Ovariectomy Aggravated Sodium Induced Hypertension Associated With Altered Platelet Intracellular Ca in Dahl Rats

Our purpose was to determine the effect of ovariectomy on intracellular Ca²⁺ mobilization and platelet aggregation in sodium induced hypertension. At the age of 12 weeks ovariectomy or sham operation was performed in female Dahl-Iwai salt sensitive rats on a 0.3% NaCl diet. Four weeks later we assessed the effects of ovariectomy and an 8% NaCl diet on agonist induced intracellular Ca²⁺ mobilization in fura-2 loaded platelets and platelet aggregation. Ovariectomy enhanced the increase of systolic blood pressure and heart to body weight ratio on an 8% NaCl diet. However, thrombin evoked intracellular Ca²⁺ was not correlated with systolic blood pressure (r = −0.338, P = .17), and was lowered by sodium loading and ovariectomy (360 ± 23 to 285 ± 9, 296 ± 10 nmol/L, P < .05). Furthermore, the ionomycin induced intracellular calcium fraction in the absence of external Ca²⁺ that reflected internal Ca²⁺ discharge capacity was reduced in ovariectomized rats compared with sham operated rats on an 8% NaCl diet (648 ± 15 v 768 ± 35 nmol/L, P < .05). The internal Ca²⁺ discharge capacity was inversely correlated with systolic blood pressure (r = −0.506, P = .03). In addition to the decreased internal Ca²⁺ discharge capacity, intracellular Ca²⁺-independent platelet aggregation by phorbol 12-myristate 13-acetate, a protein kinase C activator, was significantly enhanced in hypertensive rats. We concluded that ovariectomy enhanced sodium induced hypertension associated with the decreased internal Ca²⁺ discharge capacity and increased platelet aggregation in Dahl-Iwai salt-sensitive rats.     

Degradation of p57Kip2 mediated by SCFSkp2-dependent ubiquitylation

The abundance of the cyclin-dependent kinase (CDK) inhibitor p57Kip2, an important regulator of cell cycle progression, is thought to be controlled by the ubiquitin-proteasome pathway. The Skp1/Cul1/F-box (SCF)-type E3 ubiquitin ligase complex SCFSkp2 has now been shown to be responsible for regulating the cellular level of p57Kip2 by targeting it for ubiquitylation and proteolysis. The elimination of p57Kip2 was impaired in Skp2-/- cells, resulting in abnormal accumulation of the protein. Coimmunoprecipitation analysis also revealed that Skp2 interacts with p57Kip2 in vivo. Overexpression of WT Skp2 promoted degradation of p57Kip2, whereas expression of a dominant negative mutant of Skp2 prolonged the half-life of p57Kip2. Mutation of the threonine residue (Thr-310) of human p57Kip2 that is conserved between the COOH-terminal QT domains of p57Kip2 and p27Kip1 prevented the effect of Skp2 on the stability of p57Kip2, suggesting that phosphorylation at this site is required for SCFSkp2-mediated ubiquitylation. Finally, the purified recombinant SCFSkp2 complex mediated p57Kip2 ubiquitylation in vitro in a manner dependent on the presence of the cyclin E-CDK2 complex. These observations thus demonstrate that the SCFSkp2 complex plays an important role in cell-cycle progression by determining the abundance of p57Kip2 and that of the related CDK inhibitor p27Kip1.     

Disseminated toxoplasmosis after hematopoietic stem cell transplantation showing unusual magnetic resonance images

We herein report a patient who had disseminated toxoplasmosis after hematopoietic stem cell transplantation showing atypical clinical presentation and neuroimaging. Parkinsonism symptoms such as muscle rigidity, bradykinesia, tremor, and postural instability were initial manifestations. Magnetic resonance imaging showed diffuse symmetrical lesions of bilateral basal ganglia lacking ringed enhancement. Post‐mortem analysis revealed multiple tachyzoites of Toxoplasma gondii in the basal ganglia, mid brain, cerebellum, and cardiac muscle.     

