PubMed Health⌕ Search

Biomedical subjects

P Smets

Publications and source records attributed to P Smets.

At least 19 recordsLinked to original sources
PubMed1999

Antiplatelet treatment does not reduce the severity of subsequent stroke. European Stroke Prevention Study 2 Working Group.

OBJECTIVE: To assess the the effect of antiplatelet therapy on the severity of subsequent stroke in patients with stroke and TIA. BACKGROUND: The Second European Stroke Prevention Study (ESPS2) recruited 6,602 patients in four treatment groups: placebo, 2 x 25 mg acetylsalicylic acid (ASA), 2 x 200 mg dipyridamole (DP), and the combination of 50 mg ASA and 400 mg DP per day. Seventy-six percent of the patients had had a stroke as the qualifying event, whereas 24% had a TIA. All patients were followed at 3-month intervals for 2 years. ESPS2 showed a benefit from antiplatelet treatment compared with placebo and an additional benefit using ASA and DP together compared with either of these antiplatelet agents alone. METHODS: In the ESPS2, the study protocol included assessment of severity of end point stroke with the modified Rankin scale once the stroke had clinically stabilized, and no further impairment was observed. There were 824 new stroke events during follow-up. In 701 of them, the initial Rankin scale was known, and this was also evaluated after each nonfatal recurrent stroke. The difference in Rankin scale between treatment groups was analyzed after recurrent stroke, and the progress in Rankin scale between entry and recurrent stroke was quantified by calculating the number of patients with a change of one or more degrees in the scale. RESULTS: There were no significant differences in these changes in Rankin scale between the treatment groups. The mean time to reach an end point of stroke was longest in patients who used ASA + DP (p = 0.057). However, there was no difference among the treatment groups in the time to death during follow-up. CONCLUSION: This study suggests that antiplatelet therapy does not influence the severity of recurrent stroke as evaluated with the Rankin scale. However, antiplatelet therapy seems to lengthen the time the patient remains free from a recurrent stroke.

Aged↗
PubMed1999

Second European Stroke Prevention Study: antiplatelet therapy is effective regardless of age. ESPS2 Working Group.

BACKGROUND: The Second European Stroke Prevention Study (ESPS2) was a randomized, placebo-controlled trial that investigated the efficacy of low-dose acetylsalicylic acid (ASA) and modified-release dipyridamole (DP), alone or in combination, in the secondary prevention of ischemic stroke. The trial demonstrated that the combination was significantly more effective than either agent used alone. The aim of the present study was to evaluate the influence of age on the efficacy of ASA and DP, alone or in combination, in the secondary prevention of stroke in the ESPS2 population. METHODS AND RESULTS: A total of 6602 patients were recruited to the ESPS2 and there were 4 treatment groups: ASA (25 mg twice daily), DP (200 mg twice daily), ASA and DP in a combined formulation, or placebo. Primary endpoints were stroke, death, and stroke or death together. The endpoints evaluated in the present study were stroke, stroke and/or death, and vascular events. Stroke was the qualifying event in 76% of the patients, while 24% had a transient ischaemic attack. Patients were reviewed at 3-month intervals for 2 years. The study population consisted of 2565 (39%) patients aged less than 65 years, 2240 (34%) patients aged between 65 and 74 years, and 1797 (27%) patients aged 75 years and over. Advancing age was associated with an increased incidence of endpoints in all 4 treatment groups. The combination of ASA and DP significantly reduced the incidence of all endpoints, compared with placebo, in each age group. There was no influence of age on the efficacy of antiplatelet therapy for any of the evaluated endpoints. Relative risk reductions of treatment compared with placebo were 11.1-27.6% in the ASA group, 8.0-18.7% in the DP group, and 20.3-45.2% in patients receiving combination therapy. CONCLUSION: This study clearly demonstrates that combination therapy with DP and ASA is superior to either agent used alone in the secondary prevention of ischemic stroke, irrespective of the age of the patient.

Administration, Oral↗
PubMed1999

Origins of Falasha Jews studied by haplotypes of the Y chromosome.

