Benefitting productivity and the environment: Current and future maize cropping systems improve yield while reducing nitrate load

Increases in cereal crop yield per area have increased global food security. "Era" studies compare historical and modern crop varieties in controlled experimental settings and are routinely used to understand how advances in crop genetics and management affect crop yield. However, to date, no era study has explored how advances in maize (Zea mays L.) genetics and management (i.e., cropping systems) have affected environmental outcomes. Here, we developed a cropping systems era study in Iowa, USA, to examine how yield and nitrate losses have changed from "Old" systems common in the 1990s to "Current" systems common in the 2010s, and to "Future" systems projected to be common in the 2030s. We tested the following hypothesis: If maize yield and nitrogen use efficiency have improved over previous decades, Current and Future maize systems will have benefits to water quality compared to Old systems. We show that not only have maize yield and nitrogen use efficiency (kg grain kg-1 N), on average, improved over time but also yield-scaled nitrate load + soil nitrate was reduced by 74% and 91% from Old to Current and Future systems, respectively. Continuing these trajectories of improvement will be critical to meet the needs of a growing and more affluent population while reducing deleterious effects of agricultural systems on ecosystem services.

Music therapy for supporting informal carers of adults with life-threatening illness pre- and post-bereavement; a mixed-methods systematic review

BACKGROUND

Music therapy interventions with informal carers of individuals with life-threatening illness at pre- and post-bereavement is an increasingly important clinical area. This systematic review is the first to synthesise and critically evaluate the international evidence associated with music therapy with adult informal carers pre- and post-bereavement. Specifically, the objectives were: i) to describe the characteristics and effectiveness of music therapy interventions which aim to improve health-related outcomes for adult informal carers of adults with life-threatening illness (pre- and post-bereavement), and ii) to describe the experience of music therapy for adult informal carers of adults with life-threatening illness (pre- and post-bereavement).

METHODS

Eligibility: adult informal carers of adults at end of life or bereaved; music therapy interventions for improving health-related outcomes; qualitative; mixed-method; and quantitative studies including comparators of any other intervention; published in English from 1998 onwards. Six databases were searched up to July 2022. A JBI mixed-methods systematic review approach was followed throughout, including quality appraisal, data extraction and a convergent segregated approach to synthesis and integration.

RESULTS

A total of 34 studies were included, published between 2003 and 2022. Most were conducted in North America (n = 13), Australia (n = 10), or Europe (n = 8). No studies were conducted in low- and middle-income countries or in the UK. The majority were qualitative (n = 17), followed by quasi-experimental (n = 8), mixed-methods (n = 7) and two RCTs. The majority focused on carers of individuals with dementia (n = 21) or advanced cancer (n = 7). Seventeen studies were purely quantitative or included a quantitative component. During meta-synthesis, findings were aligned to core outcomes for evaluating bereavement interventions in palliative care and previously identified risk factors for complicated grief. Commonly targeted outcomes in quantitative studies included quality of life and mental wellbeing, showing equivocal effectiveness of music therapy with significant and non-significant results. Twenty-two studies either purely qualitative or with a qualitative component underwent meta synthesis and suggested a diverse range of improved pre- and post-bereavement outcomes for informal carers across all core outcomes, and across all risk and protective factors, including psychological, spiritual, emotional, and social outcomes.

CONCLUSIONS

Qualitative studies provide moderate to strong evidence for improved health-related outcomes for adult informal carers of adults with life-threatening illness pre-bereavement. Limited studies including those bereaved negates conclusions for the bereavement phase. Comparisons and explanations for effectiveness across quantitative and qualitative studies are equivocal, with a high risk of bias and small samples in the limited number of quantitative studies, demonstrating a need for high-quality RCTs.

SYSTEMATIC REVIEW PRE-REGISTRATION

PROSPERO [CRD42021244859].

Philadelphia Department of Health Doula Support Program: Early Successes and Challenges of a Program Serving Birthing People Affected by Substance Use Disorder

PURPOSE

Maternal substance use and deaths due to overdoses are increasing nationwide. Evidence suggests that the rate of resumed substance use, and fatal and non-fatal overdose is greatest in the first year after birth, particularly around six months postpartum, compared to other parts of the perinatal period. Doula care has been linked to improvements in perinatal health and outcomes.

DESCRIPTION

In response to the opioid epidemic, the Philadelphia Department of Public Health developed and implemented the Doula Support Program (DSP), with a focus on one year of postpartum care for birthing people with a substance use disorder (SUD). In this paper, we describe the program and its formation and report on the early challenges and successes of the program implementation, based on information we received from program founders and managers in a group interview.

