Overriding water table control on managed peatland greenhouse gas emissions.

Global peatlands store more carbon than is naturally present in the atmosphere1,2. However, many peatlands are under pressure from drainage-based agriculture, plantation development and fire, with the equivalent of around 3 per cent of all anthropogenic greenhouse gases emitted from drained peatland3-5. Efforts to curb such emissions are intensifying through the conservation of undrained peatlands and re-wetting of drained systems6. Here we report eddy covariance data for carbon dioxide from 16 locations and static chamber measurements for methane from 41 locations in the UK and Ireland. We combine these with published data from sites across all major peatland biomes. We find that the mean annual effective water table depth (WTDe; that is, the average depth of the aerated peat layer) overrides all other ecosystem- and management-related controls on greenhouse gas fluxes. We estimate that every 10 centimetres of reduction in WTDe could reduce the net warming impact of CO2 and CH4 emissions (100-year global warming potentials) by the equivalent of at least 3 tonnes of CO2 per hectare per year, until WTDe is less than 30 centimetres. Raising water levels further would continue to have a net cooling effect until WTDe is within 10 centimetres of the surface. Our results suggest that greenhouse gas emissions from peatlands drained for agriculture could be greatly reduced without necessarily halting their productive use. Halving WTDe in all drained agricultural peatlands, for example, could reduce emissions by the equivalent of over 1 per cent of global anthropogenic emissions.

A controlled evaluation of the effect of social prescribing programs on loneliness for adults in Queensland, Australia (protocol).

BACKGROUND: In social prescribing, link workers support individuals whose persistent health problems are exacerbated by loneliness by connecting them to community-based social activities. This approach is well established in the UK and is gaining attention in Australia. However, a major limitation of research to date has been a lack of theoretically informed and rigorous evaluations of social prescribing. We will address these points in this study, applying a social identity framework to examine the effects of group-based social prescribing (SP) activity compared to primary care treatment as usual (TAU). METHODS: Ninety participants experiencing loneliness recruited from primary care services and community centres across five sites in Southeast Queensland will be assigned to one of two conditions (SP, TAU) and assessed at two timepoints (baseline, + 8 weeks). Individuals will be aged 18 years and over, have sufficient English language skills to provide consent, and at the time of recruitment they will not be experiencing acute symptoms or social issues that require urgent intervention. Primary outcomes are loneliness, mental well-being, and health service use (total number of GP, hospital, and allied health visits in the past 3 months). Secondary outcomes will assess social group processes, including number of important social groups, new group identification, multiple identity compatibility, and group-based support and emotion regulation. DISCUSSION: This study will provide comprehensive data about the extent to which, and how, social prescribing to community-based group activities may help people to feel less lonely, more socially integrated, and healthy over the first 8 weeks. If effective, this social identity-informed model of social prescribing can be disseminated in communities across Australia. TRIAL REGISTRATION: ANZCTR, Registered 8 June 2022 - Retrospectively registered, https://www.anzctr.org.au/ACTRN12622000801718.aspx.

Isolated Ocular Relapse of Acute Myeloid Leukaemia Post Allogeneic Stem Cell Transplant.

We present a rare case of a 39-year-old female with extramedullary relapse of acute myeloid leukaemia (AML) isolated to the left eye 2 months post allogeneic haematopoietic stem cell transplant. She initially presented with painless left eye erythema, swelling, and visual impairment. Initial ophthalmology review revealed conjunctival chemosis, raised intraocular pressure, and serous retinal detachments. She was initially treated for suspected orbital cellulitis with intravenous antibiotic and antifungal therapy but clinically progressed so was then treated with intravenous corticosteroids. One week later, she progressed to angle-closure glaucoma with development of a hypopyon and an enlarging subconjunctival mass. She proceeded to urgent subconjunctival biopsy and drainage of subretinal fluid which confirmed extramedullary relapse of AML. Notably, further investigation found no evidence of bone marrow or central nervous system relapse. She proceeded to localized radiotherapy with gradual resolution of the subconjunctival mass and serous retinal detachment and was for consideration of donor lymphocyte infusions and azacitidine therapy; unfortunately, she developed respiratory sepsis and passed away despite maximal efforts. This case represents a rare and unusual presentation of isolated ocular extramedullary relapse of AML and emphasises the importance of early ophthalmology involvement and tissue biopsy when there is high clinical suspicion of the disease.

