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131.
Francisco Javier Torres Gómez Pilar Jurado Escámez Francisco Javier Torres Olivera 《Clinical & translational oncology》2004,6(8):493-495
Hibernoma is a rare benign tumor arising in brown fat arising in young adults with similar incidence in both sexes. They are generally subcutaneous reaching in some instances a considerable size. The interscapular region, shoulders, head and neck are the main locations, but rare cases have been described in a wide variety of sites. Histologically three types of cells mixed in different proportions corresponding to the stages of maduration of the fatty cells. They are benign tumors with not recurrence after excision. We report a pleural hibernoma, a location not reported previously in the literature. 相似文献
132.
Expression profiling of T-cell lymphomas differentiates peripheral and lymphoblastic lymphomas and defines survival related genes. 总被引:1,自引:0,他引:1
Beatriz Martinez-Delgado Barbara Meléndez Marta Cuadros Javier Alvarez Jose Maria Castrillo Ana Ruiz De La Parte Manuela Mollejo Carmen Bellas Ramon Diaz Luis Lombardía Fatima Al-Shahrour Orlando Domínguez Alberto Cascon Mercedes Robledo Carmen Rivas Javier Benitez 《Clinical cancer research》2004,10(15):4971-4982
PURPOSE: T-Cell lymphomas constitute heterogeneous and aggressive tumors in which pathogenic alterations remain largely unknown. Expression profiling has demonstrated to be a useful tool for molecular classification of tumors. EXPERIMENTAL DESIGN: Using DNA microarrays (CNIO-OncoChip) containing 6386 cancer-related genes, we established the expression profiling of T-cell lymphomas and compared them to normal lymphocytes and lymph nodes. RESULTS: We found significant differences between the peripheral and lymphoblastic T-cell lymphomas, which include a deregulation of nuclear factor-kappaB signaling pathway. We also identify differentially expressed genes between peripheral T-cell lymphoma tumors and normal T lymphocytes or reactive lymph nodes, which could represent candidate tumor markers of these lymphomas. Additionally, a close relationship between genes associated to survival and those that differentiate among the stages of disease and responses to therapy was found. CONCLUSIONS: Our results reflect the value of gene expression profiling to gain insight about the molecular alterations involved in the pathogenesis of T-cell lymphomas. 相似文献
133.
Jaibaji M Brody GS Rodgers K Espinoza T Roda N Maldonado S Pines E diZerega G 《Annals of plastic surgery》2000,44(2):205-210
A minimally invasive model using a manual abrader to induce adhesions in the chicken's central digit is described. The flexor synovial sheath and the profundus tendon were abraded with access through small flaps at the level of the proximal and distal phalanges of the avian long toes. The birds were divided into two groups according to the severity of the induced trauma. Group I birds received an abrasion injury and were euthanized to allow biomechanical testing 5 weeks postoperatively. Group II birds had a more severe abrasion and were euthanized similarly and tested 5 weeks after surgery. Results were compared with nonsurgical controls. Long toe function was evaluated weekly by measuring (1) the range of active flexion of each interphalangeal joint, resolved to total angular range; (2) the grasping ability on graded-diameter perches; and (3) the flexion deficit of the long toe. Postmortem biomechanical properties of the adhesions were measured. There was a significant difference between the unoperated controls and abraded digits of both groups in all parameters (p < 0.001). There was, in addition, a marked change in most of the measured parameters between groups I and II. In group I digits the functional and biomechanical deficit was less than group II. In summary, this animal model of long-segment abrasive injury to the tendon and sheath is a simple and reproducible method to generate adhesions and can be used for the evaluation of treatment modalities for adhesion prevention. 相似文献
134.
Andrés Redondo Sánchez Javier de Castro Carpeño Manuel González Barón 《Clinical & translational oncology》2003,5(5):239-248
Esophageal cancer has a dismal prognosis and the surgical treatment only cures a small percentage of patients. The survival achieved by traditional surgical procedures is being improved with extended resections, but at the cost of greater morbidity. Concurrent radiochemotherapy can obtain results similar to those of surgery. Nowadays, locally advanced esophageal cancer should have a multimodal approach, because neoadjuvant chemotherapy, with or without radiotherapy, has demonstrated to improve the survival of chemosensitive patients. Recently, the role of hyperfractionated radiotherapy and new drugs such as paclitaxel, docetaxel and irinotecan in neoadjuvant treatment is being evaluated. 相似文献
135.
136.
