Biomedical subjects

E Crespo

Publications and source records attributed to E Crespo.

At least 19 recordsLinked to original sources

PubMed2004

[Morphometric study with imaging techniques of Trolard's vein and its anastomosis to the superior longitudinal sinus].

OBJECTIVE: The main objective of this work is to allow the anatomical localization of the vein of Trolard (VT) or great anastomotic vein, before neurosurgical approaches to the parietal region. MATERIAL AND METHODS: Thirty four patients were subjected to cerebral angiography. Measurements of different points related to the anatomy of the vein were taken in 41 studies on the lateral projection. A statistical analysis was performed. CONCLUSIONS: The measures obtained are of practical utility to locate the final portion of the vein of Trolard in its anastomotis to the sagittal superior sinus (SLS) for planning neurosurgical approaches to the parietal region.

Adult↗

PubMed2002

Influence of boron supplementation on vertebral and femoral bone mass in rats on strenuous treadmill exercise. A morphometric, densitometric, and histomorphometric study.

We studied the effect of boron supplement on experimental osteopenia caused by strenuous exercise in 93- d-old female Wistar rats. A control group of 15 rats was not manipulated. The exercise group of 30 rats was divided into 2 groups of 15 rats each, one that was fed a diet supplemented with 50 mg/kg of boron in the form of Na(2)B(4)O(7), and other that, did not receive a boron supplement. The length and weight were determined in the femur and fifth lumbar vertebra and the bone mineral content and density were assessed through densitometry, and trabecular bone volume, trabecular number, trabecular thickness, and trabecular separation with histomorphometry. The femur length and weight, and vertebra weight, and femur and vertebra bone mineral content and density were significantly lower and the trabecular separation was higher in the exercise group than in the others (p < 0.005 in all). The femur weight, bone mineral content and density, trabecular bone volume and trabecular thickness, were significantly higher in the exercise plus boron group (p < 0.005 to 0.0001). It was concluded that boron preserves bone mass in rats that have been exposed to intense exercise.

Absorptiometry, Photon↗

PubMed2001

An insight into the epidemiology of dolphin morbillivirus worldwide.

Serum samples from 288 cetaceans representing 25 species and originating from 11 different countries were collected between 1995 and 1999 and examined for the presence of dolphin morbillivirus (DMV)-specific antibodies by an indirect ELISA (iELISA) (N = 267) or a plaque reduction assay (N = 21). A total of 35 odontocetes were seropositive: three harbour porpoises (Phocoena phocoena) and a common dolphin (Delphinus delphis) from the Northeastern (NE) Atlantic, a bottlenose dolphin (Tursiops truncatus) from Kent (England), three striped dolphins (Stenella coeruleoalba), two Risso's dolphins (Grampus griseus) and a bottlenose dolphin from the Mediterranean Sea, one common dolphin from the Southwest (SW) Indian Ocean, three Fraser's dolphins (Lagenodelphis hosei) from the SW Atlantic, 18 long-finned pilot whales (Globicephala melas) and a bottlenose dolphin from the SW Pacific as well as a captive bottlenose dolphin (Tursiops aduncus) originally from Taiwan. The presence of morbillivirus antibodies in 17 of these animals was further examined in other iELISAs and virus neutralization tests. Our results indicate that DMV infects cetaceans worldwide. This is the first report of DMV-seropositive animals from the SW Indian, SW Atlantic and West Pacific Oceans. Prevalence of DMV-seropositives was 85.7% in 21 pilot whales from the SW Pacific and both sexually mature and immature individuals were infected. This indicates that DMV is endemic in these animals. The same situation may occur among Fraser's dolphins from the SW Atlantic. The prevalence of DMV-seropositives was 5.26% and 5.36% in 19 common dolphins and 56 harbour porpoise from the NE Atlantic, respectively, and 18.75% in 16 striped dolphins from the Mediterranean. Prevalence varied significantly with sexual maturity in harbour porpoises and striped dolphins; all DMV-seropositives being mature animals. The prevalence of seropositive harbour porpoise and striped dolphins appeared to have decreased since previous studies. These data suggest that DMV is not endemic within these populations, that they are losing their humoral immunity against the virus and that they may be vulnerable to new epidemics.

