Deletion of Tbc1d4/As160 abrogates cardiac glucose uptake and increases myocardial damage after ischemia/reperfusion.

BACKGROUND: Type 2 Diabetes mellitus (T2DM) is a major risk factor for cardiovascular disease and associated with poor outcome after myocardial infarction (MI). In T2DM, cardiac metabolic flexibility, i.e. the switch between carbohydrates and lipids as energy source, is disturbed. The RabGTPase-activating protein TBC1D4 represents a crucial regulator of insulin-stimulated glucose uptake in skeletal muscle by controlling glucose transporter GLUT4 translocation. A human loss-of-function mutation in TBC1D4 is associated with impaired glycemic control and elevated T2DM risk. The study's aim was to investigate TBC1D4 function in cardiac substrate metabolism and adaptation to MI. METHODS: Cardiac glucose metabolism of male Tbc1d4-deficient (D4KO) and wild type (WT) mice was characterized using in vivo [18F]-FDG PET imaging after glucose injection and ex vivo basal/insulin-stimulated [3H]-2-deoxyglucose uptake in left ventricular (LV) papillary muscle. Mice were subjected to cardiac ischemia/reperfusion (I/R). Heart structure and function were analyzed until 3 weeks post-MI using echocardiography, morphometric and ultrastructural analysis of heart sections, complemented by whole heart transcriptome and protein measurements. RESULTS: Tbc1d4-knockout abolished insulin-stimulated glucose uptake in ex vivo LV papillary muscle and in vivo cardiac glucose uptake after glucose injection, accompanied by a marked reduction of GLUT4. Basal cardiac glucose uptake and GLUT1 abundance were not changed compared to WT controls. D4KO mice showed mild impairments in glycemia but normal cardiac function. However, after I/R D4KO mice showed progressively increased LV endsystolic volume and substantially increased infarction area compared to WT controls. Cardiac transcriptome analysis revealed upregulation of the unfolded protein response via ATF4/eIF2α in D4KO mice at baseline. Transmission electron microscopy revealed largely increased extracellular matrix (ECM) area, in line with decreased cardiac expression of matrix metalloproteinases of D4KO mice. CONCLUSIONS: TBC1D4 is essential for insulin-stimulated cardiac glucose uptake and metabolic flexibility. Tbc1d4-deficiency results in elevated cardiac endoplasmic reticulum (ER)-stress response, increased deposition of ECM and aggravated cardiac damage following MI. Hence, impaired TBC1D4 signaling contributes to poor outcome after MI.

[Chronic pheochromocytoma-induced myocardial injuries: What should we expect from modern and classical echocardiographic tools?] / Apport du 2D strain et des outils échocardiographiques classiques pour la recherche d'anomalies myocardiques induites par l'exposition chronique à un phéochromocytome.

INTRODUCTION: Pheochromocytoma is a rare disease, which may manifest as severe cardiac complications. Apart from these situations, the "chronic" cardiac impact is not clearly defined. A cardiac MRI study suggests that these patients are carrying areas of fibrosis and foci of left ventricular myocarditis. Since these abnormalities are usually associated with altered left ventricular longitudinal systolic strain, we hypothesize that this strain is altered in patients with a "chronic" pheochromocytoma. METHOD: This retrospective case-control study was performed using patients from the Bordeaux University Hospital database, included between 2008 and 2016. We compared the left ventricular global longitudinal strain (GLS), radial and circumferential systolic strain and classic echocardiographic parameters between patients with pheochromocytoma and controls matched for age, sex, body mass index and systolic blood pressure. RESULTS: The analysis included 47 patients and 47 correctly matched controls. There were no statistically significant differences between the 2 groups in terms of GLS (-20.7±2.4% vs. -20.2±2.7%, P=0.40), radial strain, left ventricular mass or diastolic function. Left ventricular ejection fraction and circumferential strain were significantly higher in patients than in controls, with a significantly lower telediastolic diameter. CONCLUSION: No significant changes in GLS were observed in our pheochromocytoma patients, compared with controls. Several hypotheses may explain these results. The presence of fibrosis foci and areas of left ventricular myocarditis being associated with a poor cardiological prognosis, a systematic cardiac MRI could be discussed in these patients, until further studies are performed.

Effectiveness and persistence of Vedolizumab in patients with inflammatory bowel disease : results from the Belgian REal-LIfe study with VEdolizumab (Be-RELIVE).

