2,183 research outputs found
Clinicopathological features and the value of differential Cytokeratin 7 and 20 expression in resolving diagnostic dilemmas of ovarian involvement by colorectal adenocarcinoma and vice-versa
The distinction between metastasis from a colorectal adenocarcinoma into the ovary and an ovarian adenocarcinoma is vital, but challenging at times, due to overlapping morphological features. Similarly, a distinction between an ovarian metastasis into the colorectum and a colorectal adenocarcinoma, although rare; is important and can be daunting. We report an analysis of 20 cases of ovarian involvement by metastatic colorectal adenocarcinomas and colorectal involvement by metastatic ovarian adenocarcinomas, including the value of differential expression of cytokeratins 7 & 20 by immunohistochemistry (IHC), in these cases. Nine cases (45%) were identified as colorectal adenocarcinomas metastatic to the ovary. On biopsy, all these cases showed a 'garland-like' tumor necrosis, with desmoplasia and predominantly exhibited a tubuloalveolar pattern (67% cases). On IHC, all 8 of 9 such cases, where staining for cytokeratin 20 was performed, displayed strong positivity and 7 cases, where staining for carcinoembryogenic antigen (CEA) was performed, revealed positivity for this marker (100%). Other 11 cases (55%) were ovarian adenocarcinomas, metastatic to the colorectum. These showed metachronous presentations, with the ovarian tumor preceding the colorectal tumor deposits. Morphologically, psammomatous calcification was noted in 73% of these cases, whereas 'garland-like' necrosis was absent in all. The chief morphological subtype was serous papillary cystadenocarcinoma (55% cases). On IHC, CK7 and CA 125 were positive in all 6 of 11 such cases, whereas CK 20 was negative in all these cases
Isolation, purification, and full NMR assignments of cyclopamine from Veratrum californicum
The Hedgehog signaling pathway is essential for embryogenesis and for tissue homeostasis in the adult. However, it may induce malignancies in a number of tissues when constitutively activated, and it may also have a role in other forms of normal and maladaptive growth. Cyclopamine, a naturally occurring steroidal alkaloid, specifically inhibits the Hedgehog pathway by binding directly to Smoothened, an important Hedgehog response element. To use cyclopamine as a tool to explore and/or inhibit the Hedgehog pathway in vivo, a substantial quantity is required, and as a practical matter cyclopamine has been effectively unavailable for usage in animals larger than mice
The epidemiology of injuries across the weight-training sports
Background: Weight-training sports, including weightlifting, powerlifting, bodybuilding, strongman, Highland Games, and CrossFit, are weight-training sports that have separate divisions for males and females of a variety of ages, competitive standards, and bodyweight classes. These sports may be considered dangerous because of the heavy loads commonly used in training and competition. Objectives: Our objective was to systematically review the injury epidemiology of these weight-training sports, and, where possible, gain some insight into whether this may be affected by age, sex, competitive standard, and bodyweight class. Methods: We performed an electronic search using PubMed, SPORTDiscus, CINAHL, and Embase for injury epidemiology studies involving competitive athletes in these weight-training sports. Eligible studies included peer-reviewed journal articles only, with no limit placed on date or language of publication. We assessed the risk of bias in all studies using an adaption of the musculoskeletal injury review method. Results: Only five of the 20 eligible studies had a risk of bias score β₯75 %, meaning the risk of bias in these five studies was considered low. While 14 of the studies had sample sizes >100 participants, only four studies utilized a prospective design. Bodybuilding had the lowest injury rates (0.12β0.7 injuries per lifter per year; 0.24β1 injury per 1000 h), with strongman (4.5β6.1 injuries per 1000 h) and Highland Games (7.5 injuries per 1000 h) reporting the highest rates. The shoulder, lower back, knee, elbow, and wrist/hand were generally the most commonly injured anatomical locations; strains, tendinitis, and sprains were the most common injury type. Very few significant differences in any of the injury outcomes were observed as a function of age, sex, competitive standard, or bodyweight class. Conclusion: While the majority of the research we reviewed utilized retrospective designs, the weight-training sports appear to have relatively low rates of injury compared with common team sports. Future weight-training sport injury epidemiology research needs to be improved, particularly in terms of the use of prospective designs, diagnosis of injury, and changes in risk exposure
Comparison of Hospital Costs and Length of Stay for Community Internists, Hospitalists, and Academicians
