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21.
22.
Background and study aimsSince the introduction of liver transplantation (LTx) in children suffering from liver failure in 1963, many centres around the world have offered this service to children that have no other alternative. The aim of this retrospective study is to analyse the results of paediatric liver transplant in Kuwait over the last decade.Patients and methodsA retrospective chart review was done involving paediatric patients during the time period of 1995–2004. The information collected included patient demographics, indications for liver transplantation, survival of both patient and allograft, and complications.ResultsA total of 16 cases were found and analysed. The mean age was 3.6 years (ranged 5 months–17 years). There were nine boys and seven girls. The most common indications for LTx were biliary atresia and metabolic liver disease. All the liver transplants were done abroad. There were totally nine deceased donor and seven living related cases. The complications were acute cellular rejection in five, hypertension in two, biliary complications in four, cytomegalovirus (CMV) infection in three and post lymphoproliferative disease in two cases. All but one patient are presently alive.ConclusionThe above information demonstrates that LTx in Kuwati children is safe and improves the quality of life for those that would otherwise have no other alternative.  相似文献   
23.
Small Heat Shock Proteins (sHSPs) are a diverse family of molecular chaperones that prevent protein aggregation by binding clients destabilized during cellular stress. Here we probe the architecture and dynamics of complexes formed between an oligomeric sHSP and client by employing unique mass spectrometry strategies. We observe over 300 different stoichiometries of interaction, demonstrating that an ensemble of structures underlies the protection these chaperones confer to unfolding clients. This astonishing heterogeneity not only makes the system quite distinct in behavior to ATP-dependent chaperones, but also renders it intractable by conventional structural biology approaches. We find that thermally regulated quaternary dynamics of the sHSP establish and maintain the plasticity of the system. This extends the paradigm that intrinsic dynamics are crucial to protein function to include equilibrium fluctuations in quaternary structure, and suggests they are integral to the sHSPs’ role in the cellular protein homeostasis network.  相似文献   
24.

Background  

Neutrophil elastase level/activity is elevated in a variety of diseases such as atherosclerosis, systolic hypertension and obstructive pulmonary disease. It is unknown whether obese individuals with prehypertension also have elevated neutrophil elastase, and if so, whether it has a deleterious effect on pulmonary function. Objectives: To determine neutrophil elastase levels in obese prehypertensive women and investigate correlations with pulmonary function tests.  相似文献   
25.

Objectives

To evaluate the safety of using the stiff end of a coronary wire to perforate an atretic pulmonary valve (PV) in patients with pulmonary atresia with intact ventricular septum (PAIVS).

Background

Radiofrequency perforation is an accepted modality to perforate the PV in patients PAIVS. However, the high cost precludes its widespread use.

Patients and methods

This is a single-center experience that spanned from March 2013 to January 2016 and involved 13 neonates who were severely cyanotic with PAIVS and with ductal-dependent pulmonary circulation. The stiff end of a coronary wire was used to perforate the atretic PV anterogradely, followed by balloon pulmonary valvuloplasty.

Results

The mean age of patients was 3.9?±?2.7?days and their mean weight was 2.8?±?0.19?kg. The mean oxygen saturation was 77.1?±?3.2%. All had membranous pulmonary atresia, with patent infundibulum and tripartite right ventricle. The valve was successfully perforated in 11 out of 13 patients. Death occurred in two patients (15.4%) owing to heart failure and sepsis. Patent ductus arteriosus stenting was performed 2?days after the procedure in one patient because of cyanosis followed by one and half ventricle repair at of age 5?months. Two patients (15.4%) had one and a half ventricle repair at age of 5?months and 6?months owing to insufficient anterograde pulmonary flow. Two patients (15.4%) underwent second intervention with balloon dilatation of the valve. The remaining seven patients (53.8%) had no further intervention. Two cases (15.4%) had femoral artery thrombosis treated with streptokinase. The mean duration of follow-up was 13.17?±?7?months. There was significant improvement in the degree of tricuspid incompetence. There was a significant growth in the tricuspid valve annulus during the follow-up (the mean Z score increased from ?0.8?±?0.9 to 0.1?±?0.9) (p?=?0.003). There was also a significant increase in the tricuspid valve annulus/mitral valve annulus ratio as its mean increased from 0.73?±?0.10 to 0.86?±?0.11 during follow-up (p?<?0.001).

