Biomedical subjects

L Lazar

Publications and source records attributed to L Lazar.

At least 19 recordsLinked to original sources

PubMed2007

Heat-shock protein peptide DiaPep277 treatment in children with newly diagnosed type 1 diabetes: a randomised, double-blind phase II study.

BACKGROUND: Type 1 diabetes mellitus (T1DM) is a T-cell-mediated autoimmune disease that leads to the destruction of insulin-producing beta cells. Treatment with DiaPep277, a peptide derived from heat-shock protein 60 (hsp60), has been found to slow the deterioration of beta-cell function after clinical onset of diabetes in NOD mice and human adults. Our aim was to evaluate the efficacy and safety of DiaPep277 treatment in attenuating beta-cell destruction in children with recent-onset T1DM. METHODS: A prospective, randomized, double-blind, phase II design was used. The sample included 30 children (19 males) aged 7-14 years who had been diagnosed with T1DM from 53 to 116 days previously, and had basal C-peptide concentrations above 0.1 nmol/L. The children were randomized to receive subcutaneous injections of 1 mg DiaPep277 (15 patients) or 40 mg mannitol (placebo) at entry and at 1, 6, and 12 months. The duration of follow-up was 18 months. The groups were compared for stimulated C-peptide level, exogenous insulin dose, and HbA1c concentration. RESULTS: C-peptide levels similarly decreased over time in the DiaPep277- and placebo-treated patients. There was no significant difference in insulin dose or HbA1c concentration between the groups at any time point. No serious drug-related adverse effects were recorded throughout the study period. CONCLUSIONS: One-year treatment with DiaPep277 at a dosage of 1 mg is safe for use and well tolerated in children with recent-onset T1DM. However, it appears to have no beneficial effect in preserving beta-cell function or improving metabolic control.

Adolescent↗

PubMed2006

A new mutation in the growth hormone-releasing hormone receptor gene in two Israeli Arab families.

BACKGROUND: Mutations in the GHRH receptor gene (GHRH-R) are emerging as a common cause of familial isolated GH deficiency (IGHD). DESIGN: We searched for GHRH-R mutations in 10 patients with IGHD of Israeli-Arab origin, belonging to two highly consanguineous families. METHODS: Analysis of the 13 coding exons, the intron-exon boundaries, and the proximal promoter of the GHRH-R was performed by denaturing gradient gel electrophoresis. Abnormally migrating bands were sequenced. The newly found mutation was inserted into GHRH-R cDNA. Wild type and mutant receptor were expressed in Chinese hamster ovary (CHO) cells, and the cAMP response to GHRH was measured. RESULTS: All patients were homozygous for a novel GHRH-R missense mutation in exon 11 that replaces arginine with cysteine (R357C). Functional assay demonstrated complete inactivity of the mutant receptor in vitro. The prevalence of the mutant allele in the Israeli-Arab population was found to be 2%. All the patients had low but detectable GH reserve, proportionate short stature, and growth retardation since early childhood, with good growth response to GH treatment. Magnetic resonance imaging, performed in 3 patients, revealed a normal sized anterior pituitary in one patient evaluated at early childhood, and a borderline hypoplastic gland in the 2 patients evaluated at puberty. CONCLUSIONS: We describe a novel missense mutation in the GHRH-R. The high incidence of the mutant allele in Israeli Arabs suggests that the mutation may be a common cause of familial IGHD in this population.

Adolescent↗

PubMed2005

Effect of sex hormone administration on circulating ghrelin levels in peripubertal children.

