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Biomedical subjects

R Ramos

Publications and source records attributed to R Ramos.

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

Immediate postplacental insertion of GYNE-T 380 and GYNE-T 380 postpartum intrauterine contraceptive devices: randomized study.

OBJECTIVE: The purpose of the investigation was to compare the 1-year expulsion and efficacy rates of the GYNE-T 380 and the GYNE-T 380 Postpartum intrauterine contraceptive devices when inserted within 10 minutes after expulsion of the placenta in a term pregnancy. The two intrauterine contraceptive devices were identical, except that one was inserted by means of a temporary fundal suspension system and the other was placed directly into the uterine cavity. STUDY DESIGN: The study was a multicenter, randomized trial of intrauterine contraceptive devices in which 300 subjects accepted the GYNE-T 380 IUD and 292 subjects the GYNE-T 380 Postpartum IUD in clinics with adequate follow-up. RESULTS: At 1 year the gross cumulative expulsion rate was 13.2 per 100 cases (39 expulsions) with the GYNE-T 380 intrauterine contraceptive device and 16.2 per 100 cases (46 expulsions) with the GYNE-T 380 Postpartum device. There was no significant difference in the rate of expulsion between the two devices at any time during the year. There was one first-year intrauterine pregnancy, which occurred in a subject using the GYNE-T 380 device. The continuation rate for each device was above 80 per 100. CONCLUSION: The results indicate that both the GYNE-T 380 Postpartum and the standard GYNE-T 380 intrauterine contraceptive devices are safe and effective when inserted immediately after delivery of the placenta.

Female↗
PubMed1996

Outcome predictors of ultrafiltration in patients with refractory congestive heart failure and renal failure.

This study is an attempt to identify predictors of outcome from the use of ultrafiltration (UF) in patients with refractory congestive heart failure (CHF) and renal failure. The authors studied 30 patients in NYHA functional class IV in whom UF was utilized in the management of refractory CHF. Patients were retrospectively divided into two groups according to their outcome. Group A included 12 patients who improved and survived hospital admission, and group B included 18 patients who did not respond and died shortly after UF. Clinical, hemodynamic, and laboratory data before UF were fairly comparable between both groups. Renal function and hemodynamic parameters were compared and analyzed within the same group and between both groups before and after UF. The mean age in group A was sixty-three +/- thirteen years while in group B it was seventy +/- eleven years (P < 0.005). A mean of 9.6 liters of fluid were removed from group A and 3.2 liters from group B (P < 0.001). Group A showed greater reduction in the mean values of right atrial pressure (P < 0.005) and pulmonary capillary wedge pressure (P < 0.05) after UF. Additionally, group A showed a significant decrease in their blood urea nitrogen (P < 0.05) and serum creatinine values (P < 0.05), in contradistinction to group B patients who showed a major increase in those values after UF. There was no significant change in the mean values of cardiac index, systemic vascular resistance, and pulmonary vascular resistance after UF. These findings suggest that younger age groups, greater fluid removal, as well as significant decreases in blood urea nitrogen, serum creatinine, and right atrial and pulmonary wedge pressures after UF, are associated with favorable outcome. Conversely, older age groups, less fluid removal, and rising blood urea nitrogen and serum creatinine levels after UF were associated with poor outcome.

Age Factors↗
PubMed1996

A Xenopus nodal-related gene that acts in synergy with noggin to induce complete secondary axis and notochord formation.

Using a paracrine assay to screen for signaling proteins that could respecify ectodermal tissue, we isolated a Xenopus gene related to the mouse gene nodal, a member of the TGFbeta superfamily. The gene is expressed in three regions in the early Xenopus embryo: first in the gastrula organizer, then in two stripes of cells flanking the posterior notochord in late neurulae, and finally in lateral plate mesoderm restricted to the left side of tailbud-stage embryos. Ectopic expression of the gene induces muscle formation in ectodermal explants and partial secondary axes in whole embryos. Together with noggin, another secreted protein also present in the organizer, it induces notochord formation in ectodermal explants and complete secondary axes in whole embryos. These results suggest that the nodal-related gene may act together with noggin to induce axial pattern during gastrulation and also may play a role in left-right asymmetry generation in the post-gastrula embryo.

Animals↗
PubMed1996

The efficacy of pneumatic compression stockings in the prevention of pulmonary embolism after cardiac surgery.

