The outcomes of health-promoting communities: being active eating well initiative-a community-based obesity prevention intervention in Victoria, Australia.

OBJECTIVE: The aim of this study is to evaluate the impact of the Health-Promoting Communities: Being Active Eating Well (HPC:BAEW, 2007-2010) initiative, which comprised community-based multi-component interventions adapted to community context in five separate communities. The intervention aimed to promote healthy eating, physical activity and stronger, healthier communities. METHODS: A mixed method and multilevel quasi-experimental evaluation of the HPC:BAEW initiative captured process, impact and outcome data. The evaluation involved both cross-sectional (children and adolescents) and longitudinal designs (adults) with data collected pre- and post-intervention in intervention (n=2408 children and adolescents from 18 schools, n=501 adults from 22 workplaces) and comparison groups (n=3163 children and adolescents from 33 schools, n=318 adults from seven workplaces). Anthropometry, obesity-related behavioural and environmental data, information regarding community context and implementation factors were collected. The primary outcomes were differences in anthropometry (weight, waist, body mass index (BMI) and standardised BMI (BMI z-score)) over time compared with comparison communities. Baseline data was collected 2008/2009 and post-intervention collected in 2010 with an average intervention time frame of approximately 12 months. RESULTS: The strategies most commonly implemented were related to social marketing, stakeholder engagement, network and partnership development, community-directed needs assessment and capacity building. Analysis of post-intervention data showed gains in community capacity, but few impacts on environments, policy or individual knowledge, skills, beliefs and perceptions. Relative to the comparison group, one community achieved a lower prevalence of overweight/obesity, lower weight, waist circumference and BMI (P<0.005). One community achieved a higher level of healthy eating policy implementation in schools; two communities achieved improved healthy eating-related behaviours (P<0.03); one community achieved lower sedentary behaviours; and one community achieved higher levels of physical activity in schools (P<0.05). All effect sizes were in the small-to-moderate range. CONCLUSIONS: This was a complex and ambitious initiative, which attempted to expand a previously successful community-based intervention in Victoria into five new contexts and communities. Overall, project success was quite inconsistent, and some significant differences were in the unanticipated direction. However, there are many important learnings that should inform future health-promotion activities. The heterogeneity of outcomes of HPC:BAEW communities reflects the reality of life whereby effectiveness of intervention strategies is dependent on individual and community factors. Future health promotion should consider a systems approach whereby existing systems are modified rather than relying heavily on the addition of new activities, with longer time frames for implementation.

Child oral health in migrant families: A cross-sectional study of caries in 1-4 year old children from migrant backgrounds residing in Melbourne, Australia.

UNLABELLED: Early Childhood Caries (ECC) is the most common, preventable disease of childhood. It can affect children's health and wellbeing and children from migrant families may be at greater risk of developing ECC. OBJECTIVE: To describe ECC in children from migrant families, and explore possible influences. BASIC RESEARCH DESIGN: Cross-sectional analysis of caries data collected as baseline data for an oral health promotion study. PARTICIPANTS: The analysis sample included 630 1-4 year-old children clustered within 481 Iraqi, Lebanese and Pakistani families in Melbourne, Australia. METHOD: Child participants received a community-based visual dental examination. Parents completed a self-administered questionnaire on demographics, ethnicity, and oral health knowledge, behaviour and attitudes. MAIN OUTCOME MEASURE: Child caries experience. Bivariate associations between oral health behaviours and ethnicity were tested for significance using chi-square. Multivariate logistic regression analyses were performed to identify associations with ECC, adjusting for demographic variables and accounting for clustering by family. RESULTS: Overall, 34% of children in the sample experienced caries (both non-cavitated and cavitated). For all caries lesions, parent' length of residence in Australia, consumption of sweet drinks and parental education remained as independent predictors of child caries experience. Adding sugar to drinks was an additional risk factor for cavitation. Ethnicity was associated with some individual oral health behaviours suggesting cultural influences on health, however the relationship was not independent of other predictors. CONCLUSION: Culturally competent oral health promotion interventions should aim to support migrant families with young children, and focus on reducing sweet drink consumption.

Choosing foods for infants: a qualitative study of the factors that influence mothers.