Pilar García-Peña Javier Lucaya G. Michael A. Hendry Philip T. McAndrew Carmina Duran 《Pediatric radiology》1998,28(4):266-270
Background. Two cases of pulmonary sequestration which regressed spontaneously are presented. Objective. To demonstrate the value of imaging studies in the diagnosis and follow-up of some forms of congenital masses of the lung
in asymptomatic patients. Material and methods. We reviewed the clinical records and imaging studies of two asymptomatic children, one newborn and the other 3 months old,
with thoracic masses which demonstrated variable degrees of spontaneous involution. Results. Abdominal ultrasound performed on the newborn with a palpable mass showed a triangular echogenic mass with a large central
feeding vessel arising from the aorta. The mass had disappeared on follow-up US exam performed 6 years later. CT was performed
in the 3-month-old patient with a persistent retrocardiac mass. A soft-tissue density mass in the left pulmonary base with
a large feeding vessel arising from the aorta was visualised on contrast-enhanced CT. Five years later, a new CT scan showed
significant shrinkage of the mass and no vessel. Conclusion. Radiological techniques such as real-time US with Doppler imaging and contrast-enhanced CT may establish the diagnosis of
pulmonary sequestration by demonstrating the mass and its systemic vessel, thereby eliminating the need for more aggressive
imaging procedures. Partial or total disappearance of these masses represents a further example of involutive pathology and
suggests that not all cases of pulmonary sequestration should be surgically treated.
Received: 12 September 1997 Accepted: 18 September 1997 相似文献
137.
Visual inspection with acetic acid for cervical cancer screening outside of low-resource settings. 总被引:2,自引:0,他引:2
Jose Jeronimo Orlando Morales Jorge Horna José Pariona Javier Manrique Jorge Rubi?os Rina Takahashi 《Pan American journal of public health》2005,17(1):1-5
OBJECTIVES: To assess visual inspection with acetic acid (VIA) as a screening tool for use in a well-equipped health center in Peru, to evaluate VIA as an alternative or adjunct to the Papanicolaou (Pap) smear, and to determine if VIA can play a role in settings other than low-resource ones. METHODS: This was a prospective study of 1 921 asymptomatic women living in Lima, Peru, carried out in 1999 and 2000. The study was performed at a cancer center equipped with the latest-generation technology and highly trained oncologists. The women underwent a complete clinical evaluation, including a Pap smear and VIA. Participants with any positive test were referred for colposcopy and biopsy. RESULTS: More women tested positive by VIA than on the Pap smear (6.9% vs. 4.2%; P = 0.0001). There were 35 women with histologic cervical intraepithelial neoplasia grade 1 (CIN 1); of these, 15 were detected by Pap and 20 by VIA (P = 0.4). A diagnosis of CIN 2 or 3 (CIN 2-3) was confirmed in a total of 13 cases; Pap detected 5 of the cases and VIA 11 of the cases (P = 0.06). The positive predictive value for detection of CIN 2+ was 8.3% for VIA and 6.3% for Pap (P = 0.5). Most importantly, while only 2.3% of patients with a positive VIA were lost to follow-up before colposcopy, that was true for 26.3% of the women with a positive Pap smear (P < 0.0001). CONCLUSIONS: VIA is useful for detection of precursor lesions of cervical cancer not only in low-resource settings but also in well-equipped health centers and cancer centers. In these non-low-resource settings, VIA has a positive predictive value comparable to the conventional Pap smear, but it is more likely to achieve earlier diagnosis, follow-up, and treatment than cytology-based screening. 相似文献
138.
Karina Richani Roberto Romero Yeon Mee Kim Enola Cushenberry Eleazar Soto Yu Mi Han Jimmy Espinoza Chong Jai Kim 《The journal of maternal-fetal & neonatal medicine》2006,19(8):509-515
OBJECTIVE: Tissue microarray (TMA) technology allows simultaneous examination of the expression of many molecular markers (protein, mRNA, DNA, etc.) with high-throughput. The application of this technology, to date, has been largely confined to the study of cancer. Placental pathology poses unique challenges because of the size of the organ, its complex anatomy, as well as its histological heterogeneity. The objective of this study was to assess the feasibility and efficiency of TMAs for immunohistochemistry and in situ hybridization of placental tissues. STUDY DESIGN: TMAs were constructed using an automated tissue arrayer. Standard 0.6-mm or 1-mm microarray needles were used. Villous parenchyma, basal plate, and chorioamniotic membranes were targeted in each block. Five mum-thick TMA sections underwent immunohistochemical analysis of both cytoplasmic and nuclear antigens using a panel of antibodies against a variety of cytoplasmic [cytokeratin-7, vascular endothelial growth factor (VEGF), and protein Z], membranous (endoglin), and nuclear (c-fos and c-jun) antigens. mRNA in situ hybridization for surfactant protein A (SP-A) and chromogenic in situ hybridization for the Y chromosome (DYZ1) were also performed. RESULTS: Validation of TMA immunoreactivity demonstrated comparable results with corresponding whole sections. When a two-tiered scoring system (positive/negative) was employed, there was agreement between two and three cores and whole tissue sections (kappa>0.7). When a three-tiered scoring system (negative, weak-positive, or strong-positive) was used, the data from three cores showed the highest agreement with whole tissue sections (kappa >0.7). In situ hybridization experiments for mRNA and DNA were also successful in that the signals were readily detectable. Successful transfer from the donor block to the recipient block differed according to the anatomical compartment. The transfer efficiency of villous parenchyma, basal plate, and chorioamniotic membranes were 96.9% (875/903), 76.7% (115/150), and 75.4% (224/297), respectively. CONCLUSION: TMA is a practical and effective tool for high-throughput molecular analysis of the human placenta. Duplicate and triplicate cores offer agreement with whole tissue sections for two-category distinction immunostaining. TMA also affords relevant results from in situ hybridization experiments for mRNA and DNA. The major advantages are the conservation of tissues and reagents, simultaneous comparison of molecular markers in different anatomical compartments of the placenta, and reduction of experimental error. 相似文献
139.