Animal Diseases↗

PubMed2001

River basin-related genetic structuring in an endangered fish species, Chondrostoma lusitanicum, based on mtDNA sequencing and RFLP analysis.

Chondrostoma lusitanicum is a Portuguese endemic cyprinid with a restricted distribution and reduced numbers in some basins, justifying its status as a threatened species. We examined genetic population structure using samples from throughout its geographical range in Portugal, using sequencing of b cytochrome and restriction fragment length polymorphism analysis of the NADH subunits 5 and 6. There was reduced within-population genetic variability but considerable among-population differentiation, particularly marked between both the Mira and Arade basins in the extreme south and other populations. These results confirm phylogeographic relationships suggested by previous fragmentary allozyme studies for C. lusitanicum, and are in accordance with allozyme and mitochondrial DNA data on phylogeography of coexisting cyprinid species of the genus Leuciscus. The levels of genetic divergence revealed by sequence and RFLP data showed strongly concordant patterns: geographical genetic structuring, with the definition of three distinct groups, was observed. The high values of nucleotide divergence and pairwise sequence divergence of the Mira and Arade groups, when compared with all other samples, support a distinct taxonomic status probably at the species level. Results are also discussed in relation to conservation of this highly fragmented species, in terms of Evolutionary Significant Units and Management Units.

Analysis of Variance↗

PubMed2001

Effects of silymarin on the acute stage of the trinitrobenzenesulphonic acid model of rat colitis.

The intestinal anti-inflammatory activity of several doses of silymarin was tested in the acute stage of the trinitrobenzenesulfonic acid (TNBS) model of rat colitis. The results obtained show that oral pre-treatment with 50 mg/kg of silymarin significantly attenuated macroscopic colonic damage as well as reduced colonic myeloperoxidase activity compared to non-treated colitic animals. The beneficial effect was accompanied by an improvement in the colonic oxidative status, which was altered in colonic inflammation, by preventing glutathione depletion and reducing malonyldialdehyde production. This suggests that the well known antioxidant properties of silymarin can participate in its intestinal anti-inflammatory activity. In addition, a preservation in the colonic absorptive function was also observed, and this effect can also account for the colonic protective effect observed in this model of acute colitis.

Animals↗

PubMed2001

Dietary inulin improves distal colitis induced by dextran sodium sulfate in the rat.

OBJECTIVES: Inulin stimulates intracolonic generation of butyrate and growth of lactic acid bacteria. This study investigated whether inulin protects against colitis. METHODS: Rats with dextran sodium sulfate colitis received inulin either orally (1% in drinking water, or 400 mg/day) or by enema. Matched groups received vehicle. In addition, fecal water obtained from inulin-fed rats was administered by enema to rats with colitis and compared with fecal water from control rats. Finally, rats with colitis received daily enemas of either butyrate (at 40 or 80 mmol/L) or vehicle. Inflammation was assessed by eicosanoid asssay in rectal dialysates and MPO activity in colonic tissue. Mucosal lesions were blindly scored by microscopic examination. Luminal pH was measured from cecum to rectum by a surface microelectrode. RESULTS: Oral inulin prevented inflammation, as evidenced by lower lesion scores (p < 0.05), decreased release of mediators (p < 0.05), and lower tissue MPO (p < 0.05) as compared with controls. Inulin induced acidic environment (pH <7.0) from cecum to left colon and increased counts of lactobacilli. Fecal water from inulin-fed rats also reduced scores (p < 0.05) and inflammation (p < 0.05). However, inulin or butyrate enemas had no effect. CONCLUSIONS: Oral inulin reduces the severity of dextran sodium sulfate colitis. The effect seems to be mediated by modification of the intracolonic milieu.

Animals↗

PubMed2001

Modulation of colonic barrier function by the composition of the commensal flora in the rat.