BACKGROUND AND STUDY AIMS: Vedolizumab (VDZ) is a gutselective integrin inhibitor used to treat Crohn's disease (CD) and ulcerative colitis (UC). This retrospective study assessed effectiveness and treatment persistence of VDZ in a Belgian reallife cohort of CD and UC patients. PATIENTS AND METHODS: CD and UC patients from 15 Belgian centers, who started VDZ between 01/09/2015 and 31/06/2016 and attended ≥1 visit after the first VDZ infusion, were included. Data were collected before first infusion, at week (W)10, W14 (CD patients only), month (M)6 and last follow-up. Treatment response and remission rates (changes in disease activity scores) and treatment persistence (Kaplan-Meier analysis) were assessed. RESULTS: Of the 348 patients receiving at least one dose of VDZ, 325 (202 CD, 45 biologic-naïve; and 123 UC, 42 biologic-naïve) patients were included in data analyses. At M6, 87.6% (176/201) of CD and 86.1% (105/122) of UC patients were still on VDZ treatment, 75.6% (34/45) and 83.9% (26/31) achieved clinical response, and 66.7% (44/66) and 42.9% (15/35) were in remission. At M6 remission rates was significantly higher while response rates tended to be higher among biologic-naïve versus biologic-failure CD patients. CONCLUSIONS: VDZ offers an effective treatment option in real-life settings and treatment effectiveness appears higher in biologic-naïve versus biologic-failure CD patients. (Acta gastroenterol. belg., 2020, 83, 15-23).

[Alteration of left ventricular longitudinal systolic function in 2D-strain in primary aldosteronism: A new target organ damage marker]. / Altération de la fonction systolique longitudinale du ventricule gauche en strain bidimensionnel dans l'hyperaldostéronisme primaire : un nouveau marqueur d'atteinte d'organe cible.

OBJECTIVE: Primary hyperaldosteronism is the leading cause of secondary hypertension, and leads to frequent cardiovascular complications. Many studies have studied left ventricular geometry and function in this population, but longitudinal systolic function is still poorly described. METHODS: We studied 35 hypertensive patients with primary aldosteronism, and 35 with essential hypertension matched for age, sex, body mass index, and 24h blood pressure. Patients benefited from an echocardiography to measure the mass and the geometry of the left ventricle, left ventricle ejection fraction, systolic longitudinal, circumferential, and radial strain, and diastolic function. RESULTS: Compared to essential hypertensive patients, patients with primary aldosteronism presented a significantly higher left ventricular mass index and relative wall thickness (60.3±16.1g/m2 vs 47.3±18.6, P=0.003, and 0.44±0.08 vs 0.36±0.06, P=0.00005, respectively), as well as a significantly reduced longitudinal systolic strain (-17.8±3,4 vs -20.3±3,6%, P=0.004). There were no significant differences in the other parameters. CONCLUSIONS: Primary aldosteronism is associated with a deterioration of longitudinal systolic function of the left ventricle compared with essential hypertensive patients. This marker of cardiac damage, reproducible and easily available in routine could help for the screening of these patients.

From malignant hypertension to hypertension-MOD: a modern definition for an old but still dangerous emergency.

The prevalence of malignant hypertension has clearly fallen with the advent of anti-hypertensive medication but has remained stable over the past 30-40 years in spite of progress in diagnosis and management of hypertension. A diagnosis of malignant hypertension is usually based on the association of severely elevated blood pressure with a Keith and Wagener stage III or IV retinopathy. We believe that this definition can be reconsidered for several reasons. Although simple and pragmatic, this definition corresponds to a time when there were few techniques for assessment of hypertensive target organ involvement, and does not take into account involvement of kidney, brain and heart; whereas the overall prognosis largely depends on how much they are affected. On the contrary, the acute blood pressure level and especially diastolic should not be a hard diagnostic criterion as it does not itself constitute the prognosis of the condition. We propose to consider that malignant hypertension with retinopathy is only one of a number of possible presentation(s) of acute hypertension with multi organ damage (hypertension multi organ damage (MOD)) and that the recognition of these hypertensive emergencies, when retinopathy is lacking, be based on acute elevation of BP associated with impairment of at least three different target organs. The objective of a new and expanded definition is to facilitate recognition of these true emergencies. The condition is more common than usually perceived and would have a much worse prognosis than the usual forms of hypertension. Early recognition and management of hypertension-MOD are fundamental to any improvement in prognosis.

[Chronic renal insufficiency and cardiovascular disease]. / Insuffisance rénale chronique et maladie cardiovasculaire.

