Synthesis and Characterization of Conducting Copolymers of (S)‐2‐Methylbutyl‐2‐(3‐thienyl)acetate with Pyrrole and Thiophene

Polymerization of methylbutyl‐2‐(3‐thienyl)acetate (MBTA) was achieved by constant current electrolysis at low temperature. Subsequently, the syntheses of block copolymers of polyMBTA were accomplished in the presence of either pyrrole or thiophene by constant potential electrolysis. Moreover, the copolymer of MBTA with thiophene was obtained with constant potential electrolysis.

The synthesis of monomer MBTA.     

3D CT-Inclusive Deep-Learning Model to Predict Mortality,ICU Admittance,and Intubation in COVID-19 Patients

Journal of Digital Imaging - Chest CT is a useful initial exam in patients with coronavirus disease 2019 (COVID-19) for assessing lung damage. AI-powered predictive models could be useful to better...     

Presence in bovine enteropathogenic (EPEC) and enterohaemorrhagic (EHEC) Escherichia coli of genes encoding for putative adhesins of human EHEC strains

Enteropathogenic and enterohaemorrhagic Escherichia coli (EPEC and EHEC) infections are characterised by the formation of attaching and effacing lesions on intestinal epithelial cells. The first step of EPEC and EHEC pathogenesis involves the initial adherence of the bacterium to the intestinal epithelium. A collection of bovine EPEC and EHEC strains belonging to different serogroups was tested by colony blot hybridization with gene probes for putative adhesins (BFPA, LPFA, IHA, LIFA) of human EPEC and EHEC, and also for fimbrial and afimbrial adhesins (AFA8, F17, Cs31A) of bovine necrotoxigenic E. coli (NTEC). In the bovine EPEC and EHEC strains tested, sequences homologous to lifA, ihA, and lpfA genes were detected, sometimes in association with particular serogroups. Bovine 026 EPEC also possessed a sequence homologous to a gene of the c/p operon, coding for the CS31A adhesin, associated with bovine NTEC. Overall results showed that different genes encoding for putative adhesins of human EHEC strains are present in bovine EPEC and EHEC strains, but not one of them is present in all strains.     

Statins in risk-reduction and treatment of cancer

Statins, which are competitive inhibitors of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, reduce cholesterol blood levels and the risk of developing cardiovascular diseases and their related complications. In addition to this main activity, statins show pleiotropic effects such as antioxidant, anti-inflammatory and antiproliferative properties, with applications in many pathologies. Based on their antiproliferative properties, in vitro and in vivo studies have investigated their effects on various types of cancer (i.e., breast cancer, prostate cancer, colorectal cancer, ovarian cancer, lung cancer) with different genetic and molecular characteristics. Many positive results were obtained, but they were highly dependent on the physiochemical properties of the statins, their dose and treatment period. Combined therapies of statins and cytotoxic drugs have also been tested, and synergistic or additive effects were observed. Moreover, observational studies performed on patients who used statins for different pathologies, revealed that statins reduced the risk of developing various cancers, and improved the outcomes for cancer patients. Currently, there are many ongoing clinical trials aimed at exploring the potential of statins to lower the mortality and the disease-recurrence risk. All these results are the foundation of new treatment directions in cancer therapy.     

A new class of selective myocardial calcium channel modulators. 2. Role of the acetal chain in oxadiazol-3-one derivatives

In the framework of the continuing interest of this research group in the use of 8-aryl-8-hydroxy-8H-[1,4]thiazino[3,4-c][1,2,4]oxadiazol-3-ones (1) as calcium entry blockers, a number of acetals were synthesized and assayed "in vitro". All of them are structurally related to diltiazem and pyrrolobenzothiazines. The effect on the biological profile was measured by functional assays for a wide variety of acetal residues: saturated linear and branched chains, short and long unsaturated E and/or Z chains as well as benzyl and methylcyclohexyl residues. From selective assays on the most active derivative (5b) (EC(50) = 0.04 microM), which is 20 times more active than diltiazem (EC(50) = 0.79 microM), a muscarinic or adenosinic mechanism of action was excluded. A 3D QSAR model was obtained and validated with homologous literature data, and a virtual receptor scheme was derived for the unknown binding site. The following pharmacophoric features favorably affect the potency: one positively charged center, three lipophilic groups, and two hydrogen-bonding acceptor groups.     

The effect of age and diet on the ultrastructure of hymenopteran flight muscle

The changes in the ultrastructure of the flight muscles, with age and diet in Nasonia vitripeniss are described.