Family history of cancer and subsequent risk of cancer: A large-scale population-based prospective study in Japan

Family history (FH) of cancer is an important factor of increased risk of several cancers. Although the association between FH of cancer and concordant cancer risk has been reported in many previous epidemiological studies, no comprehensive prospective study with adjustment for lifestyle habits has evaluated the association of FH of cancer and concordant cancer risk. We investigated the association between FH of cancer and concordant cancer risk in a Japanese population-based prospective study, initiated in 1990 for cohort I and in 1993 for cohort II. We analyzed data on 103,707 eligible subjects without a history of cancer who responded to a self-administered questionnaire including FH of cancer at baseline. Study subjects were followed through 2012 and analyzed using multivariable-adjusted Cox proportional hazards regression models. During 1,802,581 person-years of follow-up, a total of 16,336 newly diagnosed cancers were identified. Any site (Hazard ratios = 1.11 (95% confidence interval = 1.07–1.15]), esophagus (2.11 [1.00–4.45]), stomach (1.36 [1.19–1.55]), liver (1.69 [1.10–2.61]), pancreas (2.63 [1.45–4.79]), lung (1.51 [1.14–2.00]), uterus (1.93 [1.06–3.51]) and bladder cancers (6.06 [2.49–14.74]) with FH of the concordant cancer were associated with an increased risk compared to those without FH. Our findings suggest that having FH of cancer is associated with an increased risk of several concordant cancer incidences in an Asian population. Enquiring about FH of several types of cancer may be important in identifying groups at high-risk of those cancers.     

Tristetraprolin (TTP) gene polymorphisms in patients with rheumatoid arthritis and healthy individuals

Tristetraprolin (TTP) is an intracellular protein that modulates the production of cytokines, including TNFα, by binding to and destabilizing the mRNAs of these cytokines. Therefore, differences in TTP gene expression may affect the severity of inflammatory diseases, such as rheumatoid arthritis (RA). We searched for polymorphisms in the human TTP gene and for this purpose, we sequenced the entire TTP gene in 20 Japanese individuals (ten with RA and ten healthy volunteers) and found one single nucleotide polymorphism (SNP) in the promoter region. We analyzed this SNP (A/G) by restriction fragment length polymorphism method in 155 RA patients and 100 control subjects. While the frequency of A allele in this SNP was similar in RA patients (74.5%) and controls (76.0%), the disease duration in RA patients with genotype GG was shorter than that of patients with genotypes AA/AG and RA patients with genotype GG had a higher probability of being treated with infliximab. We studied the difference in promoter activity between the two alleles by luciferase assay and found that the promoter activity of TTP promoter region with allele A was around two-fold higher than that with allele G. We conclude that this SNP in the promoter region of the TTP gene mildly affects promoter activity, and thus, may influence the disease activity of inflammatory disorders including RA.     

TRIM29 as a novel prostate basal cell marker for diagnosis of prostate cancer

Tripartite motif protein 29 (TRIM29) is one of the TRIM family proteins, some of which function as E3 ubiquitin ligases. In this study, we investigated the usefulness of TRIM29 for diagnosis of prostate cancer. Prostate tissues including carcinoma and non-carcinoma tissues obtained by needle biopsy and radical prostatectomy were used. Immunohistochemistry was performed according to standard procedures using an antibody against TRIM29. Immunohistochemical staining with an antibody against 34βE12, which recognizes cytokeratins 1, 5, 10 and 14, was performed as a control. Basal cells of normal prostatic glands were stained with anti-TRIM29 antibody in all cases, whereas prostate cancer tissues had no or little staining with anti-TRIM29 antibody. TRIM29 is selectively expressed in basal cells of the normal prostate gland, and immunohistochemical staining with anti-TRIM29 antibody showed the same expression pattern as that with 34βE12 in prostate cancer and its benign mimics. Our data indicate that TRIM29 may be useful for distinguishing prostate cancers from benign tissues.     