Low risk management intervention: Limited impact of remedial tillage on net ecosystem carbon balance at a commercial Miscanthus plantation.

Perennial bioenergy crops are a key tool in decarbonizing global energy systems, but to ensure the efficient use of land resources, it is essential that yields and crop longevity are maximized. Remedial shallow surface tillage is being explored in commercial Miscanthus plantations as an approach to reinvigorate older crops and to rectify poor establishment, improving yields. There are posited links, however, between tillage and losses in soil carbon (C) via increased ecosystem C fluxes to the atmosphere. As Miscanthus is utilized as an energy crop, changes in field C fluxes need to be assessed as part of the C balance of the crop. Here, for the first time, we quantify the C impacts of remedial tillage at a mature commercial Miscanthus plantation in Lincolnshire, United Kingdom. Net ecosystem C production based on eddy covariance flux observations and exported yield totalled 12.16 Mg C ha-1 over the 4.6 year period after tillage, showing the site functioned as a net sink for atmospheric carbon dioxide (CO2). There was no indication of negative tillage induced impacts on soil C stocks, with no difference 3 years post tillage in the surface (0-30 cm) or deep (0-70 cm) soil C stocks between the tilled Miscanthus field and an adjacent paired untilled Miscanthus field. Comparison to historic samples showed surface soil C stocks increased by 11.16 ± 3.91 Mg C ha-1 between pre (October 2011) and post tillage sampling (November 2016). Within the period of the study, however, the tillage did not result in the increased yields necessary to "pay back" the tillage induced yield loss. Rather the crop was effectively re-established, with progressive yield increases over the study period, mirroring expectations of newly planted sites. The overall impacts of remedial tillage will depend therefore, on the longer-term impacts on crop longevity and yields.

Neuroimaging findings in adolescent gaming disorder: a systematic review.

OBJECTIVES: Gaming disorder is a growing concern affecting adolescents, exacerbated by the impact of recent COVID-19 restrictions. The World Health Organization has recently included gaming disorder in the 11th International Classification of Diseases (ICD-11). However, there is still an ongoing debate about the validity and reliability of the proposed clinical criteria, despite growing neurobiological evidence in this cohort. Systematic reviews in this area have focused mainly on adults or mixed adult/adolescent populations. Therefore, this systematic review explored the neuroimaging literature in adolescents (under 18 years old) with gaming disorder. METHODS: Using PRISMA 2020 guidelines, 3288 primary studies were identified from PubMed, CINAHL Plus, PsycINFO and Web of Science. After applying inclusion and exclusion criteria (appropriate title, abstract, comparison group used within study, English-language, neuroimaging and mean age under 18), 24 studies were included in this review. RESULTS: Functional and structural brain alterations in adolescent gaming disorder were noted across several imaging modalities, including electroencephalogram (EEG), functional magnetic resonance imaging (fMRI) and structural magnetic resonance imaging (MRI). Compared with healthy controls, adolescents with gaming disorder demonstrated neurological changes comparable to substance addiction, namely impairments in emotional regulation, reward-seeking, inhibition and increased risky decision-making. Positive brain adaptations in the areas of visuospatial processing and memory were observed. CONCLUSIONS: A number of key brain regions are affected in adolescent gaming disorder. These findings can help clinicians understand adolescent presentations with gaming disorder from a neurobiological perspective. Future studies should focus on forming a robust neurobiological and clinical framework for adolescent gaming disorder.

