Synaptojanin 1: localization on coated endocytic intermediates in nerve terminals and interaction of its 170 kDa isoform with Eps15

Synaptojanin 1 is an inositol 5-phosphatase with a putative role in clathrin-mediated endocytosis. Goal of this study was to provide new evidence for this hypothesis. We show that synaptojanin 1 is concentrated at clathrin-coated endocytic intermediates in nerve terminals. Furthermore, we report that synaptojanin-170, an alternatively spliced isoform of synaptojanin 1, binds Eps15, a clathrin coat-associated protein. Binding is mediated by the COOH-terminal region of synaptojanin-170 which we show here to be poorly conserved from rat to humans, but to contain in both species three asparagine-proline-phenylalanine (NPF) repeats. This motif has been found to be the core of the binding site for the EH domains of Eps15. Together with previous data, our results suggest that synaptojanin 1 can be recruited to clathrin-coated pits via a multiplicity of interactions.

Plant meristems: cell signalling keeps the balance

Genetic and molecular analysis in Arabidopsis has identified components of a putative cell signalling pathway that appears to regulate the balance between stem cell proliferation and fate specification in meristems.

Meeting patients' needs: quality care in a changing environment

Recent surveys of patients in New York and Cleveland, among other cities, indicate that there is substantial room for improvement in meeting patients' needs and preferences, particularly in the areas of emotional support, coordination of care, discharge preparation, and the involvement of family and friends. Hospitals are using a variety of techniques to improve patient care and organizational efficiency in this challenging environment. One prominent approach, reengineering, offers a means by which hospitals can integrate highly specialized departmental structures and functions by focusing on interdisciplinary teamwork and organizing the delivery of care around patients. Key elements of successful hospital reengineering efforts have included: - the involvement and commitment of senior management and other key stakeholders, particularly physicians, nurses, and union representatives; - investment in staff training and retraining, and the redesign of staff evaluation and compensation systems; - timely, unit-specific measures of patient satisfaction and the clinical quality of care; - consistent and frequent internal communication between staff and leadership; and - treatment that emphasizes communication among caregivers, patients, and their family members. Several basic issues need to be addressed if hospitals are to offer technically sophisticated medical care that is also responsive to their patients' personal needs, including: - variations among patients regarding the amount of information they want and need, and the amount of involvement they want in their care; - the means by which patients will get information about their medical care, and who will provide any additional support that may be needed by non-English-speaking or socioeconomically disadvantaged patients; and - the specific changes in medical practice and hospital processes that will promote the involvement of patients in their care.

Alteration of Chlamydia trachomatis biologic behavior in synovial membranes. Suppression of surface antigen production in reactive arthritis and Reiter's syndrome

OBJECTIVE

To investigate the biologic state of Chlamydia and its surface antigen expression in the synovial membranes of patients with Chlamydia-associated reactive arthritis/Reiter's syndrome (ReA/RS).

METHODS

Expression of chlamydial lipopolysaccharide (LPS), major outer membrane protein (MOMP), and elementary body (EB) antigens was studied by gold labeling immunoelectron microscopy on 6 synovial membrane and 2 synovial fluid (SF) pellet samples from 6 patients with Chlamydia-associated arthritis. The study findings were compared with 24-hour cultures of HeLa cells infected with Chlamydia trachomatis EB.

RESULTS

Persistent C trachomatis infection was found in all 6 synovial membrane samples from patients who had either early or chronic arthritis. The infection persisted despite antibiotic treatment, including a 1-month course of doxycycline therapy. Most persistent organisms were atypical reticulate bodies (RBs) found in both fibroblasts and macrophages. Specific, but weak, immunogold staining for all 3 antibodies was found on both intracellular RBs and extracellular EBs. In the SF samples, Chlamydia surface antigens were detected only in phagosomes containing degraded electron-dense materials.

