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1.
In most tissues, various cell membrane ion transporting systems are not fully developed and/or maximally active at the prenatal and early postnatal stage. Their progressive development and expression are a function of growth and maturity. We performed a multiple time-point study, in order to investigate the ability of a variety of tissues to maintain appropriate Ca++ and Mg++ homeostasis at different stages of postnatal development. Total intracellular Ca++ in one-week-old rat liver, brain and spinal cord tissues was significantly elevated, compared to mature animals. It increased further through the first three weeks of gestation. Intracellular Ca++ gradually and significantly declined in adult and mature animal groups. Alterations in total intracellular Mg++ of the same tissue samples, although not so profound, paralleled changes in total intracellular Ca++. We conclude that a developmental switch in intracellular Ca++ and Mg++ homeostasis occurs one to three weeks following birth. It might be related to the incomplete development of Ca++ and Mg++ transmembrane transporting systems, previously reported as being only partially expressed at the early postnatal stage. These developmental alterations in total intracellular Ca++ and Mg++ content might serve as a regulatory mechanism, adjusting cell activities to the physiological requirements of the growing and maturing animal.  相似文献   
2.
Pulmonary hypertension (PH) produces strain followed by hypertrophy and later dilatation of the right ventricle (RV) and pulmonary artery. The signs and symptoms are nonspecific. There is a need for a noninvasive sensitive way to diagnose PH. The purpose of this study is to evaluate phase abnormalities in radionuclide MUGA studies of patients with referred diagnosis of PH. In a retrospective analysis of 44 patients who had a radionuclide multigated study (MUGA) and contrast ventriculography (CV), 19 had high mean pulmonary pressure (over 20 mmHg) and a high pulmonary vascular resistance index (over 2.0). In 15 patients, a delayed phase segment in the RV corresponding to the pulmonary infundibulum and pulmonary conus was noted The Pulmonary Tongue sign (PT), 12 had PH (True positive) and 3 did not (false positive) on CV. No PT was seen in the remaining 29 patients, only 7 of them had PH (False negative). The sensitivity, specificity and accuracy of the PT sign in detecting PH was 80%, 72% and 77% respectively. The number of patients was too small to calculate the correlation of the grade of PT with the severity of PH. We conclude that The Pulmonary Tongue sign on a MUGA study is clinically useful in detecting PH.This project is supported by research project MLNO13 and funded by research Council, Kuwait University  相似文献   
3.
PurposeTo identify influence of different values of age and abnormal bowel length in HD patients selected for single stage TERPT which affects the technique of surgery.MethodsThis observational study was carried out for over 2.5 years. All children younger than 14 years old with clinical suspicion for HD, typical transitional zone (TZ) on contrast enema (CE) distal to splenic flexure, preoperative diagnosis approved by full thickness biopsy, no previous surgical history and no urgency were included. The distance between the anus and TZ was considered as aganglionic length on CE. Biopsy was taken from distal to proximal of resected bowel to reach circumferentially normal innervated bowel. Paired sample Student's t-test, Pearson correlation test, receiver operating characteristic (ROC) analysis were performed.ResultsForty-eight patients were enrolled in this study. Measured mean for aganglionic bowel length on CE and pathology were 33.5 ± 17.1 cm and 56.8 ± 33.5 cm, respectively (p < 0.01). Correlation coefficient (R) and coefficient of determination (R2) were 0.632 and 40%, respectively (p < 0.01). The difference between radiologic and pathologic measurements in females was higher than males (mean: 29.3 vs 21.9 cm) but was not statistically significant (p = 0.75). There was statistically significant difference between CE and pathologic results in the infants younger than 10 months (p = .004). Abnormal bowel length equal to 52 cm predicted requirement of laparoscopy assistance/laparotomy with 75% sensitivity and 85% specificity.ConclusionOur investigation showed it is safe to attempt for single stage TERPT when aganglionic length on CE is less than 52 cm and the child with HD is older than 10 months. Chance of requiring additional laparotomy or laparoscopy assistance is low in these patients.Type of studyStudy of diagnostic test.Level of evidenceLevel II.  相似文献   
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C4d immunostaining in the peritubular capillaries (PTC) is a marker of antibody-mediated rejection (AMR). We evaluated the histopathologic diagnoses of 388 renal transplant biopsies since the implementation of routine C4d immunostaining at our center. Of these, 155 (40%) biopsies had evidence of acute cellular rejection (ACR), out of which 119 (77%) had pure ACR, 31 (20%) had ACR with concomitant features of AMR, and five (3%) had ACR with focal C4d staining. Sixty-four (16%) biopsies exhibited features of AMR [33 (52%) pure AMR, and 31(48%) concomitant AMR and ACR]. One hundred and fifty-five (40%) biopsies had features of interstitial fibrosis and tubular atrophy (IFTA). Of these, 20 (13%) had concomitant AMR [13 (8.5%) had pure AMR and seven (4.5%) had concomitant ACR and AMR]. Creatinine at the time of biopsy was higher in patients with mixed ACR and AMR and the clinical behavior of mixed lesions is more aggressive over time. Despite having a lower serum creatinine at the time of biopsy, patients with IFTA experienced gradual decline in graft function over time. The pathologic findings in renal allograft biopsies are often mixed and mixed lesions appear to have more aggressive clinical behavior. These findings suggest the need for change in the Banff classification system to better capture the complexity of renal allograft pathologies.  相似文献   
8.
OBJECTIVE: There is conflicting evidence with regard to the impact of preoperative atrial fibrillation (AF) on the post mitral valve (MV) repair on the early and late outcome. METHODS: A total of 349 patients undergoing various MV repair procedures for degenerative mitral regurgitation (MR) between 1997 and 2003 were studied. Preoperatively, 152 (44%) of these patients were in AF and 197 (56%) patients were in sinus rhythm (SR). The clinical features and the outcome in these two cohorts of patients were compared. RESULTS: The patients in the AF group were older than their counterparts in the SR group (66+/-7 vs 62+/-9 years) (p=0.01), had a higher mean NYHA class score (2.4+/-0.6 vs 2.2+/-0.7) (p=0.04) and were more likely to have impaired left ventricular function (60% vs 36%) (p<0.0001). A similar proportion of patients in the AF (38%) and SR (30%) groups had additional cardiac surgical procedures (p=0.12). Operative mortality was 3.9% in AF group versus 0.5% in SR group (p=0.04), and operative morbidity was 27% versus 17%, respectively (p=0.03). At latest follow up, 4% of patients that were in SR preoperatively developed AF; conversely, 2% of the patients in the AF group converted to SR. The rates of recurrent grade II or III MR (4% vs 5%) (p=0.8) and MV re-operation (2.6% vs 2.5%) (p=1.0) were similar in the AF and SR groups. Kaplan-Meier survival at 7 years was 75+/-6% versus 90+/-3% (p=0.005). On Cox proportional hazards regression model, impaired LV function [(p=0.02), hazard ratio 0.25 (95% confidence intervals (C.I.) 0.078-0.84)] and AF [(p=0.03), hazard ratio 2.70 (95% C.I. 1.09-6.68)] were significant adverse predictors of survival. CONCLUSIONS: This study shows that in patients undergoing MV repair for degenerative MR, preoperative AF has a major negative impact on the early and late survival.  相似文献   
9.
It is a common algorithm for hand surgeons to diagnose and treat persistent post-traumatic wrist pain as complex regional pain syndrome (CRPS). Although it works for many patients, some conditions that affect the wrist don’t fall in this category and worsen with this treatment practice. We present a single-handed patient who had had a non-displaced distal radius fracture and was treated as CRPS for the next three months. He was eventually diagnosed with late tuberculous tenosynovitis of the wrist and a total wrist arthrodesis was performed. We believe that Mycobacterium tuberculosis infection should be in the differential diagnosis of persistent post-traumatic joint pain. This is especially important as Mycobacterium infections are becoming more common due to an increase in patients with chronic immunosuppression and definitive diagnosis and treatment of tuberculous tenosynovitis needs a high index of clinical suspicion.  相似文献   
10.