DNA samples from Falasha Jews and Ethiopians were studied with the Y-chromosome-specific DNA probe p49a to screen for TaqI restriction polymorphisms and haplotypes. Two haplotypes (V and XI) are the most widespread in Falashas and Ethiopians, representing about 70% of the total number of haplotypes in Ethiopia. Because the Jewish haplotypes VII and VIII are not represented in the Falasha population, we conclude that the Falasha people descended from ancient inhabitants of Ethiopia who converted to Judaism.

Adult↗
PubMed1998

Use of an intramedullary hip-screw compared with a compression hip-screw with a plate for intertrochanteric femoral fractures. A prospective, randomized study of one hundred patients.

One hundred elderly patients who had an intertrochanteric femoral fracture were randomized to treatment with a compression hip-screw with a plate (fifty patients) or a new intramedullary device, the intramedullary hip-screw (fifty patients). All patients were followed prospectively for one year or until death. A detailed assessment of the functional status and the plain radiographs of the hip was performed one, three, six, and twelve months postoperatively. The two treatment groups were strictly comparable. The operative time needed to insert the intramedullary hip-screw was significantly greater than that needed to insert the compression hip-screw with the plate (p = 0.02), but use of the intramedullary hip-screw was associated with less estimated intraoperative blood loss (p = 0.011). The prevalence of perioperative complications, such as bronchopneumonia, cardiac failure, and urinary tract infection, was comparable in the two treatment groups. There were one intraoperative fracture of the femoral shaft and two intraoperative fractures of the greater trochanter in the group managed with the intramedullary hip-screw. One patient had pulling-out of the compression hip-screw on the seventh postoperative day. Four patients had a trochanteric wound hematoma, without infection, after insertion of an intramedullary hip-screw. All but one of the fractures healed. The one non-union, which was in a patient who had a compression hip-screw, was treated with a hemiarthroplasty. The mortality rate was similar in the two treatment groups. The patients who had an intramedullary hip-screw had, on the average, significantly better mobility at one (p < 0.0001) and three months (p = 0.0013) postoperatively. This difference was no longer seen at six and twelve months, although the patients who had an intramedullary hip-screw still had significantly better walking ability outside the home at those time-periods (p = 0.05). The compression hip-screw was removed from two patients because of pain in the mid-portion of the thigh, which had begun after consolidation of the fracture. Fourteen patients who had an intramedullary hip-screw had cortical hypertrophy at the level of the tip of the nail at twelve months postoperatively. Cortical hypertrophy was significantly related to the use of two interlocking screws (p = 0.02). Six of these patients also had pain in the mid-portion of the thigh, and the nail had been locked with two screws in five of them. Three of the six patients had the hardware removed because of the pain, and the symptoms resolved. A seventh patient had pain without cortical hypertrophy. The intramedullary hip-screw device was associated with significantly less sliding of the lag-screw and subsequent shortening of the limb in the region of the thigh (p = 0.012 and 0.019, respectively); these differences were more pronounced when the unstable fractures in the two treatment groups were compared (p < 0.001).

Aged↗
PubMed1997

Profound immunosuppression across the spectrum of opportunistic disease among hospitalized HIV-infected adults in Abidjan, Côte d'Ivoire.

