The effects of conformation and intermolecular hydrogen bonding on the structure and IR spectra of flutamide; a study based on the matrix isolation technique, ab initio and DFT calculations.

In this study, stable conformers of flutamide referred to as an anticancer drug were searched through a relaxed potential energy surface scan carried out at the B3LYP/6-31G(d) level of theory. This was followed by geometry optimization and thermochemistry calculations performed with the HF-SCF, MP2, B3LYP methods and the 6-31G(d), 6-311++G(d,p), aug-cc-pvTZ basis sets for each of the determined minimum energy conformers. The results revealed that flutamide has at least five stable conformers and two of them provide the major contribution to the observed matrix isolation infrared (IR) spectra of the molecule. The effects of conformational variety and intermolecular hydrogen bonding interactions on the observed IR spectra of flutamide were interpreted in the light of the vibrational spectral data obtained for the most stable monomer and dimer forms of the molecule at the same levels of theory. Pulay's "Scaled Quantum Mechanical-Force Field (SQM-FF)" method was used in the refinement of the calculated harmonic wavenumbers, IR intensities and potential energy distributions. This scaling method which proved its superiority to both anharmonic frequency calculations and other scaling methods helped us to correctly interpret the remarkable differences between the matrix IR spectra of flutamide in argon and the condensed phase IR spectra of the molecule in solvents such as KBr, H2O, D2O, ethanol and methanol.

Effect of implantable cardioverter defibrillator implantation on frontal QRS-T angle.

OBJECTIVE: The frontal plane QRS-T [f(QRS-T)] angle refers to the mean difference between the depolarization and repolarization vectors and can easily be measured by digital electrocardiography (ECG). Pacemaker leads can cause fibrosis of the myocardium adjacent to the electrode-tissue interface. We aimed to evaluate whether a right ventricular implantable cardioverter-defibrillator (ICD) lead modifies the f(QRS-T) angle in patients with systolic heart failure (HF). PATIENTS AND METHODS: We prospectively analyzed 101 systolic HF patients who underwent single-lead ICD implantation. The f(QRS) angle before and after ICD implantation was compared with the Wilcoxon signed-rank test. RESULTS: No significant difference in the f(QRS-T) angle was observed before and 6 months after ICD implantation (89.5° ± 97.8° vs. 93.0° ± 90.3°, p=0.211). CONCLUSIONS: Histopathological studies showed that the irritating effect of ICD leads may cause fibrosis and scar tissue. However, we found that fibrosis and scar tissue did not affect the f(QRS-T) angle, which suggests that these pathologies may not have clinical significance. Further studies on the f(QRS-T) angle are warranted to understand its clinical significance in ICD-induced local fibrosis.

An investigation on the structure and group vibrations of balenine molecule by matrix isolation IR spectroscopy, DFT and MP2 based calculations.

Stable conformers of neutral balenine were scanned through molecular dynamics simulations and energy minimizations using Allinger's MM2 force field. For each of the found minimum-energy conformers, geometry optimization and thermochemistry calculations were performed by using B3LYP, MP2, G3MP2B3 methods, 6-31G(d), 6-311++G(d,p) and aug-cc-pvTZ basis sets. The calculation results have indicated that balenine has about twenty stable conformers whose relative energies are in the range of 0-9.5 kcal/mol. Three of these are thought to provide the major contribution to matrix isolation IR spectra of the molecule. Our solvent calculations using the polarized continuum model revealed the stable zwitterion structures which are predicted to dominate IR spectra of balenine in water and heavy water (D2O) solvents. Pulay's SQM-FF method was used in scaling of the harmonic force constants and vibrational spectral data calculated for the neutral and zwitterion structures. These refined calculation data together with those obtained from anharmonic frequency calculations enabled us to correctly interpret the matrix isolation IR spectrum of balenine and the tautomerism-based changes observed in its KBr IR and solution (D2O) IR spectra. The results revealed the crucial role of conformation and zwitterionic tautomerism on the structure and vibrational spectral data of the molecule.

