Putative Biological Mechanisms of Efficiency of Substrate Reduction Therapies for Mucopolysaccharidoses

Mucopolysaccharidoses (MPS) are inherited metabolic diseases caused by mutations in genes coding for lysosomal enzymes involved in the degradation of glycosaminoglycans (GAGs). Dysfunction of any of these enzymes results in the accumulation of GAGs, which leads to severe clinical symptoms and significantly shortened life span. Several kinds of therapies have been proposed to treat MPS, including bone marrow or stem cell transplantation, enzyme replacement therapy, and gene therapy. Another option is substrate reduction therapy (SRT), in which synthesis of GAGs is inhibited. Recent studies employing in vitro and animal models suggested that this therapy may be efficient in decreasing levels of GAGs in MPS cells, including those bearing two null alleles of the affected gene. Results of behavioral tests in animals as well as some preliminary clinical observations with pediatric patients corroborated the suggestions about possible efficacy of SRT in MPS treatment, including brain functions. Efficient reduction of GAG levels in MPS cells homozygous for null mutations may be intriguing in the commonly accepted scheme of SRT mode of action. In this paper, we propose an explanation of this phenomenon, based on already known facts. Thus, we suggest that SRT may lead to reduction of GAG levels in MPS cells due to inhibition of efficiency of GAG synthesis combined with (a) any readthrough of the stop codon, (b) dilution of already accumulated GAGs due to cell growth followed by cell divisions, and (c) action of endoglycosidases degrading GAGs, e.g., heparanase, in combination with functional GAG-specific hydrolases.     

Physical development in children and adolescents with bronchial asthma

Bronchial asthma is the most common chronic disease in children of developmental age. Data from the auxological literature indicate that children with disturbances in growth may also suffer from atopic disorders. The aim of the present study was to evaluate somatic growth in children with bronchial asthma using anthropological methods. The study was carried out using anthropometric measurements and information on the severity and course of the disease on 261 children with bronchial asthma. Mean body height was lower than in healthy peers and about 5% of subjects were short. Mean BMI and skinfold thicknesses were significantly higher and lean body mass was lower in the study group. Seventeen percent of the children were overweight or obese, and 8% were underweight. Body build was more robust in the girls examined. Longitudinal studies will help determine to what degree the disease itself directly affects physical development, and to what degree treatment does.     

Anti-osteopenic effect of alpha-ketoglutarate sodium salt in ovariectomized rats

The purpose of the study was to determine the effect of alpha-ketoglutarate sodium salt (AKG) treatment on the mineralization of the tibia in female rats during the development of osteopenia (Experiment-1) and in the condition of established osteopenia (Experiment-2). Thirty-two female rats were ovariectomized (OVX) to induce osteopenia and osteoporosis and another 32 female rats were sham-operated (SHO) and then randomly divided between the two experiments. In Experiment-1, the treatment with AKG started after a 7-day period of convalescence, whereas in Experiment-2 the rats were subjected to a 60-day period of osteopenia fixation, after which the actual experimental protocol commenced. AKG was administered in the experimental solution for drinking at a concentration of 1.0?mol/l and a placebo (PLC) was used as a control solution. After 60?days of experimental treatment the rats in both experiements were sacrificed, the body weight recorded, and blood serum and isolated tibia were stored for further analysis. The bones were analyzed using tomography and densitometry, and for estimation of mechanical properties the 3-point bending test was used. Serum concentrations of osteocalcin and collagen type I crosslinked C-telopeptide were measured. The anabolic effects of AKG on bone during osteopenia development in Experiment-1 not only stopped the degradation of bone tissue, but also stimulated its mineralization. The usage of AKG in animals with established osteopenia (Experiment-2) was not able to prevent bone atrophy, but markedly reduced its intensity. The stimulation of tibia mineralization after AKG treatment has been also argued in healthy SHO animals. The results obtained prove the effectiveness of AKG usage in the prophylaxis and therapy of osteopenia and osteoporosis, induced by bilateral gonadectomy. Additionally, the results clearly prove that treatment with AKG improves the mineralization of bone tissue in healthy animals.     

Association Between Prediagnostic Serum 25-Hydroxyvitamin D Concentration and Glioma

There are no previous studies of the association between prediagnostic serum vitamin D concentration and glioma. Vitamin D has immunosuppressive properties; as does glioma. It was, therefore, our hypothesis that elevated vitamin D concentration would increase glioma risk. We conducted a nested case-control study using specimens from the Janus Serum Bank cohort in Norway. Blood donors who were subsequently diagnosed with glioma (n = 592), between 1974 and 2007, were matched to donors without glioma (n = 1112) on date and age at blood collection and sex. We measured 25-hydroxyvitamin D [25(OH)D], an indicator of vitamin D availability, using liquid chromatography coupled with mass spectrometry. Seasonally adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated for each control quintile of 25(OH)D using conditional logistic regression. Among men diagnosed with high grade glioma >56, we found a negative trend (P = .04). Men diagnosed ≤ 56 showed a borderline positive trend (P = .08). High levels (>66 nmol/L) of 25(OH)D in men >56 were inversely related to high grade glioma from ≥2 yr before diagnosis (OR = 0.59; 95% CI = 0.38, 0.91) to ≥15 yr before diagnosis (OR = 0.61; 95% CI = 0.38,0.96). Our findings are consistent long before glioma diagnosis and are therefore unlikely to reflect preclinical disease.     

Add-on treatment with nebulized hypertonic saline in a child with plastic bronchitis after the Glenn procedure,

Plastic bronchitis (PB), although a rare cause of airway obstruction, has mortality rates up to 50% in children after Fontan-type cardiac surgery. We present the case of an 18-month-old female patient with PB following pneumonia. At 6 months of age, the patient underwent the Glenn procedure due to functionally univentricular heart. Fiberoptic bronchoscopy revealed complete blockage of the left bronchus by mucoid casts. Pharmacotherapy consisted of glucocorticosteroids, azithromycin, and enalapril maleate. The child also received nebulized 3% NaCl solution, which proved to be beneficial. In children submitted to Fontan-type procedures, physicians must be alert for PB, which can be triggered by respiratory tract infection.     

Double teeth: evaluation of 10-years of clinical material

The aim of the study was to evaluate 10-years of clinical material referring to the rare dental abnormality of double teeth. The study material consisted of case records, operation-books and radiographic or photographic documentation on patients treated in the Department of Oral Surgery, Silesian Medical University, Katowice, from the 1st of June 2000 to the 31st of May 2010. The following features were considered important: age and sex, the reason why the patient reported for treatment, general state of health, the time of recognition and type of double teeth, location of double teeth, complaints and disturbances connected with double teeth, types of radiographs, the radiographic and macroscopic appearance of double teeth and treatment method. Diagnoses were as follows: eight conrescent teeth, two fused teeth, two geminated teeth and one invaginated tooth. The anomaly of a deciduous tooth was referred to in one case only. Double teeth were most often seen in the region of maxillary incisors and molars but rarely in the mandible. The region of incisors was affected chiefly in children and the region of molars in adults. Double incisors are usually recognized prior to treatment whereas double molars as late as during their extraction. In many cases, neither intraoral radiographs nor pantomographs help to confirm double teeth or provide sufficient information to plan the treatment. In such a situation, CT or CBCT should be used in addition to imaging diagnostics. Double teeth among incisors are usually accompanied by occlusal disorders. Therefore the therapeutic management is conducted by a team, including orthodontists.