Imaging and retention measurements of selenium 75 homocholic acid conjugated with taurine,and the carbon 14 glycochol breath test to document ileal dysfunction due to late radiation damage

In order to assess ileal dysfunction in patients with complaints after pelvic radiation therapy, retention measurements and scintigraphic imaging with selenium 75 homocholic acid conjugated with taurine (⁷⁵Se-HCAT), combined with the carbon 14 glycochol breath test, were evaluated in 39 patients. In 22 patients without ileal resection the results of the⁷⁵Se-HCAT test and the breath test differentiated between a normal functioning ileum (both tests negative) and ileal dysfunction as a cause of complaints (one or both tests positive). Among the patients with ileal dysfunction, the combination of both tests permitted those with bacterial overgrowth (breath test positive,⁷⁵Se-HCAT negative) to be separated from patients with evidence of bile acid malabsorption (⁷⁵Se-HCAT positive, breath test positive or negative). In 17 patients with small-bowel resection, the⁷⁵Se-HCAT test helped to estimate the severity of bile acid malabsorption with implications for therapy. In this group the breath test was false-negative in 7 cases with abnormal⁷⁵Se-HCAT. Additional systematically performed scintigraphic imaging improved the accuracy of the⁷⁵Se-HCAT test, revealing cases with prolonged colonic accumulation of the radiopharmaceutical, causing spurious retention values. In conclusion, assessment of ileal dysfunction by nuclear medicine techniques in post-irradiation conditions provides information about the aetiology and therefore the possibility of adjustment in the clinical management. Offprint requests to: R.A. Valdes Olmos     

Technetium-99m dimercaptosuccinic acid and ifosfamide tubular dysfunction in children with cancer

Quantitative ^99mTc-dimercaptosuccinic acid (^99mTc-DMSA) renal scintigraphy was used to asses ifosfamide-induced changes in renal function in 11 children who received chemotherapy for various malignancies. Serial measurements of absolute ^99mTc-DMSA renal uptake, calculated on conjugated views, were performed during and after chemotherapy. Data of 37 studies obtained before and at different cumulative dose levels of ifosfamide were analysed in relation to clinical and biochemical parameters. A highly significant relationship between ^99mTc-DMSA uptake and cumulative ifosfamide dose was found (P<0.001). The most frequently observed abnormal pattern on scintigraphic images was decreased kidney uptake together with increased accumulation in bladder. ^99mTc-DMSA uptake was more consistent than ₂-microglobulin values in urine and more sensitive than quantitative hyperaminoaciduria and tubular resorption of phosphate for the detection of ifosfamide-induced tubular dysfunction. ^99mTc-DMSA uptake was decreased in both patients with and patients without clinical toxicity. Persistently reduced ^99mTc-DMSA uptake was observed in four patients during follow-up; in one of them, who was asymptomatic after ifosfamide therapy, sudden onset of Fanconi syndrome was observed when he was retreated with carboplatin 1 year later. It is concluded that ^99mTc-DMSA renal scintigraphy is a suitable method to assess progressive ifosfamide-induced tubular injury whereas scintigraphic imaging is helpful for interpreting renal uptake changes. The test is able to detect subclinical injury and may potentially predict high risk at retreatment.     

Virtual Reality Exposure Therapy for PTSD Vietnam Veterans: A Case Study

Virtual reality (VR) integrates real-time computer graphics, body tracking devices, visual displays, and other sensory input devices to immerse a participant in a computer-generated virtual environment that changes in a natural way with head and body motion. VR exposure (VRE) is proposed as an alternative to typical imaginal exposure treatment for Vietnam combat veterans with posttraumatic stress disorder (PTSD). This report presents the results of the first Vietnam combat veteran with PTSD to have been treated with VRE. The patient was exposed to two virtual environments, a virtual Huey helicopter flying over a virtual Vietnam and a clearing surrounded by jungle. The patient experienced a 34% decrease on clinician-rated PTSD and a 45% decrease on self-rated PTSD. Treatment gains were maintained at 6-month follow-up.     

