External quality control of Mycobacterium tuberculosis drug susceptibility testing: results of two rounds in endemic countries.

SETTING: Quality assurance for the World Health Organization (WHO)/International Union Against Tuberculosis and Lung Disease (The Union) global tuberculosis (TB) drug resistance surveillance programme. OBJECTIVE: To monitor the quality of drug susceptibility testing (DST) in different countries. METHODS: In 2002-2003 and 2005-2006, 20 Mycobacterium tuberculosis strains were sent by the WHO/Union Supranational Reference Laboratory of Rome to TB reference laboratories in Albania, Bahrain, Kosovo, Mozambique, Oman, Qatar and Turkey for external quality control (EQC). RESULTS: In 2002-2003, the specificity, sensitivity, efficiency, reproducibility and predictive values for resistance/susceptibility were >or=90% for streptomycin (SM), isoniazid (INH) and ethambutol (EMB). In 2005-2006, all statistical values were >or=96% for SM, INH, rifampicin and EMB. CONCLUSION: EQC improved the quality of M. tuberculosis DST in the participating countries.     

Evidence of pancreatic neuropathy and neuropathic pain in hereditary chronic pancreatitis

Increased neural density and neural hypertrophy are characteristic features of pancreatic neuropathy in chronic pancreatitis. Here, we present the extraordinary case of prominent pancreatic neuropathy in a 21-year-old female patient with hereditary chronic pancreatitis and intractable pain who underwent total pancreatectomy. The histopathological analysis demonstrated remnant pancreatic tissue which was only composed of prominent intrapancreatic nerves and fibrosis, without any visible remaining functional pancreatic parenchyma. These histological alterations, including nerve hypertrophy and increased neural density, are known for different aetiologies of chronic pancreatitis, e.g. alcoholic, idiopathic and tropic pancreatitis. However, this is the first report of a patient with hereditary chronic pancreatitis demonstrating the characteristic features of pancreatic neuropathy and neuropathic pain.     

Visfatin concentration is decreased in women with gestational diabetes mellitus in the third trimester

Our aim is to investigate visfatin concentration and its relationship to glycated hemoglobin (HbA1c), insulin resistance, lipid parameters, and neonatal birth weight in women with gestational diabetes mellitus (GDM). In our study group, there were 47 women with GDM and 31 women with normal glucose tolerance (NGT) between 33-39 weeks of gestation. Plasma visfatin levels were significantly decreased in pregnant women with GDM compared to those with NGT (p=0.001). Homeostasis model assessment-insulin resistance (HOMA-IR) levels were higher in the GDM group than in the NGT group (p=0.006). In all subjects, plasma visfatin levels were negatively correlated with HOMA-IR, post-prandial blood glucose, triglycerides, and VLDL cholesterol (p<0.05). We did not observe any statistically significant correlation between the plasma visfatin levels and the selected parameters in the GDM group, but in the NGT group plasma visfatin levels were negatively correlated with HOMA-IR (r=-0.36, p=0.04). There was no correlation between visfatin concentrations and fetal birth weight in either group (p>0.05). By regression analysis, having GDM was found to be the only significant determinant (t=3.5, p=0.001) of visfatin concentration (R=0.39, r2=0.15). We conclude that women with GDM have significantly decreased visfatin concentrations in the third trimester. Future studies are required to establish the exact role of visfatin in the pathogenesis of GDM.     

Identification of hypoglycaemic compounds from berries of Juniperus oxycedrus subsp. oxycedrus through bioactivity guided isolation technique

Ethnopharmacological relevance

Decoction of Juniperus oxycedrus subsp. oxycedrus L. (Cupressaceae) berries is used internally as tea and pounded fruits are consumed to lower blood glucose levels in Turkey.

Aim of the study

To evaluate hypoglycaemic and antidiabetic activity of J. oxycedrus subsp. oxycedrus berries and to identify active compounds through bioactivity guided isolation technique.

Material and methods

Hypoglycaemic effect of J. oxycedrus subsp. oxycedrus (Joso) berry extracts on oral administration was studied using in vivo models in normal, glucose-hyperglycaemic rats. Streptozotocin induced diabetic rats were used to examine antidiabetic activity of Joso extracts, subextracts, fractions, subfractions and shikimic acid (SA).

Results

Through in vivo bioactivity-guided fractionation processes, shikimic acid, 4-O-β-d-glucopyranosyl ferulic acid and oleuropeic acid-8-O-β-d-glucopyranoside were isolated from the n-butanol subextract by silica gel and reverse phase column chromatography as the main active ingredient of the active subfraction. After 8 days administration of the major compound shikimic acid, blood glucose levels (24%), malondialdehyde levels in kidney tissues (63-64%) and liver enzymes (AST, ALT, ALP) of diabetic rats were decreased.

