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Abstract The clinical presentation of beriberi can be quite varied. In the extreme form, profound cardiovascular involvement leads to circulatory collapse and death. This case report is of a 72 year-old male who was admitted to the Neurology inpatient ward with progressive bilateral lower extremity weakness and parasthesia. He subsequently developed pulmonary edema and high output cardiac failure requiring intubation and blood pressure support. With the constellation of peripheral neuropathy, encephalopathy, ophthalmoplegia, unexplained heart failure, and lactic acidosis, thiamine deficiency was suspected. He was empirically initiated on thiamine replacement therapy and his thiamine level pre-therapy was found to be 23 nmol/L (Normal: 80-150 nmol/L), consistent with the diagnosis of beriberi. Cardiovascular magnetic resonance (CMR) showed severe left ventricular systolic dysfunction, markedly increased myocardial T2, and minimal late gadolinium enhancement (LGE). After 5 days of daily 100 mg IV thiamine and supportive care, the hypotension resolved and the patient was extubated and was released from the hospital 3 weeks later. Our case shows via CMR profound myocardial edema associated with wet beriberi.

It is well known that ceramic materials are highly susceptible to environmental assisted subcritical crack growth. In addition, this subcritical crack growth could be also related to cyclic loading (mechanical fatigue). This type of behaviour is not observed either in glasses nor in traditional ceramics. However this phenomena is clearly active in many advanced ceramics. The aim of this work is to obtain a procedure for detecting the presence of cyclic fatigue in ceramic materials. This procedure attempts to obtain cyclic fatigue life estimations and to compare it with the static loading experimental results. Through this comparisons it is possible to asses whether the cyclic fatigue is acting or not. Finally some calculations are conducted in ceramic materials (alumina, mullite and ZTA) with natural and indentation flaws.Los materiales cerámicos son susceptibles al crecimiento de fisuras por la acción combinada del medio ambiente y la aplicación de carga (fatiga estática). Por otra parte, el crecimiento subcrítico de fisuras en cerámicas también puede ser producido por la aplicación de cargas fluctuantes (fatiga mecánica). Este fenómeno no se observa en vidrios ni en cerámicas monocristalinas, pero si en muchos de los llamados materiales cerámicos avanzados. En este trabajo se describe una metodología utilizada para detectar la presencia de fatiga mecánica en materiales cerámicos, basada en la obtención de estimaciones de la vida a fatiga del material bajo cargas fluctuantes y su comparación con los resultados experimentales bajo carga constante. Este método se ha aplicado a fisuras naturales y de indentación en algunos materiales cerámicos (mullita, alúmina y ZTA).

Adenosine-5-triphosphate (ATP) is the main energy vector in biological systems, thus its regeneration is an important issue for the application of many enzymes of interest in biocatalysis and synthetic biology. We have developed an electroenzymatic ATP regeneration system consisting in a gold electrode modified with a floating phospholipid bilayer that allows coupling the catalytic activity of two membrane-bound enzymes: NiFeSe hydrogenase from Desulfovibrio vulgaris and F 1 F o -ATP synthase from Escherichia coli. Thus, H 2 is used as a fuel for producing ATP. This electro-enzymatic assembly is studied as ATP regeneration system of phosphorylation reactions catalysed by kinases, such as hexokinase and NAD + -kinase for respectively producing glucose-6-phosphate and NADP + ., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

A reversed phase high performance liquid chromatography (RP-HPLC) method was developed for the quantitative determination of recombinant HIV-1 gp145 produced in CHO-K1 cells, as measured directly from culture supernatants. Samples were diluted in 50% D-PBS and 50% PowerCHO-2 (PC2) spent medium, and resolved on a Zorbax 300SB-C8 Rapid Resolution (2.1 × 50 mm, 3.5 µm) column, fitted with a C8 guard column (Zorbax 300SB-C8, 2.1 × 12.5 mm, 5 µm), using 0.1% TFA and 2% n-propanol in LC-MS water as mobile phase A and 0.1% TFA, 70% isopropanol, and 20% acetonitrile in LC-MS water as mobile phase B. The column temperature was 80 °C, the flow rate was 0.4 mL/min and the absorbance was monitored at 280 nm. The procedures and capabilities of the method were evaluated against the criteria for linearity, limit of detection (LOD), accuracy, repeatability, and robustness as defined by the International Conference on Harmonization (ICH) 2005 Q2(R1) guidelines. Two different variants of the HIV-1 envelope protein (Env), CO6980v0c22 gp145 and SF162 gp140, were analyzed and their retention times were found to be different. The method showed good linearity (R 2  = 0.9996), a lower LOD of 2.4 µg/mL, and an average recovery of 101%. The analysis includes measurements of accuracy, inter-user precision, and robustness. Overall, we present a RP-HPLC method that could be applied for the quantitation of cell culture titers for this and other variants of HIV Env following ICH guidelines., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Adenosine triphosphate (ATP) is a key molecule as energy vector for living organisms, therefore its detection reveals the presence of microbial colonies. Environments where the existence of microbial pathogens suppose a health hazard can benefit from real time monitoring of such molecule. We report a potentiometric biosensor based on ATP-synthase from Escherichia coli reconstituted in a floating phospholipid bilayer over gold electrodes modified with a 4-aminothiophenol self-assembled monolayer. The use of a pH-dependent redox probe on the electrode surface allows a simple, specific and reliable on site determination of ATP concentration from 1 μM to 1 mM. The broad range ATP biosensor can offer an alternative way of measuring in a few minutes the presence of microbial contamination., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

