PubMed HealthSearch

Biomedical subjects

F Fuentes

Publications and source records attributed to F Fuentes.

At least 19 recordsLinked to original sources

Vertebral fractures associated with osteoporosis: patient management.

With the growing interest in new treatments aimed at preventing bone loss and conserving bone mass, insufficient attention has been given to symptomatic treatment of patients with vertebral fractures. Patients often believe that the pain and impaired mobility associated with these fractures are permanent and that little can be done to help. This is a serious misconception. Prompt intervention using a multidisciplinary approach can hasten recovery from pain; improve mobility, flexibility, and speed of movement; and restore independence. Individualized care is needed because clinical features and degree of physical disability vary widely. Asymptomatic patients with vertebral fractures require evaluation and a management plan aimed at maintaining bone mass, improving functional status of the affected region, and preventing pain and new fractures. For patients with acute or chronic pain, treatment of pain and functional limitations is the first priority, followed by functional rehabilitation and preservation of bone mass. A multidisciplinary approach to long-term care is recommended and includes lifestyle re-education, physical therapy, physical fitness training, neurologic and orthopedic evaluation, and, for some patients, use of an orthosis. After 4-6 weeks, those patients for whom pain is persistent require detailed study to detect neurologic, myofascial, or orthopedic complications that can lead to chronic impairment of mobility. Vertebroplasty, surgery using different modalities, new exercise programs, and lifestyle modifications, together with more potent and effective medications to improve bone quality, are options to be used in the individual patient. Well-designed studies are needed that specifically examine the management of these patients, particularly in the areas of pain relief and functional rehabilitation.

Female

In vivo and in vitro study of several pharmacodynamic effects of meropenem.

Several pharmacodynamic parameters are being studied and applied to the design of dosage regimens. The thigh infection model in neutropenic mice has been used in this study to investigate the in vivo postantibiotic effect (PAE) of meropenem against S. aureus, E. coli and P. aeruginosa. The sub-minimum inhibitory concentration (sub-MIC) postantibiotic effect (PA SME) of 1/2, 1/4 and 1/8 x MIC was also determined in vitro on S. aureus and E. coli after pre-exposure of these microorganisms to 10 x MIC of meropenem. The in vitro PAE was also determined. In vivo killing curves using 2 different short dosage regimens were also studied to relate the lethal effect to the time that serum levels were above the MIC. No significant in vivo and in vitro PAEs were observed. The PA SMEs were higher for S. aureus than for E. coli. The 2 short dosage regimens, in vivo, were equally effective in killing S. aureus, but not E. coli. These results suggest that the pharmacodynamics of meropenem on Gram-negative strains may need further study to elucidate the mechanisms and characteristics of these parameters. On the other hand, we need to standardize a reliable in vitro method to monitor regrowth with a good correlation with the in vivo conditions.

Animals

Changes in cognitive and language functioning of preschool children with autism.

Preschool children with autism and their normally developing peers were compared on the Stanford-Binet IV and Preschool Language Scale before and after 1 school year. Both measures showed that although the children with autism functioned at a lower level than their normally developing peers, the children with autism had narrowed this gap after treatment, making a nearly 19-point increase in IQ and an 8-point gain in language quotient. The IQ measure remained stable for the normally developing peers while their language showed a 7.73-point increase. The data support the notion that young children with autism can make very significant developmental gains.

Autistic Disorder

Measurements of glycosaminoglycans in follicular, oviductal and uterine fluids of mares.

Eighteen fertile mares were used to determine the effects of the oestrous cycle and location in the reproductive tract on the amount and concentration of glycosaminoglycans in luminal fluids. Ovariohysterectomies were performed in 3 groups of 6 mares on Day 3 of behavioural oestrus, within 6 h after ovulation or on Day 8 of dioestrus. The lumina of the uterine horns and oviducts ipsilateral and contralateral to the active ovary were flushed and fluid was aspirated from the dominant follicle in the oestrous preovulation group. Glycosaminoglycans and protein concentrations were measured in these fluids. Both the total amount and the concentration of glycosaminoglycans were higher in the pre- and post ovulatory oestrous groups than in the dioestrous animals and they were higher in the luminal fluids than in oviductal fluids. There were no significant differences between the ipsilateral and contralateral sides of the reproductive tract and the concentration of glycosaminoglycans in follicular fluid was far greater than in other parts of the tract. The increased quantity and concentrations of glycosaminoglycans found in the tubular reproductive tract of mares during the follicular phase of the oestrous cycle supports the hypothesis that these molecules may play a role in events associated with fertilization.

Animals

Ethanol alters vasoactive intestinal peptide-induced steroid release from immature rat ovaries in vitro.

