Biomedical subjects
Publications and source records attributed to L Santos.
Whereas typhoid fever is still an endemic disease in some parts of the world, meningeal involvement in this disease is a rare occurrence. We report a case of Salmonella typhi meningitis in a 70-year-old woman. The patient was treated with ampicillin and the only sequela was right-sided deafness.
OBJECTIVE: To analyse a population with intermittent atrial fibrillation, comparing the clinical characteristics of patients with the idiopathic form with those with structural pathology. DESIGN: Intermittent atrial fibrillation retrospective study. SETTING: Arrhythmology outpatients clinic of the cardiac department. PATIENTS AND METHODS: Retrospective study of a population of 59 patients with intermittent atrial fibrillation referred to the arrhythmology outpatients clinic of the cardiac department. Forty patients were male and nineteen female with a mean age of 51 +/- 13 years. Idiopathic atrial fibrillation group with 18 patients was compared with the 41 patients group with identifiable pathology. Atrial fibrillation was recognised by 12 lead ECG and 24 hours ambulatory Holter monitoring. Clinical and echocardiographic parameters were analysed. Complications and the efficacy of anti-arrhythmic therapy were referred. MAIN RESULTS: In the studied population, mean age at the identification of atrial fibrillation was lower in the idiopathic group than in the group with identifiable pathology. It was 36 +/- 12 years in the first group and 45.2 +/- 13 in the second. Left atrium dimension was 38.1 +/- 4 mm in the first group and 42.5 +/- 9 mm in the second (p = 0.04). In the group with mitral valvulopathy, left atrium dimension was 45.5 +/- 11 mm, also significantly different from patients with the idiopathic form (p = 0.012). Statistically significative difference between those groups was not found for left ventricular end-diastolic dimension and shortening fraction. Mean follow-up was 3 years with a range between 7 months and 10 years. Effective therapeutic control was obtained in 35 of 59 patients (59.3%). Six were from the idiopathic group (33.3%) and 29 from the group with identifiable pathology (70.7%). Control was not reached or was only partial in 24 patients (40.7%), belonging 66.7% to the first group and 29.3% to the second (p = 0.016). No embolic phenomenon was documented in the idiopathic not anti-coagulated group. Four embolic complications (9.8%) were observed in the group of identified pathology. Three of then were related with mitral valvulopathy and were submitted to effective anti-coagulation therapy. CONCLUSIONS: Patients with idiopathic intermittent atrial fibrillation are younger, with smaller left atrium dimension (mainly in relation to those with mitral valve disease) but are more resistant to anti-arrhythmic therapy. They have a trend to less thromboembolic complications and anti-coagulation is probably not justified.
Orthotopic Liver Transplantation (OLT) is the only surgical approach to non-resectable hepatocellular carcinoma (HCC) but, so far its results has been poor. During 41 months 112 patients underwent 123 OLT, nine of them had HCC over cirrhosis with a mean age 60 years. The etiology of cirrhosis was: alcohol in 1 and viral hepatitis in 8. Child's grade: A in 4, B in 5. HCC was: 5 cm or less in 5 and more in 4. According pTNM staging: I in one, II in 5, II in 2 and IVb in 1. Differentiation degree: low in 1, moderate in 4, and well in 3 (one case with complete necrosis after embolization). Eight patients were previously embolized with lipiodol, adriamycin and gelfoam, obtaining central necrosis without viable features in periphery. There were no postoperative deaths, and all the patients were discharged from the hospital. During follow up, 3 recurrences were observed, one massive with death of the patient after 6 months, and the other was surgically removed (segmentectomy V, VI) after 4 months after OLT without recurrence at 18 months of resection. In the third case a focal lesions was detected in the U.S. and T.C. study, 4 months after OLT, but in wasn't possible to obtain a biopsy because its posterior location; no treatment was made, and she's alive today. In conclusion, OLT is a good surgical option for non resectable HCC complicating cirrhosis if the patient is adequately selected. Chemoembolization has a good local effect, obtaining tumoral necrosis, but it does not decrease the posterior growth of the tumor in other localizations.