ASSESSMENT

Early successes of the program include partnering with local community-based programs to recruit and retain doulas, supplementing traditional doula education with perinatal SUD-specific trainings, and maximizing client referrals by collaborating with local organizations and treatment centers that serve birthing people with SUD. Client retention, however, has proven to be challenging, especially during the COVID-19 pandemic.

CONCLUSION

The DSP continues to grow, and lessons learned will facilitate program improvements. The goal of this paper is to outline the development and launch of the DSP and to act as a model for other state and local health departments interested in providing doula care for birthing people with SUD.

Faculty caring behavior and effect on dental hygiene students' worry or anxiety

PURPOSE/OBJECTIVES

Studies in health professional students have shown the students' perception of instructor caring behaviors had a positive impact on student behaviors and their anxiety. Health professional students are under high emotional and academic demands during entry-level programs which can lead to higher anxiety. The purpose of this study was to measure the relationship between worry or anxiety and dental hygiene students' perceptions of faculty caring behaviors.

METHODS

Cross-sectional survey research was conducted with a convenience sample of dental hygiene students (n = 355) in the United States using a web-based survey. The validated instruments Nursing Students' Perceptions of Instructor Caring (NSPIC) and Penn State Worry Questionnaire (PSWQ) were used for data collection. The NSPIC contains five subscales including instilling confidence through caring (CTC), supportive learning climate, appreciation of life's meanings, control versus flexibility (F), and respectful sharing (RS). Data analysis included descriptive, correlation, and multiple linear regression.

RESULTS

The completion rate was 66% (n = 235). Findings showed the NSPIC subscale, CTC had a statistically significantly higher median score than other NSPIC sub-scales (p < 0001). The NSPIC subscale RS had the second-highest median score. The results of the PSWQ showed that 48% of participants were in the chronic worrier category. Regression analysis showed CTC was a significant predictor of worry (p < 0.001) and a one-unit increase in CTC resulted in a 0.21 decrease in the PSWQ score.

CONCLUSION

Our findings suggested instilling CTC behaviors was the most significant faculty caring behavior and was associated with lower levels of student worry. The results from this study may aid in identifying and developing effective caring behaviors for faculty to support students during stressful dental and allied dental curricula.

Age-period-cohort modelling of type 1 diabetes incidence rates among children included in the EURODIAB 25-year follow-up study

AIMS

Specific patterns in incidence may reveal environmental explanations for type 1 diabetes incidence. We aimed to study type 1 diabetes incidence in European childhood populations to assess whether an increase could be attributed to either period or cohort effects.

METHODS

Nineteen EURODIAB centres provided single year incidence data for ages 0-14 in the 25-year period 1989-2013. Case counts and person years were classified by age, period and cohort (APC) in 1-year classes. APC Poisson regression models of rates were fitted using restricted cubic splines for age, period and cohort per centre and sex. Joint models were fitted for all centres and sexes, to find a parsimonious model.

RESULTS

A total of 57,487 cases were included. In ten and seven of the 19 centres the APC models showed evidence of nonlinear cohort effects or period effects, respectively, in one or both sexes and indications of sex-specific age effects. Models showed a positive linear increase ranging from approximately 0.6 to 6.6%/year. Centres with low incidence rates showed the highest overall increase. A final joint model showed incidence peak at age 11.6 and 12.6 for girls and boys, respectively, and the rate-ratio was according to sex below 1 in ages 5-12.

CONCLUSION

There was reasonable evidence for similar age-specific type 1 diabetes incidence rates across the EURODIAB population and peaks at a younger age for girls than boys. Cohort effects showed nonlinearity but varied between centres and the model did not contribute convincingly to identification of environmental causes of the increase.

Orders of Protection

The feminist adage “the personal is political” is not ahistorical. It is being operationalized in a time when the relationship between the private and the public is undergoing historic transformation. Making privatized violence public under current conditions often involves channeling the most authoritarian tendencies of the state into relationships made increasingly desperate by the conditions of contemporary capitalism. The ethnographic focus of the essay is the work of a feminist organization operating in the context of Lavender Hill in Cape Town, a neighborhood created by apartheid forced removals and made more precarious by post-apartheid abandonment. The essay focuses on an explosion in the use of protection orders to compel police to intervene in the intimate relationships of households and neighbors, and offers an extended explanation of how and why feminism provides an exemplary case of reactionary politics for our times. The essay ends with a plea to draw on a different trajectory of feminism as a way of reconstituting a transformative political agenda, one that must take the historical transformations of racial capitalism seriously.