BACKGROUND: Examining the experiences of parents making food choices for infants is important because ultimately this influences what infants eat. Infancy is a critical period when food preferences and eating behaviour begin to develop, shaping dietary patterns, growth and health outcomes. There is limited evidence regarding what or why foods are chosen for infants. OBJECTIVE: To describe the experiences of mothers making food choices for their infant children. METHODS: Semi-structured interviews with 32 Australian mothers of infants aged four to 15 months from a range of socioeconomic backgrounds. An inductive thematic analysis through a process of constant comparison was conducted on transcribed interviews. RESULTS: Mothers described many ideas and circumstances which influenced food choices they made for infants. Themes were developed which encapsulate how the wider environment and individual circumstances combine to result in the food choices made for infants. Beliefs, values, norms and knowledge were a central influence on choices. Cost, quality and availabilities of various foods were also key factors. Related to this, and combined with inherent factors such as perishability and infant acceptability, fresh fruits and vegetables were often singled out as an easy or difficult choice. Influences of time, parents' capacities, social connections and different information sources were clearly apparent. Finally infants' own preferences and how parents helped infants with learning to eat were also key influences on food choices. CONCLUSIONS: Choosing foods for infants is a complex social practice. An ecological framework depicting the multiple influences on what people eat and sociological theory on food choice regarding the role of 'social structure' and 'human agency' are both applicable to the process of choosing foods for infants. Equity issues may be key regarding the degree to which mothers can choose particular foods for infants (e.g. choosing foods which promote health).

Mild phenotype in a male with pyruvate dehydrogenase complex deficiency associated with novel hemizygous in-frame duplication of the E1α subunit gene (PDHA1).

Pyruvate dehydrogenase complex (PDHC) deficiency is an inborn error of metabolism that occurs most commonly due to mutations in the X-linked E1α subunit gene (PDHA1). We report a novel duplication of PDHA1 associated with a mild phenotype in a 15-year-old boy who was diagnosed with PDHC deficiency at 4 years of age following a history of seizures and lactic acidosis. The novel c.1087_1119 mutation in exon 11 resulted in an in-frame duplication of 11 amino acids. Measurements of PDHC activity in cultured skin fibroblasts were low, corresponding to 18.6 and 11.6% of the mean with respect to prior controls, whereas the E1 PDH component was absent. He has borderline intellectual functioning and maintains normal lactate levels on a ketogenic diet in between relapses due to illness. Review of the literature reveals wide variation of clinical phenotype in patients with mutations of the E1α subunit gene (PDHA1). There appears to be a higher incidence of normal or borderline intellectual ability in individuals who have insertions or deletions that are in-frame versus those that are out-of-frame. Furthermore, there is no correlation between mean residual PDH activity and phenotype in these patients.

Methodology for the evaluation of the Stephanie Alexander Kitchen Garden program.

ISSUES ADDRESSED: Community and school cooking and gardening programs have recently increased internationally. However, despite promising indications, there is limited evidence of their effectiveness. This paper presents the evaluation framework and methods negotiated and developed to meet the information needs of all stakeholders for the Stephanie Alexander Kitchen Garden (SAKG) program, a combined cooking and gardening program implemented in selectively funded primary schools across Australia. METHODS: The evaluation used multiple aligned theoretical frameworks and models, including a public health ecological approach, principles of effective health promotion and models of experiential learning. The evaluation is a non-randomised comparison of six schools receiving the program (intervention) and six comparison schools (all government-funded primary schools) in urban and rural areas of Victoria, Australia. A mixed-methods approach was used, relying on qualitative measures to understand changes in school cultures and the experiential impacts on children, families, teachers, parents and volunteers, and quantitative measures at baseline and 1 year follow up to provide supporting information regarding patterns of change. RESULTS: The evaluation study design addressed the limitations of many existing evaluation studies of cooking or garden programs. The multistrand approach to the mixed methodology maintained the rigour of the respective methods and provided an opportunity to explore complexity in the findings. Limited sensitivity of some of the quantitative measures was identified, as well as the potential for bias in the coding of the open-ended questions. CONCLUSION: The SAKG evaluation methodology will address the need for appropriate evaluation approaches for school-based kitchen garden programs. It demonstrates the feasibility of a meaningful, comprehensive evaluation of school-based programs and also demonstrates the central role qualitative methods can have in a mixed-method evaluation. So what? This paper contributes to debate about appropriate evaluation approaches to meet the information needs of all stakeholders and will support the sharing of measures and potential comparisons between program outcomes for comparable population groups and settings.

