Undiagnosed Cardiac Sarcoidosis Causing Refractory Heart Failure After Acute Myocardial Infarction due to Thromboembolism

A 61-year-old woman suffered chest pain and was admitted to a nearby hospital emergency department. She was diagnosed with acute myocardial infarction probably due to thromboembolism in the left anterior descending coronary artery and aspiration thrombectomy was performed. Afterwards, she developed refractory heart failure with severe global left ventricular dysfunction and was transferred to our hospital. An ¹⁸F-FDG-PET/CT scan revealed abnormal ¹⁸F-FDG uptake in non-infarcted regions of the left ventricle. Non-caseating granulomas were detected by biopsy from a skin eruption. She was diagnosed with cardiac sarcoidosis. In cases of refractory heart failure which cannot be explained only by myocardial infarction, evaluation of other undiagnosed cardiomyopathies is important for optimal management.

A comparison of rate control and rhythm control in tachycardia induced cardiomyopathy patients with persistent atrial flutter

Background/Introduction

Tachycardia induced cardiomyopathy (TIC) is a potentially reversible dysfunction of the left ventricle (LV) caused by tachyarrhythmias. Early recognition of TIC and treatment of the culprit arrhythmia using pharmacological therapy or catheter ablation results in the recovery of LV function. For atrial flutter (AFL)-induced TIC, rhythm control strategy, such as catheter ablation has been recommended. On the other hand, the efficacy of rate control strategy has remained unclear due to the difficulty of control with arrhythmic medications. However, not all patients can take rhythm control treatments due to their backgrounds.

Purpose

The aim of this cohort study was to establish whether rate control strategy using β-blocker is as effective as invasive rhythm control strategy for the recovery of LV function in patients with TIC due to AFL.

Methods

We prospectively assessed 47 symptomatic non-ischaemic heart failure (HF) patients with left ventricular ejection fraction (LVEF) below 50% and suspected TIC induced by persistent AFL. Patients were divided into rhythm control strategy group (n=22, treatment: catheter ablation, electrical cardioversion) and rate control strategy group (n=25, treatment: bisoprolol). As a sub-group study, the rate control strategy group was divided into the strict rate control group (n=12, average heart rate below 80 bpm) and lenient rate control group (n=13, average heart rate below 110 bpm). The primary outcome was the recovery of LV function, defined as an increase of LVEF over 20% or to a value of 55% or greater after 6 months.

Results

There were no significant differences in baseline AFL heart rate, New York Heart Association class, LVEF, estimated glomerular filtration rate, and brain natriuretic peptide between the two groups. A greater proportion of patients who showed the recovery of LVEF after 6 months belonged to the rhythm control strategy group (90.9% vs. 52.0%, p=0.004). The cumulative incidence of HF re-hospitalization was significantly higher in the rate control strategy group than in the rhythm control strategy group (hazard ratio: 4.90, 95% CI: 1.06–22.69). As a result of sub-group study, LVEF recovery was greater in the strict rate control group compared to the lenient rate control group (75.0% vs. 30.8%, p=0.027)

Conclusion

Rate control strategy was significantly inferior to rhythm control strategy for the recovery of LVEF in TIC patients with persistent AFL. Rhythm control should be the first choice in the management of TIC with AFL, and strict rate control should be an alternative if rhythm control is not available.

Primary outcomes

Funding Acknowledgement

Type of funding source: None

AB0904 PERSISTENCE AND REASONS FOR DISCONTINUATION OF DENOSUMAB IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Denosumab, a fully human monoclonal antibody to receptor activator of nuclear factor kappa B ligand, which inhibits osteoclast differentiation, activation and survival, not only increases bone mineral density but also inhibits the progression of bone erosion in patients with rheumatoid arthritis (RA)1-3). Therefore, denosumab have been preferably prescribed for patients with RA recently. The persistence with denosumab, which is administered subcutaneously once every 6 months, was reported higher than with oral bisphosphonates4), and in the prospective cohort studies, the persistence rate for one year was reported to be 82-95%5-6). However, there have been no report about the persistence in patients with RA treated with denosumab, moreover the reasons for discontinuation of denosumab.

Objectives:

The aims of this single center retrospective cohort study were 1) to assess the persistence with denosumab in a routine clinical setting and 2) to identify the reasons of discontinuation in patients with RA. And we also reviewed the clinical outcomes of osteonecrosis of the jaw in patients with RA during denosumab treatment.

Methods:

The present study is based on databases from our hospital, which include age, gender, date of injection of denosumab, as well as information on patients’ characteristics. Patients were included in this study when denosumab were newly started at our department during the period from June 1, 2013 and September 30, 2017. In this study, persistence was defined as patients with an interval between injections of no longer than 6 months plus 8 weeks. Patients were followed until censoring (death, transferring to another hospital) or the end of the study (August 3, 2018).

