Micro-spectrometer for fusion plasma boundary measurements.

In situ probes are being developed to make direct, spatially resolved measurements of the ion energy spectra in the edge of tokamak plasmas while being easily replaced and requiring minimal resources. The ion spectrometers will consist of a combined collimator and energy analyzer fabricated from silicon and mated to a detector to yield a form factor of approximately 2.0 cm × 1.5 cm × 0.2 cm. Results of fabrication and testing of the combined collimator and energy analyzer element are presented.

Stevens-Johnson syndrome and toxic epidermal necrolysis at the University Hospital of the West Indies, Jamaica.

OBJECTIVE: Stevens-Johnson syndrome and toxic epidermal necrolysis are uncommon acute dermatologic disorders. The purpose of this study was to examine the frequency, aetiology and outcome of cases of Stevens-Johnson syndrome and toxic epidermal necrolysis admitted to the dermatology ward at the University Hospital of the West Indies. METHODS: This was a retrospective study looking at all patients who were admitted with a diagnosis of Stevens-Johnson syndrome, Stevens-Johnson syndrome/toxic epidermal necrolysis overlap syndrome and toxic epidermal necrolysis over a nine-year period. RESULTS: The results showed almost equal numbers of males and females. The drugs most commonly implicated were phenytoin and cotrimoxazole. The most common complications were hepatic impairment and ophthalmic complications. CONCLUSION: Stevens-Johnson syndrome and toxic epidermal necrolysis contribute significantly to morbidity and mortality of patients on the dermatology ward although mortality was low compared to other studies.

The effect of antenatal factors and postnatal growth on serum adiponectin levels in children.

Low levels of serum adiponectin (i.e. hypoadiponectinaemia) are a marker of cardiometabolic risk in overweight children. It is not clear whether early-life factors may play a role in the development of hypoadiponectinaemia. We investigated whether antenatal factors and postnatal growth are associated with childhood adiponectin levels. This was an observational study in a birth cohort (Vulnerable Windows Cohort Study). Anthropometry was measured at birth, at 6 weeks, every 3 months up to 2 years and then every 6 months. Fasting glucose, insulin, lipids and adiponectin were measured at a mean age 11.5 years. Data on 323 children were analysed with age- and sex-adjusted multivariate analyses. The sizes of mother, placenta, fetus and newborn were not significantly associated with adiponectin levels. Current weight, body mass index (BMI), fat mass, waist circumference, glucose, insulin resistance [homeostasis model assessment of insulin resistance (HOMA-IR)], triglycerides and systolic blood pressure were inversely related to adiponectin (P < 0.05). Faster growth in BMI during late infancy and childhood was associated with lower adiponectin levels (P < 0.05). After adjusting for current waist circumference, faster growth in BMI during early infancy was positively associated with adiponectin (P < 0.01). Faster growth in BMI during childhood was inversely associated (P < 0.001). These associations were similar after adjusting for HOMA-IR. We concluded that antenatal factors are not determinants of childhood adiponectin levels. Faster growth in BMI during infancy is associated with higher levels, whereas faster rates during childhood are associated with hypoadiponectinaemia. Hypoadiponectinaemia is a marker of a more adverse cardiometabolic profile in Afro-Caribbean children.

Diagnostic performance of the beam emission spectroscopy system on the National Spherical Torus Experiment.

The beam emission spectroscopy system on the National Spherical Torus Experiment measures localized density fluctuations on the ion gyroscale. Optical sightlines provide core to edge radial coverage, and the sightlines are aligned to typical pitch angles to maximize cross-field spatial resolution. Sightline images are 2-3 cm, and point spread function calculations indicate image distortion from pitch angle misalignment and atomic state finite lifetimes is minor with a 15% increase in the image size. New generation photodetectors achieve photon noise limited measurements at frequencies up to 400 kHz with refrigerant cooling at -20 °C. Measurements near the pedestal show broadband turbulence up to 100 kHz, and poloidal correlation lengths are about 10 cm. Plasma turbulence signals can be 2-3 orders of magnitude above photon noise and amplifier thermal noise.

