Epigenetic profile of testicular germ cell tumours

DNA methylation is the best known and most thoroughly studied epigenetic mechanism. Hypermethylation of CpG islands associated with silencing of tumour suppressor genes or tumour-related genes is a common hallmark of human cancer. The list of tumour-related genes with aberrant hypermethylation in their CpG islands has been increasing. There is also the potential for using DNA methylation profile data as markers for various types of human cancer. In this paper, we review the methylation profile of testicular germ cell tumours (TGCTs). We show that TGCTs have distinctive DNA methylation profiles that differ from those of somatic tissue-derived cancers or somatic tissues. We also discuss the methylation profile of TGCTs in terms of the DNA reprogramming that occurs in primordial germ cells or pre-implantation embryos. Finally, we describe the potential clinical utility of this unique methylation phenotype in TGCTs with regard to developing a novel tumour marker. These data suggest that unmethylated DNA fragments in TGCTs may have diagnostic implications. Further elucidation of epigenetic profiles in TGCTs is expected to provide a new insight into the biology of this disease.     

Laparoscopic choledochotomy in management of choledocholithiasis

PURPOSE: Laparoscopic choledochotomy on patients indicated for common bile duct exploration was carried out according to an algorithm for managing choledocholithiasis. This study describes retrospectively our method and evaluates a new cystic duct biliary decompression cannula (J-tube) as an alternative to the T-tube. METHODS: Patients with confirmed choledocholithiasis (n=46) underwent laparoscopic choledochotomy. The T-tube was inserted in cases with suspected retained stones after common bile duct clearance, and the J-tube (950-mm long, 4 Fr) with a tapered and J-shaped segment at the distal end was inserted in other cases. RESULTS: Only 1 case was converted to open surgery (success rate, 97.8%); the J-tube was inserted in 30 patients and the T-tube in 15. The median operation time, hospital stay, and the interval until removal of the tube were significantly shorter with J-tube than with T-tube cases. Bile leakage after surgery occurred in 4 J-tube and 2 T-tube cases with one residual stone in each case. CONCLUSIONS: The transcystic decompression tube is easily and safely inserted with the J-kit. Among several strategies currently available for the management of choledocholithiasis, laparoscopic choledochotomy with the use of the J-tube is one of the safest and most feasible methods.     

Analysis of heat generation of lithium ion rechargeable batteries used in implantable battery systems for driving undulation pump ventricular assist device

We have developed internal battery systems for driving an undulation pump ventricular assist device using two kinds of lithium ion rechargeable batteries. The lithium ion rechargeable batteries have high energy density, long life, and no memory effect; however, rise in temperature of the lithium ion rechargeable battery is a critical issue. Evaluation of temperature rise by means of numerical estimation is required to develop an internal battery system. Temperature of the lithium ion rechargeable batteries is determined by ohmic loss due to internal resistance, chemical loss due to chemical reaction, and heat release. Measurement results of internal resistance (R(cell)) at an ambient temperature of 37 degrees C were 0.1 Omega in the lithium ion (Li-ion) battery and 0.03 Omega in the lithium polymer (Li-po) battery. Entropy change (DeltaS) of each battery, which leads to chemical loss, was -1.6 to -61.1 J/(mol.K) in the Li-ion battery and -9.6 to -67.5 J/(mol.K) in the Li-po battery depending on state of charge (SOC). Temperature of each lithium ion rechargeable battery under a discharge current of 1 A was estimated by finite element method heat transfer analysis at an ambient temperature of 37 degrees C configuring with measured R(cell) and measured DeltaS in each SOC. Results of estimation of time-course change in the surface temperature of each battery coincided with results of measurement results, and the success of the estimation will greatly contribute to the development of an internal battery system using lithium ion rechargeable batteries.     

A restricted subarachnoid hemorrhage in the cortical sulcus in cerebral amyloid angiopathy: could it be a warning sign?

BACKGROUND: Cerebral amyloid angiopathy is a well-known disease that is predominantly recognized in elderly people and repeatedly causes large subcortical hemorrhages. These hemorrhages may be derived from vessel wall weakness because of Abeta depositions in the wall of the cortical and leptomeningeal arteries. Although vessel ruptures in CAA have been thought to occur in cortical arteries, it was recently demonstrated that the primary hemorrhage occurs in the subarachnoid space, particularly the cerebral sulci, as a result of multiple ruptures of meningeal arteries in some cases of subcortical hematoma caused by CAA. CASE DESCRIPTION: Case patient 1 was a 74-year-old woman who presented with epileptic seizure. A restricted SAH in the right frontal lobe was observed on MRI. Thirty-three days later, left hemiparesis occurred suddenly and a huge subcortical hematoma was observed in the right frontal lobe on CT. The hematoma was removed, and the patient was pathologically diagnosed with amyloid angiopathy. Case patient 2 was a 73-year-old man who presented with epileptic seizure. A restricted SAH in the right frontal lobe was observed on MRI. Twenty days later, left hemiparesis occurred suddenly and a huge subcortical hematoma was observed in the right frontoparietal area on CT. Hematoma removal was performed on both patients, and they were diagnosed pathologically with amyloid angiopathy. CONCLUSIONS: We report on the cases of 2 patients with CAA who presented with epileptic seizure and were found to have a restricted subarachnoid hematoma in the cerebral sulcus on MRI before their subcortical hemorrhages occurred. Both cases were diagnosed pathologically. This demonstrated that vessel ruptures in CAA can occur in the subarachnoid space, particularly the cerebral sulci, as a result of ruptures of meningeal arteries. A restricted SAH on CT/MRI could be a warning sign of a huge subcortical hemorrhage in CAA.     

