Effects of pramipexole on the duration of immobility during the forced swim test in normal and ACTH-treated rats

The dopamine D2/D3 receptor agonist pramipexole has clinically been proven to improve depression or treatment-resistant depression. However, the involvement of the dopamine receptor system on the effect of pramipexole on depression remains unclear. We examined the influence of pramipexole on the duration of immobility during the forced swim test in normal and adrenocorticotropic hormone (ACTH)-treated rats and further analyzed the possible role of dopamine receptors in this effect. Additionally, the mechanism by which pramipexole acts in this model was explored specifically in relation to the site of action through the use of microinjections into the intramedial prefrontal cortex and nucleus accumbens. Pramipexole (0.3–1 mg/kg) significantly decreased the duration of immobility in normal and ACTH-treated rats. This effect was blocked by L-741,626, a D2 receptor antagonist, and nafadotride, a D3 receptor antagonist, in normal rats. Furthermore, infusions of pramipexole into the intranucleus accumbens, but not the medial prefrontal cortex, decreased the immobility of normal and ACTH-treated rats during the forced swim test. Taken together, the results of these experiments suggested that pramipexole, administered into the intranucleus accumbens rather than the medial prefrontal cortex, exerted an antidepressant-like effect on ACTH-treated rats via the dopaminergic system. The immobility-decreasing effect of pramipexole may be mediated by dopamine D2 and D3 receptors.     

Tako-tsubo-like left ventricular dysfunction in a patient with chronic total occlusion of the left anterior descending artery

This report describes a case of tako-tsubo-like left ventricular dysfunction in a patient with chronically occluded left anterior descending artery. A 74-year-od female, experiencing severe pain due to osteoarthritis, presented with chest pain lasting for 6 h. Electrocardiography revealed ST-segment elevation in the anterior and lateral walls. Left ventriculography in the acute phase displayed an akinetic apex and hyperkinetic basal region. Emergent coronary angiography revealed total occlusion of the left anterior descending artery. Although direct coronary angioplasty to the totally occluded left anterior descending artery was unsuccessful, the left ventricular function returned to normal within three weeks after admission. Thallium scintigraphy showed no significant abnormality, and cardiac enzyme elevation showed only a slight increase. In this case, tako-tsubo-like left ventricular dysfunction was considered to occur in the presence of chronically occluded left anterior descending artery.     

Benefit of FOLFOX to unresectable liver metastases secondary from colorectal carcinoma in an oncologic emergency

Liver metastasis is an important prognostic factor in colorectal cancer. The efficacy of resection of metastatic lesions in liver metastasis of colorectal cancer is also widely recognized. However, studies on treatment methods of unresectable cases have not been sufficient and obtaining complete remission (CR) for liver metastasis is rare with chemotherapy. Selection of reliable chemotherapy for unresectable liver metastasis is an urgent necessity. The usefulness of oxaliplatin, 5-flurouracil and leucovorin combination therapy (FOLFOX) has recently been reported, but CR of liver metastasis is rare. The current status and new therapeutic significance of FOLFOX therapy are discussed based on the literature of colorectal cancer chemotherapy to date, and the clinical experience in which we obtained CR for liver metastasis is reported. The patient had stage IV rectal cancer, perforative peritonitis, pelvic abscess and simultaneous multiple liver metastasis. The patient underwent an emergency operation using the Hartmann's procedure. Liver metastasis is considered to be a prognostic factor and FOLFOX was selected as the postoperative chemotherapy, CR of the liver metastasis was obtained. FOLFOX was suggested to have new clinical significance in oncologic emergencies against unresectable liver metastasis in colorectal cancer and should serve as adjuvant chemotherapy that will contribute to improvement of treatment results.     

A new Late Miocene great ape from Kenya and its implications for the origins of African great apes and humans

Extant African great apes and humans are thought to have diverged from each other in the Late Miocene. However, few hominoid fossils are known from Africa during this period. Here we describe a new genus of great ape (Nakalipithecus nakayamai gen. et sp. nov.) recently discovered from the early Late Miocene of Nakali, Kenya. The new genus resembles Ouranopithecus macedoniensis (9.6-8.7 Ma, Greece) in size and some features but retains less specialized characters, such as less inflated cusps and better-developed cingula on cheek teeth, and it was recovered from a slightly older age (9.9-9.8 Ma). Although the affinity of Ouranopithecus to the extant African apes and humans has often been inferred, the former is known only from southeastern Europe. The discovery of N. nakayamai in East Africa, therefore, provides new evidence on the origins of African great apes and humans. N. nakayamai could be close to the last common ancestor of the extant African apes and humans. In addition, the associated primate fauna from Nakali shows that hominoids and other non-cercopithecoid catarrhines retained higher diversity into the early Late Miocene in East Africa than previously recognized.     

