Evaluation of gastric motility in nine dogs before and after prophylactic laparoscopic gastropexy: a pilot study.

BACKGROUND: The purpose of this study was to evaluate the effect of a prophylactic laparoscopic gastropexy on gastric motility in healthy large-breed dogs. METHODS: This was a prospective pilot study with nine healthy client-owned dogs. Each dog was its own control. Gastric motility was evaluated before and after laparoscopic gastropexy. Dogs were fed a standard diet three weeks before and after surgery. Gastric motility was measured before and 3 weeks after surgery. A wireless motility capsule (WMC) was used to measure gastric pH, intragastric pressure, temperature, frequency of contractions, motility index (MI) and transit time. Non-parametric statistical analysis was used to compare the paired data. Clients were contacted for follow-up information 2 years postoperatively. RESULTS: Median frequency of gastric contractions was 1.3 (range, 0.6-1.9 contractions/min) before gastropexy and 1.0 (range, 0.3-2.6 contractions/min) after gastropexy (P = 0.820). Median MI was 49.2 (range, 23.7-96.6) before gastropexy and 28.1 (range, 12.2-148.9) after gastropexy (P = 0.652). Median gastric emptying time was 1140 (range, 486-1230 min) before gastropexy and 1110 (range, 306-2610 min) after gastropexy (P = 0.570). During the hour before the WMC passed through the pylorus, median MI was 72.2 (range, 48.2-549.3) before gastropexy and 52.9 (range, 15.20-322.8) after gastropexy (P = 0.734), and frequency of contractions was 1.1 (range, 0.9-4.1 contractions/min) before gastropexy and 1.2 (range, 0.5-3.0 contractions/min) after gastropexy (P = 0.652). CONCLUSION: Motility in the stomach did not change in healthy dogs after prophylactic laparoscopic gastropexy. We conclude that preventive laparoscopic gastropexy does not induce gastroparesis.

Familial breast cancer screening reveals an alteration in the RAP80 UIM domain that impairs DNA damage response function.

Germline mutations in two major susceptibility genes, BRCA1 and BRCA2, account for nearly 20% of familial breast cancers. A majority of the remaining genetic factors involved in heritable breast cancer susceptibility are, however, unknown. Recently, a new BRCA1-interacting protein, receptor associated protein 80 (RAP80), was identified. RAP80 plays an important role in BRCA1-mediated DNA damage responses (DDRs) by recruiting BRCA1 to DNA double-strand breaks (DSBs). A comprehensive screening of DNA from affected index cases of 112 BRCA1/BRCA2 mutation-negative Finnish breast cancer families revealed altogether 10 alterations in RAP80, one of which, c.241-243delGAA, resulted in a single glutamic acid deletion at residue 81 in a highly conserved region of ubiquitin interaction motif 1. The resultant delE81 protein product displayed significantly reduced ubiquitin binding and DSB localization. Expression of the RAP80 delE81 allele impaired both BRCA1 and ABRA1 DSB recruitment, thus compromising BRCA1-mediated DDR signaling. Compared with wild-type RAP80, expression of the delE81 allele was associated with a significant increase in cytogenetically detectable chromosomal aberrations, particularly chromatid breaks. Although evidently quite rare, these results suggest that critical constitutional mutations in RAP80 abrogate DDR function and may be involved in genetic predisposition to cancer.

Does the perireticular thalamic nucleus project to the neocortex?

This study defines several features of the early connections of the developmentally transient perireticular thalamic nucleus of rats. The neocortex of developing rats was injected with either DiI, biotinylated dextran, WGA-HRP (wheatgerm agglutinin conjugated-horseradish peroxidase), fluorescent latex beads or cholera toxin subunit B (CTB) and their brains were processed for tracer detection with standard methods. In general, tracer injections into various regions of the developing neocortex revealed no labelled neurones within the perireticular nucleus, although some of these tracers (WGA-HRP, dextran) labelled many of the amoeboid microglial cells that are found within this nucleus. There were, however, many retrogradely labelled neurones in a region adjacent to the perireticular nucleus, within the nucleus basalis of the basal forebrain (medial edge of globus pallidus). Their identity was confirmed as neurones of the nucleus basalis since they were all were similar in morphology and somal size to neurones that were immunoreactive to NGFr (nerve growth factor receptor), an antigen found only among neurones of the nucleus basalis and basal forebrain. Moreover, double labelling experiments revealed that most, if not all, of the cortically labelled neurones were NGFr-immunoreactive also. Thus, in conclusion, our results suggest that the perireticular nucleus does not project to the neocortex; the only neurones in the general vicinity of the perireticular nucleus that have a cortical projection form part of the nucleus basalis.

