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101.
OBJECTIVES: To determine the seroprevalence of Helicobacter pylori infection among healthy children in eastern Turkey, to assess risk factors for seroconversion, and to assess the role of parental infection status in the transmission of H. pylori. METHODS: A commercial enzyme immunoassay test for IgG to H. pylori was used. Demographic information obtained included age, gender, socio-economic status and living conditions. RESULTS: One hundred and fifty-two (43.9%) of 346 children were seropositive. There was no significant difference in rates of seroprevalence between boys and girls (P > 0.05), but a significant rise was noted with increasing age (P < 0.001). We found a strong inverse correlation between family income and seropositivity (P < 0.001). Seroprevalence also varied significantly with the educational level of the mother (P < 0.001). There were no significant differences in seroprevalence associated with place of residence, water supply and the number of persons per room (P > 0.05). The prevalence of infection in the corresponding parents was 85.4% for mothers and 76.3% for fathers. Seroprevalence was higher in children whose mother was infected (P < 0.001). CONCLUSIONS: In eastern Turkey, as in other developing countries, H. pylori infection occurs early and increases with age. Infected parents, especially infected mothers, may have a important role in the transmission of H. pylori within families.  相似文献   
102.

Background/Aim

Transient tachypnea of the newborn (TTN) is a consequence of inadequate neonatal lung fluid clearance. Natriuretic peptides play an important role in the regulation of extracellular fluid volume. The aim of the study was to investigate the relation between plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels and TTN, and to find out its role in predicting disease severity.

Methods

A prospective controlled study involving 67 infants with TTN and 33 controls ≥ 34 weeks gestational age was conducted. Study and control groups were compared for plasma NT-proBNP levels measured on the 6th, 24th, 72nd and 120th hours of life. Cardiac systolic functions were evaluated by echocardiography.

Results

NT-proBNP levels were significantly higher in neonates with TTN compared to controls at 6th, 24th, 72nd and 120th hours (p < 0.001). NT-proBNP levels at 24th and 72nd hours were significantly higher in infants with prolonged tachypnea (p = 0.007 and p = 0.03) and in those who required respiratory support (p = 0.006 and p < 0.001). Tachypnea duration was correlated with NT-proBNP levels at 24 h (r = 0.41, p = 0.001). At a cut-off value of 6575 pg/ml, NT-proBNP had a sensitivity of 85% and specificity of 64% to predict mechanical ventilation requirement. Cardiac systolic functions were normal in all TTN patients.