Endorectal coil MRI in local staging of rectal cancer

PURPOSE: The choice of the therapeutic strategies in patients affected with rectal cancer is strictly dependent by the tumor stage. So, in order to obtain an improvement in preoperative staging accuracy, new imaging modalities are now under investigation. The aim of this work is the evaluation of endorectal-coil MRI in the local staging of rectal cancer. MATERIAL AND METHODS: Fourty-three patients affected with histologically proven rectal cancer, have been evaluated by an high-field strength magnet (1.5 T). In 14/43 patients neoadjuvant pre-operative chemotherapy had been previously performed. In all cases axial SE T1w and FSE T2w sequences and coronal or sagittal FSE T2w sequences, with and without fat suppression, were performed. Basing upon the TNM staging system and the previously reported MRI signs the local extent of the tumor was evaluated, focusing about the rectal wall infiltration and the perirectal lymph nodes involvement. All the patients underwent surgery and a comparative evaluation of MRI and pathological staging was done. RESULTS: At MRI the tumor was detected in 38/43 patients. In evaluating wall infiltration the MRI results agreed with pathological results in 89% of patients and showed 92% accuracy in T1-T2 stage and 94% in T3. In evaluating perirectal lymph nodes metastases MRI showed 69% accuracy, 82% sensitivity and 55%specificity. DISCUSSION AND CONCLUSIONS: The poor accuracy of CT and body-coil MRI in evaluating wall involvement in patients with rectal cancer is mainly related to their inability to demonstrate the single layers of the rectal wall. So transrectal ultrasound is now the first choice modalitiy in local staging of rectal cancer. However transrectal ultrasound showed low sensitivity in detecting perirectal lymph nodes metastases and low accuracy in evaluating the patients previously undergone to neoadjuvant chemotherapy or radiotherapy. On the other hand the improvement of MRI sequences and the availability of the endorectal coils allowed to visualize the single layers of the rectal wall so making the endorectal-coil MRI a reliable imaging technique to stage rectal cancer. The results of our work demonstrate a good diagnostic accuracy of endorectal-coil MRI in local staging of rectal cancer, in particular the degree of rectal wall infiltration was well demonstrated, while the perirectal lymph nodes metastases were demonstrated with less accuracy. The long examination time, the costs and the movement-related artefacts are the main limits of MRI. In particular the movement-related artifacts sometime do not allow the visualization of the wall layers so lowering the diagnostic accuracy in demonstrating the tumor wall infiltration. In conclusion, even though endorectal coil MRI proved to be a reliable imaging technique in local staging of rectal cancer, at present we are not able to state what may be its real role in diagnostic evaluation of the patients with rectal cancer, in particular if compared to endorectal ultrasound. Further, comparative studies, based upon larger patients series are probably needed to draw a definitive conclusion.     

Restoration of cardiomyocyte functional properties by angiotensin II receptor blockade in diabetic rats

Recent evidence suggests that blockade of the renin-angiotensin system ameliorates diabetes-induced cardiac dysfunction, but the mechanisms involved in this process remain elusive. We investigated the effect of treatment with an angiotensin II receptor blocker, losartan, on the metabolic and electrophysiological properties of cardiomyocytes isolated from streptozotocin-induced diabetic (STZ) rats. Glucose uptake and electrophysiological properties were measured in ventricular cardiomyocytes from normoglycemic and STZ-induced diabetic rats given vehicle or 20 mg x kg(-1) x day(-1) losartan for 8 weeks. Insulin and beta-adrenergic stimulation failed to increase the glucose uptake rate in STZ cardiomyocytes, whereas the alpha-adrenergic effect persisted. Concurrently, a typical prolongation of action potential duration (APD) and a decrease of transient outward current (I(to)) were recorded in patch-clamped STZ myocytes. Treatment with losartan did not affect body weight or glycemia of diabetic or control animals. However, in losartan-treated STZ-induced diabetic rats, beta-adrenergic-mediated enhancement of glucose uptake was completely recovered. APD and I(to) were similar to those measured in losartan-treated control rats. A significant (P < 0.0001) correlation between metabolic and electrophysiological parameters was found in control, diabetic, and losartan-treated diabetic rats. Thus, angiotensin receptor blockade protects the heart from the development of cellular alterations typically associated with diabetes. These data suggest that angiotensin receptor blockers may represent a new therapeutic strategy for diabetic cardiomyopathy.     

Bioimpedance analysis highlights changes in body composition at the early stages of impairment of kidney transplant function.

