PubMed Health⌕ Search

Biomedical subjects

E Baskin

Publications and source records attributed to E Baskin.

At least 19 recordsLinked to original sources

Quantization of 2D hole gas in conductive hydrogenated diamond surfaces observed by electron field emission.

Discrete jumps are observed in the emitted current density (J) versus extraction electric field (E) curves in electron field emission measurements from a conductive, hydrogen-terminated air-exposed diamond surface. These jumps are well reproduced by computations based on the assumption that a 2D nanoscale quantum system with discrete energy levels exists in the diamond near-surface layer. The present results confirm the formation of well-defined quantum states of holes in the 2D surface layer present on hydrogenated air-exposed diamond surfaces.

Journal Article↗

[Hemicentral retinal artery occlusion associated with moyamoya syndrome].

Moyamoya syndrome is a rare cerebrovascular disorder characterized by bilateral progressive supraclinoidal stenosis or occlusion of the internal carotid artery and development of collateral vessels in the lenticulostriate region. The syndrome manifests itself in association with another disease or other clinical symptoms. We present the case of a 12-year-old girl with hemicentral retinal artery occlusion due to moyamoya syndrome associated with clinical and laboratory findings of presumed systemic lupus erythematosus.

Child↗

Renal transplantation in children.

INTRODUCTION: Various immunological, metabolic, and technical factors render pediatric recipients with end-stage renal disease unique from their adult counterparts. In addition, the potential for complications after renal transplantation is far greater in children than in adults. In this study, we retrospectively analyzed 83 pediatric recipients who underwent kidney transplantation at our institution from 1975 to 2004. MATERIALS AND METHODS: From November 1975 to December 2004, 1523 renal transplantations were performed at our institution with 56 procedures in 83 pediatric patients (44 boys and 39 girls; age range, 7 to 17 years; mean age, 14.9 +/- 2.2 years). RESULTS: Long-term follow-up revealed the following morbidities in 14 (16.3%) recipients: lymphocele in 7 (8.1%) patients, perirenal hematoma in 2 (2.3%), graft renal artery stenosis in 2 (2.3%), ureteral stenosis in 2 (2.3%), and ureteral anastomotic leak in 1 (1.2%). Six (7.2%) recipients with a functioning graft died during follow-up (five deaths were infection related, and the cause of one death was unknown). Five grafts failed (four for immunological reasons and one as a result of recurrent disease). The 1-, 3-, 5-year patient and graft survival rates were 98%, 93%, 92% and 91%, 78%, 67% for living related transplantations versus 98%, 91%, 90% and 92%, 76%, 65% for cadaveric transplantations, respectively. DISCUSSION: Better outcomes for renal transplantation in children may be obtained by strict adherence to precise surgical techniques, better immunosuppressive management, and early diagnosis/effective treatment of complications.

Adolescent↗

Negative superdiffusion due to inhomogeneous convection.

Fractional transport of particles on a comb structure in the presence of an inhomogeneous convection flow is studied [Baskin and Iomin, Phys. Rev. Lett. 93, 120603 (2004)]. The large scale asymptotics is considered. It is shown that a contaminant spreads superdiffusively in the direction opposite to the convection flow. Conditions for the realization of this effect are discussed in detail.

Journal Article↗

Relationship between chronic inflammation and cardiovascular risk factors in children on maintenance hemodialysis.

Cardiovascular disease is one of the most important causes of morbidity and mortality in children with end-stage renal failure. Chronic inflammation and malnutrition have been suggested to be risk factors for cardiovascular disease. However, to date, biomarkers of inflammation have not been well studied in children. The aim of this study was to investigate the relation between chronic inflammation and cardiovascular risk factors in children on hemodialysis therapy. Twenty-seven patients on hemodialysis (14 girls, 13 boys) of mean age 15.3 +/- 2.4 years and 20 healthy children (13 girls, 7 boys) of mean age 14.3 +/- 2.7 years were included the study. C-reactive protein (CRP), albumin, prealbumin, transferrin, ferritin, and fibrinogen were measured as the markers of inflammation. The levels of CRP, ferritin, and erythrocyte sedimentation rate among hemodialysis patients were significantly higher than those of control subjects (P < .001 for all). Albumin and transferrin levels were found to be lower than those of control group (P = .02 and P < .001, respectively). CRP levels were negatively correlated with albumin, prealbumin, apoprotein A1, HDL, and hemoglobin levels, and positively correlated with erythropoietin/Htc ratios. This study suggests that hemodialyzed children are exposed to chronic inflammation. In addition, CRP may be an indicator of chronic inflammation related to cardiovascular risk factors, such as malnutrition, dyslipidemia, and anemia. In conclusion, we suggest that the risk of cardiovascular disease could be reduced by defining markers of chronic inflammation and malnutrition in hemodialyzed children and by taking necessary measures at an early stage.

