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Alejandra Gordillo Hernández Eduardo Dominguez-Adame Lanuza Auxiliadora Cano Matias Rosario Perez Huertas Katherine Maria Gallardo Rodriguez Purificacion Gallinato Perez Fernando Oliva Mompean 《World journal of gastrointestinal surgery》2015,7(8):170-173
Gangliocytic paragangliomas are rare tumors that almost exclusively occur within the second portion of the duodenum. Although these tumors generally have a benign clinical course, they have the potential to recur or metastasize to regional lymph nodes. The case report presented here describes a 57-year-old female patient with melena, progressive asthenia, anemia, and a mass in the second-third portion of the duodenum that was treated by local excision. The patient was diagnosed with a friable bleeding tumor. The histologic analysis showed that the tumor was a 4 cm gangliocytic paraganglioma without a malignant cell pattern. In the absence of local invasion or distant metastasis, endoscopic resection represents a feasible, curative therapy. Although endoscopic polypectomy is currently considered the treatment of choice, it is not recommended if the size of the tumor is > 3 cm and/or there is active or recent bleeding. Patients diagnosed with a gangliocytic paraganglioma should be closely followed-up for possible local recurrence. 相似文献
3.
Hao Wu Colin Webber Carmen Otero Fuentes Robert Bensen Karen Beattie Jonathan D Adachi Xiaoming Xie Farhang Jabbari David R Levy 《Journal l'Association canadienne des radiologistes》2007,58(3):167-175
OBJECTIVES: 1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups. METHODS: Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion. RESULTS: Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects. CONCLUSION: The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities. 相似文献
4.
J San Cristóbal I Cearra B Otero T Martínez-Astorquiza H Marín I García-Alonso 《Revista española de enfermedades digestivas》2007,99(1):25-32
OBJECTIVE: An intestinal reperfusion study with two aims: a) to assess the usefulness of intestinal capillary blood flow measurement by laser-Doppler for intestinal reperfusion studies; and b) to compare the effects of racemic and levo forms of folinic acid in treating the syndrome. EXPERIMENTAL DESIGN: A murine model of intestinal ischemia by completely clamping the superior mesenteric artery for 90 minutes. A comparison was made of three treatment groups: saline, folinic acid, and levo-folinic acid. The following factors were analyzed: changes in biochemical parameters (levels of creatine kinase, lactic dehydrogenase, and alkaline phosphatase at 60 minutes, and at two and seven days after restoring blood flow), capillary flow in the jejunum and ileum by laser-Doppler (during ischemia and after the first hour of reperfusion), intestinal mucosa injury, and survival curve. RESULTS: Laser-Doppler provided reliable data on how the different treatments affected capillary flow during intestinal reperfusion. Levo-folinic acid improved capillary flow in the ileum after 25 minutes of reperfusion, and also reduced mucosal injury in the same stretch of intestine by the seventh day post-reperfusion (p<0.05). On the other hand, it produced an initial increase in serum enzymes during reperfusion, and did not modify survival. CONCLUSIONS: The changes observed in intestinal capillary blood flow measurement by laser-Doppler have similarities with the effects of drugs on pathological mucosal changes. We could not prove that the levo form of folinic acid has a stronger protective effect versus racemic folinic acid in intestinal ischemia-reperfusion syndrome. 相似文献
5.
G Falero I Rodríguez J Sarracent A J Otero B L Rodríguez A Rojas E Ochoa 《Hybridoma》1992,11(6):815-823
We report the generation of murine triomas by fusing splenocytes from mice previously immunized with HBsAg ay-subtype and a hybridoma, secreting anti-HBsAg ad-subtype monoclonal antibody, which was rendered HGPRT- by induced mutagenesis with N-methyl-N'nitro-N-nitrosoguanidine. The fusion yielded a 83.8% of hybrids showing the antigen specificity of the parental hybridoma and a 16.1% of bi-specific monoclonal antibodies. One of them, coded as 1C8A5, showing a heavy chain isotype (IgG1/IgG2b) was used as capture reagent in an ultramicro-ELISA. As little as 0.78 I.U. of both HBsAg ad- and ay-subtypes could be realiably detected. 相似文献
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We compared several pharmacological and enzymatic effects induced by 11 snake venoms from seven species, six of them from different geographic areas of Antioquia and Choco, north-west of Colombia, South America (Bothrops atrox, B. nasutus, B. schlegelii, B. punctatus, Lachesis muta, Micrurus mipartitus), and Crotalus durissus terrificus venom, from specimens captured in other provinces of the country (Tolima, Huila, Meta and Atlantico). Differences were observed in edema-forming, hemorrhage, defibrination, indirect hemolysis, myonecrosis, proteolysis and lethal activity between venoms from different genera or species, as well as according to the geographic area of origin in B. atrox and B. nasutus snake venoms. Bothrops venoms, in particular B. atrox and L. muta, produced major local effects. All of the venoms, including M. mipartitus, had myotoxic effects. The most defibrinating venoms were B. atrox, L. muta, B. punctatus and C. d. terrificus. All of the venoms had indirect hemolytic activity; the venom of M. mipartitus being greatest. The most lethal venoms were those of C. d. terrificus and M. mipartitus. Within Bothrops species, the venom of B. schlegelii was the least active in terms of local and systemic pathologic effects. 相似文献
8.