Species selection determines carbon allocation and turnover in Miscanthus crops: Implications for biomass production and C sequestration.

Growing Miscanthus species and hybrids has received strong scientific and commercial support, with the majority of the carbon (C) modelling predictions having focused on the high-yield, sterile and noninvasive hybrid Miscanthus × giganteus. However, the potential of other species with contrasting phenotypic and physiological traits has been seldom explored. To better understand the mechanisms underlying C allocation dynamics in these bioenergy crops, we pulse-labelled (13CO2) intact plant-soil systems of Miscanthus × giganteus (GIG), Miscanthus sinensis (SIN) and Miscanthus lutarioriparius (LUT) and regularly analysed soil respiration, leaves, stems, rhizomes, roots and soils for up to 190 days until leaf senescence. A rapid isotopic enrichment of all three species was observed after 4 h, with the amount of 13C fixed into plant biomass being inversely related to their respective standing biomass prior to pulse-labelling (i.e., GIG < SIN < LUT). However, both GIG and LUT allocated more photoassimilates in the aboveground biomass (leaves+stems = 78 % and 74 %, respectively) than SIN, which transferred 30% of fixed 13C in its belowground biomass (rhizomes+roots). Although less fixed 13C was recovered from the soils (<1 %), both rhizospheric and bulk soils were signficantly more enriched under SIN and LUT than under GIG. Importantly, the soils under SIN emitted less CO2, which suggests it could be the best choice for reaching C neutrality. These results from this unique large-scale study indicate that careful species selection may hold the success for reaching net GHG mitigation.

Gully hotspot contribution to landscape methane (CH4) and carbon dioxide (CO2) fluxes in a northern peatland.

Peatlands are long term carbon catchments that sink atmospheric carbon dioxide (CO(2)) and source methane (CH(4)). In the uplands of the United Kingdom ombrotrophic blanket peatlands commonly exist within Calluna vulgaris (L.) dominated moorland ecosystems. These landscapes contain a range of topographical features that influence local hydrology, climate and plant community composition. In this study we examined the variation in ecosystem CO(2) respiration and net CH(4) fluxes from typical plant-soil systems in dendritic drainage gullies and adjacent blanket peat during the growing season. Typically, Eriophorum spp., Sphagnum spp. and mixed grasses occupied gullies while C. vulgaris dominated in adjacent blanket peat. Gross CO(2) respiration was highest in the areas of Eriophorum spp. (650+/-140 mg CO(2) m(-2) h(-1)) compared to those with Sphagnum spp. (338+/-49 mg CO(2) m(-2) h(-1)), mixed grasses (342+/-91 mg CO(2) m(-2) h(-1)) and C. vulgaris (174+/-63 mg CO(2) m(-2) h(-1)). Measurements of the net CH(4) flux showed higher fluxes from the Eriophorum spp (2.2+/-0.6 mg CH(4) m(-2) h(-1)) locations compared to the Sphagnum spp. (0.6+/-0.4 mg CH(4) m(-2) h(-1)), mixed grasses (0.1+/-0.1 mg CH(4) m(-2) h(-1)) and a negligible flux detected from C. vulgaris (0.0+/-0.0 mg CH(4) m(-2) h(-1)) locations. A GIS approach was applied to calculate the contribution of gullies to landscape scale greenhouse gas fluxes. Findings from the Moor House National Nature Reserve in the UK showed that although gullies occupied only 9.3% of the total land surface, gullies accounted for 95.8% and 21.6% of the peatland net CH(4) and CO(2) respiratory fluxes, respectively. The implication of these findings is that the relative contribution of characteristic gully systems need to be considered in estimates of landscape scale peatland greenhouse gas fluxes.

Eating disorder services for young people in Ireland: perspectives of service providers, service users and the general adolescent population.

