Oxidative stress-dependent MMP-13 activity underlies glucose neurotoxicity

Background

A complication of diabetes is neuropathy, a condition of sensory axon degeneration that originates in the epidermis. The mechanisms remain unknown but reactive oxygen species (ROS) have been implicated in this condition. In this study, we assessed the role of ROS and a candidate downstream target, MMP-13 in glucose-induced sensory axon degeneration in zebrafish and mice.

Hematopoietic growth factor expression and ATRA sensitivity in acute promyelocytic blast cells

Acute promyelocytic leukemia (APL) is a homogeneous subgroup of acute myeloid leukemias (AMLs) characterized by the presence of the t(15,17) translocation and the resulting promyelocytic myeloid leukemia/retinoic acid receptor alpha (PML/RAR alpha) fusion proteins. To date APL is the only AML that is sufficiently sensitive to all-trans retinoic acid's (ATRA) differentiating effect. In vivo ATRA alone achieves complete remission in most APL patients. However, failure or partial responses are observed and the molecular basis of the absence of ATRA response in these patients has not been determined. To gain insights in the cell growth and differentiation of APL cells, expression of hematopoietic growth factors (HGF) shown to be produced by leukemic cells (interleukin-1 beta [IL-1 beta], IL-6, tumor necrosis factor alpha (TNF alpha), granulocyte colony-stimulating factor [G-CSF], granulocyte- macrophage colony-stimulating factor [GM-CSF], and IL-3) was studied in 16 APL samples. Twelve APL cases expressed IL-1 beta, IL-6, and TNF alpha, but not G-CSF, GM-CSF, and IL-3. These cases achieved complete remission with ATRA therapy. The four remaining patients (either TNF alpha negative or G-CSF, GM-CSF or IL-3 positive) did not achieve complete remission with ATRA. In all cases, in vivo response to ATRA therapy was correlated to the in vitro differentiation effect of all- trans retinoic acid 10(-6) mol/L. Thus, ATRA differentiation induction was strongly correlated to the HGF expression (P < .0001). These results suggest that the presence or absence of HGF's expression by APL cells may contribute to the therapeutic effect of ATRA in this disease.     

Golgi retention of a trans-Golgi membrane protein, galactosyltransferase, requires cysteine and histidine residues within the membrane-anchoring domain.

Galactosyltransferase (GT; UDPgalactose:beta-D-N-acetylglucosaminide beta-1,4-galactosyltransferase, EC 2.4.1.22) is a type II membrane-anchored protein composed of a short N-terminal cytoplasmic tail, a signal/membrane-anchoring domain, and a stem region followed by a large catalytic domain including the C terminus. To identify the peptide segment and key amino acid residues that are critical for Golgi localization of GT, the expression vector pGT-hCG was designed to encode the entire GT molecule fused to the C-terminal region of human chorionic gonadotropin alpha subunit (hCG alpha) as a reporter. COS-1 cells transfected with pGT-hCG expressed the chimera in the Golgi region, as detected by immunofluorescence microscopy using anti-hCG antibodies. Two deletion mutants, delta tail and delta stem, which are lacking most of the N-terminal cytoplasmic tail or 10 amino acids immediately after the membrane-anchoring domain, were localized in the Golgi. Replacement mutations of the membrane-anchoring domain of GT showed that the second quarter of the transmembrane domain or Cys29-Ala30-Leu31-His32-Leu33 is necessary for GT to be retained in the Golgi. Furthermore, the point mutants Cys29----Ser29 and His32----Leu32 were partially transported to the plasma membrane, whereas an Ala30-Leu31----Phe30-Gly31 mutant was localized in the Golgi. Finally, a double mutant, Cys29/His32----Ser29/Leu32, was found to be transported efficiently to the plasma membrane. The signal-anchoring domain of the transferrin receptor, a type II plasma membrane protein, was then replaced by portions of the GT transmembrane domain. Although the Cys-Xaa-Xaa-His sequence by itself cannot retain the transferrin receptor in the Golgi, the cytoplasmic half of the transmembrane domain of GT was partially capable of retaining the transferrin receptor in the Golgi. These results suggest that the cytoplasmic (or N-terminal) half of the transmembrane domain of GT contributes to the Golgi retention signal and that particularly Cys29 and His32 in this region are critical for GT to be retained in the Golgi.     