Renal insufficiency is frequently seen in patients with cardiovascular disease. In contrast, coronary artery disease is the leading cause of death in patients with renal impairment. The recognition of renal insufficiency is essential in these patients and preventive measures must be put in place to prevent the progression or onset of cardiovascular disease. In this article, we explain the methods to assess kidney function, the epidemiology of coronary heart disease in patients with renal impairment, risk factors conventional and non-conventional found in these patients and the main recommendations for their therapeutic care.

In situ experimental evidence of the fate of a phytodetritus pulse at the abyssal sea floor.

More than 50% of the Earth' s surface is sea floor below 3,000 m of water. Most of this major reservoir in the global carbon cycle and final repository for anthropogenic wastes is characterized by severe food limitation. Phytodetritus is the major food source for abyssal benthic communities, and a large fraction of the annual food load can arrive in pulses within a few days. Owing to logistical constraints, the available data concerning the fate of such a pulse are scattered and often contradictory, hampering global carbon modelling and anthropogenic impact assessments. We quantified (over a period of 2.5 to 23 days) the response of an abyssal benthic community to a phytodetritus pulse, on the basis of 11 in situ experiments. Here we report that, in contrast to previous hypotheses, the sediment community oxygen consumption doubled immediately, and that macrofauna were very important for initial carbon degradation. The retarded response of bacteria and Foraminifera, the restriction of microbial carbon degradation to the sediment surface, and the low total carbon turnover distinguish abyssal from continental-slope 'deep-sea' sediments.

Apoptosis in v-myc-transfected MSU-1.1 fibroblasts is induced by cell-matrix contact and differs from that of normal dermal fibroblasts.

In order to characterize a fibroblast cell line representing normal human skin fibroblasts in three-dimensional cultures, we compared the fibroblast line MSU-1.1, derived from human foreskin and immortalized by v-myc, to primary human dermal fibroblasts (NDF). Our results demonstrate that in contrast to NDF, all MSU-1.1 fibroblasts die within 3-4 d when cultured within three-dimensional contractile collagen matrices. Also, in contrast to NDF. MSU-1.1 cells die markedly in anchored collagen gels as well. Death is due to apoptosis and is attenuated by addition of antibodies against collagen-recognizing receptors alpha1beta1 and alpha2beta1. Apoptosis of NDF in collagen lattices was repressed by an inhibitor of caspase-1, which was ineffective on apoptosis of MSU-1.1. Further, apoptosis by MSU-1.l fibroblasts was also observed in anchored, i.e., restrained collagen lattices, an environment that supports proliferation of NDF.

Contraction-dependent apoptosis of normal dermal fibroblasts.

The mechanisms underlying the contraction-dependent apoptosis of primary fibroblasts are of prime importance in understanding anchorage-dependent survival/apoptosis of dermal fibroblasts. As integrins are essential extracellular matrix receptors in fibroblasts, their role in anchorage-dependent apoptosis/survival of fibroblasts was analyzed. Primary human fibroblasts displayed a marked reduction of apoptosis in mechanically relaxed collagen matrices in the presence of adhesion-blocking antibodies against alpha1beta1 or alpha2beta1. Anti-alphavbeta3 antibodies had a considerably weaker effect. In additional experiments RD cells, which lack alpha2 integrin, displayed no apoptosis in mechanically relaxed collagen matrices. Their susceptibility to apoptosis was restored after transfection with functional alpha2 integrin, and it could be blocked again by adhesion-blocking antibodies against alpha2beta1 integrin. Therefore we conclude that apoptosis of human primary fibroblasts in contractile collagen matrices is - at least in part - inhibited by adhesion-blocking anti-integrin antibodies, suggesting that the mode of apoptosis in this case is different from anoikis. Further, apoptosis in a mechanically relaxed collagen matrix could be abrogated by depolymerization of F-actin using cytochalasin D and also by disturbing actin-myosin interaction using 2,3-butanedione monoxime, indicating a possible dependence of apoptosis on mechanical forces and/or cell shape.

Is there a risk of cross-infection from laundered reusable bedpads?

The risk of cross-infection from reusable incontinence bedpads was assessed by determining their microbial content after one night's use by incontinent adults and after laundering using the standard foul wash procedure specified by the NHS Executive (NHS E, 1995) (which includes heat disinfection at 71 degrees C for 3 minutes). Measurements were made on a total of 145 bedpads from five different product designs. It was found that effective laundering destroyed all known pathogenic organisms, although some commensal flora were isolated in small numbers (mean 12.2 colony forming units/ml). It is concluded that laundering reusable incontinence pads using the foul wash procedure leaves pads safe for multiple patient reuse with no demonstrable risk of cross-infection.