Conclusion

Results indicated that Joso berry extract and its active constituents might be beneficial for diabetes and its complications.     

Human leukocyte antigen class II alleles and dental caries in a child population

PURPOSE: The purpose of this study was to investigate a possible relationship between human leukocyte antigens (HLAs) DRB1 and DQB1, dental caries, and colonization by mutans streptococci (MS) in children. METHODS: Sixty children were clinically examined for caries in accordance with World Health Organization criteria and methods. Thereafter, subjects were assigned into 2 groups: (1) high-caries children (dft and DMFT > or = 5); and (2) caries-free children (dft and DMFT = 0). Fresh saliva samples were collected and testedfor mutans streptococci, after which the subjects were placed into 2 groups, having either high (> or =10(5) colony-forming units [CFU]/mL saliva) or low (< 10(5) CFU/mL saliva) numbers of micro-organisms in saliva. The polymerase chain reaction/sequence specific primer method was used to determine HLA DNA typing from fresh blood samples. RESULTS: There was no significant difference between the frequency of HLA alleles in high-caries and caries-free subjects. Although chi-square test suggested an association for HLA-DRB1*01 and HLA-DQB1*03 with the salivary numbers of MS (P = .026 and P = .009, respectively), these could not be confirmed by logistic regression analysis (P = .188 and P = .101, respectively). CONCLUSIONS: The results obtained fail to establish an association between human leukocyte antigen alleles DRB1 and DQB1 and salivary numbers of MS in the selected child population.     

Surface hardness evaluation of different composite resin materials: influence of sports and energy drinks immersion after a short-term period

Objectives:

This study evaluated the effect of sports and energy drinks on the surface hardness of different composite resin restorative materials over a 1-month period.

Material and Methods:

A total of 168 specimens: Compoglass F, Filtek Z250, Filtek Supreme, and Premise were prepared using a customized cylindrical metal mould and they were divided into six groups (N=42; n=7 per group). For the control groups, the specimens were stored in distilled water for 24 hours at 37º C and the water was renewed daily. For the experimental groups, the specimens were immersed in 5 mL of one of the following test solutions: Powerade, Gatorade, X-IR, Burn, and Red Bull, for two minutes daily for up to a 1-month test period and all the solutions were refreshed daily. Surface hardness was measured using a Vickers hardness measuring instrument at baseline, after 1-week and 1-month. Data were statistically analyzed using Multivariate repeated measure ANOVA and Bonferroni''s multiple comparison tests (α=0.05).

Results:

Multivariate repeated measures ANOVA revealed that there were statistically significant differences in the hardness of the restorative materials in different immersion times (p<0.001) in different solutions (p<0.001). The effect of different solutions on the surface hardness values of the restorative materials was tested using Bonferroni''s multiple comparison tests, and it was observed that specimens stored in distilled water demonstrated statistically significant lower mean surface hardness reductions when compared to the specimens immersed in sports and energy drinks after a 1-month evaluation period (p<0.001). The compomer was the most affected by an acidic environment, whereas the composite resin materials were the least affected materials.

Conclusions:

The effect of sports and energy drinks on the surface hardness of a restorative material depends on the duration of exposure time, and the composition of the material.     

二维、三维超声技术检测正常胎儿胸腺的研究

目的 建立胎儿胸腺二维各径线和三维体积的正常值,并比较胎儿胸腺的二维、三维超声测量.方法 采集567例正常胎儿胸腺的二维超声测值,包括最大横径、前后径、上下径、最大横截面积及三维超声体积.结果 567例胎儿中541例胎儿满意获得胎儿胸腺的最大横径、前后径、上下径和最大横截面积和体积.胎儿胸腺二维各径线、三维体积均随孕周的增加而增加,与孕周均呈直线相关,三维体积与孕周的相关性明显高于二维超声测值(P＜0.05).结论 本研究建立了胎儿胸腺二维超声面积、周长、直径、横径和三维超声体积的正常参考值.三维超声测量胎儿胸腺体积与孕周相关性更高,提示较二维超声测量更为准确.