Decline in the rates of meticillin-resistant Staphylococcus aureus acquisition and bacteraemia in a general intensive care unit between 1996 and 2008.

Analysis of admission and weekly screening and other cultures for meticillin-resistant Staphylococcus aureus (MRSA) taken in the intensive care unit (ICU) demonstrated a 75% reduction in the estimated rate of acquisition of MRSA between 1996 and June 2008. Four periods were defined by three events: a new ICU (December 1997); addition of a two-bed bay (January 2001); and extra infection control measures in ICU and the hospital generally, including screening of all admissions (December 2006). In ICU, acquisition/1000 bed-days decreased promptly in each successive period, 49.0 (34.4-63.6), 28.3 (21.7-34.9), 19.3 (16.3-22.3) and 11.8 (7.3-16.3) respectively, and MRSA bacteraemias/1000 bed-days decreased between the last three periods, 7.6 (4.7-10.5), 3.7 (2.6-4.8) and 0.4 (0-2.9) with no change in the proportion colonised progressing to bacteraemia and a small increase in the rate of other bacteraemias. From December 2006 prevalence of MRSA in admissions to ICU from general wards decreased from 13.5% (11.6-15.4) to 6.4% (4.0-8.8) consequent upon a reduction in estimated pre-ICU acquisition rate from 26.0 (22.7-29.3) to 9.4 (6.0-12.8)/1000 bed-days. These results suggest that the improved environment of the new ICU and its extension and the recent changes in infection control each contributed to the observed reductions in MRSA acquisition and subsequent bacteraemia within ICU. Improved infection control in the hospital was associated with decreased acquisition of MRSA on the general wards.

Cutaneous drug reactions in patients admitted to the dermatology unit at the University Hospital of the West Indies, Kingston, Jamaica.

OBJECTIVE: Cutaneous reactions are among the most common adverse reactions to drugs. The purpose of this study is to examine the aetiology and outcome of cutaneous drug reactions among patients admitted to the Dermatology Ward at the University Hospital of the West Indies. SUBJECTS AND METHODS: This was a retrospective study looking at all patients who were admitted with a diagnosis of a cutaneous drug eruption from January 1, 1997 to December 31, 2005. Data included patient demographics, date of admission to hospital, duration of hospitalization and a detailed drug history including any previous episodes of drug sensitivity. All drugs reportedly ingested by the patients up to three months prior to their cutaneous reaction were documented and the period of time between drug ingestion and the appearance of skin lesions was also noted. Clinical diagnosis, co-morbidities, histopathological diagnosis, final outcome and all ensuing disabilities were noted. The data retrieved were collated and analyzed using SPSS 12.0. RESULTS: The results showed a female to male ratio of 2.2:1. The categories of drugs most commonly implicated were antimicrobials followed by anti-epileptic drugs and nonsteroidal anti-inflammatory drugs. The most common form of drug eruption requiring admission was the exanthematous drug eruption followed by erythema multiforme, toxic epidermal necrolysis and Stevens-Johnson syndrome. CONCLUSION: In general, the causative agents identified and the types of drug eruptions were similar to those found in previous studies. However the anti-epileptic drugs, phenytoin and carbamazepine, ranked among the most commonly implicated drugs which differ significantly from other studies.

Contribution of acquired meticillin-resistant Staphylococcus aureus bacteraemia to overall mortality in a general intensive care unit.