OBJECTIVES: To describe the spectrum of opportunistic disease in HIV-infected patients admitted to hospital in Abidjan, Côte d'Ivoire, and to describe the level of immunosuppression at which these diseases occur. DESIGN: Cross-sectional study. SETTING: In-patient wards of the University Hospital Infectious Diseases Unit. PATIENTS: A total of 250 adult patients recruited by systematic sampling at the point of hospital admission. MAIN MEASURES: HIV status; CD4 count; diagnoses, confirmed by microbiological/radiological investigations whenever possible; and outcome of hospitalization (death or discharge). RESULTS: Overall, 79% patients were HIV-positive. The most frequent diagnoses in HIV-positive patients were septicaemia (20%, with non-typhoid salmonellae, Escherichia coli and Streptococcus pneumoniae the most common organisms), HIV wasting (16%), meningitis (14%), tuberculosis (TB; 13%), isosporiasis (10%), cerebral toxoplasmosis (7%) and bacterial enteritis (7%). Most HIV-positive patients had evidence of severe immunosuppression: 39% had CD4 counts < 50 x 10(6)/l, 17% had 50-99 x 10(6)/l, and 20% had 100-199 x 10(6)/l. In-hospital mortality among HIV-positive patients was 38% compared with 27% among HIV-negative patients [age-adjusted odds ratio (OR), 1.5; 95% confidence interval (CI), 0.7-2.9]. Among HIV-positive patients, the highest case-fatality rates were among patients with meningitis, toxoplasmosis and TB: in a multivariate analysis the strongest independent risk factors for death were an abnormal level of consciousness (OR, 9.3; 95% CI, 3.5-24.6), a haemoglobin concentration below 8 g/dl (OR, 4.2; 95% CI, 1.4-12.8) and age > 40 years (OR, 3.9; 95% CI, 1.5-10.2). CONCLUSIONS: Our data show that, as in industrialized countries, most HIV-infected individuals admitted to and dying in hospital in Abidjan are profoundly immunosuppressed. Potentially preventable infections are the main causes of in-hospital morbidity and mortality among HIV-infected persons in Abidjan, and the evaluation of appropriate primary prophylactic regimes is a priority.

AIDS-Related Opportunistic Infections↗
PubMed1996

European Stroke Prevention Study. 2. Dipyridamole and acetylsalicylic acid in the secondary prevention of stroke.

In 1988, we undertook a randomized, placebo-controlled, double-blind trial to investigate the safety and efficacy of low-dose acetylsalicylic acid (ASA), modified-release dipyridamole, and the two agents in combination for secondary prevention of ischemic stroke. Patients with prior stroke or transient ischemic attack (TIA) were randomized to treatment with ASA alone (50 mg daily), modified-release dipyridamole alone (400 mg daily), the two agents in a combined formulation, or placebo. Primary endpoints were stroke, death, and stroke or death together. TIA and other vascular events were secondary endpoints. Patients were followed on treatment for two years. Data from 6,602 patients were analysed. Factorial analysis demonstrated a highly significant effect for ASA and for dipyridamole in reducing the risk of stroke (p < or = 0.001) and stroke or death combined (p < 0.01). In pairwise comparisons, stroke risk in comparison to placebo was reduced by 18% with ASA alone (p = 0.013); 16% with dipyridamole alone (p = 0.039); and 37% with combination therapy (p < 0.001). Risk of stroke or death was reduced by 13% with ASA alone (p = 0.016); 15% with dipyridamole alone (p = 0.015); and 24% with the combination (p < 0.001). The treatment had no statistically significant effect on the death rate alone. Factorial analysis also demonstrated a highly significant effect of ASA (p < 0.001) and dipyridamole (p < 0.01) for preventing TIA. The risk reduction for the combination was 36% (p < 0.001) in comparison with placebo. Headache was the most common adverse event, occurring more frequently in dipyridamole-treated patients. All-site bleeding and gastrointestinal bleeding were significantly more common in patients who received ASA in comparison to placebo or dipyridamole. We conclude that (1) ASA 25 mg twice daily and dipyridamole, in a modified-release form, at a dose of 200 mg twice daily have each been shown to be equally effective for the secondary prevention of ischemic stroke and TIA; (2) when co-prescribed the protective effects are additive, the combination being significantly more effective than either agent prescribed singly; (3) low-dose ASA does not eliminate the propensity for induced bleeding.

Adult↗
PubMed1993

Antiplatelet therapy is effective in primary prevention of myocardial infarction in patients with a previous cerebrovascular ischemic event.