Topography of fibre organisation in the corticofugal pathways of rats.

The organisation of the long descending corticofugal pathways is poorly understood. We have examined these pathways to determine the fibre relationships along the extent of their course through the internal capsule, cerebral peduncle, longitudinal pontine fasciculus, pyramid, pyramidal decussation, and dorsal column of the spinal cord. Different cytoarchitectonic regions (e.g., lateral agranular and granular) of the rat's neocortex were injected with the axonal tracer biotinylated dextran. In other experiments, each animal had different-coloured fluorescent tracers (Fluoro Ruby and dextran-fluorescein) injected into separate cortical areas. Our results show that in the anterior and posterior limbs of the internal capsule, axons arising from spatially separate sites in rat neocortex occupy distinct regions of the cross-sectional area of the pathway. More caudally, within the cerebral peduncle and the longitudinal pontine fasciculus, axons from more distant cortical areas remain largely separate, but those from adjacent cortical areas begin to overlap. By the medullary pyramid, the pyramidal decussation, and the dorsal column of the spinal cord, the representations of all the cortical regions injected overlap completely; in these structures, the axons arising from each cortical area are widely intermingled. Thus, along the rostral-to-caudal course of the corticofugal pathways, there is a change in the organisation of axons. At rostral levels, the order corresponds roughly to the spatial distribution of the cells of origin, but more caudally, this changes to an arrangement of axons that has no readily apparent order. A similar change has been observed along the course of the retinofugal pathway, where a decrease of spatial order in the fibre distribution has been associated with a reordering of axons according to their temporal sequence of outgrowth.

Insights into dietary recall from a longitudinal study: accuracy over four decades.

We studied the validity and consistency of memory of foods consumed decades earlier in a longitudinal population of 91 persons. The memory of middle-aged persons for food intake years earlier did not decline invariably over time, although median correlations between actual and recalled consumption decreased. Time-related memory loss varied greatly from food to food. Neither analyses of group mean differences and SDs over all foods nor those for individual foods provided clearcut evidence of time-related memory loss. Systematic biases in memories of dietary intakes in the distant past were evident, depending on current diet and varying according to individual foods and food groups. These discrepancies may represent either misremembering or the effects of inferential processes. Examination of the consistency (reliability) and validity of reports of food intake indicated that validity estimates provided by mean differences between recalled and actual intakes were more revealing than correlation coefficient. Consistent reports were not necessarily valid, as indicated by memories of food intake. Correct inferences may have been made even when the actual memory was lost.

Organization of the visual reticular thalamic nucleus of the rat.

The visual sector of the reticular thalamic nucleus has come under some intense scrutiny over recent years, principally because of the key role that the nucleus plays in the processing of visual information. Despite this scrutiny, we know very little of how the connections between the reticular nucleus and the different areas of visual cortex and the different visual dorsal thalamic nuclei are organized. This study examines the patterns of reticular connections with the visual cortex and the dorsal thalamus in the rat, a species where the visual pathways have been well documented. Biotinylated dextran, an anterograde and retrograde tracer, was injected into different visual cortical areas [17; rostral 18a: presumed area AL: (anterolateral); caudal 18a: presumed area LM (lateromedial); rostral 18b: presumed area AM (anteromedial); caudal 18b: presumed area PM (posteromedial)] and into different visual dorsal thalamic nuclei (posterior thalamic, lateral geniculate nuclei), and the patterns of anterograde and retrograde labelling in the reticular nucleus were examined. From the cortical injections, we find that the visual sector of the reticular nucleus is divided into subsectors that each receive an input from a distinct visual cortical area, with little or no overlap. Further, the resulting pattern of cortical terminations in the reticular nucleus reflects largely the patterns of termination in the dorsal thalamus. That is, each cortical area projects to a largely distinct subsector of the reticular nucleus, as it does to a largely distinct dorsal thalamic nucleus. As with each of the visual cortical areas, each of the visual dorsal thalamic (lateral geniculate, lateral posterior, posterior thalamic) nuclei relate to a separate territory of the reticular nucleus, with little or no overlap. Each of these dorsal thalamic territories within the reticular nucleus receives inputs from one or more of the visual cortical areas. For instance, the region to the reticular nucleus that is labelled after an injection into the lateral geniculate nucleus encompasses the reticular regions which receive afferents from cortical areas 17, rostral 18b and caudal 18b. These results suggest that individual cortical areas may influence the activity of different dorsal thalamic nuclei through their reticular connections.

