Effects on molecular conformation and anticoagulant activities of 1,6-anhydrosugars at the reducing terminal of antithrombin-binding octasaccharides isolated from low-molecular-weight heparin enoxaparin

Terminal 1,6-anhydro-aminosugars (1,6-anAS) are typical structural moieties of enoxaparin, a low-molecular-weight heparin (LMWH) widely used for prevention and treatment of thrombotic disorders. In the enoxaparin manufacturing process, these modified amino sugars are formed during the β-eliminative cleavage of heparin. To investigate the effect of terminal anAS on antithrombin (AT) binding and on inhibition of factor Xa (FXa), two octasaccharides containing modified AT-binding pentasaccharide sequences were isolated from enoxaparin. The molecular conformation of the octasaccharides terminating with N-sulfo-1,6-anhydro-D-mannosamine and N-sulfo-1,6-anhydro-D-glucosamine, respectively, has been determined both in the absence and presence of AT by NMR experiments and docking simulations. Reduced overall contacts of the terminal anAS residues with the binding region of AT induce a decrease in affinity for AT as well as lower anti-FXa activity. The anti-FXa measured either in buffer or plasma milieu does not show any significant difference, suggesting that the inhibition of anti-FXa remains specific and biologically relevant.     

Microvascular adaptation to growth in rat humeral head

The aim of this work is to investigate the growth of the vasculature in the rat humeral head cartilage after the initial development of the secondary ossification centre until the adult organization. Rats aging from 5 weeks to 12 months were used. Histological observations on humeral heads were implemented with morphometrical analysis. Subsequently, vascular corrosion cast, that permits a three-dimensional observation of the vasculature, were prepared and observed by scanning electron microscopy. In young animals the epiphysis contains thin bone trabeculae and most of the epiphysis is occupied by bone marrow spaces. With age, the bone trabeculae progressively enlarge up to double their thickness. The percentage of bone tissue increases from 33.6 to 58.6% of the entire epiphysis, while the bone marrow spaces tend to increase very little in their mean dimension. Vascular corrosion casts show that the epiphyseal microcirculation is well distinguished from that of the diaphysis, and arises from the vessels present in the capsule and the periosteal networks. In young animals the only capillaries are bone marrow sinusoids and few subchondral capillaries. In adult animals small vessels run between the clusters of sinusoids forming the trabecular circulation. Capillary sprouts from sinusoids are always observed both in the young and adult animals. Thus, in adult rats different proper microcirculatory districts can be distinguished in the epiphysis: (a) the sinusoidal network, that supplies the hematopoiesis of the bone marrow and the adjacent osteogenic tissue; (b) the bone tissue microcirculation, limited to small vessels that supply the metabolism and the remodelling of the bone tissue. The reported microvascular organization and its adaptation to the epiphyseal growth represent the morphological basis for understanding the reciprocal interaction among the different tissues in developing and adult rat epiphysis.     

Clinical features of reflux esophagitis in older people: a study of 840 consecutive patients

OBJECTIVES: To compare symptoms and other clinical characteristics of reflux esophagitis in patients of different ages. DESIGN: Observational cross-sectional study of consecutive patients. SETTING: Geriatric Unit, Casa Sollievo della Sofferenza Hospital, Istituto di Ricovero e Cura a Carattere Scientifico. PARTICIPANTS: Eight hundred forty patients with endoscopically diagnosed erosive esophagitis divided into four groups according to age (young (<50, mean 36.7, n=114), adult (50-69, mean 59.1, n=126), elderly (70-84, mean 77.3, n=425), and very elderly (>or=85, mean 88.4, n=175)). MEASUREMENTS: Gastrointestinal symptoms were evaluated using the Gastrointestinal Symptom Rating Scale questionnaire. Other symptoms were recorded when present as an indication for endoscopy. Severity of esophagitis, presence of Helicobacter pylori infection, presence and size of hiatus hernia, Barrett's esophagus, antrum or corpus gastric atrophy, and nonsteroidal antiinflammatory drug (NSAID) use were also evaluated. RESULTS: Elderly and very elderly patients had a significantly lower prevalence of typical gastroesophageal reflux disease symptoms (heartburn or acid regurgitation (P<.001) and epigastric pain (P<.001)) than young and adult patients. Conversely, the prevalence of other symptoms (anorexia (P<.001), weight loss (P<.007), anemia (P<.001), vomiting (P<.001), and dysphagia (P<.001)) significantly increased with age. The prevalence of severe esophagitis (P<.001), hiatus hernia (P<.005), the size of hiatus hernia (P<.001), antrum and corpus gastric atrophy (P<.05) and NSAID use (P<.005) also significantly increased with age. Multivariate analysis demonstrated that older age (65-84, odds ratio (OR)=2.66, 95% confidence interval (CI)=1.38-5.12; >or=85, OR=4.57, 95% CI=2.15-9.71), hiatus hernia larger than 3 cm in diameter (OR=2.38, 95% CI=1.41-4.01), and male sex (OR=2.83, 95% CI=1.72-4.64) are independent risk factors for severe esophagitis, whereas H. pylori infection, gastric atrophy, NSAID use, and the presence of hiatus hernia were not. CONCLUSION: Elderly patients with reflux esophagitis had less-typical and more-nonspecific symptoms than young or adult patients. Old age, male sex, and hiatus hernia size greater than 3 cm are significantly associated with severe esophagitis. Clinicians caring for older patients should be aware of the nonspecific presentation and potential severity of reflux esophagitis in this population.     