A vibrational spectroscopy study on anserine and its aqueous solutions.

In this study based on vibrational spectroscopic measurements and Density Functional Theory (DFT), we aimed for a reliable interpretation of the IR and Raman spectra recorded for anserine in the solid phase and water (H2O) and heavy water (D2O) solutions. Initial DFT calculations at the B3LYP/6-31G(d) searched possible conformers of the anserine zwitterion using a systematic conformational search. The corresponding equilibrium geometrical parameters and vibrational spectral data were determined for each of the stable conformers (in water) by the geometry optimization and hessian calculations performed at the same level of theory using the polarized continuum model (PCM). The same calculations were repeated to determine the most energetically preferred dimer structure for the molecule and the associated geometry, force field and vibrational spectral data. The harmonic force constants obtained from these calculations were scaled by the Scaled Quantum Mechanical Force Field (SQM) method and then used in the calculation of the refined wavenumbers, potential energy distributions, IR and Raman intensities. These refined theoretical data, which confirm the zwitterion structure for anserine in the solid phase or aqueous solvents, revealed the remarkable effects of intermolecular hydrogen bonding on the structural properties and observed IR and Raman spectra of this molecule.

Effects of high fat diet induced obesity on peripheral nerve regeneration and levels of GAP 43 and TGF-ß in rats.

The increasing frequency of obesity is important because of its accompanying related health problems. The effects of obesity on peripheral nerves have not been elucidated. We investigated the effects of obesity on sciatic nerve regeneration using electrophysiology, stereology, immunohistochemistry, histopathology and functional tests. We used control, obese, control injured and obese injured groups of rats. Electrophysiological results showed that nerve conduction velocity and EMG were same in the experimental groups, but the amplitude of the compound action potential of the control group was significantly higher than that of the obese group. Examination of the nerves showed that the control and obese groups had both larger axon diameters and thicker myelin sheaths. The number of myelinated axons was decreased in both of the injured groups. Axon diameters and myelin sheath thicknesses of the control injured group were significantly greater those of the obese injured group. There were no significant differences in functional tests among the groups. Although growth associated protein 43 immunostaining in the control injured group was significantly greater than that of the obese injured group, no significant difference was observed between the control and obese groups. There was no significant difference in immunohistochemical staining for transforming growth factor beta 3 between the control injured and obese injured groups. Our results suggest that obesity may affect peripheral nerve regeneration negatively after crush injury.

Raman micro-spectroscopic analysis of cultured HCT116 colon cancer cells in the presence of roscovitine.

Raman micro-spectroscopic analysis of cultured HCT116 colon cancer cells in the presence of roscovitine, [seliciclib, 2-(1-ethyl-2-hydroxy-ethylamino)-6-benzylamino-9-isopropylpurine], a promising drug candidate in cancer therapy, has been performed for the first time. The aim of this study was to investigate modulations in colon cancer cells induced by roscovitine. Raman spectra of the cultured HCT116 colon cancer cells treated with roscovitine at different concentrations (0, 5, 10, 25 and 50 µM) were recorded in the range 400-1850 cm(-1). It was shown that the second derivative profile of the experimental spectrum gives valuable information about the wavenumbers and band widths of the vibrational modes of cell components, and it eliminates the appearance of false peaks arising from incorrect baseline corrections. In samples containing roscovitine, significant spectral changes were observed in the intensities of characteristic protein and DNA bands, which indicate roscovitine-induced apoptosis. Roscovitine-induced apoptosis was also assessed by flow cytometry analysis, and analysis of propidium iodide staining. We observed some modifications in amide I and III bands, which arise from alterations in the secondary structure of cell proteins caused by the presence of roscovitine.

Development of entrapment neuropathies in acute stroke patients.