Evidence for a projection from the perireticular thalamic nucleus to the dorsal thalamus in the adult rat and ferret.

During early development, the perireticular thalamic nucleus is very large (i.e. has many cells) and has a strong projection to the dorsal thalamus and to the cerebral neocortex. By adulthood, the nucleus has much reduced in size and only a few cells remain. It is not clear whether these perireticular cells that remain into adulthood maintain their connections with the dorsal thalamus and with the neocortex. This study examines this issue by injecting neuronal tracers into various nuclei of the dorsal thalamus (dorsal lateral geniculate nucleus, medial geniculate complex, ventroposteromedial nucleus, lateral posterior nucleus, posterior thalamic nucleus) and into different areas of the neocortex (somatosensory, visual, auditory). After injections of tracer into the individual nuclei of the rat and ferret dorsal thalamus, retrogradely-labelled perireticular cells are seen. In general, after each injection, the retrogradely-labelled perireticular cells lie immediately adjacent to a group of retrogradely-labelled reticular cells. For instance, after injections into the medial geniculate complex, perireticular cells adjacent to the auditory reticular sector are retrogradely-labelled, whilst after an injection into the dorsal lateral geniculate nucleus, retrogradely-labelled perireticular cells adjacent to the visual reticular sector are seen. By contrast, injections of tracer into various areas of the rat and ferret neocortex result in no retrogradely-labelled cells in the perireticular nucleus. Thus, unlike during perinatal development when perireticular cells project to both neocortex and dorsal thalamus, perireticular cells in the adult seem to project to the dorsal thalamus only: the perireticular projection to the neocortex appears to be entirely transient.

The distribution of body fat from childhood to adulthood in a longitudinal study population.

Body fat distribution, its continuity from childhood (4-6 years) to 30 years of age, and its link to that of parents is described in a longitudinal study population. A computer-assisted image analysis technique was used to measure body fat distribution (as measured by waist and hip diameters) from somatotype photographs. Pearson correlation coefficients were used to assess the association between the waist/hip diameter ratio (WHDR) and the body mass index (BMI) at all ages and between the WHDR of parents and offspring. Both Pearson correlation coefficients and the Foulkes-Davis tracking index were used to assess tracking of the WHDR from childhood to age 30 years. Stepwise regression analyses were performed to determine the predictability of the WHDR at age 30 years from WHDRs in childhood and adolescence. Among both sexes the WHDR decreased and BMIs increased with age from childhood to 18 years, then both increased from age 18 to 30 years. The correlation between the WHDR and BMI was significant only at 30 years for males (r = 0.37; p < 0.05) and during all stages of adolescence in females (p < 0.05). Age-to-age correlations were high for both sexes (p < 0.0001), and remained significant over a span of up to 25 years. Using the Foulkes-Davis tracking index, tracking from the year of peak height velocity to 30 years (a span of approximately 20 years) was strong for both sexes. Parent and child WHDRs were correlated and differed by sex. Father-son correlations were not significant in childhood, but reached significance in early adolescence (2 years before the year of peak velocity) and remained significant to 30 years (p < 0.05). Mother-daughter correlations were significant at all ages (p < 0.05). The level of the WHDR at the peak of the pubertal growth spurt (year of peak height velocity) predicted up to 58% of the variance in males and 51% of the variance in females of the WHDR at 30 years. We conclude that the adult WHDR (a proxy for the waist/hip ratio) becomes evident by the year of the pubertal growth spurt in height.

