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BACKGROUND: Both nature exposure and green exercise (GE) provide numerous health benefits. However, there are no studies examining the impact of childhood GE on adult health. METHODS: 45 healthy adults (aged 69.8 ± 8.4 years) took part in the study, wearing a Firstbeat heart rate variability (HRV) monitor for 24 hours. Participants also completed questionnaires assessing childhood and adulthood nature exposure and GE, as well as current connectedness to nature (CN), perceived stress and well-being. Pearson's correlations and linear regression were used to examine relationships between variables. RESULTS: Childhood nature exposure and GE significantly predicted adult nature exposure and GE (ß .317, p < 0.05) as well as CN (ß = .831, p < 0.01). After controlling for childhood nature exposure and GE, CN was negatively associated with the percentage of stress over the 24-hour period (r = -.363; p < 0.05) and positively associated with HRV during sleep (r = .415; p < 0.05). CONCLUSIONS: CN is important for adult health; however childhood nature exposure and GE are essential to developing this connection.

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Biopsy of the superficial temporal artery is often used in the diagnosis of giant cell arteritis, but at traditional sites there is a risk of injury to the facial nerve. Recently the Gillies incision has been suggested as an alternative means of access for the biopsy, but the anatomical basis of this has not been fully elucidated. We therefore undertook a radiographic review of 150 patients, and examining 300 vessels, to find out. Our results indicated that there is considerable variability in the position of the bifurcation of the superficial temporal artery, and so a Gillies approach may not be reliable, particularly if access to the bifurcation is required.

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We fully characterize the reduced dynamics of an open quantum system initially correlated with its environment. Using a photonic qubit coupled to a simulated environment, we tomographically reconstruct a superchannel-a generalized channel that treats preparation procedures as inputs-from measurement of the system alone. We introduce novel quantitative measures for determining the strength of initial correlations, and to allow an experiment to be optimized in regard to its environment.

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Donor-π-acceptor photosensitizers for NiO photocathodes that exhibit a broad spectral response across the visible region are presented. These enabled an increase in the photocurrent density of p-type dye-sensitized solar cells to 8.2 mA cm(-2) and a tandem cell to be assembled which generated a photocurrent density of 5.15 mA cm(-2).

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BACKGROUND: Individuals with cystic fibrosis (CF) are deemed at risk of developing urinary incontinence (UI) due to repeated coughing and other factors causing increased pressure on the pelvic floor. Increased incidence of UI is recognised in women and increasingly in men and children. However, there is little comparison with normal controls and other respiratory conditions with chronic cough. Our aim was to report the incidence, degree and impact of UI in 9-16 year olds related to clinical status in CF, compared to these. METHODS: 9-16 year olds were invited to fill in a self-administered anonymous/confidential questionnaire at clinic. Data recorded were sex, age, height, weight, spirometry expressed as percentage predicted. Normal controls - age and sex only recorded. RESULTS: No significant differences were found between incidence of UI (21% CF; 22% respiratory; and 17% normal controls, P=0.43). No relationship found between respiratory or nutritional status and UI. Laughing, exercise and cough were the most common causes of UI. No difference between groups for age range, physiotherapy, breathlessness, antibiotics, urinary tract infections and menarche. Only 6% reported more than a few drops of UI. CONCLUSION: Incidence of urinary incontinence is no different between 9-16 year old girls and boys with CF, and controls.

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BACKGROUND: Bowel preparation is an important part of computed tomographic colonography (CTC); we evaluated two small-volume preparations for screening CTC with regard to quality of preparation and patient acceptability. METHODS: Asymptomatic subjects at average risk for colorectal cancer from a community-based CTC screening program were randomized to bowel preparation comprising magnesium/bisacodyl/picolax or polyethylene glycol (PEG)/picolax. CTC images were evaluated by a blinded investigator for residual feces and fluid; subjects completed a questionnaire regarding acceptability of the preparation. RESULTS: In 176 subjects randomized to magnesium/bisacodyl/picolax (n = 82) or PEG/picolax (n = 94), the former preparation was discontinued because of syncope or presyncope in four (5%) subjects. Another 137 subjects received PEG/picolax without a significant adverse event. There were no other major differences in acceptability of the preparations as reported by subjects. The quality of bowel preparations for reporting CTC was similar. CONCLUSION: For subjects having screening CTC, both small-volume bowel preparations are generally well tolerated and result in minimal fluid and fecal residue; however, the magnesium/bisacodyl/picolax preparation was accompanied by an unacceptable incidence of syncope and is no longer used by us.