OBJECTIVES: This paper illuminates how national eating disorder (ED) policy translates into day-to-day practice by exploring how ED services are experienced by those who deliver and use them. METHODS: A mixed-methods approach was used, which combined qualitative and quantitative techniques. The paper collates data from three studies: (i) an interview study exploring the lived experiences of young people with EDs (n=8), their parents (n=5) and their healthcare professionals (n=3); (ii) a national survey of health professionals' perspectives on existing ED services (n=171); (iii) a nationwide survey of secondary-school students' eating concerns and patterns of help-seeking (n=290). RESULTS: The qualitative interviews with young people and their parents revealed feelings of isolation and helplessness. Young people expressed interest in patient support groups, while parents desired greater support for the family unit. Parents were highly critical of available services, particularly in relation to access. These criticisms were echoed in the survey of healthcare professionals, who reported many barriers to delivering effective care. Clinicians were almost unanimous in calling for care pathways to be clarified via a standardised treatment protocol. The survey of adolescents indicated widespread reluctance to seek help regarding eating concerns: over one-third expressed concern about their own eating habits, but half of these had not divulged their concerns to anyone. Participants' preferred pathways of help-seeking revolved around family and friends, and adolescents were unsure about routes of access to professional support. CONCLUSIONS: The research demonstrates that many aspects of national ED policy have not been implemented in practice. The paper highlights specific gaps and suggests ways they can be redressed.

Direct isotopic evidence of biogenic methane production and efflux from beneath a temperate glacier.

The base of glaciers and ice sheets provide environments suitable for the production of methane. High pressure conditions beneath the impermeable 'cap' of overlying ice promote entrapment of methane reserves that can be released to the atmosphere during ice thinning and meltwater evacuation. However, contemporary glaciers and ice sheets are rarely accounted for as methane contributors through field measurements. Here, we present direct field-based evidence of methane production and release from beneath the Icelandic glacier Sólheimajökull, where geothermal activity creates sub-oxic conditions suited to methane production and preservation along the meltwater flow path. Methane production at the glacier bed (48 tonnes per day, or 39 mM CH4 m-2 day-1), and evasion to the atmosphere from the proglacial stream (41 tonnes per day, or 32 M CH4 m-2 day-1) indicates considerable production and release to the atmosphere during the summer melt season. Isotopic signatures (-60.2‰ to -7.6‰ for δ13CCH4 and -324.3‰ to +161.1‰ for DCH4), support a biogenic signature within waters emerging from the subglacial environment. Temperate glacial methane production and release may thus be a significant and hitherto unresolved contributor of a potent greenhouse gas to the atmosphere.

Stigma and treatment of eating disorders in Ireland: healthcare professionals' knowledge and attitudes.

OBJECTIVES: This study examines aspects of healthcare professionals' knowledge and attitudes about eating disorders (EDs), which might impede the effective detection or treatment of EDs in Ireland. METHODS: A total of 1,916 healthcare professionals were invited to participate in a web-based survey. Participants were randomly allocated to view one of five vignettes depicting a young person with symptoms consistent with anorexia nervosa, bulimia nervosa, binge-eating disorder, depression or type 1 diabetes. Study-specific questions examined participants' responses to the vignettes and ED knowledge and experience. RESULTS: In total, 171 clinicians responded (9% response rate). Participants had an average of 15.8 years of clinical experience (s.d.=9.2) and included psychiatrists, GPs, psychologists and counsellors. Although participants' knowledge of EDs was moderately good overall, responses showed poor recognition of the symptoms of EDs compared with depression [χ 2 (4, n=127)=20.17, p<0.001]. Participants viewed EDs as chronic disorders that primarily affected females. Participants believed that clinicians like working with patients with depression and diabetes more than with AN patients [F (4,101)=5.11, p=0.001]. Among the professionals surveyed, psychiatrists were the most knowledgeable about EDs [F (4,82)=9.18, p<0.001], and were more confident in their ability to diagnose and treat EDs than professionals of all other disciplines, except psychologists [F (4,85)=8.99, p<0.001]. Psychiatrists were also the most pessimistic about ED patients' long-term life prospects [χ 2 (4, n=65)=15.84, p=0.003]. CONCLUSIONS: This study recommends that specific attention should be given to EDs in professional educational programmes across healthcare disciplines. This training should not be restricted to improving healthcare professionals' knowledge of EDs, but should also strive to increase service-providers' awareness of how their own potentially stigmatising attitudes can undermine engagement with treatment.

