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991.
Plastic bronchitis (PB), although a rare cause of airway obstruction, has mortalityrates up to 50% in children after Fontan-type cardiac surgery. We present the case ofan 18-month-old female patient with PB following pneumonia. At 6 months of age, thepatient underwent the Glenn procedure due to functionally univentricular heart.Fiberoptic bronchoscopy revealed complete blockage of the left bronchus by mucoidcasts. Pharmacotherapy consisted of glucocorticosteroids, azithromycin, and enalaprilmaleate. The child also received nebulized 3% NaCl solution, which proved to bebeneficial. In children submitted to Fontan-type procedures, physicians must be alertfor PB, which can be triggered by respiratory tract infection.  相似文献   
992.
Introduction:   Hafnia alveiis the only species of the genus Hafnia, which belongs to the family of Enterobacteriaceae. These Gram-negative bacteria are commonly distributed in the natural environment and are often the cause of human opportunistic infections. Their lipopolysaccharides (LPSs) are important surface antigens which are responsible for the serological specificity and numerous cross-reactions with other enterobacterial genera. So far, 29 different O-polysaccharide (OPS, O-antigen) structures in Hafnias LPSs have been established and for some of them the molecular basis of the serological activity has been elucidated. Materials and Methods:  OPS from H. alvei strain PCM 1219 was obtained by mild acid hydrolysis of the LPS followed by gel permeation chromatography of carbohydrate material on Sephadex G-50 column. The polysaccharide structure was determined using chemical methods as well as 13C NMR and 1H NMR spectroscopy. For serological studies, SDS-PAGE, immunoblotting, and passive hemagglutination tests were used. Results:  The serological studies revealed a cross-reactivity of the LPSs of H. alvei PCM 1219 and a group of H. alvei strains with an O-antigen containing D-glucose 1-phosphate and [(R)-3-hydroxybutyramido]-D-glucose. The following structure of the OPS was established: where Acyl stands for (R)-3-hydroxybutyryl and the degree of O-acetylation is ~70%. The structure of the core oligosaccharide was found to be typical of the genus Hafnia. Conclusions:  Based on the OPS structure and serological results it was concluded that H. alvei strain PCM 1219 should be classified in the same serogroup as the H. alvei type strain ATCC 13337 and five other strains containing D-glucose 1-phosphate and 2-deoxy-2-[(R)-3-hydroxybutyramido]-D-glucose in their O-antigens. Received: 2007.10.10, Accepted: 2008.06.30  相似文献   
993.
994.
995.

Background  

Glioblastomas are characterized by rapid cell growth, aggressive CNS infiltration, and are resistant to all known anticancer regimens. Recent studies indicate that fibrates and statins possess anticancer potential. Fenofibrate is a potent agonist of peroxisome proliferator activated receptor alpha (PPARα) that can switch energy metabolism from glycolysis to fatty acid β-oxidation, and has low systemic toxicity. Fenofibrate also attenuates IGF-I-mediated cellular responses, which could be relevant in the process of glioblastoma cell dispersal.  相似文献   
996.

Introduction

Rotavirus (RV) infection is the most common cause of gastroenteritis in children. This paper identifies the most common genotypes of rotaviruses isolated from children hospitalized with gastroenteritis and attempts to determine any relationship between infection with a certain rotavirus genotype.

Material and methods

The investigated group consisted of 68 consecutive children with rotavirus gastroenteritis (confirmed by an agglutination test). Rotavirus genotype was determined in stool samples obtained from each child.

Results

The P[9]VP4 genotype was observed in 41/61 positive samples (over 67.2%) that were permanently associated with the G3 VP7 genotype. Moreover, G3 was determined as the most commonly isolated G type (77.94%). As well as the P[9]G3 type, G3 was also found in the P[4] type (5 cases). Twenty-six out of 61 (42.6%) children in whom rotavirus genotype was determined were co-infected with pathogenic bacteria. No statistical correlation was observed between rotavirus P[9]G3 gastroenteritis and digestive tract co-infection with pathogenic bacteria (p > 0.05). Elevated ALT activity was found in 34/59 (57.6%) cases of rotavirus gastroenteritis. Elevated ALT serum level was found to correlate with P[9]G3 rotavirus genotype but concomitant infections did not.