Conclusion

Perforation of the atretic PV in selected cases with membranous atresia and patent infundibulum using the stiff end of a coronary wire is an effective alternative to using radiofrequency perforation.  相似文献   
26.

Background

Systemic sclerosis (SSc) is an autoimmune connective tissue disease with vascular, fibrotic and immune changes of skin and some internal organs. Anti-heterogeneous nuclear ribonucleoproteins (anti-hnRNP) were found in SSc patients.

Aim of the work

To assess anti-hnRNP A1 and A2 autoantibodies in limited SSc patients and to find their relation to clinical and hand radiographic characteristics.

Patients and methods

26 limited SSc patients and 16 matched control were studied. Skin thickness was scored according to the modified Rodnan skin score method (mRss) and radiologic examination by plain X-ray of the hand and wrist was performed anti-hnRNP A1 and A2 were measured in patients and control.

Results

All patients were females with a mean age of 37.5 ± 11.24 years and mean disease duration of 7.84 ± 1.19 years. 96.2% of cases showed juxta-articular osteoporosis, 38.5% with marginal erosions, 73.1% with surface erosions, 42.3% with subchondral cyst, 42.3% with metacarpophalangeal subluxation, 11.5% with marginal sclerosis, 80.8% with resorption of distal phalanges, 38.5% with resorption of distal ulna and 34.6% with calcinosis. Anti-hnRNPA1 was positive in all the patients but the anti-hnRNPA2 was positive in 21 (80.8%). Anti-hnRNP A1 and A2 showed significant difference between patients and control (5.66 ± 4.18 ng/ml vs 2.88 ± 0.82; p < 0.01 and 1.82 ± 0.36 vs 0.73 ± 0.08; p < 0.02, respectively). There was no significant correlation between the markers with the mRss or radiographic changes.

Conclusion

Joint affection in SSc is more frequent than expected. Anti-hnRNP A1 and anti hnRNP A2 antigens may be useful markers for SSc patient although no significant relation was found with radiologic findings.  相似文献   
27.

Background and study aims

Hepatitis C virus (HCV) infection is a severe problem among patients on maintenance haemodialysis who are at particular risk for blood-borne infections because of prolonged vascular access and potential for exposure to contaminated equipment. Occult hepatitis C virus infection (OCI) is defined as the presence of HCV RNA in liver or peripheral blood mononuclear cells (PBMCs) in the absence of detectable HCV antibody or HCV RNA in the serum. In this study, we aimed to investigate the existence of occult hepatitis C virus infection in PBMCs of haemodialysis (HD) patients in one center. Moreover, we tried to link the condition to risk factors associated with HCV infection in those patients.

Patients and methods

We included 40 patients with renal diseases undergoing regular haemodialysis who were repeatedly anti-HCV negative. HCV RNA detection was tested by Quantitative Real time PCR in serum and PBMCs.

Results

The results of this study revealed that 23% of our haemodialysis patients have occult hepatitis C virus infection. There was a highly significant increase in ALT levels in patients with OCI versus the negative group. Also, there is a significant increase of history of blood transfusion in patients with occult HCV (p?=?0.03) while the duration of haemodialysis showed no statistical significant difference between both groups. The viral load of the occult hepatitis C virus infection subjects ranged from 581to 74,307 copies/ml.

Conclusion

These results highlight the potential risk of hepatitis C virus transmission from patients within haemodialysis units in Egypt. Isolation of patients on dialysis machines depending on the results of hepatitis serological markers is not enough. Testing for hepatitis C virus -RNA in peripheral blood mononuclear cells is more reliable in identifying patients with an OCI when a liver biopsy is not available.  相似文献   
28.
Chlorinated pesticide residues in human breast milk from five southern Jordan districts were analyzed in 2012/2013. The total number of samples from all districts was 100. The number of samples gathered from each district was collected according to their population densities. The present study shows that 59% of the samples which contained pesticides’ residues were p,p’-DDE, 30% contained β-HCH, 10% contained p,p′-DDT, 6% contained α-HCH, 2% contained heptachlor and 1% contained endrin. These human milk samples were free of aldrin, dieldrin, α-endosulfan, β-endosulfan, HCB, γ-HCH, o,p′-DDD, o,p′-DDT and o,p′-DDE. The levels of the six mentioned compounds detected in all mother’s milk samples were higher in Ghor El-Safi district compared with the other four districts. In this study, it is recommended to continue the pesticides residues monitoring in all parts of Jordan, particularly in Ghor El-Safi district and other regions in the cultivated Jordan Valley.  相似文献   
29.
OBJECTIVES

This study examined: 1) the impact of myectomy on postoperative mitral regurgitation (MR) and 2) the association between the severity of MR and the left ventricular outflow tract (LVOT) gradient.