Evaluation of a General Practitioner with Special Interest model: lessons learned from staff experiences

BACKGROUND

The integration of general practitioners into specialist outpatient clinics is associated with improved access to care; however, little is understood about the organisation-level factors that affect successful implementation. We aimed to identify factors that were facilitators or barriers to the implementation of a General Practitioner with Special Interest (GPwSI) model of care across a range of specialties.

METHODS

Semi-structured, in-depth interviews were conducted with 25 stakeholders at 13 GPwSI clinics in operation within a Queensland public health service. A deductive content analysis was conducted using the Consolidated Framework for Implementation Research (CFIR).

RESULTS

Stakeholders generally supported the GPwSI model and saw advantages to patients and specialist medical practitioners in terms of waiting lists, workload, and improving clinician self-efficacy and knowledge. A number of factors were identified as being crucial to the success of the program, such as adequate support and planning for the implementation, appropriate funding and advocacy.

CONCLUSIONS

Our evaluation indicates that a GPwSI model can be a beneficial resource for improving care to patients and reducing wait lists, dependent upon adequate planning, training, and support.

Qualitative analysis of domestic violence detection and response in a tertiary hospital

INTRODUCTION Domestic and family violence is a public health problem of epidemic proportions and a significant issue facing the Australian community. It knows no boundaries, is indiscriminate to geographical location, social class, age, religious or cultural background. AIM This study aimed to analyse the processes currently used to identify and respond to domestic and family violence in a large tertiary hospital in Australia, and to classify the benefits and weaknesses of these existing systems. METHODS A qualitative method used semistructured, face-to-face and telephone interviews with key informants in 16 key areas across the hospital. Thematic analysis of the interviews was used to define the key issues and areas of interest identified by participants. RESULTS There was a dearth of existing guidelines or pathways of care for patients experiencing domestic violence. Several strengths and weaknesses were identified in relation to the protocols and systems used by the hospital, including limited training for staff and a lack of standardisation of processes, workplace instructions and clinical guidelines. With the exception of maternity services, no clinical service area used a guideline or work instruction. Most interviewees highlighted the need for the safety and protection of staff and victims as a priority. DISCUSSION Domestic and family violence is an enormous burden on the health system. However, many staff have little or no guidance on dealing with it or are unaware of existing protocols or guidelines for detection or response. Participants recommended further education and training for staff, consistent guidelines, specialist liaison and more educational and information resources for staff and patients. Further investigation and discussions with patients affected by violence is warranted to provide robust recommendations for policy change.

Plant science decadal vision 2020-2030: Reimagining the potential of plants for a healthy and sustainable future

Plants, and the biological systems around them, are key to the future health of the planet and its inhabitants. The Plant Science Decadal Vision 2020-2030 frames our ability to perform vital and far-reaching research in plant systems sciences, essential to how we value participants and apply emerging technologies. We outline a comprehensive vision for addressing some of our most pressing global problems through discovery, practical applications, and education. The Decadal Vision was developed by the participants at the Plant Summit 2019, a community event organized by the Plant Science Research Network. The Decadal Vision describes a holistic vision for the next decade of plant science that blends recommendations for research, people, and technology. Going beyond discoveries and applications, we, the plant science community, must implement bold, innovative changes to research cultures and training paradigms in this era of automation, virtualization, and the looming shadow of climate change. Our vision and hopes for the next decade are encapsulated in the phrase reimagining the potential of plants for a healthy and sustainable future. The Decadal Vision recognizes the vital intersection of human and scientific elements and demands an integrated implementation of strategies for research (Goals 1-4), people (Goals 5 and 6), and technology (Goals 7 and 8). This report is intended to help inspire and guide the research community, scientific societies, federal funding agencies, private philanthropies, corporations, educators, entrepreneurs, and early career researchers over the next 10 years. The research encompass experimental and computational approaches to understanding and predicting ecosystem behavior; novel production systems for food, feed, and fiber with greater crop diversity, efficiency, productivity, and resilience that improve ecosystem health; approaches to realize the potential for advances in nutrition, discovery and engineering of plant-based medicines, and "green infrastructure." Launching the Transparent Plant will use experimental and computational approaches to break down the phytobiome into a "parts store" that supports tinkering and supports query, prediction, and rapid-response problem solving. Equity, diversity, and inclusion are indispensable cornerstones of realizing our vision. We make recommendations around funding and systems that support customized professional development. Plant systems are frequently taken for granted therefore we make recommendations to improve plant awareness and community science programs to increase understanding of scientific research. We prioritize emerging technologies, focusing on non-invasive imaging, sensors, and plug-and-play portable lab technologies, coupled with enabling computational advances. Plant systems science will benefit from data management and future advances in automation, machine learning, natural language processing, and artificial intelligence-assisted data integration, pattern identification, and decision making. Implementation of this vision will transform plant systems science and ripple outwards through society and across the globe. Beyond deepening our biological understanding, we envision entirely new applications. We further anticipate a wave of diversification of plant systems practitioners while stimulating community engagement, underpinning increasing entrepreneurship. This surge of engagement and knowledge will help satisfy and stoke people's natural curiosity about the future, and their desire to prepare for it, as they seek fuller information about food, health, climate and ecological systems.

