Search PubMed⌕ Search

Biomedical subjects

M Cruz

Publications and source records attributed to M Cruz.

At least 73 records · Page 4Linked to original sources
PubMed1996

Proposal of diagnostic criteria for human cysticercosis and neurocysticercosis.

Taenia solium cysticercosis is a major public health problem in several areas of the world. While the disease has a recognized etiologic agent, its definitive histological diagnosis is not possible in most cases because this parasite tends to lodge in cerebral tissues where routine biopsy is not feasible. Therefore, the diagnosis of human cysticercosis (and neurocysticercosis) should rest on the proper interpretation of the patients' symptoms together with data provided by radiological studies and immunologic tests for the detection of anticysticercal antibodies. Unfortunately, the pleomorphism of this parasitic disease creates confusion when non-specific clinical, radiological, or immunologic criteria alone are used to detect cases among populations or to diagnose hospitalized patients with neurological manifestations. We propose a chart of diagnostic criteria for human cysticercosis that objectively permit clinicians and health care workers to evaluate clinical, radiological, immunologic, and epidemiologic data of patients. The chart uses four degrees of criteria: absolute, major, minor, and epidemiologic, that were selected on the basis of their individual diagnostic strength. Interpretation of such criteria will result in three categories of diagnostic certainty: definitive, probable and possible, according to the likelihood that cysticercosis is present in a given person.

Cysticercosis↗
PubMed1996

Intramedullary spinal cord metastasis: report of three cases and review of the literature.

BACKGROUND: Intramedullary spinal cord metastasis is rare; but it is being encountered with increasing frequency. Optimal treatment after diagnosis remains controversial. METHODS: In the last 3 years, we have encountered three cases of intramedullary metastasis presenting as focal mass lesions with minimal systemic evidence of cancer. We present our results in these patients and review the literature in an effort to more optimally define both the natural course of this disease, as well as a potential subset of patients who might benefit from more aggressive treatment. RESULTS: With the availability of more sensitive imaging techniques, these tumors are being diagnosed with increasing frequency. Magnetic resonance imaging is sensitive, but nonspecific, in distinguishing intramedullary spinal cord metastases from primary cord tumors. Urgent biopsy is often necessary prior to definitive treatment. Radiation with chemotherapy significantly prolongs survival. Radical subtotal resection may offer additional quality survival, especially in cases of metastatic melanoma with an occult primary. CONCLUSIONS: Regardless of treatment, many patients survive less than 1 year. Intramedullary spinal cord metastasis is a devastating condition, but with appropriate diagnosis and aggressive treatment, selected patients may have substantially increased survival.

Breast Neoplasms↗
PubMed1996

Cryptic speciation in Lutzomyia (Nyssomyia) trapidoi (Fairchild & Hertig) (Diptera: Psychodidae) detected by multilocus enzyme electrophoresis.

Lutzomyia trapidoi is the major vector of cutaneous leishmaniasis in Ecuador. In the framework of an epidemiologic study, female Lu. trapidoi sand flies were captured on human bait in La Tablada and Paraiso Escondido. Some coloration heterogeneity among the specimens caught led us to look for the existence of cryptic species using multilocus enzyme electrophoresis. In 196 specimens studied, five of seven enzyme loci proved to be variable, making it possible to check for departures from panmixia both by Hardy-Weinberg statistics and linkage disequilibrium analysis. Two discrete groups were clearly distinguished, which could be differentiated by the diagnostic locus glycerophosphate dehydrogenase. The two groups occurred in sympatry within each locality. Genetic distances measured between these two groups were consistent with values usually found between distinct species. These results suggest the existence of a least two sibling species in Paraiso Escondido as well as La Tablada. The epidemiologic relevance of these results is discussed.

Animals↗
PubMed1996

Influence of the pituitary gland on the immune response in young rats.

