Ovariectomy in the rat induces a rapid increase in the urinary excretion of hydroxylysine glycosides and non-reducible crosslink residues

The ovariectomized rat is the most commonly used animal model of human postmenopausal osteoporosis, exhibiting a high rate of bone turnover with resorption exceeding formation. At present, bone turnover is quantified directly by dynamic histomorphometry. The aim of the present study was to determine whether the measurement of the urinary output of some specific bone collagen catabolites — pyridinolines and hydroxylysine glycosides — could be used to indirectly monitor the initial phase of bone turnover increase in ovariectomized 90-day-old rats. Ninety-day-old female rats were randomly divided into three groups (n=6): ovariectomized, sham-operated and non-treated controls. Urine samples (24 h) were collected 6 days before surgery and twice weekly for the 4 weeks following ovariectomy. Urinary excretion of pyridinoline (PYD), deoxypyridinoline (DPD), glucosyl-galactosyl-hydroxylysine (GGHYL) and galactosyl-hydroxylysine (GHYL) were measured. As expected, ovariectomy was associated with a significant decrease in bone mineral density in both the proximal tibial and distal femoral metaphysis. Compared with both sham-operated and control animals, ovariectomized rats showed significant increases in PYD, GGHYL and GHYL urinary output 8 days after surgery and in DPD output after 15 days. These changes were maintained throughout the study. The results confirm that measurement of the urinary excretion of pyridinolines and hydroxylysine glycosides represents a powerful tool for detecting the onset of bone turnover in ovariectomized 90-day-old rats.     

Opioid binding in DYT1 primary torsion dystonia: an 11C-diprenorphine PET study.

The opioid transmitters enkephalin and dynorphin are known to regulate pallidal output and consequently cortical excitability. Indeed, abnormal basal ganglia opioid transmission has been reported in several involuntary movement disorders, including levodopa-induced dyskinesias in Parkinson's disease (PD), tardive dyskinesias/dystonia, Huntington's disease, and Tourette's syndrome. Moreover, a previous 11C-diprenorphine PET study investigating levodopa-induced dyskinesias found reduced opioid receptor availability in PD with but not without dyskinesias. We wished to investigate if a similar alteration in basal ganglia opioid binding was present in DYT1 primary torsion dystonia (PTD). Regional cerebral 11C-diprenorphine binding was investigated in 7 manifesting carriers of the DYT1 gene and 15 age-matched normal controls using a region-of-interest (ROI) approach and statistical parametric mapping (SPM). No difference in regional mean 11C-diprenorphine binding was found between DYT1-PTD and controls, and no correlation between the severity of dystonia and opioid binding was seen. We conclude that aberrant opioid transmission is unlikely to be present in DYT1-PTD and altered opioid transmission is not a common mechanism underlying all disorders of involuntary movement.     

Chronic isolated macrothrombocytopenia with autosomal dominant transmission: a morphological and qualitative platelet disorder

Abstract: We studied 47 subjects belonging to 13 unrelated families with a history of mild haemorrhagic diathesis and chronic thrombocytopenia. 36 patients presented some degree of thrombocytopenia: 7/36 (19%) had slight thrombocytopenia (100–150×10⁹/L); 26/36 (72%) had mild thrombocytopenia (50–100×10⁹/L) and 3/36 (8%) had severe thrombocytopenia (<50×10⁹/L). No correlation was observed between platelet count and the degree of haemorrhagic diathesis, which was mild in the majority of patients. Transmission was autosomal dominant. Platelet anisocytosis, increased percentage of large platelets and absence of leukocyte inclusions were observed in 26/30 (87%) of the examined blood smears. The ultrastructural appearance of platelets was normal. Megakaryocytes appeared normal in number in 10/10 patients, but showed asynchronous nuclear-cytoplasm maturation and mainly nonlobulated nuclei. Platelet aggregation was studied in 26 patients and either increased or decreased curves were variably observed in response to different aggregating agents. Platelet-associated IgG (PAIgG) was increased in 18/31 (58%) patients, while serum autoantibodies against platelet glycoproteins Ib/IX or IIb/IIIa were demonstrable in only 1 case. An increased expression of platelet surface glycoproteins Ib and IIb/IIIa, as studied by murine monoclonal antibodies binding in 17 cases, was observed. Platelet survival performed by 111In-oxine-labelled autologous platelets was normal in the 3 studied patients. Congenital macrothrombocytopenia confirms to be a distinct clinical disorder for which the name of “chronic isolated hereditary macrothrombocytopenia” is proposed.     

Hemorrhagic vascular complications of endoscopic transsphenoidal surgery.

Two hundred and fifty consecutive patients operated on by an endoscopic endonasal transsphenoidal approach were retrospectively analyzed in order to evaluate hemorrhagic vascular complications occurring during or after the surgical procedure and their appropriate management. Vascular complications of endoscopic transsphenoidal surgery are identical to those of a microsurgical transsphenoidal approach. Damage to the sphenopalatine artery and to the internal carotid artery (ICA), which are the most frequent vascular troubles, may require technical tricks because of some aspects connected to the approach itself and of the physical properties of the endoscope. Furthermore, the progress in interventional neuroradiology in the last decades offers new solutions in respect to the past, where the use of the surgical microscope was already a tremendous progress. The anatomic substrate of each complication is discussed, along with the peculiar surgical details related to it.     