Improving women's experience during speculum examinations at routine gynaecological visits: randomised clinical trial

OBJECTIVES

To determine if a standardised method of leg positioning without stirrups reduces the physical discomfort and sense of vulnerability and increases the sense of control among women undergoing speculum examination as part of a routine gynaecological examination.

DESIGN

Randomised clinical trial.

SETTING

Family medicine outpatient clinic.

PATIENTS

197 adult women undergoing routine gynaecological examination and cervical smear.

INTERVENTION

Examination with or without stirrups.

MAIN OUTCOME MEASURES

Women's perceived levels of physical discomfort, sense of vulnerability, and sense of control during the examination, measured on 100 mm visual analogue scales.

RESULTS

Women undergoing examination without stirrups had a reduction in mean sense of vulnerability from 23.6 to 13.1 (95% confidence interval of the difference - 16.6 to - 4.4). Mean physical discomfort was reduced from 30.4 to 17.2 (- 19.7 to - 6.8). There was no significant reduction in sense of loss of control.

CONCLUSION

Women should be able to have gynaecological examinations without using stirrups to reduce the stress associated with speculum examinations.

TRIAL REGISTRATION

US Army Central Investigation Regulatory Office. Trial No DDEAMC 05-11.

A prognostic index for operable, node-negative breast cancer

Clinical data and samples from patients diagnosed, more than 10 years previously, with operable node-negative breast cancer (participants in the Scottish Adjuvant Tamoxifen trial), were revisited. Cases with two distinct categories of outcome were selected; more than 10 years disease-free survival ('good outcome') or distant relapse within 6 years of diagnosis ('poor outcome'). An initial set of cases was analysed for a range of putative prognostic markers and a prognostic index, distinguishing the two outcome categories, was calculated. This index was then validated by testing its predictive power on a second, independent set of cases. A combination of histological grade plus immunochemical staining for BCL-2, p27 and Cyclin D1, generated a useful prognostic index for tamoxifen-treated patients but not for those treated by surgery alone. The value of the index was confirmed in a second set of tamoxifen-treated, early stage breast cancers. Overall, it correctly predicted good and poor outcome in 79 and 74% of cases, respectively (odds ratio 11.0). Other markers assessed added little to prediction of outcome. In the case of molecular assays, sensitivity and reliability were compromised by the age of the tissue specimens and the variability of fixation protocols. In selecting patients for adjuvant systemic chemotherapy, the proposed index improves considerably on current international guidelines and matches the performance reported for 'gene-expression signature' analysis.

Heterogeneous vascular endothelial growth factor (VEGF) isoform mRNA and receptor mRNA expression in human glomeruli, and the identification of VEGF148 mRNA, a novel truncated splice variant

Vascular endothelial growth factor (VEGF) mediates increased vascular permeability and endothelial mitogenesis, and may orchestrate normal glomerular permselectivity and proteinuria. Distinct isoforms result from differential gene splicing. VEGF binds to two cell surface tyrosine-kinase receptors, KDR (kinase domain region) and Flt-1 (fms-like tyrosine kinase-1). The latter also exists in a soluble form (sFlt), which is inhibitory. We have studied patterns of VEGF-isoform and VEGF-receptor expression in isolated single normal human glomeruli. mRNA from 190 glomeruli (from 20 individuals) was harvested on to magnetic beads, and nested reverse transcription-PCR was performed using primers for the VEGF isoforms and VEGF receptors. Simultaneous nested reverse transcription-PCR for CD45 was conducted in order to exclude leucocyte contamination. Unexpected products were isolated, cloned and sequenced. Multiple patterns of glomerular VEGF mRNA isoform expression were identified. Most frequently (58%), all three common forms were expressed. VEGF(189) (i.e. 189-amino-acid form of VEGF) was expressed in 63%, VEGF(165) in 85% and VEGF(121) in 84% of glomeruli. Two unexpected PCR products were also identified: 18% of glomeruli expressed VEGF(145), and 27% of glomeruli expressed a new truncated VEGF splice variant, VEGF(148), lacking exon 6, the terminal part of exon 7 and exon 8. Multiple patterns of VEGF-receptor expression were also identified, the most common being expression of all three isoforms (28%). Overall, KDR was seen in 59% of glomeruli, Flt-1 in 45% and sFlt in 57%. Thus the expression of VEGF within normal glomeruli is complex and variable, with inter- and intra-individual variation. Furthermore, sFlt appears to be the co-dominant form of VEGF receptor expressed within glomeruli, suggesting that, in healthy individuals, a degree of VEGF autoregulation is the norm. The physiological importance of VEGF(148) remains to be confirmed.

