Trimetazidine improves left ventricular function in diabetic patients with coronary artery disease: a double-blind placebo-controlled study

Background

Patients with diabetic cardiomyopathy have an impaired myocardial glucose handling and distal distribution of coronary atherosclerosis. Trimetazidine, an anti-ischemic metabolic agent, improves myocardial glucose utilization though inhibition of fatty acid oxidation. Aim of the present study was to evaluate whether the metabolic effect of trimetazidine on left ventricular function in patients with diabetic cardiomyopathy.

Methods

32 patients (24 males and 8 females, mean (SE) age = 67 ± 6 years) with type 2 diabetes and ischemic cardiomyopathy were randomized to receive either trimetazidine (20 mg, t.d.s.) or placebo (t.d.s.) for six months in a randomized parallel study. Patients performed an echocardiogram at baseline and after 6 months.

Results

Demographic data were comparable between the two groups. After six month baseline left ventricular end-diastolic diameters increased from 62.4 ± 1.7 to 63 ± 2.1 mm in the placebo group, while decreased from 63.2 ± 2.1 to 58 ± 1.6 mm (p < 0.01 compared to baseline) in the trimetazidine group. Compared to baseline, left ventricular ejection fraction increased by 5.4 ± 0.5% (p < 0.05) in the trimetazidine group while remained unchanged in the placebo group -2.4 ± 1.1% (NS), p < 0.01 between groups. A significant improvement in wall motion score index and in the E/A wave ratio was detected in patients treated with trimetazidine, but not in those receiving placebo.

Conclusion

in diabetic patients with ischemic heart disease trimetazidine added to standard medical therapy has beneficial effect on left ventricular volumes and on left ventricular ejection fraction compared to placebo. This effect may be related to the effect of trimetazidine upon cardiac glucose utilization.     

An unusual mutation in RECQ4 gene leading to Rothmund-Thomson syndrome

Rothmund-Thomson syndrome (OMIM #268400) is a severe autosomal recessive genodermatosis: characterised by growth retardation, hyperpigmentation and frequently accompanied by congenital bone defects, brittle hair and hypogonadism. Mutations in helicase RECQ4 gene are responsible for a subset of cases of RTS. Only six mutations have been reported, thus, far and each affecting the coding sequence or the splice junctions. We report the first homozygous mutation in RECQ4 helicase: 2746-2756-delTGGGCTGAGGC in IVS8 responsible for the severe phenotype associated with RTS in a Malaysian pedigree. We report also a 5321 G-->A transition in exon 17 and the updated list of the RECQ4 gene mutations.     

Cervical and peritoneal fluid cytology of uterine sarcomas

OBJECTIVE: To study the cytologic features of uterine sarcoma. STUDY DESIGN: The pathology records of 102 patients with uterine sarcoma were reviewed. Four patients, including one case of leiomyosarcoma (LMS), one high grade stromal sarcoma (HGSS) and two malignant mixed müllerian tumor (MMMT), had abnormal cervical and/or peritoneal cytologic findings. Three abnormal cervical smears and two abnormal peritoneal fluids from these patients, including immunohistochemically stained sections of cell block, were reviewed. RESULTS: The diagnostic cells appeared in clusters or in isolation. They had enlarged and hyperchromatic nuclei. Occasional mitotic figures were seen. The cells were considered suspicious for malignancy in cervical smears of HGSS and in the peritoneal fluid of LMS. Adenocarcinoma cells were identified in both the cervical smear and peritoneal fluid of one patient with MMMT. Atypical cells were found in another patient with MMMT. CONCLUSION: Positive cervical or peritoneal cytology is uncommonly detected in association with uterine sarcomas. Even when abnormal cells are found, it may be difficult to give a definitive diagnosis of uterine sarcoma based directly on the cytomorphologic characteristics of cervical or peritoneal smears. However, such a possibility should be kept in mind by the cytopathologist to avoid missing the diagnosis.     

