Overview of the beam emission spectroscopy diagnostic system on the National Spherical Torus Experiment.

A beam emission spectroscopy (BES) system has been installed on the National Spherical Torus Experiment (NSTX) to study ion gyroscale fluctuations. The BES system measures D(α) emission from a deuterium neutral heating beam. The system includes two optical views centered at r/a≈0.45 and 0.85 and aligned to magnetic field pitch angles at the neutral beam. f/1.5 collection optics produce 2-3 cm spot sizes at the neutral beam. The initial channel layout includes radial arrays, poloidal arrays, and two-dimensional grids. Radial arrays provide coverage from r/a≈0.1 to beyond the last-closed flux surface. Photodetectors and digital filters provide high-sensitivity, low-noise measurements at frequencies of up to 1 MHz. The BES system will be a valuable tool for investigating ion gyroscale turbulence and Alfvén/energetic particle modes on NSTX.

A clinical review of 105 patients with PFAPA (a periodic fever syndrome).

AIMS: We describe the presentations and clinical outcomes of pediatric patients diagnosed with PFAPA (Periodic Fever, Aphthous lesions, Pharyngitis, and cervical Adenitis). MATERIALS AND METHODS: The medical records of children with recurrent fever and referred between 1998 and 2007 to a tertiary pediatric care hospital were reviewed. Children who met clinical criteria for PFAPA were then asked to participate in a follow-up study. RESULTS: One hundred and five children met study criteria for PFAPA which included at least six episodes of periodic fever. Most (62%) were males, the mean age at onset of PFAPA was 39.6 months (80% were <5 years at onset), the mean duration of individual fever episodes was 4.1 days, and the mean interval between episodes was 29.8 days. Accompanying signs and symptoms included aphthous stomatitis (38%), pharyngitis (85%), cervical adenitis (62%), headache (44%), vomiting with fever spikes (27%) and mild abdominal pain (41%). A prodrome (usually fatigue) preceded the fever in 62% of patients. Parents noted that when their child with PFAPA had fever, other family members remained well. Laboratory tests in patients with PFAPA were nonspecific. Individual episodes of fever usually resolved with a single oral dose ( approximately 1 mg/kg) of prednisilone. The interval between fever episodes shortened in 50% of patients who used prednisilone. PFAPA resolved spontaneously (mean length 33.2 months) in 211105 (20%) patients. PFAF'A episodes continued (mean length 23 months) at the end of this study in 661105 (63%) patients. Cimetidine therapy was associated with the resolution of the fevers in 7/26 (27%) patients; tonsillectomy was associated with the resolution of the fevers in 11/11 (100%) patients. CONCLUSION: PFAPA can usually be defined by its clinical characteristics. Individual febrile episodes usually resolve dramatically with oral prednisilone. The cause of PFAPA is unknown and research is needed to define its etiology. The overall prognosis for children with PFAPA is excellent.

Rho overexpression leads to mitosis-associated detachment of cells from epithelial sheets: a link to the mechanism of cancer dissemination.

Dissemination of neoplastic cells from the primary tumor (invasion and metastasis) is a fundamentally dangerous step in multistage carcinogenesis. Recent evidence suggests that Rho GTPase-mediated signaling is linked to dissemination of cells from several different types of human tumors. The Rho family of proteins is typically associated with the regulation of cytoskeletal activity, including actin assembly, microtubule dynamics, and myosin II-dependent contractility of the actin-rich cortex. We examined the effect of overexpression of constitutively active RhoA on islands and monolayers of epithelial cells. Although newly plated cells initially formed small spread islands, there was also a significant population of cells that detached from the substrate, floated in the medium, and then could reattach to the substrate to form new colonies. Detachment of cells from transfected epithelial islands or monolayers occurred in correlation to the plane of cytokinesis after misorientation of the mitotic spindle axis. We suggest that these alterations result from Rho-induced increase of contractility of the cortex of dividing cells, which, during cytokinesis, produces a cell that has budded out of an existing layer of cells. Cell division-mediated detachment of cells from tissue structures may be an important mechanism of tumor dissemination and metastasis.

Rho-dependent formation of epithelial "leader" cells during wound healing.

