Search PubMed⌕ Search

Biomedical subjects

L Jaber

Publications and source records attributed to L Jaber.

At least 37 records · Page 2Linked to original sources
PubMed1997

Consanguinity and common adult diseases in Israeli Arab communities.

Consanguinity has a deleterious effect with regard to congenital malformation and rare autosomal recessive diseases; however, little information exists on its role in multifactorial common adult morbidity. We investigated the effects of consanguinity on the prevalence of common diseases in adulthood, including diabetes mellitus, myocardial infarction, bronchial asthma, and duodenal ulcer. As part of a larger study investigating the inbreeding coefficient in the Israeli-Arab community, we distributed questionnaires to parents of 4,100 second-grade students in 158 randomly chosen schools. Among the 3,772 responders (92%), 34.8% of the students' fathers and 31% of their mothers were found to be born to consanguineous matings. There was no difference in the prevalence (males, females) between the offspring of consanguineous versus non-consanguineous matings for diabetes mellitus (consanguinity: 4.3%, 1.5% vs. non-consanguinity: 2.9%, 1.6%) myocardial infarction (2.7%, 0.03% vs. 2.3%, 0.03%), bronchial asthma (2.4%, 2.0% vs. 3.7%, 2.3%), or duodenal ulcer (7.0%, 3.0% vs. 7.8%, 2.9%), respectively. The study suggests that even in a population with a high rate of consanguinity, there is no significant increase in the prevalence of these common adult diseases.

Adult↗
PubMed1997

Molecular basis of heat labile hexosaminidase B among Jews and Arabs.

Genotyping individuals for Tay-Sachs disease (TSD) is mainly based on the heat lability of beta-hexosaminidase (Hex) A (alphabeta) and the heat stability of Hex B (betabeta). Mutations in the HEXB gene encoding the beta-subunits of Hex that result in heat-labile Hex B thus may lead to erroneous enzymatic genotyping regarding TSD. Utilizing single strand conformation polymorphism (SSCP) analysis for all 14 exons of HEXB followed by direct sequencing of aberrant fragments, we screened individuals whose Hex B was heat labile. A novel heat labile mutation, previously concluded to exist in the HEXB gene, was identified among Jews and Arabs as 1627 G-->A. One individual with heat labile Hex B (HLB) was negative for this novel mutation and for the known 1514 G-->A HLB mutation, proving that there exists at least one other unidentified HLB mutation. Based on these results, it is advisable to perform DNA tests for 1627 G-->A mutation in suspected HLB individuals.

Arabs↗
PubMed1997

Intramuscular ceftriaxone compared with oral amoxicillin-clavulanate for treatment of acute otitis media in children.

UNLABELLED: Two hundred and fifteen children aged 4 months 6 years with acute otitis media (AOM) were randomized to be treated either by a single i.m. injection of ceftriaxone, 50 mg/kg, with a second dose in the event of unsatisfactory response after 48 h or a history of recurrent AOM (109 patients) or amoxicillin clavulanate 12.5 mg tid (106 patients). The failure rate was similar in children treated by ceftriaxone and amoxicillin clavulanate, 4.6% and 4.7%, respectively (standard error for intergroup difference -2.87%, 95% confidence interval -5.62% to 5.87%). No significant differences between the groups were found in the dynamics of the resolution of the acute symptomatology, otoscopy findings, relapse rate at 30 days or tympanographic evidence of middle ear effusion at the scheduled visits on days 30, 60 and 90. Recurrence of AOM between days 31 and 90 was observed significantly in more children treated with amoxicillin clavulanate than with ceftriaxone--25 out of 84 (29.4%) versus 11 out of 81 (13.6%) (P = 0.012). CONCLUSION: Ceftriaxone injection(s) is as efficient at least as 10-day oral amoxicillin clavulanate for treatment of acute otitis media in children. Although not recommended as routine, ceftriaxone can be considered in the management of acute otitis media under special circumstances, particularly in cases when the ability to tolerate or absorb oral drugs is compromised, in children refusing or unable to take oral therapy or when the compliance is questionable.

