Branching of High-Current Relativistic Electron Beam in Porous Materials.

Propagation of high-current relativistic electron beam (REB) in plasma is relevant to many high-energy astrophysical phenomena as well as applications based on high-intensity lasers and charged-particle beams. Here, we report a new regime of beam-plasma interaction arising from REB propagation in medium with fine structures. In this regime, the REB cascades into thin branches with local density a hundred times the initial value and deposits its energy 2 orders of magnitude more efficiently than that in homogeneous plasma, where REB branching does not occur, of similar average density. Such beam branching can be attributed to successive weak scatterings of the beam electrons by the unevenly distributed magnetic fields induced by the local return currents in the skeletons of the porous medium. Results from a model for the excitation conditions and location of the first branching point with respect to the medium and beam parameters agree well with that from pore-resolved particle-in-cell simulations.

Coherent Subcycle Optical Shock from a Superluminal Plasma Wake.

We propose exploiting the superluminal plasma wake for coherent Cherenkov radiation by injecting a relativistic electron beam (REB) into a plasma with a slowly varying density up-ramp. Using three-dimensional particle-in-cell and far-field time-domain radiation simulations, we show that an isolated subcycle pulse is coherently emitted towards the Cherenkov angle by bubble-sheath electrons successively at the rear of the REB-induced superluminal plasma wake. A theoretical model based on a superluminal current dipole has been developed to interpret such coherent radiation, and agrees well with the simulation results. This radiation has ultrashort attosecond-scale duration and high intensity, and exhibits excellent directionality with ultralow angular divergence and stable carrier envelope phase. Its intensity increases with the square of the propagation length and its central frequency can be easily tuned over a wide range, from the far infrared to the ultraviolet.

Treatment of male breast cancer: meta-analysis of real-world evidence.

BACKGROUND: Breast cancer is rare in men and managed by extrapolating from breast cancer in women. The clinicopathological features of male breast cancer, however, differ from those of female breast cancer. Because clinical trials are rare, the synthesis of real-world data is one method of integrating sufficient evidence on the optimal treatment for this patient population. METHODS: PubMed, Embase, and Cochrane Library databases were searched. Clinical studies were included if they evaluated the treatments of interest in male breast cancer; these evaluations included breast-conserving surgery (BCS) versus mastectomy, postmastectomy radiation therapy versus no radiation, the accuracy of sentinel lymph node biopsy (SLNB), and a comparison of various endocrine therapies. RESULTS: Forty studies were retrieved. The pooled estimate of overall survival (OS) revealed no difference between BCS and mastectomy groups. Postmastectomy radiation to the chest wall significantly increased OS relative to no postmastectomy radiation (hazard ratio (HR) 0.67, 95 per cent confidence interval 0.54 to 0.84). The pooled estimates of identification and false-negative rates of SLNB were 97.4 and 7.4 per cent respectively. Tamoxifen treatment was associated with significantly increased OS compared with no tamoxifen intake (HR 0.62, 0.41 to 0.95). CONCLUSION: Identification and false-negative rates for SLNB were comparable to those in female breast cancer. Breast-conserving surgery can be effective and safe; postmastectomy radiation to the chest wall and 5-year tamoxifen treatment improves survival.

Nanoscale Electrostatic Modulation of Mega-Ampere Electron Current in Solid-Density Plasmas.

Transport of high-current relativistic electron beams in dense plasmas is of interest in many areas of research. However, so far the mechanism of such beam-plasma interaction is still not well understood due to the appearance of small time- and space-scale effects. Here we identify a new regime of electron beam transport in solid-density plasma, where kinetic effects that develop on small time and space scales play a dominant role. Our three-dimensional particle-in-cell simulations show that in this regime the electron beam can evolve into layered short microelectron bunches when collisions are relatively weak. The phenomenon is attributed to a secondary instability, on the space- and timescales of the electron skin depth (tens of nanometers) and few femtoseconds of strong electrostatic modulation of the microelectron current filaments formed by Weibel-like instability of the original electron beam. Analytical analysis on the amplitude, scale length, and excitation condition of the self-generated electrostatic fields is clearly validated by the simulations.

Reduction of postural nasal resistance following oropharyngeal surgery in patients with moderate-severe obstructive sleep apnea.