Maria Cabrerizo Juan E Echevarria Almudena Otero Paloma Lucas Gloria Trallero 《Journal of clinical virology》2008,43(3):323-327
BACKGROUND: Coxsackievirus A24 variant is one of the major etiological agents involved in acute haemorrhagic conjunctivitis. STUDY DESIGN: An outbreak of acute hemorrhagic conjunctivitis occurred in the Southeast of Spain between September and November 2004. Cellular and molecular methods were used to identify and characterize the viral agent associated with the epidemic. RESULTS: Enterovirus was detected in the conjunctival swabs of 35 patients. None of the viruses isolated could be typed by conventional neutralization assays; however, amplification and sequencing of the 3'-end VP1 region of 19 of the samples identified coxsackievirus A24 variant as the serotype causing the outbreak. Phylogenetic analysis of the 5'-half VP1 region of the genome revealed that Spanish sequences, like other strains isolated during outbreaks of hemorrhagic conjunctivitis in American and African countries in 2003 and 2004, were closely related to the isolates detected in Korea (2002), thus proving their worldwide spread. CONCLUSIONS: This is the first report of an epidemic of acute hemorrhagic conjunctivitis due to a coxsackievirus A24 variant in Spain. Molecular typing in combination with phylogenetic analysis is useful to study the enterovirus epidemiology associated with epidemics. 相似文献
9.
Silva ML Land MG Maradei S Otero L Veith M Brito G Klumb C Fernandez T Pombo-de-Oliveira MS 《Cancer Genetics and Cytogenetics》2002,135(1):101-102
We report a new case of therapy-related acute myeloid leukemia in a child with Langerhans cell histiocytosis. This patient was previously treated with a protocol of multidrug chemotherapy, containing a relatively low dose of etoposide (total dose of 900/m(2)). Twenty-six months after the end of the therapy, the patient returned to the hospital with fever and anemia. The white blood cell count was 53 x 10(9)/L. The bone marrow examination showed massive infiltration with French-American-British acute myeloid leukemia classification M4 blast cells. The patient did not respond to an intensive treatment with high dose ARA-C and idarubicin. He died 6 months later. The cytogenetic abnormality of the blast cells was a t(11;11)(p13 -15;q23), that has not been described before in a secondary leukemia case. 相似文献
10.
Calarota SA Otero M Hermanstyne K Hermanstayne K Lewis M Rosati M Felber BK Pavlakis GN Boyer JD Weiner DB 《Journal of immunological methods》2003,279(1-2):55-67
The enzyme-linked immune spot (ELISPOT) assay is receiving increased attention as a means for quantifying antigen-specific CD8 T-cell responses in rhesus macaques. Further improving the sensitivity of this assay could aid in the evaluation of vaccine candidates and/or immune therapeutic candidates. Interleukin (IL)-15 has been demonstrated to stimulate expansion of human immunodeficiency virus (HIV)-specific cytotoxic T lymphocytes (CTL) and to regulate homeostatic proliferation of CD8+ memory cells. We evaluated the in vitro effect of IL-15 to increase the detection of interferon-gamma (IFN-gamma) production by antigen-specific stimulated lymphocytes from a group of rhesus macaques exposed to simian-human immunodeficiency virus (SHIV) and a second group infected with SIVmac251, before and after antiretroviral treatment (ART). Results from these studies demonstrate that the presence of IL-15 during stimulation in a peptide-based ELISPOT assay greatly enhanced IFN-gamma production in both SHIV and simian immunodeficiency virus (SIV)-infected macaques. IFN-gamma production was mainly mediated by CD8 lymphocytes. The optimal concentrations of IL-15 that give enhancement of IFN-gamma production to specific antigen, without a significant increase in the spontaneous IFN-gamma release, ranged from 0.5 to 2.5 ng/ml. The mean number of IFN-gamma spots was increased 3.1- to 3.6-fold in response to SIV gag or HIV env peptide pools, respectively, in peripheral blood mononuclear cells (PBMC) from SHIV-infected macaques. Similarly, in SIV-infected macaques, IL-15 increased the mean number of IFN-gamma spots 2.7-fold in response to both SIV gag and env peptide pools. In samples obtained after ART in the same macaques, the increase factor was 2.5 for SIV gag and 1.8 for the env peptide pools. Thus, the sensitivity of the ELISPOT assay can be enhanced by addition of IL-15. This modified assay will be useful for detection of low frequencies of IFN-gamma producing cells in rhesus macaques. 相似文献