The vectorcardiogram in mitral valve disease

The Frank system vectorcardiogram has been studied in 61 patients with severe mitral valve disease to determine the value of the vectorcardiogram in the recognition of the relative degree of left and right ventricular hypertrophy in this situation.     

Atrioventricular node reentry: Intravenous verapamil as a method of defining multiple electrophysiologic types

Fourteen patients with recurrent supraventricular tachycardia (SVT) underwent electrophysiological evaluation. Each patient was shown to have reentry confined to the region of the atrioventricular (AV) node. Verapamil, 0.075 to 0.15 mg/kg was administered intravenously to each patient during a stable episode of SVT, resulting in termination in each instance. There was more than one mechanism for termination of SVT. Nine patients showed termination by anterograde AV node block preceded by an increase in conduction time in the anterograde limb of the tachycardia circuit (Ae-H intervals) with no change in the conduction time in the retrograde limb (H-Ae intervals). Three patients showed termination by block in the retrograde limb of the circuit preceded by increases in both Ae-H and H-Ae intervals. An additional example of termination by spontaneous ventricular premature complexes and usurpation by sinus rhythm were also seen. Common features were that verapamil had significant effects on anterograde and retrograde conduction and refractoriness in the AV node. It prolonged the refractory periods of both fast and slow pathways in patients with dual anterograde AV node pathways, and observable effects on retrograde conduction and refractoriness were seen even in patients with constant ventriculoatrial conduction times during incremental ventricular pacing in a control study. However, three distinct groups of patients were identified on the basis of their response to ventricular pacing in a control study and upon verapamil effects recorded during their SVT. An explanation for these latter findings may be that there is a normal variation in the retrograde response of parts of the AV node to ventricular pacing, and a variability in some of the patients' responses to verapamil.     

Transduction of a bacterial gene into mammalian cells.

The transduction of an Escherichia coli gene into mammalian cells is described. A supressor tRNA gene was linked to a simian virus 40 (SV40) vector in vitro and the recombinant was used to transfect rat embryo cells and monkey kidney cells. The hybrid SV40 genome, SV40-su+ III, retained genetic information required for autonomous replication and cellular transformation and had a 1300-base-pair DNA segment in the late gene region (between the restriction endonuclease sits Hpa II at 0.735 and EcoRI at 0/1.0 on the SV40 genetic map) replaced by an 870-base-pair bacterial DNA segment containing the suppressor tRNA gene, su+ III (tRNATyrsu+III). The structure and fate of the SV40-su+III chimera were determined by DNA reassociation kinetic analysis and restriction enzyme cleavage of the total cellular DNA from transformed rat embryo cells and persistently infected monkey cells. Hybridization with radiolabeled probes specific for vector (SV40) or su+III DNA sequences revealed primarily nonintegrated or free hybrid genomes. In cloned lines of both cell types, the bacterial DNA segment was recovered intact, as judged by the length of the segment excised by restriction endonucleases and its ability to hybridize to the radiolabeled bacterial DNA probe and not to the SV40 probe.     

Surgical management of epilepsy due to cerebral cavernomas using neuronavigation and intraoperative MR imaging

OBJECTIVES： Cure from seizures due to cavernomas might be surgically achieved dependent on both, the complete removal of the cavernoma as well as its surrounding hemosiderin rim. High field intraoperative MRI imaging （iopMRI） and neuronavigation might play a crucial role to achieve both goals. We retrospectively investigated the long-term results and impact of intraoperative 1.5T MRI （iopMRI） and neuronavigation on the completeness of surgical removal of a cavernous malformation （CM） and its perilesional hemosiderin rim as well as reduction of surgical morbidity.     

Gender-Specific Associations of Objective and Perceived Neighborhood Characteristics With Body Mass Index and Waist Circumference Among Older Adults in the English Longitudinal Study of Ageing