Adolescent↗

Relationship between leptin and bone mineral density in renal transplant recipients.

INTRODUCTION: Leptin plays an important role in regulating appetite and energy expenditure and also functions in the neuroendocrine, hematopoietic, and immune systems, among others. Leptin may be involved in modulating bone mineralization. The relationship between leptin and bone mineral density (BMD) is not clear. This study examined the relationship between BMD and serum leptin levels in renal transplant recipients. MATERIALS AND METHODS: Forty-one patients (28 men and 13 women; age 16 to 55 years) were grouped according to percentile of serum leptin level hypoleptinemic (<5th percentile, n = 14), normoleptinemic (between the 5th and 95th percentiles, n = 19), or hyperleptinemic (>95th percentile, n = 8). The patients also were grouped according to lumbar z score) and total femur z scores (>-2 vs <-2 for both). RESULTS: The groups with different leptin statuses were compared with respect to age, sex distribution, and body mass index. Mean lumbar z score and mean lumbar BMD were higher in the hyperleptinemic group than in the normo- and hypoleptinemic groups (P < .05 for all). Considering the 42 patients overall, those with lumbar z scores >-2 had higher mean serum leptin/BMI than those with lumbar z scores <-2 (0.55 +/- 0.65 vs 0.18 +/- 0.23, respectively, P < .05). Serum leptin/BMI ratio was correlated with lumbar z score (r = .38, P < .05) and lumbar BMD (r = .32, P < .05). CONCLUSION: In conclusion, the data indicate that elevated leptin level is associated with increased bone mass at lumbar sites in renal transplant recipients. This suggest that increased leptin has a bone-sparing effect, especially in the lumbar region, in this patient group.

Adolescent↗

Superdiffusion on a comb structure.

We study specific properties of particles transport by exploring an exact solvable model, a so-called comb structure, where diffusive transport of particles leads to subdiffusion. A performance of the Lévy-like process enriches this transport phenomenon. It is shown that an inhomogeneous convection flow is a mechanism for the realization of the Lévy-like process. It leads to superdiffusion of particles on the comb structure. This superdiffusion is an enhanced one with an arbitrary large transport exponent, but all moments are finite. A frontier case of superdiffusion, where the transport exponent approaches infinity, is studied. The log-normal distribution with the exponentially fast superdiffusion is obtained for this case.

Journal Article↗

Nephrolithiasis associated with ceftriaxone therapy: a prospective study in 51 children.

BACKGROUND: Ceftriaxone, a third generation cephalosporin, is widely used for treating infection during childhood. The kidneys eliminate approximately 33-67% of this agent, and the remainder is eliminated via the biliary system. Ceftriaxone may bind with calcium ions and form insoluble precipitate leading to biliary pseudolithiasis. The aim of this study was to assess whether ceftriaxone associated nephrolithiasis develops by the same mechanism, and whether this condition is dose related. METHODS: The study involved 51 children with various infections. Of these, 24 were hospitalized with severe infection and received 100 mg/kg/day ceftriaxone divided into two equal intravenous doses. The other 27 patients received a single daily intramuscular injection of 50 mg/kg/day. Serum and urine parameters were evaluated before and after treatment, and abdominal ultrasonographic examinations were also carried out before and after treatment. RESULTS: Serum urea, creatinine, and calcium levels were normal in all patients before and after treatment. Post-treatment ultrasound identified nephrolithiasis in four (7.8%) of the 51 subjects. The stones were all of small size (2 mm). Comparison of the groups with and without nephrolithiasis revealed no significant differences with respect to age, sex distribution, duration of treatment, or dose/route of administration of ceftriaxone. The renal stones disappeared spontaneously in three of the four cases, but were still present in one patient 7 months after ceftriaxone treatment. CONCLUSIONS: Conclusions: The study showed that children taking a 7 day course of normal or high dose ceftriaxone may develop small sized asymptomatic renal stones. The overall incidence of nephrolithiasis in this study was 7.8%.

