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Biomedical subjects

C Ruiz

Publications and source records attributed to C Ruiz.

At least 109 records · Page 6Linked to original sources
PubMed1993

An image analyzer study of central serous chorioretinopathy.

The angiographic characteristics of central serous chorioretinopathy (CSC) were studied by analyzing digitalized angiograms with an IMAGEnet system. We determined the type of leak, its location, and its distance from the fovea and from the center of the detachment. Round leaks were located farther from the detachment center and farther from the fovea than smokestack leaks. Detachments tended to center on the fovea regardless of the leak to fovea distance. These findings suggest that for serous detachment of the sensory retina to develop and be maintained, there must be a diffuse dysfunctional area of retinal pigment epithelium and a focal leak.

Adult↗
PubMed1993

Application of flow cytometry to the study of antiphagocytic properties of Klebsiella pneumoniae capsular polysaccharide.

We used flow cytometry to compare the effects of whole cells and capsular polysaccharides of Klebsiella pneumoniae on the phagocytic ability ot polymorphonuclear leukocytes. Our results showed a light decrease in phagocytic activity in the presence of capsular polysaccharides, but a marked decrease with whole cells. Our findings suggest that the resistance to phagocytosis in these microorganisms is not due exclusively to their capsule, as claimed by other authors.

Flow Cytometry↗
PubMed1993

Comparison of the proportions of leukocytes in early and term human decidua.

The percentages of cells expressing immune markers were determined with immunohistochemistry and flow cytometry in early and term human decidua. Although we found no variation in the proportion of cells of bone marrow origin (CD45+), the percentages of T cells and CD16+ lymphocytes were significantly higher in term decidua. On the contrary, CD56+ lymphocytes, the most abundant leukocyte type in early decidua, decreased at term. These variations may reflex the immunological adaptations of decidua during pregnancy.

Antigens, CD↗
PubMed1993

Puffs and PCR: the in vivo dynamics of early gene expression during ecdysone responses in Drosophila.

The steroid hormone ecdysone orchestrates insect development by regulating gene networks. In Drosophila the most detailed description of ecdysone action is the sequential activation of early and late puffs in the polytene chromosomes of the late larval salivary gland. A number of these early puffs (2B5, 74EF and 75B) contain complex transcription units (Broad-Complex, E74 and E75 respectively) encoding families of regulatory proteins which are expressed in most if not all tissues. In vitro, transcripts of the different isoforms of these early genes as well as the ecdysone receptor (EcR) present varying dose response characteristics (Karim and Thummel, 1992, EMBO J. 11, 4083-4093). We have developed an in vivo approach using a reverse transcription-polymerase chain reaction assay (RT-PCR) so as to visualise these transcripts in the RNA extracted from a single salivary gland. Using one salivary gland lobe for developmental puff staging and the sister lobe for RT-PCR, we have obtained precise developmental profiles for these transcripts and have extended our study to other tissues and stages where puffing studies were not possible. In the salivary gland we have characterised three distinct ecdysone responses. For the mid and late third larval instar responses our results confirm and extend the conclusions of the in vitro studies concerning the temporal expression of the early gene isoforms. The relatively brief prepupal response contains elements in common with each of the larval responses and all three can be explained by the profiles of the respective ecdysone peaks. Interestingly EcR transcripts respond differently during each response. The analysis of different tissues of the same animal reveals subtle differences in the timing of the ecdysone response and isoform expression and suggests that this may reflect tissue differences in the ecdysone profiles. As these molecules have homologues in vertebrates, our analysis may have general implications for the organisation of hormonal responses in vivo.

Animals↗
PubMed1992

Transseptal catheterization update 1992.

Resurgence of the transseptal procedure in the last decade has occurred coincident with the advent of therapeutic catheterizations and in particular mitral balloon vavuloplasty. As larger numbers of these procedures have been performed, experience shows that the position of intended septal puncture varies for each anticipated procedure and need not lie at the fossa ovalis, which is frequently displaced or inaccessible. Recognizing the dynamic alterations in septal and atrial anatomy that accompany the various combinations of valvular heart disease, the experienced interventionalist will use precatheterization echo and radiological techniques to enable precise and localized transseptal puncture. Using these techniques in 597 patients for valvular heart disease, we have had no deaths and a morbidity of 1.8% with the transseptal puncture.

Cardiac Catheterization↗
PubMed1992

Insect immunity: developmental and inducible activity of the Drosophila diptericin promoter.

Diptericins are 9 kDa inducible antibacterial peptides initially isolated from immune haemolymph of Phormia (Diptera). Following the isolation of a Drosophila cDNA encoding a diptericin homologue, we have now cloned a genomic fragment containing the Drosophila diptericin gene. To dissect the regulation of this gene, we have transformed flies with a fusion gene in which the reporter beta-galactosidase gene is under the control of 2.2 kb upstream sequences of the diptericin gene. We show that such a fusion gene is inducible by injection of live bacteria or complete Freund's adjuvant and respects the tissue specific expression pattern of the resident diptericin gene. Our analysis reveals at least four distinct phases in the regulation of this gene: young larvae, late third instar larvae, pupae and adults. This complexity may be related to the presence in the upstream sequences of multiple copies of response elements previously characterized in genes encoding acute phase response proteins in mammals (e.g. NK-kappa B, NF-kappa B related, NF-IL6 response elements).