We investigated reasons for the discontinuation of denosumab. Major reasons for the discontinuation of denosumab were classified as adverse event, anxiety over adverse events, patient’s transfer or request, doctor’s careless lack of refilling an injection, and other reason.

We identified patients who had been diagnosed as osteonecrosis of the jaw, and demographic, pharmacological, and clinical data were collected from medical records.

Results:

One hundred and seventy-five patients were identified. Kaplan–Meier analysis showed a slow decline of persistence after initiating denosumab therapy, dropping to 80.4 and 61.9 % after 1 and 2 years of follow-up. When analyzing the reason of discontinuation as adverse events, the persistence rate of denosumab was at 89.4, and 79.4% at 1, and 2 years of follow-up, respectively.

During 2-year period, 72 patients discontinued denosumab. A total of 27 adverse events occurred, of which five events were osteonecrosis of the jaw. The other reasons for adverse event included death in four, fracture in three, and so on. Six patients discontinued due to anxiety over dental adverse event. Thirteen patients were in doctor’s careless lack of refilling an injection

All five patients who were diagnosed as osteonecrosis of the jaw had received the treatment with prednisolone, and four were treated with biologic drugs. All patients stopped denosumab and switched to other drugs including teriparatide. All patients underwent surgical curettages of necrotic bone and cured.

Conclusion:

Persistence of denosumab in patients with RA is comparable to that in postmenopausal women with osteoporosis. Dental screening and care should be important to continue denosumab treatment.

References:

[1]Cohen SB.Arthritis Rheum. 2008;58:1299–1309.

[2]Takeuchi T.Ann Rheum Dis. 2019;78:899–907.

[3]Ebina K.Osteoporos Int. 2018;29:1627–1636.

[4]Hadji P.Osteoporos Int. 2016;27:2967–2978.

[5]Silverman SL.Arch Osteoporos. 2018;13:85. doi:10.1007/s11657-018-0491-z

[6]Hadji P.Osteoporos Int. 2015;26:2479–2489.

Disclosure of Interests:

Shinichi Mizuki Speakers bureau: AbbVie, Asahi Kasei, Chugai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Tatsuya Kai: None declared, Koji Mishima: None declared, Hiroko Ikeuchi: None declared, Kensuke Oryoji: None declared

Performance verification of a precise vibrating-wire magnet alignment technique for next-generation light sources

The high-accuracy alignment of magnets is a key issue in the development of next-generation light-source rings. To obtain adequate dynamic apertures, the magnets must be aligned to an accuracy of 10 µm or better. Recently, a new technique that utilizes a vibrating wire has attracted attention for this purpose as it can directly determine with high resolution the magnetic centers in a series of multipole magnets on a straight section between bending magnets. In conventional vibrating-wire alignment techniques, wire sag, which causes alignment errors, is determined from the theoretical catenary curve. By contrast, in the present study, we have measured the sag profiles of various wires in the longitudinal direction to micrometer-order accuracy. We concluded that we can reduce deviations of the actual wire sag from the theoretical curve by choosing a suitable wire. By setting up a test bench of a vibrating-wire alignment system for a series of multipole magnet on a straight section, we have achieved the total error of the magnetic-center measurements of micrometer-order in the standard deviation. Moreover, two systematic error factors, the drift of the magnetic centers due to thermal deformations of the magnets after they are excited and the change in the magnetic centers due to reassembly of the magnets after installing the vacuum chamber, are included in practical magnet alignments. We have experimentally investigated these error factors using the test bench.

Preparation of protic ionic liquids containing cyclic oligosiloxane frameworks

Protic ionic liquids containing cyclic oligosiloxane frameworks, which were prepared by the hydrolytic condensation method, exhibited relatively high thermal stabilities.

Polyethylenimine combined with liposomes and with decreased numbers of primary amine residues strongly enhanced therapeutic antiviral efficiency against herpes simplex virus type 2 in a mouse model

The development of antiviral agents that have novel mechanisms of action is urgently required in the topical therapy of herpes simplex virus type 2 (HSV-2) infections. We reported previously that topical application of branched 3610-Da polyethylenimine (PEI) exhibited preventative antiviral activity. In this study, to develop therapeutic anti-HSV-2 agents, the most potent PEI combined with ~200 nm-sized liposomes with or without oleic acid (liposomes/PEI) was selected in vitro and further evaluated using in vivo studies. The mechanism of action in vivo was elucidated using PEIs with decreased numbers of primary amine residues, resulting from ethylene carbonate treatment, and polyallylamine, a linear polyamine consisting of primary amines. Cytotoxicity and antiviral activity in vitro, and the appearance of acute herpetic disease and virus yields in mice intravaginally administered with liposomes/PEI were evaluated in cell culture assays and a mouse genital herpes model, respectively. In addition, the cellular association of liposome/PEI was examined by flow cytometry and confocal microscopy. PEI showed higher antiviral activity postinfection than preinfection in vivo. Liposome/PEI and PEI with decreased numbers of primary amine residues at a dose of 0.2 mg PEI/mouse exhibited more potent therapeutic antiviral activity than acyclovir and PEI alone without acute lesion appearance or toxicity pre- or postinfection, but polyallylamine was moderately effective only preinfection. Liposome concentrations were important for the effectiveness of liposome/PEI. This finding suggests that PEI combined with liposomes and with slightly decreased numbers of primary amines may be an effective vaginally administrated antiviral drug, and secondary and tertiary amine residues of PEI may contribute to the inhibitory efficiency against viral infection.

