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Biomedical subjects

M David

Publications and source records attributed to M David.

At least 145 records · Page 8Linked to original sources

Hemoglobins in Togolese newborns: Hb S, Hb C, Hb Bart's, and alpha-globin gene status.

The gene frequency of the most important hemoglobin (Hb) abnormalities is reported in a population of 171 Togolese newborns. Hb phenotypes, hematological parameters, and the more frequently described alpha-gene deletions were analyzed. Structural abnormalities of beta-globin were observed in 35.7% of the children with a gene frequency of 0.105 for beta(S) and 0.091 for beta(C). The frequency of the different alpha-globin genotypes was alpha alpha/ = 0.71, -alpha/ = 0.28, and alpha alpha alpha/ = 0.01. All of the individuals homozygous for the -alpha genotypes, and most of the heterozygous individuals, carried Hb Bart's. Within the alpha alpha/alpha alpha and the -alpha/alpha alpha groups, several individuals with or without Hb Bart's were found; they did not differ from the others by their red blood cell (RBC) parameters but by their levels of fetal hemoglobin (Hb F). The African alpha2 polymorphism marker, characterized by the replacement of G by TCGGCCC at position 7238 (EMBL HSHBA4, 1993) and of T 7174 by G, was found in 21 newborns. The mean value of Hb F was calculated for each genotype, the mean (G)gamma percentage was 69.4 +/- 4.0%, and the gene frequency of the AgammaT marker was 0.10; this marker was linked to the normal beta-globin cluster.

Blood Cell Count↗

Osteogenesis imperfecta with joint contractures: bruck syndrome.

We describe an Egyptian boy with osteogenesis imperfecta who was born with thumb contractures and bilateral antecubital pterygia. He was seen at 16 months of age with femur and tibial fractures, thoracic vertebral compression fractures, scoliosis and Wormian bones. The findings are consistent with a diagnosis of Bruck syndrome.

Abnormalities, Multiple↗

Incidence and risk factors of catheter-related deep vein thrombosis in a pediatric intensive care unit: a prospective study.

OBJECTIVE: To estimate the incidence and to characterize risk factors for central venous catheter (CVC)-related deep vein thrombosis (DVT) in a pediatric intensive care unit. STUDY DESIGN: Consecutive children admitted to a pediatric intensive care unit who required a CVC for more than 48 hours were examined by Doppler ultrasonography of the catheterized vein at days 2, 4, 6, or 7 after insertion and weekly thereafter until CVC removal. RESULTS: The incidence of CVC-related DVT was 18.3% (17 of 93) (95% confidence interval = 10.2% to 25.8%). Thromboses were diagnosed within the first 4 days of catheter placement for 15 of 17 CVC-related thromboses. Multivariate analysis showed that risk factors most predictive of CVC-related DVT were presence of a cancer (odds ratio = 17.23, 95% confidence interval = 1.5 to 194) and young age (odds ratio for age = 0.72, 95% confidence interval = 0.54 to 0.96). CONCLUSION: The frequency of CVC-related DVT is substantial in pediatric intensive care units. Risk is highest during the 4 days after insertion and decreases thereafter. The clinical impact, optimal prevention, and therapy of these thromboses remain to be determined.

Catheterization, Central Venous↗

Nitroglycerin to facilitate fetal extraction during cesarean delivery.

OBJECTIVE: To determine the efficacy of nitroglycerin in easing fetal extraction in elective cesarean deliveries in comparison with placebo and to collect maternal and fetal pharmacologic data after administration of nitroglycerin. METHODS: This randomized, double-blind clinical and descriptive pharmacokinetic study was carried out at the gynecology departments at Virchow Hospital and Charité Hospital (both university hospitals of Humboldt University, Berlin, Germany) between June 1994 and July 1996 in patients scheduled for elective cesarean delivery under general anesthesia. At the time of the uterine puncture incision, either 0.25 mg or 0.5 mg of nitroglycerin or a physiologic saline solution was administered as an intravenous bolus. Intraoperatively, maternal and neonatal pulse rates and blood pressure were monitored closely. The surgeons estimated reduction in uterine tone and the ease of fetal extraction by means of defined scales. Plasma concentrations of nitroglycerin and its metabolites were measured in maternal venous blood and from umbilical blood. RESULTS: Ninety-seven patients were included in the statistical evaluation of the study; 32 received 0.25 mg of nitroglycerin, 34 received 0.5 mg of nitroglycerin, and 31 received placebo. The evaluation of the surgeons' estimation revealed no significant difference in ease of fetal extraction (statistical power 0.7) and no significant reduction in uterine tone under treatment with both nitroglycerin dosages in comparison with placebo. Only substance-specific maternal side effects were noted. The neonates' conditions were not affected by administration of nitroglycerin. The median fetal-maternal ratio of venous nitroglycerin plasma levels was approximately 1:400 in the 0.25-mg nitroglycerin group and 1:160 in the 0.5-mg nitroglycerin group. Approximately 11-12 times more nitroglycerin was detected in the venous umbilical branch than in the arterial branch. CONCLUSION: Administration of nitroglycerin leads to no clinically relevant easing of fetal extraction, at least not in elective cesarean deliveries after the 34th week of gestation. With regard to pharmacokinetics, the measured median fetal-maternal venous nitroglycerin concentration was 1:400 in the 0.25-mg group and 1:160 in the 0.5-mg group.