Acute-Phase Proteins↗
PubMed1992

Unsuspected rheumatic heart underlying group B streptococcal endocarditis at the age of 20 months.

The case is reported of a 20-month-old girl admitted to our centre for group B streptococcal endocarditis who died of complete atrioventricular block after a week of treatment. There was no history pointing to the presence of a heart disorder. Necropsy disclosed the surprising existence of a vast rheumatic carditis involving essentially the aortic and mitral valves, with bacterial superinfection of the former. The double rheumatic and infectious lesion in such a young patient with infective pseudo-aneurysms of the sinuses of Valsalva makes this an exceptional case.

Aortic Aneurysm, Thoracic↗
PubMed1992

Treatment of thymomas. A report of 67 cases.

From 1979 to 1989, 126 patients were treated for thymic tumors. Of these, 67 (53%) had thymomas occurring in 27 men and 40 women; the mean age was 46 years: 24 patients had no symptoms and myasthenia gravis was present in 21 cases. A complete resection was performed in 45 patients, associated in 22 with postoperative adjuvant treatment (radiotherapy, 2; radio- and chemotherapy, 20). Two patients had a partial resection followed by radiotherapy and chemotherapy. Twenty patients had initially only a biopsy and were treated by irradiation in 3 cases, radio- plus chemotherapy in 16, radio- plus chemotherapy and subsequent resection in 1 case. The staging was carried out according to the GETT Classification (stage I A:26; I B:6; II:12; III A:1; III B:18; IVA:4). Thymomas were found to be of predominant epithelial type in 12 cases, predominantly lymphocytic type in 9, and mixed in 46. No recurrence occurred after complete resection. The overall 10-year survival was 71.1%. A good correlation was found according to staging: 96% in stage I; 80% in stage II; 35% in stage III. Presence of myasthenia gravis did not affect the results. The best prognostic factor remains complete resection with postoperative radiotherapy to prevent recurrences. The role of adjuvant chemotherapy needs further evaluation.

Adolescent↗
PubMed1992

Cardiovascular reflexes in patients with vascular headache.

We have investigated the autonomic function of 75 patients with migraine by examining cardiovascular reflex function. The results were compared with those of 78 healthy volunteers. Measurements were made between attacks. Patients with migraine showed a smaller heart-rate response to deep breathing but a greater heart-rate response and higher blood pressure to standing when compared to controls. Migraine patients had a higher percentage of established sympathetic lesions (51% vs 17%) and severe (25% vs 5%) or atypical (24% vs 11.5%) global autonomic dysfunction. No significant differences were found among patients with migraine with aura, migraine without aura, and migraine with prolonged aura. Our findings indicate that patients with migraine have sympathetic hypofunction.

Adolescent↗
PubMed1992

Epidemic dermatitis due to contact with a moth in Cozumel, Mexico.

In early December 1989, an outbreak that was initially thought to be scabies was investigated among employees of tourist hotels in Cozumel, Mexico. Of 417 employees interviewed, only 19 (4.6%) met a case definition for scabies dermatitis, while 91 (21.8%) reported a nonspecific dermatitis of less than one-week's duration. Persons with nonspecific dermatitis related the onset of their dermatitis to skin contact with a moth that had been present in large numbers in November. At the time of the initial investigation in December, there were no active cases of dermatitis and the moth was no longer present. During early January 1990, numerous cases of dermatitis again began to be reported. Using a case definition for nonspecific dermatitis, a survey of Cozumel's resident population showed an attack rate of 12.1%. A case-control study revealed the only significant risk factor to be skin contact with the suspect moth (P less than 0.01), which had returned in large numbers. Six health workers volunteered to have the moth rubbed on their skin; within 5 min, five of six developed an intense pruritus followed by an erythematous rash. The moth was classified as Hylesia alinda Druce. This species has nettling hairs on its abdomen that excrete a histamine-like substance. Although this moth is normally present in small numbers in Cozumel, the passage of hurricane Gilbert killed most of its natural predators (wasps and bees), allowing its population to overgrow. No control measures were undertaken because the moth's natural predators returned that spring and dramatically reduced the moth population. No further outbreaks of dermatitis occurred.

Adolescent↗
PubMed1991

Response of brain protein kinase C isozymes to ethyl oleate, an alcohol metabolite.

Rat brain protein kinase C (PKC) isozymes I, II and III were stimulated by fatty acids in the absence and presence of calcium. Ethyl oleate, which by itself has no effect on PKC activity, had a potentiating effect on fatty acid-induced activation of all 3 isozymes. Potentiation was observed predominantly in the presence of calcium. Interaction of ethyl oleate with a signalling mechanism involving PKC may underlie the cognitive disturbances noted after alcohol consumption.

Animals↗
PubMed1991

Dose dependent inhibition of REM sleep in normal volunteers by biperiden, a muscarinic antagonist.

