Comparison of short inversion time inversion recovery (STIR) and fat-saturated (chemsat) techniques for background fat intensity suppression in cervical and thoracic MR imaging

The purpose of this study was to compare short inversion time inversion recovery (STIR) fast spin-echo (FSE), and fat-saturated T2-weighted FSE sequences in terms of uniformity of fat suppression and lesion conspicuity for magnetic resonance (MR) imaging of the neck and thorax. STIR FSE and fat-saturated T2-weighted FSE images were scored for uniformity of fat suppression (n = 40) and lesion conspicuity (n = 35). Five-point rank score analyses were utilized by three experienced radiologists. The mean scores of STIR and fat-saturated FSE techniques for uniformity of fat suppression were 4.3 and 2.3, respectively (P < 0.0001). The mean scores of STIR and fat-saturated FSE techniques for lesion conspicuity were 4.2 and 3.5, respectively (P < 0.0001). Insufficient fat suppression was prominent in the mandible, supraclavicular region, anterior mediastinum, epipericardial fat, and subdiaphragmatic fat. In addition, fat-saturated T2-weighted FSE showed inadvertent water suppression in 25%. The STIR FSE technique was superior to the fat-saturated FSE technique for cervical and thoracic MR imaging.     

Preferred and Energetically Optimal Transition Speeds During Backward Human Locomotion

Some aspects of backward locomotion are similar to forward locomotion, while other aspects are not related to their forward counterpart. The backward preferred transition speed (BPTS) has never been directly compared to the energetically optimal transition speed (EOTS), nor has it been compared to the preferred transition speed (PTS) during forward locomotion. The purpose of this study was to determine whether the BPTS occurs at the EOTS, and to examine the relationship between the backward and forward preferred gait transition speeds. The preferred backward and forward transition speeds of 12 healthy, young subjects (7 males, 5 females) were determined after subjects were familiarized with forward and backward treadmill locomotion. On a subsequent day, subjects walked backward at speeds of 70, 80, 90, 100, and 110% of the BPTS and ran backward at speeds of 60, 75, 90, 100, and 120% of the BPTS while VO₂ and RPE data were collected. After subtracting standing VO₂, exercise VO₂ was normalized to body mass and speed. For each subject, energy-speed curves for walking and running were fit to the normalized data points. The intersection of these curves was defined as the EOTS which was compared to the BPTS using a paired t-test (p < 0.05). RPE and VO₂ at the BPTS were also compared between walking and running conditions, and the correlation between BPTS and PTS was calculated. The EOTS (1.85 ± 0.09 m·s^-1) was significantly greater than the BPTS (1.63 ± 0.11 m·s^-1). Even though RPE was equal for walking and running at the BPTS, VO₂ was significantly greater when running. There was a strong correlation (r = 0.82) between the BPTS and the PTS. Similar to forward locomotion, the determinants of the BPTS must include factors other than metabolic energy. The gait transition during backward locomotion exhibits several similarities to its forward counterpart.

Key Points

• The backward preferred transition speed (1.63 ± 0.11 m·s^-1) was significantly less than the energetically optimal transition speed (1.85 ± 0.09 m·s^-1), similar to what is observed during forward locomotion.
• RPE was equal for walking and running at the backward preferred transition speed.
• There was a strong correlation (r = 0.82) between the backward and forward preferred transition speeds.
• Similar to forward locomotion, the determinants of the BPTS must include factors other than metabolic energy.

Key Words: Running, walking, gait transition, preferred transition speed     

Acinar cell carcinoma of the pancreas with intraductal growth: Report of a case

Acinar cell carcinomas (ACCs) of the pancreas are rare neoplasms, accounting for approximately 1% of all exocrine pancreatic tumors. This type of tumor is known to be aggressive, although the survival rates are somewhat better than they are for ductal carcinoma. The tumor tends to present nonspecific symptoms. It occurs in older patients, and jaundice is infrequent. This report presents a case of ACC of the pancreas with intraductal papillary growth and lymph node metastasis.     