FtsZ filaments localize at the middle of the bacterial cell and participate in the formation of a contractile ring responsible for cell division. Previous studies demonstrated that the highly conserved negative charge of glutamate 83 and the positive charge of arginine 85 located in the lateral helix H3 bend of Escherichia coli FtsZ are required for in vivo cell division. In order to understand how these lateral mutations impair the formation of a contractile ring,we extend previous in vitro characterization of these mutants in solution to study their behavior on lipid modified surfaces. We study their interaction with ZipAand look at their reorganization on the surface. We found that the dynamic bundling capacity of the mutant proteins is deficient, and this impairment increases the more the composition and spatial arrangement of the reconstituted system resembles the situation inside the cell: mutant proteins completely fail to reorganize to form higher order aggregates when bound to an E.coli lipid surface through oriented ZipA.We conclude that these surface lateral point mutations affect the dynamic reorganization of FtsZ filaments into bundles on the cell membrane, suggesting that this event is relevant for generating force and completing bacterial division., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Erythrocyte membranes have been particularly useful as a model for studies of membrane structure and mechanics. Native erythroid membranes can be electroformed as giant unilamellar vesicles (eGUVs). In the presence of ATP, the erythroid membrane proteins of eGUVs rearrange into protein networks at the microscale. Here, we present a detailed nanomechanical study of individual protein microfilaments forming the protein networks of eGUVs when spread on supporting surfaces. Using Peak Force tapping Atomic Force Microscopy (PF-AFM) in liquid environment we have obtained the mechanical maps of the composite lipid-protein networks supported on solid surface. In the absence of ATP, the protein pool was characterized by a Young's Modulus E pool ≈5-15MPa whereas the complex filaments were found softer after protein supramolecular rearrangement; E fil ≈0.4MPa. The observed protein softening and reassembling could be relevant for understanding the mechanisms of cytoskeleton reorganization found in pathological erythrocytes or erythrocytes that are affected by biological agents., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

We report a molecular study of the two known patients with autosomal recessive, partial interferon-γ receptor (IFN-γR)2 deficiency (homozygous for mutations R114C and G227R), and three novel, unrelated children, homozygous for S124F (P1) and G141R (P2 and P3). IFN-γR2 levels on the surface of the three latter patients' cells are slightly lower than those on control cells. The patients' cells also display impaired, but not abolished, response to IFN-γ. Moreover, the R114C, S124F, G141R and G227R IFNGR2 hypomorphic alleles all encode misfolded proteins with abnormal N-glycosylation. The mutants are largely retained in the endoplasmic reticulum, although a small proportion reach and function at the cell surface. Strikingly, the IFN-γ response of the patients' cells is enhanced by chemical modifiers of N-glycosylation, as previously shown for patients with gain-of-glysosylation T168N and misfolding 382-387dup null mutations. All four in-frame IFNGR2 hypomorphic mutant alleles encoding surface-expressed receptors are thus deleterious by a mechanism involving abnormal N-glycosylation and misfolding of the IFN-γR2 protein. The diagnosis of partial IFN-γR2 deficiency is clinically useful, as affected patients should be treated with IFN-γ, [corrected] unlike patients with complete IFN-γR2 deficiency. Moreover, inhibitors of glycosylation might be beneficial in patients with complete or partial IFN-γR2 deficiency due to misfolding or gain-of-glycosylation receptors.