During a period of 11 years, 77 patients had meticillin-resistant Staphylococcus aureus (MRSA) bacteraemia > or =5 days after admission to the intensive care unit (ICU). Ten had no prior growth of MRSA, 13 had positive screens on admission and 54 initially tested negative for MRSA in ICU before positive blood culture. These 54 constituted 20.2% [95% confidence interval (CI): 15.6-25.0] of 267 who acquired MRSA > or =5 days after admission. Mortality among 77 patients with MRSA bacteraemia was 57.1% (46.0-68.2). Nineteen of these 77 patients with MRSA bacteraemia had growth of a second pathogen from blood. Those with only MRSA bacteraemia were each matched with five controls by diagnosis and initial Acute Physiological and Chronic Health Evaluation II score. Mortality was greater in bacteraemic patients [53.6% (40.5-66.7)] than in controls [31.8% (26.3-37.3)] [relative risk (RR) 1.69 (1.25-2.26), P < 0.01], implying an additional absolute mortality of 21.8% (8.0-40.1). Application of this estimate to all 77 patients suggests that ICU-acquired MRSA bacteraemia caused 17 (6-31) deaths, adding 0.3% (0.1-0.6) to the 30.1% hospital mortality of all admissions. Incidence of MRSA bacteraemia increased with length of stay, contributing an estimated 3.1% (1.1-5.7) towards 37.9% mortality of the 198 patients remaining > or =25 days. These data emphasise the importance of preventing initial MRSA colonisation/infection of long-stay patients.

Estimates of the rate of acquisition of bacteraemia and associated excess mortality in a general intensive care unit: a 10 year study.

During a period of 10 years, 293 of 4270 admissions to the general intensive care unit (ICU) at Medway Maritime Hospital had 356 bacteraemias due to one of 14 microorganisms. Incidence of bacteraemia was least on the third day after admission, significantly greater on the fifth day and stable thereafter. From the fifth day the acquisition rate was 18.9 (16.5-21.3)/1000 bed-days, lower in those with an initial Acute Physiological Assessment and Chronic Health Evaluation II score (APII) <18, or admitted from the emergency room. A total of 1395 patients with no positive cultures in the first four days stayed in ICU for >or=5 days, and 204 subsequently had one or more bacteraemias. Hospital mortality in these patients was 45.6% (38.8-52.4), greater than in those with similar APII but sterile cultures [relative risk (RR): 1.30 (1.04-1.63) and matched controls, RR: 1.33 (1.09-1.63)]. Observed mortality was greater than predicted only in bacteraemic patients [RR: 1.31 (1.03-1.67)]. ICU-acquired bacteraemia was associated with an approximate additional absolute mortality of 11% contributing 0.5% to the 29.9% hospital mortality of all ICU admissions, 1.6% to the 34.6% of those staying >or=5 days, and 5.6% to the 35.9% of those remaining >24 days.

The prevalence of mucocutaneous disorders among HIV-positive patients attending an out-patient clinic in Kingston, Jamaica.

OBJECTIVES: Skin disorders are thought to occur frequently in persons with HIV/AIDS. To our knowledge, there are no studies in the literature reporting on the spectrum and prevalence of skin disorders in HIV-positive patients in the Caribbean. This study focused on the prevalence and spectrum of skin disorders seen in a population of HIV-positive patients in Jamaica. METHODS: A 5-year retrospective study was conducted by reviewing the records of patients attending a HIV out-patient clinic at the University Hospital of the West Indies in Kingston, Jamaica. RESULTS: Two hundred and eighty-six (286) patients were included in the study. Skin and mucous membrane disorders were documented in 74% of the patients in this series. Inflammatory disorders comprised the largest category of skin disorders followed by fungal infections. The most frequently diagnosed dermatological disorders were papular prurigo, oral candidiasis, dermatophyte infections, herpes simplex infections and seborrhoeic dermatitis. Kaposi's sarcoma was rare. This pattern is similar to those reported from the African continent and other tropical countries. CONCLUSIONS: Dermatological disorders contribute significantly to the morbidity of HIV-positive patients and patterns of skin disorders are similar to those seen in other tropical settings.

Space and time in the plant cell wall: relationships between cell type, cell wall rheology and cell function.