A new method for establishing an intrapulmonary tumor in the rabbit

Objectives: Local treatments against malignant intrapulmonary tumors, such as radiotherapy, photodynamic therapy, and laser ablation therapy, are sometimes used in preference to surgery or chemotherapy. The efficacy of such treatments is dependent not only on the pathological type of the primary tumor, but also on loco-regional settings such as location of the lesion and relationship between the tumor and surrounding organs as well as tissues. Therefore, in order to evaluate the efficacy of a newly developed local treatment, it is essential to have a model in which a tumor can be established at an intended location. In this study, we developed a model for the establishment of an intrapulmonary tumor, using the rabbit.Methods: After induction of general anaesthesia, a catheter was inserted via the airway into the lung of a Japanese wiite rabbit, under X-ray guidance. The lung was then inoculated with a collagen gel matrix containing a suspension of VX2 cells derived from rabbit skin squamous cell carcinoma. Subsequent tumor growth was evaluated with X-ray imaging and pathological examination.Results: Growth of a solitary tumor at the arget site was pathologically confirmed in 9 of 12 rabbits that were inoculated with 1×10⁸ cells. In addition, tumor growth could be followed in 8 of 9 rabbits by chest X-ray examination. That is, a solitary intrapulmonary tumor could be established in 8 of 12 animals (67%).Conclusion: The rabbit model reported here enables establishment of a solitary intrapulmonary tumor and thus can provide a suitable experimental setting for evaluation of local treatments of intrapulmonary tumors.     

The impairment of hepatocytes and sinusoidal endothelial cells during cold preservation in rat fatty liver induced by alcohol and the beneficial effect of hepatocyte growth factor

A fatty liver resulting from alcohol intake is often unattractive for grafting. In this study, we investigated the impairment of hepatocytes and sinusoidal endothelial cells (SECs) during cold preservation of alcohol-induced fatty liver and examined the efficacy of human recombinant hepatocyte growth factor (hrHGF). Rats were fed an alcohol diet. We performed histological examinations of the hepatocytes and observed the ultrastructural alteration of the SECs. Additionally, we measured hepatic transaminase and peroxidative lipids for hepatocellular injury and the hyaluronic acid uptake rate (HUR) to determine SEC injury. We added hrHGF to University of Wisconsin (UW) solution to assess the protective effect of the agent. Numerous fatty deposits were observed in ethanol-induced fatty livers. These grew with the duration of cold storage. Hepatic transaminases of the effluents increased during cold preservation in the livers of alcohol-treated rats. Additionally, peroxidative lipids in the effluents increased during cold preservation in the livers of alcohol-treated rats, whereas they were undetectable in non-alcohol-treated rat livers. The sinusoidal endothelium had severely deteriorated in the livers of alcohol-treated rats. Further, the HUR decreased with ethanol treatment and/or cold preservation. The addition of hrHGF suppressed the increase of hepatic transaminase in the effluent of cold-preserved alcohol-treated livers. Peroxidative lipids in the same effluents were undetectable. In fatty livers, both hepatocytes and SECs received severe damage during cold preservation. Furthermore, we demonstrated that hepatocellular injury was significantly inhibited by hrHGF.     

Risk factors for acute rejection in living donor liver transplantation

The influence of human leukocyte antigen (HLA) compatibility and lymphocytotoxic crossmatch on acute rejection in living donor liver transplantation (LDLT) has not been well examined. We analyzed 100 consecutive adult LDLT cases. The patient and graft survival rates and post-operative complications were assessed. The relation between the incidence of acute rejection and some clinical factors including HLA and lymphocytotoxic matching was also examined. Patients with HLA DR zero mismatching (p = 0.02) or negative T-lymphocytotoxic crossmatch (p = 0.04) had a significantly lower chance of rejection within 6 wk after LDLT. However the results had no influence on the patient survival. Our results demonstrate that in LDLT, a graft from an HLA-DR zero mismatching or negative T-lymphocytotoxic crossmatch might be advantageous because of the decreased probability of early acute rejection.     