The response of hypophysectomized (HYPOX) and sham-operated (S-HYPOX) female and male Wistar young rats (8 weeks old) to antigenic stimulation was compared. Humoral antigenic responses against hemocyanin were measured by ELISA. [3H]thymidine incorporation into cultured spleen cells was used to determine proliferative response to concanavalin A (ConA) or antigenic stimulation. Anti-hemocyanin serum titers in the HYPOX animals was about half of that observed in control S-HYPOX rats. Similarly, the cellular proliferative response was significantly decreased in HYPOX animals when compared to S-HYPOX rats; the blastogenic response to hemocyanin in UC rats (which did not receive the antigen injection) was close to zero. S-HYPOX control rats responded to direct ConA stimulation as UC controls. Body weight and the weight of pituitary target organs (adrenal, thyroid, ovary and testes) was about 1/4 of that of controls. Hypophysectomy also resulted in a striking reduction in spleen weight. These results indicate that the pituitary gland is involved in cellular and humoral immune regulation in young rats.

Animals↗
PubMed1995

Acute otitis media in childhood: a study of 20,532 cases.

We present a study of acute otitis media among 20,532 Spanish children during a 6-month period from January through June 1991. The study was done by distributing a questionnaire to all Spanish pediatricians. Of the patients 51.7% were girls and 48.3% boys; 68.7% of all children were younger than 5 years. The most frequent symptoms were otalgia or irritability, 92.7%; fever, 63.5%; otorrhea, 24.9%; vomiting, 21.4%; and another concomitant upper respiratory tract infection, 65.5%. Otitis was bilateral in 45.6% of the cases. The most frequently used antibiotic was cefixime (38%), followed by amoxicillin-clavulanate (22.2%), amoxicillin (15.3%), 2nd-generation cephalosporins (13.5%) and macrolides (8.8%). In 11.8% of the patients, a change in the initial antibiotic therapy was required due to adverse effects. Resolution of symptoms occurred in 77.8% of the patients.

Acute Disease↗
PubMed1995

Antimalarial activity of oxidized starch and cellulose imine derivatives.

With the purpose of screening potential antimalarial agents, oxidized starch imine derivatives of sulfonamides or pyrimidine - derivatives of sulfisoxazole (ML8), sulfameter (ML11) and trimethoprim (ML13) - and oxidized cellulose imine derivatives of dapsone (ML14), sulfadiazine (ML17), sulfamethoxazole (ML18), sulfisoxazole (ML19), sulfamethoxypyridazine (ML20) and sulfameter (ML22) were submitted to in vivo biological assays with mice infected with Plasmodium berghei. Only ML11 was 100% curative in test conditions; ML 17 showed the same effect as its prototype. The drug content in both prodrugs is lower in the applied dose than that used in the original drugs. It can be suggested that the latentiation enhanced the effectiveness of the prototypes.

Animals↗
PubMed1993

Ecdysteroid regulation of olfactory protein expression in the developing antenna of the tobacco hawk moth, Manduca sexta.

During adult metamorphosis, the moth olfactory neurons and their glia-like support cells pass through a coordinated and synchronous development. By 60% of development, the olfactory system is anatomically complete, but functional maturation does not occur until about 90% of development. Maturation is characterized by the onset of odorant sensitivity in the sensory neurons and the expression of certain antennal-specific proteins including odorant binding proteins (OBPs) and odorant degrading enzymes (ODEs). The OBPs have been cloned and sequenced, and are thus useful models for investigating the molecular mechanisms coordinating final maturation of the developing olfactory system. The ecdysteroid hormones have been observed to regulate many cellular level neuronal changes during adult metamorphosis. In particular, the late pupal decline in ecdysteroids is known to influence programmed death of nerves and muscles at the end of metamorphosis. Experiments are presented here which indicate that this decline in ecdysteroids also induces the expression of the OBPs. Normal OBP expression occurs 35-40 h before adult emergence. In culture, OBP expression could be induced at least 90 h before adult emergence by the premature removal of ecdysteroid. This premature expression was blocked by culturing tissue in the presence of the biologically active ecdysteroid 20-hydroxyecdysone. These findings suggest that maturation of the olfactory system is regulated by the decline in ecdysteroids, and support the view that olfactory development, in general, may be coordinated by changing levels of pupal ecdysteroids.

Aldehyde Oxidase↗
PubMed1993

Clinical, neurophysiological and immunological evidence of polyneuropathy in patients with monoclonal gammopathies.