BACKGROUND: Ghrelin levels gradually decrease throughout childhood and with advancing pubertal stage. The change during puberty is more pronounced in boys than girls. OBJECTIVE: The objective of the study was to investigate whether the pubertal drop in ghrelin secretion is modified by the increase in sex hormones. PATIENTS AND METHODS: Ghrelin levels were measured in 34 short peripubertal children (17 boys and 17 girls) aged 8-12.5 yr before and after sex hormone priming for GH stimulation testing. RESULTS: In boys, priming with testosterone increased testosterone to pubertal levels (23.7 +/- 7.1 nmol/liter), which in turn induced a marked decrease in ghrelin (from 1615.8 +/- 418.6 to 1390.0 +/- 352.0 pg/ml) and leptin (from 8.0 +/- 4.5 to 5.8 +/- 3.2 ng/ml) and an increase in IGF-I (from 162.7 +/- 52.8 to 291.1 +/- 101.6 ng/ml) (P < 0.001 for all parameters). In girls, priming with estrogen led to a supraphysiological increase in estradiol levels (1313.8 +/- 438.0 pmol/liter), which had no effect on ghrelin, leptin, or IGF-I. There was no correlation between ghrelin levels and levels of sex hormones, leptin, or body mass index in either boys or girls. CONCLUSIONS: A pharmacological increase in sex hormones is associated with a marked decline in circulating levels of ghrelin in boys but not girls. Additional longitudinal studies through puberty are needed to elucidate the physiological interaction between sex hormones and ghrelin.

Body Height↗

PubMed2005

Three novel mutations in POU1F1 in Israeli patients with combined pituitary hormone deficiency.

BACKGROUND: POU1F1, a pituitary-specific transcription factor of the class 1 POU family, is crucial for the development and differentiation of the anterior pituitary gland. Mutations in the POU1F1 gene have been shown to be responsible for a syndrome of combined pituitary hormone deficiency (CPHD), including prolactin, growth hormone and thyroid-stimulating hormone deficiencies. METHODS: Five patients with CPHD from three families were evaluated. The clinical and biochemical data were taken from the medical records. DNA was analyzed by polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), and sequencing. RESULTS: Molecular analysis yielded three novel mutations in POU1F1: W193X, Q242R (-2 bp), and F262L. CONCLUSIONS: Three novel POU1F1 mutations were detected in Israeli patients with CPHD. Two of them, a W193X missense mutation and a deletion of two adenine bases at position 242Q, may lead to the production of a truncated protein that lacks the entire POU homeodomain or part of it, respectively. The third mutation, F262L, resides in the POU homeodomain and hence might change the activity of the protein.

Arginine↗

PubMed2004

Prepubertal gynaecomastia: aetiology, course and outcome.

BACKGROUND: Palpable and measurable glandular breast tissue is a rare finding in prepubertal boys and warrants thorough evaluation to rule out an underlying pathology. OBJECTIVE: To characterize the course and outcome of prepubertal gynaecomastia, examine its effect on puberty, and try to identify its underlying cause. PATIENTS AND METHODS: Twenty-nine out of 581 (5%) boys referred to our clinic for evaluation of gynaecomastia between 1980 and 2000 were prepubertal at diagnosis. Data on age at appearance of gynaecomastia, general and endocrine evaluation, course of growth and puberty, and treatment were collected from the medical files. RESULTS: Prepubertal gynaecomastia was diagnosed at mean age of 8.9 +/- 2.2 years. In 27 of the 29 boys (93.2%) no underlying cause was identified. The remaining two boys (6.8%) had hyperaromatase syndrome. Nine boys (31%) were obese. Spontaneous resolution was recorded in six boys (20.5%), no change in 15 (52%), and further breast enlargement in eight (including the two with hyperaromatase syndrome) (27.5%). Accelerated growth and bone maturation rates were noted only in the two boys with hyperaromatase syndrome. Pubertal onset was documented in 13 boys at 11.8 +/- 1.1 years. CONCLUSIONS: According to our large single tertiary care centre experience, 5% of boys referred for evaluation of gynaecomastia were prepubertal. The development of gynaecomastia was the only abnormality and was not associated with other pubertal signs or accelerated growth rate. In most cases, the gynaecomastia was idiopathic. Further prospective studies are needed to evaluate the pathophysiological mechanisms responsible for this phenomenon.

Aromatase↗

PubMed2003

PROP-1 gene mutation (R120C) causing combined pituitary hormone deficiencies with variable clinical course in eight siblings of one Jewish Moroccan family.