Body mass index from childhood to middle age: a 50-y follow-up.

The tracking of body mass index (BMI) over a 50-y period in a longitudinal study was examined by using both correlation coefficients and the Foulkes-Davis tracking index. Over the long term, BMIs before maturity were poor predictors of middle-aged BMI status in females but were good predictors in males. The correlation between females' BMI in childhood and their BMIs at two points during middle age (40 and 50 y) was zero; in males it was r = 0.36 and 0.41, respectively. Between-age correlations were high (P less than 0.0001) for both sexes, reflecting stability in BMI over the shorter term (less than or equal to 10 y). The tracking of BMI (with the Foulkes-Davis tracking index) from childhood to middle age was better for males than for females (P less than 0.1). Linear-regression analysis was also used to assess the predictability of relative body size in middle age from earlier measures; BMI in childhood accounted for 0% of the variance in females and 17% in males. We conclude that the prediction of ponderosity in middle age from BMIs early in life is more reliable for males than for females.

Long-term memory of body weight and past weight satisfaction: a longitudinal follow-up study.

Recalled body weight and self-reported current weight were validated in a longitudinal study population by comparing recalls at 50 y to actual measures taken at ages 18, 30, 40, and 50 y. Recalled body weights were also compared with reported desired weights at these same ages. Self-reported weights at 50 y were equally accurate for both males and females; the mean reporting underestimate was -1.98 kg for males and -1.86 kg for females. Males' self reports at age 50 y were influenced by years of education (P less than 0.005) and current body size (P less than 0.0001) whereas females' were not. Correlations between recall of past weights and measured weights ranged from r = 0.87 at 18 y to 0.95 at 40 y. Recalls of past body weight were not significantly influenced by the passage of time, the number of years of education, or the accuracy of current weight reports. Current body size (wt/ht2) was significantly associated with life-time weight dissatisfaction in both sexes (P less than 0.0005).

Accuracy of recall by middle-aged participants in a longitudinal study of their body size and indices of maturation earlier in life.

The validity of long-term recall and current assessments of height, weight, and fatness relative to peers was investigated among 91 middle-aged participants in a longitudinal growth study. The recollections of 50-year-old participants concerning perceived body size in comparison to peers during childhood (aged 5-7 years), adolescence (aged 10-18 years), and at ages 30, and 40 years were compared with physical measurements taken at these times. Correlations between perceived and actual body size at all ages from childhood through middle-age were moderate but significant (P less than 0.005) and were influenced by gender and phases of physical growth (early and late adolescence). In general, accuracy of self-reports of current body size were not significantly better than recalls of body size up to 50 years earlier. Respondents' recall of various physiological events was also assessed. Females' actual and recalled year of menarche were correlated (r = 0.67; P less than 0.0001). Age at menarche was recalled within 1 year of the actual event by 84% of the females. Fifty percent of both sexes recalled their year of maximal growth in height within 1 year and recalled the timing of their maturation (early, average, or late) in relationship to their peers equally well (P less than 0.001).

Changes in relative weight among institutionalized elderly adults.

Weight-for-height and weight changes over a 2-year period among 335 institutionalized elderly adults at a geriatric care facility are described. Weight-for-height at admission was compared with several current standards for elderly persons. Mean relative weight and proportions of underweight and obese patients varied with the standards used. Although changes in group mean weights were slight, 73% of the patients gained or lost 4.5 kg or more in 2 years. Patients who lost 4.5 kg or more in the interval had a lower 4-year survival rate (p less than .05) than patients who gained weight or remained stable. Fluctuations in weight may be more prevalent among institutionalized elderly persons than previously thought, or than are apparent in analyses of group trends. Monitoring an individual's weight is simple and may be more meaningful than comparison to a standard, especially because weight loss is associated with mortality, until age appropriate standards are developed.