In this study we estimated the prevalence of polyneuropathy (PN) in patients with monoclonal gammopathies. 31 patients with monoclonal gammopathies (19 with monoclonal gammopathy of uncertain significance (MGUS), 10 with multiple myeloma (MM), and 2 with Waldenström's macroglobulinemia), were studied by clinical and neurophysiological examination, blood tests to exclude other causes of PN, ELISA assays to detect antibodies to peripheral nerve myelin (PNM), and antibodies to myelin associated glycoprotein (MAG). 11 of 31 patients (36%) had a clinical PN, 3 (10%) had a probable PN (signs but no symptoms), and 4 (13%) had a subclinical PN (only neurophysiological signs of PN). Thus, in total 18 patients (58%) had some form of PN, in contrast to an age-matched control group (n = 33) where only 2 persons (6%) had some form of PN; 1 had a probable PN and 1 had a subclinical PN. 3 patients had anti-PNM and anti-MAG antibodies of IgM isotype, all 3 patients showing a demyelinating PN. The remaining patients with PN had a mild or moderate distal PN. One patient had a myelopathy and 1 had amyotrophic lateral sclerosis (ALS). IgM isotype of the M-protein was associated with a high risk of clinical PN (5 out of 6 (83%)), in contrast to IgG (5 out of 18 (28%)) and IgA (1 out of 6 (17%)). We conclude that PN is a common finding in patients with monoclonal gammopathies, but only some of them are of the demyelinating type and associated with antibodies to PNM or MAG.

Adult↗
PubMed1993

Susceptibility to demyelinating polyneuropathy in plasma cell dyscrasia may be influenced by amino acid position 9 of the HLA-DR beta chain.

Fifty-five patients with plasma cell dyscrasias were investigated by genomic typing for HLA-DR and -DQ genes by restriction fragment length polymorphism, neurophysiology and for presence of anti-myelin-associated glycoprotein (MAG) antibodies. In 26 patients, a polyneuropathy (PN) of demyelinating type was established. Among these individuals, an association was found with the presence of a tryptophan amino acid residue at position 9 of the DR beta chain (P < 0.01). This position is part of the first hypervariable region of the DR beta chain, and may be of importance in determining preferential peptide-binding capacity of the HLA-DR molecule. The presence of anti-MAG antibodies in 15 out of 17 patients with an IgM M-component and demyelinating PN (14 of these 15 individuals carrying a tryptophan at position 9) supports the pathogenic role of an autoimmune response against MAG. The finding of an HLA class II association may indicate a pathogenic role of T cell immunity in this condition.

Adult↗
PubMed1993

Efficacy of intravenously administered theophylline in children hospitalized with severe asthma.

PURPOSE: To determine whether intravenously administered theophylline, when added to frequently nebulized albuterol and intravenously administered methylprednisolone, benefits children hospitalized with severe asthma. DESIGN: Prospective, randomized, placebo-controlled, parallel-group, double-blind study. SETTING: Inpatient pediatric service at a tertiary-care teaching hospital. PATIENTS: Twenty-one children 5 to 18 years of age. INTERVENTIONS: All patients received 2.5 to 5.0 mg of nebulized albuterol every 20 minutes to every 6 hours, intravenously administered methylprednisolone (1 mg/kg every 6 hours), and either intravenously administered theophylline (as aminophylline) or placebo for 36 hours. Serum theophylline concentrations were maintained between 55 and 110 mumol/L (between 10 and 20 micrograms/ml) by adjusting loading doses and continuous infusion rates. MEASUREMENTS AND MAIN RESULTS: Forced expired volume in 1 second (FEV1) and clinical score were measured at 0, 1, 3, 6, 12, 24, and 36 hours after the start of each individual study. The total number of nebulizations, total albuterol dosage, adverse effects, and duration of hospital stay were recorded. Twelve children received theophylline and nine received placebo. The two groups did not differ significantly in age, sex, or baseline FEV1. In both groups, clinical score significantly improved from baseline by 12 hours, and FEV1 by 24 hours (p < 0.05). There were no significant differences between the groups in FEV1 or clinical score at any of the measured time points. There were no significant differences in rate of improvement in FEV1, total number of nebulizations, total albuterol dosage, or duration of hospital stay. Adverse effects were mild and infrequent and did not differ significantly between the two groups. CONCLUSIONS: Theophylline, at therapeutic concentrations, did not additionally benefit children hospitalized with severe asthma who were being treated frequently with nebulized albuterol and with methylprednisolone intravenously.