Public financing of IVF aims at increasing access to treatment while decreasing the expenses associated with multiple pregnancies. Critics argue that it is associated with lower pregnancy rates. This study compared cycles performed during 2009 (before implementation of Quebec's public IVF programme; period I) to those performed in the year following implementation (period II) in a single IVF centre. First fresh cycles in period I (499 women) and first fresh cycles (815 women) along with their corresponding first vitrified-warmed transfer (271 women) in period II were evaluated. From period I to period II, single-embryo transfer increased from 17.3% to 85.0% (P<0.001), multiple ongoing pregnancy rate decreased from 25.8% to 1.6% (P<0.001) and ongoing pregnancy rate decreased from 31.9% to 23.3% (P=0.001). During period II, the ongoing pregnancy rate per vitrified-warmed embryo transfer was 19.2%, leading to a cumulative ongoing pregnancy rate per initiated cycle of 29.7%, which was not different to the pregnancy rate per fresh cycle during period I (31.9%). To conclude, Quebec's public IVF programme decreased multiple pregnancy rates while maintaining an acceptable cumulative ongoing pregnancy rate, a more precise outcome to evaluate the impact of public IVF programmes., (Copyright © 2013 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

The TodS/TodT two-component system controls the expression of tod genes for toluene degradation in Pseudomonas putida. TodT binds to two pseudopalindromes at -106 (Box-1) and -85 (Box-2), as well as to a half-palindrome (Box-3), with respect to the main transcription initiation site in the PtodX promoter. TodT recognizes each half-palindrome in Boxes-1 and -2, but affinities for these sequences are lower than those for the pseudopalindromes, pointing towards positive cooperativeness in intrabox recognition. TodT's affinity for DNA fragments containing two vicinal boxes (either Boxes-1 and -2 or Boxes-2 and -3) is higher than its affinity for individual boxes, suggesting interbox cooperativeness. Similar patterns of cooperativeness were observed for the recombinant TodT DNA-binding domain [C-terminal TodT fragment (aa 154-206) (C-TodT)], suggesting important cooperativeness determinants in this domain. Occupation of PtodX by TodT is initiated at Box-1, and optimization of its palindromic order increases affinity in vitro; however, this does not result in enhanced in vivo gene expression. Mutations at either half of the Box-1 palindrome have no significant effects on transcriptional activity, whereas mutations in the entire Box-1 cause a 12-fold reduction. Using atomic force microscopy, we show that TodT induces a DNA hairpin bend at PtodX between Boxes-2 and -3, as supported by footprint studies showing a hyperreactive nucleotide at G -68. The N-terminal part of TodT seems to play a central role in hairpin formation, since C-TodT neither induces a bend nor causes G -68 hyperreactivity in footprints. This hairpin seems important for transcriptional activation, since C-TodT binding to PtodX does not stimulate transcription.

Objective: The main aim of this study was to establish the contents of the lay illness models on depression, cancer, hypertension, schizophrenia and influenza in healthy and ill people suffering from these diseases who have/have not coexisted with people with these health alterations., Methods: Dimensions of lay illness models for depression, schizophrenia, cancer, hypertension and influenza were assessed in 348 people (62.6% women) aged 13-50 (M=20.72; S.D.=5.96) with different personal experience with the studied diseases., Results: Lay illness beliefs are usually close to medical knowledge, but in some relevant cases they are very divergent from this. Experience with the disease (to have suffered from it or to have coexisted with an ill relative) seems to have a great influence in the contents of lay illness models., Conclusion: People's representations on illnesses are not complete or correct at all, and this will have, as the Common Sense Model establishes, relevant repercussions on individuals' behaviors in relation to health and illness and on the outcomes of diseases., Practice Implications: To know the personal illness models for physical and mental health threats of healthy and ill people with different personal experience with the disease has important implications for health professionals' promotion and prevention strategies and clinical (treatment/rehabilitation) actuations.