CONCLUSION

The synovial membrane biopsies conducted in this study of Chlamydia-associated ReA/RS revealed atypical RBs with diminished MOMP and LPS expression. Such altered organisms may escape immune surveillance and contribute to disease chronicity; moreover, these organisms may be difficult to detect and treat in some ReA/RS patients.

phantastica: a gene required for dorsoventrality of leaves in Antirrhinum majus

To understand better the mechanisms that lead to dorsoventrality in the lateral organs of plants, mutants at the phantastica (phan) locus of Antirrhinum majus have been identified and characterised. The leaves, bracts and petal lobes of phan mutants show varying degrees of reduction in dorsal tissues, indicating that phan is required for establishing dorsal cell identity. Each phan mutant produces a variety of different leaf morphologies, but has a characteristic and relatively constant floral phenotype. In several different forms of phan mutant leaves and petal lobes, novel boundaries between dorsal and ventral cell types form ectopic axes of growth, suggesting that phan-dependent dorsal cell identity is required for lateral growth of the wild-type leaf and petal lobe. Comparisons between the development of wild-type and mutant petals or leaves reveal that phan acts early in development of these lateral organs. The possible role of the phan gene in evolution of different leaf forms is discussed.

Sex differences in the distribution of EEG frequencies during sleep: unipolar depressed outpatients

Sex differences in period-amplitude-analysed (PAA) sleep EEG activity were evaluated in 20 symptomatic, unmedicated, unipolar, depressed outpatients. 19/20 PAA measures showed significant gender main effects or interactions. Overall, depressed females showed a higher incidence and amplitude of fast frequency, beta activity than males, particularly in the right hemisphere. Moreover, gender effects were also evident in sleep-stage-independent analysis of PAA measures. These findings are in striking contrast to normal controls for whom only slow-frequency activity differentiates males from females. These findings suggest that sex differences are stronger in depressed patients than those observed in normals and that these effects are more pronounced than age-related changes in sleep EEG activity.

Genetic and cellular characteristics of bladder outlet obstruction

Urinary bladder outlet obstruction is a common medical problem. In order to understand the effects of outlet obstruction on bladder morphology, physiology, and pharmacology, several animal models of obstruction have been developed using a variety of species. Although there are marked differences in bladder size, capacity, compliance, physiology, and pharmacology among these species, responses to outlet obstruction have many common characteristics. This article will be separated into six areas: introduction, genetic factors mediating the response during the initial period of partial outlet obstruction and overdistension, cytostructural alterations that accompany compensated bladder function, alterations in innervation accompanying bladder hypertrophy secondary to partial outlet obstruction, alterations in calcium translocation during bladder hypertrophy, and metabolic factors involved in the response to partial outlet obstruction.

Inhibition of amine oxidase activity by derivatives that recognize imidazoline I2 sites

Nonadrenergic imidazoline binding sites (imidazoline I2 sites) have been described to be colocated with monoamine oxidase (MAO) in the mitochondrial fraction of various cell types. In the present work, the authors considered whether this colocation could be associated with a functional interplay. In rat liver membranes, [3H]-idazoxan binding to I2 receptors was competed for by naphazoline and idazoxan, which also shared a high affinity for alpha-2 adrenoceptors (alpha-2 ARs). The chemicals 2-n-heptylimidazoline (S 15430), 1-methyl-5-n-heptylimidazole (S 15674), 2-benzofuran-2-yl-imidazoline (RX 801077) and 2-(1,3-benzodioxanyl)-2-imidazoline (RX 821029) exhibited higher affinity for I2 receptors than for alpha-2 ARs. The most selective agent was S 15430 with a 150-fold higher affinity for liver I2 receptors than for adipocyte alpha-2 ARs. Moreover, [3H]-idazoxan binding was also competed for by several MAO inhibitors (MAOI) that are not imidazoline or guanidinium derivatives such as tranylcypromine, harmaline, clorgiline and pargyline. Rat liver MAO activity was not only inhibited by MAOIs but also by some imidazoline derivatives: cirazoline, naphazoline, S 15674, RX 801077 and RX 821029. Idazoxan had no effect on MAO activity; it neither inhibited MAO nor prevented the inhibition induced by other imidazolines or MAOIs. This suggested that the ligand recognition site of I2 receptors was distinct from the MAOI target site. Furthermore, some imidazolines inhibited the activity of bovine plasma amine oxidase, an enzyme that does not possess the same cofactor as MAO and is insensitive to harmaline or pargyline.(ABSTRACT TRUNCATED AT 250 WORDS)