X-ray polarization spectroscopy to study anisotropic velocity distribution of hot electrons produced by an ultra-high-intensity laser

The anisotropy of the hot-electron velocity distribution in ultra-high-intensity laser produced plasma was studied with x-ray polarization spectroscopy using multilayer planar targets including x-ray emission tracer in the middle layer. This measurement serves as a diagnostic for hot-electron transport from the laser-plasma interaction region to the overdense region where drastic changes in the isotropy of the electron velocity distribution are observed. These polarization degrees are consistent with analysis of a three-dimensional polarization spectroscopy model coupled with particle-in-cell simulations. Electron velocity distribution in the underdense region is affected by the electric field of the laser and that in the overdense region becomes wider with increase in the tracer depth. A full-angular spread in the overdense region of 22.4 degrees -2.4+5.4 was obtained from the measured polarization degree.

The effect of Lactobacillus helveticus fermented milk on sleep and health perception in elderly subjects

OBJECTIVE

To study the effect of Lactobacillus helveticus fermented milk on sleep and health perception in elderly healthy subjects.

SUBJECTS

The study included 29 healthy elderly subjects aged 60-81 years.

METHODS

Prospective, randomized, double-blind and placebo-controlled, with a crossover design. The study included two intervention periods of 3 weeks each, separated by a 3-week washout period. Subjects took 100 g of fermented milk drink or a placebo drink (artificially acidified milk) daily in the first supplementary period and the other drink in the second supplementary period. For each period, we measured sleep quality by means of actigraphy and a sleep questionnaire, and assessed the quality of life (QOL) by SF-36 health survey.

RESULTS

There was a significant improvement in sleep efficiency (P=0.03) and number of wakening episodes (P=0.007) in actigraph data after intake of fermented milk, whereas no significant changes were observed for the placebo. Fermented milk did not improve the SF-36 scores significantly from the baseline period. In the GH domain (general health perception) of the SF-36, however, there was marginal improvement as compared to the baseline period. Although the difference between fermented milk and placebo was not statistically significant for any of the sleep or QOL parameters, fermented milk produced slightly greater mean values for many parameters.

CONCLUSION

This short-term (3-week) intervention study indicates that Lactobacillus helveticus fermented milk may have a more favorable effect on improving sleep in healthy elderly people as compared with placebo.

A phase II study of doxorubicin plus paclitaxel followed by weekly paclitaxel as neoadjuvant chemotherapy for breast cancer (SBCCSG-07)

11103

Background: The primary aim of this study was to estimate the rate of clinical and pathologic response to preoperative doxorubicin and paclitaxel followed by weekly paclitaxel in stage II /III breast cancer. Secondary objective included the determination of time to progression, over all survival, the rate of breast conservation surgery, feasibility and safty. Saitama breast cancer clinical study group-07 study (SBCCSG-07; CTR:UMIN000000504) Methods: Patients were treated with 50 mg/m2 of doxorubicin intravenously and 150 mg/m2 of paclitaxel both administered intravenously on day 1 every 21 days for 4 courses followed by 80 mg/m2 of paclitaxel administered intravenously on day 1 every week for 12 courses(AP-wP). The rate of pathological, clinical response and breast conserving surgery and adverse events (CTCAE ver.3.0) were analyzed in stage II /III breast cancer. Results: From December 2005 to August 2006, 40 planned patients have been enrolled. One patient canceled chemotherapy for interstitial pneumonia. 16 patients have finished their treatment, received surgery and are evaluable for response. Clinical response rate was 81.2% (50.0%CR; 31.2%PR). Stable disease and progressive disease occurred in 2 (12.5%) patients and 1 (6.3%) patient. Four patients (25%) had pathological complete response. Conclusions: Preliminary results indicate that the AP-wP regimen feasible and very active as induction chemotherapy of operable breast cancer. Updated data including evaluation of biological markers will be presented at the meeting.

No significant financial relationships to disclose.

