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101.
Bigio IJ Bown SG Briggs G Kelley C Lakhani S Pickard D Ripley PM Rose IG Saunders C 《Journal of biomedical optics》2000,5(2):221-228
We report on the first stages of a clinical study designed to test elastic-scattering spectroscopy, mediated by fiberoptic probes, for three specific clinical applications in breast-tissue diagnosis: (1) a transdermal-needle (interstitial) measurement for instant diagnosis with minimal invasiveness similar to fine-needle aspiration but with sensitivity to a larger tissue volume, (2) a hand-held diagnostic probe for use in assessing tumor/resection margins during open surgery, and (3) use of the same probe for real-time assessment of the "sentinel" node during surgery to determine the presence or absence of tumor (metastatic). Preliminary results from in vivo measurements on 31 women are encouraging. Optical spectra were measured on 72 histology sites in breast tissue, and 54 histology sites in sentinel nodes. Two different artificial intelligence methods of spectral classification were studied. Artificial neural networks yielded sensitivities of 69% and 58%, and specificities of 85% and 93%, for breast tissue and sentinel nodes, respectively. Hierarchical cluster analysis yielded sensitivities of 67% and 91%, and specificities of 79% and 77%, for breast tissue and sentinel nodes, respectively. These values are expected to improve as the data sets continue to grow and more sophisticated data preprocessing is employed. The study will enroll up to 400 patients over the next two years. 相似文献
102.
Epitopes with linear sequences recognized by anti-La autoantibodies from seven mothers of children with congenital heart block were recently defined. Eight of these epitopes share sequence identity with three other proteins in addition to the original autoantigen, La. The three proteins are human cardiac myosin beta heavy chain, laminin B1 chain and the M6 protein of Streptococcus pyogenes. Affinity purified anti-La antibodies from a further three mothers bound to the La antigen and also to human cardiac myosin and mouse laminin. Affinity purified antibodies from three mothers of healthy children bound to the La antigen but showed minimal binding to either human cardiac myosin or mouse laminin. Cardiac myosin inhibited the binding of CHB-related anti-La antibodies to both La and myosin. These data support a role for maternal autoantibodies crossing the placenta and recognizing foetal cardiac antigens accessible at a critical developmental stage during gestation. We suggest that this would lead to complement fixation, inflammation and the subsequent pathology associated with congenital heart block. 相似文献
103.
Avian cryptococcosis. 总被引:2,自引:0,他引:2
R Malik M B Krockenberger G Cross R Doneley D N Madill D Black P McWhirter A Rozenwax K Rose M Alley D Forshaw I Russell-Brown A C Johnstone P Martin C R O'Brien D N Love 《Medical mycology》2003,41(2):115-124
Clinical and laboratory findings in 15 unreported cases of avian cryptococcosis from Australia were collated and contrasted with 11 cases recorded in the literature. Cryptococcus species produced localized invasive disease of the upper respiratory tract of captive parrots living in Australia. This resulted in signs referable to mycotic rhinitis or to involvement of structures contiguous with the nasal cavity, such as the beak, sinuses, choana, retrobulbar space and palate. Parrots of widely differing ages were affected and of the seven birds for which sex was determinable, six were male. Cryptococcus bacillisporus (formerly C. neoformans var. gattii) accounted for four of five infections in which the species or variety was determinable, suggesting that exposure to eucalyptus material may be a predisposing factor. In these cases, Cryptococcus appeared to behave as a primary pathogen of immunocompetent hosts. One tissue specimen was available from an Australian racing pigeon with minimally invasive subcutaneous disease; immunohistology demonstrated a C. neoformans var. grubii (formerly C. neoformans var. neoformans serotype A) infection, presumably subsequent to traumatic inoculation of yeast cells into the subcutis. Two similar cases had been reported previously in pigeons domiciled in America. Data for parrots, one pigeon and other birds studied principally in America and Europe (and likely infected with C. neoformans) suggested a different pattern of disease, more suggestive of opportunistic infection of immunodeficient hosts. In this cohort of patients, the organism was not restricted to cool superficial sites such as the upper respiratory tract or subcutis. Instead, infections typically penetrated the lower respiratory tract or disseminated widely to a variety of internal organs. Finally, three captive North Island brown kiwis, one residing in Australia, the other two in New Zealand, died as a result of severe diffuse cryptococcal pneumonia (two cases) or widely disseminated disease (one case). C. bacillisporus strains were isolated from all three cases, as reported previously for another kiwi with disseminated disease in New Zealand. 相似文献
104.