Locally applied cilostazol suppresses neointimal hyperplasia and medial thickening in a vein graft model.

BACKGROUND: Pathological changes in vein grafts begin immediately after arterial circulation is applied to the grafts. Chemical mediator stimulation and mechanical strain induce neointimal hyperplasia and medial thickening of the vein grafts, resulting in their failure. We investigated the inhibitory effect of locally applied cilostazol, an inhibitor of cyclic adenosine monophosphate phosphodiesterase III, on neointimal hyperplasia and medial thickening of the grafts. METHODS AND RESULTS: We established a distal anastomotic stricture model of femoral vein-abdominal aorta interposition grafting in rats. In this model, neointimal hyperplasia was observed not only at the distal anastomotic sites, but also in the graft body at postoperative day 14 and was markedly progressed at day 28. A strong expression of tenascin-C was found in the media and neointima of the graft body. In the grafts around which cilostazol was administered locally using Pluronic gel, neointimal hyperplasia was significantly suppressed compared with control grafts treated with the gel alone, with the mean neointimal cross-sectional area reduced by 87.1% for the graft body and by 78.9% for the distal anastomotic sites and mean medial cross-sectional area of the graft body reduced by 54.2% at day 28 versus the control. Cilostazol treatment decreased cell proliferation and the number of tenascin-C-producing cells seen by in situ hybridization, but the expression of tenascin-C protein was not suppressed. CONCLUSION: We concluded that a single perivascular application of cilostazol inhibits neointimal hyperplasia and medial thickening of vein grafts in a rat model.     

Laparoscopic repair of late-presenting Bochdalek hernia in 2 infants

Laparoscopic repair was performed on 2 infants with late-presenting Bochdalek hernia. Intraoperatively, the entire small intestine was herniated in 1 case and the stomach, small intestine, and part of the colon and spleen were herniated in the other case. Laparoscopic repair of Bochdalek hernia was successfully completed in both the cases. On the basis of our experience, 4 points seem important in laparoscopic surgery for Bochdalek hernia: (1) avoiding damage to the spleen while reducing organs back into the abdominal cavity; (2) ensuring visualization of diaphragmatic defect after reducing the spleen and intestinal tract; (3) ensuring sufficient width to suture the dorsal side of the diaphragm; and (4) identifying intestinal malrotation. We believe that the fourth point represents an advantage of a laparoscopic approach, which seems superior to the thoracoscopic approach and could represent a useful therapy for Bochdalek hernia in infants and older patients.     

Renal adenoma treated with partial nephrectomy: a case report

We report a case of renal adenoma which was diagnosed as renal cell carcinoma preoperatively. A 78-year-old man, who had been under observation for bladder cancer for 4 years, was incidentally found to have a small right renal tumor at follow-up computed tomography (CT). Enhanced CT demonstrated a tumor which was hypervascular, 10 x 10 mm size, at the lower pole of the right kidney. There was no evidence of distant metastasis. The preoperative diagnosis was renal cell carcinoma, cT1aN0M0, and we performed right partial nephrectomy. The histopathorogical finding was renal adenoma. Renal adenomas are benign tumors and not uncommon in autopsy cases. However, when they are detected clinically, it is difficult to distinguish them from renal cell carcinoma preoperatively.     