Efficacy of preoperative portal vein embolization prior to major hepatectomy for patients with impaired liver function: A retrospective study

Hepatocellular carcinoma (HCC) is often associated with chronic liver disease, such as hepatitis or cirrhosis, and this association may limit the use of surgery as a therapy, and if surgery is pursued, may give rise to postoperative hepatic failure. We evaluated the outcome in patients with HCC given preoperative portal vein embolization (PVE) before they underwent major hepatectomy. After PVE, portal pressure increased significantly. Two weeks after PVE, both the volume of the non-embolized lobe and the 15-min indocyamine green retention rate (ICG R15) were significantly increased. The prognostic score, calculated on the basis of age, ICG R15, and the resection rate, was significantly decreased. The operative mortality rate was significantly lower in patients who underwent PVE before surgery than in patients who did not receive PVE. The cumulative survival rate of the PVE patients, even those with cirrhosis of the liver, was significantly higher. Prior PVE appears to allow more extensive major hepatectomy and to lessen the risk of this invasive surgery. However, patients in whom the portal pressure immediately after PVE was more than 30cm H₂O and/or whose prognostic score exceeded 50 points developed postoperative hepatic failure. These features should be kept in mind when it is decided whether surgery is indicated. Nevertheless, preoperative PVE appears to be a beneficial procedure for patients undergoing major hepatectomy, particularly those with chronic liver 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.     

Adenosquamous cell carcinoma arising from the papilla major

A 47-year-old man was admitted to hospital with complaint of general fatigue. Shortly before the admission a suspected obstructive jaundice was diagnosed at a local hospital. On admission, the physical examination was significant for jaundice; total bilirubin was 6.43 mg/dl. The tumor marker CA19-9 was 2056 U/ml. Endoscopic retrograde cholangiopancreatography (ERCP) was performed and showed dilatation of common bile duct and main pancreatic duct, accompanied with an endoscopic naso-biliary drainage (ENBD) in order to reduce the jaundice. The duodenoscopy showed enlarged and deformed papilla. Hypotonic duodenography showed a filling defect at the medial side of the second portion of the duodenum. Ultrasonography (US) showed a hyperechoic lesion, sized 15 mm in diameter, at the pancreas head with dilatation of biliary tract and main pancreatic duct. An abdominal enhanced CT scan showed a mass sized 15 mm at the lower edge of the common bile duct. A selective hepatic arteriography showed no special finding. We performed a pancreatoduodenectomy with dissection of the lymph nodes. The tumor, sized 22x15x20 mm, was white colored and solid on the papilla. Histopathological inspection of the specimen showed an adenosquamous cell carcinoma of the bile duct in the papilla. The tumor was found to infiltrate the neighboring pancreas and to contain metastasis in lymph nodes in the hepatoduodenal ligament, post pancreaticoduodenal and para-aortic lymph nodes. This is the first report on a case of adenosquamous carcinoma of the papilla major.     

Activation of calpain in cultured neurons overexpressing Alzheimer amyloid precursor protein

We have previously reported that overexpression of wild-type amyloid precursor protein (APP) in postmitotic neurons induces cleavage-dependent activation of caspase-3 both in vivo and in vitro. In this study, we investigated the mechanism underlying APP-induced caspase-3 activation using adenovirus-mediated gene transfer into postmitotic neurons derived from human embryonal carcinoma NT2 cells. Overexpression of wild-type APP significantly increased intracellular (45)Ca(2+) content prior to the activation of caspase-3 in NT2-derived neurons. Chelation of intracellular Ca(2+) markedly suppressed APP-induced activation of caspase-3. Furthermore, calpain, a Ca(2+)-dependent cysteine protease, was activated in neurons overexpressing APP as assessed by increased levels of calpain-cleaved alpha-fodrin and autolytic mu-calpain fragments. Neither calpain nor caspase-3 was activated in neurons expressing an APP mutant defective in the Abeta(1-20) domain. Calpain inhibitors almost completely suppressed APP-induced activation of neuronal caspase-3. E64d, a membrane permeable inhibitor of calpain, significantly suppressed APP-induced neuronal death. These results suggest that overexpression of wild-type APP activates calpain that mediates caspase-3 activation in postmitotic neurons.