BACKGROUND: Stroke is the third most common cause of mortality and is one of the most common causes of morbidity in the world. Polyneuropathies and entrapment neuropathies are known as the complications of stroke. AIMS OF THE STUDY: In this study we aimed to evaluate the development of entrapment neuropathies in severe stroke patients within the first month of the event. METHODS: Twenty first-ever stroke patients were included in the study. The nerve conduction studies were performed within the first 48 h and repeated 1 month later. RESULTS: At the end of the first month, seven of the 20 patients had median nerve entrapment at the wrist, five had ulnar nerve entrapment at the elbow and seven had peroneal nerve entrapment at the fibular head in the hemiparetic side. Three patients had median nerve entrapment at the wrist, one patient had ulnar nerve entrapment at the elbow, and none had peroneal nerve entrapment in the non-paretic side. CONCLUSION: Our results confirm that, in severe hemiparetic patients, the entrapment neuropathies may be commonly seen, especially in the paretic extremities. The early rehabilitation programs against the development of entrapment neuropathies may be beneficial in stroke patients.

Changing cerebral blood flow velocity detected by transcranial Doppler ultrasound during head up tilt in patients with multiple sclerosis.

BACKGROUND AND PURPOSE: Multiple sclerosis (MS) is a chronic inflammatory disease of central nervous system. We aimed to investigate the cerebral blood flow velocity (CBFV) changes in MS by transcranial Doppler. METHODS: Twenty patients with MS, 20 age-matched healthy controls were included in the study. In both groups, blood flow velocities (BFVs) of middle cerebral arteries (MCAs) were evaluated. The changes of blood pressure, heart rate along with the changes in BFV of MCA were recorded after the patients were raised to upright position. RESULTS: In both groups, upon raising the tilt table to the upright position, the mean CBFV values were found to be lower in comparison with the recorded baseline values (P values <0.05). The decline in the mean CBFV values was more significant in patients with MS (P = 0.01). CONCLUSION: Our study showed upon raise of the tilt table, the mean BFVs decreased more in MS patients than control group with a more prominent change in the subgroup of MS patients with expanded disability scale scores > or =2. By use of transcranial Doppler ultrasound, it may be possible to evaluate BFV changes in patients with MS.

Carpal tunnel syndrome and metabolic syndrome.

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. Many factors such as diabetes mellitus, hypothyroidism, hormonal replacement therapy, corticosteroid use, rheumatoid arthritis and wrist fractures may cause CTS. Metabolic syndrome includes abdominal obesity, dyslipidemia, hyperglycemia, and hypertension that may cause CTS. In this study, we aimed to evaluate the relation between CTS and metabolic syndrome. We studied 107 (96 female and 11 male) right-handed patients who had a clinical and electrophysiologically confirmed diagnosis of CTS. We then divided the patients into two groups (patients with and without metabolic syndrome) according to the criteria of ATP III definition. Eighty (75%) of the patients with CTS had metabolic syndrome. Among the 80 patients with metabolic syndrome, CTS was found in 150 hands (43 mild, 58 moderate and 49 severe cases). Among the 27 patients without metabolic syndrome, CTS was found in 43 hands (27 mild, 14 moderate and 2 severe cases). The electrophysiological parameters (median nerve distal motor latency, median nerve motor amplitude, median nerve motor conduction velocity, median nerve sensory onset latency, median nerve sensory amplitude and median nerve sensory conduction velocity) were worse in patients with metabolic syndrome (P < 0.05). In conclusion, metabolic syndrome was found to be three times more common in patients with CTS and CTS was more severe in patients with metabolic syndrome when compared with those without metabolic syndrome.

Brachial plexus injury during open heart surgery--controlled prospective study.