BACKGROUND: The model of inpatient medical management has evolved toward Hospitalists because of greater cost efficiency compared to traditional practice. The optimal model of inpatient care is not known. OBJECTIVE: To compare three models of inpatient Internal Medicine (traditional private practice Internists, private Hospitalist Internists, and Academic Internists with resident teams) for cost efficiency and quality at a community teaching hospital. DESIGN: Single-institution retrospective cohort study. MEASUREMENTS AND MAIN RESULTS: Measurements were hospital cost, length of stay (LOS), mortality, and 30-day readmission rate adjusted for severity, demographics, and case mix. Academic Internist teams had 30% lower cost and 40% lower LOS compared to traditional private Internists and 24% lower cost and 30% lower LOS compared to private Hospitalists. Hospital mortality was equivalent for all groups. Academic teams had 2.3β2.6% more 30-day readmissions than the other groups. CONCLUSIONS: Academic teams compare favorably to private Hospitalists and traditional Internists for hospital cost efficiency and quality
Distribution of raphespinal fibers in the mouse spinal cord
Background: Serotonergic raphespinal neurons and their fibers have been mapped in large mammals, but the non- serotonergic ones have not been studied, especially in the mouse. The present study aimed to investigate the termination pattern of fibers arising from the hindbrain raphe and reticular nuclei which also have serotonergic neurons by injecting the anterograde tracer BDA into them. Results: We found that raphespinal fibers terminate in both the dorsal and ventral horns in addition to lamina 10. There is a shift of the fibers in the ventral horn towards the dorsal and lateral part of the gray matter. Considerable variation in the termination pattern also exists between raphe nuclei with raphe magnus having more fibers terminating in the dorsal horn. Fibers from the adjacent gigantocellular reticular nucleus show similar termination pattern as those from the raphe nuclei with slight difference. Immunofluorescence staining showed that raphespinal fibers were heterogeneous and serotoninergic fibers were present in all laminae but mainly in laminae 1, 2, medial lamina 8, laminae 9 and 10. Surprisingly, immunofluorescence staining on clarified spinal cord tissue revealed that serotoninergic fibers formed bundles regularly in a short distance along the rostrocaudal axis in the medial part of the ventral horn and they extended towards the lateral motor neuron column area. Conclusion: Serotonergic and non-serotonergic fibers arising from the hindbrain raphe and reticular nuclei had similar termination pattern in the mouse spinal cord with subtle difference. The present study provides anatomical foundation for the multiple roles raphe and adjacent reticular nuclei play
Cardiovascular disease in a cohort exposed to the 1940-45 Channel Islands occupation
BACKGROUND
To clarify the nature of the relationship between food deprivation/undernutrition during pre- and postnatal development and cardiovascular disease (CVD) in later life, this study examined the relationship between birth weight (as a marker of prenatal nutrition) and the incidence of hospital admissions for CVD from 1997β2005 amongst 873 Guernsey islanders (born in 1923β1937), 225 of whom had been exposed to food deprivation as children, adolescents or young adults (i.e. postnatal undernutrition) during the 1940β45 German occupation of the Channel Islands, and 648 of whom had left or been evacuated from the islands before the occupation began.
METHODS
Three sets of Cox regression models were used to investigate (A) the relationship between birth weight and CVD, (B) the relationship between postnatal exposure to the occupation and CVD and (C) any interaction between birth weight, postnatal exposure to the occupation and CVD. These models also tested for any interactions between birth weight and sex, and postnatal exposure to the occupation and parish of residence at birth (as a marker of parish residence during the occupation and related variation in the severity of food deprivation).
RESULTS
The first set of models (A) found no relationship between birth weight and CVD even after adjustment for potential confounders (hazard ratio (HR) per kg increase in birth weight: 1.12; 95% confidence intervals (CI): 0.70 β 1.78), and there was no significant interaction between birth weight and sex (p = 0.60). The second set of models (B) found a significant relationship between postnatal exposure to the occupation and CVD after adjustment for potential confounders (HR for exposed vs. unexposed group: 2.52; 95% CI: 1.54 β 4.13), as well as a significant interaction between postnatal exposure to the occupation and parish of residence at birth (p = 0.01), such that those born in urban parishes (where food deprivation was worst) had a greater HR for CVD than those born in rural parishes. The third model (C) found no interaction between birth weight and exposure to the occupation (p = 0.43).
CONCLUSION
These findings suggest that the levels of postnatal undernutrition experienced by children, adolescents and young adults exposed to food deprivation during the 1940β45 occupation of the Channel Islands were a more important determinant of CVD in later life than the levels of prenatal undernutrition experienced in utero prior to the occupatio
P2Y Receptors Sensitize Mouse and Human Colonic Nociceptors.