Conclusions

The most common genotype of rotaviruses observed in our group of children, P[9]G3, has rarely been described. Co-infection of the digestive tract with pathogenic bacteria and elevated serum ALT concentrations were found to be the most frequent phenomena. A correlation between P[9]G3 rotavirus genotype and elevated serum ALT level was found, but no significant relationship was identified between concomitant infections and P[9]G3 genotype.  相似文献   
997.
Mitochondrial DNA was found to be highly mutated in colorectal cancer cells. One of the key molecules involved in the maintenance of the mitochondrial genome is the nuclear‐encoded polymerase gamma. The aim of our study was to determine if there is a link between polymorphisms within the polymerase gamma gene (POLG) and somatic mutations within the mitochondrial genome in cancer cells. We investigated POLG sequence variability in 50 colorectal cancer patients whose complete mitochondrial genome sequences were determined. Relative mtDNA copy number was also determined. We identified 251 sequence variants in the POLG gene. Most of them were germline‐specific (~92%). Twenty‐one somatic changes in POLG were found in 10 colorectal cancer patients. We have found no association between the occurrence of mtDNA somatic mutations and the somatically occurring variants in POLG. MtDNA content was reduced in patients carrying somatic variants in POLG or germline nucleotide variants located in the region encoding the POLG polymerase domain, but the difference did not reach statistical significance. Our findings suggest that somatic mtDNA mutations occurring in colorectal cancer are not a consequence of somatic mutations in POLG. Nevertheless, POLG nucleotide variants may lead to a decrease in mtDNA content, and consequently result in mitochondrial dysfunction.  相似文献   
998.
Preterm neonates are susceptible to infection due to a combination of sub-optimal immunity and increased exposure to invasive organisms. Mannose-binding lectin (MBL) is a component of the innate immune system, which may be especially important in the neonatal setting. The objective of this study was to investigate the impact of MBL on susceptibility and severity of infection in preterm neonates during their first month of life. One hundred fifty eight preterm neonates were genotyped for MBL mutations by heteroduplex analyses. Consecutive serum MBL levels were measured by ELISA and clinical and laboratory data, including blood cultures, were collected for each baby. A third of the premature neonates had genetically determined MBL deficiency. In addition, MBL levels were also low in the first week of life and lower in neonates with a wild type genotype who were less than 28 wk gestation or a birth weight of less than 1000 g, thereby increasing the number of neonates with a low MBL level at birth. MBL deficiency was associated with an increased risk of sepsis (p < 0.01). This study indicates that MBL levels are low in neonates at birth and renders premature neonates to an increased risk of infection.  相似文献   
999.
AIM: To establish the influence of the Trp64Arg variant of the beta3-adrenergic receptor (Trp64Arg- beta3AR) on body mass index (BMI) and insulin resistance (IR) in obese children. METHODS: BMI, presence of the Trp64Arg mutation, plasma glucose and insulin concentrations during an oral glucose tolerance test (OGTT) and IR were determined in 60 obese and 33 normal weight children. RESULTS: The frequency of Trp64Arg was similar in normal weight and obese children. BMI, glucose and insulin concentrations during an OGTT in children with Trp64Argbeta3AR were not different from those with Trp64Trpbeta3AR. IR was confirmed in 42.8% of children with Trp64Argbeta3AR and in 45.6% of children with Trp64Trpbeta3AR (NS). CONCLUSIONS: 1. The similar frequency of the Trp64Argbeta3AR variant in normal weight and obese children suggests that it is not a susceptibility gene for obesity in Polish children. 2. The presence of the Trp64Argbeta3AR variant does not have an unfavourable influence on BMI, glucose or insulin concentrations during OGTT or on IR frequency in Polish obese children.  相似文献   
1000.
OBJECTIVES: The efficacy of antenatal steroid therapy (ANS--use with the recommendation from 1999; therapy repeated every 7-10 days; dexamethasone was used) on the incidence of RDS in neonates born before 34 weeks of gestation has been well documented in several studies. However, we know very little about the influence of ANS on patent ductus arteriosus (PDA). DESIGN: The purpose of this study was to assess the influence of ANS on the incidence of PDA in neonates born before 35 weeks of gestation. MATERIALS AND METHODS: The analysed population consisted of 425 newborns delivered at Research Institute Polish Mother's Memorial Hospital between 1996-1998. Patients were enrolled in three groups according to mode of ANS: Group I--complete ANS; Group II--partial ANS; Group III--without ANS (reference group, OR = 1). The complete ANS consisted of at least 24 mg of dexamethasone with a first dose given not earlier then 24 hours before delivery. The analysis was based on retrospective evaluation of patient's medical records. PDA was diagnosed during echocardiographic examination or during autopsy. The incidence and risk of significant PDA in enrolled groups were estimated. RESULTS: Use of complete ANS has no influence of the incidence of PDA. In the partial ANS group the risk of PDA (OR 1,89; p = 0,052 vs group III) was increased. Risk of PDA was also higher in patients born before 29 weeks of gestation, especially from the partial ANS group. CONCLUSIONS: The antenatal steroid therapy has influence of the incidence of PDA. We observed higher risk of PDA in the group of neonates born before 29 weeks of gestation and in the partial ANS group.  相似文献   
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