Adolescent↗

The significance of antineutrophil cytoplasmic antibody in microscopic polyangitis and classic polyarteritis nodosa.

AIMS: To describe the distribution and features of classic polyarteritis nodosa (PAN) and microscopic polyarteritis (MPA) and the importance of antineutrophil cytoplasmic antibody (ANCA) in childhood PAN. METHODS: Classic PAN was diagnosed in 15 patients based on the presence of aneurysms on angiography in 10 patients and of necrotising vasculitis in medium sized arteries in five. MPA was diagnosed in 10 patients, based on characteristic findings at renal biopsy in six and by the presence of small sized necrotising arteritis in four. Serum ANCA was detected initially by indirect immunofluorescence (IIF) followed by an immunoassay for myeloperoxidase (MPO) in each case. RESULTS: The median age of the patients with classic PAN and MPA was 12 (range 8-17) and 9.5 (range 5-14) respectively. None of the patients with classic PAN had renal failure. Six of the patients with MPA presented with renal failure; four progressed to chronic renal failure. Clinically evident pulmonary-renal syndrome was present in three of the 10 patients with MPA. IIF for ANCA in classic PAN was negative in nine, showed mild staining patterns in six, and in one MPO-ELISA was mildly increased. IIF for ANCA in MPA revealed very strong perinuclear ANCA staining in nine and atypical staining in one. In MPA, median MPO-ELISA level was 42.5 EU/ml (range 20-250). Treatment of childhood PAN was satisfactory with effective treatment; however relapses did occur. CONCLUSION: ANCA is useful in the diagnosis and follow up of MPA.

Adolescent↗

Comparative study of cefixime alone versus intramuscular ceftizoxime followed by cefixime in the treatment of urinary tract infections in children.

Urinary tract infections (UTI) can cause acute morbidity and may result in severe problems, including hypertension and reduced renal function. Diagnosis of UTI is extremely important since prompt treatment may prevent damage. In the present study we compared the efficacy of oral cefixime to initial intramuscular ceftizoxime followed by cefixime for the treatment of UTI in children. Fifty-four children were studied. They were randomized to receive either oral cefixime 8 mg/kg/day for 10 days or initial intramuscular ceftizoxime (Cefizox) 50 mg/kg twice a day for 2 days followed by oral cefixime for 8 days. Treatment groups were comparable regarding age, sex, clinical, and laboratory findings. Escherichia coli was isolated from 80% of patients. Repeat urine cultures were sterile within 24 hours in all children. Cure rates were comparable in both groups (92% vs 86% at the end of treatment). No serious adverse effects were observed. We concluded that oral cefixime is a safe and effective alternative treatment.

Adolescent↗

Carbamazepine poisoning: treatment with plasma exchange.

Lethal cases due to carbamazepine overdose have been reported. There are contradicting reports about the efficiency of hemodialysis, hemoperfusion and plasmapheresis for the treatment of carbamazepine poisoning. We present a case of carbamazepine intoxication successfully managed with plasma exchange. The patient was a 15-year-old girl. On admission there was no evidence of trauma, Glascow Coma Scale scored 6. Further questioning of the parents revealed the patient had taken at least 23 tablets of Tegretol (4.6 g) 6 h before the admission. The carbamazepine level was 190 micromol/l. Orogastric lavage was followed by activated charcoal. Within 20 h after admission there was no improvement in her neurological status. It was thus decided to perform plasmapheresis. At the end of the procedure she started to respond to verbal stimuli. Carbamazepine level immediately after the procedure was 101 micromol/l, and at the 36th, 60th and 84th hours were 72, 33 and 20 micromol/l, respectively. The patient was discharged on the fourth day. We have not observed any rebound in our patient. Thus we suggest that simple plasma exchange by plasma replacement is a cheaper and effective method for the treatment of intoxication with carbamazepine or similar drugs.

Adolescent↗

Vascular endothelial growth factor in Henoch-Schonlein purpura.