Normal human primary fibroblasts undergo apoptosis in three-dimensional contractile collagen gels.

Apoptosis of primary fibroblasts was observed in vivo during wound healing in skin and is expected to occur in other organs as well; however, the environmental signal for induction of apoptosis in fibroblasts and the putative influence of cell-matrix interactions on the regulation of apoptosis remain to be identified. Here we provide evidence for the role of fibrillar collagen in this process, and demonstrate that normal human primary fibroblasts embedded in contractile collagen gels undergo apoptosis as shown by the appearance of cytoplasmatic histone-associated DNA fragments starting at day 1 of culture with a peak around days 2-4. This induction of apoptosis in primary fibroblasts seems to be specific for contractile collagen gels, because apoptosis of primary fibroblasts was neither observed in cells grown on culture dishes or on plastic dishes coated with collagen, nor observed in cells seeded in either anchored collagen gels or contractile fibrin gels. We therefore conclude that a distinct environment such as a contractile collagen matrix determines the susceptibility of normal primary fibroblasts to apoptosis.

Expression of highly active sex-inducing pheromone of Volvox carteri f. nagariensis in a mammalian cell system.

A cDNA fragment coding for the sex-inducing glycoprotein of Volvox carteri f. nagariensis was expressed in a mammalian cell system (baby hamster kidney (BHK) cells). The transfection product exhibited a specific biological activity intermediate between the natural pheromone of the strains Volvox carteri f. nagariensis and Volvox carteri f. weismannia. Immunoblot analysis showed that the sex-inducing activity was expressed as a set of three iso-glycoproteins (35, 34 and 31 kDa).

The choice of microscopes for use in genitourinary medicine clinics.

The current wide choice of microscopes and the use of the microscope as a diagnostic tool is discussed. The formation of images and the aberrations which occur with lenses and the ways in which these are corrected are described. The functions of eye pieces and illuminating systems are presented. The requirements for microscopes in every day use, research microscopes and portable microscopes are described, and suggestions made as to how these requirements may be fulfilled. Brief comments on the care and maintenance of microscopes are made, and a list of manufacturers and suppliers appended.

Comparative in vitro studies with 4-quinolone antimicrobials.

The minimal inhibitory concentrations (MICs) of nalidixic acid, pipemidic acid, cinoxacin, oxolinic acid, flumequine, pefloxacin, acrosoxacin, amifloxacin, norfloxacin, enoxacin, ofloxacin and ciprofloxacin were determined for a range of clinical isolates. MICs were determined using an agar dilution technique in Mueller-Hinton agar supplemented with 10% lysed horse blood. The inoculum used was approximately 10(4) colony forming units, contained in 10 microliters Mueller-Hinton broth, which was applied to the agar plates using a multipoint inoculator. Following inoculation, plates were incubated in conditions appropriate for the organisms under investigation. The MIC of each antimicrobial for each isolate examined was determined as the lowest concentration of the antimicrobial which completely inhibited growth of the inoculum. The minimum concentrations required to inhibit the growth of 50% (MIC50) and 90% (MIC90) of the organisms examined were also determined. All of the more recently synthesised 4-quinolones showed considerably greater activity than the parent compounds, nalidixic acid, pipemidic acid and cinoxacin, against the range of organisms used in this study. Ciprofloxacin and ofloxacin were the two most active of the 4-quinolones examined.

Rifampicin for non-tuberculous infections?

Large populations of rifampicin-sensitive strains of Mycobacterium tuberculosis have been exposed in vitro to changing concentrations of rifampicin (RIF) in line with changes in the blood level of the drug observed during treatment, and to much lower concentrations. Experiments in which the organism was exposed to either 7 or 14 days of cyclically-changing rifampicin concentrations have resulted in the elimination of the M. tuberculosis test strains without the emergence of RIF resistance. The significance of these laboratory findings is discussed in relation to the debate as to whether rifampicin should be used in short courses for the treatment of non-tuberculous infections or whether it should be withheld for fear of inadvertently generating rifampicin-resistant strains of tubercle bacilli. It is argued that the evidence for withholding rifampicin from use in short courses against non-tuberculous infections is slight.

The Compu-pet 100: a versatile dispenser-diluter for the mechanization of microbiological techniques.

The Compu-pet 100 diluter/dispenser is a versatile and accurate instrument which can be employed for a wide variety of microbiological tests and techniques. Time in performing tests is often more than halved when the diluter is used. Large numbers of tests can be performed with minimal fatigue.