Predictive factors of 5-year health assessment questionnaire disability in early rheumatoid arthritis

OBJECTIVE: To determine prognostic factors of disability in early rheumatoid arthritis (RA) and to investigate the radiological and functional course of the disease. METHODS: A total of 191 patients with early RA (diagnosed for less than one year) according to American College of Rheumatology criteria were followed prospectively for 5 years. At baseline and at endpoint, Stanford Health Assessment Questionnaire (HAQ) scores and radiological scores (Sharp's score modified by van der Heijde) were performed. Correlations between numerous baseline data and HAQ score at endpoint were analyzed, using nonparametric tests. A multilinear regression model was performed to select independent prognostic factors of HAQ disability. RESULTS: During the 5-year followup, mean HAQ decreased from 1.3 (+/- 0.7) to 0.6 (+/- 0.6). There were 98 (65.3%) patients with a score > 1 point at baseline, but only 46 (27.4%) after 3 years and 34 (21.8%) after 5 years. Moreover, 90% of the patients had an improvement of the disability score. Final HAQ disability was associated with baseline values of HAQ score, Pain, Ritchie index, tender joint count, Disease Activity Score, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and erosion. Multivariate analysis selected baseline HAQ score, Ritchie index, ESR, CRP, and presence of erosion as independent prognostic factors of HAQ disability. The probability cutoff in the logistic model was selected to minimize the sum of false positive and false negative values: negative predictive value = 92.71%, positive predictive value = 46.15%, p = 0.408. Sex, age, IgM and IgA rheumatoid factors, other tested autoantibodies, and HLA class II genes did not contribute significantly to prediction of the disability after 5 years. At baseline, mean scores were 3.6 units (+/- 7.7) for total radiological score, 1.7 (+/- 4.5) for erosion score, and 1.9 (+/- 3.7) for joint space narrowing score. After 5 years, they were 17.9 +/- 22.3, 6.9 +/- 9.5, and 11.0 +/- 15.4, respectively. No erosion was present at the start in 58.0% of patients, compared to 24.2% and 22.4% at 3 and 5 years. Global radiographic progression concerned 87 patients (55.8%) during the 5 years. CONCLUSION: During the first 5 years of RA, radiological damage increased progressively in half of the patients, whereas HAQ disability improved in most of them during the same period of time and could be predicted by baseline values of HAQ score, Ritchie index, ESR, CRP, and presence (or absence) of erosion.     

Fibrosis Progression According to Epithelial‐Mesenchymal Transition Profile: A Randomized Trial of Everolimus Versus CsA

Markers of epithelial‐mesenchymal transition (EMT) may identify patients at high risk of graft fibrogenesis who could benefit from early calcineurin inhibitor (CNI) withdrawal. In a randomized, open‐label, 12‐month trial, de novo kidney transplant patients received cyclosporine, enteric‐coated mycophenolate sodium (EC‐MPS) and steroids to month 3. Patients were stratified as EMT+ or EMT? based on month 3 biopsy, then randomized to start everolimus with half‐dose EC‐MPS (720 mg/day) and cyclosporine withdrawal (CNI‐free) or continue cyclosporine with standard EC‐MPS (CNI). The primary endpoint was progression of graft fibrosis (interstitial fibrosis/tubular atrophy [IF/TA] grade increase ≥1 between months 3–12) in EMT+ patients. 194 patients were randomized (96 CNI‐free, 98 CNI); 153 (69 CNI‐free, 84 CNI) were included in histological analyses. Fibrosis progression occurred in 46.2% (12/26) CNI‐free EMT+ patients versus 51.6% (16/31) CNI EMT+ patients (p = 0.68). Biopsy‐proven acute rejection (BPAR, including subclinical events) occurred in 25.0% and 5.1% of CNI‐free and CNI patients, respectively (p < 0.001). In conclusion, early CNI withdrawal with everolimus initiation does not prevent interstitial fibrosis. Using this CNI‐free protocol, in which everolimus exposure was relatively low and administered with half‐dose EC‐MPS, CNI‐free patients were overwhelmingly under‐immunosuppressed and experienced an increased risk of BPAR.

     

Lack of objective evidence of efficacy of laxatives in chronic constipation

Laxatives are commonly used to treat constipation and can be bought over-the-counter in many countries, although some preparations need to be prescribed by physicians. A meta-analysis was conducted to quantitatively evaluate the published evidence on the efficacy of laxatives in constipation. We found that large, well-controlled, published studies whose data were comparable were lacking. Of 250 articles, 35 met the inclusion criteria but only 11 yielded usable data (N = 375 patients on laxatives, 174 on placebo). There was an effect of laxatives on stool frequency (mean increase 1.9 stools per week) and stool weight (mean increase 476 g) but this was not clearly distinguishable from that of placebo therapies (1 stool and 434 g, respectively) in studies up to 4 weeks in duration. Similarly, studies of 5–12 weeks yielded no differences overall. These results cannot definitively rule out laxatives as an effective treatment, due to the poor published evidence. Better evidence is required to justify the continued expenditure of funds on laxatives by both patients and formularies.     