Is it possible to predict the clinical course of gallstone disease? Usefulness of gallbladder motility evaluation in a clinical setting

OBJECTIVE: A knowledge of the predictive factors of the development and persistence of symptoms in gallstone patients (GS) plays a key role in clinical decision making. The aim of this study was to evaluate the presence of predictive factors for biliary pain development in GS, stressing the role of gallbladder motility. METHODS: A total of 153 (104 women, 49 men) consecutive GS were enrolled. Gallbladder motility (%Emptying [%E], residual volume [RV]) was evaluated by ultrasonography and biliary symptoms were evaluated using a specific questionnaire in all GS at baseline and after 4 yr of follow-up. RESULTS: At enrolment, 61 GS reported recent (GSr) and 31 GS remote (GSo) (>2 yr before) episodes of biliary pain, and 61 were asymptomatic (GSa). At baseline, GSr showed a greater %E and a smaller RV than both GSo and GSa (p < 0.001). After follow-up, biliary pain developed more frequently in GSr (33.3%) than in GSo (16%) and GSa (15%) (p= 0.04). The search for predictive factors of biliary pain development (by univariate and multivariate analyses) revealed a high %E, a small RV, and a history of biliary pain as risk factors. CONCLUSIONS: Efficient gallbladder motility is present in symptomatic GS and it represents a risk factor for biliary pain development while sluggish motility seems to play a protective role. Thus, gallbladder motility evaluation is a useful diagnostic tool in clinical decision making for GS; in symptomatic GS, a progressive reduction of gallbladder motility could suggest a "wait and see" management policy instead of an immediate surgical approach.     

Growth hormone (GH) pharmacogenetics: influence of GH receptor exon 3 retention or deletion on first-year growth response and final height in patients with severe GH deficiency

CONTEXT: A polymorphism in GHR gene, the presence or absence of exon 3, has been shown to influence the 1- and 2-yr growth responses to human recombinant GH (hGH) therapy in children without GH deficiency (GHD). OBJECTIVE: The objective of this study was to assess the influence of GHR-exon-3 genotype on the short and long-term response to hGH therapy in children with GHD. SETTING: The study was conducted in the university hospital. DESIGN AND PATIENTS: Genotype and retrospective analysis was performed on data of 75 children with GHD. Intervention: Intervention consisted of hGH treatment at a mean dose of 33 mug/kg.d and GHR-exon-3 genotype by multiplex PCR. MAIN OUTCOME MEASURES: The main outcome measures were GHR genotype: full-length (fl) and exon 3-deleted (d3) alleles, growth velocity in 58 children who remained prepubertal during the first year, and adult height in 44 patients with GHD after 7.5 +/- 3.0 yr of treatment. RESULTS: Clinical and laboratory data at the start of treatment and hGH doses were indistinguishable among patients with different GHR-exon-3 genotypes (fl/fl vs. fl/d3 or d3/d3). Patients carrying at least one GHRd3 allele had a significantly better growth velocity in the first year of hGH replacement (12.3 +/- 2.6 vs. 10.6 +/- 2.3 cm/yr; P < 0.05) and achieved a taller adult height (final height sd score, -0.8 +/- 1.1 vs. -1.7 +/- 1.2; P < 0.05) when compared with patients homozygous for GHRfl alleles. CONCLUSIONS: Patients with GHD who are homozygous for GHR exon 3 fl were less responsive to short- and long-term hGH therapy. Approximately half of the population is homozygous for GHRfl, and future studies adjusting hGH therapy to genotype may improve outcome.     