Analysis of x-ray polarization to determine the three-dimensionally anisotropic velocity distributions of hot electrons in plasma produced by ultrahigh intensity lasers

A new polarization spectroscopy model has been developed to analyze energetic electrons distributed in a three-dimensional phase space. This model calculates the polarization degrees for a given line of sight. Time-dependent polarization degrees of Healpha line emitted from heliumlike chlorine ions was obtained for two different lines of sight by using three-dimensional electron velocity distributions provided with two-dimensional particle-in-cell simulations. These results demonstrate that the polarization degrees are sensitively dependent on the profile of the electron velocity distributions which are affected by the polarization of the laser pulse.

Multicenter, prospective study of radiotherapy without surgery after AC followed by weekly paclitaxel for patients with inflammatory breast cancer: SBCCSG-04 study

10783

Background: Inflammatory breast cancer (IBC) is a rare and aggressive disease with a dismal outcome. It is still an open debate whether surgery is beneficial for patients with IBC. This study was conducted to evaluate treatment results when patients were treated by chemotherapy and radiotherapy (CRT) alone. Methods: 52 pts with nonmetastatic IBC were enrolled for a prospective registration trial from 9/01–11/04. A diagnosis required the presence of erythema, ridging, or peau d’orange, with or without dermal lymphatic invasion (DLI). All patients were invited to participate for an experimental protocol; 4 cycles of AC and 12 cycles of weekly paclitaxel (80 mg/m2) followed by radiotherapy. In patients who did not agree to the protocol, the decision about treatment was left to the patients/investigators. The primary endpoint was distant-disease-free survival, and the further endpoints were locoregional relapse (LR) and overall survival. Results: The mean follow-up was 25.7 months. 24 pts (46.2%) were planned for the protocol, but one pt (4%) was receipt surgery. Otherwise, 18 (64%) out of 28 pts have accepted mastectomy. The 2-year distant-disease-free, LR, and overall survival in patients treated with and without the protocol was 35.2 vs 61.0% (HR = 2.4, 1.1–5.3) and 55.2 vs 83.6% (HR = 2.9, 1.1–7.8), respectively. Surgery was not associated with the risk of LR (p = 0.48). There was marginally worse prognosis in patients with DLI. Conclusions: There was a limitation because this comparison had not been conducted a randomized fashion. However, CRT alone would be a feasible treatment schedule for a moderate percentage of patients with IBC.

No significant financial relationships to disclose.

Fatal hepatitis B virus reactivation in a chronic myeloid leukemia patient during imatinib mesylate treatment

Reactivation of chronic hepatitis B virus (HBV) infection in patients undergoing chemotherapy is well-documented, but reactivation during imatinib mesylate treatment has not been reported. This study reports a 54-year-old man, without prior liver dysfunction but with chronic HBV infection, in whom fatal HBV reactivation occurred during treatment of chronic myeloid leukemia (CML) with imatinib mesylate. He developed fulminant hepatitis followed by marked elevation of HBV DNA polymerase, probably from the lymphocytopenic and immunosuppressive status induced by imatinib mesylate. Imatinib mesylate is widely used to treat CML patients. Although therapy with imatinib mesylate is generally well tolerated, the case presented here suggests that viral reactivation should be considered, even when using imatinib mesylate to treat CML.

Two States of the Triple Helix in the Thermal Transition of the Collagen Model Peptide (Pro-Pro-Gly)10

The collagen model peptide (Pro-Pro-Gly)10 is known to fold into a triple helix in solution. So far, the triple helix has been considered to exist as a single state. However, our previous study of (Pro-Pro-Gly)10 in solution has indicated the presence of two different states of the triple helix, a lower (HL) and a higher temperature state (HH). In the present study, these triple-helical states were investigated in more detail by NMR. Complete stereospecific assignments of the methylene protons of the proline residues were accomplished by the use of NOESY and TOCSY spectra. The temperature dependence of the 1H chemical shifts showed that the HL-to-HH thermal transition can be attributed to a conformational change of the first proline (Pro1) residues of the (Pro-Pro-Gly) triplets. Since TOCSY spectra with a 10 ms mixing-time confirmed a down puckering of these Pro residues in the HL state, but interconverting down and up puckerings in the HH state, the HL-to-HH thermal transition corresponds to conformational changes of the pyrrolidine rings of the Pro1 residues from an uniform down puckering to a more flexible state. The results confirm that thermal unfolding of the triple helix proceeds through the intermediate HH state.

[The new portable system for home enteral nutrition, Portermate, made a patient possible go out for a long time: report of a case]

The patient, who is received home enteral nutrition (HEN) for a long time in a day, has problems on moving all days. Now, we tried Portermate, which is new portable devices for HEN, in his clinical care. The patient is chronic pancreatitis, and his clinical problems becomes to be worse after he ate. He was under total enteral nutrition via jejunostomy. His clinical complications were almost controlled after HEN, but he has a few complains receiving enteral nutrition. He would not move easily, for an old HEN system was not compact to move. Portermate made him go everywhere he wanted any time. It extremely improved his QOL under HEN. He continues to use Portermate.

