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Biomedical subjects

M Martinez

Publications and source records attributed to M Martinez.

At least 217 records · Page 12Linked to original sources

Neuropeptides and interleukin-6 in human joint inflammation relationship between intraarticular substance P and interleukin-6 concentrations.

Plasma and synovial fluid concentrations of interleukin-6 (IL-6), using an enzyme-linked immunosorbent assay, as well as immunoreactive levels of calcitonin gene-related peptide (CGRP), substance P and vasoactive intestinal peptide (VIP) were measured in 18 patients with rheumatoid arthritis and 20 with osteoarthritis of the knee. The concentrations of IL-6 were elevated in both plasma and synovial fluids from patients with rheumatoid arthritis whereas higher levels of substance P-, CGRP- and VIP-like immunoreactivities were found in the synovial fluid, but not in plasma, from patients with rheumatoid arthritis when compared with those in osteoarthritis. Furthermore, IL-6 and substance P levels in synovial fluid were significantly correlated both in rheumatoid arthritis and osteoarthritis patients. Our data seem to support the idea of an important role shared by neuropeptides and IL-6 in the pathogenesis of human inflammatory joint disease.

Arthritis, Rheumatoid↗

Blood polyunsaturated fatty acids in patients with peroxisomal disorders. A multicenter study.

The purpose of the study was to compare the polyunsaturated fatty acid (PUFA) status in patients with X-linked adrenoleukodystrophy or adrenomyeloneuropathy (X-ALD/AMN) with that in disorders of peroxisome biogenesis (PB). Total fatty acids and plasmalogens were quantified in plasma and red cells from 28 patients with X-ALD/AMN, 26 patients with generalized peroxisomal disorders, and 37 controls. Total fatty acid methyl esters and plasmalogen dimethyl acetals were obtained by direct transmethylation and separated by capillary column gas chromatography. The results confirm previous findings in that docosahexaenoic acid (DHA, 22:6n-3) was greatly decreased in both plasma and erythrocytes from patients with PB disorders. When nutritional conditions were adequate, patients with X-ALD/AMN had normal levels of DHA. A highly significant positive correlation was found between the levels of DHA and those of plasmalogens in peroxisomal patients. As in other tissues, the parent n-6 fatty acid, linoleic acid (LA, 18:2n-6) was significantly increased in red cells from PB patients, whereas arachidonic acid (20:4n-6) was virtually within normal limits. In clear contrast to red cells and other tissues, arachidonate was significantly lower in plasma from PB patients. The decrease in plasma arachidonate and the high tissue levels of LA suggest a defect of delta 6 desaturase and/or delta 5 desaturase in PB patients. The n-6 fatty acids were normal in X-ALD/AMN patients. The present data show that X-ALD/AMN patients do not have the profound PUFA alterations that PB patients have, at least in blood.

Adolescent↗

Pseudoautosomal region in schizophrenia: linkage analysis of seven loci by sib-pair and lod-score methods.

In a previous study, we reported a nonrandom segregation between schizophrenia and the pseudoautosomal locus DXYS14 in a sample of 33 sibships. That study has been extended by the addition of 16 new sibships from 16 different families. Data from six other loci of the pseudoautosomal region and of the immediately adjacent part of the X specific region have also been analyzed. Two methods of linkage analysis were used: the affected sibling pair (ASP) method and the lod-score method. Lod-score analyses were performed on the basis of three different models--A, B, and C--all shown to be consistent with the epidemiological data on schizophrenia. No clear evidence for linkage was obtained with any of these models. However, whatever the genetic model and the disease classification, maximum lod scores were positive with most of the markers, with the highest scores generally being obtained for the DXYS14 locus. When the ASP method was used, the earlier finding of nonrandom segregation between schizophrenia and the DXYS14 locus was still supported in this larger data set, at an increased level of statistical significance. Findings of ASP analyses were not significant for the other loci. Thus, findings obtained from analyses using the ASP method, but not the lod-score method, were consistent with the pseudoautosomal hypothesis for schizophrenia.

Family↗

Patterns of cocaine binging: effect on pregnancy.

OBJECTIVE: The purpose of this study was to determine how cocaine and crack binging affected perinatal complications. STUDY DESIGN: Between Jan. 1 and Dec. 31, 1989, patterns of cocaine-crack binging and perinatal consequences in 905 pregnant women from multiethnic, multiracial, inner-city populations were studied. Binging cycles reflect the chaotic lifestyle of drug abuse and multiple obstetric at-risk cofactors as integral parts of binging and are more accurately defined than amount of drugs consumed. RESULTS: Binging patterns in 905 pregnant women who use cocaine-crack as their primary drug were as follows: group 1, 78 women with "erratic" binging that is variable in intervals, duration, and amounts but who are very aggressive drug seekers; group 2, 67 women who binged daily; group 3, 760 women who binged in cycles at 3-, 5-, 7-, or > 7-day intervals. Binges ranged from 26.4 to 34.4 hours. Complications were proportional to the frequency of binging, (linear association p < 0.0007). The prematurity rate in group 1 was unexpectedly as high as that in group 2 (35.9% vs 34.3%). Acute problems (vaginal bleeding 21.8%, abruptio placentae 14.3%, stillbirths 20.5%) were most significant in group 1, while chronic problems (small-for-gestational-age infants 32.8%, systemic infections 31.3%, anemia 35.6%, and low maternal weight [< 100 pounds] 32.8%) were more significant in groups 2 and 3. Odds ratios show that prematurity, abruptio placentae, and vaginal bleeding were two to three times more likely to occur if test results for cocaine were positive at delivery. However, in group 1 the likelihood of abruptio placentae was unchanged whether toxicologic test results were positive (14.3%) or negative (14.0%), reflecting the role of cofactors in binging. CONCLUSION: Erratic use of cocaine-crack results in perinatal complications that are as severe as those occurring with daily binging but the patterns differ. Cofactors play a significant role in outcomes.