Interleukin-10 promoter polymorphisms in giant cell arteritis

OBJECTIVE: To investigate potential associations between interleukin-10 (IL-10) promoter polymorphisms and susceptibility to, and clinical features of, giant cell arteritis (GCA). METHODS: A total of 140 patients with biopsy-proven GCA who were residents of Reggio Emilia, Italy, and 200 population-based controls from the same geographic area were genotyped for promoter polymorphisms of the IL-10 gene, by molecular methods. The patients were subgrouped according to the presence or absence of polymyalgia rheumatica (PMR) and ischemic complications (any or all of the following: vision loss, jaw claudication, cerebrovascular accidents, or aortic arch syndrome). RESULTS: The distribution of the C/A 592 genotype differed significantly between the GCA patients and the controls (P(corr) = 0.003). Carriers of the A592 allele (A/A or C/A) were significantly more frequent among the GCA patients than among the controls (P(corr) = 0.004, odds ratio [OR] 2.0 [95% confidence interval (95% CI) 1.3-3.1]). Homozygosity for the A592 allele was significantly more frequent among the GCA patients than among the controls (P(corr) = 0.002, OR 3.4 [95% CI 1.6-7.2]). The distribution of the A/G 1082 genotype was similar in GCA patients and controls. In the haplotype analysis, the frequency of the ATA haplotype was significantly higher in GCA patients than in the controls (P = 0.0001), whereas the frequencies of the ACC and GTA haplotypes were significantly lower (P = 0.0001 for both comparisons). No significant associations were found for comparisons of GCA patients with and those without PMR or GCA patients with and those without ischemic complications. CONCLUSION: Our findings show that the -592 C/A promoter polymorphism of the IL-10 gene is associated with susceptibility to GCA.     

Levothyroxine treatment in euthyroid pregnant women with autoimmune thyroid disease: effects on obstetrical complications

CONTEXT: Euthyroid women with autoimmune thyroid disease show impairment of thyroid function during gestation and seem to suffer from a higher rate of obstetrical complications. OBJECTIVE: We sought to determine whether these women suffer from a higher rate of obstetrical complications and whether levothyroxine (LT(4)) treatment exerts beneficial effects. DESIGN: This was a prospective study. SETTING: The study was conducted in the Department of Obstetrics and Gynecology. PATIENTS: A total of 984 pregnant women were studied from November 2002 to October 2004; 11.7% were thyroid peroxidase antibody positive (TPOAb(+)). INTERVENTION: TPOAb(+) patients were divided into two groups: group A (n = 57) was treated with LT(4), and group B (n = 58) was not treated. The 869 TPOAb(-) patients (group C) served as a normal population control group. MAIN OUTCOME MEASURES: Rates of obstetrical complications in treated and untreated groups were measured. RESULTS: At baseline, TPOAb(+) had higher TSH compared with TPOAb(-); TSH remained higher in group B compared with groups A and C throughout gestation. Free T(4) values were lower in group B than groups A and C after 30 wk and after parturition. Groups A and C showed a similar miscarriage rate (3.5 and 2.4%, respectively), which was lower than group B (13.8%) [P < 0.05; relative risk (RR), 1.72; 95% confidence interval (CI), 1.13-2.25; and P < 0.01; RR = 4.95; 95% CI = 2.59-9.48, respectively]. Group B displayed a 22.4% rate of premature deliveries, which was higher than group A (7%) (P < 0.05; RR = 1.66; 95% CI = 1.18-2.34) and group C (8.2%) (P < 0.01; RR = 12.18; 95% CI = 7.93-18.7). CONCLUSIONS: Euthyroid pregnant women who are positive for TPOAb develop impaired thyroid function, which is associated with an increased risk of miscarriage and premature deliveries. Substitutive treatment with LT(4) is able to lower the chance of miscarriage and premature delivery.