Risk factors for suicide independent of DSM-III-R Axis I disorder. Case-control psychological autopsy study in Northern Ireland

BACKGROUND

The vast majority of suicides suffer from at least one mental disorder at the time of death.

AIMS

To identify risk factors for suicide, particularly those independent of current DSM-III-R Axis I disorder(s).

METHOD

A case-control psychological autopsy study comparing suicides with matched community controls.

RESULTS

Independent risk factors for suicide included: Axis II (personality) disorder (particularly antisocial, avoidant and dependent); at least one of 12 life events (from the List of Threatening Experiences) during the previous 52 or 4 weeks (in particular, a 'serious problem with close friend, neighbour or relative'); current unemployment; previous history of deliberate self-harm; and contact with a GP within 26 weeks. Relative to individuals with no current mental disorder, the estimated risk of suicide in those with Axis I-Axis II comorbidity (OR 346.0) was significantly greater than that in those with Axis I disorder(s) only (OR 52.4).

CONCLUSIONS

Suicide risk assessment may be enhanced by enquiry about the aforementioned independent risk factors, and attention to Axis I-Axis II comorbidity.

Strategies of myocardial protection for operation in chronic model of cyanotic heart disease

BACKGROUND

Cyanotic congenital hearts have an increased susceptibility to ischemia and subsequent reperfusion. The role of platelet-activating factor antagonism and mechanical neutrophil depletion with leukocyte-depleting filters for control of ischemia-reperfusion injury was assessed in corrective surgical procedures for cyanotic heart disease.

METHODS

A swine model of cyanotic heart disease was evaluated with three study groups: a control group; a group given a platelet-activating factor antagonist (PAFA group); and a group with leukocyte-depleting filtration (LDF group). The cyanotic model was created with a left atrial appendage-pulmonary artery fistula with peripheral banding through a left anterior thoracotomy in weanling swine. The experimental procedure was performed 5 to 7 weeks later when body weight was greater than 20 kg and oxygen saturation was 85% or less. The corrective procedure was performed through a median sternotomy on cardiopulmonary bypass with repair of the shunt. Myocardial protection was accomplished with hypothermic blood-crystalloid (4:1) cardioplegia; the period of ischemic arrest was 90 minutes. In the PAFA group, the platelet-activating factor antagonist CV-6209 was delivered intravenously 15 to 20 minutes before aortic cross-clamping. In the LDF group, Pall leukocyte-depleting filters were used in the CPB arterial line. Hemodynamic data were taken before operation and 10 and 30 minutes after CPB with impedance ventriculography.

RESULTS

There were four deaths in the control group within 30 minutes after CPB; all animals in the treated groups survived longer than 60 minutes (p < 0.05). The ventricular assessment of end-systolic elastance revealed superior performance in the LDF group 30 minutes after CPB compared with the control group (p < 0.05) (controls, 4.0+/-9; PAFA group, 6.5+/-3.7; and LDF group, 12.0+/-4.6).

CONCLUSIONS

Both leukocyte-depleting filters and platelet-activating factor antagonism provided myocardial protection, and the filters afforded superior postoperative myocardial contractility.