The present study was conducted to examine the acute effects of ethanol (ETOH) on basal and VIP-induced release of testosterone (T) and estradiol (E2) from immature ovaries in vitro. Ovaries were collected from anestrus (A) and both naturally occurring and pregnant mare's serum gonadotropin (PMSG)-induced early proestrus (EP) animals. The ovaries were incubated in either media alone, media plus 1 microM VIP, media plus ETOH in doses ranging from 25 to 100 mM, or media plus each dose of ETOH containing VIP. The present results demonstrate that ETOH did not affect either basal or VIP-induced steroid release from ovaries collected from A animals. Likewise, the ETOH did not alter basal steroid secretion from EP animals; however, the drug significantly reduced the VIP-stimulated release of both T and E2 from EP ovaries. Thus, these data demonstrate for the first time that ETOH is capable of altering prepubertal ovarian responsiveness to VIP, a peptide known to be involved in the developmental regulation of ovarian function.

Animals

Improved infarct-related arterial patency after high dose, weight-adjusted, rapid infusion of tissue-type plasminogen activator in myocardial infarction: results of a multicenter randomized trial of two dosage regimens.

To determine whether a weight-adjusted high dose (2 mg/kg body weight over 3 h) rapid infusion of recombinant tissue-type plasminogen activator (rt-PA) was more efficacious than a weight-adjusted standard dose (1.25 mg/kg over 3 h) in achieving reperfusion in the setting of acute myocardial infarction, 175 patients were entered into a randomized multicenter trial. Eighty-four patients were entered into the high dose group, receiving 1.2 mg/kg (10% given as a bolus injection) over 1 h, followed by 0.8 mg/kg over the next 2 h. Ninety-one patients were given 0.75 mg/kg (10% given as a bolus injection) in 1 h, followed by 0.5 mg/kg administered over the next 2 h. The median dose in the group that received 2 mg/kg dose was 145 mg, compared with 100 mg in the group that received 1.25 mg/kg. The 90 min patency rate in the group that received 2 mg/kg was 84% compared with 70% in the group that received 1.25 mg/kg (p = 0.003). Sixty-four percent of the patients in each group underwent coronary angioplasty at the time of cardiac catheterization. The infarct-related artery patency rate at the end of catheterization was 91% in the group that received 2 mg/kg compared with 83% in the group that received 1.25 mg/kg (p = 0.08). Among patients with a patent infarct-related coronary artery after catheterization, the 6 month mortality rate in the group that received 2 mg/kg was 2.9% compared with 9.8% in the group that received 1.25 mg/kg (p = 0.15). The bleeding complication rate in the two groups was similar.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Blunt chest trauma. Extrapericardial cardiac tamponade by a mediastinal hematoma.

Mediastinal hematoma resulting from blunt chest trauma can cause compression of the right ventricle and extrapericardial cardiac tamponade. The diagnosis in this instance was aided by conventional two-dimensional echocardiography in addition to hemodynamic measurements. The atypical aspects of this form of cardiac tamponade are discussed.

Cardiac Tamponade

Vasodilators and primary pulmonary hypertension. Variability of long-term response.

Long-term response to vasodilator therapy was assessed in six patients with PPH. Following an acute trial, each patient was restudied after (1) two months of drug administration, (2) one month of abstinence from therapy, and (3) an additional two months of therapy. Three of six patients had no long-term reduction of PVR after treatment; one showed a progressive increase. Of the three patients whose PVR was still reduced at the end of the second therapy period none showed a return of PVR to baseline during the abstinence phase, which may suggest that long-term reduction of pulmonary vascular tone may modify the vasoconstrictive component of this disease. The heterogeneous response of this small number of patients to sequential drug administration and withdrawal demonstrates the difficulty of interpreting previously reported clinical trials and underscores the need for a well-designed controlled study of vasodilator administration in these patients.

Adult

[Operations research in group feeding programs: techniques for the identification and analysis of management problems].

The operations of the group feeding programs (PAG--"Programas de Alimentación a Grupos"--) can be viewed as a sequence of decisions and activities that according to their direction, order, relationship and dependency, will influence the quality and quantity of the service's delivery. While searching for the essential characteristics of a PAG: components, relationship, variables, pertinent parameters, restrictions, underlying criteria and objective functions, operations research can be useful for its analysis, the identification of its management problems, and to develop, evaluate and finally, implement solutions. Various operation research techniques are presented in this article, which are geared towards responding to those knowledge needs of the national technicians and program managers, in order to give a solid foundation to solutions for the management problems identified in a PAG. Failures of different quantitative models had been due, mainly, to the tendency to formulate models or investigate problems without users being prepared to implement the solutions. The techniques presented herein take into consideration the interaction between specialists and users.

Food Services

Factors affecting outcome of coronary reperfusion with intracoronary streptokinase in acute myocardial infarction.

