Multi-delay coherence imaging spectroscopy optimized for ion temperature measurements in the divertor plasma of the Wendelstein 7-X stellarator.

A new coherence imaging spectroscopy (CIS) diagnostic optimized to measure the C2+ impurity ion temperature Ti spatial distribution in the divertor plasma of the W7-X stellarator is designed, tested, and validated. Using CIS to obtain Ti in the edge of magnetically confined plasmas has historically been challenging because Doppler broadening and Zeeman splitting have comparable effects on the shape of spectral emission lines. To distinguish between these two mechanisms, a novel approach to birefringent crystal design is employed to minimize the diagnostic's sensitivity to Zeeman splitting. The recently developed pixelated multi-delay CIS approach is also used to obtain four times as much spectral information as traditional CIS approaches. The Ti-optimized CIS diagnostic is validated in a long-pulse W7-X plasma by comparison with a high-resolution spectrometer whose sightlines overlap with the CIS field of view. The CIS and spectrometer Ti profiles have the same shape and agree to within 10% on average and 25% in the worst case. Images of the Ti distribution near the divertor show toroidally elongated bands aligned with the magnetic field, with Ti ranging between 10 and 40 eV.

Prosthetic valve endocarditis secondary to Tropheryma whipplei in a patient with chronic polyarthritis.

BACKGROUND: Whipple's disease is a chronic multisystemic infectious disease that rarely presents as culture-negative endocarditis. Most patients reported with Tropheryma whipplei endocarditis involve a native valve and few describe prosthetic valve disease. CASE PRESENTATION: A patient with chronic polyarthritis and previous mitral valve replacement developed decompensated heart failure without fever. Transesophageal echocardiography revealed a prosthetic mitral valve vegetation and he underwent prosthetic mitral valve replacement. Blood and prosthetic mitral valve cultures were unrevealing. Broad-range polymerase chain reaction (PCR) of the extracted valve and subsequent Periodic-acid-Schiff (PAS) staining established the diagnosis of T. whipplei prosthetic valve endocarditis. CONCLUSION: Whipple's disease may present as culture-negative infective endocarditis and affect prosthetic valves. Histopathology with PAS staining and broad-range PCR of excised valves are essential for the diagnosis. Greater clinical awareness and implementation of these diagnostic procedures should result in an increased reported incidence of this rare disease.

Cerebral Toxoplasmosis in a Rheumatoid Arthritis Patient on Immunosuppressive Therapy.

Cerebral toxoplasmosis is a life-threatening infection most commonly found in immunocompromised hosts such as acquired immunodeficiency syndrome (AIDS) or transplant patients. However, it is not known to affect patients with chronic inflammatory disorders on immunosuppressive therapy. We describe the case of a 70-year-old female with rheumatoid arthritis (RA) on chronic therapy with methotrexate and infliximab, who presented to the hospital after two weeks of right-sided weakness. Imaging revealed bilateral ring-enhancing lesions in the basal ganglia (left greater than right). A diagnosis of cerebral toxoplasmosis was made on brain biopsy. Apart from the immunosuppressive therapy and owning a cat, she had no other risk factors for developing the infection. The patient's immunosuppressive medications were discontinued, and she was started on high-dose trimethoprim-sulfamethoxazole (TMP-SMX). Upon literature review using PubMed, we found seven other published reports on similar cases of toxoplasmosis in RA patients on immunosuppressive therapy; however, there was a lack of recommendations for diagnosis, treatment, and prophylaxis in this patient population. With the growing use of immunosuppressive therapies in chronic inflammatory disorders, further data is needed regarding the management of toxoplasmosis in these patients. This case report is an investigation of the relationship between immunosuppressive medications in RA patients and cerebral toxoplasmosis and an exploration of the available recommendations for its management.

Coherence imaging spectroscopy at Wendelstein 7-X for impurity flow measurements.