Primary angioplasty for the treatment of acute myocardial infarction: experience at two community hospitals without cardiac surgery.

OBJECTIVES: We sought to establish the safety and efficacy of primary percutaneous transluminal coronary angioplasty in patients with acute myocardial infarction (AMI) at two community hospitals without on-site cardiac surgery. BACKGROUND: Though randomized studies indicate that primary angioplasty in AMI may result in superior outcomes compared with fibrinolytic therapy, the performance of primary angioplasty at hospitals without cardiac surgery is debated. METHODS: Three experienced operators performed 506 consecutive immediate coronary angiograms with primary angioplasty when appropriate in patients with suspected AMI at two community hospitals without cardiac surgery, following established rigorous program criteria. RESULTS: Clinical high risk predictors (Killip class 3 or 4, age > or = 75 years, anterior AMI, out-of-hospital ventricular fibrillation) and/or angiographic high risk predictors (left main or three-vessel disease or ejection fraction <45%) were present in 69.6%. Angioplasty was performed in 66.2%, with a median time from emergency department presentation to first angiogram of 94 min and a procedural success rate of 94.3%. The in-hospital mortality for the entire study population was 5.3%. Of those without initial cardiogenic shock, the in-hospital mortality was 3.0%. Of 300 patients who were discharged after primary angioplasty, only four died within the first 6 months, with 97.7% follow-up. No patient died or needed emergent aortocoronary bypass surgery because of new myocardial jeopardy caused by a complication of the cardiac catheterization or angioplasty procedure. CONCLUSIONS: Immediate coronary angiography with primary angioplasty when appropriate in patients with AMI can be performed safely and effectively in community hospitals without on-site cardiac surgery when rigorous program criteria are established.

Adolescents' and parents' views of Child and Adolescent Mental Health Services (CAMHS) in Ireland.

Service user involvement is essential for quality care in the Child and Adolescent Mental Health Services (CAMHS). This study was conducted to explore adolescents' and parents' experiences of CAMHS in relation to accessibility, approachability and appropriateness. This study used a descriptive qualitative design, and focus groups and single interviews were conducted with adolescents (n = 15) and parents (n = 32) from three mental health clinics. Data were analysed using thematic analysis. Accessing mental health services was a challenging experience for many parents and adolescents due to knowledge deficit, lack of information and limited availability of specialist services. Some parents and adolescents reported positive experiences while others reported negative experiences. They expressed a need for more information, involvement in decision making, flexible scheduling of appointments, school support and parent support groups. The nature and quality of the relationship with staff was critical to positive experience with the service; therefore, frequent changes of medical staff was disruptive. Mental health nurses can play a vital role in ensuring continuity, assessing adolescents' participation preferences and advocating for their information needs with other members of the interdisciplinary team.

Who is in the transition gap? Transition from CAMHS to AMHS in the Republic of Ireland.