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OBJECTIVE: Virtual colonoscopy (VC) is an evolving technology proposed as a possible screening tool for colorectal cancer. In contrast to conventional colonoscopy, VC may detect extracolonic abdominal pathology. This may lead to unnecessary investigation of benign lesions, or may benefit the patient by identifying serious pathology at an early stage. The aim of this study was to assess the prevalence and characteristics of extracolonic pathology found in patients undergoing VC. METHODS: A total of 100 patients aged > or = 55 yr, referred for colonoscopy for bowel symptoms or family history of bowel cancer, underwent VC. Axial views of the abdomen were reviewed prospectively by a single radiologist for extracolonic pathology. Patients with extracolonic abnormalities were referred to their local doctor or to a specialist clinic when appropriate. Case records were reviewed and treating doctors contacted to document subsequent investigations and procedures generated. RESULTS: Fifteen patients (15%) had extracolonic abnormalities detected. In four patients, the pathology had been diagnosed previously (umbilical hernia, gallbladder and renal calculi, 3.5-cm aortic aneurysm, ovarian cyst). Eleven patients had new abnormalities detected: ovarian cysts (three), liver cysts (two), uterine fibroids (two), gallstones (one), splenic calcifications (one), aortic aneurysm (one), and renal tumor (one). Two patients with ovarian cysts underwent surgery, and histology showed benign cysts. CONCLUSIONS: Extracolonic abnormalities are common at VC. Most are benign, but may lead to investigative and procedural costs. These data should be carefully evaluated in feasibility and cost-effectiveness studies on colorectal cancer screening using VC.

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AIM: To determine the accuracy of computed tomography colography (virtual colonoscopy) in detecting colorectal polyps and colorectal cancer. DESIGN: Blinded comparison of virtual colonoscopy (initially supine-only scans and later supine plus prone scans) with the criterion standard of conventional colonoscopy. SUBJECTS AND SETTING: 100 patients aged 55 years or over referred to a public teaching hospital for colonoscopy, July 1997 to January 2000, because of colonic symptoms or a family history of bowel cancer. MAIN OUTCOME MEASURES: Presence and size of polyps and other lesions; certainty of polyp identification on virtual colonoscopy (on 100-point visual analogue scale); sensitivity and predictive values of virtual colonoscopy. RESULTS: Conventional colonoscopy identifed 121 polyps in 47 patients; 28 of these polyps, in 19 patients, were identified by virtual colonoscopy. Sensitivity of virtual colonoscopy for detecting polyps (using supine plus prone scans) was 73% for polyps with diameter > or = 10 mm (95% CI, 39%-94%) and 19% for smaller polyps (95% CI, 10%-31%) (P < 0.001); corresponding figures for supine-only scans were 57% (95% CI, 18%-90%) and 11% (95% CI, 4%-24%), respectively. Ten polyps identified at virtual colonoscopy were considered false-positive findings (8%). The value of finding a polyp on virtual colonoscopy (with thresholds of 5 mm for diameter and 30 points for certainty score) was assessed as a predictor of finding a polyp (diameter > 5 mm) on conventional colonoscopy. Positive and negative predictive values were 88% and 89%, respectively, for supine plus prone scans. CONCLUSION: Although virtual colonoscopy shows potential as a diagnostic tool for colorectal neoplasia, it is currently not sufficiently sensitive for widespread use.