BACKGROUND: Patients with obstructive sleep apnea (OSA) have elevated nasopharyngeal resistances due to increased turbulent airflow. The study aims to investigate the effect of oropharyngeal surgery on nasal resistance in patients with various severity levels of OSA. METHODOLOGY: Patients with greater or equal to 5 events hourly on the apnea-hypopnea index (AHI) were enrolled. Patients with retropalatal obstruction underwent uvulopalatopharyngoplasty, while patients with concurrent retrolingual obstruction under- went uvulopalatopharyngoplasty (UPPP) plus tongue base suspension. Before surgery and after surgery, subjective outcomes were assessed using a visual analog scale (VAS), and objective outcomes were assessed using overnight polysomnography and rhinomanometry. The limitation of the study was that UPPP instead of expansion sphincter pharyngoplasty was performed in this study. RESULTS: Sixty-two patients were enrolled, while 30 patients were diagnosed as mild OSA (group Mild) and 32 patients were mo- derate-severe OSA (group MS). The preoperative VAS of nasal obstruction in recumbency during sleep was significantly reduced after surgery in group MS. However, no significant differences between preoperative and postoperative VAS were found in group Mild. The postoperative anterior and posterior total nasal resistances (TNR) in sitting and supine positions were not significantly different from those before surgery in group. In contrast, the postoperative posterior TNR in supine position was 0.292±0.301(Pa/ cm3/s), compared with 0.425±0.343(Pa/cm3/s) preoperatively. CONCLUSIONS: Oropharyngeal surgery improves nasal obstruction during sleep and lowers the supine TNR measured in poste- rior rhinomanometry in patients with moderate-severe OSA. Oropharyngeal surgery is a possible treatment for postural nasal obstruction in patients with moderate-severe OSA.

Chitosan films promote formation of olfactory neurospheres and differentiation of olfactory receptor neurons.

BACKGROUND: Olfactory dysfunction significantly impairs the life quality of patients. Therefore, a model needs to be developed for anosmia. Chitosan is a biodegradable natural polysaccharide that has been widely studied for regenerative purposes in the nervous system. However, whether chitosan promotes differentiation of olfactory receptor neurons or regulates formation of neurospheres in the olfactory system remains unexplored. METHODOLOGY: Olfactory neuroepithelial cells were isolated from embryonic wistar rats on day 17, and cultured on controls and chitosan films for 12 days. The effects of treatment were assessed using immunocytochemistry, quantitative polymerase chain reaction and western blots following culturing. The substrate of poly-L-lysine-co-laminin was adopted as a control. RESULTS: In contrast to the flat layer on controls, olfactory neuroepithelial cells form olfactory neurospheres on chitosan films with steadily increasing diameter. The olfactory neurospheres contain basal cells, as well as immature and mature olfactory receptor neurons. The expression level of olfactory marker protein is higher on chitosan films than those on controls in gene and protein levels, and the olfactory transduction elements also express a similar trend. Mature olfactory receptor neurons are found predominantly at the periphery of the olfactory neurospheres. CONCLUSIONS: Chitosan films not only facilitate formation of olfactory neurospheres, but also promote differentiation of olfactory receptor neurons. Chitosan is a potential biomaterial to establish an in vitro culture model to treat olfactory dysfunction in future.

Effects of comorbidity and medication use on the haemodynamic status during office-based laryngeal procedures: A prospective cohort study.

OBJECTIVE: Office-based laryngeal procedures (OBLPs) are emerging as effective alternative modalities for vocal disorders. This study systematically investigates the haemodynamic status of patients, specifically focusing on the potential effects of underlying comorbidity and medication use. DESIGN: Prospective cohort study. SETTING: Tertiary referral centre. PARTICIPANTS: We prospectively recruited 214 consecutive patients who received OBLPs during January-December 2015. All procedures were performed under local anaesthesia without sedation, in an upright (sitting) position. MAIN OUTCOME MEASURES: We measured heart rate (HR), systolic and diastolic blood pressure, and oxygen saturations at baseline (before procedure), immediately after local anaesthesia to the pharynx and larynx, immediately after completing of procedure, and 20 minutes after the procedure. RESULTS: Systolic, diastolic blood pressures and HR all significantly increased after local anaesthesia, and gradually decreased after the procedure (P<.01). Oxygen concentration remained unchanged. Patients with comorbidity and those receiving vasoactive medications showed significantly higher perioperative blood pressures than the other patients (P<.05), but the trend remained similar. Prominent hypertension (systolic ≥160 mm Hg or diastolic ≥100 mm Hg) was noted in 17 patients, more commonly in patients with older age, higher baseline blood pressures and receiving vasoactive medications. Only 2% of patients with normal baseline measurements developed prominent hypertension perioperatively. Tachycardia (HR≥100 bpm) developed in 22 patients, more frequently in patients with higher baseline HRs, and perceiving greater discomforts. CONCLUSION: This study revealed that routine haemodynamic monitoring may not be necessary for all the OBLPs, but should be considered for older patients, those with higher baseline blood pressure or HR, sensitive patients who might be more susceptible to perioperative discomfort, and those receiving vasoactive medications.