BACKGROUND AND AIMS: Altered intestinal permeability is a key pathogenetic factor of idiopathic bowel inflammation. We investigated in the rat if changes in the composition of the bowel flora can alter colonic permeability. METHODS: A colonic segment was surgically excluded from faecal transit and brought out as a loop to the abdominal wall through two colostomies. The loop was used for colonisation with specific bacterial strains after eradication of the native flora with antibiotics. Lumen to blood clearance of dextran (molecular weight 70 000) and mannitol (molecular weight 182) was measured in rats recolonised with a single bacterial strain from rat colonic origin, and in control rats whose colonic loop was kept free of bacteria by antibiotics. Actual colonisation was confirmed by culture of segment effluents. RESULTS: Colonisation with Escherichia coli, Klebsiella pneumoniae, and Streptococcus viridans significantly increased lumen to blood clearance of mannitol. Colonisation with Lactobacillus brevis had the opposite effect and reduced permeability to mannitol. Bacteroides fragilis did not induce significant changes. Permeability to dextran was not altered by any of the strains tested. CONCLUSIONS: Certain commensal bacteria can modify colonic wall permeability to luminal substances.

Analysis of Variance↗

PubMed2001

Transient osteoporosis.

Transient osteoporosis (TO) is an uncommon entity whose principal characteristic is to be a self-limited syndrome. Diagnosis is made upon clinical presentation and x-ray evidence of diffuse osteopenia around the affected joint followed by spontaneous healing after several months. When recurrent episodes occur at different times and locations it is called regional migratory osteoporosis. Magnetic resonance imaging and technetium-99 bone scan may be helpful in diagnosis during the early phase. Good results may be achieved with nonsteroidal antiinflammatory medication, protected weight bearing and physical therapy.

Diagnosis, Differential↗

PubMed2001

[Medicine and history. Concerning of the case of a man with a tumour on his forehead].

This case report is about the sickness of a 59 year old priest, politician and war veteran who died in 1844. The case history is based on the detailed report of his doctor, gathered in a diary and later published. The collected clinical data relied exclusively on touch and observation. The patient's illness started with a painful lump on his forehead that was in part excised. Surgical exploration revealed a soft tissue mass that bled easily and involved the frontal bone. In the following months, the lesion, which had been treated with complex topical medications, became ulcerated and extended to the orbit and the chin. The patient died postrated and in severe undernutrition one year after the onset of the symptoms. The case discussion, presented in the format of a clinicopathological conference, concluded that a metastasis of a renal cell carcinoma or an osseous lymphoma were the more likely diagnoses.

Argentina↗

PubMed2000

Effects on bone loss of manganese alone or with copper supplement in ovariectomized rats. A morphometric and densitomeric study.

OBJECTIVE: The aim of this study was to examine the effect of manganese (Mn) alone and with the addition of copper (Cu) in the inhibition of osteopenia induced by ovariectomy (OVX) in rats. STUDY CONDITIONS: Four lots of 100-day-old female Wistar rats were divided into experimental groups of 15 each. One group received a diet supplemented with 40 mg/kg of Mn per kilogram of feed (OVX+Mn). The second group received the same diet as the first, but with an additional 15 mg/kg of copper (OVX+Mn+Cu). The third group of 15 OVX and the fourth group of 15 Sham-OVX received no supplements. At the conclusion of the 30-day experiment, the rats were slaughtered and their femurs and fifth lumbar vertebrae were dissected. Femoral and vertebral length were measured with caliper and bones were weighed on a precision balance. The bone mineral content (BMC) and bone density (BMD) of the femur (F-BMC, mg and F-BMD, mg/cm(2)) and the fifth lumbar vertebra (V-BMC, mg and V-BMD, mg/cm(2)) were measured separately with dual energy X-ray absorptiometry. RESULTS: The F-BMD, mg/cm(2) was lower in the OVX than in the Sham-OVX group (P<0.0001) and in the other two groups receiving mineral supplements (P<0.005 in both). F-BMC, mg was significantly lower in the OVX group than in the other three (P<0.0001 in all cases). Calculations for V-BMC, mg and V-BMD, mg/cm(2) are similar to findings in the femur. CONCLUSIONS: These data show that a Mn supplement is an effective inhibitor of loss of bone mass after OVX, both on the axial and the peripheral levels, although this effect is not enhanced with the addition of Cu.

Animals↗

PubMed1999

Prospective clinical and microbiological study of pleural effusions.

