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L Martinez

Publications and source records attributed to L Martinez.

At least 19 recordsLinked to original sources
PubMed2005

Quality specifications for seminal parameters based on the state of the art.

BACKGROUND: The aim of this study was to calculate the analytical goal for seminal parameters based on the state of the art, and then to compare these specifications with those previously obtained by our group based on biological variation. METHODS: All data used for analysis were derived from the Spanish programme of external quality control on semen analysis. Over 90 laboratories participated from 1999 to 2003. Using graphs of the state of the art, we also determined the numbers of laboratories that achieved quality specifications. RESULTS: The total allowable error calculated using state of the art graphs is similar to that calculated using biological variation for concentration and total motility. However, it is much higher for morphology and rapidly progressive motility. Over 80% of the laboratories achieved the minimum quality specification based on biological variation for concentration, total and progressive motility. However, only approximately 30% of the laboratories achieved the minimum quality specification based on biological variation for morphology and rapidly progressive motility. CONCLUSIONS: The study enabled us to identify the state of the art of analytical performance for seminal parameters, and revealed the difficulty inherent in meeting the quality specifications based on biological variation.

Andrology↗
PubMed2005

Sero-prevalence of Taenia solium cysticercosis and Taenia solium taeniasis in California, USA.

OBJECTIVES: Taenia solium Cysticercosis is a leading cause of epilepsy and neurological disability in the developing world. It is caused by ingestion of the eggs of the tapeworm, T. solium Taeniasis. The prevalence of either T. solium Cysticercosis or T. solium Taeniasis in the United States in populations at risk is poorly understood. The primary objectives of this study are to perform the first study of the sero-prevalence of T. solium Cysticercosis and T. solium Taeniasis in an at-risk community in the USA, specifically rural Southern California; identify T. solium Taeniasis positive individuals, and treat positive individuals for the tapeworm T. solium Taeniasis. METHODS: Community based sero-prevalence study of antibodies to T. solium Cysticercosis and T. solium Taeniasis in 449 subjects living in a federally funded, predominantly Hispanic residential community; and in two migrant farm worker camps in rural Ventura County, California, USA. For this study, fingerstick blood samples were obtained. Serum immunoblots for both T. solium Cysticercosis and T. solium Taeniasis were performed. RESULTS: The sero-prevalence of T. solium Cysticercosis was 1.8% and the sero-prevalence of T. solium Taeniasis by serum immunoblot was 1.1%. Taenia solium Cysticercosis and T. solium Taeniasis antibodies were not detected in children. The sero-prevalence of T. solium Taeniasis was highest in the migrant farm worker community. Handwashing frequency was correlated with T. solium Taeniasis sero-positivity. CONCLUSION: The sero-prevalence of T. solium Cysticercosis and T. solium Taeniasis in this population, as detected by serum immunoblot, approximates the prevalence in some endemic areas of Latin America. Importantly, most patients likely had prior exposure, not active infection. This study establishes for the first time, the relative sero-prevalence of T. solium Cysticercosis and T. solium Taeniasis in at-risk populations in the United States.

Adolescent↗
PubMed2005

[Evaluation of the prevalence and management of normocholesterolaemic and non coronary hypertensives in France].

We performed a study amongst hypertensive patients who consulted French general practitioners in the Sentinelles network. Firstly, the significance of this population in mainland France was quantified by keeping a register of all hypertensive patients aged over 40 years seen in a general practice consultation, and secondly the distribution of risk factors and management of normocholesterolaemic (total cholesterol < or = 2.5 g/l) without lipid lowering treatment and non coronary patients was described more precisely. Analysis of the population of 7864 hypertensives from this register showed that on average one doctor saw 3 hypertensive patients a day and that about half of them (54%) were normocholesterolaemic, non coronary patients. Analysis of this sub-population of 2519 patients showed that 19.9% of them had at least 3 of the other cardiovascular risk factors described in the ASCOT study (Anglo-Scandinavian Cardiac Outcomes Trial) and that 39.5% had controlled hypertension according to the New York Heart Association classification. The extrapolated number of hypertensive, non coronary patients who were normocholesterolaemic without lipid lowering treatment was estimated as 4.6 million (4.1:5.1) for the whole of France.