INTRODUCTION: Pneumatic compression stocking (PCS) devices have been introduced to decrease the incidence of postoperative deep venous thrombosis (DVT). However, their role in the prophylaxis against pulmonary embolism (PE) remains unclear. This study was undertaken to compare the prophylactic effectiveness of subcutaneous heparin (SCH) alone vs the combined use of PCS and SCH in the prevention of PE following cardiac surgery. METHODS: We studied 2,551 consecutive patients who underwent cardiac surgery over a 10-year period. They were randomly allocated to two groups. Group A included 1,196 patients who were treated with 5,000 U of SCH every 12 h and group B included 1,355 patients treated with a combined prophylactic regimen of PCS and SCH. RESULTS: The diagnosis of PE was established in 69 patients by either high-probability ventilation perfusion scan, pulmonary angiogram, or autopsy. The incidence of PE in group A patients was 4% (48/1,196) and in group B was 1.5% (21/1,355). The concomitant use of bilateral PCS and SCH reduced the frequency of postoperative PE in 62% in comparison to the prophylaxis with SCH alone (p < 0.001). CONCLUSIONS: These data suggest that the combined prophylactic method of bilateral PCS and SCH is superior to SCH alone in the prevention of PE after cardiac surgery.

Aged↗
PubMed1996

CT findings after laparoscopic pelvic lymph node dissection and transperineal radioactive seed implantation for prostatic carcinoma.

OBJECTIVE: The purpose of this paper is to describe the CT findings in patients undergoing transperineal sonographically guided radioactive seed implantation with and without laparoscopic lymph node dissection for treatment of carcinoma of the prostate gland. MATERIALS AND METHODS: Ninety-six CT scans of the pelvis were retrospectively reviewed in patients who had undergone radioactive seed implantation of the prostate gland. The CT readings were correlated with the type of procedure each patient had and the pathologic results of laparoscopic lymph node dissection. RESULTS: Of 73 patients who underwent laparoscopic lymph node dissection, 42 were found at CT to have low-attenuation masses along lymph node chains. These masses resembled necrotic nodes. Only one patient who did not undergo laparoscopic lymph node dissection had similar findings. Fourteen patients had fluid collections within the pelvis, 13 of whom had undergone laparoscopic lymph node dissection. Other imaging findings included ectopic seeds (10 patients) and subcutaneous and intrapelvic air (11 patients). All except two patients had negative pathology reports for the removed lymph nodes. CONCLUSION: A wide variety of imaging findings may be seen after radioactive seed implantation and laparoscopic lymph node dissection, including masses that resemble necrotic lymph nodes. Radiologists should be aware of these findings in asymptomatic patients.

Brachytherapy↗
PubMed1995

Evolution of neuronal density in the ageing thalamic reticular nucleus.

In this paper we present an analysis of the visual sector of the Thalamic Reticular Nucleus (TRN) from 3, 6, 18, 24 and 30 month old Wistar rats using stereological methods. The volume density (Vv), the number of neurones per surface unit (Na) and the neurone numerical density (Nv) showed a progressive decrease between the 3rd and the 24th months as the animals aged, whereas a significant increase was observed between the 24th and the 30th month, the period at which these rodents have fully entered old age.

Age Factors↗
PubMed1995

A correlation of cell cycle perturbations with chemosensitivity in human ovarian cancer cells exposed to cytotoxic drugs in vitro.

To test the association between cytotoxicity and in vitro cell cycle perturbations we systematically studied cell cycle perturbations after exposing human ovarian cancer cells to nine commonly used cytotoxic agents. Three principal patterns of cell cycle alterations were observed: a sequential S-G2/M block after exposure to the non-phase-specific agents cis-platinum, 4-hydroperoxy-cyclophosphamide, and mitomycin C (Group I); an isolated G2/M block after exposure to the G2/M phase-specific drugs etoposide and vincristine and the non-phase-specific agent doxorubicin (Group II); and an isolated S block following exposure to the S phase-specific agents 5-fluorouracil, methotrexate, and cytosine arabinoside (Group III). Overall, there was no direct correlation between the degree of cell cycle perturbations and chemosensitivity. However, when the three subgroups of non-phase-specific agents, S phase-specific agents, and G2/M-specific agents were analyzed separately, positive correlations between the magnitude of cell kinetic alterations and chemosensitivity were observed. Cell kinetic alterations appeared to precede cytotoxicity.

Antineoplastic Agents↗
PubMed1995

The effects of steroidal contraceptives on the well-being and sexuality of women: a double-blind, placebo-controlled, two-centre study of combined and progestogen-only methods.

A placebo-controlled, double-blind study was carried out to assess the direct hormonal effects of combined and progestogen-only oral contraceptives on well-being and sexuality of women in two contrasting cultures. One-hundred-fifty women, who had been sterilised or whose partners had been vasectomised, were recruited from two centres-Manila, Philippines, and Edinburgh, Scotland. After one month pretreatment assessment, women were randomly assigned to one of three treatments (combined oral contraceptive (COC), progestogen-only pill (POP), or placebo; 50 within each treatment group, 25 per centre) and continued on treatment for four months. Assessment was by daily ratings, questionnaires and interviews. The COC adversely affected sexuality in the Edinburgh women, with 12 of the 25 women in this group also reporting the side effect of reduced sexual interest. There were modest negative effects of the combined pill on mood, more noticeable in the Edinburgh women. The POP was associated with no adverse effects on sexuality and some improvement in well-being in both centres. Possible explanations for the apparent lack of adverse effects in the Manila women are discussed. The negative effects reported may be less evident in women using the COC for contraceptive purposes but may lead to discontinuation in some women and warrant further investigation.