Cross-reactive mechanism for the false elevation of free triiodothyronine in the patients treated with diclofenac

We report three cases of patients exhibiting a false elevation of serum free triiodothyronine (FT3) as a result of a cross-reaction with diclofenac. The first case is a 66-yr-old woman with a long history of rheumatoid arthritis (RA). The patient was receiving diclofenac for the treatment of her RA. The patient was subsequently diagnosed as having thyroid papillary adenocarcinoma and received a subtotal thyroidectomy. After the operation, the patient exhibited postoperative hypothyroidism except for a gradual elevation of FT3. The other two patients also exhibited an elevated serum FT3 level after the administration of diclofenac. Serum FT3 levels in these patients decreased to normal or below normal after diclofenac administration was discontinued. In the first case, the elimination of immunoglobulin from the sera using polyethylene glycol precipitation did not reduce the FT3 level. In our hospital, Vitros ECi (enhanced chemiluminescence enzyme immunoassay) system and Vitros FT3 kit were used for FT3 assay. The patient's FT3 levels were normal or below normal when they were measured using other FT3 kits. FT3 was also detected when diclofenac was dissolved in a phosphate buffered saline. Therefore, we concluded that a cross-reaction between FT3 and diclofenac was the mechanism causing the false elevation of FT3 in these patients.

Stem cells find their niche

The concept that stem cells are controlled by particular microenvironments known as 'niches' has been widely invoked. But niches have remained largely a theoretical construct because of the difficulty of identifying and manipulating individual stem cells and their surroundings. Technical advances now make it possible to characterize small zones that maintain and control stem cell activity in several organs, including gonads, skin and gut. These studies are beginning to unify our understanding of stem cell regulation at the cellular and molecular levels, and promise to advance efforts to use stem cells therapeutically.

Calcium sensitization produced by G protein activation in airway smooth muscle

We determined whether activation of G proteins can affect the force developed for a given intracellular Ca(2+) concentration ([Ca(2+)]; i.e., the Ca(2+) sensitivity) by mechanisms in addition to changes in regulatory myosin light chain (rMLC) phosphorylation. Responses in alpha-toxin-permeabilized canine tracheal smooth muscle were determined with Ca(2+) alone or in the presence of ACh, endothelin-1 (ET-1), or aluminum fluoride (AlF; acute or 1-h exposure). Acute exposure to each compound increased Ca(2+) sensitivity without changing the response to high [Ca(2+)] (maximal force). However, chronic exposure to AlF, but not to chronic ACh or ET-1, increased maximal force by increasing the force produced for a given rMLC phosphorylation. Studies employing thiophosphorylation of rMLC showed that the increase in force produced by chronic AlF exposure required Ca(2+) during activation to be manifest. Unlike the acute response to receptor agonists, which is mediated solely by increases in rMLC phosphorylation, chronic direct activation of G proteins further increases Ca(2+) sensitivity in airways by additional mechanisms that are independent of rMLC phosphorylation.

A simplified defaecographic procedure for the assessment of faecal incontinence or obstructed defaecation

OBJECTIVE

Various types of defaecography have been reported for research purposes. A simplified method for clinical use has not been devised for the assessment of disordered defaecation. The aim of this study was to describe a simplified procedure of defaecography and evaluate its usefulness in the diagnosis of faecal incontinence or obstructed defaecation.

PATIENTS AND METHODS

Anorectal manometry and simplified defaecography were performed in 82 consecutive patients. The procedure of defaecography consisted of instillation into the rectum with a 100% weight per volume of barium in the sitting position through a Foley catheter with an inflated balloon, and several series of static radiograph at rest, during squeezing and straining according to deflation of the balloon.

RESULTS

Positive rate of barium leakage after barium insertion was significantly higher in incontinent patients than constipated or asymptomatic patients (P < 0.001, respectively). The degree of barium leakage was classified into mild in 18 patients with faecal incontinence, moderate in 4 and severe in 2. Constipated patients had more difficulty trying to expel a catheter than incontinent or asymptomatic patients (P=0.001, P=0.03). Twenty-four percent of patients with obstructed defaecation could not expel the balloon and 48% could not evacuate barium sulphate completely. The positive rate of morphological changes such as rectocele, internal intussusception and band formation was higher in constipated patients than incontinent or asymptomatic patients (P=0.01, P=0.04).

CONCLUSION

The grade of barium leakage or balloon prolapse reflected the severity of faecal incontinence. The ability in rectal emptying of the balloon or barium sulphate also correlated with the degree of outlet obstruction. The authors concluded that the present defaecographic technique was useful for the assessment of faecal incontinence or functional outlet obstruction, and recommend it due to its simplicity.