Acute Disease↗
PubMed1997

A gene for arthrogryposis multiplex congenita neuropathic type is linked to D5S394 on chromosome 5qter.

Arthrogryposis multiplex congenita (AMC) is a heterogeneous-symptom complex characterized by joint contractures at birth that involve more than one part of the body. We performed a genetic-linkage study of one large Israeli-Arab inbred kindred showing autosomal recessive inheritance of AMC neuropathic type that had been recently investigated by our group. After analysis of approximately 80% of the genome, D5S1456, which showed no increased homozygosity, showed increased genotype sharing in affected individuals. Linkage analysis in all family members revealed linkage between AMC and D5S1456 on chromosome 5qter (maximum LOD score 5.3 at recombination fraction .001). Analysis of additional markers in this region places the gene causing AMC in this family between D5S1456 and D5S498.

Arabs↗
PubMed1997

Modifications of carbohydrate residues and ZP2 and ZP3 glycoproteins in the mouse zona pellucida after fertilization.

Oligosaccharide side chains of zona pellucida (ZP) glycoproteins play a key role in the sperm-egg interaction phenomena during fertilization. In the present study, modifications of the ZP glycoproteins during the fertilization process in the mouse were studied by the lectin-gold technique and immunocytochemistry in conjunction with quantitative analysis. Binding of PNA, RCA I, DSA, LFA, MAA, AAA, and anti-ZP2 and anti-ZP3 antibodies was observed throughout the ZP of both unfertilized and fertilized eggs. However, HPA and BSAIB4 labeling was found only in the inner region of the ZP. After neuraminidase treatment (Neu), HPA showed an affinity for the entire ZP. Labeling by LFA, WGA, MAA, PNA, BSAIB4, and AAA decreased in the ZP of fertilized eggs; however, there was an increase in the binding of RCA I. HPA and Neu-HPA increased only in the inner region of the ZP. Immunoreactivity to antibodies against ZP2 and ZP3 also decreased after fertilization. The present results demonstrate that 1) terminal carbohydrate residues contained in the ZP glycoproteins are modified after fertilization and 2) inner and outer regions of the ZP contain different oligosaccharide side chains.

Animals↗
PubMed1997

Effects of consanguineous marriage on reproductive outcome in an Arab community in Israel.

Intrafamilial marriage is favoured by the Arab community in Israel, almost all of whom live in villages populated by a few (< 20) founding families. A previous study in Taibe, a large Arab village located 30 km from Tel Aviv, showed a significantly high malformation rate among infants of consanguineous parents. The present study examines the reproductive consequences of parental consanguinity in 610 families from the same village, selected retrospectively through infants routinely seen in the local well baby clinic. All mothers were interviewed with regard to previous pregnancy outcomes, including abortions, stillbirths, and neonatal or infant deaths, as well as the degree of consanguinity. In addition, we analysed the anthropometric measurements of the probands. The incidence of infant deaths was significantly higher in the inbred group (p < 0.001). No significant increase in fetal loss between the inbred and outbred groups was observed. There were no differences in anthropometric features, except for a lower birth weight in the consanguineous group (p < 0.035). This study, combined with our previous studies of the same population, indicates a prominent public health problem associated with consanguineous marriage in the Arab community and a need for specific genetic counselling.

Arabs↗
PubMed1997

Speech disorders in Israeli Arab children.

The aim of this work was to study the frequency of speech disorders in Israeli Arab children and its association with parental consanguinity. A questionnaire was sent to the parents of 1,495 Arab children attending kindergarten and the first two grades of the seven primary schools in the town of Taibe. Eight-six percent (1,282 parents) responded. The answers to the questionnaire revealed that 25% of the children reportedly had a speech and language disorder. Of the children identified by their parents as having a speech disorder, 44 were selected randomly for examination by a speech specialist. The disorders noted in this subgroup included errors in articulation (48.0%), poor language (18%), poor voice quality (15.9%); stuttering (13.6%), and other problems (4.5%). Rates of affected children of consanguineous and non-consanguineous marriages were 31% and 22.4%, respectively (p < 0.01). We conclude that speech disorders are an important problem among Israeli Arab schoolchildren. More comprehensive programs are needed to facilitate diagnosis and treatment.

