Thoracic cystic schwannoma: case report and review of literature.

INTRODUCTION: Schwannomas are the second most common type of intra-dural lesions involving the thoracic spine. They are frequently seen as solid and heterogeneous lesions. Totally cystic thoracic schwannomas represent a rare pathological schwannoma variant, with only four cases reported in the English literature to our knowledge. CASE PRESENTATION: We report an 80-year-old male who presented with upper back pain for 3 months. Magnetic resonance imaging (MRI) showed a cystic lesion at the level of T6-T7 with peripheral contrast enhancement. The lesion was removed in total surgically with complete resolution of the patient's symptoms. DISCUSSION: The diagnosis of cystic schwannomas is often delayed due to the paucity of symptoms and the lack of meticulous investigation. The presence of rim enhancement on contrast-enhanced MRI may be the only clue for the diagnosis. It is important to consider cystic schwannomas in the differential diagnosis of cystic spinal lesions since the best surgical outcome is strongly related to earlier diagnosis and total resection of the lesion.

Evaluation of Kharma scale as a predictor of lower third molar extraction difficulty.

BACKGROUND: The Evaluation of the degree of lower third molar (L3M) extraction difficulty is extremely important for both clinicians and patients. This study aimed to evaluate the validity of a new index (Kharma scale) as a preoperative predictor index of the difficulty of surgical removal of impacted L3M. MATERIAL AND METHODS: Extraction difficulty of a series of 49-impacted L3M was predicted preoperatively by Kharma scale, and postoperative difficulty was assessed with a modified Parant scale. RESULTS: The sensitivity of Kharma scale, as a predictor of difficulty, was 18.2% and the specificity was 68.4%. Likelihood ratios for the Kharma categories also indicated that the scale is of little value for predicting a difficult extraction. There was no significant association between the Kharma score and duration of operation, but high-modified Parant scores were significantly associated with longer operations. CONCLUSIONS: The proposed Kharma scale was unreliable as preoperative predictor of the L3M extraction difficulty, and both radiological and clinical information must be taken into account.

Facial expression drawings and the full cup test: valid tools for the measurement of swelling after dental surgery.

Assessment of postoperative swelling is subjective and depends on the patient's opinion. The aim of this study was to evaluate the validity of facial expression drawings and the full cup test and to compare their performance with that of other scales in measuring postoperative swelling. Fifty patients who had one of several procedures were included. All patients were asked to fill in a form for six days postoperatively (including the day of operation) that contained four scales to rate the amount of swelling: facial expression drawings, the full cup test, the visual analogue scale (VAS), and the verbal rating scale (VRS). Seven patients did not know how to use some of the scales. However, all patients successfully used the facial expression drawings. There was a significant difference between the scale that patients found easiest to use and the others (p<0.008). Fourteen patients selected facial expression drawings and five the VRS. The results showed that the correlations between the scales were good (p<0.01). Facial expression drawings and the full cup test are valid tools and could be used to assess postoperative swelling interchangeably with other scales for rating swelling, and some patients found facial expression drawings were the easiest to use.

Window-Based Channel Impulse Response Prediction for Time-Varying Ultra-Wideband Channels.

This work proposes channel impulse response (CIR) prediction for time-varying ultra-wideband (UWB) channels by exploiting the fast movement of channel taps within delay bins. Considering the sparsity of UWB channels, we introduce a window-based CIR (WB-CIR) to approximate the high temporal resolutions of UWB channels. A recursive least square (RLS) algorithm is adopted to predict the time evolution of the WB-CIR. For predicting the future WB-CIR tap of window wk, three RLS filter coefficients are computed from the observed WB-CIRs of the left wk-1, the current wk and the right wk+1 windows. The filter coefficient with the lowest RLS error is used to predict the future WB-CIR tap. To evaluate our proposed prediction method, UWB CIRs are collected through measurement campaigns in outdoor environments considering line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios. Under similar computational complexity, our proposed method provides an improvement in prediction errors of approximately 80% for LOS and 63% for NLOS scenarios compared with a conventional method.

Statistical Modelling and Characterization of Experimental mm-Wave Indoor Channels for Future 5G Wireless Communication Networks.