Aged↗
PubMed2004

Pax3 mRNA is decreased in the hearts of rats with experimental diaphragmatic hernia.

Rats with nitrofen-induced congenital diaphragmatic hernia (CDH) have heart hypoplasia and cardiovascular malformations. The mechanism of action of nitrofen involves changes in neural crest signaling. Pax3 function is required for cardiac neural crest cells to complete their migration to the developing heart. The aim of this study was to examine whether Pa x 3 expression is changed at two gestational endpoints in rat embryos or fetuses exposed to nitrofen. On day E9.5 of gestation, pregnant rats received either 100 mg of nitrofen (n=10) or vehicle alone (control, n=10). The fetuses were recovered on E15 or E21. Their hearts were dissected out and weighed. Pax3 mRNA expression was determined by real-time polymerase chain reaction. We used two-tailed Student's t-tests to compare groups, with a threshold of significance of p<0.05. Compared with controls, nitrofen-exposed fetuses had heart hypoplasia in terms of heart/body weight ratio (0.62+/-0.10% vs. 0.77+/-0.17%, p<0.05). Pax3 mRNA expression in the heart was significantly decreased on E15 in nitrofen-treated embryos (32.94+/-17.11 U vs. 55.09+/-11.56 U, p<0.05), and it was still decreased, although not significantly, in the hearts of nitrofen-exposed fetuses recovered on E21 (15.67+/-5.56 U vs. 20.51+/-5.92 U, not significant). In conclusion, Pax3 is underexpressed in the hearts of nitrofen-exposed embryonal rats before the end of gestation. The mechanism of action of Pax3 should be further investigated because it could be one of the targets for future prenatal transplacental intervention.

Animals↗
PubMed2004

Bacterial translocation in acute rejection after small bowel transplantation in rats.

Acute rejection after small bowel transplantation (SBTx) may facilitate bacterial translocation (BT) and subsequent changes in the liver, spleen, and lungs. This study investigated whether BT occurs after acute rejection and whether this is followed by changes in the structure of the intestine and the phagocytic organs interposed between the gut and the general circulation. Orthotopic SBTx was performed in allogeneic (ALLO) rat-strain combinations (BN-Wistar, n=5). For comparison we used syngeneic SBTx (SYN) (BN-BN, n=6) controls. Animals were sacrificed on postoperative day 7. Mesenteric lymph nodes and portal and caval blood were cultured for aerobes and anaerobes. Escherichia coli beta-galactosidase DNA was assessed by polymerase chain reaction in the blood samples. Intestine, liver, spleen, and lung protein and DNA contents were measured. Histologic changes were graded according to standard criteria of acute rejection. For comparisons we used chi(2) and nonparametric Mann-Whitney test with a threshold of significance of p<0.05. ALLO rats lost more weight after SBTx than SYN rats (-13.02+/-4.39% vs. -8.04+/-5.08% of preoperative weight), although the difference was not significant (ns). A variable degree of graft rejection was histologically demonstrated in all ALLO rats, and DNA/protein content in the graft was significantly higher in this group (0.245+/-0.85 vs. 0.134+/-0.21, p<0.05). Gram-negative enteric bacteria were found in 4/5 ALLO and 4/6 SYN rats (ns), and aerobic Gram-positive bacteria in 2/5 and 3/6 (ns), respectively. Anaerobic growth occurred in mesenteric lymph nodes in one ALLO rat and in the bloodstream in another one. E. coli DNA was isolated in none of the ALLO but in two SYN rats (ns). BT was frequent after SBTx in both syngeneic and allogeneic strain combinations. Contrary to our expectations, BT after SBTx was not higher in ALLO group rats. However, anaerobic germs were isolated only in this group.

Acute Disease↗
PubMed2004

Decrease of parafollicular thyroid C-cells in experimental esophageal atresia: further evidence of a neural crest pathogenic pathway.

