A multicenter, randomized, double-blind, controlled study to evaluate the efficacy and safety of dantrolene on ventricular arrhythmia as well as mortality and morbidity in patients with chronic heart failure (SHO-IN trial): rationale and design.

BACKGROUND: Leakage of Ca2+ from the sarcoplasmic reticulum (SR) is a critical contributing factor to heart failure pathophysiology. Therefore, reducing SR Ca2+ leaks may provide significant additive benefits when used in combination with conventional therapies. Dantrolene, a drug routinely used to treat malignant hyperthermia, also stabilizes the cardiac isoform of the release channel (RyR2), thus decreasing SR Ca2+ leaks. The purpose of this study is to evaluate the effect of chronic administration of dantrolene on heart failure and lethal arrhythmia in patients with chronic heart failure and reduced ejection fraction in a multicenter, randomized, double-blind, controlled study. METHODS: Patients with chronic heart failure who had functional status of New York Heart Association class II and III and a left ventricular ejection fraction <40% were treated according to the Japanese Circulation Society, the European Society of Cardiology, and the American Heart Association/the American College of Cardiology guidelines for diagnosis and treatment of acute and chronic heart failure. Patients were randomized and divided into two groups in a double-blind fashion: dantrolene group and placebo group (target sample size: 300 cases). These drugs were administered for 96 weeks. The primary endpoint is cardiovascular death, first hospitalization for exacerbation of heart failure, or lethal arrhythmia [ventricular tachycardia (VT) storm, sustained VT, ventricular fibrillation] for 2 years after starting administration of dantrolene 1 cap (25mg) three times daily (if not tolerable, two times daily) or matching placebo. RESULTS: This paper presents the rationale and trial design of the study. Recruitment for the study started on 8 December 2017. CONCLUSIONS: The results of this trial will clarify the efficacy and safety of dantrolene for ventricular arrhythmia, as well as mortality and morbidity in patients with chronic heart failure and reduced ejection fraction during guideline-directed medical treatment.

Effects of local infiltration analgesia for posterior knee pain after total knee arthroplasty: comparison with sciatic nerve block.

BACKGROUND: Although femoral nerve block provides good analgesia after total knee arthroplasty (TKA), residual posterior knee pain may decrease patient satisfaction. We compared the efficacy of periarticular infiltration analgesia (PIA) and sciatic nerve block (SNB) for posterior knee pain. METHODS: Forty-nine patients scheduled for TKA were prospectively randomized into the PIA group (n = 25) or SNB group (n = 24) and received general anesthesia with ultrasound-guided femoral nerve block (FNB). In the PIA group, 60 ml 0.5% ropivacaine and 0.3 mg epinephrine were injected intraoperatively into the periarticular soft tissue before inserting the components. In the SNB group, patients received ultrasound-guided SNB with 20 ml 0.375% ropivacaine and periarticular infiltration with 20 ml normal saline and 0.3 mg epinephrine. We evaluated postoperative pain scores, posterior knee pain, frequency of rescue analgesics for 36 h, and performance time of PIA and SNB. RESULTS: Visual analogue pain scores at 12-24 h were significantly lower in the PIA group than in the SNB group (p < 0.05). The majority of patients had no posterior knee pain. There were no significant differences between the groups in frequency and time of first administration of rescue analgesics and in side effects. Time for performance of periarticular infiltration was significantly shorter than that for SNB (p < 0.05). The dose of intraoperative remifentanil was significantly lower in the SNB group than in the PIA group (p < 0.001). CONCLUSIONS: The combination of FNB and PIA provides sufficient analgesia after TKA. The rapid and convenient periarticular infiltration technique could be a good alternative to SNB.

Microendoscopy-assisted muscle-preserving interlaminar decompression for lumbar spinal stenosis: clinical results of consecutive 105 cases with more than 3-year follow-up.

