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71.
Dpc4 is expressed in virtually all primary and metastatic pancreatic endocrine carcinomas 总被引:2,自引:0,他引:2
Scarpa A Orlandini S Moore PS Lemoine NR Beghelli S Baron A Falconi M Zamboni G 《Virchows Archiv : an international journal of pathology》2002,440(2):155-159
DPC4/Smad4 is inactivated in about 50% of pancreatic ductal cancers. It has been recently reported that this gene is also inactivated in neoplasms arising from pancreatic islet cells, a phenomenon suggested to be related to similar progressions of malignancy found in common ductal cancers. To evaluate this possibility, we analysed 20 metastases of pancreatic endocrine carcinomas and their corresponding primary lesion for inactivation of DPC4 using immunohistochemical staining. In fact, immunohistochemical labelling has been shown to correlate with DPC4 gene status with high sensitivity and specificity. The cancers included 18 nonfunctioning tumours, one gastrinoma and one ViPoma all with liver, nodal and/or adrenal metastases. Seventeen were well-differentiated and three poorly differentiated endocrine carcinomas. Dpc4 expression was absent in only one primary well-differentiated endocrine cancer and its liver metastasis, while all the remaining 19 primary tumours and their metastases stained positive for the protein. All positively staining cases showed diffuse cytoplasmic and nuclear staining in virtually all neoplastic cells. Our data suggest that DPC4 is only rarely involved in pancreatic endocrine tumourigenesis and give further weight to the hypothesis that tumours arising from pancreatic exocrine and endocrine epithelia are genetically distinct. 相似文献
72.
Bovine spongiform encephalopathy 总被引:1,自引:0,他引:1
The identification of variant Creutzfeldt-Jakob disease (vCJD) in human strongly reinforced the perception of risks associated with the infectious agent involved in Bovine Spongiform Encephalopathy (BSE). The development of rapid tests for the diagnosis of BSE by the detection of the abnormal prion protein allowed a huge increase in surveillance of the cattle disease. This first revealed a higher prevalence of the infection than previously believed. However, food safety measures, mainly based on the ban of the use of meat and bone meal in ruminants and the elimination of specified risk materials from the food chain, already allowed significant progress in the control of the cattle disease, especially in the United Kingdom. Nevertheless, the diagnosis can still not be obtained in the live animal, while the disease only appears following a several years incubation period. Another major issue is the identification of the BSE agent when it has been transmitted to another species. This question not only arises in veterinary medicine, with the major question of a possible infection of small ruminants by the BSE agent, but also in human in which the existence of other forms of the disease linked to the BSE agent but possibly differing from Creutzfeldt-Jakob disease cannot be excluded. 相似文献
73.
Imatinib mesylate (tested as STI571), an abl kinase inhibitor, induces sustained, complete hematologic and cytogenetic responses in chronic myelocytic leukemia (CML) patients; however, emergence of clonal chromosomal aberrations in Philadelphia-negative (Ph-) cells during treatment has been reported. We describe two CML patients in chronic phase who presented with complete cytogenetic responses during imatinib mesylate therapy but developed new clonal chromosomal rearrangements in Ph- cells. The first patient presented with a duplication of chromosome 1, dup(1)(q21q42), and the second showed two new clonal aberrations consisting of inv(1)(q12q32) and del(7)(q22) in the same clone. 相似文献
74.