Convenience of the computed tomography perfusion method for cerebral vasospasm detection after subarachnoid hemorrhage

BACKGROUND: Vasospasm is a frequent complication in the early clinical course after SAH. Although various methods have been used to measure cerebral perfusion including PET, SPECT, xenon CT, and TCD, these require the patients to remain still for a long period. In addition, TCD is operator dependent. The current study aimed to clarify the convenience of CTP for the assessment of cerebral vasospasm caused by SAH. METHODS: Nineteen patients with SAH aged 44 to 85 years (mean, 64 years) were recruited with informed consent. All patients were treated with the prevailing therapy and underwent CTP on days 6 to 9, followed by DSA and 3D-CTA to detect cerebral vasospasm. In each patient, we measured the MTT, CBF, and CBV. The reliability of CTP data was verified by comparing the data from CTP and xenon CT between the controls, and the average was calculated. Six ROIs were located symmetrically in the frontal, temporal, and occipital lobes. RESULTS: An MTT value more than 20% greater than the average indicated the progression of cerebral vasospasm, and patients with vasospasm-related infarcts exhibited an MTT more than 47% greater than the mean value (odds ratio, 50). Patients with delayed cerebral infarcts had a significantly lower mean CBF and CBV and higher MTT than patients who did not develop CI. CONCLUSION: Significant correlations between MTT and CBF values and neurovascular findings were obtained. Computed tomography perfusion can be performed in a short time and on a regular basis, and it therefore has the potential to identify cerebral vasospasm because of SAH.     

Prognostic value of changes in spinal cord signal intensity on magnetic resonance imaging in patients with cervical compressive myelopathy

Background contextSignal intensity on preoperative cervical magnetic resonance imaging (MRI) of the spinal cord has been shown to be a potential predictor of outcome of surgery for cervical compressive myelopathy. However, the prognostic value of such signal remains controversial. One reason for the controversy is the lack of proper quantitative methods to assess MRI signal intensity.PurposeTo quantify signal intensity and to correlate intramedullary signal changes on MRI T1- and T2-weighted images (WIs) with clinical outcome and prognosis.Study designRetrospective case study.Patient samplePatients (n=148; cervical spondylotic myelopathy, n=102 and ossified posterior longitudinal ligament, n=46) who underwent surgery for cervical compressive myelopathy and had high signal intensity change on sagittal T2-WI MRI before surgery between 2006 and 2010.Outcome measureNeurologic assessment was conducted with the Japanese Orthopedic Association (JOA) scoring system for cervical myelopathy. The rate of neurologic improvement was calculated with the use of preoperative and postoperative JOA scores.MethodsQuantitative analysis of MRI signal on both T1- and T2-WIs via use of the signal intensity ratio (SIR; signal intensity of lesion relative to that at C7-T1 disc level) was performed. Correlations between SIR on T1- and T2-WIs and preoperative JOA score, JOA improvement rate, disease duration, and MRI morphologic classification (cystic or diffuse type) were analyzed. Multivariate regression analysis for JOA improvement rate was also analyzed. In a substudy, 25 patients underwent follow-up MRI starting from 6 months after surgery to analyze the relationship between changes in SIR on follow-up MRI and clinical outcome.ResultsSIR on T1-WIs, but not SIR on T2-WIs, correlated with postoperative neurologic improvement. The disease duration correlated negatively with SIR on T1-WIs and JOA improvement rate but not with SIR on T2-WIs. SIR on T2-WIs of “cystic type” was significantly greater than of “diffuse type,” but SIR on T1-WI and JOA improvement rate were not different in the two types. Stepwise multivariate regression analysis indicated that SIR on T1-WIs and long disease duration were significant predictors of postoperative neurologic outcome. SIR on follow-up T1-WI and changes in SIR on T1-WI after surgery correlated positively with postoperative improvement rate. SIR on follow-up T2-WI and changes on T2-WI correlated negatively with postoperative neurologic improvement.ConclusionsOur results suggest that low intensity signal on preoperative T1-WIs but not T2-WIs correlated with poor postoperative neurologic outcome. Furthermore, decreased signal intensity on postoperative T1-WIs and increased signal intensity on postoperative T2-WIs are predictors of poor neurologic outcome.     

Free air on CT and the risk of peritonitis in peritoneal dialysis patients: a retrospective study

Background: Intra-abdominal free air is found frequently in patients undergoing peritoneal dialysis (PD). Some studies have investigated an association between intra-abdominal free air and peritonitis in PD patients. However, most used chest X-rays, which are of limited sensitivity, and the association was not made clear. We conducted a retrospective study of the association between peritonitis and intra-abdominal free air using computed tomography. Methods: The presence and volume of free air, and its relationship with other variables, were assessed on review of routine examinations in 108 patients. Correlations between the presence of free air and age, duration of PD, continuous ambulatory versus automated PD, presence or absence of a person who assisted in bag changes, exit-site infection, tunnel infection and peritonitis were assessed. Results: Free air was detected in 29 patients (27.1%). The prevalence of peritonitis was higher in the free air (+) group than in the free air (?) group: 1/40.2 patient-months for free air (+) versus 1/96.9 patient-months for free air (?). The risk ratio of free air for peritonitis was 2.41 (95% confidence interval: 2.28–2.55) and was similar when corrected for age, gender, albumin, diabetes mellitus and body mass index. Conclusion: Free air is an independent risk factor for peritonitis in PD patients. This suggests that bag change procedures should be re-evaluated, and patients re-educated, when necessary.