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Biomedical subjects

J Ballester

Publications and source records attributed to J Ballester.

At least 19 recordsLinked to original sources
PubMed2000

Evidence for a functional glycogen metabolism in mature mammalian spermatozoa.

The glycogen content in fresh raw dog spermatozoa was 0.22+/-0.03 micromol/mg protein. This matched with the presence of a glycogen-like staining in the head and midpiece. Glycogen levels lowered to 0.05 micromol/mg protein after incubation for 60 min without sugars. Addition of either 10 mM fructose or 10 mM glucose increased glycogen content to 0.70 micromol/mg protein. On the other hand, glycogen synthase activity ratio of fresh dog sperm (0.35+/-0.07, measured in the absence and the presence of glucose 6-P) increased to 0.55 with 10 mM fructose for 20 min, whereas glucose had a smaller effect. Spermatozoa extracts had also a protein of about 100 Kd, which reacted against a rat liver glycogen synthase antibody. This was located in sperm head and midpiece. Furthermore, glycogen phosphorylase activity ratio measured in presence and absence of AMP (0.25+/-0.03 in fresh samples) decreased to 0.15 by 10 mM glucose for 20 min, whereas fructose was less potent in this regard. The maximal effect of glucose and fructose were observed from 10-20 mM onwards. This work is the first indication for a functional glycogen metabolism in mammal spermatozoa, which could play an important role in regulating sperm survival in vivo.

Animals↗
PubMed1998

Effect of alendronate on cultured normal human osteoblasts.

Alendronate is an aminobisphosphonate with a potent anti-reabsorptive action that does not appear to interfere with bone mineralization, and is even able to increase bone mineral density in osteoporotic postmenopausal women through a still not fully understood mechanism. This study was conducted to assess the direct effect of alendronate on diverse aspects of normal human osteoblast physiology. For that purpose, the in vitro effect of a wide range of concentrations [from 10(-1) to 10(-12) mol/L] of alendronate on cell viability, proliferation, collagen synthesis, and the mineral-depositing capacity of normal human osteoblasts was tested. Alendronate effects were examined at 48 and 96 h of culture in the presence or absence of fetal calf serum. In vitro alendronate affected osteoblast viability at concentrations equal to or higher than 10(-4) mol/L. At concentrations equal to or higher than 10(-3) mol/L, no viable cells were observed in cultures. In vitro alendronate at concentrations between 10(-5) and 10(-12) mol/L did not have any effect on the proliferative capacity of normal human osteoblasts determined by two different techniques: (1) tritiated thymidine incorporation to DNA and (2) cell counting. Collagen synthesis by normal human osteoblasts showed a tendency to decrease following incubation with alendronate supplemented with fetal calf serum. This decrease was only statistically significant after 96 h of culture; however, a dose-response effect could not be documented. Finally, no effect of alendronate was observed on calcium deposition in vitro by normal human osteoblasts at concentrations equal to or lower than 10(-5) mol/L. In conclusion, the present study shows that alendronate in vitro does not affect viability, proliferation, and mineral deposit capacity of normal human osteoblasts at the concentration at which it inhibits by 50% the resorptive capacity of osteoclasts that for this drug has been reported as 2 x 10(-9) mol/L.

Adult↗
PubMed1997

Spinal intraosseous arteriovenous malformation as a cause of juvenile scoliosis. A case report.

STUDY DESIGN: A case report. OBJECTIVES: To report and discuss an unusual case of scoliosis resulting from an arterial malformation of the spine. SUMMARY OF BACKGROUND DATA: This is a report of clinical manifestation, physical findings, computed tomography scan, magnetic resonance imaging, bone scan, and results after surgery in an 8-year-old boy with a painful scoliosis resulting from an intraosseous arteriovenous malformation of the spine. METHODS: Radiographs, computed tomography scan, magnetic resonance imaging, and bone scans were studied and oriented us to the diagnosis of scoliotic attitude secondary to a benign-appearing tumor in the right lamina of L4. Surgery was performed through a posterior midline approach to remove the lesion en bloc. Postoperative treatment was performed with a Boston orthosis. RESULTS: Final pathology reports diagnosed an intraosseous arteriovenous malformation. After 32 months, the boy had no pain, and scoliotic attitude diminished despite radiographs still showing a single 10 degrees right lumbar curve. CONCLUSIONS: Primary intraosseous arteriovenous malformations are rare. This case shows the scarce specificity of clinical findings, radiology, and bone scan in the diagnosis of these lesions when they are localized in vertebral territory. Surgical excision of the lesion relieves pain but does not completely correct the scoliotic attitude.

Arteriovenous Malformations↗
PubMed1997

Osteoblastic proliferation in bone biopsies from patients with end-stage chronic renal failure.