Meltem Yüksel Elma Baron Melissa Camouse Brenda W Cooper Hillard M Lazarus Stanton L Gerson Mary J Laughlin Kevin D Cooper Anita Gilliam Pingfu Fu Seth Stevens Omer N Ko? 《Biology of blood and marrow transplantation》2006,12(6):665-671
Whole-body UV-B phototherapy has been used for the treatment of graft-versus-host disease (GVHD) of the skin and has systemic immunosuppressive and tolerogenic effects. We hypothesized that whole-body UV-B therapy would improve donor engraftment and decrease the incidence and severity of GVHD that is associated with decreased intensity allogeneic hematopoietic stem cell transplantation. This study tested the feasibility of using UV-B phototherapy that was initiated before grafting and continued until engraftment to determine its effect on transplantation outcome. Eight patients (median age, 55.5 years; range, 32-65 years) with hematologic malignancies were included. Allogeneic peripheral blood stem cells were obtained from matched related (n=5) or matched unrelated (n=3) donors. Conditioning regimen was fludarabine 30 mg/m2 intravenously for 5 days, cyclophosphamide 1 g/m2/d intravenously for 2 days, and equine antithymocyte globulin 30 mg/kg/d for 2 days. GVHD prophylaxis included cyclosporine, methylprednisolone, and escalating doses of narrowband UV-B (311 nm) according to skin tolerance, 3 days a week, from 10 days before to 28 days after transplantation. The conditioning regimen and the UV-B therapy were well tolerated. Two patients received all 14 prescribed UV-B treatments (cumulative doses of 2000 and 3260 mJ/cm2, respectively) and 6 patients received 8 to 13 treatments with a cumulative dose range of 528-3465 mJ/cm2. There was a rapid decrease in epidermal CD1a+ cells by day of transplantation. Myeloid engraftment was rapid. One patient had secondary engraftment failure at 3 months and another had mixed chimerism at day 100. Seven of 8 patients developed severe acute GVHD (grade III, n=5; grade IV, n=2). Six had skin involvement, 5 had gastrointestinal involvement, and 1 had liver involvement. Four patients died (2 from sepsis, 1 from acute GVHD, and 1 from chronic GVHD). Four patients are alive (130-287 days), 3 with extensive chronic GVHD. We conclude that extended peritransplant UV-B therapy at the standard minimally erythemogenic dose is detrimental to the outcome of allogeneic stem cell transplantation. It is unclear how UV-B at this immunsuppressive dose might have altered skin and systemic cytokine and immune cell compositions in the host and increased GVHD- and treatment-related mortalities. Different UV-B dose and schedules should be further explored. However, although other phototherapeutic modalities may be effective against GVHD, extended UV-B therapy should not be used during early phases of decreased conditioning allogeneic transplantation. 相似文献
75.
Le Caignec C Baron S McElreavey K Joubert M Rival JM Mechinaud F David A 《American journal of medical genetics. Part A》2003,(1):37-43
46,XY gonadal dysgenesis is characterized by abnormal testicular determination. We describe a large kindred in which various disorders of sexual development were observed, ranging from completely female phenotype without ambiguities of the external genitalia (five cases) to men with isolated penile or perineal hypospadias (four cases), including two cases with moderate virilization and one case with ambiguity of the external genitalia. Histologic examination of gonadal tissue was performed on seven subjects. These findings were suggestive of complete gonadal dysgenesis in one patient, partial gonadal dysgenesis in three patients, and mixed gonadal dysgenesis in three patients. Four patients developed gonadal tumors (two gonadoblastoma, two dysgerminoma, and one immature teratoma, i.e., one patient had a dysgerminoma with some areas of gonadoblastoma). All affected subjects had no other congenital anomalies or dysmorphic features. Analysis of families with several affected individuals with 46,XY gonadal dysgenesis implied an X-linked mode of inheritance because of the apparent absence of male-to-male transmission. However, a sex-limited autosomal dominant mode of inheritance affecting only XY individuals could not be ruled out. Analysis of the pedigree we report indicated an autosomal dominant mode of inheritance because of male-to-male transmission. This kindred supports the involvement of at least one autosomal gene in non-syndromic 46,XY gonadal dysgenesis. 相似文献
76.
M.-H. Lachapelle P. Miron R. Hemmings C. Baron D. C. Roy 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,35(1):5-13
Lachapelle M-H, Miron P, Hemmings R, Baron C, Roy DC. Flow-cytometric characterization of hematopoietic cells in non-pregnant human endometrium. Am J Reprod Immunol 1996; 35:5–13 cP Munksgaard, Copenhagen PROBLEM: Immunologic evaluation and quantitation of hematopoietic cells in human endometrium has been difficult to perform, particularly in nonpregnant subjects. In this study, we describe a method for the flow-cytometric characterization of hematopoietic cells present in the endometrium of non-pregnant women. METHOD: Endometrial biopsy samples from normal donors were first mechanically disrupted and filtered to generate a single-cell suspension of leukocyte-enriched endometrial cells. Cells were labeled with a panel of monoclonal antibodies, stained with propidium iodide (PI), and one- or two-color flow-cytometric analysis performed on cells excluding PI. RESULTS: The methodology described in this study was highly reproducible in experiments evaluating the interrun and intrarun variability. We then determined the immunophenotypic profile of endometrial leukocytes from 12 normal females. The majority of leukocytes were T cells (CD3: 47%; CD4: 24%; CD8: 28%) with an important contingent of NK cells (CD56: 32%), the majority of which harbored the unusual CD16-CD56 bright phenotype, and a minority of B cells (CD20: 6%) and monocytes (CD14: 7%). CONCLUSIONS: Flow cytometry can be used to assess antigen expression on the surface of endometrial leukocytes from nonpregnant women. In future studies, it will be possible to use this approach to investigate the role of immune cell populations in the endometrium of patient experiencing reproductive failure. 相似文献
77.
