Low density lipoprotein receptor‐related protein 5 (LRP5) mutations and osteoporosis,impaired glucose metabolism and hypercholesterolaemia

Objective Mutations in the low‐density lipoprotein receptor‐related protein 5 gene (LRP5) underlie osteoporosis–pseudoglioma syndrome. Animal models implicate a role for LRP5 in lipid and glucose homeostasis. The objective was to evaluate metabolic consequences of LRP5 mutations in humans. Design and patients Thirteen Finnish individuals with homozygous or heterozygous LRP5 mutations were assessed for bone health, glucose and lipid metabolism, and for serum serotonin concentration. Results were compared with findings in family members without mutations. Measurements Bone mineral density (BMD), vertebral morphology, oral and intravenous glucose tolerance tests, lipid profile and serum serotonin concentrations. Results Two individuals were homozygous for R570W, one compound heterozygous for R570W and R1036Q, and 10 were heterozygous (six for R570W, three for R1036Q and one for R925C). Subjects with two LRP5 mutations had multiple spinal fractures and low BMD. Subjects with one mutation had significantly lower median lumbar spine (P = 0·004) and femoral neck (P = 0·005) BMD Z‐scores, and more often vertebral fractures than the 18 individuals without mutations. Of the 12 subjects with LRP5 mutation six had diabetes and one had impaired glucose tolerance. Intravenous glucose tolerance tests suggested impaired beta‐cell function; no insulin resistance was observed. Prevalence of hypercholesterolaemia was similar in mutation positive and negative subjects. Serum serotonin concentrations showed a trend towards higher concentrations in subjects with LRP5 mutation. Conclusions We found high prevalence of osteoporosis and abnormal glucose metabolism in subjects with LRP5 mutation(s). Further studies are needed to establish the role of LRP5 in glucose and lipid metabolism.     

Expression of cyclooxygenase-2 in dysplasia of the stomach and in intestinal-type gastric adenocarcinoma.

PURPOSE: Cyclooxygenase (Cox) is the key enzyme in conversion of arachidonic acid to prostanoids. Two Cox genes have been cloned, and expression of Cox-2 mRNA and protein has been shown to be elevated in several human malignancies and in animal models of carcinogenesis. The purpose of this study was to investigate Cox-2 protein expression in human gastric dysplasias and adenocarcinomas. EXPERIMENTAL DESIGN: Performance of several Cox-2 antibodies was evaluated, after which Cox-2 protein expression was studied in 67 gastric cancer specimens and in eight definitive dysplasias by using immunohistochemistry. RESULTS: Cox-2 positivity was detected in 58% (25/43) of the intestinal-type (well-differentiated) tumors and 6% (1/18) of diffuse-type (poorly differentiated) tumors. Consistent with these data, we detected higher expression of Cox-2 mRNA, protein, and enzymatic activity in well-differentiated gastric cancer cell lines (MKN-28 and MKN-74) when compared with poorly differentiated cell lines (HSC-39 and KATO III). Cox-2 immunoreactivity was localized to the carcinoma cells, but the stroma of the tumors was negative. However, strong Cox-2 positivity was consistently detected in stromal cells at sites of erosions and ulcerations. Furthermore, four of nine (44%) definitive dysplasias of the stomach that showed no evidence of invasion were positive for Cox-2. CONCLUSIONS: Cox-2 is expressed by the neoplastic cells in the intestinal-type gastric adenocarcinoma and by precarcinogenic (dysplastic) lesions leading to this disease.     

Coeliac disease in children and adolescents with type 1 diabetes: a study of growth,glycaemic control,and experiences of families

The aim of this study was to evaluate whether coeliac disease affects growth, glycaemic control, and general well-being of children and adolescents with type 1 diabetes. Eighteen subjects were found to have coeliac disease by a screening program. Gastrointestinal symptoms, changes in growth and the levels of glycated haemoglobin (GHbA1) were analysed, as well as subjective well-being before and after diagnosis of coeliac disease. Overt gastrointestinal symptoms and deterioration of growth prior to disclosure of coeliac disease were seen only in one patient who had both of these conditions. Retrospectively, most subjects reported mild gastrointestinal complaints, which resolved on a gluten-free diet. Introduction of a gluten-free diet did not have any positive effect on glycaemic control, but was associated with an increase in weight-for-height (from 4.3 ±18.1 to 8.2 ±15.4% deviation from population median, p = 0.02). This increase in weight-for-height was inversely correlated with changes in GHbA1 ( r =-0.574, p = 0.02).