Functional angiotensin II type 2 receptors inhibit growth factor signaling in LNCaP and PC3 prostate cancer cell lines

BACKGROUND: There is clear evidence of a tissue-based renin-angiotensin system in the prostate and studies to date suggest that AT(1)-receptor blocking drugs inhibit the growth of some prostate cancer cell lines and delay the development of prostate cancer. The present studies examine the action of Ang II in two prostate cancer cell lines and report the presence of functional AT(2)-receptors that regulate the actions of growth factors. METHODS: Immunohistochemistry was used to identify the presence of Ang II and QPCR techniques to examine AT(1)- and AT(2)-receptor mRNA expression in androgen-dependent (LNCaP) and independent (PC3) cell lines. The effects of AT(1)- and AT(2)-receptor activation upon EGF-induced DNA synthesis and ERK2 phosphorylation in these cells were also examined. RESULTS: Functional AT(2)-receptors together with Ang II were identified in both cell lines and stimulation of these receptors inhibited EGF-induced DNA synthesis and ERK2 phosphorylation. AT(1)-receptors, although present in both cell lines, were only functional in LNCaP cells where activation stimulated DNA synthesis. CONCLUSIONS: Functional AT(2)-receptors are present and have the capacity to inhibit EGF-induced prostate cancer cell growth in LNCaP and fast growing androgen-independent PC3 cell lines, whereas functional AT(1)-receptors are found only in LNCaP cells where their activation stimulates DNA synthesis.     

Adult Bochdalek hernia with volvulus of the stomach

We report a rare case of Bochdalek hernia, congenital posterolateral diaphragmatic hernia with volvulus of the stomach, in an adult A 74-year-old man was admitted to our hospital complaining of sudden abdominal pain and vomiting. Roentgenologic examination of the chest showed air above the left diaphragm, and the mediastinum was displaced to the right. Upper gastrointestinal series revealed volvulus of the stomach in which the pylorus was displaced to the left. The surgical repair was done through left thoracotomy with combining laparoscopy and thoracoscopy without surgical complications, 1 year later the patient is asymptomatic.     

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.     

Erythropoietin protects the kidneys against ischemia reperfusion injury by activating hypoxia inducible factor-1alpha

BACKGROUND: Ischemia/reperfusion (I/R) injury is closely associated with tissue damage in various organs, as well as in kidney transplants. Erythropoietin (EPO) has been shown to have a cytoprotective effect against hypoxia. We examined the effect of EPO against renal I/R injury and the underlying mechanism. METHODS: Human umbilical vein endothelial cells and human renal proximal tubular epithelial cells were cultured under hypoxic conditions with various EPO concentrations at 37 degrees C and examined the mechanism of cell proliferation by EPO. Moreover, to demonstrate the renoprotective effect in vivo, we treated Sprague-Dawley rats with 100 IU/kg EPO every 2 days for 2 weeks (a total of 6 doses). One day after the last injection, the operations to produce renal I/R injury (bilateral renal occlusion for 60 min) were done, and rats were killed at the end of the reperfusion period (24 hr and 72 hr after reperfusion began). RESULTS: First, we demonstrated in vitro that EPO increased hypoxia inducible factor-1alpha (HIF-1alpha) expression and stimulated proliferation of both cells under hypoxic conditions. Next, we demonstrated in vivo that EPO treatment increased the number of HIF-1alpha-positive cells, and markedly induced the expression of vascular endothelial growth factor messenger RNA. Using pimonidazole, a molecular probe that detects hypoxia, we found that EPO markedly attenuated tubular hypoxia, and reduced the number of terminal transferase dUTP nick end labeling-positive apoptotic cells and alpha-smooth muscle actin-positive interstitial cells. CONCLUSIONS: We suggested a novel HIF-1alpha induction pathway by EPO under hypoxic conditions. Thus, EPO may protect the kidneys against ischemia reperfusion injury by activating HIF-1alpha.