STUDY DESIGN: A retrospective review of data collected prospectively on patients who underwent microendoscopy-assisted muscle-preserving interlaminar decompression (MILD) for lumbar spinal stenosis. OBJECTIVE: To evaluate the clinical results including surgical invasiveness and reduction rate of facet joint with a follow-up of more than 3 years. SUMMARY OF BACKGROUND DATA: Hatta et al reported microscopic posterior decompression procedure, MILD for lumbar spinal stenosis with reference to the cervical central approach put forth by Shiraishi. Mikami et al applied spinal microendoscopy to MILD procedure (microendoscopy-assisted MILD). METHODS: One hundred five consecutive patients, who underwent microendoscopy-assisted MILD, participated in this study. Operative time, blood loss, visual analogue scale (VAS), serum creatine kinase and C-reactive protein, surgical complications, reduction rate of the facet joint, Japanese Orthopaedic Association score, and Short-Form 36 were evaluated. RESULTS: The operative time was 99.3 minutes and the intraoperative bleeding was 15.7 mL on average. The mean VAS score to assess surgical site pain was 20.6 mm on postoperative day 1. The mean serum creatine kinase on postoperative day 1 and C-reactive protein on postoperative day 3 were 145.4 IU/L and 2.7 mg/dL, respectively. Surgical complications were identified in 2 cases, cauda equina injury and dural tear. The mean reduction rate of the facet joint was 3%. The follow-up rate was 83.3% and the mean follow-up period was 52.7 months. The Japanese Orthopaedic Association score improved significantly from 14.8 to 23.7 points on average. Significant improvements in Short-Form 36 were observed in all subscales except in General Health. Revision surgical procedures were performed in 8 cases at the operated level including 4 of juxtafacet cyst, 3 of disc herniation, and 1 of insufficient decompression. CONCLUSION: Microendoscopy-assisted MILD is a minimally invasive procedure and favorable clinical results can be expected for lumbar spinal stenosis. LEVEL OF EVIDENCE: 4.

Nipple adenoma arising from axillary accessory breast: a case report.

Nipple adenoma is a relatively rare benign breast neoplasm, and cases of the disease arising from the axillary accessory breast have very seldom been reported in the English literature. We report a case of nipple adenoma arising from axillary accessory breast including clinical and pathological findings. An 82-year-old woman presented with the complaint of a small painful mass in the right axilla. Physical examination confirmed a well-defined eczematous crusted mass that was 8 mm in size. The diagnosis of nipple adenoma was made from an excisional specimen on the basis of characteristic histological findings. Microscopic structural features included a compact proliferation of small tubules lined by epithelial and myoepithelial cells, and the merging of glandular epithelial cells of the adenoma into squamous epithelial cells in the superficial epidermal layer. Because clinically nipple adenoma may resemble Paget's disease and pathologically can be misinterpreted as tubular carcinoma, the correct identification of nipple adenoma is an important factor in the differential diagnosis for axillary tumor neoplasms. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1186821489769063.

A case of gallstone ileus displaying spontaneous closure of cholecystoduodenal fistula after enterolithotomy.

INTRODUCTION: Gallstone ileus, a rare complication of cholelithiasis and cholecystitis, is a relatively rare cause of alimentary tract obstruction. It is usually associated with a cholecystoenteric fistula through which a gallstone has passed into the gastrointestinal tract. Cholecystoenteric fistula uncommonly closes spontaneously, the period between formation and closure having rarely been reported. In addition, endoscopic detection of cholecystoenteric fistulous closure has seldom been reported. PRESENTATION OF CASE: We report a 51-year-old Japanese man with gallstone ileus in whom spontaneous closure of a cholecystoduodenal fistula was observed by endoscopy 2 weeks after laparoscopy-assisted enterolithotomy. DISCUSSION: Laparoscopy-assisted enterolithotomy for gallstone ileus allows direct diagnosis of gallstone ileus and assessment of the status of adhesions affecting the biliary tract. CONCLUSION: Endoscopic confirmation of fistulous closure after laparoscopy-assisted enterolithotomy is a minimally invasive approach that may avert the need for biliary surgery.

Tongue muscle-derived stem cells express connexin 43 and improve cardiac remodeling and survival after myocardial infarction in mice.

BACKGROUND: Cell transplantation therapy for heart failure is hindered by poor differentiation into cardiomyocytes and arrhythmias caused by the poor expression of connexin 43 (Cx43). A new stem cell source for cardiac regeneration is needed. METHODS AND RESULTS: Tongue muscle-derived Sca-1(+) cells (TDSCs) were isolated from normal and green fluorescence protein (GFP)-transgenic mouse tongues using surface antigen Sca-1. Cardiomyogenic differentiation was confirmed by measuring the calcium transient and the expression of cardiac-specific genes. The formation of gap junctions was confirmed by the expression of Cx43 and the dye transfer method. The contraction of regenerated cells was demonstrated by the calcium transients. GFP mouse-derived TDSCs were transplanted into hearts in a model of acute myocardial infarction. Three months after transplantation, LV remodeling was attenuated and the survival rate was improved compared with the control group. CONCLUSIONS: TDSCs form gap junctions and improve cardiac function and long-term survival after myocardial infarction.