Assessment of carotid artery intima-media thickness in patients with obstructive sleep apnoea.

OBJECTIVE: This study compares the carotid intima-media thickness (CIMT) in different severity of obstructive sleep apnoea (OSA) patients and assesses the role of OSA in carotid artery vasculopathy with control of multiple co-morbidities. STUDY DESIGN: Prospective case-control study. SETTING: Tertiary referral centre. PARTICIPANTS: This study recruited 36 volunteers without the complaints of sleep-disordered breathing, 27 patients with mild-moderate OSA and 39 patients with severe OSA. MAIN OUTCOME MEASURES: The CIMT was measured using a Toshiba Aplio 500 ultrasound system (Otawara, Japan) with a 5-14 MHz L probe. RESULTS: Bilateral and mean CIMT in healthy control, mild-moderate OSA and severe OSA were 0.69 ± 0.14, 0.72 ± 0.24 and 0.94 ± 0.33, respectively (P < 0.01 in anova test). Post hoc tests show that the severe OSA group had significantly higher mean CIMT than the control and mild-moderate OSA groups (P < 0.01). With the cut-off as 1 mm, the increased risks of cardiovascular disease (CVD) for mild-moderate and severe OSA were 11% and 39%, respectively, while no patient in the healthy control group was at risk of CVD. Multivariate linear regression could not prove that OSA itself was an independent factors for increased CIMT (mild-moderate OSA ß: 0, [-0.12, 0.13]; severe OSA ß: 0.08, [-0.06, 0.22], both P > 0.05) after adjusting age, hypertension and body mass index. CONCLUSION: Automated measurement of the CIMT can be a useful tool for CVD risk assessment in patients with OSA. Severity of OSA may be an intermediate factor between multiple co-morbidities and carotid atherosclerotic change.

Empyema caused by Anaeroglobus geminates, a case report with literature review.

Little is known about the virulence and clinical impact on humans from infection with Anaeroglobus geminates, an anaerobic gram-negative coccus belonging to the family Veillonellaceae. We report the first case of an Anaeroglobus geminates invasive infection in humans characterized by pneumonia complicated with empyema. The pathogen was initially identified as Veillonella spp. by an automatic identification system (Becton-Dickinson and Company, Franklin Lakes, NJ, USA) and definitively identified following 16S ribosomal RNA gene sequence analysis. The patient was cured by surgical decortication and antimicrobial therapy. In this case, the combination of effective antibiotics, surgical intervention, and adequate drainage successfully cured the patient.

Metastatic Lung Cancer Presenting as Thoracic Empyema in an Old Patient.

An 83-year old male presented to the emergency department with productive cough and acute shortness of breath. Imaging, biochemical and microbiological studies of the pleural fluid indicated empyema. After antibiotic treatment and tube drainage, symptoms of the patient persisted and he received thoracoscopic decortication. His condition improved gradually, but histopathological examination showed metastatic adenocarcinoma of the lung. Clinicians are alerted to the possible association of malignant tumours and empyema in older patients.

The optimal duration of compression therapy following varicose vein surgery: a meta-analysis of randomized controlled trials.

OBJECTIVE: The optimal duration of compression therapy following varicose vein surgery of the great saphenous vein (GSV) remains controversial. Therefore, the aim of this study was to evaluate different durations of compression therapy after varicose vein surgery and their outcomes. DESIGN: A systematic review and meta-analysis of randomized controlled trials (RCTs). METHODS: Outcomes from short-duration (3-10 d) and long-duration (3-6 wk) compression therapy after GSV stripping and phlebectomies were evaluated. Pain was assessed post surgery using a visual analog scale. Secondary outcomes included leg volume, complications, and the duration of absenteeism from work. RESULTS: We identified 4 RCTs published between 1991 and 2009 that evaluated 686 patients. We observed non-significant differences in postoperative pain scores between the long-duration and short-duration groups, with a weighted mean difference of -0.03 (95% confidence interval (CI): -0.53 to 0.47) at 4 weeks, and -0.01 (95% CI: -0.31 to 0.33) at 6 weeks, postoperatively. We also observed non-significant differences in the incidence of postoperative complications (risk ratio: 0.84, 95% CI: 0.60-1.18), and changes in leg volume, 4 weeks postoperatively (P = .18) between the groups. CONCLUSION: Our study results indicate that there are no benefits to long-term compression therapy after varicose vein surgery of the GSV regarding postoperative pain, leg volume, incidence of complications, and duration of absenteeism from work.