OBJECTIVE: Kidney transplantation restores renal filtration, although it does not achieve the function of 2 native kidneys, and with time it may involute back to chronic renal failure. We hypothesized that bioelectrical impedance analysis (BIA) might highlight differences for body compartments among kidney transplants (Tx) with different filtration rates. METHODS: Thirty transplantation patients (19 male, 11 female) were studied at 62.4+/-26.6 months postsurgery and were divided into 3 groups: good creatinine clearance (crCl, mL/min/1.73 m2; >65.0), borderline (35.0相似文献   

Minimum internal diameter of the greater saphenous vein is an important determinant of successful femorodistal bypass grafting that is independent of the quality of the runoff

The greater saphenous vein is assessed as part of the workup for femorodistal bypass surgery in our unit. The aim of this study was to determine whether the minimum internal diameter (MID) of the vein predicted graft patency and limb salvage in femorodistal bypass surgery, independently of the quality of the runoff. A consecutive series of 67 infrainguinal vein bypass grafts were performed on 62 patients with critical lower limb ischemia. All were followed for at least 1 year. The MID of the greater saphenous vein was calculated from preoperative saphenograms, and all of the arteriograms were scored for their runoff using an ad hoc method approved by the Society for Vascular Surgery. The cumulative patency of all vein grafts at 3 years was 59 +/- 7% (SE), and the limb salvage was 85 +/- 5%. All femoropopliteal bypass grafts were patent at 3 years if the MID of the vein was greater than 3.0 mm. The crural bypass patency was 66 +/- 12% for an MID greater than 3.0 mm and only 27 +/- 12% for an MID less than 3.0 mm. Every extra point on the runoff score increased the hazard of bypass failure by 16% (95% CI 1.0-34; p < .05). Vein diameter and runoff score were independent of one another (r2 = -.106). The MID of the greater saphenous vein is a major determinant of outcome in infrainguinal vein bypass surgery independent of the arterial runoff.     

Limited Left Thoracotomy for Reoperative Coronary Artery Bypass Grafting without Cardiopulmonary Bypass for Circumflex Grafting in Patients with Patent Internal Thoracic Artery Graft

Abstract Background: We describe our experience with the limited left thoracotomy strategy for reoperative coronary artery bypass graft (CABG)to the circumflex coronary artery system, emphasizing the indications, our particular operative technique, and early clinical follow-up. Methods: From January 2001 to January 2002, 8 consecutive patients underwent redo revascularization via limited left thoracotomy and without cardiopulmonary bypass. This operation was indicated for patients with recurrent myocardial ischemia confined to the lateral wall of the left ventricle, especially if a patent left internal thoracic artery (LITA)-to-left anterior descending coronary artery (LAD)graft was present. Results: All 8 patients underwent successful redo revascularization via limited left thoracotomy. Eight patients received 14 saphenous vein grafts (mean 1.7 grafts/patient). No instances of postoperative myocardial infarction or death occurred. During a follow-up period ranging from 1 to 12 months (mean, 5. 2 months), all patients were asymptomatic and without evidence of ischemia or infarction. Conclusions: For select patients who have patent LITA grafted into the LAD and who need redo CABG to the coronary artery circumflex system, the limited left thoracotomy approach without cardiopulmonary bypass is a safe operation and a less invasive alternative to repeat sternotomy and conventional CABG.     

Exome Sequence Data From Multigenerational Families Implicate AMPA Receptor Trafficking in Neurocognitive Impairment and Schizophrenia Risk

Schizophrenia is a mental disorder characterized by impairments in behavior, thought, and neurocognitive performance. We searched for susceptibility loci at a quantitative trait locus (QTL) previously reported for abstraction and mental flexibility (ABF), a cognitive function often compromised in schizophrenia patients and their unaffected relatives. Exome sequences were determined for 134 samples in 8 European American families from the original linkage study, including 25 individuals with schizophrenia or schizoaffective disorder. At chromosome 5q32–35.3, we analyzed 407 protein-altering variants for association with ABF and schizophrenia status. For replication, significant, Bonferroni-corrected findings were tested against cognitive traits in Mexican American families (n = 959), as well as interrogated for schizophrenia risk using GWAS results from the Psychiatric Genomics Consortium (PGC). From the gene SYNPO, rs6579797 (MAF = 0.032) shows significant associations with ABF (P = .015) and schizophrenia (P = .040), as well as jointly (P = .0027). In the Mexican American pedigrees, rs6579797 exhibits significant associations with IQ (P = .011), indicating more global effects on neurocognition. From the PGC results, other SYNPO variants were identified with near significant effects on schizophrenia risk, with a local linkage disequilibrium block displaying signatures of positive selection. A second missense variant within the QTL, rs17551608 (MAF = 0.19) in the gene WWC1, also displays a significant effect on schizophrenia in our exome sequences (P = .038). Remarkably, the protein products of SYNPO and WWC1 are interaction partners involved in AMPA receptor trafficking, a brain process implicated in synaptic plasticity. Our study reveals variants in these genes with significant effects on neurocognition and schizophrenia risk, identifying a potential pathogenic mechanism for schizophrenia spectrum disorders.Key words: schizophrenia, cognition, SYNPO, WWC1, synaptic plasticity