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881.
Patrick Tan 《BMC medicine》2008,6(1):27
Identifying the complete repertoire of genes and genetic variants that regulate the pathogenesis and progression of human
disease is a central goal of post-genomic biomedical research. In cancer, recent studies have shown that genome-wide association
studies can be successfully used to identify germline polymorphisms associated with an individual's susceptibility to malignancy.
In parallel to these reports, substantial work has also shown that patterns of somatic alterations in human tumors can be
successfully employed to predict disease prognosis and treatment response. A paper by Van Ness et al. published this month
in BMC Medicine reports the initial results of a multi-institutional consortium for multiple myeloma designed to evaluate the role of germline
polymorphisms in influencing multiple myeloma clinical outcome. Applying a custom-designed single nucleotide polymorphism
microarray to two separate patient cohorts, the investigators successfully identified specific combinations of germline polymorphisms
significantly associated with early clinical relapse. These results raise the exciting possibility that besides somatically
acquired alterations, germline genetic background may also exert an important influence on cancer patient prognosis and outcome.
Future 'personalized medicine' strategies for cancer may thus require incorporating genomic information from both tumor cells
and the non-malignant patient genome. 相似文献
882.
We have known for some time that the epidemiology of human stroke is sexually dimorphic until late in life, well beyond the
years of reproductive senescence and menopause. Now, a new concept is emerging: the mechanisms and outcome of cerebral ischemic injury are influenced strongly by biological sex as well as the availability of sex steroids to the
brain. The principal mammalian estrogen (17 β estradiol or E2) is neuroprotective in many types of brain injury and has been
the major focus of investigation over the past several decades. However, it is becoming increasingly clear that although hormones
are a major contributor to sex-specific outcomes, they do not fully account for sex-specific responses to cerebral ischemia.
The purpose of this review is to highlight recent studies in cell culture and animal models that suggest that genetic sex
determines experimental stroke outcome and that divergent cell death pathways are activated after an ischemic insult. These
sex differences need to be identified if we are to develop efficacious neuroprotective agents for use in stroke patients. 相似文献
883.
884.
Anthony J McGoron Michael Capille Michael F Georgiou Pablo Sanchez Juan Solano Manuel Gonzalez-Brito John W Kuluz 《BMC medical imaging》2008,8(1):4
Background
Assessment of cerebral blood flow (CBF) by SPECT could be important in the management of patients with severe traumatic brain injury (TBI) because changes in regional CBF can affect outcome by promoting edema formation and intracranial pressure elevation (with cerebral hyperemia), or by causing secondary ischemic injury including post-traumatic stroke. The purpose of this study was to establish an improved method for evaluating regional CBF changes after TBI in piglets. 相似文献885.
Biomechanical Properties of Esophagus during Systemic Treatment with Epidermal Growth Factor in Rats
Zhao J Yang J Vinter-Jensen L Zhuang F Gregersen H 《Annals of biomedical engineering》2003,31(6):700-709
The epidermal growth factor (EGF) is a growth factor with effects on many cell types and tissue. Morphometric and passive biomechanical properties were studied in isolated segments of the esophagus in 22 EGF-treated rats and 12 control rats. The rats were divided into groups with EGF treatment for 2, 4, 7, and 14 days (n=6 for each group except n=4 for the 14 days EGF-treatment group) or saline treatment (n=3 for each group). The mechanical test was performed as a distension experiment in vitro where the whole esophagus was stretched to its in situ length and distended with pressures up to 10 cm H2O using a ramp distension protocol. The pressure and outer diameter were recorded. Circumferential stress (force per area) and strain (deformation) were computed from the diameter and pressure data using the zero-stress state as reference. The zero-stress state was obtained by cutting esophageal rings radially. This caused the rings to open up into a sector. EGF induced pronounced morphometric changes, e.g., the wall thickness, wall cross-sectional area, and inner and outer circumferential lengths significantly increased during the EGF treatment. Histological analysis showed mucosa and submucosa growth during EGF treatment. The opening angle and residual strains increased with the highest value in the 14 days EGF-treated group (P < 0.05). The change in opening angle depended largely on the change in mucosa thickness. Furthermore, the circumferential stiffness of the esophagus reached a maximum after 7 days EGF treatment (P < 0.01). © 2003 Biomedical Engineering Society.
PAC2003: 8719Rr, 8717Ee 相似文献
886.
Rivka Levy Bernard Czernobilsky Benjamin Geiger 《Virchows Archiv : an international journal of pathology》1991,418(5):447-455
Summary The aim of the present study was to explore the origin of cloacogenic carcinoma in the anal canal by immunohistochemical methods. We compared cytokeratin polypeptide expression of a cloacogenic carcinoma to normal anal epithelia, to anal squamous cell carcinoma and to basal and squamous cell carcinoma of the skin, using a battery of monoclonal anti-cytokeratin, polypeptide-specific antibodies. Our results indicate that cloacogenic carcinoma expresses cytokeratin polypeptides similar to those of the basal layer of anal squamous epithelium, of the anal transitional zone epithelium and of a layer of basal cells in the anal glands. Thus we concluded that each of the above cell types may be the cell of origin of cloacogenic carcinoma. 相似文献
887.
Bruce R. Whiting Timothy A. Holden Barry S. Brunsden Charles C. Finley Margaret W. Skinner 《Journal of digital imaging》2008,21(3):323-328
While 3-dimensional (3D) imaging by computed tomography has long been desirable for research and treatment of cochlear-implant
patients, technical challenges have limited its wide application. Recent developments in scanner hardware and image processing
techniques now allow image quality improvements that make clinical applications feasible. Validation experiments were performed
to characterize a new methodology and its imaging performance. 相似文献
888.
It has become clear in recent years that programmed cell death occurs spontaneously in the cycle of the seminiferous epithelium. Induced germ cell apoptosis occurs at specific stages of the spermatogenic cycle and the existence of supracellular control of germ cell death during spermatogenesis has been documented. If apoptosis is a key phenomenon in the control of sperm production, the existence and role of apoptosis in ejaculated sperm cells remain controversial. Apoptosis - as determined by DNA fragmentation (Tunel) and ultrastructural analysis - is abnormally frequent in the sperm cells of the ejaculate of sterile men. In this review, we discuss the possible origins of DNA damage in ejaculated human spermatozoa and the consequences of these DNA damage if the apoptotic spermatozoa is used for ICSI. Percentages of DNA fragmentation in human ejaculated sperm correlated with fertilization rates after FIV or ICSI assay. Detection of DNA fragmentation in human sperm could provide additional information about the biochemical integrity of sperm and may be used in future studies for fertilization failures not explained by conventional sperm parameters. However, the analysis of other molecular markers of apoptosis (Fas, Annexine V.) is now necessary to assess the role of apoptosis in human ejaculated sperm cells. 相似文献
889.
890.