The motile behavior of epithelial cells located at the edge of a large wound in a monolayer of cultured cells was analyzed. The initial cellular response is alignment of the edge with an accompanying formation of tangential marginal actin bundles within individual cells positioned along the wound edge. Later, coherent out-growths of cell masses occur by the formation of special "leader" cells at the tops of outgrowths and "follower" cells along the sides. Leader cells exhibit profound cytoskeletal reorganization, including disassembly of marginal bundles, the realignment of actin filament bundles, and penetration of microtubules into highly active lamellae. Additionally, cell-cell contacts acquire radial geometry indicative of increased contractile tension. Interestingly, leader cells acquire a cytoskeletal organization and motility typical of fibroblasts. IAR-2 cultures stably transfected with a dominant-negative mutant of RhoA or treated with Rho-kinase inhibitor Y-27632 transformed most edge cells into leader-like cells. Alternatively, transfection of cells with constitutively active RhoA suppressed formation of leaders. Thus, expansion of the epithelial sheet involves functional differentiation into two distinct types of edge cells. The transition between these two patterns is controlled by Rho activity, which in turn controls the dynamic distribution and activity of actin filament bundles, myosin II, and microtubules.

Mechanisms of polarization of the shape of fibroblasts and epitheliocytes: Separation of the roles of microtubules and Rho-dependent actin-myosin contractility.

Cultured fibroblasts possess a characteristic polarized phenotype manifested by an elongate cell body with an anterior lamella whose cell edge is divided into protrusion-forming and inactive zones. Disruption of the fibroblast microtubule cytoskeleton leads to an increase in Rho-dependent acto-myosin contractile activity and concomitant loss of structural polarity. The functional relationship of myosin-driven contractile activity to loss of fibroblast anterior-posterior polarity is unknown. To dissect the roles of microtubule assembly and of Rho-dependent contractility on structural polarization of cells, polarized fibroblasts and nonpolarized epitheliocytes were treated with the microtubule-depolymerizing drug, nocodazole, and/or the Rho kinase inhibitor, Y-27632. Fibroblasts incubated with Y-27632 increased their degree of polarization by developing a highly elongate cell body with multiple narrow processes extended from the edges of the cell. Treatment of fibroblasts with nocodazole, alone or in combination with Rho kinase inhibitor, produced discoid or polygonal cells having broad, flattened lamellae that did not form long lamellar extensions. Single cultured epitheliocytes of the IAR-2 line do not display anterior-posterior polarization. When treated with Y-27632, the cells acquired a polarized, elongate shape with narrow protrusions and wide lamellas. Nocodazole alone or in combination with Y-27632 did not change the discoid shape of epitheliocytes, however treatment with Y-27632 produced thinning of the lamellar cytoplasm. We conclude that microtubules provide the necessary framework for polarization of fibroblasts and epitheliocytes, whereas Rho-regulated contractility modulates the degree of polarization of fibroblasts and completely inhibits polarization in epitheliocytes.

Management of tick bites and early Lyme disease: a survey of Connecticut physicians.

Practice guidelines have been published for the treatment of Lyme disease (LD). These guidelines have been challenged as inadequate. Two common LD management problems are antibiotic prophylaxis of deer tick bites (deer ticks may carry Borrelia burgdorferi, the spirochete that causes LD) and antibiotic treatment of erythema migrans, the pathognomonic rash of LD. A 1-page questionnaire was sent to a 13% (573/4300) sample of Connecticut physicians to define how they treat deer tick bites and erythema migrans. Questionnaires were returned by 320 (56%) of 573 physicians. Questionnaires were analyzed for the 267 physicians who saw patients with LD. Seventy (26%) of the 267 surveyed physicians prescribed antibiotic prophylaxis for patients with tick bites. B burgdorferi serology was ordered by 31% of physicians for patients with tick bites. Most surveyed physicians treated erythema migrans with doxycycline or amoxicillin for a mean of 21 days. Serology was ordered by 49% of physicians for patients with erythema migrans. Most physicians did not use prophylaxis for patients with deer tick bites. In addition, most of the physicians surveyed followed established guidelines for treating patients with erythema migrans. However, many of the physicians surveyed do serologic testing for patients with tick bites and/or erythema migrans. Serologic testing for these patients is usually not necessary.

Contact interactions between epitheliocytes and fibroblasts: formation of heterotypic cadherin-containing adhesion sites is accompanied by local cytoskeletal reorganization.

Contact interactions between different cell types play a number of important roles in development, for example in cell sorting, tissue organization, and ordered migration of cells. The nature of such heterocellular interactions, in contrast to interactions between cells of the same type, remains largely unknown. In this report, we present experimental data examining the dynamics of heterocellular interactions between epitheliocytes and fibroblasts, which express different cadherin cell adhesion molecules and possess different actin cytoskeletal organizations. Our analysis revealed two striking features of heterocellular contact. First, the active free edge of an epitheliocyte reorganizes its actin cytoskeleton after making contact with a fibroblast. Upon contact with the leading edge of a fibroblast, epitheliocytes disassemble their marginal bundle of actin filaments and reassemble actin filaments into a geometric organization more typical of a fibroblast lamella. Second, epitheliocytes and fibroblasts form cell--cell adhesion structures that have an irregular organization and are associated with components of cell adhesion complexes. The structural organization of these adhesions is more closely related to the type of contacts formed between fibroblasts rather than to those between epitheliocytes. Heterotypic epithelio-fibroblastic contacts, like homotypic contacts between fibroblasts, are transient and do not lead to formation of stable contact interactions. We suggest that heterocellular contact interactions in culture may be regarded as models of how tissue systems consisting of epithelia and mesenchyme interact and become organized in vivo.