This paper presents an experimental characterization of millimeter-wave (mm-wave) channels in the 6.5 GHz, 10.5 GHz, 15 GHz, 19 GHz, 28 GHz and 38 GHz frequency bands in an indoor corridor environment. More than 4,000 power delay profiles were measured across the bands using an omnidirectional transmitter antenna and a highly directional horn receiver antenna for both co- and cross-polarized antenna configurations. This paper develops a new path-loss model to account for the frequency attenuation with distance, which we term the frequency attenuation (FA) path-loss model and introduce a frequency-dependent attenuation factor. The large-scale path loss was characterized based on both new and well-known path-loss models. A general and less complex method is also proposed to estimate the cross-polarization discrimination (XPD) factor of close-in reference distance with the XPD (CIX) and ABG with the XPD (ABGX) path-loss models to avoid the computational complexity of minimum mean square error (MMSE) approach. Moreover, small-scale parameters such as root mean square (RMS) delay spread, mean excess (MN-EX) delay, dispersion factors and maximum excess (MAX-EX) delay parameters were used to characterize the multipath channel dispersion. Multiple statistical distributions for RMS delay spread were also investigated. The results show that our proposed models are simpler and more physically-based than other well-known models. The path-loss exponents for all studied models are smaller than that of the free-space model by values in the range of 0.1 to 1.4 for all measured frequencies. The RMS delay spread values varied between 0.2 ns and 13.8 ns, and the dispersion factor values were less than 1 for all measured frequencies. The exponential and Weibull probability distribution models best fit the RMS delay spread empirical distribution for all of the measured frequencies in all scenarios.

Isolation and partial characterization of Brazilian samples of feline immunodeficiency virus.

Feline immunodeficiency virus (FIV) causes a slow progressive degeneration of the immune system which eventually leads to a disease comparable to acquired immune deficiency syndrome (AIDS) in humans. FIV has extensive sequence variation, a typical feature of lentiviruses. Sequence analysis showed that diversity was not evenly distributed throughout the genome, but was greatest in the envelope gene, env. The virus enters host cells via a sequential interaction, initiated by the envelope glycoprotein (env) binding the primary receptor molecule CD134 and followed by a subsequent interaction with chemokine co-receptor CXCR4. The purpose of this study was to isolate and characterize isolates of FIV from an open shelter in São Paulo, Brazil. The separated PBMC from 11 positive cats were co-cultured with MYA-1 cells. Full-length viral env glycoprotein genes were amplified and determined. Chimeric feline × human CD134 receptors were used to investigate the receptor utilization of 17 clones from Brazilian isolates of FIV. Analyses of the sequence present of molecular clones showed that all clones grouped within subtype B. In contrast to the virulent primary isolate FIV-GL8, expression of the first cysteine-rich domain (CRD1) of feline CD134 in the context of human CD134 was sufficient for optimal receptor function for all Brazilian FIV isolates tested.

Phylogenetic characterisation of naturally occurring feline immunodeficiency virus in the United Kingdom.

Feline immunodeficiency virus (FIV) is a significant pathogen of domestic and non-domestic felids worldwide. In domestic cats, FIV is classified into five distinct subtypes (A-E) with subtypes A and B distributed most widely. However, little is known about the degree of intrasubtype viral diversity and this may prove critical in determining whether monovalent vaccines are likely to protect against FIV strains within a single subtype. Here, we characterise novel env sequences from 47 FIV strains recovered from infected cats in the United Kingdom and its environs. Phylogenetic analyses revealed that all bar one sequence belonged to subtype A, the predominant subtype in Western Europe. A single sequence was identified as a likely subtype A/C recombinant, intriguing given that subtype C does not appear to exist in either the UK or North Western Europe and suggestive of a recombination event predating its introduction into the UK. Subtype A strains from the UK were not significantly differentiated from representative subtype A isolates found elsewhere suggesting multiple introductions of FIV into the country. Divergence among isolates was comparable to that observed for subtype A isolates worldwide, indicating that FIV in the UK covers the full spectrum of subtype A diversity seen globally. This study demonstrates that while subtype A is predominant in the UK, novel introductions may result in the emergence of novel subtypes or intersubtype recombinants, potentially circumventing vaccine strategies. However, the dominance of subtype A suggests that the development of a regional or subtype-specific protective vaccine for the UK could be achievable.

Outcomes in patients with pulmonary hypertension undergoing percutaneous atrial septal defect closure.

