44 research outputs found
Microwave, infrared and Raman spectra, r0 structural parameters, ab initio calculations and vibrational assignment of 1-fluoro-1-silacyclopentanea)
The microwave spectrum (6500–18 500 MHz) of 1-fluoro-1-silacyclopentane, c-C4H8SiHF has been recorded and 87 transitions for the 28Si, 29Si, 30Si, and 13C isotopomers have been assigned for a single conformer. Infrared spectra (3050-350 cm−1) of the gas and solid and Raman spectrum (3100-40 cm−1) of the liquid have also been recorded. The vibrational data indicate the presence of a single conformer with no symmetry which is consistent with the twist form. Ab initio calculations with a variety of basis sets up to MP2(full)/aug-cc-pVTZ predict the envelope-axial and envelope-equatorial conformers to be saddle points with nearly the same energies but much lower energy than the planar conformer. By utilizing the microwaverotational constants for seven isotopomers (28Si, 29Si, 30Si, and four 13C) combined with the structural parameters predicted from the MP2(full)/6–311+G(d,p) calculations, adjusted r0 structural parameters have been obtained for the twist conformer. The heavy atom distances in Å are: r0(SiC2) = 1.875(3); r0(SiC3) = 1.872(3); r0(C2C4) = 1.549(3); r0(C3C5) = 1.547(3); r0(C4C5) = 1.542(3); r0(SiF) = 1.598(3) and the angles in degrees are: ∠CSiC = 96.7(5); ∠SiC2C4 = 103.6(5); ∠SiC3C5 = 102.9(5); ∠C2C4C5 = 108.4(5); ∠C3C5C4 = 108.1(5); ∠F6Si1C2 = 110.7(5); ∠F6Si1C3 = 111.6(5). The heavy atom ring parameters are compared to the corresponding rs parameters. Normal coordinate calculations with scaled force constants from MP2(full)/6–31G(d) calculations were carried out to predict the fundamental vibrational frequencies, infrared intensities, Raman activities, depolarization values, and infrared band contours. These experimental and theoretical results are compared to the corresponding quantities of some other five-membered rings
Can microcredit help improve the health of poor women? Some findings from a cross-sectional study in Kerala, India
Deep brain stimulation for Parkinson's disease
Abstract Dopaminerigic replacement therapy with levodopa/carbidopa is still the cornerstone for the treatment of Parkinson's disease (PD). However, the medical management of PD is complicated by the appearance of disabling motor response fluctuations, levodopa-induced dyskinesias and psychosis. Since the early 1990s, surgical therapies have made a rapid reentry into the therapeutic armamentarium for PD and deep brain stimulation (DBS) of the globus pallidus interna or subthalamic nuclei is currently the most promising of such interventions. Recognition of the physiological changes in basal ganglia circuits in animal models of PD has provided the much-needed theoretic basis for targeting these areas. DBS of these areas has proven to be a safe procedure and effective against all the major motor symptoms of PD. Though not curative it can substantially reduce motor response fluctuations, levodopa-induced dyskinesias, and improve the quality of life of these patients. DBS is an expensive treatment and hardware-related complications are not rare. The results of the procedure are dependent on careful patient selection and the experience of the performing team. An update on the principles, methods and results of such procedures is essential to raise the awarenes of this new therapeutic modality and to provide guidelines to the referring physicians
Review Article - Botulinum toxins: Pharmacology and its current therapeutic evidence for use
Botulinum toxins are, as a group, among the most potent neuromuscular
toxins known, yet they are clinically useful in the management of
conditions associated with muscular and glandular over-activity.
Botulinum toxins act by preventing release of acetylcholine into the
neuromuscular junction. While botulinum toxin type A is commonly
available, different manufacturers produce specific products, which are
not directly interchangeable and should not be considered as
generically equivalent formulations. Type B is also available in the
market. Each formulation of botulinum toxin is unique with distinct
dosing, efficacy and safety profiles for each use to which it is
applied. Botulinum toxin type A is the treatment of choice based on its
depth of evidence in dystonias and most other conditions. Botulinum
toxin type A is established as useful in the management of spasticity,
tremors, headache prophylaxis and several other neurological
conditions. Active research is underway to determine the parameters for
which the type B toxin can be used in these conditions, as covered in
this review. Botulinum toxin use has spread to several fields of
medicine
Deep brain stimulation for Parkinson's disease
Dopaminerigic replacement therapy with levodopa/carbidopa is still the
cornerstone for the treatment of Parkinson's disease (PD). However, the
medical management of PD is complicated by the appearance of disabling
motor response fluctuations, levodopa-induced dyskinesias and
psychosis. Since the early 1990s, surgical therapies have made a rapid
reentry into the therapeutic armamentarium for PD and deep brain
stimulation (DBS) of the globus pallidus interna or subthalamic nuclei
is currently the most promising of such interventions. Recognition of
the physiological changes in basal ganglia circuits in animal models of
PD has provided the much-needed theoretic basis for targeting these
areas. DBS of these areas has proven to be a safe procedure and
effective against all the major motor symptoms of PD. Though not
curative it can substantially reduce motor response fluctuations,
levodopa-induced dyskinesias, and improve the quality of life of these
patients. DBS is an expensive treatment and hardware-related
complications are not rare. The results of the procedure are dependent
on careful patient selection and the experience of the performing team.
An update on the principles, methods and results of such procedures is
essential to raise the awareness of this new therapeutic modality and
to provide guidelines to the referring physicians
Massive Spontaneous Hemothorax, Giant Intrathoracic Meningocele, and Kyphoscoliosis in Neurofibromatosis Type 1
Neurofibromatosis type 1 (NF‑1) is a heterogeneous autosomal dominant disease with an incidence ranging from 1 in 2500 to 1 in 3000. Rare intrathoracic vascular disorders resulting in massive spontaneous hemothorax with fatal consequences may occur in these patients, so also are various types of skeletal dysplasia which may result in dramatic presentations, posing management challenges to the attending physicians. We report the case of a 43‑year‑old woman with NF‑1 who developed spontaneous massive hemothorax and was discovered to have a concurrent giant intrathoracic meningocele and thoracic kyphoscoliosis with severe vertebral dysplastic changes. Surgical treatment via a right thoracotomy with primary repair of the meningocele and spinal fusion with fibula graft resulted in good outcome. This case represents an extreme manifestation of this otherwise indolent disease in clinical practice.Keywords: Hemothorax, kyphoscoliosis, meningocele, spinal fusio
Review Article - Botulinum toxins: Pharmacology and its current therapeutic evidence for use
Botulinum toxins are, as a group, among the most potent neuromuscular
toxins known, yet they are clinically useful in the management of
conditions associated with muscular and glandular over-activity.
Botulinum toxins act by preventing release of acetylcholine into the
neuromuscular junction. While botulinum toxin type A is commonly
available, different manufacturers produce specific products, which are
not directly interchangeable and should not be considered as
generically equivalent formulations. Type B is also available in the
market. Each formulation of botulinum toxin is unique with distinct
dosing, efficacy and safety profiles for each use to which it is
applied. Botulinum toxin type A is the treatment of choice based on its
depth of evidence in dystonias and most other conditions. Botulinum
toxin type A is established as useful in the management of spasticity,
tremors, headache prophylaxis and several other neurological
conditions. Active research is underway to determine the parameters for
which the type B toxin can be used in these conditions, as covered in
this review. Botulinum toxin use has spread to several fields of
medicine