Arabs↗
PubMed1996

Audiovestibular findings in patients with deafness caused by a mitochondrial susceptibility mutation and precipitated by an inherited nuclear mutation or aminoglycosides.

OBJECTIVE: To characterize the audiological and vestibular changes associated with a mitochondrial DNA mutation in an Arab-Israeli family and in other families with mitochondrial predisposition to aminoglycoside-induced hearing loss. DESIGN: Evaluation of audiological (pure tone thresholds, speech reception thresholds, speech discrimination, tympanometry, acoustic reflex thresholds, tone decay, and auditory brain-stem evoked response recording) and vestibular (complete history, physical examination, and 2-channel electronystagmography) systems. In 5 patients, structural evaluation of the inner ear was done by magnetic resonance imaging. PATIENTS: Fifteen members of an Arab-Israeli family, and 1 Chinese woman with the same mitochondrial DNA mutation who experienced hearing loss after short-term exposure to streptomycin. RESULTS: Most of the patients had a profound hearing loss due to cochlear involvement. The hearing loss usually was not accompanied by notable peripheral vestibular dysfunction. In the patient with severe hearing loss after exposure to aminoglycoside, the vestibular function was completely normal. CONCLUSIONS: In most of the Arab-Israeli patients with congenital deafness, the vestibular system function was normal, in contrast to the frequency of vestibular abnormality among deaf children, which was described in the literature. This may be related to genetic predisposition to aminoglycoside-induced deafness.

Adult↗
PubMed1996

Modifications of the lectin binding pattern in the rat zona pellucida after in vivo fertilization.

The zona pellucida (ZP) is an extracellular matrix surrounding the mammalian oocyte. It is involved in the sperm-egg adhesion phenomenon, induces the acrosome reaction, and participates in the late blockage to polyspermy. Thus, during the process of fertilization the cortical reaction is induced and the biochemical and biological properties of the ZP are modified. Some of these changes have been suggested to prevent the polyspermy. However, the mechanisms behind most of these changes are not well understood. Carbohydrate residues of the ZP glycoproteins have been shown to play a key role in the early step of fertilization. In the present study, the changes produced in the terminal oligosaccharide sequences of the rat ZP glycoproteins after in vivo fertilization were investigated by means of lectin-gold cytochemistry. A comparative quantitative analysis of the density of labeling in the ZP before and after fertilization was carried out by automatic counting of gold particles. The ZP of fertilized and unfertilized eggs were labeled by a battery of lectins including PNA, LFA, MAA, AAA, DSA, RCA I, and WGA. For all lectin studied in both fertilized and unfertilized eggs the labeling was preferentially located in the inner region of the ZP. After fertilization, binding of PNA, LFA, MAA, AAA, and DSA decreased in both inner and outer regions of the ZP. Labeling of RCA I-binding sites only decreased in the inner ZP, whereas reactivity to WGA was increased in the inner ZP, whereas reactivity to WGA was increased in the inner area of the ZP. Digestion of the thin-sections with neuraminidase prior to labeling with WGA resulted in a decrease of labeling for WGA binding sites. However, the labeling density of WGA binding sites was similar in both unfertilized and fertilized eggs upon treatment with neuraminidase. The present results demonstrate that the oligosaccharide chains contained in the rat ZP are modified after fertilization of the oocyte. Cortical granules of the oocytes might be involved in these modifications by two mechanisms: 1) by hydrolysis of terminal carbohydrate residues of ZP glycoproteins by specific glycosidases contained in the granules; and 2) by addition of new glycoproteins to the ZP after the exocytosis of the cortical granules (cortical reaction).

Animals↗
PubMed1996

Demographic characteristics of the Israeli Arab community in connection with consanguinity.