Periodic fever, aphthous stomatitis, pharyngitis, adenitis: a clinical review of a new syndrome.

Periodic fevers (fevers that occur predictably at fixed intervals) are unusual in infants and children. The classic periodic fever syndrome is cyclic neutropenia (neutropenia followed by infections and fever that recur every 21 days). A new periodic fever syndrome PFAPA (periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis) has been characterized over the past decade. PFAPA is defined clinically, because specific laboratory abnormalities have not been found. The clinical characteristic of PFAPA is high fevers (usually 40.0 degrees C to 40.6 degrees C) recurring at fixed intervals every 2 to 8 weeks. The fevers last for about 4 days, then resolve spontaneously. Associated with the fevers are aphthous stomatitis in 70% of patients, pharyngitis in 72% of patients, and cervical adenitis in 88% of patients. PFAPA is not familial and begins before the age of 5 years. An episode of PFAPA can be aborted with one or two small doses of prednisone. The episodes of PFAPA may last for years and the patient is well between episodes. The cause of PFAPA is unknown and there are no reported sequelae.

Methicillin-resistant Staphylococcus aureus infections in 2 pediatric outpatients.

Methicillin-resistant Staphylococcus aureus (MRSA) infections are an emerging problem in children. The following are 2 case reports of unsuspected MRSA infections: the first is an infant with cervical adenitis and the second is a child with a deep infection of the toe. Both patients failed outpatient therapy with oral cephalosporins and required hospitalization for surgical drainage. Both patients had cultures positive for MRSA at surgery. Neither patient had any risk factors for acquiring MRSA. Thus, outpatients with presumed staphylococcal infections who fail oral therapy with cephalosporins may be infected with MRSA.

Immunogenicity of a recombinant Borrelia burgdorferi outer surface protein A vaccine against Lyme disease in children.

BACKGROUND AND OBJECTIVE: A recombinant lipoprotein vaccine against Lyme disease, containing 30 microg of Borrelia burgdorferi outer surface protein A (OspA) with aluminum adjuvant, has been shown in a large US field trial of subjects >/=15 years of age to offer 76% efficacy against clinical Lyme disease after 3 injections given at 0, 1, and 12 months. Lyme disease is also an important problem in children; thus, OspA vaccine trials in children are needed. The purpose of this study was to investigate the safety and immunogenicity of 2 different doses of lipoprotein OspA with aluminum adjuvant vaccine in healthy children 5 to 15 years of age in a double-blind, randomized study. STUDY DESIGN: In a double-blind study, 250 children from the Czech Republic were randomly assigned to receive 15 microg or 30 microg of OspA vaccine at 0, 1, and 2 months. Serum samples, obtained before vaccination and 1 month after the second and third doses, were analyzed for antiOspA antibody. Solicited and unsolicited symptoms were collected from diary cards. RESULTS: Local pain at the injection site was reported by approximately 76% of the 250 children. Headaches (after 5% to 18% of the injections) and malaise (after 2% to 16% of the injections) were the most frequently reported general symptoms. Local and generalized symptoms were not different between the 15 microg and 30 microg groups, and all symptoms resolved within 4 days. Both doses were highly immunogenic, with the 30 microg dose eliciting higher antibody levels. Seroconversion occurred in 99% of the 250 children. CONCLUSIONS: The OspA vaccine against Lyme disease was well tolerated and highly immunogenic in children.

Myosin-dependent contractile activity of the actin cytoskeleton modulates the spatial organization of cell-cell contacts in cultured epitheliocytes.