Gold and D-penicillamine induce vasculitis and up-regulate mRNA for IL-4 in the Brown Norway rat: support for a role for Th2 cell activity

D-penicillamine (DP) and gold salts which are used as immune-modulating agents in the treatment of rheumatoid arthritis are known to be capable of causing autoimmune manifestations. Most autoimmune diseases in man are dominated by Th1-type responses, and one might presume that effective immunotherapy counteracts Th activity, perhaps by causing a shift to a Th2 response. The mechanism of action of gold and DP is not clear, but some clues may be obtained from their effects in animal models. DP, gold salts and mercuric chloride (HgCl2) are known to induce Th2-dominated autoimmune syndromes in genetically susceptible rodent strains, and we have demonstrated recently that HgCl2 up-regulates messenger RNA (mRNA) for IL-4 in the Brown Norway (BN) rat. In the BN rat HgCl2 treatment is also associated with the development of vasculitis, and anti-myeloperoxidase (MPO) antibodies are found in the serum. The present study examined and confirmed the hypothesis that, since gold and DP induce an autoimmune syndrome similar to HgCl2 in the BN rat, they may also induce vasculitis and an up-regulation in mRNA for IL-4. Tissue injury was assessed macroscopically and histologically on day 5 and day 15 after the start of injections with gold, DP or HgCl2, serum titres of IgE and presence of anti-MPO antibodies were determined using ELISA, and a semi-quantitative assay using reverse transcription-polymerase chain reaction was used to assay the level of mRNA for IL-4 in spleen and caecum. The relative degree of tissue injury reflected the potency of induction of IgE by the three agents (HgCl2 being most potent and DP least potent). The lesions were identical histologically, supporting the premise that the vasculitis is a manifestation of the autoimmune syndrome rather than non-specific HgCl2 toxicity. Both gold and DP induced less up-regulation of mRNA for IL-4 than HgCl2. HgCl2 (but not gold or DP) induced anti-MPO antibodies. It would be interesting to examine patients treated with gold and DP to see if there is evidence of a Th2-type response in those developing autoimmune complications, and whether or not the bias to a Th2 environment contributes to efficacy of treatment of the underlying disease.

Mental disorders and suicide in Northern Ireland

BACKGROUND

The aim of this part of the Northern Ireland Suicide Study was to investigate the prevalence of DSM-III-R axis I (clinical syndrome) and axis II (personality) disorders among suicides (14 years and older) in Northern Ireland during a one-year period.

METHOD

A psychological autopsy study based on a variety of documentary sources and interviews with bereaved informants and health care professionals.

RESULTS

Ninety per cent of suicides (106/118) had a current axis I and/or an axis II mental disorder. At least one current axis I disorder was diagnosed in 86% of suicides (102/118), and at least one axis II disorder was diagnosed in 44% (52/118). Suicides under 30 years (92% male) were less likely to have a current axis I disorder (68%; 26/38) than those 30 years and older (95%; 76/80). Psychiatric comorbidity was present in 55% of suicides (65/118). The time between the last contact with a health care professional and death was greater among suicides under 30 years and male suicides.

CONCLUSIONS

Notwithstanding the aetiological complexity of suicide, the prevention, recognition and treatment of mental disorder will continue to play key roles in suicide prevention.

Serum IgE concentration and other immune manifestations of treatment with gold salts are linked to the MHC and IL4 regions in the rat

A subset of patients with rheumatoid arthritis occasionally develops skin reactions and glomerulonephritis and exhibits an increase in serum IgE concentration when treated with gold salts. Brown-Norway (BN) rats injected with aurothiopropanolsulfonate (ATPS) also manifest an autoimmune glomerulonephritis and increased serum IgE concentration, whereas Lewis (LEW) rats are resistant to complications. Here, we show linkage between responses to ATPS in a (BN x LEW) F2 cohort and the major histocompatibility complex (RT1) on rat chromosome 20 and between markers in the region of IL4 and other candidate genes on rat chromosome 10. Recently, human serum IgE concentration has been reported to be linked to the IL-4 region. Taken together, these findings raise the possibility that homologous genes could be implicated in ATPS manifestations in the rat and in the regulation of IgE levels in the human.

Compounds that induce autoimmunity in the brown Norway rat sensitize mast cells for mediator release and interleukin-4 expression

Brown Norway (BN) rats given mercuric chloride (HgCl2), gold (Au) salts or D-penicillamine develop a T helper 2 (Th2) cell-mediated autoimmune syndrome. The recent observation of tissue injury within 24 h of HgCl2 treatment suggested the involvement of a non-T cell. We therefore examined the effect of these compounds on rat mast cells in vitro. Incubation of BN rat peritoneal mast cells with HgCl2 enhanced the release of serotonin in response to IgE cross-linking agents. Mast cells from Lewis rats, a strain not susceptible to the autoimmune syndrome in vivo, were affected to a lesser extent. The effect was observed with purified BN mast cells, suggesting a direct action. Similar effects were seen with D-penicillamine in the presence of copper ions, a combination that produces hydrogen peroxide, and Au. HgCl2 caused significant induction of interleukin (IL)-4 mRNA in mast cells from BN, but not Lewis rats. The data demonstrate a novel enhancing effect of a number of compounds on mast cell mediator release, and an inducing effect of HgCl2 on mast cell IL-4, expression. These findings are consistent with our hypotheses that mast cells may contribute to early tissue injury, and also, via production of IL-4, may initiate and/or augment, the Th2 response in the BN rat model of chemical-induced autoimmunity.