Histological score for cells with irregular nuclear contours for the diagnosis of reflux esophagitis in children

Histological criteria for the diagnosis of reflux esophagitis include basal zone hyperplasia, stromal papillae elongation, and inflammatory infiltrate. However, endoscopic esophageal biopsy specimens may include little or no lamina propria. Intraepithelial T lymphocytes, seen in hematoxylin and eosin-stained sections as cells with irregular nuclear contours (CINC), may have a higher density in children with esophagitis. We evaluated the diagnostic accuracy of a numerical score built up by grading the "classical" parameters and its correlation with CINC density in grasp biopsy specimens obtained from children undergoing esophagogastroduodenoscopy with and without esophagitis. We analyzed esophageal biopsy specimens from 349 children (median age, 5 years) subdivided in 4 groups according to the previous routine histology report: group 1, 144 children with esophagitis; group 2, 65 controls; group 3, 51 children with dubious esophagitis; and group 4, 75 children with esophagitis on endoscopy but a normal histology report. A numerical value was assigned to each parameter; the sum of these values represented the histological score. We also evaluated intraepithelial CINC density (ie, number of CINC per high-power field). We separately analyzed histological sections with and without lamina propria. For both total score and for CINC density, we calculated a cutoff using a receiver operating characteristic curve. Cutoffs of 6 for score and of 4 for CINC density provided the best sensitivity and specificity. Sensitivity of the histological score was better in biopsy specimens containing lamina propria (94%) than in those without lamina propria (4%). Sensitivity of CINC density was satisfactory in both specimens with (78%) and without (75%) lamina propria. Specificity was satisfactory for both parameters. In conclusion, when lamina propria was present in sections of endoscopic esophageal biopsy specimens, histological score provided a better diagnostic accuracy for the diagnosis of esophagitis. However, when no lamina propria was present, as was the case in 67% of our children, CINC density had better sensitivity. In addition, this latter parameter showed esophageal mucosa damage in 34% of previously dubious cases or cases with esophagitis at endoscopy but a previous routine histology report of normal mucosa.     

Two maturation-associated mouse erythrocyte receptors of human B cells. II. Isolation and partial characterization of a B-cell lectin with specificity of R1.

Trypsin treatment of chronic lymphocytic leukaemia (CLL) cells which have the capacity to rosette with mouse erythrocytes (M), the BM+ subtype, inhibits their capacity to rosette and releases a substance into the supernatant which agglutinates mouse and rat erythrocytes but not erythrocytes of five other species tested. This substance has been named immature B-cell lectin (IBL). The specificity of IBL was further demonstrated by fluorescence labelling, absorption and latex rosetting. IBL does not bind to pronase-treated M (pro M), indicating that it has the specificity of R1 as distinct from R2 which binds to a pronase-resistant ligand on M. Other evidence that IBL is associated with B-cell membrane receptors for mouse erythrocytes is as follows: (1) The amount of IBL released into the supernatant correlated with the trypsin sensitivity of M rosetting with different clones of BM+ CLL cells. (2) Only small amounts of IBL were released from non-rosetting cells (T cells and mature B cells). (3) Binding properties of IBL were inhibited by extract of M but not extract from ox erythrocytes. (4) High-titre solutions of IBL conferred the capacity to form M rosettes on certain types of non-rosetting B cells. IBL has a dual binding specificity. Its binding to M is inhibited by fetuin and mannan, while its binding to B cells is not inhibited by these substances. The relationship of IBL to other membrane lectins including fibronectin is discussed. Preliminary characterization indicates a high-molecular-weight (at least 300,000 daltons) glycoprotein which has a pronounced tendency to aggregate in solution. The relationship of IBL to stages of human B-cell maturation is discussed.     

Detection of expansion regions in Portuguese bipolar families

We have studied 24 families with multiple affected members with bipolar disorder to test the hypothesis that in those families clinically showing genetic anticipation [Macedo et al., 1999] we would find large repeat expansions. The families meeting inclusion criteria had a minimum of two affected members over two generations and showed marked anticipation both in terms of age of onset and disease severity. We used the repeat expansion detection (RED) method to test patients (n = 24) and controls from these families and unrelated controls (n = 53). We also genotyped patients and family members from two families with large expansions at the known expansion loci on chromosomes 13, 17, and 18. The RED method revealed a higher number of large expansions in patients compared with controls (t-test; P < 0.0055: Mann-Whitney U; P = 0.02). The patients with the largest expansions were typed at the specific loci on chromosomes 13, 17, and 18 and the chromosome 18 expansion locus segregated with disease in one family, and a second family showed segregation with the expansion located at the SCA8 locus on chromosome 13. Genetic anticipation had been analyzed in this cohort of families, with correction for potential ascertainment bias, possible proband effects, cohort effects, regression to the mean, gender effects, and maternal vs. paternal transmission. None of these potential confounds appeared to account for the observed anticipation. We also identified that the presence of large expansions in affected family members derives primarily from two families from the genetically isolated Azores population. One family shows segregation with the chromosome 18 locus, whereas the other family segregates with expansions at the SCA8 locus. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:854-857, 2000.