defined difficult intubation. An increase in the SpO2 value >90% defined rescue ventilation. Review of airway QI forms from October 1, 1995 until October 1, 1997 revealed 25 cases of difficult ventilation/difficult intubation. Before airway rescue, the median SpO2 was 80% (range 50%-90%), and there were four median attempts at DL (range one to nine). The LMA had a success rate of 94% (95% confidence interval [CI] 77-100). Flexible fiberoptic bronchoscopy, TTJV, RI, and surgical cricothyrotomy had success rates of 50% (95% CI 0-100), 33% (95% CI 0-100), 100% (95% CI 37-100), and 100% (95% CI 37-100), respectively. LMA insertion as the first alternative airway technique was useful in dealing with unanticipated instances of simultaneous difficulty with mask ventilation and tracheal intubation. IMPLICATIONS: Twenty-five cases of simultaneous difficulty with mask ventilation and tracheal intubation occurred after the induction of general anesthesia during the study period. The laryngeal mask was used in 17 cases, and it provided rescue ventilation without complication in 94% of these cases (95% confidence interval 77-100).

Anesthesia↗
PubMed1998

Prevalence of astroviruses in a children's hospital.

An enzyme immunoassay for astrovirus was used to screen 357 stool samples from 267 symptomatic inpatients at a tertiary-care children's hospital. Thirty stool samples from 26 patients contained astrovirus antigen, while rotavirus was found in 34 samples and Clostridium difficile toxin was found in 40. Half of the astrovirus infections were nosocomial. Additional pathogens were identified in six of the astrovirus antigen-positive stool samples. Most (80%) of the astroviruses recovered were of serotype 1. Astrovirus infections were significantly more common than rotavirus or C. difficile infections in very young infants and in those with surgical short-bowel syndrome.

Adolescent↗
PubMed1997

Cytochrome oxidase staining in the major pelvic ganglion of the male rat.

Cytochrome oxidase staining was used as a marker of metabolic activity in neural elements in the rat major pelvic ganglion. Many neurons in the ventral pole of the ganglion have little cytochrome oxidase activity, while neurons in other locations show gradations in staining intensity. Punctate staining around principal neurons may represent preganglionic terminals, since it was greatly reduced after denervation of the ganglion. Image analysis was used to compare neuronal size to staining intensity. There was a negative correlation between cell size and staining intensity; the largest neurons were only lightly stained for cytochrome oxidase, while the medium and the small neurons showed a full range of metabolic activity. To study metabolic activity of an identified neuronal population, the seminal vesicles were injected with a retrograde tracer. The largest seminal vesicles neurons (1500 to 3200 microns2) had low enzyme activity, whereas the majority of neurons to this organ were smaller with gradations in staining. These results are indicative of the metabolic activity of the autonomic innervation to various pelvic tissues. Cytochrome oxidase histochemistry should prove valuable in assessing the demands placed on autonomic ganglia in differing functional and dysfunctional states.

Animals↗
PubMed1997

Cost-effectiveness of newer antidepressants compared with tricyclic antidepressants in managed care settings.

BACKGROUND: Our aim was to determine the cost-effectiveness of newer antidepressants compared with tricyclic antidepressants in managed care organization settings. METHOD: We employed cost-utility analysis based on a clinical decision analysis model derived from published medical literature and physician judgment. The model, which represents ideal primary care practice, compares treatment with nefazodone to treatment with either imipramine or fluoxetine or to a step approach involving initial treatment with imipramine followed by nefazodone for treatment failures. The outcome measures were lifetime medical costs, quality-adjusted life years (QALYs), and costs per QALY gained. RESULTS: The base case analysis found that nefazodone treatment had $16,669 in medical costs, compared with $15,348 for imipramine, $16,061 for the imipramine step approach, and $16,998 for fluoxetine. QALYs were greatest for nefazodone (14.64), compared with 14.32 for imipramine, 14.40 for the step approach, and 14.58 for fluoxetine. The cost-effectiveness ratio comparing nefazodone with imipramine was $4065 per QALY gained. The cost-effectiveness ratio comparing nefazodone with the step approach was $2555 per QALY gained. There were only minor differences in costs and outcomes between nefazodone and fluoxetine, with nefazodone resulting in $329 fewer costs and 0.06 more QALYs. The cost-effectiveness ratios comparing fluoxetine with imipramine and with the step approach were $6346 per QALY gained and $5206 per QALY gained, respectively. In the sensitivity analyses, the cost-effectiveness ratios comparing nefazodone and imipramine ranged from $2572 to $5841 per QALY gained. The model was most sensitive to assumptions about treatment compliance rates. CONCLUSION: The findings suggest that nefazodone is a cost- effective treatment compared with imipramine or fluoxetine treatment for major depression. Fluoxetine is cost-effective compared with imipramine treatment, but is estimated to have slightly more medical costs and less effectiveness compared with nefazodone. The basic findings and conclusions do not change even after modifying key model parameters.