OBJECTIVE: The ITRACK study explored the process and predictors of transition between Child and Adolescent Mental Health Services (CAMHS) and Adult Mental Health Services (AMHS) in the Republic of Ireland. METHOD: Following ethical approval, clinicians in each of Ireland's four Health Service Executive (HSE) areas were contacted, informed about the study and were invited to participate. Clinicians identified all cases who had reached the transition boundary (i.e. upper age limit for that CAMHS team) between January and December 2010. Data were collected on clinical and socio-demographic details and factors that informed the decision to refer or not refer to the AMHS, and case notes were scrutinised to ascertain the extent of information exchanged between services during transition. RESULTS: A total of 62 service users were identified as having crossed the transition boundary from nine CAMHS [HSE Dublin Mid-Leinster (n=40, 66%), HSE South (n=18, 30%), HSE West (n=2, 3%), HSE Dublin North (n=1, 2%)]. The most common diagnoses were attention deficit hyperactivity disorder (ADHD; n=19, 32%), mood disorders (n=16, 27%), psychosis (n=6, 10%) and eating disorders (n=5, 8%). Forty-seven (76%) of those identified were perceived by the CAMHS clinician to have an 'on-going mental health service need', and of these 15 (32%) were referred, 11 (23%) young people refused and 21 (45%) were not referred, with the majority (12, 57%) continuing with the CAMHS for more than a year beyond the transition boundary. Young people with psychosis were more likely to be referred [χ 2 (2, 46)=8.96, p=0.02], and those with ADHD were less likely to be referred [χ 2 (2, 45)=8.89, p=0.01]. Being prescribed medication was not associated with referral [χ 2 (2, 45)=4.515, p=0.11]. In referred cases (n=15), there was documented evidence of consent in two cases (13.3%), inferred in another four (26.7%) and documented preparation for transition in eight (53.3%). Excellent written communication (100%) was not supported by face-to-face planning meetings (n=2, 13.3%), joint appointments (n=1, 6.7%) or telephone conversations (n=1, 6.7%) between corresponding clinicians. CONCLUSIONS: Despite perceived on-going mental health (MH) service need, many young people are not being referred or are refusing referral to the AMHS, with those with ADHD being the most affected. CAMHS continue to offer on-going care past the transition boundary, which has resource implications. Further qualitative research is warranted to understand, in spite of perceived MH service need, the reason for non-referral by the CAMHS clinicians and refusal by the young person.

Prominent location of a K+ channel containing the alpha subunit Kv 1.2 in the basket cell nerve terminals of rat cerebellum.

A panel of monoclonal antibodies specific for a family of voltage-dependent, fast-activating K+ channels, raised against alpha-dendrotoxin acceptors purified from bovine brain, were used to probe the distribution of these important proteins in rat cerebellum. All the antibodies reacted with their antigens in the folial white matter, the granular cell layer and the basket cell nerve termini within the Purkinje cell layer. However, a very intense staining pattern was exhibited by only one monoclonal that reacts exclusively with Kv 1.2 alpha subunit, the predominant isoform present in alpha-dendrotoxin sensitive K+ channels. Double-labelling procedures with neuronal and glial markers were used to verify this discrete antibody staining of the basket cell terminals that synapse with the base of Purkinje cell bodies in a readily recognizable and characteristic fashion. This is the first direct demonstration, using a monoclonal antibody, of a presynaptic location for a voltage-activated K+ channel; its discrete distribution in the basket cell pinceau suggests that it could control release of the inhibitory transmitter GABA and, thereby, influence excitability of Purkinje cells in the cerebellum.

Stromal acidosis modulates corneal swelling.

PURPOSE: Studies have shown that stromal acidosis reduces the rate of corneal thickness recovery after induced edema, providing the first human in vivo evidence that corneal pH can influence corneal hydration control. This finding raises the question of the possible effect that pH may have on induced corneal swelling. To explore this question, the corneal swelling response to hypoxia was measured while stromal pH was controlled. METHODS: Corneal edema and stromal acidosis was induced in ten subjects by passing a mixture of nitrogen and carbon dioxide gas across the eyes through tight-fitting goggles. One eye of each subject received 100% N2, whereas the contralateral eye received a mixture of 95% N2 and 5% CO2. Exposures of 95% N2 + 5% CO2 lower pH on average to 7.16 versus 7.34 for 100% N2 alone. Before and after 2.5 hours of gas exposure, central corneal thickness (CCT) was measured. RESULTS: Eyes exposed to the lower pH environment (eg, N2 + CO2) developed less change in CCT compared to the eyes receiving N2 alone. Overall increase in CCT was 29.9 +/- 5.3 microns for eyes exposed to the 95% N2 + 5% CO2 gas mixture, versus 37.1 +/- 4.8 microns for 100% N2 eyes (P < 0.0001). CONCLUSIONS: The corneal swelling response to hypoxia can be reduced by lowering stromal pH. Because changes in corneal pH alone have not been found to alter steady-state CCT, it is proposed that pH exerts its effect only under non-steady-state conditions (ie, corneal swelling and deswelling). This suggests that acidosis may produce changes in the rate of lactate metabolism or alter endothelial hydraulic conductivity.