PURPOSE: To investigate if hyper-homocysteinemia represents an independent risk factor of early coronary disease. METHODS: We studied a group of patients under 45 years old, that suffered a myocardial infarction from 3 months and 1 year before the study. The patients were matched with a group of normal controls of a check-up program, in terms of age, sex, smoking habits, presence of hypertension, obesity, (Quetelet Index), presence of diabetes, basal glycemia, total cholesterol, LDL and HDL cholesterol. Later we measured to patients (Pts) and controls (Cts) the plasmatic basal homocysteinemia (B HC) and 6 hours after a methionine overload of 0.1 g/kg body weight (L HC). RESULTS: [table: see text] CONCLUSIONS: In this study hyper-homocysteinemia appears as an independent risk factor of early coronary disease. The measurement of homocysteinemia after the methionine loading test was more discriminative than the basal measurement.
We conducted a prospective study of a smoking ban on a general inpatient psychiatry service in response to staff concerns about the feasibility of a proposed hospital-wide ban. Demographic information, smoking history, and DSM III-R diagnoses were obtained for consecutively admitted patients during two study conditions: smoking and nonsmoking. A log of p.r.n. medication, seclusion, restraint, elopement, incident reports, and smoking-related discharges was kept for each patient. Chi-square analysis of 232 patients for whom demographic, smoking, diagnostic, and log data were complete showed no significant differences between study conditions for demographic or diagnostic variables. Two-tailed t-test analysis of the log data for these 232 patients showed no significant difference in disruptive incidents during smoking and nonsmoking conditions (p = 0.183). Fifty staff members answered pre- and post-ban questionnaires. Paired t-test analysis demonstrated a significant change in staff attitude toward supporting the ban. These data indicate that smoking can be stopped on inpatient psychiatry units without increases in unit disruption or adverse effects on staff morale.
OBJECTIVE: To assess the prognosis of Unstable Angina according to its clinical presentation using Braunwald's Classification. DESIGN: Retrospective study of hospital admissions from January 1982 to September 1990. SETTING: Coronary Care Unit and a Cardiology Department of a Central Hospital. PATIENTS: There were 132 patients, 109 men and 23 women, with a mean age of 56 +/- 9 years, all submitted to cardiac catheterization at least 90 days after hospital admission followed up during 34.2 +/- 24.2 months. MATERIAL AND METHODS: Patients were divided in three groups according to the clinical presentation of Unstable Angina: Group A--Aggravated Chronic Angina and/or "De Novo" Angina; Group B--Angina at Rest but not in the last 48 hours, and Group C--Angina at Rest in the last 48 hours. Group A was also sub-divided, and the patients with Unstable Angina after myocardial infarction were excluded. The previous clinical profile was evaluated as well as the circumstances in which Unstable Angina occurred, need of Coronary Care Unit, angiographic findings and follow-up. RESULTS: Within the 132 patients, 86 were in the group A, (59 with Aggravated Angina and 27 with "De Novo" Angina), 11 in group B, and 35 in group C. The group with Aggravated Angina had higher incidence of previous myocardial infarction and bypass surgery (p < 0.01 and p = 0.05), compared to group with "De Novo" Angina and B, and also three vessels disease associated to ventricular dysfunction. "Culprit Lesion" appeared more frequently as eccentric type I in group A, and as concentric in group C. Revascularization procedures were performed in 95 patients (CABG in 66 and PTCA in 29) being respectively: 21 and 6 were urgent, 19 and 18 were elective and 26 and 5 were late procedures. CABG were more frequent in group A. There were 73 major cardiac events in 44 patients (8 deaths, 12 myocardial infarction and 53 new episodes of Unstable Angina), which were more frequent in group with Aggravated Angina and group C. The chance of patients with major cardiac events was in a 78 months follow-up, about 25% for group with "De Novo" Angina, 50% for patients with Aggravated Chronic Angina, and was greater than 75% in patients with Angina at Rest and episodes in the last 48 hours (p < 0.05)--Log-rank Test. The worse prognosis was seen in patients with Aggravated Chronic Angina, when a gathering of clinic patterns of Braunwald's classification were present. CONCLUSIONS: In summary, the group with Aggravated Angina and group C had more severe disease, required more urgent CABG and PTCA, and had also a higher incidence of cardiac events. The group with better prognosis was the group with "De Novo" Angina, which should be distinguished of the group with Aggravated Angina who was the worst prognosis.