Antidepressive Agents↗
PubMed1996

Prenatal diagnosis of Roberts syndrome: two new cases.

We report two fetuses with typical anomalies of Roberts syndrome. Prenatal diagnosis was confirmed by the characteristic disjunction of centromeres in amniocytes. We compare these cases with a child who presented with severe Roberts syndrome. We attempted to evaluate quantitatively the centromeric abnormality and the chromosome separation in the different cultures and with different methods. The variability of the clinical manifestations and cytogenetic investigations of this syndrome are reviewed.

Adult↗
PubMed1996

Surgical management of brachioaxillary-subclavian vein occlusion.

OBJECTIVE: The possibility of using RING PTFE graft as venous bypass to preserve arteriovenous graft function and reduce upper extremity swelling. METHODS: Twenty-two patients with stenosis/occlusion of the brachial-axillary-subclavian vein segment in haemodialysis patients (n = 19) and patients with penetration injury (n = 3) who were not candidates for balloon angioplasty were treated with ring PTFE venous bypass in renal patients and jugular to axillary vein transposition for trauma patients and followed for 10-87 months (mean 31) using venography, Doppler analysis and Duplex scanning. RESULTS: There was no death or neurologic deficit resulting from the venous bypass. Resolution of swelling occurred in 8-48 h. 19/22 (86%) of the bypasses and 3/3 transpositions remained patent after a mean follow-up of 31 months (10-87) months. The attrition was due to AV graft occlusion (n = 2) and infection requiring graft removal (n = 1). CONCLUSIONS: Ring PTFE graft is an acceptable venous bypass for brachial-axillary-subclavian stenosis/occlusion to reduce arm swelling and preserve the function of AV grafts in patients with lesions not amendable with balloon angioplasty or thrombolytic therapy. Jugular-axillary transposition is inappropriate for renal patients.

Adult↗
PubMed1996

Transcriptional regulation of human pulmonary surfactant proteins SP-B and SP-C by glucocorticoids.

Expression of the pulmonary surfactant-associated proteins SP-B and SP-C is under both developmental and hormonal regulation. We used human fetal lung to investigate developmental changes and the mechanism of glucocorticoid stimulation of SP-B and SP-C gene expression. There were similar approximately 3-fold increases in SP-B cytoplasmic mRNA content and transcription rate comparing lung samples of 24 wk versus 16 wk gestation. During 5 days of lung explant culture without hormones, the transcription rate increased for SP-B and decreased for SP-C, paralleling changes in mRNA content. Treatment with 100 nM dexamethasone maximally increased transcription of the SP-B gene (approximately 3-fold) and SP-C gene (approximately 11-fold) after 2 and 8 h, respectively, similar to changes in mRNA content. In dose-response studies, the maximal increase in transcription rate occurred at approximately 10 nM dexamethasone for SP-B and at > or = 100 nM for SP-C. Induction of SP-B mRNA content and transcription rate were not affected by prior cycloheximide exposure, whereas induction of SP-C mRNA was decreased by as little as 1 h exposure to inhibitor. We conclude that glucocorticoids, acting directly in type II cells, regulate the SP-B and SP-C genes primarily at the level of transcription. Induction of SP-C, but not SP-B, requires ongoing protein synthesis which likely reflects involvement of a labile transcription factor. The difference in glucocorticoid sensitivity may indicate that the two surfactant protein genes contain glucocorticoid response elements with different affinities for receptor.

