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Biomedical subjects

J C Ruiz

Publications and source records attributed to J C Ruiz.

At least 91 records · Page 5Linked to original sources
PubMed1996

Menopause, fat and lean distribution in obese women.

OBJECTIVES: Whether menopause per se influences fat distribution independently of the effect of aging remains controversial. The lack of consistency in the menopause related changes in body fat distribution may be the result of differences in the methods for measuring fat distribution or in the characteristics of the women studied. The aim of this cross sectional study in obese women was to compare total body composition and regional fat and lean distribution, in premenopausal, perimenopausal and postmenopausal women. METHODS: Body composition was assessed by dual energy X-ray absorptiometry (DEXA) in premenopausal (n = 26), perimenopausal (n = 24) and postmenopausal (n = 73) obese women with no intercurrent diseases. RESULTS: It was shown that postmenopausal obese (n = 73) women had a higher proportion of total fat mass in the trunk and a lower proportion of total fat and lean mass in the femoral and leg regions than premenopausal women after adjustment for age and total fat mass. In the same analysis, perimenopausal women had a lower proportion of total fat in the leg and femoral regions and of total lean in the femoral region than premenopausal women; they had a regional body composition similar to that of postmenopausal women. CONCLUSION: The present data indicate that in obese women, post menopause and perimenopause are associated with differences in fat and lean distribution, independently of age and total fat.

Absorptiometry, Photon↗
PubMed1996

Embryonic expression of eph signalling factors in Xenopus.

Cellular communication in the developing embryo is mediated by receptor-ligand interactions at the cell surface. Receptor protein tyrosine kinases (RTKs) have been shown to play a critical role in the development of the vertebrate embryo. The eph receptors are a large subclass of RTKs for which a corresponding ligand family has only recently been described. The restricted expression patterns of several eph receptors imply roles for these molecules in early vertebrate development. We have isolated both a ligand of the eph ligand family (ELF), that we have named XELF-a, and an eph-related receptor, XE10, the likely homolog of the murine eck/Sek-2 receptor. At least two forms of the XELF-a transcript are present in the developing embryo. A truncated form of the XELF-a ligand, XELF-á, is the first ELF ligand isolated that lacks both the membrane-spanning and membrane-anchoring motifs conserved among this family, suggesting that ELF ligands can function as fully soluble molecules in vivo. XELF-a and XE10 are expressed maternally and throughout early embryogenesis, while XELF-á is only expressed zygotically. The dynamic expression patterns of these signalling molecules, in both mesoderm and neurectoderm, suggest that they may play a role in the patterning of the early vertebrate embryo.

Amino Acid Sequence↗
PubMed1996

Spontaneous hepatocellular carcinoma in Saimiri boliviensis.

Hepatocellular carcinomas are rare in nonhuman primates. In this study we found the first naturally occurring hepatocellular carcinoma in a Squirrel Monkey (Saimiri boliviensis) of at least 24 years of age. In the necropsy, the liver was cirrhotic and contained multiple tumorous nodules, which varied in diameter from 3 to 15 mm. The lungs also contained small neoplastic masses. In the histological study, samples of liver, lungs, and other organs were taken and fixed in 10% buffered formalin, embedded in paraffin, cut at 5 microns, and colored with hematoxylin and eosin. The histological study of the liver permitted the detection of multiple masses of neoplastic liver cells in a closely packed trabecular configuration surrounded by a well-developed capillary basement membrane. Cirrhotic changes also were observed in the liver. The histological study of the lung confirmed the metastasis of the hepatocellular carcinoma. Metastasis was not found in other organs.

Animals↗
PubMed1995

Circulating adhesion molecules during kidney allograft rejection.