Osteoblasts have traditionally been considered to be terminally differentiated cells and therefore unable to divide. Data in recent years, however, indicate that cellular differentiation does not usually preclude preservation of proliferative ability and that most differentiated cells are able to divide under adequate stimuli. The aim of this study was to assess whether cubic osteoblasts undergo proliferation during the formation phase of the remodeling cycle under a stimulus that increased bone turnover. For that purpose, the osteoblastic proliferation index (OPI) was analyzed by DNA image cytometry in transiliac bone biopsies from 33 patients with chronic renal failure (23 men, 10 women; mean age 50.4 +/- 15.1 years) who have been classified into low (n = 13), normal (n = 15), and high (n = 15) bone turnover according to activation frequency (Ac.f). OPI was significantly higher (p < 0.002) in the high bone turnover group (13.90 +/- 4.72%) compared with the low (2.38 +/- 4.13%) and normal turnover groups (2.84 +/- 4.04%). There was a positive correlation between OPI and the following histomorphometric parameters: bone formation rate, surface referent (r = 0.76, p = 0.00001), activation frequency (r = 0.73, p = 0.00001), mineral apposition rate (r = 0.73, p = 0.00001), bone formation rate, volume referent (r = 0.71, p = 0.00001), and mineralizing surface (r = 0.62, p = 0.0001). This study shows that a rise in bone turnover is associated with a marked increase of bone-forming cell proliferation in patients with end-stage chronic renal failure. From this finding, it may be concluded that cubic osteoblasts do not behave as "terminally differentiated" cells in vivo, because a high proportion of them are still able to divide.

Adult↗
PubMed1995

[Characteristics of AIDS cases detected at a prison in Barcelona (1991-1993)].

OBJECTIVE: To describe the cases of AIDS detected in a Barcelona prison. DESIGN: A prospective study. SETTING: A penitentiary for men in Barcelona. PATIENTS: All those inmates who had AIDS or were diagnosed with the illness during their stay in prison during the 36 months between 1/1/1991 and 31/12/93. RESULTS: 220 cases of AIDS (91.7% PVDA), 60% of which were diagnosed in prison. The PVDA were younger (p < 0.0001). There were a greater number of Spaniards among the UDVP (p < 0.01) and among those with tattoos (p < 0.001). The first manifestation of the disease in 53% of the cases was extrapulmonary Tuberculosis. CONCLUSIONS: Prisons are key places in the prevention and monitoring of HIV infection. The use of care programmes, including maintenance programmes using Methadone, for drug-dependent patients are recommended. The continuation of programmes tracking Tuberculosis, the main illness related to HIV infection in prison, is also recommended.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Biomechanical effects of different surgical procedures on the extensor mechanism of the patellofemoral joint.

Loadbearing stresses in the patellofemoral joint were studied at different degrees of flexion before and after various surgical techniques recommended to treat knee disorders. Surgical procedures intended to reduce the intensity of stress were analyzed experimentally. The study was done using different experimental methods on whole knee specimens from fresh human cadavers that were not treated with formaldehyde. The results indicate that the most predictable procedure for increasing surface area and decreasing patellar stress is a combined procedure of anterior displacement of the anterior tibial tubercle by 1 cm while displacing it 0.5 to 1 cm medially.

Biomechanical Phenomena↗
PubMed1992

[Colonic transit time (segmental and total) in healthy subjects and patients with chronic idiopathic constipation].

BACKGROUND: The efficacy of the treatment of patients with chronic idiopathic constipation not responding to normal therapeutic measures depends on correct functional diagnosis. The study of the segmentary and total colonic transit time with radioopaque markers is the most economic technique in everyday clinic ambience for functionally evaluating these patients. METHODS: Segmental and total colonic transit time was calculated with the use of radioopaque markers in 23 healthy subjects (12 men and 11 women) and in 13 women with severe idiopathic constipation. Twenty markers were administered daily for three consecutive days and simple x-rays of the abdomen were made on the fourth, seventh and in some cases on the tenth day. In addition, the symptomatology of 9 patients was collected by means of a 30 day diary. RESULTS: The maximum values of transit time (mean + 2SD) obtained in the healthy subjects were 17, 25, 26, and 49 hours for the right colon, left colon, rectosigmoid and the whole colon, respectively. The time of left colon transit was significantly lower in the women. The transit time in constipated patients permitted the differentiation of three functional patients: a) slowing of the right and left colon possibly associated to rectosigmoid slowing in 5 patients; b) isolated slowing in the left colon in 4 patients and c) isolated rectosigmoid slowing in 4 patients. Group a) was characterized by long total colonic transit times while these were normal in 2 patients of group b) and in one patient of group c). No differences were seen in the symptomatology of the groups. CONCLUSIONS: The calculation of segmentary and total colonic transit time with radioopaque markers is a simple technique which permits the detection of different subgroups of patients with chronic idiopathic constipation refractory to normal treatment. The exact typification of the functional anomaly is an important basis for the individualization of treatment.

