Plasma amino acid profile in autism spectrum disorder (ASD)

OBJECTIVE

In our study, we aimed to reveal pathophysiologic mechanisms in ASD by comparing plasma amino acid levels between patients and healthy controls while considering vitamin B12 and D levels.

PATIENTS AND METHODS

The study included 21 patients aged 2-18 years-old who were followed with a diagnosis autism spectrum disorder (ASD) and 21 age and sex-matched healthy children from our outpatient clinic as control group.

RESULTS

The study included 42 children and adolescents aged 2-18 years-old (19 girls and 23 boys). There were no significant differences in terms of body weight and height between the groups. We found significant differences in levels of ammonium, phosphoethanolamine, histidine, homocysteine, carnosine, methionine, cystathionine, cystine, threonine, 3-methyl histidine and phenylalanine/tyrosine ratio between patient and control groups. Both vitamin B12 and D were significantly lower in the ASD group compared to controls. In the variance analysis with vitamin B12 and D as covariates, significant differences persisted for only phosphoethanolamine (p=0.04), cystathionine (p<0.001), cystine (p=0.006) and threonine (p=0.02).

CONCLUSIONS

Further studies are needed on the amino acids that show variations in children with ASD in order to reveal their role in the etiology and therapeutic use in ASD.

Role of circulating nesfatin-1 in the underweight children with poor appetite

OBJECTIVE

To investigate serum concentration of nesfatin-1 in underweight children who have poor appetite, and its association with anthropometric markers of malnutrition.

PATIENTS AND METHODS

We recruited 50 underweight children and adolescents (aged 2-18 years) who presented with loss of appetite. Thirty age- and sex-matched controls were also included in the study. Fasting serum nesfatin-1 concentrations were measured by using Enzyme-Linked Immunosorbent Assay (ELISA) technique.

RESULTS

Mean nesfatin-1 level was significantly higher in underweight children when compared to controls (p<0.001). There was no correlation between serum nesfatin-1 levels and anthropometrics markers.

CONCLUSIONS

Our results suggest that nesfatin-1 might have an important role in regulation of food intake and pathogenesis of loss of appetite in children.

Observation of zeroth-order band gaps in negative-refraction photonic crystal superlattices at near-infrared frequencies

We present the first observations of zero-n[over ] band gaps in photonic crystal superlattices consisting of alternating stacks of negative-index photonic crystals and positive-index dielectric materials in the near-infrared range. Guided by ab initio three-dimensional numerical simulations, the fabricated nanostructured superlattices demonstrate the presence of zeroth-order gaps in remarkable agreement with theoretical predictions across a range of different superlattice periods and unit cell variations. These volume-averaged zero-index superlattice structures present a new type of photonic band gap, with the potential for complete wave front control for arbitrary phase delay lines and open cavity resonances.

Complications of subduroperitoneal shunting

OBJECTS

Subduroperitoneal (SP) shunts have been widely used in the management of pediatric subdural fluid collections.

METHODS

We retrospectively reviewed the complications of SP shunting in 73 boys and 24 girls, who ranged in age from 1 to 180 months (median 7 months). Subdural fluid collection was bilateral in 75 and unilateral in 22 patients. The most common complication was shunt obstruction (13 patients). Shunt migration was seen in 8 patients. Migration occurred only with unishunts without a reservoir and with peritoneal catheters. However, the shunts with a reservoir or flushing valve led to skin necrosis in 4 patients (P=0.003). Unilateral drainage though bilateral collections were present, infection, bowel perforation, and ileus occurred in 5, 4, 1 and 1 patients respectively.

CONCLUSIONS

These SP shunt complications, some of which are avoidable, should be kept in mind.