In a previous nationwide survey of the Israeli Arab community we showed that 44% of all marriages are consanguineous. Further analysis of the data from this previous survey was undertaken, and we defined six demographic characteristics that may be associated with consanguinity or non-consanguinity in the marriages. Of these, we found a significant correlation (P <0.001) with religion (for Moslems, odds ratio 1.7), consanguinity in parents' marriages, and the respondent's attitude towards consanguineous marriage. The educational level achieved was not a major factor in the type of marriage chosen. These findings should enable us to plan specifically designed educational and counseling programs with a view to reducing the overall incidence of consanguineous marriage.

Adult↗
PubMed1995

Arthrogryposis multiplex congenita in an Arab kindred: update.

We have restudied the genetic and clinical characteristics of a large Arab kindred previously reported in 1970 by Lebenthal et al. [Pediatrics 46:891-899]. At total of 40 affected individuals was identified; all, except one, were products of 22 different consanguineous matings between the parents. The syndrome, which is present at birth, is expressed mainly by flexion contractures at the knees and elbows, with muscle hypotrophy/weakness around the involved joints. Five of the 6 individuals who were originally reported as having congenital and lethal heart defects were limited to one sibship. None of the new cases had heart defect or any associated malformation. Neurologic examination and electrophysiological studies demonstrated a neuropathic (non-myopathic) type of arthrogryposis. This is an autosomal recessive trait with wide variability in expression and possibly incomplete penetrance in the females. Because of the high consanguinity rate, it allows the use of homozygosity linkage studies to map the gene for this disorder.

Arthrogryposis↗
PubMed1994

Consanguineous matings in an Israeli-Arab community.

OBJECTIVE: To determine the frequency of consanguineous marriages and the inbreeding coefficient in Israeli Arabs. DESIGN: Cohort survey. SETTING: General community in 70 settlements in Israel. PARTICIPANTS: Nine thousand three hundred Israeli-Arab students in the second grade were sent questionnaires to be filled out by their fathers, with 8521 completed questionnaires returned. INTERVENTIONS: None. MEASUREMENTS/MAIN RESULTS: Of the 8521 completed questionnaires, 1156 (14%) were from urban areas, 2267 (27%) were from suburban areas, and 5098 (60%) were from rural areas. The prevalence of consanguineous matings in the studied group was 44.3%, with a mean inbreeding coefficient of .0192. This prevalence is high and was highest in the rural areas. Marriages between first cousins occurred more often than marriages between other relatives in all locations. CONCLUSION: The frequency of consanguineous marriages is quite high among Israeli Arabs, approaching 50%.

Consanguinity↗
PubMed1994

High incidence of central nervous system malformations associated with marked parental consanguinity in an Israeli Arab community.

It is common among Israeli Arabs who live in villages to prefer consanguineous marriages, particularly among first cousins. In addition, such villages are populated by a few (< 20) original families, and inter-family/inter-village marriages are infrequent. The purpose of this study was to examine the incidence of congenital malformation of the central nervous system associated with such "consanguinity" in Taibe, a large Arab village, 30 km from Tel Aviv. Six hundred and ten families were prospectively ascertained through infants who were routinely seen in the local "Well Baby Clinics". A significant increase in the incidence of major malformations was noted in relation to the closeness of the parental relationship. For the index cases group, the prevalence of individuals with major malformations was 5.8% in the product of inter-village marriages, 8.3% in the intra-village non-related matings, 15.1% in the distant consanguineous group, and up to 15.8% in the progeny of first-cousin marriages (P < 0.001). Malformations of the central nervous system consisted of 1/3 to 1/2 of the total malformations in the consanguineous group versus less than 1/5 in the non-consanguineous groups. The study demonstrates a marked high rate of consanguineous marriages, the effect of which leads to a marked increase in major malformations and especially those of the central nervous system. This requires a unique genetic counseling approach.

Adult↗
PubMed1994

Hb Taybe (alpha 38 or 39 THR deleted): an alpha-globin defect, silent in the heterozygous state and producing severe hemolytic anemia in the homozygous.