Measurement of corneal epithelial permeability to fluorescein. A repeatability study.

PURPOSE: Permeability (Pdc) to sodium fluorescein (F) is a characteristic of the barrier function of the corneal epithelium. The repeatability of several in vivo fluorophotometric methods used to measure permeability in humans remains largely undocumented. This study examines the repeatability of a method based on topical instillation of a single drop of F for the quantitative assessment of Pdc. METHODS: Nine healthy subjects with no history of ocular disease provided 1 (n = 1), 2 (n = 1), or 3 (n = 7) repeated measurements of each eye at successive visits. After making 3 baseline fluorescence scans centrally through the tear film and cornea, 2 microliters of 0.35% F were instilled and 10 fluorescence scans were obtained at approximately 2-minute intervals immediately after instillation. Subsequently, the eyes were rinsed three times with nonpreserved saline and four additional scans were performed. RESULTS: Pdc was calculated by dividing the baseline-corrected postrinse stromal fluorescence by the time integral of the tear film fluorescence calculated over the 20-minute exposure period. After applying a logarithmic transformation to the Pdc estimates, a mixed-model analysis was used to assess measurement repeatability. On the Pdc scale, there is an estimated 95% chance that a second measurement could be as much as 2.88 times higher or 0.35 times lower than a first measurement. CONCLUSIONS: This substantial variability between repeated measurements indicates that the single-drop procedure is unreliable for monitoring individual patient changes. However, with careful sample size planning, this technique can be used in population-based research to compare differences in treatment effects between groups of subjects.

Measurement of post-lens tear thickness.

PURPOSE: A method to measure the tear film beneath a soft contact lens, referred to as post-lens tear thickness (PLTT), would have many applications to contact lens research. In this study a noninvasive technique for measuring the PLTT is presented. METHODS: The feasibility of measuring the tear layer by optical pachometry was first assessed using a model eye. The baseline corneal thickness (B) of both eyes of 21 subjects was measured, etafilcon-A ionic disposable soft contact lenses (58% water) were inserted, and the total thickness (T) of the cornea, contact lens, and PLTT were measured. After the pachometry readings the lenses were removed and their center thickness (C) determined. The PLTT was calculated using the equation: PLTT = T-(B+C). Two sets of measurements of T were performed at 15 and 25 minutes after lens insertion. The entire procedure was repeated at a second visit. RESULTS: The pachometry measurements of the small aqueous reservoir between the model eye and the lens closely matched those obtained by direct microscopic measurement. For human PLTT, the mean values (and 95% confidence intervals) for right eyes on visits 1 and 2 were 11 (8, 13) and 12 (10, 15) microm, respectively, and for left eyes were 12 (10, 15) and 11 microm (8, 14) microm, respectively. CONCLUSIONS: It is possible to measure the post-lens tear thickness using optical pachometry. The variability between repeated measurements suggests that with careful sample size planning, the technique is sufficiently precise to be useful in group assessments of PLTT.

Corneal function during normal and high serum glucose levels in diabetes.