Adriamycin-induced experimental esophageal atresia (EA) is often associated with malformations of neural crest (NC) origin, such as abnormal pharyngeal pouch derivatives like the thymus and the parathyroids. The aim of the present study was to examine whether NC-derived thyroid C-cells were abnormal in a rat model. Pregnant rats received intraperitoneally either 2 mg/kg Adriamycin (EA) or vehicle (controls) on days 8 and 9 of gestation. Fetuses were recovered on day 21, and blocks including the trachea and thyroid were fixed in formalin, coronally sectioned at 3-mum widths, and stained with standard hematoxylin and eosin until the largest area of thyroid was reached. From this point on, the 1st, 10th, and 20th slices were immunohistochemically stained with anti-calcitonin antibody. Positively-stained cells in each section of the gland were counted using a computer-assisted image analysis method, and the results were averaged. The distribution of the cells within the gland was assessed as well. Comparisons between EA and control rats were made by nonparametric tests with a significance threshold of p<0.05. The number of C-cells was dramatically reduced in EA animals compared with controls (32.4+/-36 vs. 92.3+/-60.5, p<0.001). Histology of the thyroid was similar in both groups, but the distribution of positive C-cells within the gland followed an abnormal pattern in EA rats. Adriamycin causes a pattern of NC-derived malformations, including a severe decrease in thyroid C-cells accompanied by abnormal distribution or migration patterns. These results represent further evidence of the involvement of NC organogenic control dysregulation in the pathogenesis of EA and its associated malformations. The similarities between the rat model and the clinical picture strongly support investigating other subclinical NC-derived anomalies in patients with EA.

Animals↗
PubMed2004

[Cadasil].

Explore the source record for details and available documents.

CADASIL↗
PubMed2004

Expression of integrin fraction and adhesion molecules on human granulosa cells and its relation with oocyte maturity and follicular steroidogenesis.

PURPOSE: To study the correlation between the expression of integrin fractions and adhesion molecules on granulosa cells (GC) and follicular development. METHODS: GC and follicular fluid (FF) were obtained at oocyte retrieval for ICSI. Expression of adhesion molecules on GC was studied by flow cytometry. Statistics were evaluated using the Student t test and simple linear regression analysis. RESULTS: alpha5 integrin fraction was significantly (p < 0.01) higher, while alpha6 fraction and CD9 were significantly (p < 0.01 and p < 0.001, respectively) lower in GC from FF with metaphase II oocytes. A direct significant correlation was observed between FF progesterone and the alpha5 expression on GC (r = 0.54). In contrast, an inverse significant correlation was observed between FF progesterone level and the expression of alpha6 and CD9 (r = -0.40 and -0.41, respectively). CONCLUSIONS: The expression pattern for integrin fractions and adhesion molecules may be of predictive value in assessing the state of differentiation of the human follicle.

Estradiol↗
PubMed2004

Variants of U1 small nuclear RNA assemble into spliceosomal complexes.

In this study, the existence of additional U1 snRNA variants in the posterior silk gland of the Bombyx mori Nistari strain from India was investigated. Three new U1 variants were detected. One of the new isoforms (U1 SG1) was found to be preferentially assembled into high molecular weight spliceosomal complexes in comparison with the total cellular lysate RNA control. Structural and nucleotide differences were examined in these new isoforms and compared with the previously reported U1 variants. Free energy (Delta G) values for the entire U1 snRNA secondary structures as well as the individual stem/loops (I, II, III and IV) domains of the isoforms were estimated to determine their structural stability.

Animals↗
PubMed2003

Aggressive conservative treatment of esophageal perforations in children.