In the last decade, Coherence Imaging Spectroscopy (CIS) has shown distinctive results in measuring ion flow velocities in the edge of magnetically confined plasma devices. Its 2D spatially resolved measurement capabilities and its high optical throughput are ideal for investigating the impurity behavior in the complex 3D magnetic island topology edge of Wendelstein 7-X (W7-X). However, a highly precise and stable calibration method is required for a reliable diagnostic operation. A new level of precision and stability has been achieved for the two CIS systems installed at W7-X with the use of a new calibration source, a continuous tunable laser commercially available only since 2015. A specific prototype model was successfully adapted to the challenging requirements of W7-X, granting high accuracy (±0.01 pm) and flexibility (spectral range: 450-650 nm) in the wavelength calibration required for measuring low-Z impurity ion flow velocities. These features opened up new investigation possibilities on temperature stability and wavelength response of the CIS components, allowing to fully characterize and validate the W7-X systems. The CIS diagnostic was operational throughout the last W7-X experimental campaign. Measured velocities on the order of ∼20-30 km/s were observed, corroborated by comparisons with measurements with Mach probes.

Cryptococcal osteomyelitis: a report of 5 cases and a review of the recent literature.

Cryptococcus neoformans is a fungal pathogen associated with advanced HIV disease and other disorders associated with immune dysfunction. The pulmonary and the central nervous system are the most common manifestations of the disease. Localised osteomyelitis as the sole manifestation of extrapulmonary disease is rare. Herein, we present five cases of Cryptococcus osteomyelitis as the only manifestation of extrapulmonary disease. We also identified 84 additional cases of isolated cryptococcal osteomyelitis in the literature. Using these data, we have made some general recommendations regarding an approach to treatment of this uncommon clinical entity.

Influence of a total joint infection control bundle on surgical site infection rates.

Quality improvement initiatives combined with pulsed xenon ultraviolet room disinfection were implemented to reduce surgical site infections (SSIs) in patients undergoing total joint procedures. After 12 months, knee SSIs were reduced from 4 to 0 (P = .03) and hip SSIs were reduced from 3 to 0 (P = .15) for a combined prevention of 7 SSIs (P = .01) and a savings of $290,990.

The occurrence of semicarbazide in the meat and shell of Bangladeshi fresh-water shrimp.

There is evidence that semicarbazide (SEM), a marker for the banned nitrofuran nitrofurazone, can arise from other, unrelated sources. Recently, Belgium rejected 54 consignments of Bangladeshi freshwater shrimp (Macrobrachium rosenbergii), following a laboratory decision to test meat and exoskeleton combined. To study the possible natural occurrence of SEM in wild shrimp, samples were collected and analysed from 29 sites across Bangladesh. SEM (<1.0 µg/kg) was detected in ∼65% of meat samples. However, SEM concentrations were approximately 100 times higher in the exoskeleton, and were unrelated to sampling location, strongly suggesting natural occurrence. In meat, most SEM was surface-associated. When the shrimp was shelled, some of the epidermal layer (which synthesises new exoskeleton) remained with the shell and some remained with the meat--leading to differing levels of natural SEM on the shrimp surface. This has implications for the use of SEM and the analytical strategy used to control nitrofuran use.

Study of common functional genetic polymorphisms of FCGR2A, 3A and 3B genes and the risk for cryptococcosis in HIV-uninfected patients.

A pilot candidate gene association study was conducted to investigate the role of three common functional genetic polymorphisms of the low-affinity Fc gamma receptors, FCGR2A (131H/R), FCGR3A (158F/V) and FCGR3B (NA1/NA2) in Cryptococcus neoformans infections in individuals not infected with HIV. The FCGR2A 131RR and FCGR3A 158VV genotypes were over-represented [OR: 1.67 (1.05-2.63) and 2.04 (1.06-4.00), respectively] whereas the FCGR3B NA2NA2 was under-represented in patients with cryptococcosis (28% vs. 40% in controls). An analysis of haplotypes showed a significant difference in distribution between cases and controls overall and in Caucasians.

Myocardial involvement in rocky mountain spotted fever: a case report and review.

Rocky Mountain Spotted Fever (RMSF), caused by Rickettia rickettsii, is a serious tickborne illness that is endemic in the southeastern United States. Although it is most commonly known as a cause of fever and rash, it can have systemic manifestations. The myocardium may rarely be involved, with symptoms that can mimic those of acute coronary syndromes. This report describes a case of serologically proven RMSF causing symptomatic myocarditis, manifested by chest pain, elevated cardiac enzyme levels, and decrease myocardial function. After treatment with antibiotics, the myocarditis resolved. Thus, although unusual, the clinician should be aware of myocardial disease in patients with appropriate exposure histories or other clinical signs of RMSF. Close monitoring and an aggressive approach are essential to reduce mortality rates.

Hypercalcemia caused by iatrogenic hypervitaminosis A.