BACKGROUND: PROP-1 gene mutations have been described in patients with combined pituitary hormone deficiencies (CPHD). METHODS: Clinical follow-up and molecular analysis of the PROP-1 gene were performed in 4 affected sisters of one consanguineous family, in whom 8 members had CPHD. RESULTS: The 4 sisters were homozygous for the same R120C mutation. Growth hormone and thyroid-stimulating hormone deficiencies were diagnosed concomitantly in all subjects, but at different ages (5.5-10.8 years). All 8 subjects exhibited complete gonadotropin deficiency with failure of spontaneous sexual maturation. Adrenocorticotropic hormone deficiency developed in only 2 sisters in the 3rd and 4th decades of life. CONCLUSIONS: The CPHD in this family, caused by an R120C mutation, was characterized by clinical phenotypic variability in terms of the severity of hormonal deficiencies and the time of their development. Identifying the mutation does not predict the clinical course. Therefore, continuous follow-up with repeated endocrine evaluations is mandatory to provide proper hormone substitution therapy.

Adult↗

PubMed2003

Craniopharyngioma: presentation and endocrine sequelae in 36 children.

We studied the clinical presentation by age of 36 children with craniopharyngioma, and outcome by height and body mass index (BMI). Presenting symptoms included headache (51.4%), vomiting (31%), visual disturbances (22.9%), polyuria and/or polydipsia (17.1%), delayed puberty (19.4%), short stature (13.8%), and precocious puberty (2.7%). Growth deceleration was overlooked, as was diabetes insipidus (actual rate, 52% for both). Delayed puberty was observed in all patients of appropriate age. Mean height standard deviation score (SDS) at admission was significantly lower than mean target height SDS (p = 0.004), while mean final height SDS was similar (p = 0.14). BMI SDS at last follow-up was similar to mean parental BMI SDS. We conclude that although endocrinopathies are present in most patients with craniopharyngioma, they are rarely the reason for referral. While affected prepubertal children have non-endocrine complaints, most adolescents are referred because of delayed puberty. Diabetes insipidus may be more prevalent in craniopharyngioma than previously reported. When patients with hypothalamic obesity are excluded, mean BMI SDS remains within normal range and is influenced mostly by parental BMI SDS.

Adolescent↗

PubMed2002

Quadriceps paresis in pediatric groin surgery.

A total of 2,624 groin operations were performed in 2,202 infants and children aged 6 months-14 years during the last 4.5 years. Preventive analgesia was used in all operations, and included ilioinguinal and iliohypogastric nerve block combined with inguinal canal infiltration. In 6 patients transient postoperative quadriceps muscle paresis (QMP) was noted. They required bed rest and monitoring for a few hours, and complete spontaneous recovery was noted in all cases. The aim of this study was to examine the incidence of transient QMP following regional nerve block and to discuss models of possible prevention.

Adolescent↗

PubMed2002

The distal pouch in esophageal atresia -- to dissect or not to dissect, that is the question.

Long-gap esophageal atresia remains a difficult problem for the pediatric surgeon and reconstruction using the native esophagus is considered to be superior to any interposition procedure. Because of esophageal segmental blood supply and vascular vulnerability of the distal esophageal pouch in the short term and its motility disorder in the long term, surgeons are reluctant to perform extensive esophageal dissection. However, ascending and descending branches of esophageal vessels converge along the anterolateral and posterolateral aspects of the esophagus. This arrangement allows for dissection and mobilization of the distal pouch without necessarily causing vascular impairment. Extensive dissection of the distal pouch was advocated by Robert Gross over fifty years ago. More recently, circular myotomy of the distal pouch has been performed. However, manometric studies showed that prior to surgical repair, peristalsis of the upper and lower esophageal pouch was synchronized, while after surgery this coordination was clearly defective. Furthermore, in the adriamycin-induced rat model, inherent abnormalities in the course and branching pattern of the vagus nerves in the lower esophagus have been demonstrated. Significant abnormalities of the intramural nervous components involving both the excitatory and inhibitory nerves, and elevated levels of S100 and galanin in the lower esophageal pouch could explain an inborn motility disorder. The selective injury of minor vagal branches in experimental animals also alters esophageal peristalsis. In conclusion, given that the native esophagus is still considered the best alternative for reconstruction of esophageal atresia, when indicated, gentle but extensive dissection of the lower esophageal pouch seems to be preferable, keeping in mind the possibility of vascular compromise and the inevitability of motility disfunction.

Digestive System Surgical Procedures↗

PubMed2002

Gonadotropin-suppressive therapy in girls with early and fast puberty affects the pace of puberty but not total pubertal growth or final height.

