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Previous research show that conventional CAD B-Rep methods are highly inefficient to design large lattice structures composed of several thousands of geometric primitives describing struts [2,3]. This paper aims at proposing a method for slicing directly a lattice structure represented as a skeleton: a set of struts connecting nodes, where radius can be constant (cylinder) or linear (cones). The contribution of this method is twofold (1) efficiency: the CAD B-Rep representation is replaced with the skeleton representation which is robust and requires very low resources to be generated. (2) Accuracy: The method generates the explicit and exact geometry of layers with analytic curves, enabling the export into layers with polygons having an arbitrary accuracy.

Background/objective: The COVID-19 epidemic is particularly serious in older adults. The symptomatology and epidemic profile remain little known in this population, especially in disabled oldest-old people with chronic diseases living in nursing homes. The objective of the present study was to comprehensively describe symptoms and chronological aspects of the diffusion of the SARS-CoV-2 virus in a nursing home, among both residents and caregivers., Design: Five-week retrospective cohort study., Setting: A middle-sized nursing home in Maine-et-Loire, west of France., Participants: Eighty-seven frail older residents (87.9 ± 7.2years; 71 % female) and 92 staff members (38.3 ± 11.7years; 89 % female) were included., Measurements: Mass screening for SARS-CoV-2 was performed in both residents and staff. Attack rate, mortality rate, and symptoms among residents and staff infected with SARS-CoV-2 were recorded., Results: The attack rate of COVID-19 was 47 % in residents (case fatality rate, 27 %), and 24 % in staff. Epidemic curves revealed that the epidemic started in residents before spreading to caregivers. Residents exhibited both general and respiratory signs (59 % hyperthermia, 49 % cough, 42 % polypnea) together with geriatric syndromes (15 % falls, 10 % altered consciousness). The classification tree revealed 100 % COVID-19 probability in the following groups: i) residents younger than 90 with dyspnea and falls; ii) residents older than 90 with anorexia; iii) residents older than 90 without anorexia but with altered consciousness. Finally, 41 % of staff members diagnosed with COVID-19 were asymptomatic., Conclusions: The pauci-symptomatic expression of COVID-19 in older residents, together with the high prevalence of asymptomatic forms in caregivers, justifies mass screening in nursing homes, possibly prioritizing residents with suggestive combinations of clinical signs including dyspnea, falls, anorexia and/or altered consciousness., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Vitamin D insufficiency is associated with brain changes, and cognitive and mobility declines in older adults., Objective: Our objective was to investigate in older adults whether vitamin D insufficiency<50nmol/L was associated with thinner cingulate cortex, a brain area related to cognitive functions influenced by vitamin D., Methods: Two hundred and fifteen Caucasian older community-dwellers (mean±SD, 72.1±5.5years; 40% female) received a blood test and brain MRI. The thickness of perigenual anterior cingulate cortex, midcingulate cortex and posterior cingulate cortex was measured using FreeSurfer from T1-weighted MR images. Age, gender, education, BMI, mean arterial pressure, comorbidities, use of vitamin D supplements or anti-vascular drugs, MMSE, GDS, IADL, serum calcium and vitamin B9 concentrations, creatinine clearance were used as covariables., Results: Participants with vitamin D insufficiency (n=80) had thinner total cingulate thickness than the others (24.6±1.9mm versus 25.3±1.4mm, P=0.001); a significant difference found for all 3 regions. Vitamin D insufficiency was cross-sectionally associated with a decreased total cingulate thickness (β=- 0.49, P=0.028). Serum 25OHD concentration correlated positively with the thickness of perigenual anterior (P=0.011), midcingulate (P=0.013) and posterior cingulate cortex (P=0.021)., Conclusion: Vitamin D insufficiency was associated with thinner cingulate cortex in the studied sample of older adults. These findings provide insight into the pathophysiology of cognitive and mobility declines in older adults with vitamin D insufficiency., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Introduction: Antiphospholipid syndrome is an autoimmune disorder causing venous and arterial thrombosis. Acute coronary complications are rare but potentially dramatic., Case Report: We report a 39-year-old woman who presented with an acute anterior myocardial infarction after intravenous corticosteroids as part of the treatment of lupus arthritis and revealing antiphospholipid syndrome. Emergency coronary angiography was performed with drug-eluting stent angioplasty despite the need for anticoagulation and dual antiplatelet therapy., Conclusion: Antiplatelet and anticoagulant therapy management is pivotal in patients with antiphospholipid syndrome and acute coronary syndrome to prevent thrombosis recurrence., (Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.)

Unlike hydroxyurea, the CTP synthetase inhibitor acivicin and, to a lesser extent, two other inhibitors of CTP synthesis, increased the phosphorylation and anti-HIV-1 activity of 3TC in PHA-P-activated PBMC. These data suggest that to improve the antiretroviral activity of 3TC, it may be worth focusing on inhibition of CTP synthesis.