OBJECTIVES: To examine the outcomes in patients with moderate or severe pulmonary arterial hypertension (PAH) undergoing percutaneous atrial septal defect (ASD) closure. DESIGN: Retrospective study. SETTING: Teaching hospital-based study. PATIENTS: Fifty-four patients with moderate (n = 34) or severe PAH (n = 20) who underwent successful device implantation between 1999 and 2004 were included in the study. Clinical and transthoracic echocardiographic data were reviewed. Pulmonary hypertension was classified as moderate (50-59 mm Hg) or severe (>or=60 mm Hg) according with the right ventricular systolic pressure (RVSP) calculated by echocardiography. RESULTS: At the early follow-up (mean (SD) 2.3 (1.2) months) all patients were alive and the baseline RVSP decreased from 57 (11) mm Hg to 51 (17) mm Hg (p = 0.003). At the late follow-up (n = 39, mean (SD) duration 31 (15) months) two patients had died and the baseline RVSP decreased from 58 (10) mm Hg to 44 (16) mm Hg (p = 0.004). Although the overall mean RVSP decreased at late follow-up, only 43.6% (17/39) of patients had normalisation (<40 mm Hg) of the RVSP and 15.4% (6/39) had persistent severe PAH. CONCLUSION: Transcatheter closure in patients with secundum ASD and PAH can be successfully performed in selected subjects and is associated with good outcomes. Early improvements in RVSP are seen in patients with moderate or severe PAH undergoing transcatheter ASD closure. Continued improvement in RVSP occurs in late follow-up. Despite decreases in the mean RVSP in late follow-up, many patients do not have complete normalisation of pressures.

Myxobolus infections of common carp (Cyprinus carpio) in Syrian fish farms.

During a survey on Myxobolus infection of pond-cultured common carp in Syria three Myxobolus spp. were found. Myxobolus dispar infected the gill arteries, forming large elongated plasmodia in the gill filaments. The plasmodia of M basilamellaris were located in the gill arches at the base of the filaments. Elongated filiform plasmodia of M. encephalicus were found in the blood vessels of the brain. Despite the common occurrence of the above parasites, no disease symptoms were observed in the infected fish specimens. This is the first report on myxosporean infection of fish from Syrian waters.

Safety and efficacy of rosuvastatin therapy for the prevention of hyperlipidemia in adult cardiac transplant recipients.

BACKGROUND: Hyperlipidemia after orthotopic heart transplantation (OHT) is associated with immunosuppression. Many OHT patients have increased lipid levels above published guidelines despite treatment with high doses of statins. Treatment with rosuvastatin (ROS) in OHT patients has not yet been evaluated. Therefore, we assessed its efficacy and safety in an OHT population. METHODS: Twenty-one OHT recipients, median age 66 years, whose lipid levels were sub-optimal on the highest tolerated doses of statins, received ROS in addition to standard immunosuppression. Total cholesterol (TC), low-density lipoprotein (LDL-C) and high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), liver transaminases (AST) and creatinine kinase (CK) were measured before and during treatment with ROS. RESULTS: After 6 weeks on an average ROS dose of 10 mg/day, a TC:HDL-C ratio of <4 was reached in 76% of patients, and 70% of patients reached an LDL-C level of <2.5 mmol/liter (100 mg/dl). TC decreased to <5.2 mmol/liter (200 mg/dl) in 80% of patients and TG decreased to <2 mmol/liter (175 mg/dl) in 61% of patients. Except for the HDL-C increase, all changes were statistically significant. The decrease in the median TC:HDL-C ratio between baseline and 6 weeks was also statistically significant (p = 0.001). There were no significant changes in CK or AST levels, and no clinical evidence of myositis. One patient developed myalgia and 2 were withdrawn from the study because of mild elevation of CK (<3-fold upper limit of normal [ULN]). CONCLUSIONS: In the setting of tertiary referral centers, ROS appears to be safe and effective in lowering LDL-C in OHT recipients in whom treatment with other statins failed to achieve target LDL-C. No evidence of liver or muscle dysfunction was noted. Long-term studies are needed to ascertain the effect of ROS therapy on incidence of coronary artery disease (CAD) in this population.

Reno-, hepato- and splenomegaly of common carp fingerlings (Cyprinus carpio L.) diseased in swimbladder inflammation caused by Sphaerospora renicola Dyková et Lom, 1982.

The weight of internal organs (swimbladder, kidney, liver, spleen) in relation to the body weight was studied in common carp fingerlings divided into three groups on the basis of swimbladder appearance and microscopic examination of the kidney. The fish had been collected from different Hungarian fish farms at the time when swimbladder inflammation (SBI) usually occurs (in July and August). The first group comprised fish with severe signs of SBI and massive renal sphaerosporosis, the second group consisted of fish with milder swimbladder changes and/or kidney infection by a low number of Sphaerospora renicola, while the third group was constituted by infection-free common carp fry. Statistical analysis of swimbladder, kidney, liver and spleen weight in relation to the body weight revealed that in the infected groups the internal organs were substantially enlarged. This suggests that in common carp fry with SBI the swimbladder changes are accompanied by reno-, hepato- and splenomegaly.