On the normal diet of dipteran puparia the principal age change is a loss of glycogen particles from around the mitochondria and myofibrils. The mitochondria are less tightly packed and there is some enlargement of the vesicles of the sarcoplasmic reticulum.

On a diet of 10 per cent sterile sucrose a 47 per cent increase in life-span occurs as compared with the puparia fed animals. In the aged sucrose fed animals there is a displacement of the mitochondria, and they contain inclusions with occasional myelin figures. There is a tendency for the cristae to be orientated to lie in the longitudinal plane. Glycogen deposits disappear from the myofibrils. In some cases there is a disorganisation of the myofilament structure of the muscle.

The age changes recorded are compared with work on flight muscle of other insect species. The significance of the changes with age and diet are discussed.     

Fibrin formation during asanguinous normothermic perfusion of the isolated rat liver

A progressive accumulation of fibrin in the small vessels of the isolated perfused rat liver was documented by both histological and autohistoradiographic techniques. These changes occurred initially in the sinusoids and later extended to the interlobular branches of the portal vein. Fibrin deposition was accompanied by a reduction of perfusion flow, an increase of the lactate-pyruvate ratio in the perfusion medium, and a depletion of liver tissue glycogen. All of these changes were prevented by adding streptokinase to the perfusing solution. Mechanisms leading to intravascular accumulation of fibrin and the possible involvement of this process in failure of prolonged liver preservation, hemorrhagic accidents following liver transplantation, and liver allograft rejection are discussed. The use of fibrinolytic agents for perfusion preservation of the isolated liver appears promising.

---

Résumé L'accumulation progressive de la fibrine dans les petits vaisseaux du foie isolé de rat, perfusé à l'aide d'un système modifié après Scholz, a été démontrée à l'aide des techniques histologiques et autohistoradiographiques. Dans un état initial on constate que les sinusoïdes sont afféctés, puis les modifications s'étendent vers les branches interlobulaires. La déposition de la fibrine a été accompagnée par la réduction du débit de perfusion, par l'accroissement du rapport lactate-pyruvate dans le milieu de perfusion et la diminution du glycogène tissulaire. Toutes ces modifications ont été prévenues par l'adjonction de la streptokinase dans le milieu de perfusion. Les mécanismes qui déterminent l'accumulation intravasculaire de la fibrine et leurs possibles implications dans l'échec de la conservation prolongée du foie, dans l'apparition des accidents hémorragiques du transplant hépatique aussi que dans la réaction de rejet des greffes sont mis en discussion. De même on fait des appréciations sur les perspectives offertes par l'utilisation des agents fibrinolytiques dans la conservation du foie.

     

On the gap effect for saccades evoked by electrical microstimulation of frontal eye fields in monkeys

To investigate the mechanisms of fixation disengagement and saccade initiation, we electrically stimulated the macaque frontal eye fields (FEF) while monkeys performed a visual fixation task. We tested the effect of introducing a temporal gap between fixation target offset and the onset of the electrical stimulus. We found that the duration of the gap had a pronounced effect on the probability of producing electrically evoked saccades at a given current level. The highest probability was found for gaps of 200 ms duration. There were also effects of gap duration on saccade latency and amplitude for most of the stimulation sites. The increase in saccade probability may be associated with lower current thresholds for evoking saccades.     

Molecular voting for glioma classification reflecting heterogeneity in the continuum of cancer progression

Gliomas, the most common brain tumors, are generally categorized into two lineages (astrocytic and oligodendrocytic) and further classified as low-grade (astrocytoma and oligodendroglioma), mid-grade (anaplastic astrocytoma and anaplastic oligodendroglioma), and high-grade (glioblastoma multiforme) based on morphological features. A strict classification scheme has limitations because a specific glioma can be at any stage of the continuum of cancer progression and may contain mixed features. Thus, a more comprehensive classification based on molecular signatures may reflect the biological nature of specific tumors more accurately. In this study, we used microarray technology to profile the gene expression of 49 human brain tumors and applied the k-nearest neighbor algorithm for classification. We first trained the classification gene set with 19 of the most typical glioma cases and selected a set of genes that provide the lowest cross-validation classification error with k=5. We then applied this gene set to the 30 remaining cases, including several that do not belong to gliomas such as atypical meningioma. The results showed that not only does the algorithm correctly classify most of the gliomas, but the detailed voting results also provide more subtle information regarding the molecular similarities to neighboring classes. For atypical meningioma, the voting was equally split among the four classes, indicating a difficulty in placement of meningioma into the four classes of gliomas. Thus, the actual voting results, which are typically used only to decide the winning class label in k-nearest neighbor algorithms, provide a useful method for gaining deeper insight into the stage of a tumor in the continuum of cancer development.