The effect of the Australian bushfires and the COVID-19 pandemic on health behaviours in people with multiple sclerosis.

BACKGROUND: Crises and disasters disproportionally impact people with chronic health conditions such as multiple sclerosis (MS). OBJECTIVE: To assess the impact of the COVID-19 pandemic and the Australian Black Summer Bushfires on health behaviours in people with MS. METHODS: People with MS, carers, healthcare and advocacy professionals were recruited online between May-July 2020 for an online survey and telephone interviews. RESULTS: Survey items relating to health behaviours were completed by 113 people with MS, and 18 people with MS, 4 MS advocates, 5 healthcare professionals, and 2 carers were interviewed. The bushfires affected 34.5% and the pandemic affected 74.3% of survey participants with MS. The pandemic and bushfires caused a decrease in physical activity in 53.8% and 55.3% of participants respectively, as well as increases in unhealthy eating (43.6% and 24.3% respectively) and alcohol consumption (35.4% and 10.5% respectively), and a decrease in typical sleeping patterns (40.5% and 39.5% respectively). Conversely, 27.5% of participants reported an increase in physical activity during the pandemic. Interview data detailed the circumstances and motivations for changes in health behaviours, as well as consequences, including reduced mobility, fitness, mood disturbances, and weight gain. CONCLUSION: There is a need to increase support and health promotion for people with MS to maintain or initiate positive health behaviours, especially in times of adversity.

Assessing the feasibility of distributing child poison safety messages through three existing parent information pathways.

The objective of this exploratory study was to assess the feasibility of increasing parents' poison safety awareness and behaviours using existing pathways. The aim was to compare the release of true stories of child unintentional poisoning via three modes: (a) parent "networker"; (b) maternal and child health nurse; (c) the media. The stories spread by the parent networker were readily recalled by the parents, with examples of changed behaviour and spreading of the stories. Parents who were part of the maternal and child health nurse strategy were not able to recall the stories without prompts. The media strategy could not be implemented because of difficulties finding parents ready to publicise their story. Given that it is an exploratory study, it is not possible to draw conclusions about the effectiveness of each of the intervention strategies. However, it appears that a low-resource intervention using stories shared via parent networkers may have exciting potential as a health promotion tool. A stronger study design to examine its effectiveness is proposed.

Temporal development of the oral microbiome and prediction of early childhood caries.

Human microbiomes are predicted to assemble in a reproducible and ordered manner yet there is limited knowledge on the development of the complex bacterial communities that constitute the oral microbiome. The oral microbiome plays major roles in many oral diseases including early childhood caries (ECC), which afflicts up to 70% of children in some countries. Saliva contains oral bacteria that are indicative of the whole oral microbiome and may have the ability to reflect the dysbiosis in supragingival plaque communities that initiates the clinical manifestations of ECC. The aim of this study was to determine the assembly of the oral microbiome during the first four years of life and compare it with the clinical development of ECC. The oral microbiomes of 134 children enrolled in a birth cohort study were determined at six ages between two months and four years-of-age and their mother's oral microbiome was determined at a single time point. We identified and quantified 356 operational taxonomic units (OTUs) of bacteria in saliva by sequencing the V4 region of the bacterial 16S RNA genes. Bacterial alpha diversity increased from a mean of 31 OTUs in the saliva of infants at 1.9 months-of-age to 84 OTUs at 39 months-of-age. The oral microbiome showed a distinct shift in composition as the children matured. The microbiome data were compared with the clinical development of ECC in the cohort at 39, 48, and 60 months-of-age as determined by ICDAS-II assessment. Streptococcus mutans was the most discriminatory oral bacterial species between health and current disease, with an increased abundance in disease. Overall our study demonstrates an ordered temporal development of the oral microbiome, describes a limited core oral microbiome and indicates that saliva testing of infants may help predict ECC risk.

Ethical Use and Impact of Participatory Approaches to Research in Post-Disaster Environments: An Australian Bushfire Case Study.