Conclusion : Coeliac disease is rarely associated with signs of malabsorption in children and adolescents with type 1 diabetes. Introduction of a gluten-free diet may be associated with excess weight gain. We recommend intensified follow-up for these subjects.     

Integrin-mediated localization of Bordetella pertussis within macrophages: role in pulmonary colonization

The adherence of Bordetella pertussis to human respiratory cilia is critical to the pathogenesis of whooping cough but the significance of bacterial attachment to macrophages has not been determined. Adherence to cilia and macrophages is mediated by two large, nonfimbrial bacterial proteins, filamentous hemagglutinin (FHA), and pertussis toxin (PT). PT and FHA both recognize carbohydrates on cilia and macrophages; FHA also contains an Arg-Gly-Asp (RGD) sequence which promotes bacterial association with the macrophage integrin complement receptor 3 (CR3). We determined that virulent B. pertussis enter and survive in mammalian macrophages in vitro and that CR3 is important for this uptake process. We then determined the relative contribution of CR3 versus carbohydrate-dependent interactions to in vivo pulmonary colonization using a rabbit model. B. pertussis colonized the lung as two approximately equal populations, one extracellular population attached to ciliary and macrophage surface glycoconjugates and another population within pulmonary macrophages. Loss of the CR3 interaction, either by mutation of FHA or treatment with antibody to CR3, disrupted accumulation of viable intracellular bacteria but did not prevent lung pathology. In contrast, elimination of carbohydrate-bound bacteria, either by a competitive receptor analogue or an anti-receptor antibody, was sufficient to prevent pulmonary edema. We propose that CR3-dependent localization of B. pertussis within macrophages promotes persistence of bacteria in the lung without pulmonary injury. On the other hand, the presence of extracellular bacteria adherent to cilia and macrophages in carbohydrate-dependent interactions is associated with pulmonary pathology.     

Long-term prognosis for children with shunted hydrocephalus

We reviewed the previous medical history and the social status of all patients of Oulu University Central Hospital who had had in the age range 16–26 years shunted hydrocephalus (HC) during childhood. Of 42 patients selected 7 had died and another 5 had been institutionalized for severe mental handicap. Shunts had been changed a total of 103 times in 29 patients still living. The most common reason for a reoperation was blockage. Half of the patients re-examined showed neurological abnormalities or epilepsy. Both the verbal and the nonverbal IQ of the patients remained weak to average. Even though the patients' medical prognosis was fair, their social maturation did not keep up with their physical abilities. One-third were receiving or had received vocational training, but only a few were working. Up to one-quarter of the patients with shunted HC were at home without any meaningful work activities.     

Information value of magnetic resonance imaging in shunted hydrocephalus.

OBJECTIVE--To study the role of magnetic resonance imaging (MRI) in evaluating children with shunted hydrocephalus. METHODS--Sixty one asymptomatic children with shunted hydrocephalus or cystic cerebrospinal fluid collections were studied by cranial MRI. The information obtained from the images was classified into three categories: provided (1) a new diagnosis, (2) additional information, or (3) no essential new information. The findings were compared with those of the last follow up computed tomograms. RESULTS--MRI provided a new diagnosis in seven cases (11.5%), and additional information was obtained in 34 (55.7%) cases. In 20 cases (32.8%) no essential new information was obtained. MRI visualised white matter lesions and corpus callosum pathology more often than computed tomograms. CONCLUSIONS--MRI provided new important information in cases of children with shunted hydrocephalus to such an extent that it can be recommended as the primary imaging method for every child with this disorder.     

A syndrome with juvenile cataract, cerebellar atrophy, mental retardation and myopathy

Four patients of two families with clinical characteristics resembling those in Marinesco-Sj?gren syndrome are presented. All patients had infantile hypotonia as the presenting sign. In preschool age ataxia, cataract and mental retardation manifested. CT scan revealed cerebellar atrophy. Muscle biopsy showed myopathic changes with vacuolar degeneration and marked adipose tissue proliferation. Electron microscopy showed myelin bodies and autophagic vacuoles. The conclusion is that the peculiar myopathic and degenerative findings in the muscle biopsy are a consistent morphological feature in the clinical entity of the patients and the syndrome is distinctive from Marinesco-Sj?gren syndrome.