BACKGROUND: Postoperative brachial plexus injury is often reported because the brachial plexus is stretched by sternotomy and the use of sternal retractors during open heart surgery. In many studies, brachial plexus injuries have been demonstrated by postoperative electrophysiological studies in susceptible patients. In this study, we estimated the incidence, severity, and type of brachial plexus injuries by routine preoperative and postoperative electrophysiological studies of patients undergoing open heart surgery. METHODS: Patients undergoing coronary artery bypass grafting (CABG) surgery (Group 1), heart valve surgery (Group 2), or peripheral vascular surgery (Group 3) were included in the investigation. Electrophysiological studies of both upper extremities were performed five days before and three weeks after the operation. RESULTS: Peripheral nerve problems were found preoperatively in 23 of the 112 patients (21 %). These problems persisted, but similar findings were obtained postoperatively from the left upper extremities of six of the 42 CABG (14 %) and two of the 24 heart valve (8 %) patients who had had normal preoperative evaluations. The patients with injured nerves were older and had undergone longer operation times. There were no differences between the patients with injured nerves and the others with respect to mammary artery harvesting or other operative variables. CONCLUSIONS: There are no reports in the literature of routine preoperative and postoperative electrophysiological studies in large patient groups to evaluate brachial plexus injury during open heart surgery. It is known that heart surgery sometimes causes partial brachial plexus injury, especially in the lower trunk. However, these peripheral nerve problems are usually not considered clinically important and are not investigated. Patients undergoing open heart surgery must be closely followed up for peripheral nerve injury during the postoperative period.

A case of acquired stuttering resulting from left parietal infarction.

OBJECTIVE: Acquired stuttering is uncommon, and is reported anecdotally after head injury and cerebrovascular diseases. Although this entity is described to occur in lesions of dominant hemisphere, it is rarely shown to occur in non-dominant hemispheric and subcortical lesions, too. Therefore we described a case with this rare syndrome and we discussed the possible mechanisms, lesion locations and medical treatment of stuttering according to previous reports. CASE REPORT: A 61-year-old right-handed man with sudden onset of right hemiparesia and stuttering without aphasia is reported. There was a circumscribed cortical infarction in the left parietal cortex on computerized tomography (CT) and magnetic resonance imaging (MRI) showed a recent infarct. Single photon emission computed tomography (SPECT) images evidenced perfusion abnormalities in the same region. He never stuttered before and has no family history of stuttering. He has been maintained on antiaggregant and paroxetine treatment. CONCLUSION: A rare presentation of stroke associated with stuttering is reported and the treatment of stuttering with paroxetine is discussed.

The histopathological effects of thiodan on the liver and gut of mosquitofish, Gambusia affinis.

Thiodan (33.7% endosulfan), a polychlorinated cyclodiene insecticide, was evaluated for its histopathological effects on mosquitofish, Gambusia affinis, by light microscopy. Fish were exposed to doses of 0.00 (control), 1.00, 2.50, and 5.00 microg/L on days 7, 14, 21, and 30. No histopathological effects were apparent at control group. The histopathological alterations were characterized as oedema, degeneration, accumulation of lymphocytes in the lamina propria, disintegration of villuses, pycnotic state of nuclei, and necrosis in gut; degeneration, hypertrophy, sinusoids enlargement, hemorrhage, pycnosis position of nuclei, vacuolization of cell cytoplasm, infiltration of mononuclear lymphocyte, and congestion in liver. These alterations were time- and dose-dependent.

Bilaterally persistent horizontal gaze palsy and facial palsy caused by pontine infarction.

Tegmental pontine infarctions make up only a small portion of all isolated pontine infarcts. These lesions cause isolated cranial nerve palsies, neuro-ophthalmologic signs, and sensory deficits. Clinical and anatomic correlation of these lesions has been made simple with the use of cranial magnetic resonance imaging (MRI). In this article, we report on a 43-year-old hypertensive woman with bilateral horizontal gaze palsy and peripheral facial paralysis but no limb weakness. Pontine paramedian tegmental infarct was visible on cranial MRI.

The distribution of extracellular matrix proteins and CD44S expression in human astrocytomas.