We tested the effect of biperiden (2, 4, and 8 mg per os 30 min before bedtime) on the polygraphically recorded sleep of normal volunteers (n = 8). Biperiden is a cholinergic, muscarinic receptor antagonist that may preferentially block the M1 receptor subtype. Compared with placebo, biperiden significantly prolonged rapid eye movement (REM) latency and suppressed REM sleep time and REM percentage in a dose-dependent manner. These REM suppressing effects of biperiden are similar to those previously reported with scopolamine and other nonselective muscarinic receptor antagonists. Because of uncertainties about the pharmacological specificity of biperiden, further studies are needed to determine the mechanism of action and the role of M1 receptors subtypes in the regulation of REM sleep.

Adult↗
PubMed1991

The effects of scopolamine on sleep and mood in depressed patients with a history of alcoholism and a normal comparison group.

In order to determine the effect of an anticholinergic agent on mood and sleep, scopolamine (0.4 mg IM) was administered before bedtime for three consecutive nights to 10 depressed patients (8 with a history of alcohol abuse) and 10 normal comparison subjects. The patients had a small, statistically significant antidepressant response on the second morning of treatment. Scopolamine inhibited rapid eye movement (REM) sleep and prolonged REM latency equally in depressed patients and the normal comparison group. Partial tolerance to the REM inhibiting effect of scopolamine developed between the first and third night of treatment. A REM rebound occurred during recovery nights. These results are consistent with concepts relating central cholinergic mechanisms to the control of REM sleep. Compared with controls, patients showed a greater increase in Stage 2 and Stage 2% and a lesser and increase in Delta (Stage 3 and 4) sleep % and Stage 4% on the first night of treatment. Further, well-controlled studies are needed to determine whether anticholinergic drugs possess clinically significant antidepressant effects.

Adult↗
PubMed1991

The cholinergic rapid eye movement induction test with arecoline in depression.

The cholinergic rapid eye movement (REM) induction test using arecoline hydrobromide, a cholinergic muscarinic receptor agonist, was studied in patients with affective disorder and in normal controls to determine whether or not depression is associated with enhanced induction of REM sleep by muscarinic agonists. Arecoline induced REM sleep in a dose-dependent fashion in both patients and controls compared with placebo infusions. Compared with normal controls, patients entered REM sleep significantly more rapidly following intravenous administration of 1.0 mg of arecoline hydrobromide than they did following administration of 0.5 mg of arecoline hydrobromide or placebo. These results, as well as those of previous studies, support the hypothesis that patients with affective disorder show a functional supersensitive induction of REM sleep in response to muscarinic receptor agonists and may be consistent with the hypothesis that functional muscarinic receptor "up regulation" is associated with depression.

Arecoline↗
PubMed1991

Extramedullary nasal plasmacytoma.

The literature on this rare tumour has been reviewed and three cases of nasal plasmacytoma are described. Immunohistochemistry demonstrated cytoplasmic IgA and Kappa determinants in all cases. Two patients are disease-free at the present time, the third developed an IgG-k multiple myeloma, previously not described in the literature.

Aged↗
PubMed1991

[Cancer incidence by municipalities in Puerto Rico].

This study consist of the trends of those malignant tumours in Puerto Rico diagnosed 1960 to 1988 that we considered more related with some environmental factors. For this purpose 160,288 cancer cases analyzed included 16,286 of squamous and basal cell carcinomas of the skin diagnosed from 1950 up to 1975 only. We have darkened in the map and mentioned below in this summary those municipalities with incidence greater than Puerto Rico's average.

Cohort Studies↗
PubMed1990

Hodgkin's disease in patients with antibodies to human immunodeficiency virus. A study of 22 patients.

The experience of 22 Hodgkin's disease (HD) patients with human immunodeficiency virus type I (HIV) antibodies, collected from a cooperative study of six hospitals during 1984-1989 is presented. Young men (average age, 27.6 years) with a high incidence of intravenous drug abuse (86%) were found. The status of the HIV infection at diagnosis of HD was: four patients, acquired immune deficiency syndrome (AIDS); eight patients, persistent generalized lymphadenopathy (PGL); and ten patients, asymptomatic. The natural history of HD was unusual, with a high incidence of B symptoms (81%), advanced Stages III to IV (90%), bone marrow invasion (50%), cytopenias before treatment (45%), opportunistic infections (68%), and aggressive histologies. A decreased response to chemotherapy with poor marrow tolerance and a significant decrease in survival, 18 months, was observed. The AIDS and cytopenias pretreatment were associated with a shorter statistically significant survival, which defines the importance of immunodeficiency in HD prognosis. Complete remission after treatment was a factor that contributed to a longer statistically significant survival. The PGL or asymptomatic patients survived longer but also had a poor course, and five of them had AIDS criteria during evolution. A high incidence of HD in relation to non-Hodgkin's lymphoma (NHL) in patients with HIV infection in the six cooperating hospitals was found. Criteria for considering HD as an AIDS-associated lymphoproliferative disease in our environment are discussed.

Acquired Immunodeficiency Syndrome↗