The spatial organization of cell-cell adherens junctions is distinct in cultured cells from two different tissue types, specifically, epitheliocytes and fibroblasts. In epitheliocytes, contacts are localized tangentially, along contacting cell edges and in association with circumferential actin bundles. Contacts between fibroblasts are radially oriented; that is, they are perpendicular to the overlapping edges of the cells and are associated with straight bundles of actin filaments. In the present study, we establish that the spatial organization of cell-cell contacts in the epithelial cell line IAR-2 can be converted from the typical tangential pattern to the radial pattern observed in fibroblasts. This transition can be induced by treatment with two agents, phorbol 12-myristate 13-acetate and nocodazole, which have different modes of action. Inhibition of myosin contractility reverses tangential-to-radial conversion of cell-cell contacts. These data suggest that formation of radially aligned contacts depends on modulation of contractility within the actin cytoskeleton through the myosin motor protein. The results open the possibility that modulation of the spatial organization of cell-cell contacts may play important roles in regulating organization and physiological functions of epithelial tissues.

Periodic fever syndrome in children.

OBJECTIVES: To describe the presentation, clinical course, therapeutic response, and long-term follow-up of patients with a syndrome of periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA). STUDY DESIGN: Patients with PFAPA (n = 94) referred over a 10-year period completed a registry form and provided medical records. Follow-up telephone calls were made in late 1997 to determine the persistence of episodes and sequelae. RESULTS: PFAPA episodes lasted 4.8 days (95% confidence interval 4.5 to 5.1) and recurred every 28 days (confidence interval 26 to 30), with a maximal temperature of 40.5 degrees C (confidence interval 40. 4 degrees to 40.6 degrees ). Of the 83 children available for follow-up, 34 no longer had episodes. In the remainder the episodes did not differ in character but recurred less frequently over time. The affected children had no long-term sequelae. Glucocorticoids were highly effective in controlling symptoms. Tonsillectomy and cimetidine treatment were associated with remission in a small number of patients. CONCLUSIONS: PFAPA is a not uncommon cause of periodic fever in children. In some children the syndrome resolves, whereas symptoms in others persist. Long-term sequelae do not develop. The syndrome is easily diagnosed when regularly recurring episodes of fever are associated with aphthous stomatitis, pharyngitis, or cervical adenitis.

Once-daily therapy for streptococcal pharyngitis with amoxicillin.

OBJECTIVE: An orally administered antimicrobial regimen for the treatment of group A beta-hemolytic streptococcal (GABHS) pharyngitis given once rather than multiple times each day would be more convenient and might result in improved patient compliance. The purpose of this study was to evaluate the effectiveness of once-daily amoxicillin in the treatment of GABHS pharyngitis. PATIENTS: Children presenting to a private pediatric office with GABHS pharyngitis. DESIGN: Patients were randomly assigned to receive orally either amoxicillin (750 mg once daily) or penicillin V (250 mg three times a day) for 10 days. Compliance was monitored by urine antimicrobial activity. OUTCOMES: Outcomes were measured by impact on the clinical course, eradication of GABHS within 18 to 24 hours, and bacteriologic treatment failure rate as determined by follow-up throat cultures 4 to 6 and 14 to 21 days after completing therapy. GABHS isolates were serotyped to distinguish bacteriologic treatment failures (same serotype as initial throat culture) from new acquisitions (different serotypes). RESULTS: During the 16 months of this study, 152 children between 4 and 18 years of age (mean, 9.9 years) were enrolled; 79 children were randomly assigned to receive once-daily amoxicillin and 73 were assigned to receive penicillin V three times a day. The children in the two treatment groups were comparable with respect to age, duration of illness before initiation of therapy, compliance, and signs and symptoms at presentation. There was no significant difference in the clinical or bacteriologic responses of the patients in the two treatment groups at the 18- to 24-hour follow-up visit. Bacteriologic treatment failures occurred in 4 (5%) of the 79 patients in the amoxicillin group and in 8 (11%) of the 73 patients in the penicillin V group. CONCLUSIONS: These data demonstrate that once-daily amoxicillin therapy is as effective as penicillin V therapy given three times a day for the treatment of GABHS pharyngitis, and if confirmed by additional investigations, once-daily amoxicillin therapy could become an alternative regimen for the treatment of this disease.

Rabies prophylaxis following the feeding of a rabid pony.

A survey was performed to identify people who were exposed to a rabid pony and determine whether or not they received rabies postexposure prophylaxis (PEP). Sixty-one visitors who came in contact with the rabid pony were identified. These visitors heard about the rabid pony via the news media. Forty-five visitors were exposed during the 2 weeks before the pony died. Thirty-two of these 45 visitors received PEP. Thirty-one visitors had or may have had saliva contact to an open wound or mucosa and all 31 received PEP. Fourteen visitors had no saliva contact to a wound or mucosa and one received PEP. Sixteen visitors were exposed before the pony was potentially shedding rabies virus and one received PEP. No visitor was bitten by the pony. Most of the persons 31/33 (94%) who received PEP had an exposure for which PEP was indicated. Nonbite transmission of rabies is discussed.