Activation of visceral nociceptors by inflammatory mediators contributes to visceral hypersensitivity and abdominal pain associated with many gastrointestinal disorders. Purine and pyrimidine nucleotides (e.g., ATP and UTP) are strongly implicated in this process following their release from epithelial cells during mechanical stimulation of the gut, and from immune cells during inflammation. Actions of ATP are mediated through both ionotropic P2X receptors and metabotropic P2Y receptors. P2X receptor activation causes excitation of visceral afferents; however, the impact of P2Y receptor activation on visceral afferents innervating the gut is unclear. Here we investigate the effects of stimulating P2Y receptors in isolated mouse colonic sensory neurons, and visceral nociceptor fibers in mouse and human nerve-gut preparations. Additionally, we investigate the role of Nav1.9 in mediating murine responses. The application of UTP (P2Y2 and P2Y4 agonist) sensitized colonic sensory neurons by increasing action potential firing to current injection and depolarizing the membrane potential. The application of ADP (P2Y1, P2Y12, and P2Y13 agonist) also increased action potential firing, an effect blocked by the selective P2Y1 receptor antagonist MRS2500. UTP or ADP stimulated afferents, including mouse and human visceral nociceptors, in nerve-gut preparations. P2Y1 and P2Y2 transcripts were detected in 80% and 56% of retrogradely labeled colonic neurons, respectively. Nav1.9 transcripts colocalized in 86% of P2Y1-positive and 100% of P2Y2-positive colonic neurons, consistent with reduced afferent fiber responses to UTP and ADP in Na(v)1.9(-/-) mice. These data demonstrate that P2Y receptor activation stimulates mouse and human visceral nociceptors, highlighting P2Y-dependent mechanisms in the generation of visceral pain during gastrointestinal disease.This work was supported by The Medical Research Council (D.C.B.), a Wellcome Trust University Award (L.A.B.), Neusentis (D.C.B.), The Royal College of Surgeons of England (G.B.), The Biotechnology and Biological Sciences Research Council (J.R.F.H.), Bowel & Cancer Research (M.A.T.), Pain Relief Foundation and Crohn's in Childhood Research Association (V.C.-G.), and The Dr Hadwen Trust for Humane Research (C.M.)
Vehicle emissions and consumer information in car advertisements
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Ex vivo study of human visceral nociceptors.
OBJECTIVE: The development of effective visceral analgesics free of deleterious gut-specific side effects is a priority. We aimed to develop a reproducible methodology to study visceral nociception in human tissue that could aid future target identification and drug evaluation. DESIGN: Electrophysiological (single unit) responses of visceral afferents to mechanical (von Frey hair (VFH) and stretch) and chemical (bradykinin and ATP) stimuli were examined. Thus, serosal afferents (putative nociceptors) were used to investigate the effect of tegaserod, and transient receptor potential channel, vanilloid 4 (TRPV4) modulation on mechanical responses. RESULTS: Two distinct afferent fibre populations, serosal (n=23) and muscular (n=21), were distinguished based on their differences in sensitivity to VFH probing and tissue stretch. Serosal units displayed sensitivity to key algesic mediators, bradykinin (6/14 units tested) and ATP (4/10), consistent with a role as polymodal nociceptors, while muscular afferents are largely insensitive to bradykinin (0/11) and ATP (1/10). Serosal nociceptor mechanosensitivity was attenuated by tegaserod (-20.8Β±6.9%, n=6, p<0.05), a treatment for IBS, or application of HC067047 (-34.9Β±10.0%, n=7, p<0.05), a TRPV4 antagonist, highlighting the utility of the preparation to examine the mechanistic action of existing drugs or novel analgesics. Repeated application of bradykinin or ATP produced consistent afferent responses following desensitisation to the first application, demonstrating their utility as test stimuli to evaluate analgesic activity. CONCLUSIONS: Functionally distinct subpopulations of human visceral afferents can be demonstrated and could provide a platform technology to further study nociception in human tissue
Alpha-particle-induced complex chromosome exchanges transmitted through extra-thymic lymphopoiesis in vitro show evidence of emerging genomic instability
Human exposure to high-linear energy transfer Ξ±-particles includes environmental (e.g. radon gas and its decay progeny), medical (e.g. radiopharmaceuticals) and occupational (nuclear industry) sources. The associated health risks of Ξ±-particle exposure for lung cancer are well documented however the risk estimates for leukaemia remain uncertain. To further our understanding of Ξ±-particle effects in target cells for leukaemogenesis and also to seek general markers of individual exposure to Ξ±-particles, this study assessed the transmission of chromosomal damage initially-induced in human haemopoietic stem and progenitor cells after exposure to high-LET Ξ±-particles. Cells surviving exposure were differentiated into mature T-cells by extra-thymic T-cell differentiation in vitro. Multiplex fluorescence in situ hybridisation (M-FISH) analysis of naΓ―ve T-cell populations showed the occurrence of stable (clonal) complex chromosome aberrations consistent with those that are characteristically induced in spherical cells by the traversal of a single Ξ±-particle track. Additionally, complex chromosome exchanges were observed in the progeny of irradiated mature T-cell populations. In addition to this, newly arising de novo chromosome aberrations were detected in cells which possessed clonal markers of Ξ±-particle exposure and also in cells which did not show any evidence of previous exposure, suggesting ongoing genomic instability in these populations. Our findings support the usefulness and reliability of employing complex chromosome exchanges as indicators of past or ongoing exposure to high-LET radiation and demonstrate the potential applicability to evaluate health risks associated with Ξ±-particle exposure.This work was supported by the Department of Health, UK. Contract RRX95 (RMA NSDTG)
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