We studied interactions in vivo between the cytosolic muscle isoform of creatine kinase (M-CK) and the muscle isoform of 2-phospho-D-glycerate hydrolyase (beta-enolase) in muscle sarcoplasm by incubating glycerol-skinned fibres with FITC-labelled beta-enolase in the presence or absence of free CK. A small amount of bound beta-enolase was observed in the presence of large concentrations of CK. The mobility of enolase was measured in cultured satellite cells by modulated-fringe-pattern photobleaching. FITC-labelled beta-enolase was totally mobile in both the presence and the absence of CK but its diffusion coefficient was slightly lower in the presence of CK. This suggests a weak interaction in vivo between enolase and CK.

Modulated fringe pattern photobleaching (MFPP) was used to measure the translational diffusion of microinjected fluorescein isothiocyanate (FITC)-labeled proteins of different sizes in the cytoplasm of cultured muscle cells. This technique, which is an extension of the classical fluorescence recovery after photobleaching (FRAP) technique, allows the measurement of the translational diffusion of macromolecules over several microns. Proteins used had molecular masses between 21 and 540 kDa. The results clearly indicated that the diffusivity of the various proteins is a decreasing function of their hydrodynamic radius. This decrease is more rapid with globular proteins than with FITC-labeled dextrans (, Biophys. J. 70:2327-2332), most likely because, unlike globular proteins, dextrans are randomly coiled macromolecules with a flexible structure. These data do not exclude the possibility of a rapid diffusion over a short distance, unobservable with our experimental set-up, which would take place within the first milliseconds after bleaching and would correspond to the diffusion in restricted domains followed by impeded diffusion provoked by the network of microtubules, microfilaments, and intermediate filaments. Thus our results may complement rather than contradict those of Verkman and collaborators (, J. Cell Biol. 138:1-12). The biological consequence of the size-dependent restriction of the mobility of proteins in the cell cytoplasm is that the formation of intracellular complexes with other proteins considerably reduces their mobility.

Glycerol-skinned skeletal muscle fibres retain the defined sarcomeric structure of the myofibrils. We show here that a small fraction of two enzymes important for energy metabolism, the cytosolic muscle isoform of creatine kinase (EC 2.7.3.2), MM-creatine kinase (MM-CK), and enolase (EC 4.2.1.11), remains bound to skinned fibres. CK is slowly exchangeable, whereas enolase is firmly bound. Two-dimensional gel electrophoresis followed by Western blot analyses demonstrates that both alpha (ubiquitous) and beta (muscle-specific) subunits of enolase are present in these preparations. Enolase and CK were co-localized at the M-band of the sarcomeres, as observed by indirect immunofluorescence and confocal microscopy. Cross-linking experiments were performed on skinned fibres with three bifunctional succinimidyl esters of different lengths and yielded a protein complex of 150 kDa that reacted with antibodies directed against either M-CK or beta-enolase. The cross-linking efficiency was greatest for the longest reagent and zero for the shortest one. The length of the cross-linker giving a covalent complex between the two enzymes does not support the notion of a direct interaction between M-CK and enolase. This is the first demonstration of the presence of an enzyme of energy metabolism other than CK at the M-band of myofibres.

Determination of experimental conditions which allow the evaluation of the variations in the ratio of non polymerized and polymerized forms of actin and tubulin during the reorganization of the cytoskeletal cell system is of most valuable importance. In order to prepare cell homogenates which would reflect the in vivo situation, we tested in vitro a lysis medium which stabilized both microfilaments and microtubules, which were determined by DNase inhibition assays and colchicine binding assays respectively. This lysis medium containing 10 mM potassium phosphate, 1mM magnesium chloride, 5 mM EGTA, 1 M hexylene glycol, 1% Triton X-100, pH 6.4, used at 4 degrees C a) diffused rapidly into the cells; b) did not denature actin and tubulin; c) did not displace the equilibrium between non polymerized and polymerized forms of actin and tubulin, allowing biochemical assays on cell homogenates; d) blocked the evolution of the cytoskeletal system and permitted structural studies; e) and allowed the decoration of microfilaments by heavy meromyosin.

Dinitrophenylation of rabbit muscle and yeast glyceraldehyde-3-phosphate dehydrogenases modifies only SH groups. The rabbit muscle apoenzyme loses 75% of its original activity upon dinitrophenylation of two SH groups per tetramer whereas the yeast apoenzyme is totally inactivated under the same conditions. Dinitrophenylation of the active-site cysteine-149 of rabbit muscle and yeast holoenzymes results in an loss of activity corresponding to a 'half-of-the-sites' and a 'full-sites' reactivity, respectively. Determination of the sulphydryl content of the modified enzymes shows an unmasking of the cysteine residues of the dinitrophenylated rabbit muscle apoenzyme which is not observed for the yeast protein. However, conformational changes are revealed for both dinitrophenylated apoenzymes by differential absorption spectroscopy or by limited proteolysis. Sulphydryl group unmasking is not observed after modification of the cysteine residues of the rabbit muscle holoenzyme but it does occur when dinitrophenylation is performed in the presence of two moles NAD+/mole rabbit muscle enzyme. Although the apoenzyme is sensitive to an induced conformational change, our results favour symmetrical structures for both yeast apo and holo enzymes. The bis-dinitrophenylated rabbit muscle apoenzyme presents all the characteristics of an asymmetrical structure; however, it is not possible to deduce whether this symmetry is due to the chemical modification or whether it preexists in the native apoenzyme. The results of the dinitrophenylation of the rabbit holoenzyme, however, indicate that this enzyme possesses an asymmetrical structure.