Stanozolol promotes lipid deposition in the aorta through an imbalance in inflammatory cytokines and oxidative status in LDLr knockout mice fed a normal diet

The aim of the study was to evaluate the effect of an anabolic steroid, stanozolol, in a model of atherosclerosis and to investigate the involvement of the modulation of the inflammatory cytokines and oxidative stress in vascular lipid deposition. Low‐density lipid receptor‐deficient (LDLr?/?) mice were fed a standard chow diet and were each week injected subcutaneously either saline (control C group) or 20 mg/kg stanozolol (S group). After 8 weeks, the levels of cholesterol, oxidized LDL (OxLDL) and cytokines were measured in plasma, lipid deposition in aorta was evaluated by en face analysis, and thiobarbituric acid‐reactive substances and oxidation protein were determined in liver. The S group demonstrated increases in vascular lipid deposition, triglycerides and non‐HDL cholesterol levels. Stanozolol increased tumour necrosis factor alpha (TNF‐α) and decreased interleukin‐10 as well as increased the TNF‐α/IL‐10 ratio. Furthermore, oxidative stress was observed in the S group, as indicated by an increase in the plasma OxLDL, as well as by lipid peroxidation and oxidation of proteins in the liver. Chronic treatment with stanozolol promoted lipid deposition in the LDLr^?/? mice that could be attributed to a modification of the circulating cytokine levels and systemic oxidative stress. Our results suggest that the anabolic steroid stanozolol in the absence of functional LDL receptors by increasing systemic inflammation and oxidative stress may increase the risk of development and progression of atherosclerosis.     

Exploring isoxazoles and pyrrolidinones decorated with the 4,6‐dimethoxy‐1,3,5‐triazine unit as human farnesyltransferase inhibitors

Unprecedented triazinyl‐isoxazoles were afforded via an effective cycloaddition reaction between nitrile oxides and the scarcely described 2‐ethynyl‐4,6‐dimethoxy‐1,3,5‐triazine as dipolarophile. The biological evaluation of the newly synthesized compounds showed that the inhibition of human farnesyltransferase by zinc complexation could be improved with triazine‐isoxazole moieties. The replacement of the isoxazole unit by a pyrrolidin‐2‐one was detrimental to the inhibitory activity while the pyrrolidin‐2‐thione derivatives conserved the biological potential. The potential of selected compounds to disrupt protein farnesylation in Chinese hamster ovary (CHO) cells transfected with pEGFP‐CAAX was also evaluated.     

Considération critique sur l’extension de la bipolarité, psychopathologie des mouvements d’humeur et de l’euphorie morbide

Objectives

From manic-depressive psychosis to bipolar spectrum, today's psychiatry allows us to observe a widening of bipolar criteria. This article aims at studying this evolution, its consequences with a critical look and the psychopathology of mood changes and morbid euphoria.

Methods

All of our considerations refer to current data on bipolar disorders (review with Medline and Science Direct) compared with studies from classical psychiatrists (Kraepelin, Ey) and various authors inspired by psychoanalysis (Freud, Racamier) and phenomenology (Binswanger, Tellenbach, Tatossian).

Results

Many contemporary authors encourage clinicians to detect bipolar disorders from symptoms, early signs and attenuated or atypical expressions. The concept of a widened spectrum is supposed to be closer to clinical reality and it would be an opportunity to diagnose this disease and its deleterious consequences better and thus to set up an appropriate therapy at an early stage. Other authors, on the other hand, deplore a dilution of bipolar disorders together with harmful diagnostic inflation around a concept that has become too heterogeneous to be effective, that subjugates or interferes with other pathologic entities in an excessive manner and abandoning a psychopathological approach. In this view, we shall analyze the nosographic shifts of bipolar disorders throughout the history of psychiatry, from manic-depressive psychosis to bipolar disorder and spectrum. We shall then scrutinize the autonomy and limitations related to bipolar disorders as opposed to normality, confusing clinical presentations and other major mental diseases: Psychosis, depression, pathological personality, anxiety, impulse-control, attention deficit-hyperactivity, addiction and psycho-organic disorders. This work shall first introduce a discussion on the concept of bipolar disorders for children, and then through the case of some historical figures. Then we will deal with the contemporary social factors that are currently furthering the extension of this diagnosis. Last, this article sheds a light on psychopathological specificities of mania – the cornerstone in bipolar disorders – mood changes and morbid euphoria.

Conclusion

We think that classic psychiatry, phenomenology and psychoanalysis would act as a guiding light through this debate and could help the clinician in this daily practice. Mood variations require a careful clinical observation and a rigorous set of interpretation, before being specified too excessively or hastily as a symptom of a real bipolarity.