Hagen's glands of the parasitic wasp Diachasmimorpha longicaudata (Hymenoptera: Braconidae): ultrastructure and the detection of entomopoxvirus and parasitism-specific proteins

Hagen's glands of males of the parasitic wasp Diachasmimorpha longicaudata (Hymenoptera: Braconidae) secrete compounds that are involved in courtship and defense. Like the poison glands of female wasps, the Hagen's glands are secretory, membranous, and of ectodermal origin. The poison glands contain the symbiotic entomopoxvirus, DlEPV and the parasitism-specific protein, PSP 24. DlEPV proteins were detected in homogenates of male wasps. Our goal was to describe the ultrastructure of the Hagen's glands and determine whether they contain DlEPV virions and/or proteins as well as PSP 24. The Hagen's glands are bilateral and each consists of 12-16 tubules arranged in two clusters. In cross-section, a tubule has three zones that enclose a central cuticle-lined lumen. The outermost zone consists of aggregates ('islands') of small vesicles, interconnected by narrow ductules that lead to large cuticle-lined ducts, which transport electron-dense material to the lumen prior to its release from the gland. Large vesicles in Zone 2 and a thick layer of ribosomes and rough endoplasmic reticula in Zone 3 are the likely sites of storage and protein synthesis, respectively. While DlEPV virions were not seen in the Hagen's gland, DlEPV and PSP 24 proteins were present.     

Within-night variation in respiratory effort preceding apnea termination and EEG delta power in sleep apnea

We studied the within-night variability of themaximum esophageal pressure deflection before apnea termination(DP_max) in nine patients withsevere obstructive sleep apnea as an index of the arousal threshold andthe mean electroencephalogram (EEG) delta power for each 30 s as anindex of the timing of sleep cycles. Periodicity in the time variationof delta power and DP_max was analyzed by determining their power spectral density and their relationship determined by cross correlation.DP_max and delta power variedcyclically and in phase with a major periodicity (major peak in powerspectral density) of 117.6 ± 8.8 (SE) min. The correlation betweenthe values of DP_max and deltapower was significant (P < 0.001) ineach subject (mean r = 0.47 ± 0.03), and the coherence betweenDP_max and delta power at theirdominant frequency was high. Within cycles of non-rapid-eye-movementsleep, DP_max and delta powerincreased, reaching peak values on average at or after midcycle. Thesefindings suggest that the arousal threshold to airway occlusion inpatients with obstructive sleep apnea varies cyclically during thenight synchronous to the underlying cycles of sleep.

     

The allocation and differentiation of mouse primordial germ cells.

Analysis of the lineage potency of epiblast cells of the early-streak stage mouse embryo reveals that the developmental fate of the cells is determined by their position in the germ layer. Epiblast cells that are fated to become neuroectoderm can give rise to primordial germ cells (PGCs) and other types of somatic cells when they were transplanted to the proximal region of the epiblast. On the contrary, proximal epiblast cells transplanted to the distal region of the embryo do not form PGCs. Therefore, the germ line in the mouse is unlikely to be derived from a predetermined progenitor population, but may be specified as a result of tissue interactions that take place in the proximal epiblast of the mouse gastrula. The initial phase of the establishment of the PGC population requires, in addition to BMP activity emanating from the extraembryonic ectoderm, normal Lim1 and Hnf3beta activity in the germ layers. The entire PGC population is derived from a finite number of progenitor cells and there is no further cellular recruitment to the germ line after gastrulation. The XX PGCs undergo X-inactivation at the onset of migration from the gut endoderm and re-activate the silenced X-chromosome when they enter the urogenital ridge. Germ cells that are localised ectopically in extragonadal sites do not re-activate the X-chromosome, even when nearly all germ cells in the fetal ovary have restored full activity of both X-chromosomes. XXSxr germ cells can re-activate the X-chromosome in the sex-reversed testis, suggesting that the regulation of X-chromosome activity is independent of ovarian morphogenesis.     

Cell cycle -dependent proteolysis in plants. Identification Of the destruction box pathway and metaphase arrest produced by the proteasome inhibitor mg132