Sherry A Ferguson F Javier Cisneros B Gough Joseph P Hanig Kimberly J Berry 《Toxicological sciences》2005,87(2):451-459
Oral treatment with the anti-acne drug Accutane (isotretinoin, 13-cis-retinoic acid) has been associated with suicide ideation and depression. Here, depression-like behaviors (i.e., behavioral despair and anhedonia) were quantified in adult Sprague-Dawley rats gavaged daily beginning at postnatal day (PND) 82 with 13-cis-RA (7.5 or 22.5 mg/kg) or all-trans-retinoic acid (10 or 15 mg/kg ). Tested at PND 130-131 in the Forced Swim Test, 7.5 mg/kg 13-cis-RA marginally decreased immobility and slightly increased climb/struggle durations whereas neither all-trans-retinoic acid group differed from controls. Voluntary saccharin solution (0.03%) intake at PND 102-104 and PND 151-153 was not different from controls in any treated group, although all RA-treated groups had lower intakes. Swim speed in a water maze at PND 180 was similar across groups, indicating no RA-induced differences in physical ability. Open field activity was mildly decreased at PND 91 in 7.5 mg/kg-treated males only, but it was within the control range at PND 119, 147, and 175. Thus, at serum levels similar to those in humans receiving the drug, chronic 13-cis-RA treatment did not severely affect depression-like behaviors in rats. These data do not substantiate the hypothesis of 13-cis-RA-induced depression. 相似文献
140.
Sukhwinder S Lakhman Debashis Ghosh Javier G Blanco 《Drug metabolism and disposition》2005,33(2):254-257
Human carbonyl reductase (CBR) activity accounts for a significant fraction of the metabolism of endogenous and xenobiotic carbonyl compounds. It is possible that genetic polymorphisms in CBR1 and CBR3 are key for the wide interindividual variability in the disposition of CBR drug substrates. We pinpointed a single nucleotide polymorphism in CBR3 (CBR3 V244M) that encodes for a V244 to M244 change. Blacks showed a higher frequency of the M244 allele (q = 0.51, n = 49) than did whites (q = 0.31, n = 70; p = 0.003). In addition, DNA variation panels from 10 ethnic groups presented a wide range of CBR3 V244M genotype distributions. Kinetic experiments with the recombinant CBR3 protein variants and menadione revealed that CBR3 M244 has significantly higher V(max) than does CBR3 V244 (V(max) CBR3 M244 = 40.6 +/- 1.3 micromol/min x mg versus V(max) CBR3 V244 = 19.6 +/- 2.0 micromol/min x mg, p = 0.002). In contrast, both isoforms presented similar K(m) values (K(m) CBR3 M244 = 22.9 +/- 2.9 microM versus K(m) CBR3 V244 = 24.6 +/- 3.2 microM, p = 0.43). Assays with NADP(H) demonstrated a higher V(maxNADP(H)) (1.6-fold) and increased catalytic efficiency (V(maxNADP(H))/K(mNADP(H))) for CBR3 M244 compared with CBR3 V244 (p = 0.013). Comparative three-dimensional analyses based on the structure of the homologous porcine carbonyl reductase suggested that the V244M substitution is positioned in a region critical for interactions with the NADP(H) cofactor. These studies demonstrate that the common CBR3 V244M polymorphism encodes for CBR3 isoforms with distinctive enzymatic properties. 相似文献