Early and fast puberty (EFP) in girls, defined as pubertal onset at age 8-9 yr, with an accelerated course, may cause compromised final height (FHt) and psychosocial distress. Treatment with a gonadotropin-suppressive agent is controversial, because the improvement in FHt is equivocal and there may be risk of obesity. We analyzed the data of 126 girls with EFP: 63 treated with GnRH analog (GnRHA) since Tanner stage 3, for 2-4 yr; and 63 untreated. Age at onset of puberty; accelerated time of transition from Tanner stage 2 to 3 (<1.3 yr); and clinical, hormonal and sonographic findings were similar in the 2 groups. The girls given GnRHA treatment had a significantly prolonged pubertal course, compared with the accelerated course in the untreated girls (4.7 +/- 0.4 vs. 2.45 +/- 0.4 yr, P < 0.001). After therapy, they reached Tanner stages 4 and 5 and FHt at a significantly older age than the untreated group (P < 0.001), and their menarche was delayed (12.8 +/- 0.6 vs. 10.8 +/- 0.5 yr, P < 0.001). However, the different pace of puberty in the 2 groups did not change the total pubertal growth and the bone maturation rate. The Ht gain from Tanner stage 3 to 4 (10.4 +/- 2.7 vs. 11.2 +/- 3.1 cm) and from Tanner stage 4 to FHt (8.2 +/- 2.7 vs. 8.8 +/- 3.6 cm) was similar in the treated and untreated girls, as were absolute Ht and bone age at each pubertal stage. The weight gain of the treated girls was more pronounced during treatment (P = 0.0016), but it was arrested after discontinuation of therapy; and by the time FHt was reached, the body mass index was similar in the 2 groups. The treated and untreated girls achieved a similar mean FHt, which was not significantly different from their respective mean target Ht (THt). Individual analysis revealed that 70% of the treated girls and 67% of the untreated girls attained their THt range (THt +/- 0.5 SD) or surpassed it. In conclusion, treatment with GnRHA affected only the pace of EFP. The similar Ht gain and bone maturation rate at each pubertal stage in the treated and untreated girls may suggest that the total pubertal growth is not dependent on pubertal duration and pace and is probably determined already at the onset of the normal pubertal development. The treatment did not compromise the FHt and did not cause long-lasting obesity. Therefore, GnRHA therapy may be suggested for use in girls who have psychosocial difficulties in coping with EFP.

Body Height↗

PubMed2002

A novel mutation in PIT-1: phenotypic variability in familial combined pituitary hormone deficiencies.

Mutations in PIT-1 have been described in several cases of familial combined pituitary hormone deficiencies. This study describes a novel PIT-1 mutation that was found in two siblings of a highly consanguineous family of Israeli-Arab origin. The missense mutation (G688A) causes a lysine (K) to glutamic acid (E) substitution at codon 230. This codon resides in the first helix of the POU-homeodomain, which is directly involved in DNA binding. This amino acid is conserved in most homeodomain proteins, suggesting that the substitution disrupts the DNA-binding activity of the mutant protein. Two main observations are described: 1. The clinical presentation of the mutation involves intrauterine growth retardation. 2. One sibling had full deficency of growth hormone and thyroid stimulating hormone, whereas the other had only growth hormone deficiency. This is, to the best of our knowledge, a unique expression of a novel PIT-1 mutation.

DNA↗

PubMed2001

Congenital short-bowel and malrotation: clinical presentation and outcome of six affected offspring in three related families.

Newborns with congenital short small bowel associated with malrotation and intestinal dysmotility have a uniformly bad prognosis. However, few long-term survivors have been reported, suggesting that the disorder is not invariably fatal. The majority of cases previously reported were familial. We report on six affected siblings in three related families. The aim of this report is to assess the mode of inheritance, the expression of this disorder, and to point to the correlation between the onset of gastrointestinal symptoms and the outcome.

Adolescent↗

PubMed2001

Abdominal injuries caused by bicycle handlebars.