Adult↗
PubMed1992

[The efficacy of Plantago ovata as a regulator of intestinal transit. A double-blind study compared to placebo].

The effect of Plantago ovata on patients with chronic constipation (CC) with or without irritable bowel syndrome (IBS) has been assessed by a double blind study comprising 20 patients with CC of which 10 had associated IBS. A clinical questionnaire, weight of feces and intestinal transit time measured with radiopaque markers were done. Patients were then randomly distributed, 10 receiving PO and 10 placebo. Similar tests were done after treatment one month later. All patients receiving PO had good results against only one in the placebo group. Frequency of stools increased from 2.5 +/- 1 vs 8 +/- 2.2 stools per week, p less than 0.001 for paired data). A decrease in consistency of stools was also observed in the treated group. Fecal weight and colonic transit time were not significantly modified in placebo patients, while weight increase was observed in the treated ones (124 +/- 71 vs 194 +/- 65, gr/d p less than 0.001 for paired data) as well as a decrease in transit time (48 +/- 15 vs 34 +/- 18 hours p less than 0.05 for paired data). No adverse effects were observed and particularly no flatulence as often seen in patients on bran.

Adult↗
PubMed1991

Chronic idiopathic constipation: the importance of transit time studies.

Chronic idiopathic constipation includes a very heterogeneous group of alterations which cannot be correctly defined only by their clinical appearance and require an examination of the colonic transit time. This test is performed by using a specific number of radiopaque markers and a fixed number of X-ray observations. By means of transit time study, we can classify the constipated patients into 4 groups: a) patients with stasis in the right colon (17-53% of cases) which implies an alteration of propulsive forces or absence of mass movements and segmentary motor activity; b) stasis in the left colon (13-27% of cases) which could be due to a "reflux" of colonic contents or to a hyperactive sigmoid; c) rectosigmoid stasis (20-33% of cases) which is secondary to a megarectum. Internal anal sphincter (IAS) and/or external anal sphincter (EAS) function failure and d) normal transit time (greater than 40 of cases) which is commonly due to psychological problems or to a low-fiber-content diet. We can conclude that transit time study is not necessary in mild constipation, but it is advised for those patients who do not respond to standard medical therapy or when surgery is being contemplated.

Anal Canal↗
PubMed1991

Colonic sensitive-motor alterations in the irritable bowel syndrome.

The pathogenetic factors involved in the genesis of the irritable bowel syndrome (IBS) has not been fully explained yet. The abnormalities observed in these patients are a hypersensitivity to distension and an amplification of painful sensations. The motor activity of sigmoid colon shows an increased motility index in IBS patients with constipation and a low motility index in those with diarrhea. An hypercaloric meal induces a hypermotility in these patients. In our experience rectal distension evokes abdominal pain in 78% of cases at volumes of 100ml (less than than controls and constipated patients). The perfusion of rectum induces continuous abdominal pain in 89% of IBS patients. We can say that the motility of the whole colon over prolonged periods of time may represent an important progress in understanding the motor function in these patients.

Abdominal Pain↗
PubMed1991

[Recurrent benign intrahepatic cholestasis. A case report].

A case of benign and recurrent intrahepatic cholestasis in a 46 year old female is presented. This patient, who correctly coincided with the diagnosis criteria, had 2 episodes of jaundice and pruritus over a period of 4 years. The diagnosis criteria, clinical features, blood tests, etiopathogenesis and treatment are reviewed.

Cholestasis, Intrahepatic↗
PubMed1989

A new physiologic correction technique for re-establishment of pulmonary circulation. Experimental surgical development.

A new physiologic technique is presented for surgical correction of truncus arteriosus, pseudotruncus, transposition of the great arteries, double right ventricular outflow tract with subpulmonary ventricular septal defect and certain cases of Fallot's tetralogy. The basis of the technique are creation of a neo-right atrium, neo-pulmonary trunk, neo-right atrioventricular valve and a neo-pulmonary valve by right angular atriotomy and insertion of a homologous pericardial patch with a monocuspid valve. The pulmonary circulation is re-established by anastomosis of the neo-pulmonary trunk to the pulmonary tree. The technique was used on 26 mongrel dogs. In 14 the experiments were preliminary, to evaluate the technique's validity, and in the other 12 it was performed with extracorporeal circulation and the hemodynamic status was studied at 30 and 180 min postoperatively. The technique and its results and potential advantages are described. Clinical application is considered to be feasible.

Anastomosis, Surgical↗