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Biomedical subjects

S Serrano

Publications and source records attributed to S Serrano.

At least 19 recordsLinked to original sources

In vitro synthesis of type I collagen: quantification of carboxyterminal propeptide of procollagen type I versus tritiated proline incorporation.

Radioimmunoassay of the carboxyterminal propeptide of human type I procollagen has been recently introduced to measure in vitro synthesis of type I collagen by osteoblasts and fibroblasts. However, it has not been assessed whether the equivalent results are obtained with this new assay and with tritiated proline incorporation to collagen protein. To this purpose, both methods were used to quantify synthesis of type I collagen in normal human osteoblast cultures to which fetal calf serum and human serum were added in order to stimulate protein synthesis. A positive correlation in the results obtained by both methods was obtained (r = 0.95, P = 0.0001). Given the technical advantages of detection of levels to carboxyterminal propeptide of type I procollagen, we consider that this is the technique of choice for the quantification of in vitro synthesis of type I collagen by normal human osteoblasts.

Aged

Subcellular adaptation of the human diaphragm in chronic obstructive pulmonary disease.

Pulmonary hyperinflation impairs the function of the diaphragm in patients with chronic obstructive pulmonary disease (COPD). However, it has been recently demonstrated that the muscle can counterbalance this deleterious effect, remodelling its structure (i.e. changing the proportion of different types of fibres). The aim of this study was to investigate whether the functional impairment present in COPD patients can be associated with structural subcellular changes of the diaphragm. Twenty individuals (60+/-9 yrs, 11 COPD patients and 9 subjects with normal spirometry) undergoing thoracotomy were included. Nutritional status and respiratory function were evaluated prior to surgery. Then, small samples of the costal diaphragm were obtained and processed for electron microscopy analysis. COPD patients showed a mean forced expiratory volume in one second (FEV1) of 60+/-9% predicted, a higher concentration of mitochondria (n(mit)) in their diaphragm than controls (0.62+/-0.16 versus 0.46+/-0.16 mitochondrial transections (mt) x microm(-2), p<0.05). On the other hand, subjects with air trapping (residual volume (RV)/total lung capacity (TLC) >37%) disclosed not only a higher n(mit) (0.63+/-0.17 versus 0.43+/-0.07 mt x microm(-2), p<0.05) but shorter sarcomeres (L(sar)) than subjects without this functional abnormality (2.08+/-0.16 to 2.27+/-0.15 microm, p<0.05). Glycogen stores were similar in COPD and controls. The severity of airways obstruction (i.e. FEV1) was associated with n(mit) (r=-0.555, p=0.01), while the amount of air trapping (i.e. RV/TLC) was found to correlate with both n(mit) (r=0.631, p=0.005) and L(sar) (r=-0.526, p<0.05). Finally, maximal inspiratory pressure (PI,max) inversely correlated with n(mit) (r=-0.547, p=0.01). In conclusion, impairment in lung function occurring in patients with chronic obstructive pulmonary disease is associated with subcellular changes in their diaphragm, namely a shortening in the length of sarcomeres and an increase in the concentration of mitochondria. These changes form a part of muscle remodelling, probably contributing to a better functional muscle behaviour.

Adaptation, Physiological

[Screening for bone disease risk with clinical factors in women after physiologic menopause].