This paper presents a case study of Beyond Bushfires, a large, multisite, mixed method study of the psychosocial impacts of major bushfires in Victoria, Australia. A participatory approach was employed throughout the study which was led by a team of academic investigators in partnership with service providers and government representatives and used on-site visits and multiple methods of communication with communities across the state to inform decision-making throughout the study. The ethics and impacts of conducting and adapting the approach within a post-disaster context will be discussed in reference to theories and models of participatory health research. The challenges of balancing local interests with state-wide implications will also be explored in the description of the methods of engagement and the study processes and outcomes. Beyond Bushfires demonstrates the feasibility of incorporating participatory methods in large, post-disaster research studies and achieving rigorous findings and multilevel impacts, while recognising the potential for some of the empowering aspects of the participatory experience to be reduced by the scaled-up approach.

Short-term outcomes of inborn v. outborn very-low-birth-weight neonates (<1 500 g) in the neonatal nursery at Groote Schuur Hospital, Cape Town, South Africa.

BACKGROUND: The Groote Schuur Hospital (GSH) neonatal nursery provides level 3 care for the Metro West Health District in the Western Cape Province of South Africa. Worldwide, very-low-birth-weight (VLBW) neonates delivered in level 3 neonatal units have better outcomes than those transported from other facilities. OBJECTIVES: To identify the characteristics and outcomes of VLBW neonates at GSH, with emphasis on differences between inborns and outborns. METHODS: This was a retrospective cohort study. VLBW neonates admitted to the GSH neonatal nursery between 1 January 2012 and 31 December 2013 were enrolled on the Vermont Oxford Network database and reviewed. RESULTS: Of 1 032 VLBW neonates enrolled, 906 (87.8%) were delivered at GSH and 126 (12.2%) were outborn. Access to antenatal care, antenatal steroids and inborn status were statistically significant predictors of mortality and survival without morbidity. The mothers of inborn patients were more likely than those of outborn patients to have received antenatal care (89.1% v. 57.9%; p<0.0001) and antenatal steroids (64.2% v. 15.2%; p<0.0001). Inborns required less ventilatory support (16.2% v. 57.9%; p<0.0001) and surfactant administration than outborns (25.3% v. 65.1%; p<0.0001), and developed less late infection (8.8% v. 23.4%; p<0.0001), severe intraventricular haemorrhage (3.7% v. 13.9%; p<0.0001) and chronic lung disease (5.3% v. 13.4%; p=0.003). The incidence of necrotising enterocolitis was similar in the two groups (5.9% v. 8.7%; p=0.227). The mortality rate was 18.4% for inborns and 33.3% for outborns (p<0.0001). Mortality declined as birth weight increased. Of the survivors, 85.0% of inborns and 70.2% of outborns did not develop serious morbidity (p=0.003). CONCLUSIONS: VLBW neonates delivered at GSH had better outcomes than their outborn counterparts. Perinatal regionalisation is beneficial to our patients, with antenatal care, timeous transfer in utero and antenatal steroids contributing to excellent outcomes.

CD18 integrin-dependent endothelial injury: effects of opsonized zymosan and phorbol ester activation.

We examined the hypothesis that neutrophil (PMN)-mediated injury of the vascular endothelium is dependent on adhesion of PMNs to endothelial cells via the leukocyte adhesion glycoprotein CD11/CD18. We compared the PMN activation responses [i.e. adhesion to cultured endothelial cells, superoxide (O2-) production, degranulation, and cytosolic [Ca2+] ([Ca2+]i)] and endothelial injury elicited by opsonized zymosan (OZ, which is phagocytosed by PMNs) or phorbol 12-myristate 13-acetate (PMA, a protein kinase C activator). The basal adherence of nonstimulated PMNs to bovine pulmonary artery endothelial cells (BPAEC) was 9.0 +/- 1.1 PMN/field. PMA and OZ increased PMN adherence to BPAEC (to 31.1 +/- 1.4 and 39.8 +/- 3.8 PMN/field, respectively), which in both cases was inhibited by anti-CD18 monoclonal antibody (mAb) IB4. Stimulation of PMNs with PMA or OZ produced injury to 73% and 53% of BPAEC examined, respectively, which corresponded to 6.8-fold and 3.5-fold increases in transendothelial 125I-albumin permeability from baseline. Pretreatment of PMNs with mAb IB4 prevented endothelial injury in both cases. Both PMA and OZ increased the production of O2- (by 7.6-fold and 3.1-fold over control, respectively) and promoted the release of myeloperoxidase (5.2-fold and 9.1-fold over control, respectively) (P < .01). IB4 did not inhibit the PMA- or OZ-induced increases in O2-. IB4 did not inhibit the PMA-induced myeloperoxidase release but reduced by approximately 29% the OZ-induced myeloperoxidase release. Stimulation of PMNs layered on BPAEC with OZ (0.5 mg/ml) caused an approximately 7-fold increase in PMN [Ca2+]i over baseline, which decayed to a steady-state level above baseline at 10 min. IB4 (10 micrograms/ml) alone did not alter baseline [Ca2+]i and did not inhibit the OZ-induced increase in [Ca2+]i. In contrast to OZ, stimulation of PMNs with PMA did not increase [Ca2+]i. The results indicate that the protective effects of the anti-CD18 mAb IB4 were associated predominantly with its antiadherence property. Therefore, CD18 integrin-mediated PMN adhesion to the endothelium is a critical determinant of endothelial injury irrespective of the PMN-activating stimulus.