Adult↗

Low-dose low-molecular-weight heparin (enoxaparin) is beneficial in lichen planus: a preliminary report.

BACKGROUND: Low-dose heparin devoid of anticoagulant activity inhibits T-lymphocyte heparanase activity, which is crucial in T-cell migration to target tissues. OBJECTIVE: The purpose of this study was to assess the efficacy of low-dose enoxaparin (Clexane), a low-molecular-weight heparin, as monotherapy in lichen planus. METHODS: Included in the study were 10 patients with widespread histopathologically proven lichen planus (LP) associated with intense pruritus of several months' duration. Patients were given 3 mg enoxaparin, subcutaneously once weekly; three patients received four injections, and seven patients received six injections. RESULTS: In nine patients the itch disappeared within 2 weeks. Within 4 to 10 weeks in eight of these patients, there was complete regression of the eruption with residual postinflammatory hyperpigmentation; in one patient, there was marked improvement. In one patient, no effect was observed. Of the four patients who also had oral LP, only one showed improvement. No side effects were observed in any of the patients. CONCLUSION: These findings indicate that enoxaparin may be a simple, effective treatment for cutaneous LP.

Adult↗

Detection of human herpesvirus-8 DNA in Kaposi's sarcomas from iatrogenically immunosuppressed patients.

BACKGROUND: Kaposi's sarcoma (KS) accounts for more than 5% of malignancies in immunosuppressed organ transplant patients (OKS). A new herpesvirus (HHV-8) was identified with high prevalence in biopsy specimens of AIDS-KS, endemic KS, and classic KS and in OKS. KS has also been associated with other underlying diseases in patients treated with corticosteroids, but this subset of KS has been reported to contain HHV-8 in only a few case reports. OBJECTIVE: In this larger study, we determined the prevalence of HHV-8 in seven patients of Jewish origin in whom KS developed during immunosuppressive therapy for different primary diseases (ISKS). METHODS: The study included HHV-8 DNA detection by polymerase chain reaction (PCR) coupled with Southern blot and sequence analysis as well as by in situ hybridization. RESULTS: HHV-8 sequences were detected by PCR with confirmation by Southern blot and sequence analysis in 100% of the ISKS samples. Direct sequencing revealed several previously unknown base changes within the 208 bp region from open reading frame 26 (ORF26[208]) of HHV-8 in ISKS. CONCLUSION: Ours is the largest known study describing the presence of HHV-8 in iatrogenic KS from immunosuppressed nontransplant patients and provides data of previously unknown sequence variations within the ORF26 of HHV-8 DNA.

Aged↗

-A new role for the pediatrician: the prevention of social violence-.

Social violence is a kind of violence which is applied by one individual to another. It is a stake in the field of public health because of an increasing number of children with such behaviors. In addition to environmental factors, the occurrence of abnormal social behavior before 9 years of age seems to precede social violence for the subsequent 20 years of life. One must therefore identify an inadequate attitude towards the parents and/or the teachers, or a poor child's self-esteem and self-respect. These phenomena are based on parental authority, on the ethical development of the child, on his verbalization capacity, on his socialization and his affective development. It is therefore important to stimulate ethical capacities and feelings in the child not only to provide autonomy but also to allow reflexive distinction of language, behavior and judgment, which enable him to understand, consider and respect other individuals.

Affect↗

A 5-year follow-up study of suicide attempts among French adolescents.