BACKGROUND: Densitometric screening for osteoporosis in postmenopausal women has not been demonstrated cost-effective. We have tried to identify clinical factors for screening previous to densitometry avoiding unnecessary explorations. PATIENTS AND METHODS SETTING: outpatient clinics of a menopausal unit in a 450-bed general hospital. Cross-sectional study, in two steps, of two groups of 140 and 284 women attending for physiological menopause. A clinical questionnaire, physical data and lumbar densitometry (Hologic QDR 1000) were obtained classifying the cases as "normal" or "low bone mass" (osteopenia or osteoporosis) according with the WHO criteria. In the first group a logistic regression analysis was done to identify predictive factors for abnormal densitometry, then validated in the second group. Sensitivity, specificity, predictive values (PV) and classification ability of clinical factors were analyzed. RESULTS: Four factors were independent predictors of abnormal densitometry: age > 51 (odds ratio [OR] = 6.64; 95% CI, 2.36-18.7); body weight < 70 kg (OR = 4.32; 95% CI, 1.71-10.09); years of fertility < 32 (OR = 3.77; 95% CI, 1.36-10.04), and number of live births > 2 (OR = 3.47; 95% CI, 1.27-9.53). Presence of one factor offers: sensitivity 91.9%; specificity 15%; positive PV 66.6%, and negative PV 50%, whereas the presence of two factors offers: sensitivity 62.7%; specificity 70%; positive PV 79.9%, and negative PV 50.3%. Clinical screening allows, when two factors are present, to avoid a 35.5% of densitometries and the false-negative cases represent 18%. CONCLUSIONS: Detection of bone-risk clinical factors (abnormal densitometry) yields a screening, previous to densitometry, that avoids at least one third of explorations in women with physiological menopause, improving the efficiency of the test.

Cross-Sectional Studies

[Estimate of bibliometric indicators of the impact of +Archivos de Bronconeumología].

The main bibliographic impact factors of ARCHIVOS DE BRONCONEUMOLOGIA for the past two years are estimated. Citations of ARCHIVOS DE BRONCONEUMOLOGIA in 1996 and 1997 by Medicina Clínica and all citing journals grouped under the heading "Respiratory System" in the Science Citation Index were counted. The year the citation appeared and the year of publication of the article in ARCHIVOS DE BRONCONEUMOLOGIA were recorded. The total number of articles published by ARCHIVOS DE BRONCONEUMOLOGIA between 1994 and 1996 were also counted. Based on these data we calculated our journal's impact factor for each year studied. Relative impact factor was also figured. In 1996 the exposure factor achieved was 1.602, the half-life of articles was 2.00 years, the impact factor was 0.069 and the relative impact factor was 1.371. In 1997 the exposure index was 1.477, the citation half-life was 3.00 years and the impact factor was 0.030. In conclusion, the international impact of ARCHIVOS DE BRONCONEUMOLOGIA is modest, although our relative impact factor is greater than that of some other internal medicine publications or specialized journals listed in Journal Citation Reports.

Bibliometrics

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

Vitamin D treatment in myelodysplastic syndromes.

Myelodysplastic syndromes (MDS) are a group of clonal disturbances with defective cellular differentiation. Vitamin D3 (VD) analogues can act on the differentiation and maturity of different cell lines. We studied the effects of VD on a series of patients with MDS in an open-design trial. Nineteen patients, 12 men and seven women, with MDS were included. Patients were 74.8 +/- 5.6 years (mean +/- SD), seven had refractory anaemia with ringed sideroblasts, five had refractory anaemia, one had refractory anaemia with excess of blasts and six had chronic myelomonocytic leukaemia. All the patients were in a low to intermediate risk group. Mean follow-up period was 26.21 months, range 9-75. Responders were defined as follows: granulocyte or platelet count increase by 50%, or haemoglobin increase of 1.5 g/dl or transfusion needs decrease by 50%. The first five patients received 266 microg of calcifediol three times a week and the other 14 received calcitriol (0.25-0.75 microg/d). Response was observed in 11 patients. In the calcifediol-treated group, one case responded, three were nonresponders, and one showed progression. In the calcitriol group, 10 were responders (two with major response), and four were non-responders. No correlation was observed between baseline levels of vitamin D metabolites and the presence of response. No hypercalcaemia was observed. Treatment with vitamin D3 metabolites could induce a long-standing response of the haematological disturbance in some low-intermediate risk MDS patients without inducing hypercalcaemia.

Aged

Immunoreactive osteocalcin forms in conditioned media from human osteoblast culture and in sera from healthy adult control subjects and patients with bone pathologies.