Adult↗
PubMed1995

HIV/AIDS prevention among female sexual partners of injection drug users in Ciudad Juarez, Mexico.

A participatory community project in the US-Mexico border town of Ciudad Juarez, aimed at helping women who are sex partners of male injection drug users to reduce behaviours which increase their risk for HIV infection, is described and evaluated. The design and implementation of the project were influenced by Paulo Freire's pedagogy in the Latin American tradition of 'popular' education, by Bandura's self-efficacy concepts, and by David Warner's 'barefoot doctor' community health care methodology. Using these approaches the participants were directly involved in the development of teaching materials, and curriculum content and implementation of the project. The programme was evaluated quantitatively using NIDA's AIDS Intake and Follow-up Assessment (AIA/AFA) questionnaires, and qualitatively using open ended interviews. While the AIA/AFA questionnaires detected small changes in the frequency of condom use among the participants, ethnographic interviews detected significant changes in the nature of the behaviours which were placing the women at risk. The changes seem to stem from an increase in the degree of self-esteem, self-efficacy and awareness of the social, economic, and political constraints of their lives. These results demonstrate the need for qualitative measures to be incorporated in the evaluation of community based health education programmes. A series of recommendations is presented to facilitate further development and replication of the programme in similar populations.

Adolescent↗
PubMed1995

[Prevalence of hepatitis B and risk factors as motivation for vaccination campaign among adolescents].

OBJECTIVES: To study the prevalence of viral Hepatitis B infection (VHB) among eighth-year EGB (basic) students; associated risk factors; and the prevalence of Hepatitis C (HC). DESIGN: A descriptive crossover study. SETTING: Eighth-year EGB students from 8 schools in Villaverde-Usera (Madrid). PARTICIPANTS: A sample of 262 individuals was used to calculate the prevalence of VHB infection (prevalence defined at 1.5%, precision = 0.015, confidence at 95% and 5% loss). MEASUREMENTS AND MAIN RESULTS: Variables were age, gender, alcohol, tattoos, drugs, family history of drugs, Hepatitis, exchanging syringes, razors, syringes, sexual relations, history of transfusions or surgery. These were obtained from a questionnaire filled in by the students themselves. The definitions were: chronic HB carrier: AgHBS+ in the blood; VHB infection: anti-HBc and/or anti-HBs positives; VHC infection: presence of anti-HC. 402 children answered the questionnaire. Serology was tested in 263 before the vaccination. Average age was 13.3 +/- 0.69. There were 52.8% males and 47.2% females. Prevalence of VHB infection was 2.28% (CI = 0.93-5.14), 6 cases. Prevalence of carriers was 0.38% (CI = 0.02-2.43; one case). There were no VHC positives. No links between VHB and risk practices could be demonstrated. CONCLUSIONS: 1) Low prevalence of VHB infection 2) The zero prevalence of VHC infection is lower than that in healthy donors.

Adolescent↗
PubMed1994

Bombesin suppresses need-free and need-induced salt intake in rats.

The researchers performed experiments to evaluate whether the effects of bombesin are selective for the satiation of ingestive behaviors related to energy balance or if ingestive behaviors associated with sodium balance are also suppressed by bombesin. Injections of 4 and 8 micrograms/kg bombesin reliably reduced need-free and sodium deficiency-induced NaCl intake in male rats. The effects of bombesin on the sodium-deficiency-induced change in taste reactivity was assessed. Injections of 4 micrograms/kg and 8 micrograms/kg bombesin had no effect on the sodium deficiency-induced shift in taste reactivity. These data indicate that bombesin suppresses NaCl intake and that bombesin does not appear to interact with gustatory sensibility in exerting its behavior-controlling action.

Animals↗
PubMed1994

[Clinicopathologic correlation in 50 cases of acquired immunodeficiency syndrome. Retrospective study].

