Neighbourhood influence on the fourth dose of diphtheria-tetanus-pertussis vaccination.

OBJECTIVES: Using 542,159 vaccination records from children born between April 1, 2007, and March 31, 2012, in the Michigan Care Improvement Registry and data from the American Community Survey, we determine if neighbourhood-level characteristics at the Census tract level and block level are associated with low uptake of the fourth dose of diphtheria-tetanus-acellular pertussis vaccine (DTaP4). STUDY DESIGN: This study was a cross-sectional study. METHODS: We used exploratory factor analysis to determine important socio-economic factors at the Census block level and tract level. We then used generalised estimating equations to test the relationship between block- and tract-level socio-economic factors and DTaP4 uptake. RESULTS: DTaP4 coverage was 88.6% (95% confidence interval [CI]: 88.4%-88.7%) in Michigan. At the Census tract level, two factors surfaced as important for DTaP4 vaccination: 'affluence' (Cronbach's alpha = 0.88) and 'socio-economic disadvantage' (Cronbach's alpha = 0.89). At the Census block level, one factor was important: 'affluence' (Cronbach's alpha = 0.90). Affluence may relate to knowledge about medical exemptions and antivaccination sentiment, while socio-economic disadvantage may indicate limited access to healthcare resources. Children in high-affluence tracts had 1.08% lower vaccination coverage (95% CI: -1.62% to -0.55%) than children in low affluence tracts. Children in low socio-economic disadvantage tracts had 2.92% higher coverage than children in high socio-economic disadvantage tracts (95% CI: 2.58%-3.26%). CONCLUSIONS: This study articulates the need to further understand the contribution of neighbourhood-level characteristics, from both affluent and socioeconomically disadvantaged areas to low vaccination rates. Developing a better understanding of these social environmental factors will help determine useful community-level interventions to improve vaccination rates and reduce disease burden.

Latent variable modeling to develop a robust proxy for sensitive behaviors: application to latrine use behavior and its association with sanitation access in a middle-income country.

BACKGROUND: Globally, diarrhea is a leading cause of child morbidity and mortality. Although latrines are integral for reducing enteric pathogen transmission, several studies have shown no evidence that latrine ownership improved child health. There are a number of explanations for these results. One explanation is that latrine access does not equate to latrine use. Latrine use, however, is difficult to accurately ascertain, as defecation behavior is often stigmatized. To address this measurement issue, we measure latrine use as a latent variable, indicated by a suite of psychosocial variables. METHODS: We administered a survey of 16 defecation-related psychosocial questions to 251 individuals living in rural Ecuador. We applied latent class analysis (LCA) to these data to model the probability of latrine use as a latent variable. To account for uncertainty in predicted latent class membership, we used a pseudo-class approach to impute five different probabilities of latrine use for each respondent. Via regression modeling, we tested the association between household sanitation and each imputed latrine use variable. RESULTS: The optimal model presented strong evidence of two latent classes (entropy = 0.86): consistent users (78%) and inconsistent users (22%), predicted by 5 of our 16 psychosocial variables. There was no evidence of an association between the probability of latrine use, predicted from the LCA, and household access to basic sanitation (OR = 1.1, 95% CI = 0.6-2.1). This suggests that home access to a sanitation facility may not ensure the use of the facility for every family member at all times. CONCLUSION: Effective implementation and evaluation of sanitation programs requires accurate measurement of latrine use. Psychosocial variables, such as norms, perceptions, and attitudes may provide robust proxy-measures. Future longitudinal studies will help to strengthen the use of these surrogate measures, as many of these factors may be subject to secular trends. Additionally, subgroup analyses will elucidate how our  proxy indicators of latrine defecation vary by individual-level characteristics.

Muscle Weakness and Physical Disability in Older Americans: Longitudinal Findings from the U.S. Health and Retirement Study.