BACKGROUND: The aim of this work was to study the immunoreactive forms of bone Gla protein (BGP) present in conditioned media of human osteoblast cultures (BGP released from osteoblast) and in the sera of healthy adult control subjects and patients with bone pathologies (chronic renal failure on haemodialysis, Paget's disease of bone and post-menopausal osteoporosis). METHODS: The technical procedure used was a combination of high-performance liquid chromatography (HPLC) and different BGP assays with several specificities to analyse BGP levels in the different HPLC fractions. Aliquots of conditioned media or sera were purified through a Sephadex G-50m column and by HPLC (C4 reverse-phase column) in a 25-40% acetonitrile gradient. Two-minute fractions were collected and divided into three aliquots in order to determine osteocalcin content using three different assays: (a) ELSA-OST-NAT IRMA, which only detects intact osteocalcin; (b) ELSA-OSTEO IRMA, which detects intact osteocalcin and N-terminal fragments; and (c) OSCA Test RIA, which detects intact osteocalcin, C-terminal and other fragments. RESULTS: We found different immunoreactive forms of osteocalcin in the culture medium of human osteoblasts and in sera from control subjects and patients for the bone pathologies studied. We did not find great qualitative differences between the immunoreactive osteocalcin profile found in the culture medium from human osteoblasts and the sera from healthy control subjects. However, the different bone pathologies show different characteristic patterns of immunoreactive forms of osteocalcin. CONCLUSIONS: An interesting finding has been the detection, both in sera and in osteoblast culture media, of several immunoreactive forms of intact osteocalcin that eluted from HPLC at different acetonitrile percentages, and therefore correspond to different molecular forms.

Adult

Optimization of the tyrosinase mRNA probe to detect circulating melanocytes with reverse transcription and polymerase chain reaction.

It was recently suggested that reverse transcription polymerase chain reaction (RT-PCR)-based detection of tyrosinase messenger RNA (mRNA) in peripheral blood is useful in the early detection of circulating tumor cells, since tyrosinase is thought to be a melanocyte-specific marker. However, the sensitivity of detection of these cells in circulation is controversial, some authors reporting 0% effectiveness, others obtaining 100% efficacy. We developed a modification of a technique to process blood samples to detect tyrosinase mRNA, and tested the method with 50 samples from as many patients with histologically confirmed malignant melanoma in different stages. Whole blood was processed by discarding the plasma and extracting RNA from density gradient-isolated peripheral blood lymphocytes. The RNA samples were tested with a sensitive nested primer RT-PCR assay. Sensitivity was tested using RNA extracted from SK-mel-1 human melanoma cells diluted serially with peripheral blood obtained from healthy control subjects. A lymph node from a patient with confirmed disseminated melanoma served as the positive control. Our technique was able to detect tyrosinase mRNA in samples from the 37 patients with progressive metastatic melanoma. The test detected tyrosinase mRNA from both the melanoma cell line and the positive lymph node. Our method to extract RNA from whole blood improves the specificity and sensitivity of tyrosinase mRNA detection by RT-PCR. The test should be of use in determining the prognosis of patients with melanoma, and in deciding when to initiate early treatment in patients with malignant melanoma.

Humans

Melanocytic nevi and risk of cutaneous malignant melanoma in southern Spain.

The main objective of this study was to assess whether cutaneous malignant melanoma (CMM) shows a stronger relation with the melanocytic nevi count at the site where CMM was diagnosed than with the melanocytic nevi count at other sites, stratifying by histologic CMM type, in a southern Mediterranean population. Cases and controls were selected from a population in southern Spain in 1988-1993. The study population included 116 incident cases with non-familial CMM (International Classification of Diseases 9th Revision (ICD-9) code 172), and 116 controls matched 1:1 for sex and age (+/- 4 years). Data were collected by personal interview, and melanocytic nevi were counted over the entire body surface by clinical skin examination performed by a dermatologist. Crude and multiple risk factor-adjusted odds ratios and 95% confidence intervals were computed by conditional logistic regression analysis. After adjustment by skin type, unexposed skin color, and sun exposure, CMM was found to occur significantly more frequently in individuals with a high number of melanocytic nevi at the same site where CMM originated (odds ratio (OR) for >8 nevi = 12.0, 95% confidence interval (CI) 1.3-108.2). The ability to predict the number of melanocytic nevi on different anatomic sites on CMM, but excluding the CMM cases on each corresponding site, was also examined. A significant trend with the number of nevi on the anterior surface of thighs was found (OR for >4 nevi = 4.5, 95% CI 1.4-14.9). Melanocytic nevi count on the melanoma site was the variable most closely related to superficial spreading melanoma subtype (SSM) (OR for >8 nevi = 82.19, 95% CI 2.72-2,454). On the other hand, the number of melanocytic nevi on the melanoma site was unrelated to risk of CMM subtypes other than SSM. These results support the hypothesis that nevi are an important risk factor for melanoma, especially SSM, in populations with a darker ethnic background.