1,4-Dihydropyridine (DHP) derivatives with a 1,2-benzisothiazol-3-one 1,1-dioxide group, linked through an alkylene bridge to the C-3 carboxylate of the DHP ring, with both vasoconstricting and vasorelaxant properties were obtained. In blocking Ca(2+)-evoked contractions of K(+)-depolarized rabbit aortic strips, compounds 12 and 41 were 10-fold more potent than nifedipine; 27 other compounds were 1-4-fold more potent. Their vascular versus cardiac selectivity was very pronounced; for instance, the selectivity index for compound 41 was 70-fold higher than that of nifedipine. This was also true for the vasoconstricting compound 22, which was as potent as Bay K 8644 in enhancing the Ca(2+)-evoked contractions of rabbit aorta strips, yet it had poor inotropic activity in rabbit left atria. Oral administration of compounds 38, 40, 43, and 53 (20 mg/kg) caused a 35-37% decrease in systolic blood pressure in spontaneously hypertensive rats (SHR); these effects were similar to those of nifedipine. However, iv administration of these compounds to anesthetized SHR caused a decrease in blood pressure which was more pronounced and long-lasting than that of nifedipine. When administered iv at 100 micrograms/kg, the vasoconstricting compound 22 caused a 40% increase in systolic and diastolic blood pressure. Compound 22 exhibited an unusually interesting feature over the other five Ca2+ DHP agonists: it had diester substitutions at the C-3 and C-5 positions of the DHP ring. Overall, compounds possessing these properties might be useful in treating clinical cardiovascular conditions in which DHP Ca2+ antagonists or agonists are indicated.
We compared the depth of the anterior chamber and the optimal distance refraction in a group of patients with soft and rigid intraocular implants under pilocarpine (maximal ciliary contraction) and cyclopentolate (maximal ciliary relaxation) in order to determine if lens movement might account for the apparent accommodation phenomenon. Lens shifts ranging from 1.5 to 0.02 mm and refractive variations up to 1 D were found. However, the discrepancies between amount of shift and refractive variations suggest that lens movement does not play a relevant role in this phenomenon.
The electron affinity of some glyoxylic compounds with radiosensitizing properties was evaluated using different approaches. The half-wave reduction potentials were measured by polarography, and the molecular structures in solution were determined by NMR spectroscopy. The electron affinity of the unhydrated and hydrated molecules was theoretically evaluated by means of a semi-empirical quantum mechanical procedure, the MNDO. The possible correlations between these values and the radiosensitizing efficiency of these glyoxylic compounds is discussed.
The pathology of the major vessels also affects microcirculation, making possible to evaluate at the distal sector the consequences of an ischaemia, due to an artery disease, for instance. This work had as its main aim to evaluate by peri-ungueal capillaroscopy (PUC) the lesions due to an atherosclerotic process and the prognosis and/or diagnosis value of this exam. We studied 210 patients with either risk factors for atherosclerosis or atherosclerotic disease, who were divided into groups according to the severity of the lesions seen in PUC. Finally, we were able to conclude that although the capillaroscopic lesions found are not specific, they appear very early in the process and are more serious in the more severe cases.
A new series of 4-alkyl-1,4-dihydropyridines (1,4-DHP) were synthesized and evaluated for their ability to inhibit washed rabbit platelet aggregation induced by PAF-acether (1-O-hexadecyl/octadecyl-2-O-acetyl-sn-glycero-3-phosphorylcholine) and to reverse PAF-induced hypotension in anesthetized rats. Additionally, compounds were evaluated for their ability to inhibit the binding of radiolabeled PAF to its receptor on rabbit platelets. Among these compounds, 6I and 6L were the most potent and specific antagonists. At concentrations up to 100 microM, neither compound 6I nor compound 6L caused platelet aggregation nor did they inhibit platelet aggregation induced by collagen or adenosine diphosphate. Compound 6L did not show in vitro calcium channel blocker activity measured on vascular smooth muscle preparations of rabbit aorta and on [3H]nitrendipine binding assays. The compound did not show any cardiovascular effects in anesthetized rat at iv doses up to 1000 micrograms/kg, and the Ki value was 568.62 nmol. These results indicate that compound 6L is a potent and specific PAF antagonist with 1,4-dihydropyridine structure but devoid of a significant cardiovascular activity related to calcium-antagonist properties.