PURPOSE: To assess corneal structure and the effects of acute hyperglycemia on corneal function in subjects with type 1 diabetes. METHODS: Twenty-one diabetic and 21 nondiabetic volunteers of similar age were recruited. Baseline measurements of intraocular pressure (IOP), corneal thickness (CT), corneal autofluorescence (CAF), corneal sensitivity (CST), central and temporal endothelial cell density (DenC and DenT), and coefficient of variation in cell area (CVC and CVT) were taken. Corneal edema was induced, and the percent recovery per hour (PRPH) from hypoxic edema and endothelial permeability to fluorescein were determined. These procedures were done twice in the diabetic subjects under controlled euglycemic (EG) and hyperglycemic (HG) conditions, and once in control subjects while they were fasting. RESULTS: Substantial differences in baseline measurements were found for IOP, CT, CAF, CST, DenC, and CVT. The mean +/- SE corneal swelling in the HG diabetic subjects (51.6 +/- 2.3 microm) was less when compared to the swelling in the EG diabetic subjects (56.2 +/- 1.87 microm, P = 0.05) and the control subjects (58.9 +/- 1.56 microm, P = 0.011). During euglycemia, the mean +/- SE PRPH was less in diabetic subjects than in control subjects (65.0 +/- 3.20 versus 73.8 +/- 1.81%/hour, P = 0.02) but did not differ in diabetic subjects under EG and HG conditions (65.0 +/- 3.20 versus 67.7 +/- 3.1%/hour, P = 0.56). No significant differences were noted between groups in endothelial permeability. CONCLUSIONS: In addition to differences in baseline corneal structure, diabetic subjects showed less corneal swelling and reduced corneal recovery from hypoxia than did control subjects. During acute hyperglycemia, corneal swelling was less than during euglycemia in diabetic subjects, which suggests that hyperglycemia affected corneal hydration control.

Late angiographic follow-up after successful coronary arterial thrombolysis and angioplasty during acute myocardial infarction.

Emergency percutaneous transluminal coronary angioplasty (PTCA) is accepted as an important reperfusion intervention for acute myocardial infarction (AMI). Although its primary success rate is well documented, the frequency of restenosis after this procedure is unclear. The frequency of restenosis was determined in patients undergoing emergency PTCA at least 6 months after PTCA was performed during AMI. Of 66 consecutive patients undergoing emergency PTCA, 25 had a second, elective catheterization at an average of 22 months after AMI and 6 underwent repeat catheterization because of recurrent chest pain. Restenosis of the PTCA site was found in 10 of the 31 patients (32%) restudied. Also, 14 (45%) of these 31 patients showed progression of narrowing in the non-infarct-related coronary arteries. In summary, patients in whom AMI is treated by PTCA are at risk for restenosis and for progressive narrowing of the non-infarct artery.

A double-blind pilot study of risperidone in the treatment of conduct disorder.

OBJECTIVE: To examine whether risperidone is superior to placebo in the treatment of youths with conduct disorder. METHOD: This was a 10-week, randomized, double-blind, placebo-controlled study with 2 parallel arms. Ten youths were randomly assigned to receive placebo and 10 youths were randomly assigned to receive risperidone. Patients were seen weekly throughout the trial. Medications could be increased at weekly intervals during the first 6 weeks of the study from an initial dose of 0.25 mg or 0.50 mg each morning, depending on patient weight. Patients weighing less than 50 kg had a maximum total daily dose of risperidone of 1.5 mg. Patients weighing 50 kg or greater had a maximum total daily dose of risperidone of 3.0 mg. The primary outcome measure was the Rating of Aggression Against People and/or Property Scale. RESULTS: Risperidone was superior to placebo in ameliorating aggression on most measures. Risperidone was reasonably well tolerated, with none of the risperidone-treated patients developing extrapyramidal side effects. CONCLUSIONS: These data provide preliminary evidence that risperidone may have efficacy in the treatment of youths with conduct disorder. Because of the small sample size and the brief length of this study, further research is necessary to confirm these findings.