BACKGROUND/PURPOSE: In contrast with adult patients in whom surgical closure of the defect is preferred, nonoperative treatment has been the usual approach for esophageal perforation (EP) in children. This report aims to assess whether this strategy stands the passage of time. METHODS: We reviewed retrospectively the charts of 17 patients aged 5.3 +/- 0.9 years (mean +/- SD) treated at our institution for EP between 1991 and 2001. RESULTS: Nineteen episodes of EP were caused by stricture dilation in 9 cases, foreign body extraction in 3, and blunt trauma and sclerosis of varices in 2 cases each. The remaining child had multiple gastrointestinal perforations in the course of chemotherapy for leukemia. Vigorous treatment, consisting of nasopharyngeal aspiration, wide spectrum antibiotics, prompt drainage of effusions and either parenteral or infraesophageal nutritition, was implemented immediately after diagnosis. Perforations were closed without direct surgery in 18 of 19 episodes (16 of 17 children). One or more pleural drains were inserted in 12 cases, and pericardial drainage was required once. Seven gastrostomies, 2 jejunostomies, and one esophagostomy were performed. Several major abdominal operations were necessary to repair concomitant lesions in a child who sustained severe blunt abdominal trauma and in the patient with leukemic perforations. All patients survived, and all recovered esophageal function. However, 2 with intractable lye strictures ultimately required esophageal replacement. The only patient in whom a direct approach for esophageal necrosis due to variceal endosclerosis was unavoidable, lost her organ and had a retrosternal colonic interposition after a successful portosystemic shunt. Excluding patients with other concomitant lesions and the patient who underwent surgery, median length of stay was 11 days (range, 6 to 47). CONCLUSIONS: Prompt and aggressive nonoperative treatment of esophageal perforations in children allows survival with conservation of the organ in most cases and remains, in the authors' hands, the first therapeutic choice at this age.

Abdominal Injuries↗
PubMed2001

Altered content and modulation of soluble guanylate cyclase in the cerebellum of rats with portacaval anastomosis.

It is shown that the glutamate-NO-cGMP pathway is impaired in cerebellum of rats with portacaval anastomosis in vivo as assessed by in vivo brain microdialysis in freely moving rats. NMDA-induced increase in extracellular cGMP in the cerebellum was significantly reduced (by 27%) in rats with portacaval anastomosis. Activation of soluble guanylate cyclase by the NO-generating agent S-nitroso-N-acetyl-penicillamine and by the NO-independent activator YC-1 was also significantly reduced (by 35-40%), indicating that portacaval anastomosis leads to remarkable alterations in the modulation of guanylate cyclase in cerebellum. Moreover, the content of soluble guanylate cyclase was increased ca. two-fold in the cerebellum of rats with portacaval anastomosis. Activation of soluble guanylate cyclase by NO was higher in lymphocytes isolated from rats with portacaval anastomosis (3.3-fold) than in lymphocytes from control rats (2.1-fold). The results reported show that the content and modulation of soluble guanylate cyclase are altered in brain of rats with hepatic failure, resulting in altered function of the glutamate-NO-cGMP pathway in the rat in vivo. This may lead to alterations in cerebral processes such as intercellular communication, circadian rhythms, including the sleep-waking cycle, long-term potentiation, and some forms of learning and memory.

Animals↗
PubMed2001

Architecture and function of the gastroesophageal barrier in the piglet.

We describe the anatomy and function of the gastroesophageal barrier in the piglet. Male piglets underwent dissection (N = 6) and gastroesophageal muscle layer histometry (N = 6). Sedated, nonintubated animals (N = 13) underwent four-probe perfusion esophageal manometry and the pressure profiles were related to the muscular thickness in the four quadrants. Hiatal and gastroesophageal anatomy are similar to our own. The muscle is thicker at the point where the clasp (on the right side) and sling fibers (on the left) concentrate. The pressure profiles were axially and radially asymmetric in coincidence with the thickness variations of the corresponding muscle layers. Sphincteric pressure was recorded as a plateau, whereas diaphragmatic crural pressure appeared as phasic oscillations in synchrony with respiration. The sphincter relaxed upon deglutition. In conclusion, the gastroesophageal structure and physiology are so similar in men and piglets that piglets are excellent models for research in this area.

Animals↗
PubMed2001

Chromatin status in human ejaculated spermatozoa from infertile patients and relationship to seminal parameters.