Brisk walking and serum lipid and lipoprotein variables in previously sedentary women--effect of 12 weeks of regular brisk walking followed by 12 weeks of detraining

The purpose of this study was to examine the effectiveness of brisk walking as a means of improving endurance fitness and influencing serum lipid and lipoprotein variables in previously sedentary women. Walkers (n = 10, mean (s.e.m.) age 47.3(2.0) years) followed a programme of brisk walking (mean(s.e.m.) speed 1.76(0.03) m s-1) for 12 weeks, after which the training stimulus was withdrawn. Controls (n = 10, mean(s.e.m.) age 41.6(1.2) years) maintained their habitual sedentary lifestyle throughout. Endurance fitness was determined using laboratory measures of responses to treadmill walking. Serum lipid and lipoprotein variables were determined in venous blood (12-h fasted). Body fatness was assessed by anthropometry and dietary practice using the 7-day weighed food intake technique. Measurements were repeated after 12 and 24 weeks. Brisk walking resulted in a decrease in heart rate and blood lactate concentration during exercise, while detraining was accompanied by a reversal of these changes. Changes in body mass and the ratio of circumferences at the waist and hip did not differ between groups but the sum of four skinfolds decreased with brisk walking and increased with detraining. High density lipoprotein (HDL) and HDL2 cholesterol increased with walking and decreased with detraining but no between group changes (analysis of variance, P < 0.05) were found in other lipid and lipoprotein variables. These findings suggest that regular brisk walking can improve endurance fitness and increase HDL cholesterol concentration in sedentary women.

An outbreak of cryptosporidiosis from fresh-pressed apple cider

BACKGROUND

Recent waterborne outbreaks have established Cryptosporidium as an emerging enteric pathogen, but foodborne transmission has rarely been reported. In October 1993, an outbreak of cryptosporidiosis occurred among students and staff attending a 1-day school agricultural fair in central Maine.

DESIGN

Environmental/laboratory investigation and cohort study.

PARTICIPANTS

Attendees of the fair and their household members.

MAIN OUTCOME MEASURES

Clinical or laboratory-confirmed cryptosporidiosis. Clinical cryptosporidiosis was defined as 3 days of either diarrhea (three loose stools in a 24-hour period) or vomiting.

RESULTS

Surveys were completed for 611 (81%) of the estimated 759 fair attendees. Among attendees who completed the survey, there were 160 (26%) primary cases. Cryptosporidium oocysts were detected in the stools of 50 (89%) of 56 primary and secondary case patients tested. The median incubation period was 6 days (range, 10 hours to 13 days); the median duration of illness was 6 days (range, 1 to 16 days). Eighty-four percent of primary case patients had diarrhea and 82% had vomiting. Persons drinking apple cider that was hand pressed in the afternoon were at increased risk for cryptosporidiosis (154 [54%] of 284 exposed vs six [2%] of 292 unexposed; relative risk, 26; 95% confidence interval, 12 to 59). Cryptosporidium oocysts were detected in the apple cider, on the cider press, and in the stool specimen of a calf on the farm that supplied the apples. The secondary household transmission rate was 15% (53/353).

CONCLUSIONS

This is the first large cryptosporidiosis outbreak in which foodborne transmission has been documented. It underscores the need for agricultural producers to take measures to avoid contamination of foodstuffs with infectious agents common to the farm environment.