A prospective clinical microbiological study of pleural fluid samples was conducted to investigate the etiology of pleural effusions and to evaluate two different methods for transport and culture of these samples. A total of 245 pleural fluid specimens were inoculated into a transport vial, an aerobic and an anaerobic blood culture vial, and a sterile tube. One hundred nine samples were from infectious patients and 128 from noninfectious patients. Gram stain had a sensitivity of 48% and a specificity of 100% as compared to culture. Of the total, 15.5% of the samples were positive for microorganisms, and 60% of the positive samples were nonpurulent pleural fluid. Single-organism growth was found in 23 samples (60.5%). Sixty-three microorganisms were isolated: 25 (39.7%) aerobic, 22 (35%) anaerobic, 13 (20.6%) mycobacteria, and three (4.7%) fungi. Of the 25 positive samples, excluding those samples that grew mycobacteria, nine (36%) were positive exclusively in the blood culture vials. Twelve organisms were isolated, only one of which did not grow in the anaerobic vial. Two (8%) samples were positive by conventional culture only, and 14 (56%) were positive by both methods. The microorganism isolation rate obtained with use of blood culture vials was significantly greater than that obtained with the conventional method of transport and culture. Sixty-three percent of the empyema patients had an associated underlying pathology, pneumonia being the most frequent. In conclusion, for microbiological study of pleural fluid, it seems appropriate to inoculate all samples, including nonpurulent samples, into both a sterile tube and an anaerobic blood culture vial.

Adolescent↗

PubMed1999

Melatonin inhibits expression of the inducible NO synthase II in liver and lung and prevents endotoxemia in lipopolysaccharide-induced multiple organ dysfunction syndrome in rats.

We evaluated the role of melatonin in endotoxemia caused by lipopolysaccharide (LPS) in unanesthetized rats. The expression of inducible isoform of nitric oxide synthase (iNOS) and the increase in the oxidative stress seem to be responsible for the failure of lungs, liver, and kidneys in endotoxemia. Bacterial LPS (10 mg/kg b. w) was i.v. injected 6 h before rats were killed and melatonin (10-60 mg/kg b.w.) was i.p. injected before and/or after LPS. Endotoxemia was associated with a significant rise in the serum levels of aspartate and alanine aminotransferases, gamma-glutamyl-transferase, alkaline phosphatase, creatinine, urea, and uric acid, and hence liver and renal dysfunction. LPS also increased serum levels of cholesterol and triglycerides and reduced glucose levels. Melatonin administration counteracted these organ and metabolic alterations at doses ranging between 20 and 60 mg/kg b. w. Melatonin significantly decreased lung lipid peroxidation and counteracted the LPS-induced NO levels in lungs and liver. Our results also show an inhibition of iNOS activity in rat lungs by melatonin in a dose-dependent manner. Expression of iNOS mRNA in lungs and liver was significantly decreased by melatonin (60 mg/kg b. w., 58-65%). We conclude that melatonin inhibits NO production mainly by inhibition of iNOS expression. The inhibition of NO levels may account for the protection of the indoleamine against LPS-induced endotoxemia in rats.

Animals↗

PubMed1999

Cartilage and serum levels of nitric oxide in patients with hip osteoarthritis.

OBJECTIVE: To assess whether nitric oxide (NO) is related to cartilage deterioration resulting from osteoarthritis, NO concentrations were analyzed in normal and deteriorated areas of cartilage obtained from femur heads of patients with primary hip osteoarthritis (HOA). METHODS: The concentration of NO in macroscopically deteriorated and non-deteriorated cartilage of femoral heads of patients with HOA at hip replacement surgery was analyzed spectrophotometrically. Serum NO levels were also determined in 16 ambulatory patients with hip OA and in healthy volunteers. RESULTS: NO levels of non-deteriorated areas of femoral head cartilage were significantly lower (3.82+/-1.30 micromol/l; mean +/- SD) than levels of deteriorated cartilage areas (11.07+/-6.48 micromol/l; p<0.01). The surgery HOA group showed serum NO levels (2.64+/-0.32 micromol/l; p<0.0001 vs. healthy group) similar to the ambulatory HOA group levels (2.56+/-0.56 micromol/l; p<0.0001 vs. healthy group). Serum NO concentrations in healthy volunteers were 1.37+/-0.55 micromol/l. CONCLUSION: This study shows increased NO levels in joint cartilage of patients with hip OA. This increase was not homogeneously distributed, but the higher NO levels were found in macroscopically deteriorated areas. The data also suggest that high NO serum levels found in patients with hip OA may be due to joint cartilage destruction.