IMPORTANCE: Muscle weakness is an important indicator of disability, chronic disease and mortality. While we recently proposed sex/race specific grip strength cutpoints for clinical muscle weakness in a diverse, nationally representative sample of older Americans, the extent to which these cutpoints predict physical disability remains unknown. OBJECTIVE: To examine whether sex/race specific muscle weakness cutpoints predict physical disability status in a nationally representative sample of Americans age 65+. DESIGN: We used data from the 2006-2010 Health and Retirement Study. Fully-adjusted, weighted multinomial logistic regression models were used to quantify the odds of experiencing the onset, progression or persistence of disability in activities of daily living (ADL) among weak versus non-weak individuals over a 2-year period. SETTING: General community, nationally representative sample of older Americans. PARTICIPANTS: Population-based, community dwelling sample of older American adults aged 65-years+; 57 percent were women, 91% were White and the mean age was 75 years. Main Outcome(s) and Measure(s): The primary outcome of interest was disability dynamics, defined by changes in ADL status across at 2- year period. The primary exposure was clinical muscle weakness as defined by previously identified cutpoints. Hypotheses were formulated before analyses were conducted. RESULTS: In this nationally representative sample (n= 8,725), 44% of individuals were classified as weak at baseline. At follow-up, 55% remained independent with no change in their ADL status, 11% had an onset of disability and 4% progressed in their disability status. The odds of experiencing an onset of ADL disability was 54% higher among weak individuals compared those who were not weak at baseline (OR= 1.54, 95% CI= 1.54, 1.5, p<.0001); the odds of experiencing a progression in physical disability status was 2.16 times higher among those who were weak at baseline compared to non-weak individuals (OR= 2.16, 95% CI= 2.15, 2.16, p<.0001). CONCLUSIONS: This is the first study to use grip strength weakness cut-points to identify those who may be at greatest risk for experiencing physical disability in later life. Results underscore the importance of using population-specific cutpoints for clinical weakness in order to identify individuals at greatest risk for adverse health outcomes.

Self-efficacy, neighborhood walking, and fall history in older adults.

This cross-sectional study examined the association of self-efficacy with neighborhood walking in older adult (mean age = 76.1, SD = 8.34) fallers (n = 108) and nonfallers (n = 217) while controlling for demographic characteristics and mobility. Hierarchical multiple regression indicated that the full model explained 39% of the variance in neighborhood walking in fallers (P < .001) and 24% in nonfallers (P < .001). Self-efficacy explained 23% of the variance in fallers (P < .001) and 11% in nonfallers (P < .001). Neighborhood walking was significantly associated with self-efficacy for individual barriers in both groups. Self-efficacy for neighborhood barriers trended toward significance in fallers (ß = .18, P = .06). Fall history did not moderate the relationship between self-efficacy and neighborhood walking. Walking interventions for older adults should address self-efficacy in overcoming individual walking barriers. Those targeting fallers should consider addressing self-efficacy for overcoming neighborhood barriers.

Resprouting as a key functional trait: how buds, protection and resources drive persistence after fire.

Resprouting as a response to disturbance is now widely recognized as a key functional trait among woody plants and as the basis for the persistence niche. However, the underlying mechanisms that define resprouting responses to disturbance are poorly conceptualized. Resprouting ability is constrained by the interaction of the disturbance regime that depletes the buds and resources needed to fund resprouting, and the environment that drives growth and resource allocation. We develop a buds-protection-resources (BPR) framework for understanding resprouting in fire-prone ecosystems, based on bud bank location, bud protection, and how buds are resourced. Using this framework we go beyond earlier emphases on basal resprouting and highlight the importance of apical, epicormic and below-ground resprouting to the persistence niche. The BPR framework provides insights into: resprouting typologies that include both fire resisters (i.e. survive fire but do not resprout) and fire resprouters; the methods by which buds escape fire effects, such as thick bark; and the predictability of community assembly of resprouting types in relation to site productivity, disturbance regime and competition. Furthermore, predicting the consequences of global change is enhanced by the BPR framework because it potentially forecasts the retention or loss of above-ground biomass.

Ductal carcinoma in situ of the male breast presenting as adolescent unilateral gynaecomastia.

A 17 year old male patient was referred to the breast surgery service with a unilateral swelling of the left breast. Subsequent evaluation led to discharge with a diagnosis of adolescent gynaecomastia. Four years later the same patient was referred back to the breast surgery service and the referral was turned down without a consultation as the surgical treatment of gynaecomastia was not funded by the local Primary Care Trust (PCT). Three years following, this now 24 year old gentleman was referred to the Plastic surgery service at the Hospital Trust where he had been initially referred as a 17 year old. He underwent a nipple sparing mastectomy through a peri-areolar incision. The histology amounted to a diagnosis of ductal carcinoma in situ (DCIS). A literature review revealed the rarity of pure DCIS in the adolescent male. The variation in availability of treatments across the National Health Service in England has lead to a "postcode lottery" due to "rationing" decisions being made by individual Primary Care Trusts. "Action on Plastic Surgery", an NHS Modernisation Agency document, was designed as an aid to PCT's making funding decisions on Plastic Surgery patients in 2005. The case described in this report illustrates the difficulty in clinical diagnosis of a male breast lump. This persistent lesion was sampled on 2 separate occasions with fine needle aspiration, neither aspirate raising the possibility of DCIS. In conclusion this case describes a rare pre-malignant condition of the male breast. Complete histology of such a lump is the only conclusive investigation necessary and the limitations put upon the surgeon by the "rationing" of such treatment must be overcome on clinical grounds.

