Patients with multiple sclerosis and low disability display cautious rotational behavior during gait initiation.

Background: Multiple sclerosis induces locomotor impairments. The objective was to characterize the effects of Multiple Sclerosis on whole-body angular momentum control during gait initiation.

Methods: Fifteen patients with Multiple Sclerosis with Expanded Disability status scale of 2.

Influence of aging on the control of the whole-body angular momentum during volitional stepping: An UCM-based analysis.

Evidence suggests that whole-body angular momentum (WBAM) is a highly controlled mechanical variable for performing our daily motor activities safely and efficiently. Recent findings have revealed that, compared to young adults, older adults exhibit larger range of WBAM during various motor tasks, such as walking and stepping. However, it remains unclear whether these age-related changes are ascribed to a poorer control of WBAM with age or not.

Segmental contribution to whole-body angular momentum during stepping in healthy young and old adults.

Recent evidence suggests that during volitional stepping older adults control whole-body angular momentum (H) less effectively than younger adults, which may impose a greater challenge for balance control during this task in the elderly. This study investigated the influence of aging on the segment angular momenta and their contributions to H during stepping. Eighteen old and 15 young healthy adults were instructed to perform a series of stepping at two speed conditions: preferred and as fast as possible.

Effect of increasing speed on whole-body angular momentum during stepping in the elderly.

Recent evidence suggests that older adults may have difficulty controlling whole-body angular momentum (H) during volitional stepping, which could impose a major challenge for balance control and result in potential falls. However, it is not known if and how H is influenced by speed when stepping. This study aimed to investigate the effect on H of increasing speed during step initiation in older adults.

Age-related changes in the control of whole-body angular momentum during stepping.

Background: Appropriate control of whole-body angular momentum (H) is crucial to maintain dynamic balance and thus avoid falling during daily activities. Poor H control ability during locomotion has been found in people with an increased risk of falling, such as post-stroke patients and amputees. In contrast, little is known about the control of H during locomotion in the elderly.

Exploratory study on the possibility to link gasoline samples sharing a common source after alteration by evaporation or combustion.

The source inference of ignitable liquids in forensic science is still a challenging and ongoing research area. In real case applications, specimens of different natures, which may have been exposed to fire or not, may have to be compared. These comparisons are difficult since specimens may have been altered by evaporation, combustion or both.

Evaluation of an untargeted chemometric approach for the source inference of ignitable liquids in forensic science.

Recent research efforts in the domain of fire debris analysis have been mainly oriented towards the development of innovative analytical procedures and chemometric approaches for the detection and classification of ignitable liquids in fire specimens according to the ASTM E1618. However, less attention has been brought to the question of the source inference of ignitable liquids. Infer the identity of source of ignitable liquids recovered from arson sites is still a challenging and ongoing research area.

Influence of gait speed on free vertical moment during walking.

Free vertical moment (FVM) of ground reaction is recognized to be a meaningful indicator of torsional stress on the lower limbs when walking. The purpose of this study was to examine whether and how gait speed influences the FVM when walking. Fourteen young healthy adults performed a series of overground walking trials at three different speeds: low, preferred and fast.

Carbon tetrachloride-mediated lipid peroxidation induces early mitochondrial alterations in mouse liver.

Although carbon tetrachloride (CCl(4))-induced acute and chronic hepatotoxicity have been extensively studied, little is known about the very early in vivo effects of this organic solvent on oxidative stress and mitochondrial function. In this study, mice were treated with CCl(4) (1.5 ml/kg ie 2.

Mitochondrial abnormalities in patients with HIV-HCV co-infection as compared to patients with HCV mono-infection.

Introduction: Mitochondrial dysfunction is a classic complication of HIV infection and its treatment and has also been reported in hepatitis C virus (HCV)-infected patients. Little is known about interactions between both viruses on mitochondrial metabolism.

Methods: We performed a cross-sectional study of HCV-infected patients who underwent liver biopsy as part of their routine care.

Anderson's disease (chylomicron retention disease): a new mutation in the SARA2 gene associated with muscular and cardiac abnormalities.

Anderson's disease (AD) or chylomicron retention disease (CMRD) is a rare hereditary lipid malabsorption syndrome linked to SARA2 gene mutations. We report in this study a novel mutation in two sisters for which the Sar1b protein is predicted to be truncated by 32 amino acids at its carboxyl-terminus. Because the SARA2 gene is also expressed in the muscle, heart, liver and placenta, extraintestinal clinical manifestations may exist.

Fluoroartemisinins: metabolically more stable antimalarial artemisinin derivatives.

This report is an overview on the design, preparation, and evaluation of metabolically stable artemisinins, using fluorine substitution. The chemical challenges encountered for the incorporation of fluorine-containing elements and the preparation of a large range of 10-trifluoromethyl artemisinin derivatives are detailed. Impact of the fluorine substitution on the antimalarial activity is also highlighted.

Synthesis of new artemisinin-derived dimers by self-cross-metathesis reaction.