PURPOSE: To analyze myocardial abnormalities in patients of acquired immunodeficiency syndrome with clinical and pathological correlation. METHODS: We selected 50 cases, retrospectively, age ranged from 3 months to 40 years, all of them had myocardial changes and the data of clinical records fulfilled our protocol. Cases of others cardiac diseases were not included. RESULTS: The pathological findings were: myocarditis in 33 (11 had severe myocarditis) and degenerative hystological lesions in 17. The etiologic agents detected were: Toxoplasma in 11, Cryptococcus in 7 and Cytomegalovirus in 3. In 12 cases we could not find any agent. In 15 cases occurred others lesions: endocarditis, pericarditis and sarcoma of Kaposi. It was noted tachycardia in 15 cases, decrease of heart sounds in 12, arterial hypotension in seven, systolic murmur in 8, galop rhythm in 7, pericardial friction rub in 3, arrhythmia in 2. Four patients had congestive heart failure. The EKG showed sinus tachycardia in 18, ST and T changes in 10, low voltage in 5, ST segment elevation in 5 and extrasystoles in 3 cases. The echocardiogram findings were: pericardial effusion in 9 cases and 9 had ventricular dysfunction. CONCLUSION: The cardiac lesions were very important even in patients without clinical signals. We need others prospective studies with viral identification trying to detect specific lesions of HIV.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Clinical results in 50 multiply transfused patients with severe aplastic anemia treated with bone marrow transplantation or immunosuppressive therapy.

Fifty patients with aplastic anemia (AA) were treated with BMT or immunosuppressive therapy (IST). Twenty-one patients underwent BMT using cyclophosphamide (CY) and 7 Gy total lymphoid irradiation (TLI) and cyclosporin A (CsA) plus methotrexate (MTX). Actuarial survival is 71% at 5.3 years with an incidence of graft failure of 0% and of acute GVHD of 38.9%. Univariate analysis of variables influencing survival showed a trend for a poorer outcome in patients who received > 30 transfusions prior to BMT and in male recipients from female donors. Twenty-nine patients > 40 years of age or without matched siblings received antithymocyte/antilymphocyte globulin (ATG/ALG). Response rate to the first course of treatment was 46.4%. Subsequent courses of IST rescued 33% of patients who relapsed or had not responded. Actuarial survival is 62% at 8.6 years. In our experience both treatment strategies have given encouraging results although overall morbidity is higher in the IST group because 25% of patients are therapy or transfusion-dependent. The role of irradiation in the conditioning regimen of BMT patients, recently challenged, is discussed.

Actuarial Analysis↗
PubMed1993

Evidence of tumor heterogeneity in cervical cancers and lymph node metastases as determined by flow cytometry.

BACKGROUND: The incidence and significance of tumor heterogeneity in primary tumors and metastatic lymph nodes were investigated in Stage IB-IIA cervical cancers. METHODS: Paraffin-embedded tissues from 96 radical hysterectomy specimens were dewaxed, disaggregated, and subjected to dual parameter flow cytometry. Three-dimensional histograms were generated to delineate different tumor populations. A DNA index difference of at least +/- 0.15 was used to define tumor heterogeneity. RESULTS: Mean DNA index difference of various tumor populations was 0.29 +/- 0.13. Among 69 patients with normal lymph nodes, there were 12 patients (incidence, 17.4%) with tumor heterogeneity in the primary tumors. Of 27 patients with metastatic lymph nodes, 5 (incidence, 18.5%) had evidence of tumor heterogeneity in the primary tumor, and 18 of 47 (incidence, 38.3%) had tumor heterogeneity in metastatic lymph nodes. When using DNA index to determine clonal origin of metastatic lymph nodes, as many as 60% of the metastases could not be traced to the primary tumor. Tumor heterogeneity was associated with a 40% reduction in median survival time. However, because of the small number of patients with tumor heterogeneity, statistical analyses did not show prognostic significance. CONCLUSIONS: Tumor heterogeneity appeared to be a common characteristic of early cervical carcinoma. Additional study is needed to fully evaluate its prognostic value.

Adenocarcinoma↗
PubMed1993

Demonstration of an S phase population of cells without DNA synthesis generated by cisplatin and pentoxifylline.

Dual parameter flow cytometry measuring DNA and BrdUrd uptake in "stripped" nuclei was used as a sample preparation procedure. The utility of this method is demonstrated in a human ovarian cell line (BG-1) by two parameter flow cytometric analysis of DNA and bromodeoxyuridine (BrdUrd) incorporated into the DNA. BG-1 cells, treated with cisplatin followed by constant exposure to pentoxifylline, produce G0/G1, S phase, and G2/M perturbations. The G0/G1 population is greatly diminished. Large numbers of cells are distributed in S phase in which a large portion is incapable of DNA synthesis. The G2/M perturbations show a continually increasing block over a time course of 168 h. The identification of two types of S phase cells (DNA synthesizing and DNA nonsynthesizing) is clearly shown with the use of BrdUrd incorporation as a second parameter in addition to flow cytometric analysis of DNA. This increase in the non-DNA-synthesizing S phase population corresponds to an enhancement of cytotoxicity when cells are treated with the combination of cisplatin and pentoxifylline. It is felt that this technique provides a useful method to investigate the dynamics of the cell cycle perturbations affected by modulators of chemotherapeutic agents.

Bromodeoxyuridine↗