PURPOSE: The social, medical, and psychological outcomes of 552 adolescents hospitalized subsequent to an attempted suicide were assessed after an average 5-year follow-up period. METHODS: Evaluation took place by means of mailed questionnaires completed by the adolescents, their parents, and the general practitioner. Using regression analysis, responses were compared with those of a comparison group (n = 273). RESULTS: In the suicidal group, the mean annual mortality rate was seven-fold greater than in the general population of the same age. Education level was lower, and the consumption of alcohol, psychiatric hospitalizations, and contacts with the criminal justice system were more frequent than in the control group. No other variables explored were significantly different between the two groups. CONCLUSIONS: The results of this study carried out on a large sample of French suicidal adolescents tend to confirm results of previous studies performed in other countries. They show that the prognosis for the suicidal adolescent group is less favorable than that of the comparison group.

Adolescent↗

Use of the gel agglutination technique for determination of fetomaternal hemorrhage.

BACKGROUND: Adequate administration of Rh immune globulin requires an accurate determination of the number of D-positive cells in the circulation of D-negative women. Although several tests have been described for the detection of fetomaternal hemorrhage, there is still a need for a rapid, simple, and clinically relevant screening test. STUDY DESIGN AND METHODS: Serial dilutions of a monoclonal anti-D were incubated with stock solutions (0.2 mL) of adult D-negative red cells in the absence or presence of various amounts of fetal D-positive cells (0.1, 0.2, 0.3, 0.4, and 0.5%). After incubation, the supernatants were tested against D-positive red cells by using the new, gel agglutination technique (GAT). After the GAT was adapted to detect D-positive cells at concentrations of > or = 0.2 percent, unselected postpartum samples from D-negative women (n = 420) who delivered D-positive infants were analyzed by both the new test and the Kleihauer-Betke test (KBT). RESULTS: Three of a total of 420 postpartum samples were positive (> or = 0.4% fetal cells), and 406 were negative in both tests. One had 0.5-percent fetal cells in the KBT and gave negative results in the GAT. The latter test was, however, performed after administration of Rh immune globulin. The KBT gave false-positive results in two cases, because of hereditary persistence of hemoglobin F, and the GAT gave a false-positive reaction in one case because of a maternal weak D variant. In the remaining seven cases, the KBT results were only weakly positive (0.2%) and could not be attributed solely to D positive red cells. CONCLUSION: The GAT is suited for routine screening. It provides rapid and specific detection of D-positive red cells at clinically relevant concentrations. The test may (rarely) yield false-negative results due to insufficient administration of Rh immune globulin before testing.

Adult↗

The interest of surgical closure of patent foramen ovale after stroke: a preliminary open study of 8 cases.

The risk of stroke and the risk of recurrent strokes in patients with patent foramen ovale (PFO) need a prevention that still remains a therapeutic problem. There are 4 preventive treatments: anti-agregants, anti-coagulants, transcatheter closure, and surgical closure of PFO. The aim of this study was to demonstrate that surgical closure of PFO is safe and useful for prevention of strokes. Eight patients with stroke and PFO diagnosed by transesophageal echography (TEE) were prospectively selected for surgical closure. It was necessary to be younger than 70 years, not to have another cause of stroke, and to have either recurrent strokes or several ischemic lesions on MRI, isolated for PFO associated with an atrial septal aneurysm, and to have a Valsalva maneuver or cough inducing the stroke. For these reasons, these patients were considered to be an homogenous group with a strong relationship between the PFO and the stroke, and with a high risk of recurrence of stroke. The 8 patients had a direct suture of the PFO with a cardiopulmonary bypass. All patients were followed-up with clinical, MRI and TEE examinations during 12 months after surgery. No surgical complications were observed. After one year, without any anticoagulant treatment, no recurrent stroke or transient ischemic attack, no new ischemic lesions on MRI, nor neuropsychological disturbance were noted. No post-surgical inter-atrial right-to-left shunting was observed. In the absence of controlled studies to guide therapeutic options, our data suggest that surgical closure of PFO in patients with stroke, is safe and efficacious to prevent recurrent stroke without any anticoagulants in the first year of follow-up. Further studies are needed to evaluate the long-term role of surgical closure of PFO as an alternative to prolonged anti-thrombotic treatment.

Adult↗

Detergents and bleaches are sources of chromium contact dermatitis in Israel.