Aged↗

PubMed1998

Metacarpal radiogrammetry by computed radiography in postmenopausal women with Colles' fracture and vertebral crush fracture syndrome.

Based on the hypothesis that the underlying osteoporotic mechanism of Colles' fracture in postmenopausal women is similar to that of other osteoporotic fractures, that is, cortical bone resorption as opposed to cancellous bone resorption, the rate of corticoendosteal bone loss was compared in 40 normal postmenopausal women [average age 68.4 +/- 7.1 years; 20 +/- 4 years since menopause (YSM)], in 35 postmenopausal women with Colles' fracture (age 69.4 +/- 7.5 years, 22 +/- 8 YSM), in 35 normal postmenopausal women with vertebral crush fracture (age 69.4 +/- 7.5 years, 22 +/- 8 YSM, and in 35 normal premenopausal women (age 36.1 +/- 7.9 years). Radiogrammetry by digital radiography of the second metacarpal was used to measure external (ED) and internal (ID) diameter, cortical thickness (CCT), cortical area (CA), and the ratio of cortical area to total area (CA/TA). The ID values of the groups of postmenopausal women were subtracted from the ID value of the premenopausal women and the result was divided by YSM to obtain the rate of corticoendosteal resorption/year (DeltaC), CA resorption year (DeltaCA) and CA/TA resorption/year (DeltaCA/TA). ID, DeltaC, DeltaCA, and DeltaCA/TA all were larger in the postmenopausal women with Colles' and vertebral crush fractures than in the normal postmenopausal women (ANOVA: all P < 0.0001). ID, CCT, DeltaC, CA, DeltaCA, and DeltaCA/TA did not differ between the two groups of postmenopausal women with fractures. DeltaC was 87% greater in postmenopausal women with vertebral crush fracture and 116% greater in women with Colles' fracture than in normal postmenopausal women. These results indicate that the loss of cortical bone is an important factor in Colles' fracture in postmenopausal women.

Adult↗

PubMed1998

Stimulation of transforming growth factor beta1 by enteric bacteria in the pathogenesis of rat intestinal fibrosis.

BACKGROUND & AIMS: Bacteria and their products stimulate inflammatory responses. Certain mediators, such as transforming growth factor beta1 (TGF-beta1), induce collagen synthesis. Excess collagen deposition results in bowel strictures. The aim of this study was to investigate the role of bacteria and TGF-beta1 in the pathogenesis of intestinal fibrosis. METHODS: In rats with colitis, the effects of bowel decontamination with antibiotics on TGF-beta1, tumor necrosis factor alpha (TNF-alpha), and collagen content in colonic tissue were studied. In normal rats, bacteria of the predominant flora were inoculated into the colonic wall. The effect of neutralizing antibody to TGF-beta1 on tissue collagen deposition was studied. RESULTS: Rats with chronic colitis showed increased levels of TGF-beta1, TNF-alpha, and collagen in the tissue and a high rate of bowel strictures. Antibiotic treatment significantly prevented the increase in TGF-beta1 and collagen and the formation of strictures. Inoculation of bacterial suspensions into the colonic wall increased tissue TGF-beta1 and collagen content. Neutralizing antibody to TGF-beta1 prevented collagen deposition. Colonic wall inoculations with single anaerobic strains (Clostridium ramosum, Bacteroides fragilis, and Bacteroides uniformis), but not with aerobes, induced collagen deposition. CONCLUSIONS: Certain strains of the common flora stimulate TGF-beta1 and induce deposition of collagen in the colonic wall.

Animals↗

PubMed1998

Derangement of mucosal barrier function by bacteria colonizing the rat colonic mucosa.