Aggressive interventional therapy in acute myocardial infarction (AMI) is expensive, time-consuming and not without significant risk. To determine which patients are most likely to benefit from such therapy, the effects of patient age, reperfusion success, admission left ventricular (LV) function, infarct location, admission clinical class, time from onset of pain to reperfusion and admission electrocardiographic findings on the outcome of coronary reperfusion in AMI were assessed in 292 prospectively studied, sequential patients from August 1980 to January 1984. Two hundred ten patients received intracoronary streptokinase (SK) therapy on admission and 82 patients, who either refused the protocol or met exclusion criteria, served as control subjects. Patients older than 65 years showed little improvement in 1-year mortality risk and no significant improvement in LV function during hospitalization after treatment with intracoronary SK. The remaining patients, 178 treated with SK and 48 control, were well matched and served as the basis for further comparisons. In this subgroup of patients, reperfusion success was associated with improved survival and LV function (mortality rate 3%, vs 17% in control subjects; increase in ejection fraction [EF] 18% vs 4%). Patients with an EF of less than 45% on admission showed a 21 +/- 30% increase in EF, compared with an increase in control subjects of 8 +/- 19%, and a lower 1-year mortality rate than controls (6% vs 21%, p = 0.01). Patients with anterior AMI had a significant increase in EF in the SK group (22 +/- 31%) and lower mortality compared with control subjects (5% vs 25%, p = 0.003).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Successful aortocoronary bypass in osteogenesis imperfecta.

Cardiovascular abnormalities are infrequently documented in osteogenesis imperfecta, one of a group of hereditary, generalized connective tissue disorders. A patient with osteogenesis imperfecta is described with mitral valve prolapse, significant coronary artery disease and a coronary artery aneurysm. The latter two cardiac defects are apparently rare in this disease. The option of surgery was carefully considered with regard to technical feasibility and potential deterioration of the graft anastomoses. Although successful aortocoronary bypass surgery had not been previously reported in osteogenesis imperfecta, this patient received such surgery with therapeutic benefit. Therefore, coronary artery vascularization should be considered as a safe and effective treatment modality for patients with osteogenesis imperfecta and coexisting coronary atherosclerosis.

Adult

Comparison of progressive exercise performance of normal subjects and patients with primary pulmonary hypertension.

The extent of exercise limitation and the mechanisms for that limitation in 11 patients with primary pulmonary hypertension (PPH) were studied by progressive, upright cycle ergometry. All patients had a mean pulmonary artery pressure of 30 mm Hg or higher (mean, 56 +/- 15), normal pulmonary function testing, normal pulmonary capillary wedge pressure, and pulmonary angiography consistent with the diagnosis. Rest and exercise data obtained from the patients with PPh were compared with data obtained from 11 matched, sedentary control subjects. Mean maximal oxygen consumption (VO2) was 13 +/- 4 ml/kg/min in the PPH group compared with 28 +/- 7 ml/kg/min in the controls. At maximal VO2 the minute ventilation (VE) was similar; however, the VE at any level of carbon dioxide production (VCO2) during rest and exercise was significantly higher in the PPH group. Maximal heart rate and oxygen pulse (VO2/heart rate) was significantly higher in the control group (148 +/- 18 vs 180 +/- 24, and 6.3 +/- 2.2 vs 9.9 +/- 3.9, respectively). Anaerobic threshold occurred earlier during progressive exercise in the PPH group and correlated positively with the maximal oxygen pulse achieved in patients with PPH. In conclusion, patients with PPH have severe exertional limitation due to cardiovascular factors with an inability to maintain appropriate oxygen delivery to the body during exercise. No respiratory impairment was recognized; however, an exaggerated ventilatory response to exercise at any level of VCO2 was found.

Adult

Aortic root abscess. Initial experience using magnetic resonance imaging.

The detection of aortic root abscess by magnetic resonance imaging has not been described previously. We report a patient with an aortic root abscess that was successfully diagnosed by magnetic resonance imaging and echocardiography. Computed tomography failed to detect the abscess. The patient recovered with antibiotic therapy. Based on this case and other reports in the literature, we advocate treating similar patients without surgery. We recommend magnetic resonance imaging as an investigational method where the diagnosis of aortic root abscess is ambiguous.

Abscess

Positron imaging of myocardial infarction with rubidium-82.

Positron imaging provides tomographic images of regional myocardial perfusion but has required an on-site cyclotron. Rubidium-82 (82Rb) is a short-lived (T1/2 = 75 sec) positron emitter available from a generator. In order to determine the feasibility for its use to image acute myocardial infarction, 18 patients with transmural infarctions who had coronary arteriography were given 30-40 mCi of 82Rb intravenously and positron tomographic imaging was carried out within 96 hr after onset of symptoms. Nine simultaneous transaxial slices were obtained for each patient with a positron camera. Images were also reconstructed in a long-axis, short-axis, and three-dimensional display. One study could not be interpreted because of excessive lung activity. Fourteen normals were also studied. The infarct related artery determined by angiography was correctly diagnosed by positron imaging in all 17 patients as were all three prior infarcts by readers blinded to the clinical data. No defects were observed in normals or in noninfarcted myocardial regions. This study indicates that 82Rb should be useful for perfusion imaging in patients with acute myocardial infarction. The short half-life of 82Rb should make it ideal for providing serial assessment of perfusion in patients undergoing thrombolytic therapy.

Acute Disease