Edmonston TB Cuesta KH Burkholder S Barusevicius A Rose D Kovatich AJ Boman B Fry R Fishel R Palazzo JP 《Human pathology》2000,31(12):1506-1514
Molecular analysis of hereditary nonpolyposis colorectal carcinomas (HNPCC) has identified DNA mismatch repair deficiencies with resulting microsatellite instability (MSI) as a pathway of carcinogenesis that appears to be relevant for prognosis, treatment, and possibly prevention. In this study, expression of cell cycle proteins and other known prognostic markers is correlated with the microsatellite status of colorectal cancers (CRC). One hundred consecutive cases from the CRC Registry at Thomas Jefferson University were analyzed for MSI. Immunohistochemistry was performed for the mismatch repair proteins hMLH1 and hMSH2, tumor suppressor p53, apoptosis inhibitor bcl-2, cell cycle proteins p21(WAF1/CIP1), and p27 and the proliferation markers Ki-67 and topoisomerase II. High MSI (MSI-H) is significantly correlated with loss of either hMLH1 or hMSH2, presence of bcl-2, and absence of p53. p21(WAF1/CIP1) is positive in all tumors with MSI-H. Previous findings of a lower proliferation rate were confirmed with a topoisomerase II stain. Microsatellite stable (MSS) tumors generally express both MSH2 and MLH1. Other highly significant differences are positive p53 in 56% of MSS cases and negative bcl-2 in 98% of MSS cases. p27 expression is found in approximately 50% of all CRCs irrespective of the microsatellite status. MSI-H tumors follow the mutator pathway, with loss of expression of one mismatch repair protein, wild-type p53, lower proliferation, and positivity for p21(WAF1/CIP1). MSS tumors follow the suppressor pathway, characterized by p53 overexpression, higher proliferation, and absence of bcl-2 expression; p21(WAF1/CIP1) expression can be variable. These data provide a molecular basis for the clinical observation that patients with HNPCC appear to have a more favorable prognosis. HUM PATHOL 31:1506-1514. 相似文献
105.
B B Rasmussen C Rose S M Thorpe K W Andersen K Hou-Jensen 《American journal of clinical pathology》1985,84(6):737-740
Two hundred two human, mucinous breast carcinomas were investigated for the presence of argyrophilic granules, and these granules were found in 25% of the cases. The granules were located in the cytoplasm and were heterogeneously distributed within the tumors. Tumors with granules were otherwise morphologically indistinguishable from those tumors without granules. The recurrence-free survival was independent of the presence of granules, and no relation was found to other clinical or histopathologic factors. Tumors with granules were found to be estrogen-receptor positive, and they appear to have a slightly less aggressive growth pattern than tumors without granules, but the difference is far from being statistically significant. It is concluded that there is no convincing evidence that this group of primary breast carcinomas with argyrophilia originates from APUD cells. 相似文献
106.