Right hepatic artery interruption and prostaglandin E1 in total or proximal pancreatectomy for pancreatobiliary malignancy

BACKGROUND/AIMS

Advanced hepato-biliary-pancreatic malignancy can frequently involve the hepatic artery. We evaluated the use of prostaglandin E1 in total or proximal pancreatectomy with the right hepatic artery interruption.

METHODOLOGY

A Consecutive seven of 117 patients (6.0%) in whom the right hepatic artery was interrupted and not reconstructed were reviewed retrospectively. Four of them received prostaglandin E1 (10-20 ng/kg/min) until the fifth postoperative day, while, the remaining three did not. The effect of prostaglandin E1 was compared concerning complication and hepatic function.

RESULTS

The right hepatic artery was intentionally resected because of cancer invasion in five patients with biliary tract carcinoma, while, accidentally transected in two with pancreatic carcinoma. Operative deaths did not occur. The biliary leakage was identified in one patient treated without prostaglandin E1. Although a marked rise in glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and lactate dehydrogenase levels was observed, hepatic dysfunction was successfully treated conservatively in all patients. The glutamic oxaloacetic transaminase and lactate dehydrogenase values were significantly lower (P < 0.05) in patients treated with prostaglandin E1 compared with those without prostaglandin E1.

CONCLUSIONS

The prostaglandin E1 infusion can be helpful for biliary anastomosis and hepatic function in radical hepato-biliary-pancreatic surgery with the right hepatic artery interruption.

Immunodepressants ameliorate normothermic ischemia injury to the rat liver by down-regulating tumor necrosis factor, not by alleviation of lipid peroxidative injury

Mechanisms by which immunodepressants (Cyclosporine, CsA; FK 506, FK; Azanthioprine, AZA) ameliorate warm ischemic injury of the liver were examined. Female Sprague-Dawley rats were subjected to 60-min of normothermic liver ischemia. Animals were assigned to one of four groups: group I, control with vehicle treatment; groups II, III, and IV, treatment with CsA (10 mg/kg), FK (1 mg/kg), and AZA (1 mg/kg), respectively. The immunosuppressive agents were given per os for 4 consecutive days prior to the induction of hepatic ischemia. In addition to a survival study, plasma levels of endotoxin, serum activities of tumor necrosis factor-alpha (TNF), plasma levels of phosphatidylcholine hydroperoxide (PCOOH) as a lipid peroxide, and serum alanine aminotransferase (ALT) were investigated in blood samples collected from the suprahepatic vena cava. A 7-day survival period was significantly higher in the immunosuppressed animals. Serum TNF levels were elevated and peaked at 3 h following reperfusion. When, the peak values were compared, the animals given immunodepressants had significantly lower levels of TNF (217.0 +/- 40.6 pg/ml for group I, 67.6 +/- 13.7 for group II, 87.9 +/- 28.3 for group III and 89.1 +/- 19.9 for group IV; Mean +/- SEM). Plasma PCOOH levels were also elevated following reperfusion, but with no statistical difference among the groups. Our data suggest that immunodepressants ameliorate warm ischemia/reperfusion injury through modulation of TNF production and not through a diminution of lipid peroxidative injury.

The distribution of PIG-A gene abnormalities in paroxysmal nocturnal hemoglobinuria granulocytes and cultured erythroblasts

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemolytic anemia that is characterized by a deficiency of glycosylphosphatidylinositol-anchored membrane proteins due to phosphatidylinositol glycan-class A (PIG-A) gene abnormalities in various lineages of peripheral blood cells and hematopoietic precursors. The purpose of our study was to clarify the distribution of PIG-A gene abnormalities among various cell lineages during differentiation and maturation in PNH patients. The expression of CD16b or CD59 in peripheral blood granulocytes or cultured erythroblasts from three Japanese PNH patients was analyzed using flow cytometry. PIG-A gene abnormalities in both cell types, including glycophorin A(+) bone marrow erythroblasts, were examined using nucleotide sequence analysis. The expression study of PIG-A genes from each patient was also performed using JY-5 cells.Flow cytometry revealed that the erythroblasts consisted of negative, intermediate, and positive populations in Cases 1 and 3 and negative and intermediate populations in Case 2. The granulocytes consisted of negative and positive populations in all three cases. DNA sequence analysis indicated that all the PNH cases had two or three types of PIG-A gene abnormalities, and that a predominant clone with an abnormal PIG-A gene was different in granulocytes and erythroblasts from Cases 2 and 3. Expression studies showed that all the mutations from the patients were responsible for the null phenotype.PIG-A gene abnormalities result in deficiencies of glycosylphosphatidylinositol-anchored proteins in PNH erythroblasts and granulocytes. The distribution of predominant PNH clones with PIG-A gene abnormalities is often heterogeneous between the cell types, suggesting that a clonal selection of PIG-A gene abnormalities occurs independently among various cell lineages during differentiation and maturation.