Abstract：

Objective To establish the normative data of the 2D and 3D ultrasound (US)measurements of the developing fetal thymus and comparing the 2DUS and 3DUS measurements of the fetal thymus. Methods The normal fetuses' thymus of 567 cases were assessed, and maximum transverse diameter(MTD),antero posterior diameter (APD), suprainferior diameter (SID), maximum transverse area (MTA) were measured by 2DUS,and thymic volume(TV) was measured by 3DUS. Results 2DUS,3DUS assessments of the fetal thymic MTD, APD, SID, MTA and TV were possible in 541 of 567 normal singletons. The fetal thymic 2D diameters/area and 3D volume grow with the gestational age(GA) in linear correlation. The 3D-US TV measurements and GA was significantly higher than that of any individual 2DUS measurements and GA ( P ＜0.05). Conclusions This study presents the normative data of the 2DUS and 3DUS measurements of the developing fetal thymus. 3DUS fetal thymus volume is more significantly correlated to GA than the other 2DUS measurements, which indicates 3DUS measurement of the fetal thymus is more accurate than that of 2DUS.     

A unified framework for cross-modality multi-atlas segmentation of brain MRI

Multi-atlas label fusion is a powerful image segmentation strategy that is becoming increasingly popular in medical imaging. A standard label fusion algorithm relies on independently computed pairwise registrations between individual atlases and the (target) image to be segmented. These registrations are then used to propagate the atlas labels to the target space and fuse them into a single final segmentation. Such label fusion schemes commonly rely on the similarity between intensity values of the atlases and target scan, which is often problematic in medical imaging – in particular, when the atlases and target images are obtained via different sensor types or imaging protocols.In this paper, we present a generative probabilistic model that yields an algorithm for solving the atlas-to-target registrations and label fusion steps simultaneously. The proposed model does not directly rely on the similarity of image intensities. Instead, it exploits the consistency of voxel intensities within the target scan to drive the registration and label fusion, hence the atlases and target image can be of different modalities. Furthermore, the framework models the joint warp of all the atlases, introducing interdependence between the registrations.We use variational expectation maximization and the Demons registration framework in order to efficiently identify the most probable segmentation and registrations. We use two sets of experiments to illustrate the approach, where proton density (PD) MRI atlases are used to segment T1-weighted brain scans and vice versa. Our results clearly demonstrate the accuracy gain due to exploiting within-target intensity consistency and integrating registration into label fusion.     

Mucopolysaccharidosis type I (Hurler syndrome): oral and radiographic findings and ultrastructural/chemical features of enamel and dentin.

Mucopolysaccharidosis type I (Hurler syndrome, MPS I-H) is an autosomal recessive inborn error of metabolism due to deficient alpha-L-iduronidase enzyme activity and is characterized by accumulation of incompletely degraded glycosaminoglycans that generally lead to impairment of organ and body functions. This report presents oral, dental, and radiographic findings in a boy who presented with MPS I-H. Nine of the patient's primary teeth were extracted and investigated using scanning electron microscopy, x-ray diffraction analysis, and Fourier transform infrared spectroscopy. Compared with the teeth of otherwise healthy patients, MPS I-H-affected dentin was characterized by extremely narrow dentinal tubules, whose direction followed an irregular wave-like pattern. The enamel-dentin junction was defective, as evidenced by microgaps, and the enamel displayed irregular arrangement of prisms. The additional novel observation was made that the protein structure of enamel and dentin changed in MPS I-H-affected teeth. Also, an increase was observed in the relative mineral/matrix ratio of MPS I-H-affected dentin, indicating that its protein content had decreased in comparison with normal dentin.     

Non-atopic asthma in children is related to maternal bronchial hyperreactivity

Data on the pathogenic mechanisms underlying the development of non-atopic asthma in children are scarce. Our aim was to evaluate the association and compare the atopic status, pulmonary functions, bronchial hyperresponsiveness and serum total immunoglobulin E (IgE) levels of parents of atopic and non-atopic asthmatic children by using objective methods. Fifty-one asthmatic children aged 4–16 yr and their parents were included into the study. Initially the American Thoracic Society's Respiratory Disease questionnaire inquiring data on symptoms of asthma, rhinitis and past medical history was filled in. Afterwards, skin prick test with aeroallergens, pulmonary function and methacholine bronchial provocation tests and serum sampling for total IgE level determinations were carried out. Bronchial hyperresponsiveness to methacholine was significantly more common in the mothers of non-atopic children compared to those of atopic ones, although no significant difference was observed in the skin prick test reactivity, pulmonary function test parameters and serum IgE levels. Questionnaire data revealed that the presence of asthmatic symptoms such as wheezing and phlegm and doctor-diagnosed asthma were more common in the mothers of non-atopic children. Meanwhile, asthmatic symptoms were also found to be significantly more common in fathers of non-atopic children. Logistic regression analyses revealed that maternal PC₂₀ was the only predictive factor for the risk of displaying non-allergic asthma in children. The results demonstrate that among the risk factors studied, maternal bronchial hyperreactivity was associated with the development of asthma in non-atopic children.