It is widely assumed that mitotic cyclins are rapidly degraded during anaphase, leading to the inactivation of the cell cycle-dependent protein kinase Cdc2 and allowing exit from mitosis. The proteolysis of mitotic cyclins is ubiquitin/26S proteasome mediated and requires the presence of the destruction box motif at the N terminus of the proteins. As a first attempt to study cyclin proteolysis during the plant cell cycle, we investigated the stability of fusion proteins in which the N-terminal domains of an A-type and a B-type tobacco mitotic cyclin were fused in frame with the chloramphenicol acetyltransferase (CAT ) reporter gene and constitutively expressed in transformed tobacco BY2 cells. For both cyclin types, the N-terminal domains led the chimeric cyclin-CAT fusion proteins to oscillate in a cell cycle-specific manner. Mutations within the destruction box abolished cell cycle-specific proteolysis. Although both fusion proteins were degraded after metaphase, cyclin A-CAT proteolysis was turned off during S phase, whereas that of cyclin B-CAT was turned off only during the late G2 phase. Thus, we demonstrated that mitotic cyclins in plants are subjected to post-translational control (e.g., proteolysis). Moreover, we showed that the proteasome inhibitor MG132 blocks BY2 cells during metaphase in a reversible way. During this mitotic arrest, both cyclin-CAT fusion proteins remained stable.     

Role of calcium in signal transduction during the hypersensitive response caused by basidiospore-derived infection of the cowpea rust fungus

The hypersensitive response (HR) of disease-resistant plant cells to fungal invasion is a rapid cell death that has some features in common with programmed cell death (apoptosis) in animals. We investigated the role of cytosolic free calcium ([Ca2+]i) in the HR of cowpea to the cowpea rust fungus. By using confocal laser scanning microscopy in conjunction with a calcium reporter dye, we found a slow, prolonged elevation of [Ca2+]i in epidermal cells of resistant but not susceptible plants as the fungus grew through the cell wall. [Ca2+]i levels declined to normal levels as the fungus entered and grew within the cell lumen. This elevation was related to the stage of fungal growth and not to the speed of initiation of subsequent cell death. Elevated [Ca2+]i levels also represent the first sign of the HR detectable in this cowpea-cowpea rust fungus system. The increase in [Ca2+]i was prevented by calcium channnel inhibitors. This effect was consistent with pharmacological tests in which these inhibitors delayed the HR. The data suggest that elevation of [Ca2+]i is involved in signal transduction leading to the HR during rust fungal infection.     

Minimal aerobic sludge retention time in biological phosphorus removal systems

The methodology for determination of the minimally required aerobic sludge retention time (SRTminaer) in biological phosphorus removal (BPR) systems is presented in this article. Contrary to normal biological conversions, the BPR process is not limited by a SRTmin resulting from the maximum growth rate of the organisms. This is because the aerobic SRT should be long enough to oxidize the amount of poly-hydroxy-alkanoates (PHA) stored in the anaerobic phase. This means that the SRTminaer will primarily depend on the PHA conversion kinetics and the maximal achievable PHA content in the cell (storage capacity). The model for the prediction of the minimally required aerobic SRT as a function of kinetic and process parameters was developed and compared with experimental data used to evaluate several operational aspects of BPR in a sequencing batch reactor (SBR) system. The model was proved as capable of describing them satisfactorily.Copyright 1998 John Wiley & Sons, Inc.     

Innervation regulates the metamorphic fates of larval abdominal muscles in the moth, Manduca sexta

 With the onset of metamorphosis, the abdominal muscles of the moth, Manduca sexta, follow one of three developmental fates: maintenance, respecification, or death. The maintained muscles retain their larval size and morphology throughout adult development. The respecified and dying muscles dedifferentiate, which involves regression, nuclear degeneration, and myofibril breakdown. Nuclei in both dying and respecified muscles also proliferate. The amount of nuclear degeneration is greater in the dying muscle fibers, and the amount of nuclear proliferation is greater in the respecified muscles. Four to ten days after pupation, the sizes of the respecified muscles stabilize while the dying muscles are lost. During regression, a subset of the respecified muscle fibers die. The surviving respecified muscle fibers grow and differentiate during the last half of adult development. In respecified muscles, denervation triggers an increased amount of nuclear degeneration and a decreased amount of nuclear proliferation. As a result, denervated respecified fibers experience increased muscle regression including an increased loss of muscle fibers and sometimes muscle death. Surviving respecified fibers still grow and differentiate yet are only 5 to 12% of the control size. Denervation triggers dedifferentiation in maintained muscles, resulting in fiber loss and occasionally muscle death. The percentage of fibers which dedifferentiate varies between different muscles. Denervation also triggers nuclear proliferation, with the amount of nuclear proliferation correlated with the extent of dedifferentiation of the individual muscle fibers. The dedifferentiated maintained fibers subsequently undergo differentiation in the absence of muscle growth. Received: 10 July 1997 / Accepted: 21 April 1998