Destabilization of neutrophil NADPH oxidase by ATP and other trinucleotides and its prevention by Mg(2+)

Neutrophil NADPH oxidase (O(2)(-) generating enzyme) activated in a cell-free system was deactivated by dilution. When ATP was included in dilution the deactivation was further accelerated. The deactivation by dilution was biphasic, and the half-life of the enzyme was significantly shortened by ATP in each phase. ADP and AMP had little effect on the enzyme longevity while GTP and CTP had a similar effect to ATP. Staurosporine, a wide-range inhibitor of protein kinases, had no effect on ATP-induced deactivation, suggesting that the effect was not due to a protein phosphorylation. Mg(2+) addition largely prevented the deactivation by ATP. Chemical crosslinking of the activated oxidase prevented the deactivation by dilution and ATP, suggesting that the deactivation is caused by dissociation of the oxidase complex. Estimation of actin filament (F-actin) showed that the F-actin level was markedly reduced by addition of ATP. The ATP effect on the deactivation was not prominent in a semi-recombinant system which does not contain cytosol. These results suggest that ATP-induced deactivation is largely due to the chelation of Mg(2+) and are consistent with the concept that Mg(2+) stabilizes the oxidase complex by stabilizing F-actin.

Fiber arrangement of the rat splenic capsule with special reference to elastic fibers

The fiber arrangement of the rat splenic capsule was examined under scanning electron microscope (SEM) after selective removal by chemical maceration of capsule components, in conjunction with examination of thin sections using a transmission electron microscope (TEM). TEM findings were compared to those of the guinea-pig, mouse and dog. Serosal cells of the rat splenic capsule showed labyrinthic channels that consisted of expanded intercellular spaces and tunnel-like spaces or slits in the basal cytoplasm. The channels contained fascicles of collagenous fibrils, forming a loose net on an underlying elastic lamina of densely aggregated elastic fibers. The fibrous tunica was an intermingled layer of elastic and collagenous fibers and sparse interstitial cells. The fibrous components were arranged more densely in the external layer than in the internal layer of the capsule. The elastic lamina comprised the outermost layer of the fibrous tunica in the intertrabecular region, but was situated deep in the trabecular region. Outward branches of the lamina in the trabecular region were arranged in a spiral. Intrachannel fibrillar fascicles were continuous, via fenestrations in the elastic lamina, with thick fascicles of collagenous fibers. The elastic lamina may play a role in effective contraction of whole spleen. In the guinea-pig, mouse and dog, elastic fibers were fragmented and not arranged in laminae. Typical smooth muscle cells were abundant in the dog. The channel spaces in the serosal tunica are discussed from the viewpoint of extravascular lymphatic flow for circulation of the peritoneal serous fluid.

Lisinopril reduces left ventricular hypertrophy and cardiac polyamine concentrations without a reduction in left ventricular wall stress in transgenic Tsukuba hypertensive mice

This experiment was designed to determine how the angiotensin-converting enzyme inhibitor, lisinopril, acts on left ventricular wall stress and cardiac polyamine concentrations in Tsukuba hypertensive mice (THMs) carrying both human renin and angiotensinogen genes. Twelve-week-old THMs were treated with either lisinopril or hydralazine, or were left untreated, for 8 weeks. C57BL/6 mice of similar age were used as normal controls. Each group consisted of 14 mice. The systolic blood pressure of each mouse was measured once a week. Mice were euthanized at 20 weeks of age, and the left ventricular weight, left ventricular diameter, left ventricular wall stress, and left ventricular polyamine concentrations were measured. The systolic blood pressure of the untreated group was approximately 35 mmHg higher than that of the C57BL/6 mice. The left ventricular weight, left ventricular diameter, left ventricular wall stress, and left ventricular polyamine concentrations in the untreated group were significantly higher compared to those in the C57BL/6 mice. The lisinopril group had significantly decreased systolic blood pressure and other measurement items, except the left ventricular wall stress, in comparison with the untreated group. The hydralazine group also had significantly decreased systolic blood pressure and left ventricular wall stress when compared with the untreated group, but no significant differences in other measurement items when compared with the untreated group. These findings indicate that lisinopril reduces left ventricular hypertrophy and polyamine concentration without reducing left ventricular wall stress, and that simply decreasing blood pressure does not suppress left ventricular hypertrophy.