Exploring child dental service use among migrant families in metropolitan Melbourne, Australia.

BACKGROUND: This study describes and explores factors related to dental service use among migrant children. METHODS: A cross-sectional analysis of baseline data from Teeth Tales, an exploratory trial implementing a community based child oral health promotion intervention. The sample size and target population was 600 families with 1-4 year old children from Iraqi, Lebanese and Pakistani backgrounds residing in metropolitan Melbourne. Participants were recruited into the study using purposive and snowball sampling techniques. RESULTS: Most (88%; 550/625) children had never visited the dentist (mean (SD) age 3.06 years (1.11)). In the fully adjusted model the variable most significantly associated with child dental visiting was parent reported 'no reason for child to visit the dentist' (OR = 0.07, p < 0.001). Of those children whose parents reported their child had no reason to visit the dentist, 22% (37/165) experienced dental caries with 8% (13/165) at the level of cavitation. CONCLUSIONS: Dental service use by migrant preschool children was very low. The relationship between perceived dental need and dental service use is currently not aligned. One in 10 children of select migrant background had visited a dentist, which is in the context of 1 in 3 with dental caries. To improve utilization, health services should consider organizational cultural competence, outreach and increased engagement with the migrant community.

The identification and expression of heme oxygenase-2 alternative transcripts in the mouse.

Murine heme oxygenase-2 (HO-2) cDNA sequences were determined through the assembly of mouse expressed sequence tag (EST) sequences using the rat HO-2 sequence as a template. The sequence analysis revealed two mRNA isoforms, probably arising through alternative splicing, which differed in their 5'-untranslated region (UTR), and were named HO-2a and HO-2b. One EST sequence included an extended 3'-UTR and suggested there may be a choice of poly-adenylation (poly-A) signal sequence. Reverse transcriptase polymerase chain reaction (PCR) suggested that HO-2a mRNA may be specifically expressed in the testis, while HO-2b mRNA was present in all tissues analysed. Furthermore, HO-2a and HO-2b transcripts were both found to include the extended 3'-UTR, but these transcripts were detected only in the testis. Northern analysis of a greater range of tissues confirmed the testis-specific expression of HO-2a mRNA and suggested that the transcripts which included the extended 3'-UTR were a small minority of the HO-2 mRNA population. These alternative murine HO-2 transcripts suggest that mechanisms such as mRNA transport, translational efficiency or mRNA turnover may be implicated in the regulation of HO-2 gene expression, most notably in the testis.

Mn and Cu/Zn SOD expression in cells from LPS-sensitive and LPS-resistant mice.

We examined the effect of lipopolysaccharide (LPS) treatment on the expression of manganese and copper/zinc superoxide dismutase (MnSOD and Cu/ZnSOD) mRNA and protein in resident peritoneal macrophages and lung endothelial cells derived from LPS-sensitive (LPS-s) and LPS-resistant (LPS-r) mice. Macrophages from both LPS-s and LPS-r mice treated with LPS for 24 h produced increased levels of MnSOD mRNA and protein. In contrast, levels of lung endothelial cell MnSOD mRNA and protein from LPS-s mice were increased by LPS treatment, while no increases in these parameters were observed in endothelial cells from LPS-r mice. Tumor necrosis factor-alpha (TNF alpha) treatment, however, did increase levels of MnSOD mRNA in both LPS-s and LPS-r endothelial cells to an equal extent. Both macrophage and endothelial cell Cu/ZnSOD mRNA and protein levels were not significantly affected by LPS treatment. These results demonstrate that the mutation that affects susceptibility to LPS in LPS-r mice exerts a differential influence on MnSOD inducibility in a cell specific manner.