BACKGROUND: The biomechanical behaviour of plant cells depends upon the material properties of their cell walls and, in many cases, it is necessary that these properties are quite specific. Additionally, physiological regulation may require that target cells responding to hormonal signals or environmental factors are able to modulate these characteristics. ARGUMENT: This paper uses a rheological analysis of creep of elongating sunflower (Helianthus annuus) sunflower hypocotyls to demonstrate that the mechanical behaviour of plant cell walls is complex and involves multiple layered processes that can be distinguished from one another by the time-scale over which they lead to a change in tissue dimensions, their sensitivity to pH and temperature, and their responses to changes in spatial arrangement of the cell wall brought about by treatment with high M(r) PEG. Furthermore, it appears possible to regulate individual rheological processes, with limited effect on others, in order to modulate growth without affecting tissue structural integrity. It is proposed that control of the water content of the cell wall and therefore the space between cell wall polymers may be one mechanism by which differential regulation of cell wall biomechanical properties is achieved. This hypothesis is supported by evidence showing that enzyme extracts from growing tissues can cause swelling in cell wall fragments in suspension. IMPLICATIONS: The physiological implications of this complexity are then considered for growing tissues, stomatal guard cells and abscission cells. It is noted that, in each circumstance, a different combination of mechanical properties is required and that differential regulation of properties affecting behaviour over different time-scales is often necessary.

Methicillin-resistant Staphylococcus aureus in a general intensive care unit.

Methicillin-resistant Staphylococcus aureus (MRSA) has presented special problems in intensive care units (ICUs) because of the difficulties in implementing infection control measures. The prevalence and rate of acquisition of MRSA were studied over thirty months in a nine-bed ICU. Nasal and groin swabs were taken on admission and then weekly, and other cultures as clinically indicated. Of 1361 admissions 119 were MRSA-positive on arrival. 21 cases had been identified before admission and the remainder were detected by screening; in 57 the positive result was known only after discharge. Of the 1242 admissions initially negative 68 acquired MRSA while in the ICU. The ICU had no known MRSA-positive patients on 185 (20.3%) of 914 days, the longest sequence being 17 days. Positive patients occupied 1387 (16.9%) of the 8226 available bed days. Length of stay predicted the risk of acquiring MRSA. Estimated from patients who completed each weekly screening cycle, the risk was 7.5% per week in the first week and 20.3% per week thereafter. The risk was not influenced by initial APACHE II score, the use of haemofiltration, or the number of MRSA-positive patients in the unit. The data suggest that a further 38 of those discharged between weekly screenings acquired MRSA, giving an incidence of 8.5%. MRSA was grown from blood in 17 patients, and from sputum in 53 (ICU-acquired in 18% and 47%). This study suggests that nearly 10% of admissions to a general ICU will be MRSA-positive, of whom only half will be identified before discharge. With standard prevention the risk of previously negative patients acquiring MRSA approximates to 1% per day in the first week and 3% per day thereafter, with nearly one-fifth progressing to bacteraemia; one-half will have MRSA in sputum. Patients with longer stays constitute a high-risk minority for whom additional measures such as decontamination with oropharyngeal and enteral vancomycin should be considered.

Treating premenstrual dysphoric disorder using serotonin agents.

Premenstrual syndrome (PMS) affects 20%-50% of all women. Premenstrual dysphoric disorder (PMDD), which can be conceptualized as a more severe variant of PMS, can affect 3%-9% of all women. Because a significant number of women suffer from premenstrual disorders and afflicted women may spend up to half the month suffering from symptoms, it is important to identify and provide effective treatment for such women. Historically, it has been difficult to distinguish premenstrual disorders from other depressive disorders, given the high comorbidity of the two disorders. Most studies attempt to remove this confounding factor by excluding women with concurrent depressive disorders. Despite the difficulties and limitations inherent in studying treatments for premenstrual disorders, most investigations support the use of serotonin agents in treating PMDD.

Identification of a surface on the beta-propeller protein RACK1 that interacts with the cAMP-specific phosphodiesterase PDE4D5.