Community psychiatric nurse teams: intensive support versus generic care

BACKGROUND

This study evaluated whether a community psychiatric nurse (CPN) team providing a comprehensive aftercare service, using a case management approach, improves psychopathology and social functioning of the long-term mentally ill, and reduces hospital use compared with a generic CPN team.

METHOD

Patients suffering from severe and persistent mental health problems were randomised to intensive aftercare or generic care after referral to the CPN manager. Each group contained 41 patients who were assessed at baseline and at 6, 12 and 18 months by an independent research psychologist. Outcome measures included the GAS, PSE, SAS, patient and relatives' satisfaction, number of admissions, and length of stay.

RESULTS

No difference between the groups was found on any of the outcome measures, despite the much higher number of contacts of the intensive (n = 52) versus generic CPNs (n = 13) and the much greater range of interventions.

CONCLUSIONS

Intensive aftercare for people with persistent mental health problems was not found to be of greater benefit than generic CPN care. Many factors need to be considered for aftercare to be effective, including community resources, process of care, and staff training.

Olive: a key gene required for chlorophyll biosynthesis in Antirrhinum majus

Olive (oli) is a recessive nuclear mutation of Antirrhinum majus which reduces the level of chlorophyll pigmentation and affects the ultrastructure of chloroplasts. The oli-605 allele carries a Tam3 transposon insertion which has allowed the locus to be isolated. The oli gene encodes a large putative protein of 153 kDa which shows homology to the products of two bacterial genes necessary for tetrapyrrole-metal chelation during the synthesis of bacteriochlorophyll or cobyrinic acid. We therefore propose that the product of the oli gene is necessary for a key step of chlorophyll synthesis: the chelation of magnesium by protoporphyrin IX. Somatic reversion of the oli-605 allele produces chimeric plants which indicate that the oli gene functions cell-autonomously. Expression of oli is restricted to photosynthetic cells and repressed by light, suggesting that it may be involved in regulating the rate of chlorophyll synthesis in green tissues.

Brisk walking improves endurance fitness without changing body fatness in previously sedentary women

The purpose of this study was to examine the influence of brisk walking on endurance fitness and the amount and distribution of body fat in previously sedentary women. Twenty eight women [mean age (SEM): 44.9 (1.5) years] followed the walking programme for 1 year, whilst 16 acted as controls [age 44.4 (2.3) years]. Changes in endurance fitness were evaluated by measuring the oxygen uptake (VO2) at a reference blood lactate concentration of 2 mmol.l-1. Two 1.61-km field tests of walking were completed, one at maximal speed and one at a "brisk" speed, as well as a 1.61-km walk on a motorised treadmill. The amount and distribution of body fat was determined by hydrostatic weighing and anthropometry and energy intake was evaluated using the 7-day weighed food intake method. Walkers completed an average of 157 min.week-1 of brisk walking over the year. The following were increased in walkers, relative to controls: brisk walking speed [walkers 1.73 (0.05) m.s-1 vs 1.88 (0.07) m.s-1; controls 1.69 (0.05) m.s-1 vs 1.70 (0.05) m.s-1 at baseline and 12 months respectively, P < 0.01], maximal walking speed and VO2 at 2 mmol.l-1. In addition, brisk walking reduced heart rate and blood lactate concentration during stepping as well as during standard, submaximal treadmill walking. It did not modify either the amount or the distribution of body fat, despite an unchanged energy intake.