Case-Control Studies

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

Acute effects of ethanol on mineral metabolism and trabecular bone in Sprague-Dawley rats.

In order to assess the effects of acute ethanol intoxication on bone, 45 female Sprague-Dawley rats were studied. Five rats were sacrificed at baseline. The remainder received either ethanol (2 g/kg of body weight) intraperitoneally or isotonic saline. Rats were sacrificed in groups of 10 (5 intoxicated and 5 placebo) at 1, 4, 8, and 24 hours after injection. At the time of sacrifice, a blood sample was obtained and the 4th vertebra was excised for histomorphometric analysis of undecalcified bone. Effect of ethanol was assessed by an analysis of variance test using a Scheffé procedure. In ethanol-treated rats we observed (mean +/- SD, ethanol versus controls, maximum difference point, P value) a significant decrease in osteiod surface with osteoblasts (42.86 +/- 15.61% versus 64.57 +/- 6.24%, P < 0.05); osteoclast number (0.05 +/- 0.02 n/mm2 versus 0.17 +/- 0.09 n/nm2, P < 0.05), and osteocalcin (36.9 +/- 2.21 ng/ml versus 45.8 +/- 5.1 ng/ml, P < 0.05). Osteoclast surface was initially reduced (0.129 +/- 0.09% versus 0.425 +/- 0. 26%, P < 0.01) but showed a subsequent increase (0.765 +/- 0.24% versus 0.226 +/- 0.17%, P < 0.01) attributable to alcohol. There was also a significant decrease in serum Ca (8.51 +/- 0.23 mg/dl versus 9.10 +/- 0.29 mg/dl, P < 0.01) and parathyroid hormone values (23.51 +/- 5.72 pg/ml versus 76.39 +/- 11.66 pg/ml, P < 0.001). We conclude that acute alcohol intoxication in rats induces early striking changes in bone histology and analytical parameters, not completely reversed after 24 hours. These data are consistent with a toxic effect induced by alcohol on bone.

Acid Phosphatase

Thymoma associated with CD4+ lymphopenia, cytomegalovirus infection, and Kaposi's sarcoma.

A case of thymoma with associated opportunistic infections, CD4/CD8 T-lymphocyte imbalance, low CD4-positive T-lymphocyte counts and Kaposi's sarcoma (KS) without HIV infection is reported. Cytomegalovirus inclusions were identified in the nuclei of some KS spindle and endothelial cells. It is known that KS has a high prevalence in AIDS patients and has occasionally been associated with other causes of immunosuppression. In previous studies, coexisting KS and thymoma were related to myasthenia gravis, corticosteroid treatment and excess CD8-positive T-lymphocyte counts. More recently an imbalance between CD4 and CD8 positive T lymphocytes has been identified in association with thymoma. The present case suggests that there may be a relationship between thymoma, CD4-positive lymphopenia, and KS.

Aged

[New prospects in cystic fibrosis treatment].

Only a few years ago, cystic fibrosis (CF) was considered the most frequent genetic disease in childhood, although survival has increased considerably in recent years owing to improved treatment. We discuss treatments that are still relevant as well as others that are under investigation now, aiming for better understanding of the disease and the therapies that have improved quality of life for CF patients.

Cystic Fibrosis