Reduced clearance of exogenous dopamine in rat nucleus accumbens, but not in dorsal striatum, following cocaine challenge in rats withdrawn from repeated cocaine administration

We investigated whether changes in the dopamine transporter in the nucleus accumbens or striatum are involved in cocaine-induced behavioral sensitization by using in vivo electrochemistry to monitor the clearance of locally applied dopamine in anesthetized rats. Rats were injected with cocaine-HCl (10 mg/kg i.p.) or saline daily for 7 consecutive days and then withdrawn for 7 days. Pressure ejection of a finite amount of dopamine at 5-min intervals from a micropipette adjacent to the electrochemical recording electrode produced transient and reproducible dopamine signals. After a challenge injection of cocaine (10 mg/kg i.p.), the signals in the nucleus accumbens of cocaine-treated animals became prolonged and the clearance rate of the dopamine decreased, indicating significant inhibition of the dopamine transporter. In contrast, simultaneous measurements in the dorsal striatum indicated a transient increase in both the amplitude of the signals and the clearance rate of the dopamine. The signals in both brain regions in the saline-treated animals given the cocaine challenge were similar to those in untreated animals given an acute injection of cocaine (10 mg/kg i.p.) or saline. Behaviorally, not all of the cocaine-treated animals were sensitized; however, both sensitized and nonsensitized animals displayed similar changes in dopamine clearance rate. Quantitative autoradiography with [3H]mazindol revealed that the affinity of the dopamine transporter for cocaine and the density of binding sites were similar in cocaine- and saline-treated rats. The decrease in dopamine clearance rate observed in the nucleus accumbens of the cocaine-treated rats after a challenge injection of cocaine is consistent with increased dopaminergic transmission, but does not appear to be sufficient in itself for producing behavioral sensitization.

Fragile X mental retardation and the iduronate sulphatase locus: testing Laird's model of fra(X) inheritance

Fragile X [fra(X)] mental retardation syndrome is the most frequent familial cause of mental handicap. The clinical phenotype is associated with a rare fragile site at Xq27.3. The mutation underlying the disorder, an insertion into the FMR-1 gene, has been characterized, but the pathogenesis of the condition is obscure and the pattern of inheritance is still not fully understood. One model of fra(X) pathogenesis was proposed by Laird in 1987, suggesting that the fra(X) mutation acts as a cis-acting, local block to the pre-oogenesis reactivation of the inactivated X chromosome. To test this model, we examined the activity of the F8, F9 and iduronate sulphatase (IDS) loci. The level of IDS in the serum of fra(X) males was found to be very significantly reduced in the fra(X) group when compared to that of control males: this lends support to Laird's model of fra(X) pathogenesis. However, we detected no methylation differences between fra(X) and control samples at the IDS locus, although such changes are known in fra(X) males at sites closer to the fragile site. Thus the mechanism of the reduction in IDS activity has not been identified.

Preservation techniques for heart transplantation: comparison of hypothermic storage and hypothermic perfusion

Preservation of the donor heart is an important and controversial subject in heart transplantation. This study compares simple hypothermic storage and hypothermic perfusion in a swine model of heart transplantation (n = 14). The donor hearts of group A (n = 7) were placed in simple hypothermic storage for 5 hours. The donor hearts of group B (n = 7) were placed onto a perfusion apparatus for 5 hours, with pressure maintained at 28 cm of H2O and a myocardial temperature of 8 to 10 degrees C. In both groups the hearts were initially protected with isosmolar potassium cardioplegic solution. The perfusate in group B contained moderate sodium, mannitol, glucose, insulin, and oxygen. The ischemic interval within both groups was 6 hours including orthotopic transplantation. Investigation was conducted at three time periods: prepreservation, postpreservation, and immediately after loading. For both groups there was nonsignificant depression of myocardial function (cardiac index, stroke index, stroke work index, ejection fraction, and wall stress) at the postpreservation period. After volume loading, for the hypothermic perfusion group there was significant improvement of myocardial function (cardiac index, p less than 0.01; stroke index, p less than 0.01) with no significant change in heart rate, systemic vascular resistance, and systolic blood pressure. There was also significant improvement in myocardial performance (p less than 0.05) for the hypothermic perfusion group after volume loading. Ultrastructural changes were minimal for both groups, and there were no major heart transplantation after 6 hours of ischemia; however, hearts retain their contractile capacity better after hypothermic perfusion than after simple hypothermic storage.(ABSTRACT TRUNCATED AT 250 WORDS)