Objectives. We sought to determine whether objective and perceived neighborhood characteristics are independently associated with obesity indicators among older adults and whether associations differ by gender.Methods. Linear regression was used to examine mutually adjusted associations of objective area-level neighborhood deprivation and perceived individual-level neighborhood disorder in 2002–2003 with body mass index (BMI) and waist circumference (WC) 2 years later among 6297 community-dwelling older adults in the English Longitudinal Study of Ageing.Results. Associations between neighborhood characteristics and obesity indicators were evident for women only. Being in the most deprived quintile of neighborhood deprivation was associated with a BMI that was 1.18 kilograms per meters squared higher (95% confidence interval [CI] = 0.54, 1.83) and a WC that was 2.42 centimeters higher (95% CI = 0.90, 3.94) at follow-up in women after adjustment for baseline health status, socioeconomic factors, and neighborhood disorder. Neighborhood disorder was not independently associated with BMI or WC.Conclusions. Among women, greater objective neighborhood deprivation was independently associated with higher BMI and WC after 2 years. Public efforts to reduce obesity among community-dwelling older women may benefit most from addressing objective residential characteristics, over and above subjective perceptions.Obesity increases the risk of heart disease, type 2 diabetes, stroke, and some types of cancer,1 making it an important condition to prevent and manage for any population. According to 2012 estimates, one third of men and women in England between 65 and 74 years of age are considered obese, the highest percentages of any age group.2 Although in general, levels of obesity (as measured via body mass index [BMI]) decrease after the age of 75 years, levels of abdominal adiposity (as measured via waist circumference [WC]) continue to increase with advancing age, particularly among women.2 With a 39% increase among individuals aged 65 to 84 years and a 106% increase among those older than 85 years expected from 2012 to 2032 in England alone,3,4 it is increasingly important to build a broader understanding of obesity risk at older ages.Obesity may be best understood within the context of its wider environmental influences.5 Older adults may restrict much of their daily life activity to their residential environment, as a result of either retirement or functional limitations, and may consequently be more influenced by these surroundings than younger adults.6 Thus, examining aspects of neighborhood environments may increase our understanding of obesity risk among older adults in particular.Although definitions vary, a neighborhood is broadly regarded as the area immediately surrounding one’s place of residence, measured either objectively at the area level through census data or predefined boundaries, or subjectively at the individual level through self-reported perceptions.7 Objective neighborhood characteristics associated with an individual’s obesity risk include residential density, walkability, presence of graffiti, local access to recreational facilities, presence of green space and supermarkets, and inadequate housing; unfavorable levels of these characteristics may together form a concept known as “neighborhood deprivation.”8,9 Associations between objective neighborhood factors and obesity risk have been shown to be gender-specific. For instance, one study showed that women living in the most deprived areas of the United Kingdom had a higher baseline BMI than those living in the least deprived areas and exhibited greater BMI increases over 13 years,10 whereas these associations were not evident among men.By contrast, subjective neighborhood characteristics may include individual perceptions of built attributes, interpersonal relationships, or safety. A subjective general construct known as “neighborhood disorder” aims to capture perceptions of both physical and social factors by incorporating dimensions such as safety, trust of neighbors, vandalism, and area cleanliness11; thus, this construct may include neighborhood characteristics that are particularly salient for the individual. Greater neighborhood disorder has been associated with higher levels of obesity indicators such as waist-to-hip ratio11 and BMI.12Despite the fact that both area-level objective and individual-level perceived aspects of neighborhoods demonstrate associations with obesity risk, the independence of these associations is unknown. Furthermore, their relevance to older populations and their gender-specific nature have not been established. Evidence also suggests that effects on obesity indicators may differ. For instance, objective neighborhood deprivation has been associated with higher BMI,10 whereas subjective neighborhood disorder has been associated with both higher BMI12 and higher central adiposity.11It would be useful to examine effects of neighborhood measures on separate indicators of obesity to understand which aspects are most strongly associated with obesity risk and, thus, the areas in which efforts to intervene would be best directed. In this study, involving a large sample of community-dwelling older adults in England, we sought to determine whether area-level objective neighborhood characteristics and individual-level subjective perceptions of the neighborhood environment are associated with obesity indicators independently of one another and whether these associations are gender-specific.     

The Oregon Child Absenteeism Due to Respiratory Disease Study (ORCHARDS): Rationale,objectives, and design

BackgroundInfluenza viruses pose significant disease burdens through seasonal outbreaks and unpredictable pandemics. Existing surveillance programs rely heavily on reporting of medically attended influenza (MAI). Continuously monitoring cause‐specific school absenteeism may identify local acceleration of seasonal influenza activity. The Oregon Child Absenteeism Due to Respiratory Disease Study (ORCHARDS; Oregon, WI) implements daily school‐based monitoring of influenza‐like illness‐specific student absenteeism (a‐ILI) in kindergarten through Grade 12 schools and assesses this approach for early detection of accelerated influenza and other respiratory pathogen transmission in schools and surrounding communities.MethodsStarting in September 2014, ORCHARDS combines automated reporting of daily absenteeism within six schools and home visits to school children with acute respiratory infection (ARI). Demographic, epidemiological, and symptom data are collected along with respiratory specimens. Specimens are tested for influenza and other respiratory viruses. Household members can opt into a supplementary household transmission study. Community comparisons are possible using a pre‐existing and highly effective influenza surveillance program, based on MAI at five family medicine clinics in the same geographical area.ResultsOver the first 5 years, a‐ILI occurred on 6634 (0.20%) of 3,260,461 student school days. Viral pathogens were detected in 64.5% of 1728 children with ARI who received a home visit. Influenza was the most commonly detected virus, noted in 23.3% of ill students.ConclusionORCHARDS uses a community‐based design to detect influenza trends over multiple seasons and to evaluate the utility of absenteeism for early detection of accelerated influenza and other respiratory pathogen transmission in schools and surrounding communities.     

Acute intranasal osteopontin treatment in male rats following TBI increases the number of activated microglia but does not alter lesion characteristics

Intranasal recombinant osteopontin (OPN) has been shown to be neuroprotective in different models of acquired brain injury but has never been tested after traumatic brain injury (TBI). We used a model of moderate-to-severe controlled cortical impact in male adult Sprague Dawley rats and tested our hypothesis that OPN treatment would improve neurological outcomes, lesion and brain tissue characteristics, neuroinflammation, and vascular characteristics at 1 day post-injury. Intranasal OPN administered 1 hr after the TBI did not improve neurological score, lesion volumes, blood–brain barrier, or vascular characteristics. When assessing neuroinflammation, we did not observe any effect of OPN on the astrocyte reactivity but discovered an increased number of activated microglia within the ipsilateral hemisphere. Moreover, we found a correlation between edema and heme oxygenase-1 (HO-1) expression which was decreased in OPN-treated animals, suggesting an effect of OPN on the HO-1 response to injury. Thus, OPN may increase or accelerate the microglial response after TBI, and early response of HO-1 in modulating edema formation may limit the secondary consequences of TBI at later time points. Additional experiments and at longer time points are needed to determine if intranasal OPN could potentially be used as a treatment after TBI where it might be beneficial by activating protective signaling pathways.