Three-dimensional analysis of the surface registration accuracy of electromagnetic navigation systems in live endoscopic sinus surgery.

BACKGROUND: Studies on the performance of surface registration with electromagnetic tracking systems are lacking in both live surgery and the laboratory setting. This study presents the efficiency in time of the system preparation as well as the navigational accuracy of surface registration using electromagnetic tracking systems. METHODOLOGY: Forty patients with bilateral chronic paranasal pansinusitis underwent endoscopic sinus surgery after undergoing sinus computed tomography scans. The surgeries were performed under electromagnetic navigation guidance after the surface registration had been carried out on all of the patients. The intraoperative measurements indicate the time taken for equipment set-up, surface registration and surgical procedure, as well as the degree of navigation error along 3 axes. RESULTS: The time taken for equipment set-up, surface registration and the surgical procedure was 179 +- 23 seconds, 39 +- 4.8 seconds and 114 +- 36 minutes, respectively. A comparison of the navigation error along the 3 axes showed that the deviation in the medial-lateral direction was significantly less than that in the anterior-posterior and cranial-caudal directions. CONCLUSION: The procedures of equipment set-up and surface registration in electromagnetic navigation tracking are efficient, convenient and easy to manipulate. The system accuracy is within the acceptable ranges, especially on the medial-lateral axis.

X-Ray spectra and electronic correlations of FeSe(1-x)Te(x).

Critical issues concerning emerging Fe-based superconductors include the degree of electron correlation and the origin of the superconductivity. X-Ray absorption spectra (XAS) and resonant inelastic X-ray scattering spectra (RIXS) of FeSe(1-x)Te(x) (x = 0-1) single crystals were obtained to study their electronic properties that relate to electron correlation and superconductivity. The linewidth of Fe L(2,3)-edges XAS of FeSe(1-x)Te(x) is narrower than that of Fe-pnictides, revealing the difference between their hybridization effects and localization character and those of other Fe-pnictides. While no significant differences exist between the Fe L-edge XAS and RIXS of FeSe(1-x)Te(x) and those of Fe-pnictides, Se K-edge and Te K-edge XAS exhibit substantial edge shift, suggesting that the superconductivity in an Fe-Se superconductor is strongly associated with the ligand states. A comparison of the Se K-edge and Te K-edge spectra reveals that the charge transfer may occur between Se and Te. Given the Coulomb interaction and the bandwidth, the spectral results indicate that FeSe(1-x)Te(x) is unlikely to be a weakly correlated system unlike the Fe-pnictides of the "1111" and "122" families. The spectral results further demonstrate that superconductivity in this class of Fe-based compounds is strongly associated with the ligand 4p hole state.

Cystic pulmonary tuberculoma.

Pulmonary tuberculosis (TB) is a medical and social problem, particularly in developing countries. Early diagnosis and treatment is important. Chest radiography is usually the first diagnostic tool when there is a suspicion of pulmonary TB. A computed tomography (CT) scan provides more accurate information on the extent and distribution of pulmonary TB. We present here a young, immunocompetent male patient with unusual imaging findings for pulmonary TB. We discuss the clinical presentation and management.

Should the pectus bar be removed before pregnancy? Two case reports.

The Nuss procedure is a minimally invasive repair for pectus excavatum in children and adults. However, it is unclear whether or not the stainless steel bar should be removed before pregnancy. We report on two adult females who had undergone a Nuss repair for pectus excavatum and successfully delivered prior to removal of the pectus bar.

Basal lamina heterogeneity in the glomerular capillary tufts of human kidneys.

Two classes of glomerular basal laminas are identified with a newly developed guanidine technique. The electron-opaque epithelial basal lamina is the most prominent element of the glomerular basal lamina scaffold. It is a continuous layer within each glomerulus, folding into capillary tufts and loops, but never completely encircling the entire circumference of each capillary, similar to the serosa covering the intestinal loop and mesentery. The vascular space so defined is further partitioned into individual capillary lumen by an electron-lucent mesangial basal lamina, that forms a meshwork continuous with the vascular pole of the glomerulus and extends peripherally to surround capillary lumens. The latter, designated endothelial basal lamina, is extremely attenuated and appears as a vestigial structure in glomerular capillary loops. Changes in juxtamesangial epithelial basal lamina indicate that it may be the site of the bulk removal and renewal of the epithelial basal lamina. The unique epithelial origin of glomerular capillary basal lamina and its organization provide a structural basis for understanding the glomerular physiology gained by various tracer studies. The results also suggest that the guanidine technique may be a useful new approach to the analysis of basal lamina alterations in various glomerular diseases.