Nine healthy volunteers were studied before, during, and after ingesting a fermented dairy product containing Lactobacillus acidophilus, Bifidobacterium bifidum, and mesophilic cultures (Streptococcus lactis and S cremoris) for 3 wk. Hydrogen and methane productions and fecal beta-galactosidase and beta-glucosidase activities were measured as indicators of fermentation capacity of the colonic flora. Fecal concentrations of nitroreductase, azoreductase, and beta-glucuronidase, which may be implicated in colonic carcinogenesis, were also assessed. Hydrogen and methane productions, fecal beta-galactosidase, beta-glucuronidase, and azoreductase activities did not change over three 3-wk periods whereas fecal beta-glucosidase activity increased (42 +/- 6, 91 +/- 12, and 40 +/- 6 IU/g N, P less than 0.01) and nitroreductase decreased (0.87 +/- 0.13, 0.54 +/- 0.11, and 0.57 +/- 0.08 IU/g N, P less than 0.05).
To detect molecules of Entamoeba histolytica involved in the trophozoite-target cell interaction, three different antisera were generated: (a) two rabbit antisera, one against total amebic proteins and another directed specifically to the 112-kDa adhesin; and (b) a mouse antiserum against amebic molecules adhering to the red blood cell (RBC) surface after incubation of RBCs with total soluble protein from trophozoites (anti-adhesion serum). All three antisera recognized the 112-kDa adhesion. Adhesion of this molecule to the RBC surface was temperature-dependent. More of the 112-kDa adhesion was found on the surface of RBCs incubated with trophozoites at 37 degrees C than on RBCs incubated at room temperature or at 0 degree C. Experiments using both anti-adhesin and anti-total ambebic protein sera revealed the presence of 210, 160, 112, 90, 70, 50, and 24-kDa proteins on RBC incubated with trophozoites. Surface proteins obtained from iodinated MDCK cells recognized amebic proteins of 112, 90, and 48-50 kDa. Virulence-deficient mutants presented a similar amount of the 112-kDa adhesin to the wild-type strain. However, in mutants, the adhesion was not functional, since they did not adhere to RBCs. 90- and 24-kDa proteins were also found to be altered in mutants.
The radiosensitizing effects of five newly synthesized quaternary salts of 5-nitroimidazole derivatives on the survival of TC-SV40 mammalian cells have been measured. A toxicity study was carried out in order to determine the concentrations to be used in the radiosensitizing experiments. The oxygen enhancement ratio (OER) for TC-SV40 cells was 2.74. None of the five 5-nitroimidazole derivatives showed radiosensitizing activity in aerobic conditions, while in hypoxia their dose-modifying factors (DMF) at the concentration of 0.2 mmol dm-3 range from 1.52 to 1.03 in this order: unsubstituted pyridinium greater than carbamoyl pyridinium greater than trimethyl pyridinium greater than t-butyl pyridinium greater than imidazolium. This latter product at the concentration of 2 mmol dm-3 has a DMF of 1.64. As comparison, metronidazole was also tested on this cell line and its DMF at 0.2 mmol dm-3 was 1.35. The response-concentration dependences for the unsubstituted pyridinium 5-nitroimidazole derivative and for metronidazole (comparing charged and uncharged structures) showed the flattening response-concentration curve of quaternary compounds. The electron affinity was evaluated through the CNDO/S theoretical method, and an exponential relationship between these values and the DMFs of the pyridinium derivatives was demonstrated.
The effects of four pyridinium and one imidazolium derivatives of 5-nitroimidazole have been tested for their action on the kinetics of DNA semiconservative synthesis and of the unscheduled DNA synthesis carried out by TC-SV40 cells. Unscheduled synthesis was induced by 25 Gy X-rays, and the kinetics were evaluated through the measurement of the newly synthetized DNA labelled with [3H-methyl]thymidine. All derivatives inhibit the DNA semiconservative synthesis and increase the unscheduled DNA synthesis to different degrees, but not in the suitable way to reveal the mechanism of interaction with DNA as responsible of the product's radiosensitizing actions on the same mammalian tumor cells.
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The effect of the pH of dissolutions of weakly acidic beta-lactam antibiotics on their intestinal absorption has been studied by quantification of the contribution of the ionized and un-ionized antibiotic forms to the whole absorptive process. In vivo recirculation in both sexes of adult Wistar rats was performed with buffer solutions at different pH values and samples were analyzed by high-performance liquid chromatography (HPLC).
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