Direct interaction of actin with p47(phox) of neutrophil NADPH oxidase

The cell-free activation of human neutrophil NADPH oxidase is enhanced by actin, and actin filaments formed during activation are suggested to stabilize the oxidase. In an attempt to elucidate the mechanism, we examined the protein-protein interactions between actin and cytosolic components of the oxidase. Far-Western blotting using recombinant phox proteins showed that both alpha- and beta-actin interacted with p47(phox) and rac1, and weakly with rac2. A deletion mutant of p47(phox) proved that its C-terminal region was essential for the interaction. The dissociation constant (K(d)) for interaction between actin and p47(phox) was estimated to be 0.45 microM by surface plasmon resonance, and that between actin and rac1 or rac2 was 1.7 or 4.6 microM, respectively. Far-Western blotting using cytosol as a target showed an interaction between actin and endogenous p47(phox) and rac proteins. These results suggest that actin can directly interact with p47(phox) and possibly with rac in the cells.

Effects of pimobendan, a new cardiotonic agent, on contractile responses in single skeletal muscle fibres of the frog

Effects of a new cardiotonic agent, pimobendan, on contraction were investigated in single intact skeletal muscle fibres of the frog. Pimobendan increased twitch tension in a concentration-dependent manner regardless of the presence or absence of Ca2+ without any effect on tetanic tension, the resting membrane potential and the shape of the action potential. Pimobendan caused a further increase in twitch tension potentiated by caffeine (1 mM). Adenine, an inhibitor of Ca2+-induced Ca2+ release from the sarcoplasmic reticulum, inhibited twitch tension potentiated by caffeine but not by pimobendan, suggesting that twitch potentiation by pimobendan is not attributed to increases in Ca2+-induced Ca2+ release. Pimobendan failed to increase cAMP levels in the skeletal muscle, though forskolin significantly increased it without any effect on twitch tension. Contractile responses to high concentrations of caffeine and K+ were also potentiated by pimobendan. These results suggest that the potentiating effect of pimobendan on skeletal muscle contraction is mainly due to the increase in Ca2+ sensitivity to the contractile apparatus.

A case of congenital afibrinogenemia: fibrinogen Hakata, a novel nonsense mutation of the fibrinogen gamma-chain gene

Congenital afibrinogenemia due to a novel homozygous nonsense mutation of the fibrinogen gamma-chain gene, fibrinogen Hakata, was found in an 18-year-old Japanese girl who had received supplemental fibrinogen therapy since she was 4 months old. The plasma fibrinogen concentrations of the proband were measured as less than 10 mg/dl by a functional method and less than 17 mg/dl by an immunological method. Fibrinogen concentrations of her family were in the range of 94-164 mg/dl. The proband and her family had no other clinical symptoms. Genomic DNA of the proband and her family was isolated from leukocytes, and all exons of fibrinogen subunits and their intron/exon boundaries were analyzed. A genetic mutation, a guanine-to-thymine (G-to-T) transversion at the nucleotide position of 5860, was identified on exon 7 of the gamma-chain gene. This mutation changed the codon for the 231st residue of the gamma-chain from GAG (Glu) to TAG (stop). No other mutation was observed. Aalpha, Bbeta and gamma chains were observed in plasma of the heterozygous family members. However, only a trace amount of Aalpha chain and no gamma chain was detected in the plasma of the proband.

Relationship between force and regulatory myosin light chain phosphorylation in airway smooth muscle

We tested the hypothesis that increases in force at a given cytosolic Ca(2+) concentration (i.e., Ca(2+) sensitization) produced by muscarinic stimulation of canine tracheal smooth muscle (CTSM) are produced in part by mechanisms independent of changes in regulatory myosin light chain (rMLC) phosphorylation. This was accomplished by comparing the relationship between rMLC phosphorylation and force in alpha-toxin-permeabilized CTSM in the absence and presence of acetylcholine (ACh). Forces were normalized to the contraction induced by 10 microM Ca(2+) in each strip, and rMLC phosphorylation is expressed as a percentage of total rMLC. ACh (100 microM) plus GTP (1 microM) significantly shifted the Ca(2+)-force relationship curve to the left (EC(50): 0.39 +/- 0.06 to 0.078 +/- 0.006 microM Ca(2+)) and significantly increased the maximum force (104.4 +/- 4.8 to 120.2 +/- 2.8%; n = 6 observations). The Ca(2+)-rMLC phosphorylation relationship curve was also shifted to the left (EC(50): 1.26 +/- 0.57 to 0.13 +/- 0.04 microM Ca(2+)) and upward (maximum rMLC phosphorylation: 70.9 +/- 7.9 to 88.5 +/- 5. 1%; n = 6 observations). The relationships between rMLC phosphorylation and force constructed from mean values at corresponding Ca(2+) concentrations were not different in the presence and absence of ACh. We find no evidence that muscarinic stimulation increases Ca(2+) sensitivity in CTSM by mechanisms other than increases in rMLC phosphorylation.