Podoendin. A new cell surface protein of the podocyte and endothelium.

A new cell surface protein, podoendin, has been identified in Sprague-Dawley rats, and isolated using monoclonal antibody (mAb) G4. The distribution of podoendin is restricted to the surface of glomerular podocytes, urinary surface of the parietal epithelium of Bowman's capsule, and the luminal surface of endothelial cells. The antibody does not crossreact with podocytes or endothelia of human or mice. In newborn rats, the appearance of podoendin on glomerular epithelium is attendant on podocyte differentiation during glomerulogenesis of metanephrogenic vesicles. It disappears when podocytes retract and efface foot processes in tissue culture. Thus, podoendin appears to be a cell differentiation-dependent surface protein of podocytes. Podoendin is a protein of 62 kD mobility on 5% polyacrylamide gel electrophoresis. It stains intensely with Coomassie blue, but gives negative reactions to carbohydrate (periodic acid/Schiff reaction) and polyanions (alcian blue, colloidal iron, and carbocyanine). It is distinct from the major sialoglycoprotein of podocyte fuzzy coat, podocalyxin (11). Podoendin isolated and purified from endothelium of lungs appears to be identical with that from podocytes and endothelium of kidneys. Injection of mAb G4 into left ventricle of rats resulted in intense decoration of the endothelium and podocyte surface within 30 min. The decoration persisted throughout the 3-d period of observation. This was not accompanied by complement (C3) fixation. Preliminary results showed that the rats developed moderate proteinuria (100 mg/ml protein in urine), which was associated with the presence of hyaline droplets in renal tubules, on the third day. The proteinuria was not accompanied by effacement of podocyte pedicels. There were no morphologic alterations indicating glomerular or vascular injury in the kidneys.

Vagus nerve schwannoma in the middle mediastinum.

Intrathoracic neurogenic tumors are generally located in the posterior mediastinum. They usually arise from an intercostal nerve or a sympathetic chain. Tumors originating from the vagus nerve in the middle mediastinum are extremely rare. This report describes a patient with a huge intrathoracic schwannoma of the vagus nerve in the middle mediastinum and reviews the literature.

Pulmonary carcinosarcoma in a 25-year-old male patient--a case report.

Pulmonary carcinosarcoma is a rare malignancy composed of epithelial and mesenchymal elements. In general, these neoplasms occur in older individuals at the age of 60 on average and are more commonly found in males who are heavy smokers. We report a 25-year-old male with a tumour shadow of the right middle lobe that was revealed by chest X-ray during a health checkup and was confirmed by subsequent computed tomography. The patient underwent thoracotomy with right middle lobe lobectomy. Histological examination of the resected specimen showed adenocarcinoma and undifferentiated sarcoma components. The clinical and histopathologic features of this rare tumour are discussed with a review of the literature.

Prognostic value of 18-FDG uptake in early stage NSCLC.

BACKGROUND: We assessed whether the standard uptake of 18-fluorodeoxyglucose (18-FDG) in non-small cell lung cancers (NSCLC) differed between stage I and non-stage I tumors. METHODS: We reviewed 163 patients with NSCLC who underwent surgical lymph node dissection after tumor resection in 2002-2003. Patients with clinical stage I NSCLC who were investigated with preoperative positron emission tomography integrated computed tomography (PET-CT) scans using 18-FDG uptake were included; those with N2 disease were excluded. We reviewed 55 patients with a mean follow-up of 68 months. RESULTS: We analyzed 36 patients with stage I (Group 1) and 19 patients with non-stage I NSCLC (Group 2; 8 stage II, 7 stage III and 4 stage IV). There were no statistical differences in sex, age, tumor size, histological type, location or tumor differentiation between the groups. Group 1 had lower maximum standard 18-FDG uptake values (SUVmax) than Group 2 (4.9 +/- 2.7 vs. 8.1 +/- 3.8; P = 0.001). Using multiple logistic regression, patients with higher preoperative SUVmax and serum carcinoembryonic antigen (CEA) levels showed advanced tumor stages postoperatively (SUVmax > 4.7, odds ratio 7.65; CEA > 3.5 ng/mL, odds ratio 8.39). High 18-FDG uptake was significantly associated with reduced median survival (62.69 months for SUVmax < 4.7 and 40.89 months for SUVmax > 4.7). CONCLUSIONS: High preoperative 18-FDG uptake of tumors was significantly associated with reduced overall patient survival. The SUVmax of the tumor and serum CEA levels demonstrated aggressive tumors and could be helpful preoperatively when considering patients for induction therapy or resection.