436 research outputs found
Olivier Roy, La Nouvelle Asie centrale ou la fabrication des nations
Le titre du livre, La Nouvelle Asie centrale ou la fabrication des nations, ne reflète pas parfaitement son contenu. L'ouvrage se concentre sur l'évolution de la fabrication des nations en Asie centrale depuis le Moyen Âge jusqu'à présent, et non pas sur la nouvelle Asie centrale. L'analyse des données historiques est en effet indispensable à la compréhension de la fabrication des nations. Le lecteur aurait cependant aimé que la situation actuelle soit plus développée qu'elle ne l'est. En dépit de ces réserves, La Nouvelle Asie centrale ou la fabrication des nations est une contribution de qualité aux études centre-asiatiques et à l'analyse de la formation des identités nationales
Fluorescent D-amino-acids reveal bi-cellular cell wall modifications important for Bdellovibrio bacteriovorous predation
Modification of essential bacterial peptidoglycan (PG) containing cell walls can lead to antibiotic resistance, for example β-lactam resistance by L,D-transpeptidase activities. Predatory Bdellovibrio bacteriovorus are naturally antibacterial and combat infections by traversing, modifying and finally destroying walls of Gram-negative prey bacteria, modifying their own PG as they grow inside prey. Historically, these multi-enzymatic processes on two similar PG walls have proved challenging to elucidate. Here, with a PG labelling approach utilizing timed pulses of multiple fluorescent D-amino acids (FDAAs), we illuminate dynamic changes that predator and prey walls go through during the different phases of bacteria:bacteria invasion. We show formation of a reinforced circular port-hole in the prey wall; L,D-transpeptidaseBd mediated D-amino acid modifications strengthening prey PG during Bdellovibrio invasion and a zonal mode of predator-elongation. This process is followed by unconventional, multi-point and synchronous septation of the intracellular Bdellovibrio, accommodating odd- and even-numbered progeny formation by non-binary division
Localization of Dirac-like excitations in graphene in the presence of smooth inhomogeneous magnetic fields
The present article discusses magnetic confinement of the Dirac excitations
in graphene in presence of inhomogeneous magnetic fields. In the first case a
magnetic field directed along the z axis whose magnitude is proportional to
is chosen. In the next case we choose a more realistic magnetic field
which does not blow up at the origin and gradually fades away from the origin.
The magnetic fields chosen do not have any finite/infinite discontinuity for
finite values of the radial coordinate. The novelty of the two magnetic fields
is related to the equations which are used to find the excited spectra of the
excitations. It turns out that the bound state solutions of the two-dimensional
hydrogen atom problem are related to the spectra of graphene excitations in
presence of the (inverse-radial) magnetic field. For the other magnetic
field profile one can use the knowledge of the bound state spectrum of a
two-dimensional cut-off Coulomb potential to dictate the excitation spectra of
the states of graphene. The spectrum of the graphene excitations in presence of
the inverse-radial magnetic field can be exactly solved while the other case
cannot be. In the later case we give the localized solutions of the zero-energy
states in graphene.Comment: 9 pages, 6 figures, to appear in Journal of Physics: Condensed Matte
Low-cost liquid medium for in vitro cultivation of Leishmania parasites in low-income countries
Background: Cutaneous Leishmaniasis (CL) induced by Leishmania aethiopica
has two clinical manifestations: ulcerating, self-healing CL and
non-ulcerating, non-healing CL. The grossly disfiguring multiple nodules
on the face and exterior surface of limbs during non-ulcerative CL are
sometimes misdiagnosed as other skin infections. Thus the need for
definitive and prompt laboratory diagnosis will be required. Identifying
Leishmania parasite by culture method is considered as a definitive
method for initiation of treatment and as an effective component of
leishmaniasis control methods. Recently the involvement of Fas (CD95)
and Tumor Necrosis Factor (TNF) Related Apoptosis Inducing Ligand (TRAIL)
induced apoptotic pathways were proposed to be involved in tissue
destruction and ulceration during L. major induced CL.
Aims: 1) to develop an alternative culture media that could minimize the
cost for culturing Leishmania from patient lesions.
2) to investigate if the expression of FasL and TRAIL differs in
ulcerating and non- ulcerative CL.
Methods: GALF-1 media was formulated in our lab and compared to RPMI 1640
medium and conventional Locke s semi solid media (LSSM) which is one of
the modifications of Novy-MacNeal-Nicolle (NNN) culture media.
Amastigotes transformation, cryopreservation, recovery of parasites, cost
and mass cultivation were analysed. Expression of Fas ligand (FasL),
TRAIL and apoptosis were assessed by immunohistology in human skin
biopsies from L. aethiopica induced ulcerative or non-ulcerative CL. FasL
and TRAIL blocking experiments were performed in a murine model of CL.
Results and discussion: GALF-1 is cheap and its ingredients available in
a low income country such as Ethiopia. GALF-1 was able to transform
amastigotes from Ethiopian patients samples and could be used to
cultivate promastigotes in large quantities. Cost analysis showed 80% to
95 % decreased costs as compared to conventional media. Promastigotes
cultured with GALF-1 could be cryopreserved in liquid nitrogen with
comparable re-culture potential to conventional media. Affordability of
diagnostic assays is a key issue for resource poor countries and the
possibility to cut the cost of the efficient culture method for diagnosis
through the use of inexpensive local formulated reagents could improve
the diagnosis of leishmaniasis in low income endemic countries.