BACKGROUND

For patients with hypertrophic obstructive cardiomyopathy (HOCM) and MR, controversy exists as to whether myectomy alone is sufficient in eliminating MR. Furthermore, the relationship between the degree of MR and the LVOT peak gradient has not been well defined.

METHODS

We performed pre- and postoperative transthoracic as well as intraoperative transesophageal studies in 104 consecutive patients with HOCM undergoing septal myectomy. Left ventricular outflow tract gradient and the nature of MR were assessed.

RESULTS

In the 93 patients without independent mitral valve disease, a relationship was observed between MR severity and the LVOT gradient. Left ventricular outflow tract gradient (mean ± standard deviation) for trivial, mild, moderate and severe MR were: 23.2 ± 19.1, 43.8 ± 25.4, 70.1 ± 21.0 and 104 ± 21.0 mm Hg (p < 0.001). Early postoperative, MR was absent or trivial in 80%, mild in 19% and moderate in 1%. None of these patients required additional mitral valve surgery. For patients with independent mitral valve disease (n = 11), five required mitral valve surgery as well as myectomy. The remainder had significant reductions in the degree of MR with myectomy alone.

CONCLUSIONS

For patients with HOCM and MR not due to independent mitral valve disease, myectomy significantly reduced the degree of MR, without requirement for additional mitral valve surgery. In these patients the severity of MR was directly related to the magnitude of the LVOT gradient.  相似文献   

30.
OBJECTIVE: To analyse profiles of coronary artery flow velocity at rest in patients with aortic stenosis and to determine whether changes of the coronary artery flow velocities are related to symptoms in patients with aortic stenosis. DESIGN: A prospective study investigating the significance of aortic valve area, pressure gradient across the aortic valve, systolic left ventricular wall stress index, ejection fraction, and left ventricular mass index in the coronary flow velocity profile of aortic stenosis; and comparing flow velocity profiles between symptomatic and asymptomatic patients with aortic stenosis using transoesophageal Doppler echocardiography to obtain coronary artery flow velocities of the left anterior descending coronary artery. SETTING: Tertiary referral cardiac centre. PATIENTS: Fifty eight patients with aortic stenosis and 15 controls with normal coronary arteries. RESULTS: Adequate recordings of the profile of coronary artery flow velocities were obtained in 46 patients (79%). Left ventricular wall stress was the only significant haemodynamic variable for determining peak systolic velocity (r = -0.83, F = 88.5, P < 0.001). The pressure gradient across the aortic valve was the only contributor for explaining peak diastolic velocity (r = 0.56, F = 20.9, P < 0.001). Controls and asymptomatic patients with aortic stenosis (n = 12) did not differ for peak systolic velocity [32.8 (SEM 9.7) v 27.0 (8.7) cm/s, NS] and peak diastolic velocity [58.3 (18.7) v 61.9 (13.5) cm/s, NS]. In contrast, patients with angina (n = 12) or syncope (n = 8) had lower peak systolic velocities and higher peak diastolic velocities than asymptomatic patients (P < 0.01). Peak systolic and diastolic velocities were -7.7 (22.5) cm/s and 81.7 (17.6) cm/s for patients with angina, and -19.5 (22.3) cm/s and 94.0 (20.9) cm/s for patients with syncope. Asymptomatic patients and patients with dyspnoea (n = 14) did not differ. CONCLUSIONS: Increased pressure gradient across the aortic valve and enhanced systolic wall stress result in characteristic changes of the profile of coronary flow velocities in patients with aortic stenosis. Decreased or reversed systolic flow velocities are compensated by enhanced diastolic flow velocities, particularly in patients with angina and syncope. This characteristic pattern of the profile of coronary artery flow velocities in patients with angina or syncope may be useful for differentiating those patients from asymptomatic patients.  相似文献   
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