OBJECTIVE: To find out whether the increase in the number of children admitted with injuries from mountain bicycle handlebars is attributed to recent changes in the design of children's bicycles. DESIGN: Retrospective study. SETTING: Teaching general hospital, Israel. SUBJECTS: 76 children who presented with abdominal injuries caused by bicycle handlebars. RESULTS: In 12 of the 76 children, there was an imprint of the handlebar edge on the hypochondrium. The most common injuries were isolated ruptures of spleen or liver, (14 and 11 patients, respectively). Five of the 25 patients were operated on and the rest treated conservatively. CONCLUSIONS: Children with an imprint or bruise made by the handlebar edge on the abdominal wall, or who give a clear history of injuries by a bicycle handlebar should be treated with great care. BMX handlebars are relatively high (for young riders) and wide; they also turn freely and are therefore in direct line with the upper abdomen. Prohibiting the use of bicycles with unpadded handlebars may prevent some of these intra-abdominal injuries.

Abdominal Injuries↗

PubMed2001

Volvulus of the stomach in childhood: the spectrum of the disease.

INTRODUCTION: During a 5-year time frame, five cases of symptomatic gastric volvulus were diagnosed and treated in our department. Four presented with the acute form of gastric volvulus and underwent emergency surgery. The fifth suffered the chronic variant of the syndrome and was benefited by nonoperative management. The cases serve to remind emergency physicians of the spectrum of gastric volvulus. The report supplements the sparse clinical description in the emergency literature. RESULTS: In the operated patients, there were no postoperative complications. The outcome, to the time of publication, has been good in every instance. The history, etiology, presentation, and treatment of the disease are discussed in detail. CONCLUSIONS: Not infrequently, gastric volvulus in children fails to exhibit the full gamut of signs and symptoms such as abdominal distension, vomiting, pain, and retching. For this, as well as for other stated reasons, symptomatic gastric volvulus in infancy and childhood may not be as rare as is commonly assumed.

Acute Disease↗

PubMed2001

Sexual precocity in boys: accelerated versus slowly progressive puberty gonadotropin-suppressive therapy and final height.

The indication for GnRH analog treatment in boys with central sexual precocity is based mainly on the age of onset of puberty. Our aim was to determine whether the rate of pubertal progression should also be taken into consideration. Included in the study were 81 boys with central sexual precocity: 27 with true precocious puberty (onset at <9 yr) and 54 with early puberty (onset at 9-10.5 yr). At the time of analysis, all had completed puberty, and 66 (22 central precocious puberty, 44 early puberty) had achieved final height. Progression of puberty (Tanner stage 2 to 3) was accelerated (0.5-1.32 yr) in 42 boys (16 central precocious puberty, 26 early puberty) and slow (1.7-2.9 yr) in 39 (11 central precocious puberty, 28 early puberty). The boys with accelerated puberty had significantly elevated T levels (central precocious puberty and early puberty, P < 0.001), faster growth rate (change in height SD score/duration: central precocious puberty, P < 0.05; early puberty, P < 0.01), and faster bone maturation rate (change in bone age/duration: central precocious puberty, P < 0.05; early puberty, P < 0.001). All 42 boys with accelerated puberty were treated with GnRH analog for 2.3-4.2 yr; the duration to completion of puberty and the height gain after therapy was discontinued were similar for the boys with central precocious puberty and early puberty. The 39 boys with slow puberty received no treatment and had a prolonged course of puberty (central precocious puberty, 5.05 +/- 0.3 yr; early puberty, 4.72 +/- 0.77 yr; average normal, 3.5 yr). The final height achieved in the 35 (11 central precocious puberty, 24 early puberty) untreated boys was within the range of their respective target height. The 31 (11 central precocious puberty, 20 early puberty) treated boys also achieved their genetic target height. Predictions based on the Bayley-Pinneau method at Tanner stage 3 for all boys and at discontinuation of therapy for treated boys overestimated the achieved final height (P < 0.001). In conclusion, boys with sexual precocity, whether central precocious puberty or early puberty, may have either accelerated or slow pubertal development. The decision to institute suppressive therapy should be based also on the rate of pubertal progression. Treatment should be offered only to those (either central precocious puberty or early puberty) with accelerated growth and bone maturation rates and rapid increase in T levels. Suppression therapy apparently converts accelerated puberty into nonsustained slow puberty and probably prevents compromised final height.