Improving the validity of the GHO30 by rescoring for chronicity: a failure to replicate

To replicate the finding by Goodchild and Duncan-Jones (1985), that rescoring the GHQ30 in order to take account of chronicity would improve its validity, a random sample of 244 people completed the GHQ. Of these 102 also took part in a second interview in which they were administered the PSE. There was no evidence that the new scoring scheme improved correlations between the GHQ and other measures of morbidity nor did this improve its sensitivity or specificity when validated agaist the PSE.

Comparison of standard and chlorhexidine-derivative topical antibacterial agents on the infected burned rat wound

The effect of daily treatment with three current topical antibacterial agents and four experimental formulations of chlorhexidine was evaluated after 1 week in rats with full thickness burns. The burn was seeded with 1 x 10(8) colony forming units (CFU) of a strain of P. aeruginosa isolated from the infected wound of a burn patient. Mafenide acetate resulted in the lowest incidence of muscle invasion and yielded the lowest mean eschar and muscle concentrations. Mafenide acetate, gentamicin, and chlorhexidine diphosphanilate (0.5 per cent) had lower mean eschar and muscle concentrations than silver sulphadiazine 1 per cent alone. Addition of chlorhexidine digluconate (0.5 per cent or 1.0 per cent) to silver sulphadiazine reduced mean eschar concentrations but not muscle concentrations compared to silver sulphadiazine alone. All treatments effectively suppressed systemic invasion of lung and blood and prevented death compared with controls. Mafenide acetate, gentamicin sulphate and chlorhexidine disphosphanilate 0.5 per cent were most effective against this patient strain of P. aeruginosa.

Chromosomal locations of three Bacillus subtilis din genes

Previously isolated DNA damage-inducible (din) genes of Bacillus subtilis have been mapped on the bacterial chromosome by bacteriophage PBS1-mediated transduction. The din genes have been localized to three positions on the B. subtilis map. dinA cotransduction with the hisA locus was 80%, while dinC cotransduction with this marker was about 56%. dinB is unlinked to hisA, but its cotransduction with the dal-1 and purB loci was 84 and 22%, respectively.

The effect of refreshments on attendance at recreation activities for nursing home residents

Activity directors must recognize variables which increase patient involvement by nursing home residents. Refreshments are one variable which can be used to increase the attendance of the aged at recreation activities. This study was conducted to determine if refreshments had an effect on attendance at recreation activities for residents requiring various care levels and in different activities in a nursing home. The mean attendance at activities when refreshments were provided was compared to the mean attendance at activities when refreshments were not provided for three resident care levels. A paired-comparison t-test indicated refreshments were effective in increasing attendance at activities for residents at all competence levels. These results will be helpful to activity directors who may desire to increase attendance.

Hemodynamic effects of intravenous amiodarone in patients with depressed left ventricular function and recurrent ventricular tachycardia

The systemic hemodynamic effects of intravenously administered amiodarone were evaluated in patients with depressed left ventricular function and recurrent sustained ventricular tachycardia. Heart rate decreased linearly up to 1 hour after amiodarone infusion (5 mg/kg). Cardiac index varied in a cubic fashion, diminishing at 10 minutes and returning to baseline by 60 minutes (p less than 0.05). Stroke work index also showed a similar decrease at 10 minutes, which was transient (p less than 0.005). These changes occurred without any significant change in systemic vascular resistance and with slight or no increase in pulmonary capillary wedge pressure, indicating a negative inotropic effect of amiodarone. The depression of left ventricular function in these patients, however, was mild and transient, and intravenously administered amiodarone was tolerated by the vast majority of patients. In two patients with overt heart failure and severely depressed left ventricular ejection fraction and marked hemodynamic abnormalities, profound hypotension occurred during amiodarone therapy; in such patients, therefore, hemodynamic monitoring is preferable. Limited data are available on the hemodynamic effects of orally administered amiodarone, but the determination of left ventricular ejection fraction by radionuclide ventriculography before and during long-term amiodarone administration has shown no reduction of function even in patients with severely reduced myocardial performance.