T-type Ca2+ channels and cardiac pacemaker activity

It is well known that T-type Ca(2+) channels differ from L-type Ca(2+) channels on the basis of their low-voltage activation range and rapid inactivation, and therefore can contribute to the pacemaker activity of sinoatrial node cells in the heart. However, proper elucidation of their function on the pacemaker activity has been hampered by the lack of selective pharmacology as well as cell-to-cell difference in the amplitude of T-type Ca(2+) current. In the present study, therefore, we investigated the effects of mibefradil, a selective T-type Ca(2+) channel blocker, on the spontaneous action potential of rabbit sinoatrial node cells. Mibefradil strongly inhibited the spontaneous action potential. In particular, suppression of the slow diastolic depolarization was more marked than that had been expected from a sole inhibition of T-type Ca(2+) channels. T-type Ca(2+) channels may be an important contributor to automaticity in heart cells. Alternatively, mibefradil might have blocked other current system (s) which serves as the main pacemaker current, and thereby inhibited the pacemaker activity.     

Treatment of Orbital Roof Blow-Up Fracture Using a Superior Blepharoplasty Incision

In orbital roof blow-up fractures, reduction can be achieved easily using an approach from the anterior cranial fossa but the procedure is highly invasive. In contrast, an orbital approach using a superior blepharoplasty incision is minimally invasive. However, if bone fragments are adhered to the dura mater, there is a risk of dura mater injury when fragments are moved for reduction. In blow-in fractures, reduction is performed by pushing the bone fragments against the anterior cranial fossa. In contrast, the procedure is difficult for blow-up fractures because bone fragments must be pulled out into the orbit through the anterior cranial fossa. Orbital blow-up fractures are often associated with intracranial injuries and frequently treated by an approach from the anterior cranial fossa. There has not yet been a report that discusses whether reduction of bone fragments should be performed in blow-up fracture without intracranial injury. In this report, we describe two cases of orbital roof blow-up fracture that did not require treatment for intracranial injury and that were treated using an orbital approach. The treatment involved only the release of orbital fat entrapped between bone fragments and did not involve reduction. The treatment outcomes were good in both cases.     

Determinants of ST-segment elevation myocardial infarction as clinical presentation of acute coronary syndrome

Journal of Thrombosis and Thrombolysis - Antiplatelet agents and statin therapies are widely used in patients with known cardiovascular disease. Plaque rupture (PR) and plaque erosion (PE) are the...     

Intracranial hemorrhage in neuro-Behçet's syndrome

OBJECTIVE: Most cerebrovascular disturbances in Beh?et's syndrome are occlusive in nature, while hemorrhage is rare. In this paper, we report three cases of neuro-Beh?et's syndrome presenting with intracerebral hemorrhaging, and discuss the possible causes as they relate to cyclosporine treatment. PATIENTS: Three cases of neuro-Beh?et's syndrome presented with intracranial hemorrhage. One patient had been taking cyclosporine, and the other two patients had never taking cyclosporine. RESULTS: Together with previous reports, these cases suggest that there are two types of intracranial hemorrhage in neuro-Beh?et's syndrome. One type occurs in the center of a lesion and during the acute phase of the disease, while the other occurs in the peripheral lesion and during the subacute phase. CONCLUSIONS: It appears that the intracranial hemorrhages in neuro-Beh?et's syndrome can be divided into two groups. It is possible that the vascular pathologies caused by Beh?et's syndrome and by cyclosporine conspire to induce CNS hemorrhaging in some cases.     

HTLV-I associated interstitial pneumonia--a case report and bronchoalveolar lavage study

A 70-year-old male was admitted to our hospital because of fever and dyspnea. The patient was seropositive for HTLV-I and ATL cells were seen in the peripheral blood in the percentage of 2-5. The proviral DNA was positive and the diagnosis of smoldering ATL was made. His chest X-ray film showed diffuse reticulo-nodular infiltrates in both lung fields. The lung tissue obtained by transbronchial lung biopsy showed the lymphocytic infiltrations in the alveolar septa and the submucosa of the bronchioles. Bronchoalveolar lavage (BAL) fluid showed an increased proportion of lymphocytes that consisted mainly of CD3+ DR+ cells and the CD4+/CD8+ ratio was 2.1 during exacerbation and 0.8 after steroid therapy. Anti-HTLV-I IgG and IgA antibodies were positive in both serum and BAL fluid by Western blotting method. It is suggested that T-lymphocyte alveolitis may occur in patients who are seropositive for HTLV-I and the immunological mechanism seems to be responsible.     

Altered response to inflammatory cytokines in hepatic energy metabolism in inducible nitric oxide synthase knockout mice

BACKGROUND/AIMS: Production of nitric oxide (NO) in the liver is believed to be a critical factor for carbohydrate and energy metabolism in endotoxin shock. The present study focuses on the involvement of NO produced by inducible nitric oxide synthase (iNOS) in glycogen synthesis and energy metabolism stimulated by insulin.METHODS: Primary hepatocytes prepared from wild-type and iNOS knockout (iNOS(-/-)) mice were employed.RESULTS: Incubation of wild-type hepatocytes with a combination of cytokines (interleukin-1beta, tumor necrosis factor-alpha and interferon-gamma) and lipopolysaccharide (cytokines/LPS) inhibited insulin-stimulated glycogen synthesis and adenosine triphosphate (ATP) increase, and decreased the ketone body ratio (KBR) at 8-12 h, concomitant with expression of iNOS protein and NO production. While the glycogen synthesis was suppressed by cytokines/LPS, reduction of the ATP increase and a decrease in KBR by cytokines/LPS were not observed in iNOS(-/-) hepatocytes. Further, N(G)-monomethyl-L-arginine, a NOS inhibitor, reversed the inhibition of ATP increase and decrease in KBR by cytokines/LPS, but not the inhibition of glycogen synthesis. Conversely, addition of S-nitroso-N-acetylpenicillamine, a NO donor, inhibited the insulin-stimulated ATP increase synthesis in iNOS(-/-) hepatocytes, but not the insulin-stimulated glycogen synthesis.CONCLUSIONS: These results demonstrate that NO mediates the suppression of insulin-stimulated energy metabolism, but not glycogen synthesis, in cytokines/LPS-treated hepatocytes.     

Neointimal proliferation around malapposed struts of a sirolimus-eluting stent: optical coherence tomography findings

A 65-year-old man with hypercholesterolaemia and hypertensionunderwent elective percutaneous coronary intervention (PCI)because of exertional angina. Three sirolimus-eluting stents(Cypher; 3.0