The TtgV repressor belongs to the large but infrequently investigated IclR family of transcriptional regulators. Although members of this family usually exhibit high effector specificity, TtgV possesses multidrug binding properties. The TtgV protein regulates the expression of the ttgGHI operon encoding the main solvent extrusion pump of the extremophile Pseudomonas putida DOT-T1E strain. Here we used a multidisciplinary approach to study the functional oligomeric state of TtgV during repression and derepression events, as well as the molecular basis of TtgV-DNA operator interactions. Analytical ultracentrifugation studies (AUC) show that TtgV is a tetramer in solution and that this oligomeric state does not change in the presence of effectors. We also show that the binding of effectors leads to the dissociation of TtgV as a tetramer from the DNA-TtgV complex. Previous dimethyl sulfate and DNase I footprints revealed that TtgV protected a 42 bp region. Based on AUC, electrophorectic mobility shift assays and isothermal titration calorimetry analyses we show that TtgV recognition specificity is restricted within this operator to a 34-nucleotide stretch and that TtgV may interact with intercalated inverted repeats that share no significant DNA sequence similarities within this short 34-nucleotide segment. Binding stoichiometry is one TtgV tetramer per operator, and affinity for its target DNA is around 200 nM. Circular dichroism analysis reveals that TtgV binding causes DNA distortion and atomic force microscopy imaging of TtgV-DNA operator complexes shows that TtgV induces a 57 degrees convex bend in its operator DNA. We propose that the mechanism of TtgV repression is based on the steric occlusion of the RNA polymerase binding site reinforced by DNA-bending of the ttgV-ttgG promoter region.

Triiodothyronine (T3) exerts most of its effect through nuclear thyroid hormone receptors (TR) which bind mainly as heterodimers with retinoid-X receptors (RXR) to thyroid hormone response elements (TRE) in target genes. It is well known that the synergistic interaction of T3 and glucocorticoids has a role on the synthesis of growth hormone in rat pituitary cell lines and in the T3-induced metamorphosis in amphibians. Glucocorticoids increased mRNAs of T3-regulated hepatic genes. Our laboratory reported increased specific metabolic actions of T3 in rat liver by Dexamethasone (Dex) through a mechanism involving an up-regulation of the maximal binding capacity of TR. In this study we further explored the participation of TR in the molecular mechanism of the Dex-induced increase on liver T3-specific metabolic action. Dex administration to adrenalectomized rats induced an increase of liver TRbeta1 protein and mRNA. Nuclear run-on assay revealed that Dex up-regulated the TR gene transcriptional rate. Transfection assay in COS-7 cells indicated that Dex increased the transcriptional activity of the TRbeta1 promoter. Electrophoretic mobility shift assay demonstrated that Dex induced the binding of additional proteins related to or neighboring the DNA sequence of a glucocorticoid receptor (GR) binding (GRE) half-site in the TRbeta1 promoter. Evidences for an interaction of GR on the TRbeta1 promoter have been obtained. Moreover, the specificity of the GR binding to GRE was determined not only by the GRE DNA sequence, but also by the interaction of the GR with other transacting factors bound to sequences flanking the GRE.

The laser treatment of port-wine stains (PWS) has as a main aim the irreversible damage of ectatic vessels. Blood content of the subcutaneous venous plexus in PWS can be increased by a factor of seven or more, compared to that of the normal skin. The venous blood velocity ranges from 0.1-1 mm/s in capillaries to approximately 22 mm/s in larger vessels of about 300 microns in diameter. A PWS, selected for study, was irradiated with a multiline argon laser 488/515 nm wavelength, 1.5 W power, 200 ms pulse duration, 0.5 mm beam diameter and repetition frequency up to 5 Hz. Laser shots were placed adjacently in an area of 1 cm2. Using these parameters, in the case of dilated PWS vessels with an optical penetration depth and thermal diffusion length less than the diameter of the vessel, together with a transit time of blood across the irradiated spot less than the pulse duration, and estimating that during a pulsed laser emission of 200 ms, the blood has travelled a distance of 3-4 mm, there is a strong indication that hemodynamics during irradiation may influence the pattern of coagulation and agglutination. Thrombosis should occur in the case of small vessels and, in larger vessels, the coagulated blood will only partly fill the lumen. The structure developed in the vessel interior may also change continuously with time, as the coagulated material is progressively replaced by fibrotic tissue and the irregular agglutination pattern may be due to inhomogeneity in the absorbed optical energy.

Scanning tunneling microscopy of metal-coated specimens has become a reliable technique that permits direct three-dimensional visualization of structural details at a level at which individual subunits in protein complexes or even single domains of proteins can be resolved. We describe in this paper a variation of the freeze-drying metal coating procedure that allows us to image with the STM the inner side of the metal replica, previously in contact with the protein molecules. We have tested this new approach with two different well characterized protein systems: freeze-dried two-dimensional crystals of bacteriophage phi 29 connector and the vesicle form of two-dimensional crystals of cytochrome oxidase from beef heart mitochondria. The images obtained have very good contrast and provide direct topographic information of the crystal surface, complementing structural information obtained previously with transmission electron microscopy. The resolution limit is imposed by the size (2-3 nm diameter) and corrugation of the metal grains used to prepare the replica and by the randomness of the metal shadowing.