Several alpha-chain hemoglobin variants have been described as responsible, in homozygous or compound heterozygous patients, for a chronic hemolytic disease that overlaps thalassemia and Heinz bodies hemolytic anemia phenotypes. These variants are present in trace amounts together with some Hb H in the lysate of the patients. In the asymptomatic heterozygous carriers, they are usually not detected by electrophoretic methods. Hb Taybe is an example of such an unstable and thalassemic alpha-hemoglobin variant. This hemoglobin was observed in a young Israeli Arab woman having suffered since birth from a severe and highly regenerative hemolytic anemia for which she was splenectomized at age sixteen. The structural abnormality was characterized by protein chemistry as the deletion of a threonine residue at position alpha 38 or 39 and assigned to the alpha 1 gene by selective DNA sequencing. This structural modification is localized in helix C, which is a highly conserved 3(10) helix participating in the alpha 1 beta 2 contact and close to the alpha 1 beta 1 interface. The propositus and two siblings, who were also anemic, were found to be homozygous for the molecular defect, although the abnormal Hb was not detected in the latters. Consanguinity in this family demonstrated the threshold effect in the clinical manifestations of such alpha-gene disorders since heterozygotes were clinically and biologically normal.

Adult↗
PubMed1993

A form of sensorineural deafness is determined by a mitochondrial and an autosomal locus: evidence from pedigree segregation analysis.

We have previously reported a large Israeli-Arab pedigree with sensorineural deafness possibly determined simultaneously by two loci--one mitochondrial, and one autosomal recessive. This was analyzed by extending classic segregation analysis methods to the many nuclear families derived from the maternal line pedigree. Here we expand this pedigree and extend our analysis by using the regressive models for segregation analysis on the entire pedigree. The corresponding REGD computer program was utilized and the marrying-in males' and paternal line members' affection statuses were assigned as unknown to accommodate the exclusive maternal transmission pattern. For the autosomal locus, a simple autosomal recessive (q = 0.52) model with a nearly complete penetrance (0.93) was found to be the best-fitting model. Equally importantly, we were also able to use the power of the regressive models to test the hypothesis of mitochondrial heteroplasmy as an alternative for the proposed autosomal locus. We found no evidence for the heteroplasmy hypothesis as an explanation for the incomplete maternal transmission of deafness in this pedigree. Thus, even if the mitochondrial mutation occurred in a heteroplasmic distribution in the family members, this could not explain the familial aggregation in this pedigree, and an autosomal recessive locus is still required. These results provide further support for the concept that the sensorineural deafness occurring in this large Israeli-Arab pedigree results from simultaneous involvement of two genes at two different loci, one mitochondrial and likely homoplasmic, and the other autosomal and recessive.

Computer Simulation↗
PubMed1993

Meconium aspiration and otitis media in children.

Meconium-stained amniotic fluid was recently reported to be significantly correlated with a higher incidence of otitis media during infancy. In order to verify this connection, a case-control study was performed on 71 pairs of infants, with and without meconium aspiration, matched for gestational age, birth weight and sex. Data were collected by questionnaire or telephone, the response rate being 88.7%. No significant difference in incidence of otitis media between the two groups was observed. This study demonstrated that newborns with meconium aspiration are not at greater risk for otitis media in the 1st year of life.

Case-Control Studies↗
PubMed1993

Mitochondrial ribosomal RNA mutation associated with both antibiotic-induced and non-syndromic deafness.

Maternally transmitted non-syndromic deafness was described recently both in pedigrees with susceptibility to aminoglycoside ototoxicity and in a large Arab-Israeli pedigree. Because of the known action of aminoglycosides on bacterial ribosomes, we analysed the sequence of the mitochondrial rRNA genes of three unrelated patients with familial aminoglycoside-induced deafness. We also sequenced the complete mitochondrial genome of the Arab-Israeli pedigree. All four families shared a nucleotide 1555 A to G substitution in the 12S rRNA gene, a site implicated in aminoglycoside activity. Our study offers the first description of a mitochondrial rRNA mutation leading to disease, the first cases of non-syndromic deafness caused by a mitochondrial DNA mutation and the first molecular genetic study of antibiotic-induced ototoxicity.

Aminoglycosides↗