Body Height↗

PubMed2001

Ultrasound features of spermatic cord hydrocele in children.

The aim was to evaluate the value of ultrasound diagnosis of spermatic cord hydrocele as a cause of inguinal swelling or mass in children. Clinical and ultrasound (US) findings and surgical procedures of 27 children with spermatic cord hydrocele were reviewed. All children, except one, were referred for US because of suspected inguinal hernia, hydrocele or inguinal mass. In one child, the US examination was performed to confirm the diagnosis of a spermatic cord hydrocele. An encysted hydrocele was diagnosed in 24 out of 27 cases, whereas a funicular type of spermatic cord hydrocele was found in the remaining 3 cases. Internal septa were seen within the fluid mass in four patients. 23 children underwent surgical exploration that confirmed the US diagnosis. Three children with encysted-type hydrocele were only followed clinically and by US, and one was lost from follow-up. US examination is a very sensitive and accurate method for diagnosis of this entity and for exclusion of other lesions in this region.

Adolescent↗

PubMed2000

The vitrification of in vitro fertilized cow blastocysts by the open pulled straw method.

In 6 replicates, a total of 450 immature oocytes recovered from 144 slaughterhouse-derived bovine ovaries were matured and fertilized in vitro, then cultured for 7 to 9 d on a granulosa cell monolayer in tissue culture medium 199 (TCM-199) supplemented with fetal calf serum. Of 126 blastocysts (28% of oocytes cultured), 117 (26% of oocytes cultured) were vitrified in Hepes/bicarbonate-buffered TCM-199 medium and 20% fetal calf serum, with ethylene glycol and dimethylsulfoxid as the cryoprotectants. After thawing in 1.2 mL holding medium with 0.25-M sucrose and after 1 min in holding medium with 0.15-M sucrose, blastocysts were cultivated in vitro for 24 h. The re-expansion rate of blastocysts was 69.2% (81 blastocysts), and 39.5% (32 blastocysts) were hatched. Re-expansion and hatching rates differed between the blastocysts vitrified on 7 and 8+9 days (74.6% and 46% vs. 62% and 29%, respectively). After transfer to recipient cows, 3 out of 6 were diagnosed by ultrasonography as pregnant. Three calves were born from 18 transferred embryos (16.7%). The open pulled straw (OPS) method seems to be a convenient, simple and effective method for cryopreservation of 7 to 9 d bovine embryos.

Animals↗

PubMed2000

Thyrotoxicosis in prepubertal children compared with pubertal and postpubertal patients.

The course of Graves' thyrotoxicosis in 7 prepubertal children (6.4+/-2.4 yr) was compared with that in 21 pubertal (12.5+/-1.1 yr) and 12 postpubertal (16.2+/-0.84 yr) patients. In the prepubertal group the main complaints were weight loss and frequent bowel movements (86%), whereas typical symptoms (irritability, palpitations, heat intolerance, and neck lump) occurred significantly less often (P < 0.01). The most prominent manifestation at diagnosis was accelerated growth and bone maturation: their height SD score was significantly greater than that of the pubertal and postpubertal patients (2.6+/-0.7 us. 0.15+/-0.65 and 0.15+/-0.9, respectively, P < 0.001), and their bone age to chronological age ratio was 1.39+/-0.35 compared with 0.98+/-0.06 in the pubertal children (P = 0.02). T3 levels were also significantly higher than in the other two groups (9.9+/-2.9 nmol/L vs. 6.32+/-1.9 nmol/L and 6.02+/-2.0 nmol/L, P = 0.01). All patients were initially prescribed antithyroid drugs (ATDs). Overall, adverse reactions to ATDs occurred in 35%, with a higher rate among the prepubertal children (71%) than the pubertal (28%) and postpubertal (25%) patients (P = 0.08). Major adverse reactions were noted in two children, both prepubertal. Remission was achieved in 10 patients (28%). Although the rate of remission did not differ among the three groups, time to remission tended to be longer in the prepubertal children (P = 0.09). In conclusion, thyrotoxicosis has an atypical presentation and more severe course in prepubertal children. Considering their adverse reactions to ATD, overall low remission rate, and long period to remission, definitive treatment should be considered earlier in this age group.

Adolescent↗