Accessing and selecting word meaning in autism spectrum disorder.

BACKGROUND: Comprehension difficulties are commonly reported in autism spectrum disorder (ASD) but the causes of these difficulties are poorly understood. This study investigates how children with ASD access and select meanings of ambiguous words to test four hypotheses regarding the nature of their comprehension difficulties: semantic deficit, weak central coherence, reduced top-down control and inhibition deficit. METHODS: The cross-modal semantic priming paradigm was used. Children heard homonym primes in isolation or as final words in sentences biased towards the subordinate meaning and then named picture targets depicting dominant or subordinate associates of homonyms. RESULTS: When homonyms were presented in isolation, children with ASD and controls showed priming for dominant and subordinate pictures at 250ms ISI. At 1,000ms ISI, the controls showed dominant (but not subordinate) priming whilst the ASD group did not show any priming. When homonyms were presented in subordinate sentence contexts, both groups only showed priming for context-appropriate (subordinate) meanings at 250ms ISI, suggesting that context has an early influence on meaning selection. At 1,000ms ISI the controls showed context-appropriate (but not inappropriate) priming whereas the ASD group showed both appropriate and inappropriate priming. CONCLUSIONS: Children with ASD showed intact access to semantic information early in the time course of processing; however, they showed impairments in the selection of semantic representations later in processing. These findings suggest that a difficulty with initiating top-down strategies to modulate online semantic processing may compromise language comprehension in ASD. Implications for intervention are discussed.

Fire season and intensity affect shrub recruitment in temperate sclerophyllous woodlands.

The season in which a fire occurs may regulate plant seedling recruitment because of: (1) the interaction of season and intensity of fire and the temperature requirements for seed release, germination and growth; (2) post-fire rainfall and temperature patterns affecting germination; (3) the interaction of post-fire germination conditions and competition from surrounding vegetation; and (4) the interaction of post-fire germination conditions and seed predators and/or seedling herbivores. This study examined the effects of different fire intensities and fire seasons on the emergence and survival of shrubs representing a range of fire response syndromes from a summer rainfall cool climate region. Replicated experimental burns were conducted in two seasons (spring and autumn) in 2 consecutive years and fuel loads were increased to examine the effects of fire intensity (low intensity and moderate intensity). Post-fire watering treatments partitioned the effects of seasonal temperature from soil moisture. Higher intensity fires resulted in enhanced seedling emergence for hard-seeded species but rarely influenced survival. Spring fires enhanced seedling emergence across all functional groups. Reduced autumn recruitment was related to seasonal temperature inhibiting germination rather than a lack of soil moisture or competition. In Mediterranean-type climate regions, seedling emergence has been related to post-fire rainfall and exposure of seeds to seed predators. We think a similar model may operate in temperate summer rainfall regions where cold-induced dormancy over winter exposes seeds to predators for a longer time and subsequently results in recruitment failure. Our results support the theory that the effect of fire season is more predictable where there are strong seasonal patterns in climate. In this study seasonal temperature rather than rainfall appears to be more influential.

Fusion of contrast-enhanced breast MR and mammographic imaging data.

Increasing use is being made of Gd-DTPA contrast-enhanced MRI (CE-MRI) for breast cancer assessment since it provides three-dimensional (3D) functional information via pharmacokinetic interaction between contrast agent and tumour vascularity, and because it is applicable to women of all ages as well as patients with post-operative scarring. CE-MRI is complementary to conventional X-ray mammography, since it is a relatively low-resolution functional counterpart of a comparatively high-resolution 2D structural representation. However, despite the additional information provided by MRI, mammography is still an extremely important diagnostic imaging modality, particularly for several common conditions such as ductal carcinoma in situ (DCIS) where it has been shown that there is a strong correlation between microcalcification clusters and malignancy. Pathological indicators such as calcifications and fine spiculations are not visible in CE-MRI and therefore there is clinical and diagnostic value in fusing the high-resolution structural information available from mammography with the functional data acquired from MRI. This article is a clinical overview of the results of a technique to transform the coordinates of regions of interest (ROIs) from the 2D mammograms to the spatial reference frame of the contrast-enhanced MRI volume. An evaluation of the fusion framework is demonstrated with a series of clinical cases and a total of 14 patient examples.