Adhesion molecules appear on leukocytes and endothelial cells mediating the localization and migration of leukocytes to sites of inflammation. Rejecting kidney grafts have shown an increased expression of these molecules. Recent reports have detected in serum soluble forms of adhesion molecules that could play a role in regulating inflammation. We have measured by ELISA the circulating serum levels of ICAM-1, VCAM-1 and E-selectin in: 23 controls, 33 chronic renal failure patients (CRF), 20 hemodialysis patients (HD), 17 samples from 6 patients with stable kidney graft function (STx), 25 samples from 8 patients with steroid-responsive rejection proven by biopsy, and 28 samples from 9 patients with steroid-resistant rejection and good response to OKT3. There was not a rise in cICAM-1 or cE-selectin levels during rejection compared with the steady phase before and after rejection. In the case of cVCAM-1, only the OKT3 group showed increased rejection levels (P < 0.05) that were maintained after rejection. For ICAM-1, CRF and HD groups had higher levels than the remaining groups. cVCAM-1 levels were elevated in all groups when compared with control, furthermore, OKT3 and HD groups had higher levels than the STx, CRF, or steroid-responsive groups. For cE-selectin, we only found differences between the CRF and both rejection groups. Serum creatinine correlated significantly with c-ICAM-1 and cVCAM-1 R = 0.30 and R = 0.22), but not with cE-selectin. We conclude that soluble adhesion molecules levels are not valuable markers for rejection. Patients with chronic renal failure have increased levels of adhesion molecules, which could reflect an impaired elimination.

Antibodies, Monoclonal↗
PubMed1995

Influence of spontaneous calcium intake and physical exercise on the vertebral and femoral bone mineral density of children and adolescents.

Peak bone mass is determined mainly by genetic-ethnic factors, but environmental factors such as calcium intake and physical activity during childhood and adolescence could play a role. We have measured the bone mineral density (BMD) of 151 healthy children and adolescents, ages 7-15.3 years. Density was measured by dual X-ray absorptiometry (DXA) at two sites (lumbar verterbrae L1-L4 and the upper femur), and the data were analyzed in terms of the height, weight, sexual maturation, spontaneous calcium intake, and physical activity. Of the children, 57-71% had calcium intakes below 1000 mg/day. BMD increased with pubertal maturation from 0.68 +/- 0.08 to 0.92 +/- 0.09 g/cm2 (vertebral bone density, VBD) and from 0.87 +/- 0.10 to 1.03 +/- 0.09 g/cm2 (femoral bone density, FBD) between Tanner stage 1 and 5. Multiple regression analysis showed that body weight and Tanner stage were main determinants of bone density when expressed as g/cm2. The weekly duration of sports activity also influenced both the vertebral (p < 0.001) and femoral (p = 0.01) sites, especially in girls and during puberty. Dietary calcium appeared to be another independent determinant of BMD, especially before puberty, at the vertebral (p = 0.02) site. Most important, dietary calcium was found to be the main determinant of vertebral mineral density, when expressed as z score, in both sexes. Moreover, 93% of the 28 children with low vertebral z score values (below -1) and 84% of the 31 children with low femoral z score values (below -1) had dietary calcium intakes below 1000 mg/day.

Absorptiometry, Photon↗
PubMed1995

Interleukin-10 and the monocyte/macrophage-induced inflammatory response in septic shock.

Interleukin (IL)-10 is a potent immunosuppressant of monocyte/macrophage function and may help control the inflammatory response induced by bacterial infection. To analyze whether IL-10 is detectable in plasma of patients with septic shock and to evaluate its relationship with endotoxin (lipopolysaccharide [LPS])-induced and monocyte/macrophage-induced inflammatory response, plasma IL-10, tumor necrosis factor (TNF)-alpha, IL-1 beta, IL-6, IL-8, LPS, and neopterin were studied in 24 patients with septic shock and in 12 critically ill patients. Eighty-three percent of patients with septic shock and 25% of critically ill patients had detectable levels of IL-10 (P < .001). There was a significant correlation between plasma IL-10, neopterin (r = .72), TNF-alpha (r = .76), IL-6 (r = .68), and IL-8 (r = .61) levels in patients with septic shock. Monocyte/macrophage activation leads to massive secretion of IL-10, which, however, seems to be unable to control the increased production of proinflammatory mediators during septic shock.

APACHE↗
PubMed1995

Mutations in L1-CAM in two families with X linked complicated spastic paraplegia, MASA syndrome, and HSAS.