Background

To investigate the protective effect of 2-aminoethyl diphenylborinate (2-APB) against ischemia–reperfusion (I/R) injury in the rat kidney by an experimental study.

Materials and methods

Thirty male Sprague-Dawley rats were randomly divided into the following three groups: (1) sham group, (2) I/R group, and (3) I/R + 2-APB group. Renal I/R injury was induced by clamping the left renal pedicle for 45 min after right nephrectomy, followed by 3 h of reperfusion. The therapeutic agent 2-APB was administered intravenously at a dose of 2 mg/kg 10 min before renal ischemia. Glutathione, superoxide dismutase, total antioxidant capacity, malondialdehyde, tumor necrosis factor α, interleukin 6, aspartate aminotransferase, alanine aminotransferase, and creatinine levels were measured from blood samples, and the rats were sacrificed subsequently. Tissue samples were scored histopathologically. Visualization of apoptotic cells was performed using the terminal deoxynucleotidyl transferase dUTP nick end labeling staining method.

Results

2-APB significantly reduced serum malondialdehyde, tumor necrosis factor α, interleukin 6, aspartate aminotransferase, alanine aminotransferase, and creatinine levels in the I/R injury group. However, glutathione, superoxide dismutase, and total antioxidant capacity levels increased significantly. Histopathologic scores were significantly better and the rate of apoptosis was lower in the 2-APB group.

Conclusions

2-APB reduces oxidative stress and damage caused by renal I/R injury. The results of this study demonstrate that 2-APB can be used as an effective agent against I/R injury in the kidney.  相似文献   
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