Adult↗

Chemical and 13C NMR studies of Enterolobium cyclocarpum gum and its degradation products.

A structural study of the gum exudate from Enterolobium cyclocarpum has been carried out using chemical methods and 13C NMR spectroscopy. The results reveal that the structure of this gum is essentially a beta-(1-->3)-galactan. Some galactoses are 6-O-linked and others also occur as terminal residues. There is evidence that supports the presence of alpha-L-arabinofuranose and beta-L-arabinopyranose. beta-D-Glucuronic acid may be present as terminal and internal residues, while the 4-O-methyl-alpha-D-glucuronic acid residues exist predominantly in internal positions.

Arabinose↗

No major role for the dopamine D2 receptor Ser-->Cys311 mutation in schizophrenia.

A new structural polymorphism (Ser311/Cys311) in the dopamine D2 receptor (DRD2) gene has recently been reported to be associated with schizophrenia, particularly in patients with a positive family history of schizophrenia (Arinimi et al., 1994). However these findings remain controversial (Asherson et al., 1994; Nanko et al., 1994; Nöthen et al., 1994; Shaikh et al., 1994). Thus we investigated the role of the Cys311 mutation in schizophrenia using both association and family studies. First, we screened for the Cys311 mutation in 113 unrelated Caucasian schizophrenics (mean age 42 +/- 0.6; 34 females and 79 males) including 25 familial cases, and 184 unrelated controls (mean age 49 +/- 0.5, 74 females and 110 males) free of any psychiatric disorders. Diagnoses were ascertained according to DSM-III criteria (Campion et al., 1994). All patients and controls were native to the area of Rouen.

Alleles↗

Fixed drug eruption caused by sulfaguanidine.

We report a patient who developed a fixed drug eruption (FDE) due to sulfaguanidine. This drug has not been previously implicated as a cause of FDE. The diagnosis was confirmed by an oral provocation and a biopsy of the lesion. Oral provocations with other sulfonamides, sulfamethoxazole and sulfadiazine, were well tolerated.

Administration, Oral↗

Modulation of phospholipase A2 activity by membrane-active peptides on liposomes of different phospholipid composition.

To determine the influence of variations in both lipid species and lipid packing on phospholipase A2 (PLA2) hydrolytic activity, the activities of two PLA2 isolated from Crotalus molossus molossus venom, were followed on unilamellar liposomes modified by membrane-active peptides. Enzymatic activity was compared with cytolytic activity on human and mouse lymphocytes. Phosphatidylcholine liposomes were hydrolysed better than liposomes containing acidic phospholipids (phosphatidylserine, phosphatidic acid or cardiolipin) or phosphatidylethanolamine. Both membrane-active peptides, cardiotoxin and thionin, inhibited the PLA2 activity on phosphatidylcholine liposomes. The activities of the enzymes were profoundly enhanced on thionin-pretreated liposomes containing phosphatidylserine, and on cardiotoxin-pretreated liposomes containing cardiolipin or phosphatidic acid. Both cardiotoxin and thionin facilitated the cytolytic activities of PLA2 on both human and mouse lymphocytes. Cytolytic activity correlated well with esterase activity. It is proposed that the complex dynamic structure of cell membranes renders a variety of substrate configurations that transiently affect PLA2 activity.

Animals↗

Alterations of anorectic cytokine levels from plasma and cerebrospinal fluid in idiopathic senile anorexia.

Plasma and cerebrospinal fluid (CSF) concentrations of two well-known satiety cytokine peptides have been measured in elderly persons with idiopathic anorexia and normal weight healthy subjects in a similar age range. Plasma and CSF levels of tumor necrosis factor alfa (TNF alpha) and interleukin-1 beta (IL-1 beta) were assayed by commercially available kits. Elderly under-weight anorectic patients had significantly lower levels of TNF alpha but unchanged concentrations of IL-1 beta in both plasma and CSF when compared to controls. In addition to significantly lower levels of TNF alpha in CSF, we found a positive correlation between the body mass index and CSF TNF alpha concentrations (r = 0.61, P < 0.05) in the anorectic group. CSF IL-1 beta concentrations showed a significant negative correlation with plasma albumin levels in senile anorectics (r = -0.66, P < 0.05) but not in controls. On the basis of our findings, we conclude that a decrease in plasma and CSF TNF alpha concentrations could have beneficial effects for the primary anorexia of aging both at central level to offset anorexia and at peripheral sites decreasing tissue catabolism.