The aim of this study was to evaluate the chromatin status in different groups of patients. Five groups of men were selected: pre-vasectomy; male factor infertility; varicocele; immunological male infertility; and idiopathic infertility. Chromatin status was evaluated using flow cytometry after staining the DNA with the fluorochrome propidium iodide. Differences were observed in the state of sperm chromatin between the male factor and varicocele groups with respect to the others. These two groups presented poorer quality chromatin, as evidenced fundamentally by a lower degree of condensation. These deficiencies in chromatin status were usually accompanied by alterations in the other standard parameters of semen analysis. Individuals who are infertile due to male factor and those presenting varicocele have spermatozoa with less condensed chromatin which might, in part, explain their sterility.

Chromatin↗
PubMed2001

WHP/ISBRA study on state and trait markers in alcoholism.

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chair was Boris Tabakoff. The presentations were (1) Overview of the WHO/ISBRA study on state and trait markers in alcoholism, by Boris Tabakoff; (2) Biochemical markers of acute and chronic drinking: Results of the WHO/ISBRA study, by Anders Helander; (3) The impact of country of recruitment and body mass index on biological marker dose-response curves in the WHO/ISBRA Study, by Kate M. Conigrave; (4) Relationship of body water to carbohydrate-deficient transferrin measures, by Larry Martinez; and (5) Platelet adenylyl cyclase activity as a trait marker of alcohol dependence, by Paula L. Hoffman.

Adenylyl Cyclases↗
PubMed2000

Mini-review: history of organized teratology information services in North America.

A history of the Organization of Teratology Information Services (OTIS) is presented in context of the history of teratology information services. During the late 1970s, teratology information services grew out of the need for current and accurate information about fetal effects of environmental exposures in pregnancy. Over the next decade, teratology information services networked and collaborated, developing their own professional organization. A description of the activities of OTIS is described.

Female↗
PubMed2000

Identification of known and novel genes in activated monocytes from patients with rheumatoid arthritis.

OBJECTIVE: To define gene activation patterns of monocytes (MO) in patients with rheumatoid arthritis (RA). METHODS: A complementary DNA (cDNA) library was constructed from first-leukapheresis MO obtained from an RA patient with active disease; 32P-labeled cDNA from first-leukapheresis MO (activated pool) and third-leukapheresis MO (nonactivated pool) were used as probes for differential hybridization. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to assess gene activation in MO from an additional 26 RA patients and 6 normal controls. RESULTS: Subtraction of genes from first- and third-leukapheresis MO resulted in 482 differentially expressed clones. In first-leukapheresis MO, these clones included the following: 1) interleukin-1alpha (IL-1alpha), IL-1beta, IL-6, tumor necrosis factor alpha, growth-related oncogene alpha (GROalpha)/melanoma growth-stimulatory activity, macrophage inflammatory protein 2/GRObeta, ferritin, alpha1-antitrypsin, lysozyme, transaldolase, Epstein-Barr virus-encoded RNA 1 (EBER-1)/EBER-2-associated-protein, thrombospondin 1, an angiotensin receptor II (ATRII) C-terminal homolog, and RNA polymerase II elongation factor (elongin); 2) two clones homologous to functionally undefined genes (BSK-67 and BSK-83); and 3) three unknown cDNA sequences (BSK-66, 80, 89). In third-leukapheresis MO, the clones included differentiation genes (HOX-B3, thymosin-beta4, PU.1, glucocerebrosidase, MEL-18, and glucose-6-phosphate dehydrogenase) and 3 unknown/functionally undefined sequences. Differential expression of most genes from the activated pool was confirmed in leukapheresis samples from 2 additional RA patients. In MO from RA patients, not only were IL-1beta and the ATRII homolog significantly overexpressed (maximum 36-fold), but also 4 of the unknown/functionally undefined genes (maximum 102-fold). Notably, messenger RNA levels of BSK-89 correlated positively with the erythrocyte sedimentation rate (ESR), whereas those of BSK-83 correlated negatively with the ESR and C-reactive protein level. CONCLUSION: The combined strategy of gene subtraction and semiquantitative RT-PCR may allow the definition of MO activation patterns during different disease phases (including therapy-induced remission) and the identification of novel MO genes with pathogenetic relevance in RA.

Adult↗