Pleiotropic effects of the beta-adrenoceptor blocker carvedilol on calcium regulation during oxidative stress-induced apoptosis in cardiomyocytes.

Carvedilol is a nonselective beta-adrenoceptor blocker with multiple pleiotropic actions. A recent clinical study suggested that carvedilol may be superior to other beta-adrenoceptor blockers in the treatment of heart failure. Despite numerous investigations, the underlying mechanisms of carvedilol on improving heart failure are yet to be fully established. The purpose of this study is to clarify the pleiotropic effect of carvedilol on cytosolic and mitochondrial calcium regulation during oxidative stress-induced apoptosis in cardiomyocytes. Carvedilol (10 microM), but not metoprolol (10 microM), reduced H2O2 (100 microM)-induced apoptosis in neonatal rat cardiomyocytes. During the process, changes in cytosolic calcium concentration ([Ca2+]i) and mitochondrial calcium concentration ([Ca2+]m) and mitochondrial membrane potential (DeltaPsim) were measured by fluorescent probes [Fluo-3/acetoxymethyl ester (AM), Rhod-2/AM, and tetramethylrhodamine ethyl ester, respectively] and imaged by laser confocal microscopy. The results showed that H2O2 caused [Ca2]m overload first, followed by [Ca2+]i overload, leading to DeltaPsim dissipation and the induction of apoptosis. Carvedilol (10 microM) significantly delayed these processes and reduced apoptosis. These effects were not observed with other beta-adrenoceptor blockers (metoprolol, atenolol, and propranolol) or with a combination of the alpha (phentolamine)- and the beta-adrenoceptor blocker. The antioxidant N-acetyl-L-cysteine (NAC, 5 mM) and the combination of NAC and propranolol (10 microM) showed an effect similar to that of carvedilol. Therefore, the effect of carvedilol on H2O2-induced changes in [Ca2+]m, [Ca2+]i, and DeltaPsi(m) is independent of alpha- and beta-adrenoceptors but is probably dependent on the antioxidant effect.

Carvedilol inhibits mitochondrial oxygen consumption and superoxide production during calcium overload in isolated heart mitochondria.

BACKGROUND: The COMET study suggested the better effect of carvedilol to metoprolol in treating heart failure. However, its underlying mechanisms of action remain unclear. As a result, evaluation of the distinct effects of both drugs on the mitochondrial function and reactive oxygen species (ROS) production during Ca(2+) overload was investigated. METHODS AND RESULTS: The mitochondrial oxygen consumption (mVO(2)) and the mitochondrial ROS production in isolated rat heart mitochondria was measured. Ca(2+) overload from 10 to 100 micromol/L augmented mVO(2) was from 527+/-139 to 671 +/-138 nmol/mg (p<0.05), and this was then completely suppressed by carvedilol (1 micromol/L), but not by metoprolol (100 micromol/L). Ca(2+) overload augmented the ROS production upon complex I injury (9.7+/-1.2 to 11.4+/-1.4 nmol/mg, p<0.05). Carvedilol dose-dependently suppressed this ROS production, whereas metoprolol did not. CONCLUSIONS: Carvedilol, but not metoprolol, was thus found to inhibit the calcium-dependent augmentation of mVO(2) and ROS production upon complex I injury. This new effect of carvedilol might partly explain the beneficial effect of carvedilol for the treatment of heart failure.

NO donor-activated PKC-delta plays a pivotal role in ischemic myocardial protection through accelerated opening of mitochondrial K-ATP channels.

Nitric oxide (NO) can activate protein kinase C (PKC) and the activation of mitochondrial ATP-sensitive potassium (K-ATP) channels is cardioprotective. However, interactions among NO, PKC, and mitochondrial K-ATP channels remain vague. To clarify the cardioprotective mechanism induced by nicorandil, we compared its ability to activate PKC isoforms with that of the mitochondrial K-ATP channel opener, diazoxide. We induced myocardial infarction in rats by 30 minutes of ischemia followed by reperfusion, then assessed the infarct size 3 weeks later. We also examined the translocation of PKC isoforms in the isolated perfused rat heart. Nicorandil and diazoxide reduced infarct size, and the effect of nicorandil, but not of diazoxide attenuated by the PKC inhibitor, chelerythrine, or by the NO quencher, carboxy PTIO. Immunoblotting revealed that nicorandil translocated PKC-delta to the mitochondria, and that this was inhibited by carboxy PTIO. The protective effect of nicorandil against myocardial infarction partly depended on the translocation of PKC-delta to the mitochondria, which we attributed to the NO donor effect of nicorandil. The PKC-delta- dependent activation of mitochondrial K-ATP channel opening might be synergistic with its direct effect, making nicorandil an efficient opener of such channels.