DMY gene induces male development in genetically female (XX) medaka fish

Although the sex-determining gene SRY/Sry has been identified in mammals, homologues and genes that have a similar function have yet to be identified in nonmammalian vertebrates. Recently, DMY (the DM-domain gene on the Y chromosome) was cloned from the sex-determining region on the Y chromosome of the teleost fish medaka (Oryzias latipes). DMY has been shown to be required for the normal development of male individuals. In this study, we show that a 117-kb genomic DNA fragment that carries DMY is able to induce testis differentiation and subsequent male development in XX (genetically female) medaka. In addition, overexpression of DMY cDNA under the control of the CMV promoter also caused XX sex reversal. These results demonstrate that DMY is sufficient for male development in medaka and suggest that the functional difference between the X and Y chromosomes in medaka is a single gene. Our data indicate that DMY is an additional sex-determining gene in vertebrates.     

Pediatric pneumonia, pleural effusion, and pericarditis following cat scratch disease and serological cross-reactions among Bartonella henselae and Rickettsia japonica determined by indirect fluorescence antibodies

Cat scratch disease is associated with a variety of systemic manifestations. We report a pediatric case associated with pneumonia, pleural effusion, and pericarditis. A 3-year-old boy developed prolonged fever unresponsive to antibiotic treatment, including azithromycin and minocycline. Although the fever resolved with corticosteroid treatment, Bartonella henselae IgG titer was positive in indirect fluorescence antibodies, as was Rickettsia japonica IgG titer. Both titers were significantly reduced by serum absorption with B. henselae antigens, and we observed a serological cross-reaction between B. henselae and R. japonica.     

Clinical factors predictive of spontaneous remission or relapse in cases of autoimmune pancreatitis

BACKGROUND: The rates of spontaneous remission and relapse of autoimmune pancreatitis (AIP) are not known. OBJECTIVE: To study the clinicopathologic factors predictive of remission and relapse in cases of AIP. DESIGN: Retrospective study. PATIENTS: Of the 20 patients with AIP, complete response to steroid therapy was recognized in 12 patients, and the remaining 8 patients improved without steroid therapy. Seven patients experienced a relapse. RESULTS: Patients who were seronegative for immunoglobulin (Ig) G4, had no obstructive jaundice, no diabetes mellitus, no swelling of the duodenal papilla, negative staining of the duodenal papilla for IgG4, and focal pancreatic swelling showed a greater tendency toward spontaneous remission (P < .05). The results of multivariate analysis revealed that negative staining of the duodenal papilla for IgG4 was the only independent predictor of spontaneous remission of AIP (odds ratio [OR] 1.395, P = .0304). Seropositivity for IgG4, diffuse swelling of the pancreas, and the presence of stricture in the lower part of the bile duct were significantly associated with a relapse of AIP (P < .05) according to the results of univariate analysis, whereas the results of multivariate analysis revealed only diffuse pancreatic swelling as an independent predictor of a relapse of AIP (OR 26.197, P = .0331). CONCLUSIONS: Endoscopic findings are of useful prognostic value, because patients with AIP and with negative staining of the duodenal papilla for IgG4 appeared to have a higher frequency of remission without steroid therapy. Patients with AIP and with diffuse pancreatic swelling were found to be at an increased risk of relapse after the initial steroid administration.     

Inhibition of endogenous Mst1 prevents apoptosis and cardiac dysfunction without affecting cardiac hypertrophy after myocardial infarction

Mammalian sterile 20-like kinase-1 (Mst1) plays an important role in mediating cardiac myocyte apoptosis in response to ischemia/reperfusion. Whether or not Mst1 is also involved in the long-term development of heart failure after myocardial infarction (MI) is unknown. We addressed this issue using transgenic mice with cardiac specific overexpression of dominant negative Mst1 (Tg-DN-Mst1). The left coronary artery was permanently ligated, and the size of MI was similar between Tg-DN-Mst1 and nontransgenic controls (NTg). After 4 weeks, Mst1 was significantly activated in the remodeling area in NTg, but not in Tg-DN-Mst1. Although left ventricular (LV) enlargement was significantly attenuated in Tg-DN-Mst1 compared with NTg, neither LV weight/body weight nor myocyte cross sectional area was statistically different between Tg-DN-Mst1 and NTg. LV ejection fraction was significantly greater in Tg-DN-Mst1 than in NTg (53 versus 38%, P<0.01), whereas LV end-diastolic pressure (6 versus 12 mm Hg, P<0.05) and lung weight/body weight (9.8 versus 12.2 P<0.05) were significantly smaller in Tg-DN-Mst1 than in NTg. The number of TUNEL-positive myocytes (0.17 versus 0.28%, P<0.05) and amount of interstitial fibrosis (5.0 versus 7.1%, P<0.05) in the remodeling area were significantly less in Tg-DN-Mst1 than in NTg. Upregulation of matrix metalloproteinase 2 and proinflammatory cytokines was significantly attenuated in Tg-DN-Mst1. These results indicate that endogenous Mst1 plays an important role in mediating cardiac dilation, apoptosis, fibrosis, and cardiac dysfunction, but not cardiac hypertrophy, after MI. Inhibition of Mst1 improves cardiac function without attenuating cardiac hypertrophy. Thus, Mst1 may be an important target of heart failure treatment.