The acute effects of low-intensity exercise on plasma lipids in endurance-trained and untrained young adults

The acute effects of low-intensity exercise on plasma lipids were assessed in 22 healthy, normolipidaemic volunteers [mean age (SEM) 21.1 (0.2) years] of whom 11 were untrained and 11 endurance trained. Each subject walked for 2 h on a treadmill at a speed selected to elicit 30% [29.8 (3.9)%] of his or her maximal oxygen uptake. All subjects consumed a similar diet, i.e. 48% of energy from carbohydrate, for 2 days prior to the test. Pre-exercise, high-density lipoprotein (HDL) cholesterol concentration was higher in the trained group than in the untrained group [0.88 (0.06) mmol.l-1 vs 0.73 (0.09) mmol.l-1, P less than 0.05]. The walk elicited an increase in blood lactate concentration (P less than 0.01) but glucose homeostasis was well maintained by both groups. After 2 h of walking total cholesterol had increased by 13 (0.6)% (P less than 0.05). HDL cholesterol concentration increased by 17 (1.6)%, so that the ratio of total to HDL cholesterol was lower after the walk than pre-exercise (P less than 0.05). In the endurance-trained group HDL cholesterol concentration increased progressively, being 7.9 (2.4)% higher after 1 h and 19.7 (1.6)% higher after 2 h. A different response was evident in the untrained group where a rise after the 1st h [25.1 (2.3)%] was followed by a decrease towards pre-exercise values. These results show that one prolonged bout of low-intensity exercise modifies lipoprotein metabolism and hold out the interesting possibility that this response may differ in trained and untrained individuals.

Thyrotropin-releasing hormone selectively reverses lorazepam-induced sedation but not slowing of saccadic eye movements

To investigate preliminary reports that benzodiazepine-induced sedation may be reversed by thyrotropin-releasing hormone (TRH), we examined the effect of TRH or saline placebo on two variables which are sensitive to benzodiazepine agonists: changes in sedation and saccadic eye movements. Lorazepam 10 micrograms/kg i.v. increased self-ratings of sedation and reduced self-ratings of alertness and these changes were almost completely reversed by TRH. In contrast the slowing of saccadic eye movements by lorazepam was not reversed by TRH. The effects of TRH do not appear to be due to a direct antagonism at the benzodiazepine receptor, since flumazenil reverses changes in both variables. Moreover ligand binding studies reveal that TRH has very low affinity at this receptor. These clinical data provide the first demonstration that it is possible to distinguish between the effects of benzodiazepines on saccadic eye movements and psychological self-ratings.

Comparison between effects of interleukin-1 alpha administration and sublethal endotoxemia in primates

Interleukin (IL)-1 is an early mediator of host response to inflammation, although its contribution to individual components of the acute phase reaction is still unclear. To evaluate how the hemodynamic, metabolic, and hormonal responses to sublethal endotoxemia compare with IL-1 administration, baboons received intravenously either lipopolysaccharide (LPS) or 0.1, 10, or 100 micrograms/kg IL-1 alpha. LPS induced an early tachycardia and a fall in mean arterial pressure, as well as lacticacidemia and hypoaminoacidemia. Similar hemodynamic and metabolic changes were seen with 10 or 100 micrograms/kg of IL-1 alpha. An increase in adrenocorticotropic hormone and fall in serum iron were induced by IL-1 alpha but not by LPS. Plasma tumor necrosis factor-alpha (TNF-alpha) was not measurable after IL-1 alpha administration, whereas LPS induced a monophasic TNF-alpha response. IL-6 levels were significantly greater after LPS than IL-1 alpha administration. Histopathological lesions, similar in LPS- and 100 micrograms/kg IL-1 alpha-treated groups, were present only in the adrenal cortex. We conclude that many, but not all, of the effects of sublethal endotoxemia can be replicated by IL-1 alpha administration, and these responses are dose dependent.

The efficacy of six heel pressure reducing devices

Twenty to 90 percent of pressure ulcers are located on the heel. The purpose of this study was to evaluate the pressure exerted on the heel when the foot in both the supine and the 30 degree elevated position was placed in various heel pressure reducing devices. Interface pressures of six heel devices were measured to determine their performance. Other factors, such as body weight, height shoe size, shoe width, as well as whether the device provided leg support were examined.