Anti-Inflammatory Agents↗
PubMed1995

A short-term study of the safety, pharmacokinetics, and efficacy of ritonavir, an inhibitor of HIV-1 protease. European-Australian Collaborative Ritonavir Study Group.

BACKGROUND: Reverse-transcriptase inhibitors have only moderate clinical efficacy against the human immunodeficiency virus type 1 (HIV-1). Ritonavir is an inhibitor of HIV-1 protease with potent in vitro anti-HIV properties and good oral bioavailability. METHODS: We evaluated the antiviral activity and safety of ritonavir in a double-blind, randomized, placebo-controlled phase 1 and 2 study of 84 HIV-positive patients with 50 or more CD4+ lymphocytes per cubic millimeter. The patients were randomly assigned to one of four regimens of ritonavir therapy, or to placebo for four weeks and then (by random assignment) to one of the ritonavir regimens. RESULTS: During the first 4 weeks, increases in CD4+ lymphocyte counts and reductions in the log number of copies of HIV-1 RNA per milliliter of plasma were similar among the four dosage groups, but in the three lower-dosage groups there was a return to base-line levels by 16 weeks. After 32 weeks, in the seven patients in the highest-dosage group (600 mg of ritonavir every 12 hours), the median increase from base line in the CD4+ lymphocyte count was 230 cells per cubic millimeter, and the mean decrease in the plasma concentration of HIV-1 RNA (as measured by a branched-DNA assay) was 0.81 log (95 percent confidence interval, 0.40 to 1.22). In a subgroup of 17 patients in the two higher-dosage groups, RNA was also measured with an assay based on the polymerase chain reaction, and after eight weeks of treatment there was a mean maximal decrease in viral RNA of 1.94 log (95 percent confidence interval, 1.37 to 2.51). Adverse events included nausea, circumoral paresthesia, elevated hepatic aminotransferase levels, and elevated triglyceride levels. Ten withdrawals from the study were judged to be related to ritonavir treatment. CONCLUSIONS: In this short-term study, ritonavir was well tolerated and had potent activity against HIV-1, but its clinical benefits remain to be established.

Adult↗
PubMed1995

Magnesium transport induced ex vivo by a pharmacological dose of insulin is impaired in non-insulin-dependent diabetes mellitus.

Diabetes mellitus may be associated with magnesium depletion, which in turn may contribute to metabolic complications of diabetes including vascular disease and osteoporosis. Intracellular depletion is thought to be due to osmotically induced renal magnesium loss; however, impaired ability of insulin to increase intracellular magnesium during insulin deficiency or insulin resistance could also play a role. Magnesium deficiency per se has also been reported to result in insulin resistance. In order to determine if magnesium transport is altered in non-insulin-dependent diabetes mellitus (NIDDM), we measured intracellular Mg(2+) in circulating lymphocytes obtained from nine normal subjects and seven patients with NIDDM. Ionized intracellular Mg(2+) was determined by fluorescent spectroscopy using Mg-fura-2. A 30 min incubation of insulin with lymphocytes obtained from normal subjects resulted in an increase in Mg(2+) of 8.6 +/- 3.6 percent (mean +/- SEM) at 100 mu U/ml which reached a plateau at approximately 250 mu U/ml (11.0 +/- 1.7 percent). The mean lymphocyte Mg(2+) in the patients (0.198 +/- 0.011 mM) was not significantly lower than normal (0.218 +/- 0.017). Insulin (500 mU/ml) added acutely during the fluorescence reading caused a rapid 31 +/- 3.9 percent rise in intracellular Mg(2+) in the normal subjects, which was significantly greater than the 18 +/- 1.6 percent rise observed in the NIDDM subjects (P < 0.01). The effect of magnesium deficiency was also studied in 3 normal subjects experimentally Mg deficient for 3 weeks. The mean lymphocyte Mg(2+) fell from 0.198 +/- 0.009 mM pre-diet to 0.153 +/- 0.006 mM post-diet. and the insulin-induced rise in Mg(2+) fell from 27.2 percent pre-magnesium depletion to 12.7 percent post-magnesium depletion. These data suggest that insulin resistance and magnesium depletion may result in a vicious cycle of worsening insulin resistance and decrease in intracellular Mg(2+) which may limit the role of magnesium in vital cellular processes.

Adult↗