A strategy of mutagenesis followed by yeast two-hybrid assay was used to determine the sites on the WD-repeat protein Receptor for Activated C Kinase 1 (RACK1) necessary for it to interact with the cAMP-specific phosphodiesterase isoform PDE4D5. Analysis of deletion mutations demonstrated that WD-repeats 5-7, inclusively, of RACK1 contained the major site for interaction with PDE4D5. A reverse two-hybrid screen focusing on WD-repeats 5-7 of RACK1 isolated 11 single amino acid mutations from within this region that blocked the interaction. The ability of these mutations to block the interaction was confirmed by "pull-down" assays using bacterially expressed glutathione-S-transferase (GST)-RACK1 and mammalian cell-expressed PDE4D5. A model of RACK1 structure, based on the structural similarity of RACK1 to other beta-propeller WD-repeat proteins, indicated that the majority of the amino acids identified by mutagenesis are clustered in a discrete surface of RACK1. We propose that this surface of RACK1 is the major site for its interaction with the unique amino-terminal region of PDE4D5.

Extensiometric determination of the rheological properties of the epidermis of growing tomato fruit.

This paper examines the rheological properties of the fruit epidermis of tomato (Lycopersicon esculentum L.). This research was conducted because previous work had demonstrated that the rate of tomato fruit growth is determined by the interaction of tissue pressure and epidermal properties. A constant-load (or 'creep') extensiometer was employed in these experiments and the results interpreted using a model which describes creep retardation using a limited number of rheological elements, one of which appears analogous to plant growth and is of similar magnitude to fruit growth rate in vivo. The effects of pH, applied force and boiling upon the individual components of the model have been examined and indicate that several elements are strongly pH-dependent and that this dependency is eliminated by boiling. These results suggest that enzyme activity (plausibly that of one or more expansins) reduces the viscosity of the cell wall over a wide range of time scales. Further consideration of the creep of tomato epidermis in terms of models developed to describe the behaviour of artificial polymers suggests that the types of molecular event described by each rheological element can tentatively be identified and that pH-dependent enzyme activity facilitates both conformer rotation and macromolecular movement within the plant cell wall. These interpretations ascribe considerable importance to the time scale over which creep occurs.

Regulation of leaf and fruit growth in plants growing in drying soil: exploitation of the plants' chemical signalling system and hydraulic architecture to increase the efficiency of water use in agriculture.

In this paper the nature of root-to-shoot signals in plants growing in drying soil is considered in the context of their commercial exploitation in tomato (Lycopersicon esculentum L.) and other crops. Recent findings are presented on the effects of partial root drying (PRD) in the production of a glasshouse tomato crop. These findings show how an understanding of both root-to-shoot signalling mechanisms and fruit hydraulic architecture may explain observed increases in fruit quality, the differential effects of PRD on vegetative and reproductive production and the incidence of blossom end rot. Evidence is provided to support the hypothesis that the success of PRD may lie, at least in part, in the relative chemical and hydraulic isolation of the tomato fruit.

Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women.

This study was conducted to investigate the effect of therapeutic estrogen on cytochrome P450 1A2-mediated metabolism in postmenopausal women using caffeine as a model substrate. Twelve healthy postmenopausal women underwent estrogen replacement therapy in the form of estradiol (Estrace). Estradiol was initiated at a dose of 0.5 mg a day and titrated to achieve a steady-state plasma concentration of 50 to 150 pg/ml. Caffeine metabolic ratios (CMR; paraxanthine/caffeine) were assessed both before and after 8 weeks of estrogen replacement. For the 12 subjects, there was a mean reduction in CMR of -29.2 +/- 25.0 (p = 0.0019). Consistent with previous results found in younger women, these results indicate that exogenous estrogen in older women may inhibit CYP1A2-mediated caffeine metabolism.

Comparison of commercial Amies transport systems with in-house Amies medium for recovery of Neisseria gonorrhoeae.

Microbiologists are still encumbered by the variable performance of Amies charcoal transport medium in recovery of Neisseria gonorrhoeae. The objective of this study was to evaluate and select a good quality commercial system to replace our in-house preparation. We adsorbed 0.1 ml of a suspension from 30 gonococcal isolates onto each swab type and replaced the swab into the transport medium. We plated the swabs to New York City medium at 0, 24, 48, 72, and 96 h. We compared the survival of each isolate in the commercial Amies transport systems with that in our in-house Amies transport medium. The best recovery was observed with Copan transport systems. Some systems are inadequate and unacceptable for culture of gonococci.