Factors altering the sleep of burned children 总被引:4,自引:0,他引:4
Although few studies have been conducted on burn patients, they indicate that sleep of burned children is altered. We suggest in this review, on the basis of the limited data available that factors contributing to sleep disruption in burned individuals may be broadly categorized as pathophysiological responses to the injury, the pain and discomfort experienced by the patient and medications used to treat these symptoms, and the physical environment in the Burns Intensive Care Unit. The responses to thermal injury include alterations in circulating neuropeptides, hormones, and immune-active substances, many of which are known to regulate/modulate sleep. Medications for the management of pain and for treating symptoms of various injury-induced stress and anxiety disorders may also alter sleep. Finally, frequent disruptions of the patient by medical staff is but one of the many environmental factors that may contribute to disrupted sleep. Severe burns induce a hypermetabolic response that may result in peripheral wasting, that depletes substrates necessary for tissue repair, and is associated with reduced growth hormone. Burn-induced growth hormone insufficiency is aggressively treated to counteract peripheral wasting and to aid in wound healing of skin graft donor sites. We speculate that improvement of sleep quality would result in a less severe reduction in growth hormone due to the well documented relationship between slow-wave sleep onset and growth hormone secretion. Such improvement in spontaneous growth hormone secretion patterns may aid in recovery by supporting tissue repair and by minimizing the hypermetabolic response to thermal injury. The experiments to test such hypotheses remain to be conducted, yet the results of such experiments may provide the basis for beginning to answer the question of whether or not sleep aids in recovery from injury. 相似文献
107.
Hybrid cell lines producing monoclonal antibodies against human prostatic acid phosphatase (E. C. 3.1.3.2) were prepared by the fusion of mouse myeloma cells with the spleen cells of BALB/c mice and Lewis rats immunized with prostatic acid phosphatase (PAP). Approximately 14% of the hybrid cell microcultures which produced specific antibodies were cloned, and 6 eventually yielded stable cell lines. The monoclonal antibodies produced by these 6 hybridomas were characterized for their isotypes, isoelectric points, concentrations and affinities. The specificity of these monoclonal antibodies was further investigated by radioimmunoassay and immunohistochemical methods. All of the 6 monoclonal antibodies exhibited strict specificity for prostatic acid phosphatase. 相似文献
108.
Cholecystokinin octapeptide and the C-terminal tetrapeptide are hydrolysed by a highly purified preparation of "enkephalinase" (EC 3.4.24.11). In both cases the Asp-PheNH2 bond is hydrolysed and the Gly4-Trp5 bond of the octapeptide is also cleaved, though more slowly. Evaluated from the appearance of Phe-NH2, the Km for the hydrolysis of the octapeptide by the purified peptidase is 57 microM and that for the tetrapeptide 65 microM. The apparent affinities of these peptides for the enzyme in striatal membranes are similar. The importance of this hydrolysis in the inactivation of endogenous cholecystokinin was assessed by studying the fate of cholecystokinin immunoreactivity released from slices of rat cerebral cortex and striatum by depolarization with potassium. In the absence of any peptidase inhibitor only 16% of the peptide released from the tissue was recovered in immunoreactive form in the medium, indicating that endogenous cholecystokinin octapeptide is, like other neuropeptides, rapidly and extensively hydrolysed following release. Selective inhibition of "enkephalinase" by Thiorphan (DL-3-mercapto-2-benzylpropanoyl glycine) did not significantly alter the recovery from slices of cerebral cortex and had only a very slight effect in the case of striatal slices. This suggests that, while cholecystokinin octapeptide is a substrate for "enkephalinase", this enzyme plays a less important (if any) role in the inactivation of endogenous cholecystokinin than for the opioid peptides. 相似文献
109.
110.
Species-specific tissue antigens. II. A human species-specific antigen possessing esterase activity 总被引:1,自引:2,他引:1
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W. R. Bartholomew Eleanor A. Bartholomew Georgirene D. Therrien N. R. Rose 《Clinical and experimental immunology》1972,12(1):153-159
An esterase that is limited in species distribution to human and monkey tissues was demonstrated by enzymoimmunoelectrophoresis and enzymoimmunodiffusion. The monkey esterase exhibited a slightly faster electrophoretic mobility than the human tissue esterase. An antigenically identical esterase found in concentrated human urine had a mobility slightly more anodal than the human tissue esterase. Despite the differences in electrophoretic mobility among the human tissue esterase, urinary esterase and monkey tissue esterase, they all reacted in enzymoimmunodiffusion with antiserum to cellular or urinary esterase to produce lines of immunologic identity. Tissues of the other species tested did not exhibit the human cathodal esterase. 相似文献