[reaction: see text] New artemisinin-derived dimers, fluorinated or not, have been prepared by a self-cross metathesis reaction in the presence of first- or second-generation ruthenium catalysts without degradation of the endoperoxide bridge and with a good E/Z selectivity (up to 100:0).

Identifying inaccuracies on emergency medicine residency applications.

Background: Previous trials have showed a 10-30% rate of inaccuracies on applications to individual residency programs. No studies have attempted to corroborate this on a national level. Attempts by residency programs to diminish the frequency of inaccuracies on applications have not been reported.

The chemistry of trifluoromethyl imines and related acetals derived from fluoral.

Trifluoromethylated nitrogen-containing molecules have been shown to have important biological effects and their synthesis is in the focus of the pharmaceutical industry. In the last few years, simple nitrogen derivatives of fluoral, i.e.

Delaying shock for cardiopulmonary resuscitation: does it save lives?

Purpose Of Review: Out-of-hospital cardiac arrest claims more than 450,000 lives annually in North America. Many communities have dedicated significant resources to provide rapid defibrillator response for patients in ventricular fibrillation. In spite of these efforts, mortality from out-of-hospital cardiac arrest has not improved significantly.

Analogues of key precursors of aspartyl protease inhibitors: synthesis of trifluoromethyl amino epoxides.

The synthesis of the title compound is described through original and tailored synthetic protocols. The addition of vinylmagnesium bromide to CF(3)-N-aryl and N-alkyl aldimines was efficient and did not require an activating N-substituent. The resultant CF3-allylamines were converted in an efficient and completely stereoselective route to syn CF3-epoxides 3 via formation of bromhydrins 8.

Mitochondrial abnormalities in HIV-infected lipoatrophic patients treated with antiretroviral agents.

Background: Lipodystrophy is now widely described in HIV infected patients under antiretroviral regimen with important psychological impact. But physiopathology of loss of fat mass is still debated and the role of mitochondrial impairment is not clearly defined.

Objective: To correlate clinical lipoatrophy (LA) in HIV patients with long-term treatment by nucleoside reverse transcriptase inhibitors (NRTIs) and muscular impairment related to mitochondrial dysfunction.

Fluoroartemisinin: trifluoromethyl analogues of artemether and artesunate.

The synthesis of a series of C-10 trifluoromethyl ethers of artemisinin has been achieved from key bromide 8, itself carried out in two steps from artemisinin. The substitution of 8 with methanol, ethanol, or succinic acid allowed the access of C-10 CF(3) analogues of beta-artemether, beta-arteether, or artesunate, respectively, in good yields (up to 89%). The presence of the CF(3) group at C-10 of artemisinin clearly increased the chemical stability under simulated stomach acid conditions.

Orally active antimalarials: hydrolytically stable derivatives of 10-trifluoromethyl anhydrodihydroartemisinin.

New fluoroartemisinin derivatives containing polar or water-soluble functionalities at C-16 (11a-j, 12a-g) were synthesized using the key intermediate 16-bromo-10-trifluoromethyl anhydrodihydroartemisinin 10. The substitution reaction from 10 was more selective than that from the nonfluorinated parent bromide; the allylic bromide 10 underwent no allylic rearrangement and provided only nucleophilic substitution products in high yields with N-, O-, and C-nucleophiles. Among them, amines 11a-c appeared to be highly in vivo efficient antimalarials on mice infected with Plasmodium berghei, more than the reference sodium artesunate 1d.

Preparation of 10-trifluoromethyl artemether and artesunate. Influence of hexafluoropropan-2-ol on substitution reaction.

To prepare 10-trifluoromethyl analogues of important antimalarials such as artemether and artesunate, the substitution reaction of the 10-trifluoromethyl hemiketal 6 and bromide 4 derived from artemisinin was investigated. While 6 appeared to be unreactive under various conditions, bromide 4 could easily undergo substitution with methanol under electrophilic assistance or noncatalyzed conditions. Optimization of the reaction revealed the role of CH(2)Cl(2) as solvent to avoid the competitive elimination process and the crucial influence of hexafluoro-2-propanol (HFIP) in increasing the rate and the stereoselectivity of the substitution reaction (de >98%).

Stereoselective Barbier-type allylation reaction of trifluoromethyl aldimines.

Trifluoromethyl aldimines could react, under Barbier conditions in the presence of activated zinc, in DMF at room temperature or in THF at reflux, with various allyl bromides to provide the corresponding homoallylamines. Secondary homoallyl trifluoromethylamines were stereoselectively obtained from the optically active aldimine 12 with an excellent diastereoisomeric excess (98%).

Alkylation of manganese(II) tetraphenylporphyrin by antimalarial fluorinated artemisinin derivatives.

The alkylating properties of two artemisinin derivatives bearing a trifluoromethyl substituent at C10 were evaluated toward manganese(II) tetraphenylporphyrin, considered as a heme model. Chlorin-type covalent adducts were obtained by alkylation of the porphyrin ring by C-centered radicals derived from reductive activation of the peroxide function of the drugs.