More FasL expressing cells were detected in dermis of ulcerative CL as
compared to non-ulcerative CL and controls. TRAIL expression was higher
in ulcerative CL as compared to non-ulcerative CL and controls in both
epidermis and dermis. Increased dermal expression of FasL and TRAIL was
associated with ulcer formation during CL. This correlated with an
inhibition of the ulcerative process in a murine CL model during FasL and
TRAIL neutralisation.The mechanisms of the involvement of FasL and TRAIL
in ulceration was not elucidated and putative reason(s) for the
difference in dysregulation of apoptosis are discussed
Physiotherapy scoliosis-specific exercises: a comprehensive review of seven major schools
In recent decades, there has been a call for change among all stakeholders involved in scoliosis management. Parents of children with scoliosis have complained about the so-called “wait and see” approach that far too many doctors use when evaluating children’s scoliosis curves between 10° and 25°. Observation, Physiotherapy Scoliosis Specific Exercises (PSSE) and bracing for idiopathic scoliosis during growth are all therapeutic interventions accepted by the 2011 International Society on Scoliosis Orthopaedic and Rehabilitation Treatment (SOSORT). The standard features of these interventions are: 1) 3-dimension self-correction; 2) Training activities of daily living (ADL); and 3) Stabilization of the corrected posture. PSSE is part of a scoliosis care model that includes scoliosis specific education, scoliosis specific physical therapy exercises, observation or surveillance, psychological support and intervention, bracing and surgery. The model is oriented to the patient. Diagnosis and patient evaluation is essential in this model looking at a patient-oriented decision according to clinical experience, scientific evidence and patient’s preference. Thus, specific exercises are not considered as an alternative to bracing or surgery but as a therapeutic intervention, which can be used alone or in combination with bracing or surgery according to individual indication. In the PSSE model it is recommended that the physical therapist work as part of a multidisciplinary team including the orthopeadic doctor, the orthotist, and the mental health care provider - all are according to the SOSORT guidelines and Scoliosis Research Society (SRS) philosophy. From clinical experiences, PSSE can temporarily stabilize progressive scoliosis curves during the secondary period of progression, more than a year after passing the peak of growth. In non-progressive scoliosis, the regular practice of PSSE could produce a temporary and significant reduction of the Cobb angle. PSSE can also produce benefits in subjects with scoliosis other than reducing the Cobb angle, like improving back asymmetry, based on 3D self-correction and stabilization of a stable 3D corrected posture, as well as the secondary muscle imbalance and related pain. In more severe cases of thoracic scoliosis, it can also improve breathing function. This paper will discuss in detail seven major scoliosis schools and their approaches to PSSE, including their bracing techniques and scientific evidence. The aim of this paper is to understand and learn about the different international treatment methods so that physical therapists can incorporate the best from each into their own practices, and in that way attempt to improve the conservative management of patients with idiopathic scoliosis. These schools are presented in the historical order in which they were developed. They include the Lyon approach from France, the Katharina Schroth Asklepios approach from Germany, the Scientific Exercise Approach to Scoliosis (SEAS) from Italy, the Barcelona Scoliosis Physical Therapy School approach (BSPTS) from Spain, the Dobomed approach from Poland, the Side Shift approach from the United Kingdom, and the Functional Individual Therapy of Scoliosis approach (FITS) from Poland
A Major Role for Perifornical Orexin Neurons in the Control of Glucose Metabolism in Rats
OBJECTIVE-The hypothalamic neuropeptide orexin influences (feeding) behavior as well as energy metabolism. Administration of exogenous orexin-A into the brain has been shown to increase both food intake and blood glucose levels. In the present study, we investigated the role of endogenous hypothalamic orexin release in glucose homeostasis in rats. RESEARCH DESIGN AND METHODS-We investigated the effects of the hypothalamic orexin system on basal endogenous glucose production (EGP) as well as on hepatic and peripheral insulin sensitivity by changing orexinergic activity in the hypothalamus combined with hepatic sympathetic or parasympathetic denervation, two-step hyperinsulinemic-euglycemic clamps, immunohistochemistry, and RT-PCR studies. RESULTS-Hypothalamic disinhibition of neuronal activity by the gamma-aminobutyric acid receptor antagonist bicuculline (BIC) increased basal EGP, especially when BIC was administered in the perifornical area where orexin-containing neurons but not melanocortin-concentrating hormone-containing neurons were activated. The increased BIC-induced EGP was largely prevented by intracerebroventricular pretreatment with the orexin-1 receptor antagonist. Intracerebroventricular administration of orexin-A itself caused an increase in plasma glucose and prevented the daytime decrease of EGP. The stimulatory effect of intracerebroventricular orexin-A on EGP was prevented by hepatic sympathetic denervation. Plasma insulin clamped at two or six times the basal levels did not counteract the stimulatory effect of perifornical BIC on EGP, indicating hepatic insulin resistance. RT-PCR showed that stimulation of orexin neurons increased the expression of hepatic glucoregulatory enzymes. CONCLUSIONS-Hypothalamic orexin plays an important role in EGP, most likely by changing the hypothalamic output to the autonomic nervous system. Disturbance of this pathway may result in unbalanced glucose homeostasis. Diabetes 58:1998-2005, 200
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