Rapid deposition of wheat cell wall structural proteins in response to Fusarium-derived elicitors.

Two novel cell wall structural proteins of spring wheat (Triticum aestivum L. em Thell.). undergo rapid deposition in the cell wall matrix in a H(2)O(2)-dependent reaction after the elicitation of cultures with Fusarium graminearum (L.)-derived elicitor. The amino acid compositions of these proteins were remarkably similar and indicated that they were highly acidic (pI 3.8). These proteins contained 13--17% each of Gly, Glx and Ser with lesser amounts (6--8%) of Ala, Asx and Thr, and it has been suggested that they are known as glycine- and serine-rich proteins (GSRPs). SELDI-MS ionization spectra demonstrated that these proteins have low molecular masses of 8590 and 4292 Da. These results are discussed in relation to the possible role of these novel proteins in rapid, cell wall defensive reactions to pathogenic attack.

Measuring psychological well-being in the Canadian Study of Health and Aging.

The Canadian Study of Health and Aging (CHSA) provided an opportunity to examine the positive aspects of aging. CHSA-2 included the 18-item Ryff multidimensional measure of well-being, which taps six core theoretical dimensions of positive psychological functioning. The measure was administered to 4,960 seniors without severe cognitive impairment or dementia at CSHA-2. Intercorrelations across scales were generally low. At the same time, the internal consistency reliability of each of the 6 subscales was not found to be high. Confirmatory factor analyses provide support for a 6-factor model, although some items demonstrate poor factor loadings. The well-being measures in CSHA-2 provide an opportunity to examine broad, descriptive patterns of well-being in Canadian seniors.

Changes in quality of life over the first year after stroke: findings from the Sunnybrook Stroke Study.

PURPOSE: The purpose of this study was to investigate the longitudinal patterns of recovery of quality of life over the first year after stroke to understand the factors that are influential in this process. METHOD: A sample of 116 stroke survivors with mild to moderate impairment was followed-up at 3 months and at 1 year after stroke onset. Changes in scores on a quality of life measure were assessed in association with changes in impairment and disability over this 9-month period. The use of rehabilitation services over the first year was also documented. RESULTS: The quality of life of these survivors improved over the first year after stroke. Improvements in motor disability and depressive symptoms were found to be associated with improvements in quality of life. Additionally, survivors receiving rehabilitation therapy reported an improvement in quality of life that was independent of changes in disability and depressive symptoms. CONCLUSIONS: Opportunities to enhance the quality of life of stroke survivors exist throughout the first year of recovery. Improvements in functional ability and depression are important for long-term improvements in quality of life. Rehabilitation therapy is a potentially important resource.

An improved mouse sperm-oocyte plasmalemma binding assay: studies on characteristics of sperm binding in medium with or without glucose.

Sperm binding to the oocyte plasmalemma is crucial to subsequent steps in fertilization. However, the usual in vitro assay for sperm-oocyte binding does not distinguish between nonspecific attachment and specific binding leading to fusion and penetration. Since zona pellucida-free pronuclear zygotes should not bind sperm (because of the block to polyspermy at the level of the oocyte membrane), a procedure has been developed to remove virtually all sperm from zona-free pronuclear zygotes (2PNZ). After six washes with a 90-microm-bore pipette, there were 0.5 +/- 0.2 sperm/2PNZ (n = 83). Therefore, these washing conditions were used to define sperm-oocyte binding. The relationship of binding to oocyte penetration was determined for outbred mouse oocytes coincubated in complete medium with (B6 x 129)F1 hybrid sperm (10(7)/ml). Binding was maximal (29 +/- 5 sperm per oocyte) during the first 30 minutes but decreased significantly to 4.6 +/- 1.4 by 60 minutes of coincubation (over 10 trials). Oocyte penetration was 99 +/- 1% by 30 minutes, while the number of decondensed sperm nuclei per oocyte increased significantly to 7.5 +/- 0.6 at 60 minutes. These data suggest that the block to polyspermy involves detachment of bound sperm. Similar coincubations were carried out in medium without glucose (NoG), as this medium has been reported to inhibit fusion without affecting binding. However, binding was only 11 +/- 2 at 30 minutes but increased to 25 +/- 4 at 60 minutes, suggesting that binding was retarded in NoG. When gametes were coincubated in NoG for 5 hours, about half of the oocytes were penetrated, suggesting that the lack of glucose did not inhibit fusion but instead delayed it. These data suggest that if sperm binding is to be determined in complete medium, the time of the block to polyspermy should be determined prior to selecting the appropriate time to assay binding. Furthermore, using the same coincubation period for the binding assay in control and treated sperm may not be appropriate if the treatment alters the time of maximal binding.