OBJECTIVE: To investigate the possible role of vascular endothelial growth factor (VEGF) in the pathogenesis of Henoch-Schonlein purpura (IHSP). METHODS: Plasma VEGF levels were determined in 22 children by ELISA. Ten age matched healthy children served as controls. VEGF expression was evaluated by immunohistochemistry within the cutaneous vasculitic lesion as well as the nonaffected skin and in the skin specimens during the resolution of the disease. RESULTS. Plasma VEGF levels in pg/ml (mean +/- SE) were significantly higher during the acute phase (407.8 +/- 64.92) when compared with the levels seen during the resolution phase (202.17 +/- 26.6; p < 0.002) and in healthy controls (135 +/- 22.8; p < 0.001). Analysis showed that there was a correlation with erythrocyte sedimentation rate. C-reactive protein, white blood cell and platelet count. In all skin specimens, the intensity of the staining of VEGF in the epidermis, dermis, and vascular endothelial bed were evaluated and scored from (+) to (++++). VEGF expression in the epidermis and the vascular bed was more intense in resolving lesions compared with acute vasculitic lesions (p < 0.05). CONCLUSION: Our results suggest that as a potent permeability, chemotactic, and migratory factor, VEGF may play a crucial role in the morphological and functional changes of the vascular bed and inflammatory reaction in HSP.

Acute-Phase Reaction↗

Renal vascular abnormalities in Bardet-Biedl syndrome.

Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disorder. Specific diagnostic criteria for BBS have now been defined. At least four of the five cardinal signs of mental retardation, obesity, hypogenitalism in men, distal limb anomalies, and progressive tapetoretinal degeneration of the retina are required for the diagnosis. Renal involvement has been described as a sixth cardinal feature. Chronic renal failure occurs in 30%-60% of patients. Hypertension has been noted in 50%-66% of cases. Renal abnormalities reflect a defect in maturation of the kidneys. We present a patient with BBS who had bilateral microaneurysms and occlusions in renal arterioles.

Aneurysm↗

Biological profile of L-745,870, a selective antagonist with high affinity for the dopamine D4 receptor.

L-745,870,(3-([4-(4-chlorophenyl)piperazin-1-yl]methyl)-1H- pyrollo[2,3-b] pyridine, was identified as a selective dopamine D4 receptor antagonist with excellent oral bioavailability and brain penetration. L-745,870 displaced specific binding of 0.2 nM [3H] spiperone to cloned human dopamine D4 receptors with a binding affinity (Ki) of 0. 43 nM which was 5- and 20-fold higher than that of the standard antipsychotics haloperidol and clozapine, respectively. L-745,870 exhibited high selectivity for the dopamine D4 receptor (>2000 fold) compared to other dopamine receptor subtypes and had moderate affinity for 5HT2, sigma and alpha adrenergic receptors(IC50 < 300 nM). In vitro, L-745,870 (0.1-1 microM) exhibited D4 receptor antagonist activity, reversing dopamine (1 microM) mediated 1) inhibition of adenylate cyclase in hD4HEK and hD4CHO cells; 2) stimulation of [35S] GTPgammaS binding and 3) stimulation of extracellular acidification rate, but did not exhibit any significant intrinsic activity in these assays. Although standard antipsychotics increase dopamine metabolism or plasma prolactin levels in rodents, L-745,870 (</=30 mg/kg p.o.) had no effect in these assays. The lack of a suitable in vivo assay for D4 receptor activation prompted the use of in vivo surrogate marker assays which confirmed that doses of 5-60 microg/kg L-745,870 would be sufficient to occupy 50% D4 receptors in the brain. These results show that dopamine D4 receptor antagonism in the brain does not result in the same neurochemical consequences (increased dopamine metabolism or hyperprolactinemia) observed with typical neuroleptics.

Animals↗

Effects of protein energy malnutrition on circulating thyroid hormones.

The effect of protein energy malnutrition (PEM) in the children on serum levels of total thyroxine (TT4), total triodothyronine (TT3) and thyrotropin (TSH) were evaluated. There were 107 children aged 2 to 60 months in the malnutrition group and 54 healthy age and sex matched controls. Serum TT4 and TT3 were all reduced in the malnutrition group. This decrease in TT3 was more significant (p < 0.01) in severe malnutrition than in mild PEM. Serum TSH levels in the malnutrition and control groups were similar. These results suggest that the children remained euthyroid and represent an adaptive response to protein energy malnutrition.

Case-Control Studies↗