The suggestion that the three X linked syndromes X linked spastic paraplegia (MIM 312900), MASA syndrome (MIM 303350), and X linked hydrocephalus owing to stenosis of the aqueduct of Sylvius (MIM 307000) are variable clinical manifestations of mutations at the same locus at Xq28 was confirmed by the finding of mutations in the L1-CAM gene in the three syndromes. Recently, two families in which different subjects showed a clearly different phenotype within the same family of the three X linked syndromes were described. A reverse transcription PCR assay was developed for the analysis of the L1-CAM cDNA in two of the members of these families. RNA isolated from EBV transformed cell lines and a colon carcinoma derived cell line was used as a starting material. The L1-CAM cDNA of two male patients from each family was sequenced. We report two new mutations in the L1-CAM gene in these two families showing that the three different phenotypes observed in different generations within the same family are variable phenotypic expressions of the same mutation.

Base Sequence↗
PubMed1994

Identification of novel protein kinases expressed in the myocardium of the developing mouse heart.

In Drosophila and Caenorhabditis, signal transduction pathways initiated by the activation of receptor-protein tyrosine kinases can mediate developmental fate decisions. In order to examine whether similar mechanisms are employed during mammalian embryogenesis, we undertook a search for novel protein kinases expressed during heart development in the mouse. The primitive mouse heart is formed between 7.75 and 8.5 days post coitum (dpc) and consists of myocardial and endocardial cells. A reverse transcriptase polymerase chain reaction-based approach was used to amplify protein kinase specific products from cDNAs obtained from 8.5 dpc heart tissue. Twenty independent PCR products corresponding to either protein serine/threonine or tyrosine kinases were identified. In this report, we describe the characterization of two of the genes corresponding to the novel PCR products (designated Hek2 and msk). Hek2 encodes the mouse ortholog of human HEK2, a recently identified member of the eph receptor-protein tyrosine kinase gene family. Prior to and at the time of heart formation (7.5-8.0 dpc), Hek2 is expressed in the cranial (rostral) region of the embryo from which a subpopulation of cells will give rise to the rudimentary heart. Between 8.0 and 9.5 dpc, Hek2 mRNA expression is observed in myocardial cells, head mesenchyme and paraxial mesoderm. Hek2 transcripts are not detected in endocardial cells. After 9.5 dpc, Hek2 expression is downregulated. msk (for myocardial SNF1-like kinase) encodes a putative protein serine/threonine kinase most similar to the yeast gene SNF1. msk mRNA expression is restricted to myocardial cells and their progenitors in the 7.75-8.5 dpc developing heart. Subsequently, msk mRNA expression is rapidly downregulated. The patterns of Hek2 and msk expression suggest that these protein kinases may function during development of the primitive heart.

Amino Acid Sequence↗
PubMed1994

The expression of the receptor-protein tyrosine kinase gene, eck, is highly restricted during early mouse development.

Cell-cell interactions during embryogenesis have been shown to be important for establishing developmental fates in a number of organisms such as Drosophila and Caenorhabditis. One class of genes shown to mediate this process are receptor-protein tyrosine kinases (R-PTKs). To examine whether R-PTKs might participate in similar mechanisms operating in the mammalian embryo, an important prerequisite is to show that these genes are expressed in spatial and temporal patterns consistent with such a role. Here, we analyze the expression of eck, a member of the eph family of R-PTKs, during gastrulation and early organogenesis by in situ hybridization. eck transcripts are first detected in gastrulation stage embryos (6.5-7.5 days post coitum (dpc)) in ectodermal cells adjacent to the distal region of the primitive streak. By the neural plate stage (approximately 7.5 dpc), eck expression becomes restricted to the extreme distal end or node of the primitive streak. After the beginning of somitogenesis (approximately 8.0 dpc), eck expression persists in the node as this structure regresses toward the caudal end of the embryo. In addition, beginning at the mid head fold stage (approximately 7.75 dpc), we observe that eck exhibits a dynamic and spatially restricted expression pattern in the prospective hindbrain region. eck transcripts are initially detected in a 5-cell wide strip of mesodermal cells underlying prospective rhombomere 4 (r4). Subsequently at the beginning of somitogenesis, eck mRNA expression is observed in prospective r4. At the 4--8-somite stage, eck transcripts are observed in r4, mesenchymal cells underlying r4, and surface ectoderm in the vicinity of the developing second branchial arch. By the 10-somite stage, eck mRNA expression in these cells is downregulated. Additionally, at the 5--8-somite stage, eck transcripts are detected initially in the lateral mesenchyme immediately underlying the surface ectoderm adjacent to r5 and r6, and subsequently in surface ectoderm overlying the developing third branchial arch. These data suggest that eck may be involved in cell-cell interactions guiding early hindbrain development.