Aims of the study were: 1. to establish the prevalence of CD44 protein expression in human astrocytomas; 2. to compare the distribution of the extracellular matrix in these tumors; 3. to investigate the relation between CD 44, the extracellular matrix proteins and the histological grade of the tumor. CD44, Type IV Collagen (Col IV), Laminin (LN), Fibronectin (FN), and Tenascin (TN) expression were detected by immunohistochemistry in formalin fixed paraffin embedded tissue samples of 52 astrocytic tumors: 35 glioblastomas (GB), 7 Anaplastic astrocytomas (AA) and 10 astrocytomas (A). The localization of Col IV was observed in the basement membrane of the vessel walls in most of the astrocytomas (88.4%) with a similar pattern obtained with LN staining. 7 of 10 A (70%), 2 of 7 AA (28%) and 9 of 35 GB (25.7%) showed LN positivity. There was a negative correlation between LN expression and tumor grade (p=0.03). FN was either localized in the basement membrane or showed thick multi-layered immunoreactivity of the vessel walls. FN expression was seen in 6 A (60%), 4 AA (57%) and all of 35 GB (100%). The FN distribution was not uniform and its staining intensity showed decrease in GB. 3A (30%), 3 AA (42%), 27 GB (77.1%) showed TN expression in the vessel walls and in some tumor cells of 19 GBs. TN expression was positively correlated with the degree of vascular endothelial proliferation in GB (p<0.05). The expression of CD44s wasseen as plasma membrane positivity of glioma cells in 5 of 10A (50%), 3 of 7AA (42.3%) and 29 of 35 GB (82.8%). The intensity of immunoreaction was quite strong especially near the vessels. There was a good correlation between TN and CD44s expression in human astrocytic tumors (p=0.005). No relationship was observed between GFAP, ECM proteins and CD44s expression. Both CD44s and TN expression showed increase with malignancy in astrocytomas. These findings indicated that the histological malignancy of the astrocytomas was correlated with expression of TN and CD44s. It was suggested that in astrocytomas there was a biological relationship only between CD44 and TN, but none with the other ECM proteins. TN may play a role in angiogenesis in human astrocytic tumors.

Oral myiasis caused by hypoderma bovis larvae in a child: a case report.

Myiasis is the invasion of living tissue of humans and other mammals by the eggs or larvae of flies of the order of Diptera. It occurs mainly in the tropic, and is associated with inadequate public and personal hygiene. Oral myiasis in humans appears to be rare. This article records a case of oral myiasis caused by larvae of Hypoderma bovis. Two different pathologic soft tissue sockets were observed in the vestibular sulcus at the level of the both deciduous laterals along the deep upper lip tissues.

A practical test and its value in rheumatoid arthritis.

A practical test distinguishing some pathological conditions from the healthy state is described and a preliminary study on the value of this test for determining the disease activity in rheumatoid arthritis (RA) is presented. In this disease, the test was found positive in 97% of the cases, while rheumatoid factor (RF) was present in 57%, C reactive protein (CRP) in 83%, and elevated erythrocyte sedimentation rate (ESR) in 93% cases. When the activity of the disease disappeared, the test became negative. This test may be useful in RA for determining the active phase and evaluating treatment.

Pleural calcification, pleural mesotheliomas, and bronchial cancers caused by tremolite dust.

Around the town of Cermik in south-east Turkey there are many deposits of asbestiform minerals, some of which are used to make whitewash or stucco. A sample of 7000 of the population revealed 461 (6.5%) with pleural thickening and calcification, of whom 103 (1.47% of the total) had evidence of interstitial pulmonary fibrosis. Forty-one patients with respiratory cancer were admitted to the Diyarbakir Chest Hospital from around Cermik and from a comparable area of equal population (but without asbestos deposits) in 1977-8. Of these 23 were mesotheliomas, 22 coming from around Cermik. In addition, 11 of the 18 primary bronchial cancers came from around Cermik. A similar excess of mesothelioma and bronchial cancer had been admitted from the Cermik area in previous years. The whitewash or stucco material has been shown to contain fibrous tremolite and non-fibrous antigorite/lizardite, chlorite, and talc. A lung biopsy of a patient from Cermik contained large numbers of tremolite fibres, both free and forming asbestos bodies. There were only occasional chrysotile fibres.