OBJECTIVE: A secondary subgroup analysis of the European Stroke Prevention Study of the effect of antiplatelet medication on the risk of myocardial infarction. DESIGN AND SETTING: A randomized, double-blind placebo-controlled study with two parallel treatment groups (dipyridamole plus aspirin and placebo). Sixteen centers from six countries participated in the study. PATIENTS: A total of 2500 patients who had had one or more transient ischemic attacks or cerebral infarctions participated. INTERVENTION: Combination therapy with dipyridamole (75 mg three times a day) and aspirin (330 mg three times a day) was compared with placebo during 24 months' follow-up. OUTCOME MEASURES: Prevention of fatal and nonfatal myocardial infarction. RESULTS: A total of 105 myocardial infarctions occurred in the intention-to-treat analysis and 76 occurred in the explanatory analysis. The overall risk reduction of myocardial infarction with the study drugs was approximately 40% in both statistical analyses, but the result was statistically significant only in the intention-to-treat analysis. Therapeutic efficacy was better among male patients, patients younger than 65 years, and patients with hypertension. CONCLUSION: Combination therapy with dipyridamole and aspirin reduces not only the risk of cerebrovascular ischemic events but also the risk of myocardial infarction.

Aged↗
PubMed1993

European Stroke Prevention Study (ESPS): antithrombotic therapy is also effective in the elderly.

The ESPS was a multicenter study comparing the effect of the combination of dipyridamole 75 mg and acetylsalicylic acid 330 mg t.i.d. to placebo in 2500 patients (intention-to-treat analysis) and 1861 patients (explanatory analysis) in the secondary prevention of stroke or death after one or more attacks of TIA, RIND or stroke of atherothrombotic origin. End-point reduction was evaluated in two age groups, those not older than 65 years (1358 patients) and those who were older than 65 years (1142 patients). End-point reduction was significantly greater in patients with active therapy than in the placebo group in both age groups. Subgroup analyses with stroke as an end-point indicated that younger patients with TIA (< or = 65 years) had lower risk of stroke than those > 65 years or patients with stroke. The overall risk reduction was best in TIA patients > 65 years of age. The risk reduction with study medication was 40-50% in both sexes and in both age groups. Thus, age of the patient does not influence the efficacy of antithrombotic therapy. However, since these results are obtained from a secondary analysis of a subgroup of patients, the results may need confirmation by further studies.

Actuarial Analysis↗
PubMed1993

Y-chromosome-specific haplotype diversity in Ashkenazic and Sephardic Jews.

DNA samples from Ashkenazic and Sephardic Jews were studied with Y-chromosome-specific DNA probes p49f and p49a to screen for RFLPs and haplotypes. All 16 European haplotypes were found in Jews, but only 2 of them (VII and VIII) were widespread. Haplotype distributions in the two Jewish populations are similar, but haplotypes XI and XV are more frequent in the Ashkenazim and haplotypes IV and V are more frequent in the Sephardim, indicating their origins.

Adult↗
PubMed1992

Inhibition of production of tumor necrosis factor by monoclonal antibodies to lipopolysaccharides.

Murine monoclonal antibodies to lipopolysaccharides (LPS) from rough J5 mutant of Escherichia coli O111:B4 protected D-galactosamine-treated mice against lethal effects of LPS and provided protection in an experimental infection model with live E. coli. Three previously prepared anti-LPS antibodies were evaluated for ability to inhibit LPS-induced tumor necrosis factor (TNF) secretion. In vivo, TNF production was induced in mice treated with D-galactosamine and challenged with LPS. Two antibodies (D6B3 and D6B4) decreased serum TNF levels and prevented lethal effects of LPS. Nonprotective anti-LPS antibody (D9A2) and an unrelated antibody to neomycin did not reduce circulating TNF levels after LPS challenge. Pretreatment of mice with D6B3 and D6B4 protected mice from infection with E. coli and prevented serum TNF increases induced by E. coli infection. In nonprotected animals, high levels of TNF were detected in serum 3-6 h after infection; animals died within 24 h. In vitro, addition of protective antibodies to macrophage cultures at initiation of LPS stimulation inhibited TNF production. Nonprotective antibody D9A2 failed to block LPS-induced TNF production.

Animals↗
PubMed1992

European stroke prevention study: effectiveness of antiplatelet therapy in diabetic patients in secondary prevention of stroke.