Total chromium levels were determined in 38 detergents and 12 bleaches on the market in Israel (45 locally produced, 5 imported). The samples were analyzed by Zeeman-corrected graphite furnace atomic absorption spectrophotometry. Chromium levels were higher than 5 ppm in 28 (56%) of the 50 products, from 1 to 5 ppm in 16 (32%), and lower than 1 ppm in only 6 (12%). Among the 5 imported products, only 1 had a chromium level below 1 ppm and the other 4 (1 from Germany, 3 from the USA) had high levels. Since a most 90% of the detergents and bleaches examined contained chromium levels higher than 1 ppm, it is concluded that these consumer products may be the cause of the high incidence of chromium sensitivity in Israel.

Anti-Infective Agents, Local↗

Cytomegalovirus activates interferon immediate-early response gene expression and an interferon regulatory factor 3-containing interferon-stimulated response element-binding complex.

Interferon establishes an antiviral state in numerous cell types through the induction of a set of immediate-early response genes. Activation of these genes is mediated by phosphorylation of latent transcription factors of the STAT family. We found that infection of primary foreskin fibroblasts with human cytomegalovirus (HCMV) causes selective transcriptional activation of the alpha/beta-interferon-responsive ISG54 gene. However, no activation or nuclear translocation of STAT proteins was detected. Activation of ISG54 occurs independent of protein synthesis but is prevented by protein tyrosine kinase inhibitors. Further analysis revealed that HCMV infection induced the DNA binding of a novel complex, tentatively called cytomegalovirus-induced interferon-stimulated response element binding factor (CIF). CIF is composed, at least in part, of the recently identified interferon regulatory factor 3 (IRF3), but it does not contain the STAT1 and STAT2 proteins that participate in the formation of interferon-stimulated gene factor 3. IRF3, which has previously been shown to possess no intrinsic transcriptional activation potential, interacts with the transcriptional coactivator CREB binding protein, but not with p300, to form CIF. Activating interferon-stimulated genes without the need for prior synthesis of interferons might provide the host cell with a potential shortcut in the activation of its antiviral defense.

2-Aminopurine↗

The relationship of antiphospholipid antibodies to thromboembolic events in pediatric patients with systemic lupus erythematosus: a cross-sectional study.

The purpose of this study was to evaluate pediatric patients with systemic lupus erythematosus (SLE) to determine 1) the incidence of thrombosis, 2) the incidence of antiphospholipid antibodies, and 3) whether there is an association between the presence of antiphospholipid antibodies and thrombosis. We performed a cross-sectional cohort study in 59 consecutive SLE patients who had been managed at rheumatology clinics in two pediatric hospitals. A history, questionnaire, and chart review were completed by the study nurse blinded to laboratory results. Only the thrombotic events that could be substantiated by review of radiographic tests were accepted. The presence of antiphospholipid antibodies was determined by prospective analysis for a lupus anticoagulant and anticardiolipin antibodies on two separate occasions at least 3 mo apart. Patients were considered to be positive if one or more tests were positive on both occasions. Thirteen thrombotic events occurred in 10 of the 59 patients (17%). Fourteen patients (24%) were classified as positive for lupus anticoagulant, and 19 patients (27%) were classified as positive for anticardiolipin antibodies. A significant relationship between the presence of a lupus anticoagulant and a thrombotic event was shown: odds ratio 28.7 (95% confidence interval 4.03-138.2, p < 0.001). A nonsignificant trend was seen for the presence of an anticardiolipin antibody and a thrombotic event: odds ratio 2.12 (95% confidence interval 0.71-22.8, p=0.08). We conclude that in pediatric patients with SLE: 1) a significant proportion of patients have thrombotic events, 2) a significant proportion of patients have antiphospholipid antibodies, and 3) there is a significant relationship between the presence of a lupus anticoagulant and thrombotic events.

Adolescent↗

Cutaneous ulceration: an unusual sign of methotrexate toxicity--first report in a patient without psoriasis.

OBJECTIVE: To describe a case of skin ulcer related to methotrexate toxicity. CASE SUMMARY: A 67-year-old white man with seronegative arthralgia developed recurrent skin ulcer concurrent with 3-year treatment with methotrexate 5 mg daily. The skin ulcer resolved on discontinuation of methotrexate. DISCUSSION: To the best of our knowledge, this is the first reported case of skin ulcer believed to be induced by methotrexate in a patient without psoriasis. CONCLUSIONS: Skin ulceration should be added to the list of possible toxic adverse effects of methotrexate, not only in psoriatic patients but also in those without psoriasis.

Aged↗