Administration, Inhalation↗
PubMed1993

Intrathecal synthesis of anti-Borrelia burgdorferi antibodies in neuroborreliosis: a study with special emphasis on oligoclonal IgM antibody bands.

Pre- and post-treatment (up to 3-26 months after antibiotic therapy) humoral immune responses were investigated in five neuroborreliosis patients. Anti-Borrelia (B.) burgdorferi IgG and IgM antibodies in CSF and serum were quantitated by capture ELISA. Agarose gel isoelectric focusing (AIF) and protein blotting were used to detect oligoclonal IgG and IgM bands as well as oligoclonal anti-B. burgdorferi IgG and IgM antibodies. These latter components were visualized by transfer to antigen-coated membranes (immunoblot) and immunoenzymatic staining. By ELISA, intrathecal anti-B. burgdorferi IgG and IgM antibody synthesis was detected in all initial specimens and continued 3-26 months after antibiotic therapy in four and three cases, respectively. AIF with protein blotting showed oligoclonal bands of total IgG as well as total IgM in the initial CSF specimens of all patients and persistence of such components occurred in four and five cases, respectively. By AIF and immunoblot, oligoclonal anti-B. burgdorferi IgG and IgM antibody bands could be detected in the CSF of every patient. IgG antibody bands were present in all initial CSF samples. The first specimen of one patient was negative for IgM antibody bands but such components appeared 3 weeks later. Oligoclonal CSF anti-B. burgdorferi IgG antibody components persisted over the entire follow-up periods in all but one case where they disappeared 6 weeks after treatment. The oligoclonal IgM antibodies in CSF vanished in two cases (after being present up to 4 and 11 months after antibiotic therapy) while they persisted over the entire (3-6 months after antibiotic therapy) follow-up periods in three cases. The specificity of the IgM antibody immunoblot technique was corroborated by control experiments, including antibody absorption studies and use of 41 kDa flagellar antigen.

Adult↗
PubMed1993

Vasopressin in cerebrospinal fluid of newborns with hypoxic-ischemic encephalopathy. Preliminary report.

Vasopressin in cerebrospinal fluid has been measured in 27 fullterm newborns with hypoxic-ischemic encephalopathy. These newborns were divided into three groups according to the degree of neurological involvement, and they have been compared with a control group of 10 newborns. Determinations of vasopressin in cerebrospinal fluid and plasma were done by RIA. The cerebrospinal fluid vasopressin in asphyxiated newborns was higher than in the control group (p < 0.001); the mean concentration in the group of newborns classified as moderate or severe hypoxic-ischemic encephalopathy was higher than in the control group (18.7 pg/ml vs 4.66 pg/ml), and also higher than in the group classified as mild (14.2 pg/ml). Cerebrospinal fluid vasopressin values have a direct relationship to the plasmatic values at 12 hours of life (r = 0.76; p < 0.001). We concluded that vasopressin values in cerebrospinal fluid at 12 hours increase according to the clinical severity of the neonatal hypoxic-ischemic encephalopathy and that they have a strong relationship with plasmatic vasopressin.

Asphyxia Neonatorum↗
PubMed1992

Immobilized pH gradient isoelectric focusing and immunoblotting for investigations of anti-Borrelia burgdorferi IgG antibodies.

Anti-Borrelia burgdorferi immunoglobulin G (IgG) responses in cerebrospinal fluid, serum, and joint fluid from Lyme disease patients were investigated by immobilized pH gradient (IPG) isoelectric focusing (IEF) in pH 4-10 and pH 4-7 gels. After focusing, the anti-B.-burgdorferi antibodies were blotted by affinity-driven transfer to antigen-coated polyvinylidene difluoride membranes (immunoblot) and the IgG antibodies were immunoenzymatically stained. IPG-IEF gels gave an excellent resolution of IgG and the immunoblot proved advantageous for the detection of anti-B. burgdorferi IgG antibodies. These antibodies, as judged from the electromigration characteristics, were found to contain oligoclonal as well as polyclonal subpopulations. This latter group included IgG antibodies that were inadequately resolved when separated by conventional carrier ampholyte IEF.