Double- and triple-labeling of functionally characterized central neurons projecting to peripheral targets studied in vitro.

The use of in vitro preparations such as brain slices poses difficulties in determining the correct identity of cells under study. To circumvent this problem, we first used a fluorescence pre-labeling technique (rhodamine-dextran-lysine) to identify cranial motoneurons projecting to the tongue (hypoglossal motoneurons) in the guinea-pig. Following preparation of slices, cells were recorded intracellularly and their electrophysiological properties determined. The cells were then intracellularly stained with both a fluorescence label (Lucifer Yellow) and with the stable, non-fading label biocytin. Under fluorescent illumination, the great majority of recorded cells within the hypoglossal nucleus were double-labeled (rhodamine and Lucifer Yellow) suggesting that most are indeed motoneurons. Biocytin injected into the same motoneurons provided permanent and detailed images of their morphology. Intracellularly stained cells surrounding the hypoglossal nucleus were not labeled with rhodamine and had distinct electro-physiological properties. The use of the retrogradely transported marker rhodamine-dextran-lysine allows the unambiguous identification of motoneurons in a brainstem slice. The combined intracellular injection of Lucifer Yellow and biocytin provides a simple means of melding the advantages of a fluorescent label (compatible with other fluorescence labels and with immunocytochemistry) with the benefits of a stable, non-fading, electron-dense marker. Application of this technique should prove useful in establishing morphological and functional correlates in other areas of the CNS.

Investigation of the functional role played by the chemokine monocyte chemoattractant protein-1 in interleukin-1-induced murine peritonitis.

1. Intraperitoneal (i.p.) injection of murine recombinant IL-1beta (mrIL-1beta) produced a dose-dependent (0.5-50 ng) and time-related (0.5-2 h) secretion of murine monocyte chemoattractant protein-1 (mMCP-1; 3-4 ng per cavity) in the lavage fluids. MCP-1 mRNA could also be detected in the cell pellets by reverse transcriptase-polymerase chain reaction (RT-PCR). 2. MCP-1 levels were reduced by more than 90% by co-administration of IL-1 receptor antagonist (10 microg) (n=6, P<0.05). In contrast, an IL-1 mutant with low affinity for IL-1 receptor type I, termed yIL-1betadelta4 (50 ng), produced only a modest release of the chemokine. Treatment of mice with dexamethasone (DEX) (approximately 1 mg kg(-1) s.c.) reduced mrIL-1beta-induced mMCP-1 gene expression (apparent total inhibition) and protein release in the lavage fluids (approximately 40% reduction; n=10; P<0.05). Drastic reductions in the numbers of residential macrophages or mast cells did not modify the levels of mMCP-1 recovered in the lavage fluids. 3. Injection of mrIL-1beta produced neutrophil accumulation into the peritoneal cavities (maximal at 4 h with 1.42+/-0.15 x 10(6) cells per mouse). Co-injection of a specific polyclonal antibody against mMCP-1 reduced this process by more than 50% (n=6; P<0.05). In conclusion, we studied the mechanisms leading to the specific release of the CC chemokine mMCP-1 after in vivo administration of mrIL-1beta.

Assessment of time-volume and flow-volume components of forced vital capacity. Measurement with spirometry, body plethysmography and respiratory inductive plethysmography in nonsmokers and smokers.

The purpose of this investigation was to assess the effectiveness of the time-volume and flow-volume components of the forced vital capacity measured by simultaneous spirometry, respiratory inductive plethysmography, and body plethysmography in detecting small airway disease. Spirometry measured the exit of gas from the lungs, whereas body plethysmography measured both the exit of gas and alveolar gas compression. Respiratory inductive plethysmography, which reflected change in thoracic volume, provided semi-quantitative data f both gas exit and alveolar gas compression which generally lay between spirometry and body plethysmography. In nine nonsmokers and 12 smokers (six with small airway disease as defined by abnormal closing volumes and alveolar uniformity), analysis of forced vital capacity revealed that the only test which differentiated nonsmokers from smokers was the higher spirometric estimation of maximum expiratory flow measured at 25 percent VC in nonsmokers. Combining flow measure at the mouth with volume referenced to change in alveolar gas volume as measured by body or respiratory inductive plethysmography did not differentiate nonsmokers from smokers. Moment analysis performed of forced vital capacity with all of the three devices did not distinguish nonsmokers from smokers. The data in this study and a review of other investigations indicate that the time-volume and flow-volume components of the forced vital capacity on air breathing are not very sensitive in detecting early lung disease in smokers.