Conclusion

Plasma NT-proBNP levels are increased in neonates with TTN. Measurement of plasma NT-proBNP can be useful for predicting infants who will have prolonged tachypnea and mechanical ventilation requirement.  相似文献   
103.
Image quality in non‐contrast‐enhanced (NCE) angiograms is often limited by scan time constraints. An effective solution is to undersample angiographic acquisitions and to recover vessel images with penalized reconstructions. However, conventional methods leverage penalty terms with uniform spatial weighting, which typically yield insufficient suppression of aliasing interference and suboptimal blood/background contrast. Here we propose a two‐stage strategy where a tractographic segmentation is employed to auto‐extract vasculature maps from undersampled data. These maps are then used to incur spatially adaptive sparsity penalties on vascular and background regions. In vivo steady‐state free precession angiograms were acquired in the hand, lower leg and foot. Compared with regular non‐adaptive compressed sensing (CS) reconstructions (CSlow), the proposed strategy improves blood/background contrast by 71.3 ± 28.9% in the hand (mean ± s.d. across acceleration factors 1–8), 30.6 ± 11.3% in the lower leg and 28.1 ± 7.0% in the foot (signed‐rank test, P < 0.05 at each acceleration). The proposed targeted reconstruction can relax trade‐offs between image contrast, resolution and scan efficiency without compromising vessel depiction. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
104.
We investigated the brainstem integrity in children with primary nocturnal enuresis (PNE) using auditory brainstem responses (ABR), blink reflex and exteroceptive suppression of the masseter muscle. We examined 23 children with PNE (16 male, 7 female; mean age: 10.4 years) and 19 control subjects (11 male, 8 female; mean age: 11.8 years). ABR parameters such as wave latencies, amplitudes and interpeak latencies and blink reflex parameters such as R1 and R2 amplitude and latencies were not significantly different between the 2 groups. Although S2 parameters of the exteroceptive suppression of the masseter muscle were easily and completely obtained from the control subjects, in the PNE group S2 onset latency and duration were not recorded in 26% of the study children (n = 6) (P = 0.01). S2 duration time was significantly lowered in the enuretic group (left side: P = 0.001 and right side: P = 0.003). S2 duration time changes in the enuretic group supports a possible brainstem dysfunction in children with PNE.  相似文献   
105.
We have used the single and dual color fluorescence in situ hybridization (FISH) technique combined with a new detection system, tyramide signal amplification (TSA), by using the multiple endocrine neoplasm type 1 (MEN1) gene and chromosome 11 specific alpha satellite DNA probes for the study of the allelic deletion of the MEN1 gene. The MEN1 gene is a new tumor suppressor gene and has been recently cloned on chromosome 11q13. FISH combined with the TSA detection system was performed on bone marrow interphase nuclei of 22 patients with acute myeloid leukemia (AML). The FISH-TSA analysis revealed the mono allelic deletion of the MEN1 gene in 4 out of 22 patients (18.18%), 2 of 9 AML-M2 patients (22.2%), 1 of 6 AML-M4 patients (16.6%), and 1 of 4 AML-M5 patients (25.0%). Our study indicates that allelic deletion of the MEN1 gene is not a major cause or a primary event in tumorigenesis of AML, although the long arm (q13 region) of chromosome 11 involves a chromosomal rearrangement in AML.  相似文献   
106.
Tuberous sclerosis is an autosomal dominant trait in which the dysregulation of cellular proliferation and differentiation results in the development of hamartomatous growths in many organs. The TSC2 gene is one of two genes determining tuberous sclerosis. Inactivating germline mutations of TSC2 in patients with tuberous sclerosis and somatic loss of heterozygosity at the TSC2 locus in the associated hamartomas indicate that TSC2 functions as a tumour suppressor gene and that loss of function is critical to expression of the tuberous sclerosis phenotype. The TSC2 product, tuberin, has a region of homology with the GTPase activating protein rap1GAP and stimulates the GTPase activity of rap1a and rab5a in vitro. Here we show that the region of homology between tuberin and human rap1GAP and the murine GAP mSpa1 is more extensive than previously reported and spans approximately 160 amino acid residues encoded within exons 34-38 of the TSC2 gene. Single strand conformation polymorphism analysis of these exons in 173 unrelated patients with tuberous sclerosis and direct sequencing of variant conformers together with study of additional family members enabled characterisation of disease associated mutations in 14 cases. Missense mutations, which occurred in exons 36, 37 and 38 were identified in eight cases, four of whom shared the same recurrent change P1675L. Each of the five different missense mutations identified was shown to occur de novo in at least one sporadic case of tuberous sclerosis. The high proportion of missense mutations detected in the region of the TSC2 gene encoding the GAP-related domain supports its key role in the regulation of cellular growth.   相似文献   
107.
Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular disease that affects the aorta, carotid, coronary and pulmonary arteries. Previous molecular genetic data have led to the hypothesis that SVAS results from mutations in the elastin gene, ELN. In these studies, the disease phenotype was linked to gross DNA rearrangements (35 and 85 kb deletions and a translocation) in three SVAS families. However, gross rearrangements of ELN have not been identified in most cases of autosomal dominant SVAS. To define the spectrum of ELN mutations responsible for this disorder, we refined the genomic structure of human ELN and used this information in mutational analyses. ELN point mutations co-segregate with the disease in four familial cases and are associated with SVAS in three sporadic cases. Two of the mutations are nonsense, one is a single base pair deletion and four are splice site mutations. In one sporadic case, the mutation arose de novo. These data demonstrate that point mutations of ELN cause autosomal dominant SVAS.   相似文献   
108.
Sepsis is a systemic inflammatory response to infection and a major cause of morbidity and mortality. Sildenafil (SLD) is a selective and potent inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase PDE5. We aimed to investigate the protective effects of sildenafil on caecal ligation and puncture (CLP)-induced sepsis in rats. Four groups of rats were used, each composed of 10 rats: (i) 10 mg/kg SLD-treated CLP group; (ii) 20 mg/kg SLD-treated CLP group; (iii) CLP group; and (iv) sham-operated control group. A CLP polymicrobial sepsis model was applied to the rats. All groups were killed 16 h later, and lung, kidney and blood samples were analysed histopathologically and biochemically. Sildenafil increased glutathione (GSH) and decreased the activation of myeloperoxidase (MPO) and of lipid peroxidase (LPO) and levels of superoxide dismutase (SOD) in the septic rats. We observed a significant decrease in LPO and MPO and a decrease in SOD activity in the sildenafil-treated CLP rats compared with the sham group. In addition, 20 mg/kg sildenafil treatment in the sham-operated rats improved the biochemical status of lungs and kidneys. Histopathological analysis revealed significant differences in inflammation scores between the sepsis group and the other groups, except the CLP + sildenafil 10 mg/kg group. The CLP + sildenafil 20 mg/kg group had the lowest inflammation score. Sildenafil treatment decreased the serum tumour necrosis factor (TNF)-α level when compared to the CLP group. Our results indicate that sildenafil is a highly protective agent in preventing lung and kidney damage caused by CLP-induced sepsis via maintenance of the oxidant-anti-oxidant status and decrease in the level of TNF-α.  相似文献   
109.
Recent studies have indicated that bone marrow stromal cells (BMSCs) have significant tropism towards glioma which makes them play an important role in carrying genes/drugs to inhibit the growth of glioma as cell vehicles. But BMSCs may differentiate into neural cells under entocranial environment and few researches support the idea that neurally differentiated bone marrow stromal cells (N-D-BMSCs) still hold the capacity of migrating to the tumor sites. The aim of our study was to investigate the tropism of N-D-BMSCs towards C6 glioma. In vitro migration assay was employed by transwell co-culture system and Student's t-test analysis indicated that N-D-BMSCs had the significant tropism towards C6 glioma-conditioned medium (GCM) (P < 0.01). Furthermore, the vascular endothelial growth factor (VEGF) bioactivity of the C6 GCM was neutralized by the anti-rat VEGF antibody and our data suggested that the VEGF from C6 GCM hold chemoattraction for N-D-BMSCs and some other cytokines from the C6 GCM may be responsible for the chemoattraction for N-D-BMSCs. In vivo migration assay was carried out with cells transplantation and one way ANOVA analysis indicated that the tropism of N-D-BMSCs towards C6 glioma sites presented time variation (P-value = 2.9E−20). Moreover, multiple comparisons for the time variables with the Student's t-test and the results suggested that the migration capacity of N-D-BMSCs towards C6 glioma sites reach the peak on the 7th day after transplantation. These results demonstrate that N-D-BMSCs as well as BMSCs have significant tropism towards C6 glioma.  相似文献   
110.

Introduction

Lower limb ischemia may cause nonhealing ulcers, infection, amputation and even mortality in diabetic patients. In this study, we review our data of ischemic lower limb revascularization procedures in diabetic patients and present the early, mid- and long-term results.

Material and methods

From March 2004 to September 2008, 83 patients with lower limb ischemia in Fontaine class III and IV underwent distal arterial bypass procedures. Saphenous vein grafts were used for below-knee arterial bypasses in all patients. In 16 (19%) patients femoropopliteal bypasses were performed with PTFE grafts. Short-term and long-term surgical results were evaluated.

Results

Ulcer recovery was determined in 36% of patients. Graft patency was 95% and 1 death (1%) occurred in short-term follow-up. In long-term follow-up the total effectiveness rate was 74%. Graft patency was 79% and 6 deaths (7%) occurred during the follow-up.

Conclusions

Lower limb ischemia is a serious event in patients with diabetes mellitus. The consequences may include increased mortality and morbidity in this particular patient population. However, distal arterial revascularizations are considerably effective procedures to avoid amputation, to eliminate symptoms, to promote ulcer recovery and to help the patient participate in social life with acceptable short, mid- and long-term follow-up results.  相似文献   
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