Antibodies, Bacterial↗
PubMed1992

Light chain distribution of anti-Borrelia burgdorferi IgG antibodies in Lyme arthritis.

Joint fluid (JF) and serum IgG from eight Lyme arthritis patients was investigated by isoelectric focusing, blotting to membranes of uncoated nitrocellulose (NC) as well as Borrelia (B.) burgdorferi antigen-coated NC (immunoblot) and immunoezymatic staining for visualization of the IgG isotype and characterization of the kappa/lambda light chain distribution. Oligoclonal bands of total IgG occurred in JF as well as in serum (3 cases) or in JF only (1 case); IgG lambda components were present in all four subjects and IgG kappa in three. IgG (Fc frag) reactive but kappa/lambda light chain negative oligoclonal bands were present in JF of one further patient. Additional investigations supported the interpretation that these components were free gamma chains. Oligoclonal anti-B. burgdorferi IgG antibodies occurred in JF as well as in serum (6 cases) or in JF only (1 case). There were complete identities, as defined by isoelectric points and light chain types, between JF and serum antibodies in an individual patient while identities between oligoclonal bands of total IgG and anti-B. burgdorferi IgG were infrequent. Antibodies of IgG kappa identity were present in all seven patients and six of them also had IgG lambda antibodies. The antibody response was, therefore, by definition oligo- and not monoclonal in 6 out of 7 patients. Furthermore, the anti-B. burgdorferi antibodies of IgG kappa identity only that were present in one case did not exhibit any completely characteristic monoclonal microheterogeneity.

Adolescent↗
PubMed1991

Antibodies to myelin-associated glycoprotein are found in cerebrospinal fluid in polyneuropathy associated with monoclonal serum IgM.

Antibodies to myelin-associated glycoprotein (MAG) have been demonstrated in the serum samples from about half the patients with polyneuropathy associated with serum IgM monoclonal component. We examined cerebrospinal fluid (CSF) and serum samples from 13 patients with this disease by enzyme-linked immunosorbent assay for anti-MAG IgM antibodies. We detected these antibodies in both CSF and serum samples in 10 of the patients; in three of them the antibodies were at higher levels in the CSF. The remaining three patients had anti-MAG IgM antibodies in the CSF only. Intrathecal production of anti-MAG IgM antibodies is thus common in polyneuropathy associated with IgM monoclonal component. In three patients, examined on two occasions from 1 to 7 years, high anti-MAG IgM antibody levels persisted in CSF and serum samples. Among 165 patients with other neurologic diseases, including 60 with multiple sclerosis and 60 control subjects with tension headache, anti-MAG IgM antibodies were detected in the CSF from three patients (two with multiple sclerosis, one with aseptic meningitis), and in the serum sample of one patient with multiple sclerosis. Whether the frequent occurrence of anti-MAG IgM antibodies in CSF and their intrathecal synthesis has pathogenetic relevance for the development of polyneuropathy associated with IgM monoclonal component is unsure.

Aged↗
PubMed1991

Cells secreting anti-MAG antibody occur in cerebrospinal fluid and bone marrow in patients with polyneuropathy associated with M component.

Occurrence and distribution of cells secreting antibodies against myelin associated glycoprotein (MAG) were studied in 9 patients with polyneuropathy associated with the monoclonal (M) component in serum. Utilizing an immunospot assay, we found that 4 of 7 patients with polyneuropathy associated with an IgM M component had cells secreting anti-MAG IgM antibody in cerebrospinal fluid (CSF) numbering between 1 per 212 and 1 per 3333 mononuclear cells. All 7 patients had cells secreting anti-MAG IgM antibody in bone marrow (median value 1 per 2000 cells). In contrast, peripheral blood from only 2 of these patients contained low numbers of such cells. One patient with polyneuropathy associated with an IgA M component had cells secreting anti-MAG IgA antibody in CSF, and 1 with an IgG M component had cells secreting anti-MAG IgG antibody in CSF; both patients also had anti-MAG IgM antibodies detectable in CSF only by ELISA. These 2 patients may thus have concurrent intrathecal production of antibodies of 2 different isotypes which are directed against the same or different epitopes of MAG. The production of antibodies directed against a component of myelin occurring in the immediate vicinity of the peripheral nervous system might be involved in the pathogenesis of the polyneuropathy.

Adult↗