Vitamin A toxicity produces protean clinical manifestations involving a wide variety of tissues and systems. Hypercalcemia can occasionally be associated with high vitamin A levels, but is rare. In this report we describe a patient who was receiving a commercially prepared enteral feeding formula for 2 years. He developed asymptomatic hypercalcemia and had serum vitamin A levels several fold above normal. Subsequently, a custom-made enteral feed was used which contained negligible amounts of vitamin A. Several months later, vitamin A levels diminished substantially and serum calcium levels returned to normal.

Risk-taking and health-seeking behavior in men with a history of urethritis: is there a learning curve?

BACKGROUND AND OBJECTIVES: Studies addressing how past experience with sexually transmitted diseases (STD) influence health-seeking behaviors among at-risk men are few. GOAL: The goal of this study was to determine whether health-seeking behaviors among men diagnosed with urethritis differ based on whether they report prior urethritis. STUDY DESIGN: Male STD clinic attendees answered a questionnaire regarding their demographic, sexual, and health-seeking characteristics. The men were stratified based on whether they reported prior urethritis. RESULTS: Of 466 men, 297 reported prior urethritis. Symptomatic men diagnosed with urethritis who reported prior urethritis did not recognize their symptoms as a possible STD earlier than those reporting no urethritis history; there was also no difference between the groups in their interval to presenting for care once symptoms were recognized as a possible STD. Furthermore, men with prior urethritis were as likely to engage in sex acts once they recognized their symptoms as a possible STD manifestation. CONCLUSION: Compared with men without prior urethritis, men with urethritis symptoms who reported prior urethritis did not recognize symptoms earlier, alter health-seeking behavior, or curtail sexual activity.

Comparison of STD burden and risk among men with and without regular doctors attending a southern urban STD clinic.

BACKGROUND: Studies addressing health-seeking behaviors among men at risk for STD are few; this study examines how having a regular doctor might influence risk-taking or STD prevalence. GOAL: The goal was to examine demographic, sexual, and health-seeking characteristics of male STD clinic attendees. STUDY DESIGN: Randomly selected men attending an STD clinic answered a questionnaire regarding the aforementioned characteristics. The men were stratified according to whether they reported having a regular doctor. RESULTS: Of 467 men, 32% reported a regular doctor. These men were more likely to be older, to be better educated, and to state they would seek care for a medical problem at a doctor's office. The two groups did not differ in STD history or prostitute exposure; men without doctors were more likely to have urethritis and STD, although the men with doctors had substantial STD rates. CONCLUSION: Public health clinics remain an important safety net for the management of STD, even for men who report a regular doctor.

The differentiation of skeletal muscle cells involves a protein-tyrosine phosphatase-alpha-mediated C-Src signaling pathway.

Protein-tyrosine phosphatase-alpha (PTPalpha) plays an important role in various cellular signaling events, including proliferation and differentiation. In this study, we established L6 cell lines either underexpressing or overexpressing PTPalpha by stable transfection of cells with antisense PTPalpha or with full-length wild-type human or mouse or double catalytic site Cys --> Ala mutant (DM8) PTPalpha cDNA. Expression of PTPalpha in these cell lines was determined by immunoblotting and immunofluorescence. Cells harboring antisense PTPalpha exhibited a significantly reduced growth rate and thymidine incorporation when compared with the wild-type L6 cells. In contrast, cells overexpressing PTPalpha showed more rapid (2-fold) proliferation. Myoblasts with diminished PTPalpha failed to undergo fusion and did not form myotubes in reduced serum whereas overexpression of PTPalpha promoted myogenesis 2 days earlier than wild-type L6 cells. Overexpression of phosphatase-inactive mutant PTPalpha recapitulated the phenotype of the antisense cells. The different myogenic activities of these cell lines were correlated with the expression of myogenin and creatine kinase activity. Consistent with previous reports, PTPalpha positively regulated the activity of the protein-tyrosine kinase Src. Treatment of L6 cells with PP2 or SU6656, specific inhibitors of Src family kinases, and transient transfection of dominant-inhibitory Src inhibited the formation of myotubes and expression of myogenin. Moreover, enhanced expression of PTPalpha and activation of Src was detected during myogenesis. Together, these data indicate that PTPalpha is involved in the regulation of L6 myoblast growth and skeletal muscle cell differentiation via an Src-mediated signaling pathway.

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