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The omega-atracotoxins are a family of 36 to 37-residue peptide neurotoxins that block insect but not mammalian voltage-gated calcium channels. The high phylogenetic specificity of these toxins recommends them as lead compounds for targeting insects that have developed resistance to chemical pesticides. We have begun to examine structure-function relationships in the omega-atracotoxins in order to explore the molecular basis of their activity and phylogenetic specificity. By probing the venom of the Blue Mountains funnel-web spider, Hadronyche versuta, for insecticidal toxins with masses close to that of omega-atracotoxin-Hv1a (omega-ACTX-Hv1a), we have isolated and sequenced five additional omega-atracotoxins. Five of the six omega-atracotoxins isolated from the venom of H. versuta (omega-ACTX-Hv1a to -Hv1e) differ from one another by only 1-3 residues and have similar insecticidal potencies. In contrast, omega-ACTX-Hv1f differs from the other toxins by up to 10 residues and it has markedly reduced insecticidal potency, thus providing information on key functional residues. The new atracotoxin sequences have revealed that the three N-terminal residues are highly conserved. Despite the fact that these residues are structurally disordered in solution we show here, by a series of N-terminal truncations, that they contribute significantly to insecticidal potency. However, loss of activity does not correlate with deletion of highly conserved residues, which leads us to propose that the disposition of the N-terminal charge, rather than the chemical properties of the N-terminal residues themselves, may be critical for the activity of omega-atracotoxin on insect calcium channels.

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The mechanism of human T-lymphocyte activation by the pathogenic yeast Cryptococcus neoformans has not been established. Previous investigations have suggested that C. neoformans contains a mitogen for T lymphocytes, while other investigators have attributed lymphocyte proliferation in vitro to a recall antigen. Because of the potential importance of the mechanism of T-cell activation for our understanding of the immune response to C. neoformans, the present studies were performed to determine whether C. neoformans contains a mitogen for T lymphocytes. C. neoformans stimulates fetal blood lymphocytes to proliferate and stimulates proliferation of CD45RA+ cells from adults, indicating that it stimulates naive T cells. The T-cell response to C. neoformans was dependent upon the presence of accessory cells. However, allogeneic cells were sufficient for accessory cell function, indicating that the response was not major histocompatibility complex restricted. The percentage of T cells in the cell cycle was higher than that with the recall antigen tetanus toxoid but lower than that with the mitogenic lectin phytohemagglutinin A or the superantigen Staphylococcus enterotoxin B. Precursor frequency analysis established that 1 in 7,750 +/- 2, 270 T cells proliferated in response to the cryptococcal cell wall and membrane. Compared to the case for most mitogens or superantigens, the proliferative response is late and the number of T cells that enter the cell cycle and the precursor frequency are low, indicating that the mitogenic effect is modest. However, the mitogenic effect of C. neoformans should be considered when interpreting the immune response to C. neoformans, since even weak mitogens can have profound effects on host defense.

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This paper describes a nondestructive method for distinguishing root flexibility from stem flexibility in living trees. It is used here for Sitka spruce (Picea sitchensis (Bong.) Carrière.), but is applicable to any species where the main stem is normally straight and near-vertical. Well-known engineering equations permit the calculation of deflected shape for a vertical cantilever with arbitrary distribution of mass and bending stiffness, when infjected to a lateral force. The equations are used to calculate stem deflections of four Sitka spruce trees for which the stem and branch mass distribution and stem taper have been measured. Free parameters in the mathematical model are a nominal value of Young's Modulus E (assumed uniform and isotropic over the cross section and height of the tree stem) and a root-anchorage stiffness k. The former allows the stem to curve, whereas the latter represents the flexibility of the roots and allows the stem to tilt elastically at ground level. For each of the four trees, the calculated deflection curve is compared with actual deflections measured when the living tree is pulled by a rope at a specified point. By adjusting both E and k, iteratively, a best fit solution is obtained. This provides a simple and effective way to determine both stem stiffness and root hinge stiffness from a single experiment on a living tree.