A family of hypokalemic periodic paralysis with CACNA1S gene mutation showing incomplete penetrance in women.

Familial hypokalemic periodic paralysis is an autosomal dominant genetic muscle disease characterized by periodic attacks of muscle weakness associated with a decrease in serum potassium. There are two major missense mutation sites in the calcium channel alpha1 subunit (CACNA1S) gene in these patients. We recently encountered a 13-year-old Japanese boy who had collapsed following exercise and was found to have a low serum potassium level. Clinical and genetic studies including exploration of his family tree proved that he and his maternal relatives had the disease with the missense mutation, Arg528His (CGC --> CAC). However, his mother and grandmother had no symptoms of the disease, indicating reduced penetrance in female carriers. Sexual difference in the penetrance of this disease and the association between the clinical symptoms and the types of genetic defects are discussed.

Initiation and transduction of stretch-induced RhoA and Rac1 activation through caveolae: cytoskeletal regulation of ERK translocation.

The Rho family small GTPases play a crucial role in mediating cellular responses to stretch. However, it remains unclear how force is transduced to Rho signaling pathways. We investigated the effect of stretch on the activation and caveolar localization of RhoA and Rac1 in neonatal rat cardiomyocytes. In unstretched cardiomyocytes, RhoA and Rac1 were detected in both caveolar and non-caveolar fractions as assessed using detergent-free floatation analysis. Stretching myocytes for 4 min activated RhoA and Rac1. By 15 min of stretch, RhoA and Rac1 had dissociated from caveolae, and there was decreased coprecipitation of RhoA and Rac1 with caveolin-3. To determine whether compartmentation of RhoA and Rac1 within caveolae was necessary for stretch signaling, we disrupted caveolae with methyl beta-cyclodextrin (MbetaCD). Treatment with 5 mm MbetaCD for 1 h dissociated both RhoA and Rac1 from caveolae. Under this condition, stretch failed to activate RhoA or Rac1. Stretch-induced actin cytoskeletal organization was concomitantly impaired. Interestingly the ability of stretch to activate extracellular signal-regulated kinase (ERK) was unaffected by MbetaCD treatment, but ERK translocation to the nucleus was impaired. Stretch-induced hypertrophy was also inhibited. Actin cytoskeletal disruption with cytochalasin-D also prevented stretch from increasing nuclear ERK, whereas actin polymerization with jasplakinolide restored nuclear translocation of activated ERK in the presence of MbetaCD. We suggest that activation of RhoA or Rac1, localized in a caveolar compartment, is essential for sensing externally applied force and transducing this signal to the actin cytoskeleton and ERK translocation.

Characterization of lpa(2) (Edg4) and lpa(1)/lpa(2) (Edg2/Edg4) lysophosphatidic acid receptor knockout mice: signaling deficits without obvious phenotypic abnormality attributable to lpa(2).

Lysophosphatidic acid (LPA), a bioactive lipid produced by several cell types including postmitotic neurons and activated platelets, is thought to be involved in various biological processes, including brain development. Three cognate G protein-coupled receptors encoded by lpa(1)/lp(A1)/Edg-2/Gpcr26, lpa(2)/lp(A2)/Edg-4, and lpa(3)/lp(A3)/Edg-7 mediate the cellular effects of LPA. We have previously shown that deletion of lpa(1) in mice results in craniofacial dysmorphism, semilethality due to defective suckling behavior, and generation of a small fraction of pups with frontal hematoma. To further investigate the role of these receptors and LPA signaling in the organism, we deleted lpa(2) in mice. Homozygous knockout (lpa(2)((-/-))) mice were born at the expected frequency and displayed no obvious phenotypic abnormalities. Intercrosses allowed generation of lpa(1)((-/-)) lpa(2)((-/-)) double knockout mice, which displayed no additional phenotypic abnormalities relative to lpa(1)((-/-)) mice except for an increased incidence of perinatal frontal hematoma. Histological analyses of lpa(1)((-/-)) lpa(2)((-/-)) embryonic cerebral cortices did not reveal obvious differences in the proliferating cell population. However, many LPA-induced responses, including phospholipase C activation, Ca(2+) mobilization, adenylyl cyclase activation, proliferation, JNK activation, Akt activation, and stress fiber formation, were absent or severely reduced in embryonic fibroblasts derived from lpa(1)((-/-)) lpa(2)((-/-)) mice. Except for adenylyl cyclase activation [which was nearly abolished in lpa(1)((-/-)) fibroblasts], these responses were only partially affected in lpa(1)((-/-)) and lpa(2)((-/-)) fibroblasts. Thus, although LPA(2) is not essential for normal mouse development, it does act redundantly with LPA(1) to mediate most LPA responses in fibroblasts.