Aged↗

Alterations in plasma and cerebrospinal fluid levels of neuropeptides in idiopathic senile anorexia.

Plasma and cerebrospinal fluid (CSF) concentrations of three well-known satiety neuropeptides, cholecystokinin (CCK), somatostatin and calcitonin gene-related peptide (CGRP), along with two powerful orexigenic neuropeptides, neuropeptide Y (NPY) and beta-endorphin have been measured in elderly persons with idiopathic anorexia and normal weight healthy subjects in a similar age range. Plasma and CSF immunoreactivity levels of the two main fractions of CCK (CCK8s and CCK33) after being separated by HPLC were measured by a radioimmunoassay (RIA) developed in our laboratory, whereas the other neuropeptides were assayed by commercially available RIA kits. Elderly underweight anorectic patients had significantly lower levels of beta-endorphin but increased concentrations of NPY in both plasma and CSF when compared to controls. In addition to significantly higher levels of CCK8s but not CCK33 in plasma, we found a trend to higher CSF concentrations of CCK8s and a positive correlation between the body mass index and either beta-endorphin (r = 0.58, P < 0.05) or CCK8s (r = 0.69, P < 0.01) concentrations in CSF in the anorectic group. CSF somatostatin concentrations were decreased significantly, but plasma somatostatin levels and plasma and CSF concentrations of CGRP were similar in senile anorectics and controls. Treatment of five anorectic patients with megestrol acetate, 480 mg daily for 6 months, reversed only the decrease in CSF beta-endorphin levels but did not normalize the body weight or the fat body mass. On the basis of our findings, we hypothesize that a decrease in CSF beta-endorphin concentration along with a rise in plasma levels of CCK8s might be accounted for the primary anorexia of aging.

Aged↗

Making sense of hypothyroidism. An approach to testing and treatment.

Development of the newer, sensitive assay for thyrotropin (thyroid-stimulating hormone [TSH]) has simplified the diagnosis and management of hypothyroidism. Serum free thyroxine (T4) levels measured by analogue techniques or free T4 index may be used in conjunction with TSH test results to confirm the diagnosis. Treatment consists of daily doses of levothyroxine sodium (Levothroid, Levoxine, Synthroid), which are increased slowly to achieve an optimal dose. Close monitoring with TSH assay is important to ensure adequate treatment. In euthyroid sick syndrome, results of thyroid function tests are abnormal in patients with nonthyroidal illness; treatment is indicated if symptoms of hypothyroidism are present. Patients with subclinical hypothyroidism also may benefit from treatment.

Euthyroid Sick Syndromes↗

Cysticercosis as a major cause of epilepsy in Peru. The Cysticercosis Working Group in Peru (CWG)

In countries where cysticercosis is endemic, the proportion of epilepsy due to cysticercosis is not well documented. To investigate the association between cysticercosis and epilepsy, we used the enzyme-linked immunoelectrotransfer blot (EITB) assay to detect serum antibodies to Taenia solium in 498 consecutive outpatients at a neurology clinic in Lima, Peru. Every patient was classified as epileptic (n = 189) or non-epileptic (n = 309) after neurological, and where possible electroencephalographic, examination. A substantially higher proportion of epileptic than non-epileptic patients was seropositive in the EITB (22 [12%] vs 8 [3%], p < 0.001). 19% of epileptic patients born outside Lima, 20% of those with late-onset epilepsy, and 29% of patients with both these characteristics were seropositive. Thus, in Peru, cysticercosis is an important aetiological factor for epilepsy.

Adolescent↗

Quantitative morphological changes in neurons and glia in the frontal lobe of the aging rat.

The quantitative morphological changes in neurons and glia during the aging process were analyzed in the different cortical layers, grouped as I, II-IV, V, and VI, of the frontal cortex of the rat. The parameters analyzed were cortical volume, neuronal density, glial density, and neuronal soma and nucleus areas. No changes with age were found in the volume of the layers, in neuronal density (with the exception of layer I), or in the area of the neuronal soma. However, older animals showed a 10 to 20% increase in glial density, depending on the layer studied. In addition, there was an age-related decrease in the area of the neuronal nucleus in layers II-IV, V, and VI. These results support the idea that the aging frontal cortex undergoes structural changes that may be involved in the morphological basis of memory and cognitive impairments characteristic of aging.

Aging↗

Is a single mutation at the same locus responsible for all affected cases in a large Alzheimer pedigree (FAD4)?

Analysis of marker segregation in the large Alzheimer pedigree, FAD4, leads to the conclusion, with a type I error of 5%, of linkage heterogeneity between two branches of the pedigree: the disease cosegregates with chromosome 21 markers flanking the APP area in one branch and not in the other one. Thus, we conclude that a single mutation in the chromosome 21 region surrounding APP cannot be responsible for all the affected cases in this pedigree.

Alleles↗