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Most literature describes endotracheal suction as a hazardous procedure associated with numerous complications and proposes that it should only be performed as necessary to minimize these complications. Other authors suggest endotracheal suction only after assessment predisposes patients to a number of different complications. This article describes a controlled study to compare and contrast the differences in endotracheal suction outcomes in patients who received ritualized 2 hourly suctioning and those who received it following assessment. A group of qualified nurses in an Intensive Care Unit were taught auscultation skills to assess a patient's needs for suctioning and all the nurses received educational training regarding endotracheal suctioning. Short-term ventilated patients were allocated to receive endotracheal suctioning either when the need for it was determined by assessment only or routinely, using a standardized suctioning technique. The results demonstrated a clear increase in nurses' knowledge regarding endotracheal suctioning. The assessed group of patients demonstrated significantly better outcomes and less complications than the controlled group in relation to changes in peak airway pressures, heart rate and mean arterial pressure pre- and post-endotracheal suctioning, and the amount of secretions obtained on suctioning. Although only preliminary, these results do provide support for the view that endotracheal suction only in response to assessment is better practice for short-term ventilated patients.

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Endotracheal suctioning (ETS) is a necessary practice carried out in intensive care units. In involves the removal of pulmonary secretions from a patient with an artificial airway in place. All intensive care nurses should be aware when performing this intervention of the potential hazards a patient is exposed to, and should endeavour to prevent or minimize these. This literature review explores the criteria available to indicate a need for ETS and discusses the potential adverse effects of ETS and how these can be avoided during the procedure. The question is raised as to the frequency with which the procedure should be performed. The current dilemma facing nurses is the overwhelming view that ETS should be performed only when indicated as necessary by assessment, to minimize the exposure of the patient to the hazards of ETS, but also recognition that ETS is a necessary procedure to maintain a patent airway and clear secretions. As nurses are accountable for all aspects of their practice, they need to be able to make an informed choice about the frequency with which ETS is performed. It is hoped that this review will increase nurses' awareness of the potential hazards surrounding ETS, and enable them to question their practices regarding their ability to assess individual patient needs and determine the frequency with which ETS should be performed.

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A newly described cytokine, interleukin (IL)-15, shares many activities with IL-2; however, little is known about the stimuli for release of IL-15, and its role in antimicrobial host defense has not previously been demonstrated. This study found that Cryptococcus neoformans is a potent stimulus for the release of biologically active IL-15 from monocytes. Both IL-15 and IL-2 made significant contributions to lymphocyte proliferation and lymphocyte-mediated anticryptococcal activity to encapsulated and acapsular C. neoformans. IL-15 restored lymphocyte proliferation and anticryptococcal activity that had been abrogated by blocking IL-2. IL-15 also enhanced the anticryptococcal activity of lymphocytes but did not enhance the activity of monocytes. This suggests that IL-15 and IL-2 cooperate for lymphocyte activation and proliferation in vitro and demonstrates that IL-15 can induce antimicrobial activity. Taken together, these data suggest that microbes, and in particular C. neoformans, are an important stimulus for IL-15 and that IL-15 may have an important role in induction of antimicrobial effector mechanisms.

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The current studies were performed to determine the contribution of T-cell subsets to lymphocyte proliferation in response to Cryptococcus neoformans, the most common invasive mycosis in acquired immune deficiency syndrome. We demonstrate for the first time that both human CD4 and CD8 cells are activated in response to C. neoformans. Both CD4 and CD8 cells express interleukin-2 receptor alpha (IL-2R alpha) and transferrin receptor and proliferate in response to C, neoformans, however proliferation of CD8 cells was dependent upon CD4 cells. The requirement for CD4 cells was complex, since CD8 enriched cells failed to express mRNA for IL-2, suggesting that CD4-dependent IL-2 production was required for CD8-cell proliferation. However, IL-2 was not sufficient to restore CD8-cell proliferation. These studies provide experimental evidence in humans to support the clinical impression that CD4 cells are important in cryptococcosis, and suggest that the appropriate CD4-derived signals could allow CD8 cells to assist in host defence.