Assessment of density dependent flow-volume parameters in nonsmokers and smokers. Measurement with spirometry, body plethysmography and respiratory inductive plethysmography.

The purpose of this investigation was to assess the density-dependent flow-volume components of the forced vital capacity using simultaneous spirometry, respiratory inductive plethysmography, and body plethysmography in the detection of small airway disease. The forced vital capacity was measured during air, helium-oxygen and sulfur-hexafluoride breathing to provide a range of gas density influences. Combining flow measured at the mouth with volume referenced to change in alveolar gas volume as measured by body or respiratory inductive plethysmography during helium-oxygen breathing accentuated the differences between nonsmokers and smokers because of the variable degree of alveolar gas compression occurring over the second half of FVC. The volume of isoflow obtained when comparing the helium and oxygen mixture to air also effectively separated nonsmokers from smokers. The utilization of the high density gas mixture, sulfur hexafluoride-oxygen during the FVC maneuver did not provide useful diagnostic information. Therefore, density-dependent flow-volume information using helium as a test gas alone or compared to air with a variety of analyses is a good approach to detection of early lung disease in smokers.

Substance P and NMDA receptor-mediated slow potentials in neonatal rat spinal cord: age-related changes.

Slow ventral root potentials (slow VRP's) recorded from 1- to 5-day-old rat spinal cords are implicated in nociception, but there is controversy over their origin and persistence in the adult. The present study investigated changes in the role of substance P and NMDA receptors in slow VRP generation during the postnatal period (1-21 days). Through 9 days, dorsal root stimulation elicits slow VRP's with typical peak amplitudes at 3-4 s, decay time constants of 18-20 s, and durations > 20 s. After 11 days, peak amplitude shortens to < 1 s, decay time constant 4-5 s, and duration < 10 s. At 1-6 days, slow VRP's are sensitive to the NMDA receptor antagonist APV and the substance P antagonists spantide and CP 96,345. After 11 days, APV sensitivity is retained, but spantide and ability of substance P to evoke a response are diminished. Abbreviated slow VRP's in post-11-day spinal cords appear to correspond to the early APV-sensitive component of long-duration slow VRP's in younger animals. Attempts to restore long-duration slow VRP's in 12- to 14-day-old rat cords by blocking various inhibitory mechanisms were not successful. The results suggest that a substance P response, some of which is mediated by NK1 receptors, is lost with maturation of the cord. Either a developmental role played by substance P changes with maturity, or the motor neurons of the isolated post-11-day cord lose the capacity to sustain large long-duration plateau potentials.

Correlates of anesthetic properties in isolated spinal cord: cyclobutanes.

Two halogenated cyclobutanes, one anesthetic and one not, were compared on receptor-specific pathways in isolated neonatal rat spinal cord. The anesthetic 1-chloro-1,2,2-trifluorocyclobutane depressed the monosynaptic reflex (glutamate non-NMDA receptors) and abolished a slow ventral root potential (glutamate NMDA, non-NMDA and tachykinin receptors). This compound slightly enhanced the muscimol-evoked dorsal root potential (GABAA) but reversibly depressed the dorsal root potential elicited by dorsal root stimulation. The non-anesthetic 1,2-dichlorohexafluorocyclobutane increased monosynaptic reflex, depressed slow ventral root potential approximately 50%, had little effect on muscimol-evoked dorsal root potential, and irreversibly depressed dorsal root-evoked dorsal root potential. Hypoxia accounts for slow ventral root potential depression, but not monosynaptic reflex enhancement. In this preparation and for this pair of compounds, anesthetic properties are related to blockade of transmission at glutamate synapses, with a small component of GABAA enhancement. Monosynaptic reflex increase may be related to the non-anesthetic cyclobutane's convulsant and anti-anesthetic properties.