A case of TSH receptor antibody-positive hyperthyroidism with functioning metastases of thyroid carcinoma.

The presence of TSH receptor antibody (TRAb) is rarely responsible for hyperthyroidism due to metastatic lesions of thyroid carcinoma. A 70-year-old woman was incidentally found to be thyrotoxic around the time that external irradiation was performed for multiple bone metastases 9 years after subtotal thyroidectomy for follicular carcinoma. Hyperthyroidism persisted after oral administration of thiamazole. Relevant laboratory data were as follows: FT4 9.6 ng/L, FT3 7.3 ng/L, TSH <0.19 mU/L, TBII 70, TSAb 735, and Tg 32,000 microg/L. 131I-total body scan showed 131I accumulation in the occipital bone, cervical vertebra, thoracic vertebra, ilium, and residual thyroid gland. Since the ilium uptake (11.6) was markedly higher compared to the residual thyroid gland uptake (0.14), four subsequent 131I therapies were performed. The patient became hypothyroid, and TBII became negative. TSAb became negative after the first 131I-therapy but has increased again to 204 at present. Tg was 1,962 microg/L despite high TSH levels. 131I accumulation in the residual thyroid, cervical vertebra, and thoracic vertebra disappeared. Also 131I accumulation in the ilium has gradually decreased, but the image in the occipital bone has become markedly distinctive. This is a rare case characterized by TRAb-positive hyperthyroidism, by T3-predominant thyrotoxicosis, and by stronger accumulation of 131I in the metastatic tumor than in the residual thyroid gland. Thus, the response to TRAb and 131I-therapy is different among metastatic thyroid tissues.

Marked perinatal lethality and cellular signaling deficits in mice null for the two sphingosine 1-phosphate (S1P) receptors, S1P(2)/LP(B2)/EDG-5 and S1P(3)/LP(B3)/EDG-3.

Five cognate G protein-coupled receptors (S1P(1-5)) have been shown to mediate various cellular effects of sphingosine 1-phosphate (S1P). Here we report the generation of mice null for S1P(2) and for both S1P(2) and S1P(3). S1P(2)-null mice were viable and fertile and developed normally. The litter sizes from S1P(2)S1P(3) double-null crosses were remarkably reduced compared with controls, and double-null pups often did not survive through infancy, although double-null survivors lacked any obvious phenotype. Mouse embryonic fibroblasts (MEFs) were examined for the effects of receptor deletions on S1P signaling pathways. Wild-type MEFs were responsive to S1P in activation of Rho and phospholipase C (PLC), intracellular calcium mobilization, and inhibition of forskolin-activated adenylyl cyclase. S1P(2)-null MEFs showed a significant decrease in Rho activation, but no effect on PLC activation, calcium mobilization, or adenylyl cyclase inhibition. Double-null MEFs displayed a complete loss of Rho activation and a significant decrease in PLC activation and calcium mobilization, with no effect on adenylyl cyclase inhibition. These data extend our previous findings on S1P(3)-null mice and indicate preferential coupling of the S1P(2) and S1P(3) receptors to Rho and PLC/Ca(2+) pathways, respectively. Although either receptor subtype supports embryonic development, deletion of both produces marked perinatal lethality, demonstrating an essential role for combined S1P signaling by these receptors.

Effect of ischemic preconditioning and mitochondrial KATP channel openers on chronic left ventricular remodeling in the ischemic-reperfused rat heart.

The influence of ischemic preconditioning (IP) and mitochondrial ATP-sensitive potassium (mito-KATP) channel openers on chronic left ventricular (LV) remodeling remains unknown, so the effect of IP and mito-KATP channel openers on the LV pressure-volume curve was assessed in rats subjected to 30 min ischemia followed by a 3-week reperfusion. Infarct size was histologically determined at 3 weeks after reperfusion. The LV pressure-volume curve was significantly shifted left by IP, diazoxide and nicorandil compared with the controls. These effects were blocked by the selective mito-KATP channel blocker 5-hydroxydecanoate. The LV remodeling and the infarct size at 3 weeks after reperfusion correlated well, indicating that the reduction of LV remodeling in the ischemic-reperfused model was strongly influenced by attenuation of the ischemic injury. LV remodeling in the chronic phase is attenuated by IP and mito-KATP channel openers with concomitant reduction of infarct size.