Chemical modification of cystein 149 residues from yeast apo-glyceraldehyde-3-phosphate dehydrogenase either by iodoacetamidonaphtol or N-(4-dimethylamino-3,5-dinitrophenyl) maleimide results in the disappearance of free sulfhydryl groups according to "full sites reactivity", whereas loss of the dehydrogenase activity occurs following "half of the sites reactivity". Chemical modification of the same cystein residues of the rabbit muscle apoenzyme by N-(4-dimethylamino-3,5-dinitrophenyl) maleimid shows that both loss of activity and disappearance of the sulphydryl groups may be described as "full sites reactivity" phenomena. After chemical modification by iodoacetamidonaphtol both processes follow "half of the sites reactivity".

In this report, we describe the isolation of a 50 kDa polypeptide from the detergent-resistant cytomatrix of unfertilized sea urchin egg. This polypeptide shares with the intermediate filaments the property of insolubility in high ionic strength buffer solution. However, it does not cross-react with anti-vimentin and anti-cytokeratin antibodies. Studies performed by indirect immunofluorescence microscopy with an immunospecific serum raised against this polypeptide show that during the first cell cycle the polypeptide exhibits similar configuration changes as those described for tubulin. Using immunocytochemical light and electron microscopy, we present evidence indicating that this 50 kDa polypeptide is a constituent of the isolated mitotic apparatus; it is mainly located on patches of microfibrillar material found close to the microtubules. The 50 kDa polypeptide is not extracted from taxol-assembled microtubules by the 0.6 M NaCl treatment. However, the difference in solubility between this protein and the previously studied microtubule-associated proteins does not preclude the possibility of the 50 kDa polypeptide on being a "microtubule-associated protein". The possible significance of this novel cytoskeletal component is discussed.

This report describes the effects of 10 mM procaine on microtubule assembly and on DNA synthesis, as followed by [3H]colchicine binding assays and [3H]thymidine incorporation respectively, in fertilized Paracentrotus lividus eggs. In the absence of microtubule assembly inhibitors, about 25% of the total egg tubulin is submitted to two cycles of polymerization prior to the first cell division, this polymerization process precedes DNA synthesis. If the zygotes are treated with 10 mM procaine in the course of the cell cycle, tubulin polymerization is inhibited or microtubules are disassembled. DNA synthesis is inhibited when procaine treatment is performed 10 min, before the initiation of the S-period. However, when the drug is applied in the course of this synthetic period, the process is normally accomplished, but the next S-period becomes inhibited. Moreover, procaine treatment increases the cytoplasmic pH of the fertilized eggs by about 0.6 to 0.8 pH units. This pH increase precedes microtubule disassembly and inhibition of DNA synthesis. Washing out the drug induces a decrease of the intracellular pH which returns to about the same value as that of the fertilized egg controls. This pH change is then followed by the reinitiation of microtubule assembly, DNA synthesis and cell division. Our results show that the inhibition of both tubulin polymerization and DNA synthesis in fertilized eggs treated with 10 mM procaine, appears to be related to the drug-induced increase in cytoplasmic pH.

A lateral fronto-ethmoidal approach simultaneously exposing the frontal sinus and the nasal fossae appears to be a necessity for the surgical treatment of fronto-ethmoidal pathology. It is possible to fashion an osteo-plastic flap in the fronto-naso-maxillary region. The technique of the approach is described. The operation leaves no ocular functional sequelae and the scar is minimal. Twenty one operations by fronto-nasal flap approach are described, 10 for benign tumours of the fronto-ethmoidal system and 11 with the aim of re-aerating the frontal sinus for cases of complicated or iatrogenic serious sinusitis. The results are studied. The indications of the fronto-nasal flap are described: In tumour pathology, this technique must be used for osteomas and mucoceles of the fronto-ethmoidal system as soon as the ethmoidal component reaches or goes beyond the middle ethmoid. If the fronto-ethmoidal lesion only involves the anterior ethmoid, it is then accessible via simple frontal flap. Inverted papillomas which require wide exposure should also be treated via this approach. In infectious pathology, the fronto-nasal flap offers the possibility, after eradication of fronto-ethmoidal lesions and calibration of the naso-frontal canal, of re-aeration of the frontal sinus which seems preferable to its exclusion. The possibility of re-aeration of the frontal sinus by an osteo-plastic procedure is progress in comparison with lost bone craniotomy procedures.