Cerebral hydatid cysts in children

A parasitic tapeworm, called Taneia Echinococcus, causes hydatid disease. Hydatid disease is endemic in sheep and cattle-raising areas of the world. Hydatid disease of the central nervous system constitutes 2%-3% of all reported cases of hydatid cysts. In our institution, 23 children underwent surgery for intracranial hydatid cysts between 1979 and 1995. There were 14 boys and 9 girls, aged between 3 to 16 years (mean 8.8 years). Signs and symptoms were related to the site and size of the cyst. Headache and vomiting due to increased intracranial pressure were the most common presenting symptoms. A round cystic lesion without perifocal edema and rim enhancement is the characteristic appearance on a computed tomography (CT) scan. A magnetic resonance image visualizes cyst location better than CT. Associated systemic hydatidosis in four of our patients involved kidney, liver, lung, and liver and lung, respectively. Intact cyst removal was achieved in 14 patients. In three patients with infected or inflamed hydatid disease, the ruptured cyst capsule was totally resected. Aspiration and extirpation were performed in only one patient. Eleven patients were treated with chemotherapeutic agents such as albendazole or mebendazole due to cyst rupture during surgery or associated systemic hydatid disease. Hydatid disease can also be seen in Western countries because of travel and migration. Cerebral hydatid cyst should be kept in mind for the differential diagnosis of cystic lesions.

Split spinal cord malformations in children

OBJECT

The authors reviewed and analyzed information on 74 patients with split spinal cord malformations (SSCMs) treated between January 1, 1980 and December 31, 1996 at their institution with the aim of defining and classifying the malformations according to the method of Pang, et al.

METHODS

Computerized tomography myelography was superior to other radiological tools in defining the type of SSCM. There were 46 girls (62%) and 28 boys (38%) ranging in age from less than 1 day to 12 years (mean 33.08 months). The mean age (43.2 months) of the patients who exhibited neurological deficits and orthopedic deformities was significantly older than those (8.2 months) without deficits (p = 0.003). Fifty-two patients had a single Type I and 18 patients a single Type II SSCM; four patients had composite SSCMs. Sixty-two patients had at least one associated spinal lesion that could lead to spinal cord tethering. After surgery, the majority of the patients remained stable and clinical improvement was observed in 18 patients.

CONCLUSIONS

The classification of SSCMs proposed by Pang, et al., will eliminate the current chaos in terminology. In all SSCMs, either a rigid or a fibrous septum was found to transfix the spinal cord. There was at least one unrelated lesion that caused tethering of the spinal cord in 85% of the patients. The risk of neurological deficits resulting from SSCMs increases with the age of the patient; therefore, all patients should be surgically treated when diagnosed, especially before the development of orthopedic and neurological manifestations.

Continuous external subdural drainage in the management of infantile subdural collections: a prospective study

Continuous external subdural drainage (CESD) was suggested as a treatment step to be inserted prior to SP shunting, primarily because it makes it possible to avoid shunt placement in a significant number of patients. Thirty-three patients with symptomatic chronic subdural collection confirmed by computed tomography were included in this study. Unilateral CESD was performed in all cases, using a lumbar drainage set. The drains were left in place for no more than 10 days. A subduroperitoneal (SP) shunt was inserted in those patients in whom re-accumulation of the subdural collection had occurred. Of 33 patients, 17 were definitively treated by CESD and 16 subsequently needed an SP shunt. The cost of treatment with CESD was just less than half the cost of treatment with SP shunting. CESD can be used as a step before SP shunting in the management of chronic infantile subdural collections, since it is effective without further treatment in half the patients and safer than subdural tapping.

Immunoglobulin prophylaxis in shunt infections: a prospective randomized study

Cerebrospinal fluid shunt infection is serious and one of the most frequent complications of shunt implantation. Age has been one of the most significant host factors for the development of shunt infections. A relative deficiency of the immune response against bacteria in infants could partly explain the higher infection rate in the very young patients. This prospective-randomized study was conducted in two groups: group A (immunoglobulin group) and group B (control group). There were 30 patients in each group. The patients in group A received intravenous immunoglobulin (Sandoglobulin) at a dose of 1 g/kg in the night before surgery. Each patient was followed up to 6 months. No infection was seen in group A. In group B, infection rate per procedure were 5.1% (P = 0.494) and 6.6% (P = 0.492), respectively. Intravenous immunoglobulin prophylaxis in infants seems to reduce the shunt infections.