BACKGROUND: Interaction between gut flora and the intestinal barrier may involve changes in permeability. METHODS: Rats with a colonic segment excluded from faecal transit were surgically prepared. Matched groups were either kept on luminal antibiotics to prevent colonization of the segment or recolonized with mixed rat flora. Permeability to low-dose trinitrobenzenesulphonic acid (TNBS) or trinitrophenol (TNP), and mucosal injury by the compounds at a high dose were tested in antibiotic and recolonized rats (the compounds differ in water solubility but share a common antigenic domain). RESULTS: Lumen to blood clearance of the hydrophilic probe (TNBS) was faster in recolonized than in antibiotic rats. The hydrophobic compound TNP was absorbed at faster rates than TNBS, but there was no difference between antibiotic and recolonized rats. Instillation of TNBS at a high dose induced mucosal release of inflammatory mediators and tissue myeloperoxidase accumulation in recolonized rats but not in antibiotic rats. Large necrotic lesions with submucosal involvement after TNBS were only observed in recolonized rats. In contrast, TNP induced mucosal inflammation and large lesions with submucosal necrosis both in recolonized and in antibiotic rats. CONCLUSION: Colonizing bacteria may increase intestinal permeability to hydrophilic compounds and render the mucosa susceptible to injury.

Animals↗

PubMed1998

Modification of nitric oxide synthase activity and neuronal response in rat striatum by melatonin and kynurenine derivatives.

Tryptophan is mainly metabolized in the brain through methoxyindole and kynurenine pathways. The methoxyindole pathway produces (among other compounds) melatonin, which displays inhibitory effects on human and animal central nervous systems, including a significant attenuation of excitatory, glutamate-mediated responses. The kynurenine pathway produces kynurenines that interact with brain glutamate-mediated responses. Nitric oxide (NO) increases glutamate release, and melatonin and kynurenines may act via modification of NO synthesis. In the present study, the effects of melatonin and four synthetic kynurenines were studied on the activity of rat striatal nitric oxide synthase (NOS) and on the response of rat striatal neurons to sensorimotor cortex (SMCx) stimulation, a glutamate-mediated response. Melatonin inhibited both NOS activity and the striatal glutamate response, and these effects were dose-related. Compound A (2-acetamide-4-(3-methoxyphenyl)-4-oxobutyric acid) did not inhibit NOS activity but inhibited the striatal response similarly to melatonin. Compound B (2-acetamide-4-(2-amino-5-methoxyphenyl)-4-oxobutyric acid) was more potent than melatonin in inhibiting both NOS activity and the striatal response. Compound C (2-butyramide-4-(3-methoxyphenyl)-4-oxobutyric acid) did not change NOS activity, but increased the striatal response. Compound D (2-butyramide-4-(2-amino-5-methoxyphenyl)-4-oxobutyric acid) showed potent inhibitory effects on both NOS activity and striatal glutamate-mediated response. A structure-related effect of the kynurenine derivatives was observed, and those with an amino group in position 2 of the benzenic ring had more potent effects than melatonin itself in inhibiting striatal NOS activity and the response of striatal neurons to SMCx.

Animals↗

PubMed1998

Antitumor necrosis factor therapy in rat chronic granulomatous colitis: critical dose-timing effects on outcome.

Inhibition of tumor necrosis fact (TNFalpha) is of potential benefit in the treatment of chronic inflammatory conditions. However, TNFalpha plays an important role in host defenses against infection, and blocking TNFalpha production may also have adverse effects. We tested the efficacy and safety of anti-TNFalpha therapy in experimental colitis induced by trinitrobenzenesulfonic acid. We cultured colonic wall specimens for bacterial growth and measured native TNFalpha protein synthesis in colonic tissue at days 0, 1, 4, 10 and 18 after induction of colitis. Anti-TNFalpha therapy (monoclonal g1 immunoglobulin, 15 mg/kg i.p., every third day) was started on either day 4 or day 10 after induction of colitis. On day 18, we measured the release of inflammatory mediators and scored colonic lesions. In acute lesions, several species of the common flora were grown, including Streptococcus, Staphylococcus, Bacteroides, clostridia and enterobacteria. In chronic lesions, only enterobacteria, clostridia and lactobacilli were isolated. TNFalpha production by inflamed colonic tissue was increased in both acute and chronic lesions. Anti-TNFalpha therapy induced a significant decrease in the release of inflammatory mediators and histopathological remission when treatment started on day 10. However, anti-TNFalpha therapy increased eicosanoid release and lesion scores when treatment started on day 4. In conclusion, acute colonic lesions showed polymicrobial infection. Anti-TNFalpha therapy induced remission of chronic intestinal inflammation, but early treatment did not prove effective.

Animals↗