78.
Jean-Raphael Nefussi Agnes Vignery J. Edward Puzas Roland Baron 《Anatomical record (Hoboken, N.J. : 2007)》1982,204(2):105-112
The behavior of fetal rat long bones cultured in vitro according to Raisz's technique (1969) was studied by histomorphometry and autoradiography for a period of four days. The changes were recorded daily both on the trabecular and cortical bone by measuring the bone volume, the number of osteoclasts, and the number of nuclei per osteoclast. Radioactive calcium release was measured and compared to the changes in bone volume and in the number of osteoclasts. An autoradiographic study, using 3H-proline and 3H-thymidine in flash labeling in the medium and 3H-thymidine in follow-up labeling after one injection in vivo was performed to evaluate the bone formation, the cellular proliferation rate and cell differentiation. After four days in culture, an increase in total calcified bone volume was observed which correlatd with changes in the trabecular bone. No significant changes were recorded in the cortical bone. The results showed a good maintenance of the resorption and formation phenomena through an active process of cellular multiplication and differentiation. Undifferentiated cells were labeled in flash label and osteoblast, osteocyte and some osteoclast nuclei were labeled in follow-up studies. 相似文献
79.
P Sgouropoulos J C Baron Y Samson M G Bousser D Comar P Castaigne 《Revue neurologique》1985,141(11):698-705
Using positron emission tomography and the 15O continuous inhalation technique, we have measured the regional cerebral blood flow (rCBF) oxygen extraction fraction (rOEF) and oxygen consumption (rCMRO2) of non-infarcted tissue in six patients with either tight stenosis (N = 3) or occlusion (N = 3) of the trunk of the middle cerebral artery (MCA); these arterial lesions were shown to be persistent on late and/or repeated angiograms. The patients were studied 1 to 6 months after their last cerebral ischemic event. The data were analyzed in 4 cm2 regions of interest (fig. 1) and were compared to age-matched control values. Regional right/left ratios were tested for significance individually by comparison to 95 p. 100 confidence limits found in control subjects. We found a significant reduction in mean rCBF in the affected MCA territory; concomitantly, there was a lesser decrease in rCMRO2 significant only in the peri-sylvian area; this was associated with a moderate but significant increase in rOEF in the same areas (Table II, fig. 2 and 3). Individually, the reduction in rCBF and the increased rOEF were significant in 5/6 and 2/6 patients, respectively (Table III). These data indicate that rCBF is decreased distal to persistent hemodynamic MCA obstruction in most patients. This hypoperfusion appears due in part to a mild degree of cerebral ischemia (as demonstrated by the occurrence of "misery perfusion"), indicating inadequate perfusion pressure distal to the MCA obstruction. This was associated with a metabolic depression of the cortex possibly resulting from either neuronal loss, or deactivation (diaschisis), or long-standing hemodynamic local failure or any combination of the three.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
80.
Effects of extra-intracranial arterial bypass on cerebral blood flow and oxygen metabolism in humans 总被引:6,自引:0,他引:6
Y Samson J C Baron M G Bousser A Rey J M Derlon P David J Comoy 《Stroke; a journal of cerebral circulation》1985,16(4):609-616
Twelve patients, eleven with a carotid obstruction and one with an occlusion of the middle cerebral artery, were studied before and after a successful unilateral extra-intracranial arterial by-pass, (EIAB) using PET and the 15-0 steady-state technique to measure regional cerebral blood flow (CBF), oxygen extraction fraction and oxygen metabolic rate (CMRO2). In the whole group of patients, both CBF and CMRO2 increased significantly on both cerebral hemispheres after EIAB, returning toward control levels defined in age-matched subjects. Mean oxygen extraction fraction, on the other hand, was not affected. Individually, three different effects of EIAB emerged: 1) Alleviation of a state of long standing unilateral "misery-perfusion", as reported earlier; 2) parallel increase of CBF and CMRO2 bilaterally, which appeared due to improvement of a hemodynamic depression of metabolism, the precise mechanism of which remains obscure; 3) Complex, unexpected changes in the CBF-CMRO2 couple again resulting in increases in CMRO2. This metabolic improvement afforded by EIAB in our patients has not been reported before; it suggests that long-standing hemodynamic failure may induce a metabolic depression that is still potentially reversible by surgical revascularization. 相似文献