BACKGROUND AND PURPOSE: The European Stroke Prevention Study was a multicenter trial comparing the effect of a combination of 75 mg dipyridamole and 330 mg acetylsalicylic acid three times a day with the effect of a placebo in the prevention of stroke or death in 1,861 patients after one or more episodes of recent transient ischemic attack or cerebral infarction. METHODS: The present study represents a secondary analysis of the efficacy of study medication in diabetic (n = 216) and nondiabetic (n = 1,645) patients. RESULTS: The risk of end point events was greater in diabetic than in nondiabetic subjects. Total end point reduction in individuals receiving the combination of dipyridamole and acetylsalicylic acid was 39% in nondiabetic subjects and 23% in diabetic subjects in the explanatory analysis, and the reduction in the risk of stroke was 48% and 32%, respectively. However, a statistically significant reduction of risk was obtained only in nondiabetic subjects. CONCLUSIONS: The combination of dipyridamole and acetylsalicylic acid appeared to be more effective in nondiabetic subjects than in diabetic subjects in the prevention of death and stroke although the low number of diabetic patients may at least in part explain this result.

Aged↗
PubMed1991

Structure of the O-specific polysaccharide chain from Klebsiella pneumoniae O1K2 (NCTC 5055) lipopolysaccharide.

The structure of the O-specific polysaccharide of Klebsiella pneumoniae O1K2 lipopolysaccharide was investigated by use of methylation, periodate oxidation, partial hydrolysis, and 1H- and 13C-n.m.r. spectroscopy. It was shown to consist of a linear chain composed of two disaccharide repeating units, [----3)-alpha-D-Galp-(1----3)-beta-D-Galp-(1----] and [----3)-alpha-D-Galp-(1----3)-beta-D-Galf-(1----].

Carbohydrate Sequence↗
PubMed1991

The European Stroke Prevention Study (ESPS): results by arterial distribution.

The European Stroke Prevention Study was a multicenter study comparing the effect of the combination of dipyridamole, 75 mg, and acetylsalicylic acid, 330 mg, three times a day, to that of placebo in 2,500 patients in the secondary prevention of stroke or death after one or more transient ischemic attacks, reversible ischemic neurological deficits, or strokes of atherothrombotic origin. The patients with vertebrobasilar events at entry comprised one-third of the whole patient population. The overall total incidence of stroke or death (the end points) during the 2-year follow-up in the placebo group was lower in the vertebrobasilar group compared to the carotid group (14% versus 24%, respectively). The combination therapy of dipyridamole and acetylsalicylic acid caused a marked reduction in the incidence of stroke or death in patients with vertebrobasilar (51%) and carotid (30%) events. When only stroke was considered as the end point, dipyridamole and acetylsalicylic acid seemed to be more effective in reducing the risk of transient ischemic attacks than stroke, and more effective in men than in women.

Aspirin↗
PubMed1991

A skin suction blister model in hairless rats: application to the study of anti-inflammatory and immunomodulatory drugs.

A suction blister model was developed in the hairless rat, in order to study the effects of various agents on the migration of polymorphonuclear leukocytes (PMN). A standardized abrasion, a suction blister, was formed by applying negative pressure to the skin and then separating the epidermis from the dermis. A migration chamber containing serum as the chemoattractant was placed over the wound. After 6 h of migration, the cells in the chamber were harvested, counted and identified. We evaluated PMN migration after treating the animals with active compounds: niflumic acid, and anti-inflammatory drug, and RU 41740, an immunomodulator. This in vivo model provided reproducible data and could be used to study further the functional properties of PMN. In addition, because this assay can also be used in man, a drug found to be effective in the animal system could then be tested for its activity in man.

Adjuvants, Immunologic↗
PubMed1991

Toxicity and activity of purified trichosanthin.

Trichosanthin was purified from fresh Chinese root tubers of Trichosanthes kirilowii and evaluated for anti-HIV activity. Trichosanthin inhibited syncytium formation between infected H9 cells and uninfected Sup-T1 cells from 0.5 to 4 micrograms/ml. Trichosanthin also inhibited HIV replication in H9 and CEM-SS cells at 1 microgram/ml, but was toxic for MT-4 cells (HTLV-I-positive), at doses greater than 0.25 microgram/ml. This new purification procedure confirms the anti-HIV activity of trichosanthin on some cell lines in different biological assays.

Amino Acids↗