Handicap in stroke survivors.

BACKGROUND AND PURPOSE: As survival following stroke improves, individuals are more likely to live with the aftermath of stroke rather than immediately die from it. The purpose of this study was to examine the consequences of stroke on the life activities of survivors in the social realm (stroke handicap) using the framework of the World Health Organization's International Classification of Impairments, Disabilities and Handicaps. METHODS: Multivariate analysis of variance was applied to cross-sectional data from a clinical study to investigate the correlates of handicap in a cohort of hemispheric stroke survivors at 3 months (n = 145) and at 1 year (n = 135) after stroke onset. Handicap was assessed with the Reintegration to Normal Living Index, impairment by the Adams' Hemispheric Stroke Scale and Zung Depression Scale, and disability by the Functional Independence Measure. Environmental variables in the model included marital status and receipt of rehabilitation therapy. RESULTS: Physical disability and post-stroke depressive symptoms were associated with handicap at both follow-up periods (p < 0.05). Cognitive disability and impairments from a previous stroke were also associated with handicap (p < 0.01), but only at 1 year. The presence of a spouse was found to benefit male survivors at 1 year. CONCLUSIONS: Disability and depressive symptoms restrict the meaningful life activities of stroke survivors in the first year of recovery. Social supports may be influential in reducing their impact.

Allogeneic blood transfusion reduces murine pulmonary natural killer (NK) activity and enhances lung metastasis of a syngeneic tumour.

A model was established whereby C57BL/6 (B6) blood injected i.v. into C3H mice 7 days prior to i.v. injection of syngeneic UV-2237 tumour cells significantly increased the number of pulmonary metastases counted 21 days later as compared with levels observed in mice treated with saline, C3H or NZW blood or SRBC. This regimen of B6 allogeneic blood transfusion of C3H mice also significantly depressed splenic and pulmonary NK activity as assayed by lysis of 51Cr YAC-I in vitro and by clearance of 111In YAC-I in vivo respectively. Anti-asialo GMI treatment, which depletes NK activity in vivo, and Poly I:C treatment, which enhances NK activity in vivo, were associated with significantly increased and decreased pulmonary metastasis of UV-2237, respectively, in C3H mice. Depletion of CD4+ and CD8+ T cells had no effect. Cyclophosphamide pretreatment which, among other effects, depletes NK cells, significantly increased pulmonary metastasis of UV-2237 in C3H mice. This was corrected by adoptive transfer of normal C3H spleen cells but not spleen cells from anti-asialo GMI-treated C3H mice or B6-blood-transfused C3H mice. Furthermore, a 1:1 mixture of normal C3H spleen cells with spleen cells from B6-blood-transfused C3H mice also failed to reconstitute the cyclophosphamide-pre-treated C3H mice. We conclude that allogeneic blood transfusion augments pulmonary metastasis of the UV-2237 sarcoma in C3H mice and that the mechanism involves suppression of NK activity.

Factors that may regulate assembly of the mammalian sperm tail deduced from a mouse t complex mutation.

A unique pattern of aberrant sperm development occurs in laboratory mice (Mus domesticus) that have been made homozygous for an allele of an autosomal gene, Hst-6s, derived from another mouse species, Mus spretus. During the abnormal spermiogenic process of these sterile animals, the sperm tail fails to assemble normally, although a bud develops at the site of the centriole in early spermatids. The bud enlarges during sperm development and eventually contains elements of a mature sperm tail. Tubulin assembles primarily into single microtubules rather than doublets. These singlets form a circular array that is not oriented relative to the centriole. While dense fibers form in association with the singlet microtubules, the fibrous sheath components accumulate in a single irregular mass. These observations suggest that microtubule doublets are required for the organization of an axoneme. In addition, while dense fibers can form normally in association with singlet microtubules, the fibrous sheath requires the axoneme as a substrate for normal organization.