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Cryptococcus neoformans is an encapsulated yeast that infects patients who have defective cell-mediated immunity, including AIDS, but rarely infects individuals who have intact cell-mediated immunity. Studies of the immune response to C. neoformans have been hampered by a paucity of defined T-lymphocyte antigens, and hence, the understanding of the T-cell response is incomplete. The goal of this study was to separate C. neoformans into its component parts, determine whether those components stimulate lymphocyte proliferation, perform preliminary characterization of the proteins, and establish the potential mechanism of lymphocyte proliferation. The lymphocyte response to fungal culture medium, whole organisms, disrupted organisms, and the yeast intracellular fraction or cell wall and membrane was studied by determining thymidine incorporation and by determining the number of lymphocytes at various times after stimulation. The cell wall and membrane of C. neoformans stimulated lymphocyte proliferation, while the intracellular fraction and culture filtrate did not. The optimal response occurred on day 7 of incubation, with 4 x 10(5) peripheral blood mononuclear cells per well and with 13 microg of cryptococcal protein per ml. The number of lymphocytes increased with time in culture, indicating that thymidine incorporation was accompanied by proliferation. Proteinase K treatment of the cell wall and membrane abrogated lymphocyte proliferation, indicating that the molecule was a protein. [35S]methionine labeling, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and fluorography were performed to analyze the proteins contained in the cell wall and membrane, intracellular fraction, and culture filtrate. At least 18 discrete bands were resolved from the cell wall and membrane. Since a large percentage of healthy adults responded to the cryptococcal cell wall and membrane, a mitogenic effect was investigated by testing proliferation of fetal cord blood lymphocytes. The percentage of fetal samples that proliferated in response to the cell wall and membrane was similar to the percentage of fetal samples that proliferated in response to Staphylococcus enterotoxin B, a microbial mitogen. Thus, a protein in the cell wall and membrane of C. neoformans is a potent stimulant of lymphocyte proliferation and has mitogenic properties, which may have important implications for cell-mediated immunity to C. neoformans.

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An investigation was undertaken at a printing company into an apparently high prevalence of trace dipstick hematuria discovered during routine medical examinations. In both the printing employees (n = 225) and a control group (n = 118) from other industries, the prevalence of hematuria exceeded that described in most previous reports (31% and 25%, respectively, using the criterion of > 12 glomerular red cells or > 2 nonglomerular red cells/microliter of urine). No focus of abnormality was identified within the printing plant and no association was identified between reported exposure to potentially toxic substances and the degree of hematuria. An occupational hygiene inspection and medical follow-up of selected workers did not reveal any significant abnormalities. The limitations of available information concerning "normal" urinalysis results suggests that hematuria may not be a useful test for the screening of occupational groups at risk of bladder cancer.

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Continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis remains the most common complication of this form of renal replacement therapy and the potential causative organisms are many and varied. Campylobacter bacteria are unusual causes of peritonitis in CAPD patients and we report our experience with eight cases and review those cases reported in the literature. In many episodes, there is a strong association with acute enterocolitis, which may precede the onset of cloudy dialysate by many days. The method of spread of these organisms from the gastrointestinal tract to the peritoneal cavity remains speculative. Bacteremic transfer would appear the most likely route, although it is probable that no single mode of spread explains all episodes. The treatment of choice of Campylobacter peritonitis is with intraperitoneal aminoglycoside in combination with oral erythromycin. An awareness of the potential for Campylobacter to cause CAPD-associated peritonitis, particularly when diarrhea is a prominent feature, has resulted in this organism becoming increasingly isolated in our unit.

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Handedness among architects was determined by mail survey. Contrary to previous reports, no evidence was found of an excess of left-handers among a sample of 236 fully qualified male architects and 78 male architectural students. A second study examined whether the use of mail surveys systematically biases the returns of handedness questionnaires. For this, questionnaires were sent to 1,017 university students. No evidence was found for a bias amongst those who did and did not reply to the initial questionnaire. These results strengthen the findings of the first study.

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