Amino Acid Sequence↗
PubMed1994

Exclusion of linkage to 14q23-24 in a family with Holt-Oram syndrome.

Holt-Oram syndrome is an autosomal dominant disorder with congenital heart defects and skeletal malformations of the upper extremities. A patient with a deletion of 14q23-24 and Holt-Oram syndrome has been described. In this report, however, genetic linkage to the 14q23-24 region is excluded in a multigeneration family with five available individuals affected with Holt-Oram syndrome. Familial Holt-Oram syndrome might be different from the syndrome with the 14q23-24 deletion.

Abnormalities, Multiple↗
PubMed1994

Aortic aneurysm in a Cebus apella monkey with experimentally induced atherosclerosis.

The sudden death of a Cebus apella female (> 19 years old) on an experimental hyperlipidic diet during three years is described. The gross lesions were hemothorax, atherosclerotic plaques in the aortic curve, and an aneurysm in the ascending aorta. Histologically, an enlargement of the intima in the ascending aorta with hyalinization and a thrombus were observed. The media was thinned and showed sclerosis and hemorrhage extending to the tunica adventicia.

Animals↗
PubMed1994

Dialysis membranes and PTH changes during hemodialysis in patients with secondary hyperparathyroidism.

Changes in parathyroid hormone (PTH) during hemodialysis have been explained by the influence of ionized calcium changes on PTH secretion. In this study we have investigated the influence of dialysis membranes of different permeability on PTH changes during hemodialysis. Five chronic renal failure patients underwent three consecutive hemodialysis sessions with cuprophane (CUP) polysulfone (PS) and polyacrylonitrile (PAN). Two hours of isolated ultrafiltration were followed by 3 h dialysis. A significant decrease in carboxy terminal PTH (COOH PTH) was observed with PAN (p < 0.05) but not with CUP or PS. Intact PTH decreased (p < 0.001) with all three membranes, following a significant increase in ionized calcium (p < 0.001). Sieving coefficients for COOH PTH were significantly lower with CUP than with PS (p < 0.05) or PAN (p < 0.001). Intact PTH sieving coefficients were near zero for all three membranes. COOH PTH and intact PTH clearance rates were significantly higher with PAN (p < 0.001) than with PS or CUP, either in isolated ultrafiltration or with dialysis fluid. Thus PTH changes during hemodialysis do not only depend on the increase in calcium but also on the nature of the dialysis membrane. Adsorption of PTH to the PAN membrane surface explain the high PTH clearance rates achieved with this filter.

Acrylic Resins↗
PubMed1993

Case report 807: Infantile desmoid-type fibromatosis.

A case of infantile desmoid-type fibromatosis has been described and discussed. The clinical and pathological features were described, and the interrelationship of this entity with others, together with the wide range of benign structures, was discussed. Other cases resembling this one have been described.

Fibroma↗
PubMed1993

Glioblastoma multiforme of donor origin after renal transplantation: report of a case.

A case of transmission of a glioblastoma multiforme from the donor to a kidney transplant recipient in the absence of previous ventriculosystemic shunt is described. The recipient was a 48-year-old woman who developed a fever with no other associated symptoms 17 months posttransplant. Physical examination revealed a large nonpulsatile mass on the upper graft pole. Histopathologic examination showed a highly cellular neoplasm with fusiform and globoid cells, a high grade of nuclear pleomorphism and mitosis, necrosis with pseudopalisading, and vascular proliferation. Immunohistochemistry of the cells showed them to contain glial fibrillary acidic and S-100 proteins, consistent with a glioblastoma multiforme. We conclude that the risk of tumor transmission from donors with primary central nervous system tumors to kidney transplant recipients, is real and should be considered when evaluating a graft mass in such patients.

Adult↗