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21.
The ability of the 134-2C2 monoclonal antibody (mAb; CD26) to transmit an activation signal and to affect T cell proliferation has been studied. The 134-2C2 mAb, although not being mitogenic by itself, is able to increase the proliferation of purified T cells in the presence of exogenous interleukin 2 (IL2) or phorbol 12-myristate 13-acetate (PMA). No effect of our mAb was observed on the proliferation of T cells induced by other stimuli such as Sepharose-bound CD3 mAb, phytohemagglutinin or calcium ionophore. Since the co-stimulatory effect of 134-2C2 mAb on PMA-induced T cell proliferation was strongly inhibited by an anti-Tac antibody, its involvement on the IL2/IL2 receptor pathway was investigated. An increased IL2 secretion in T cells cultured with PMA plus 134-2C2 mAb was observed and Northern blot analysis showed that the mAb 134-2C2 acts synergistically with PMA favoring the induction of both IL2 and interferon-γ mRNA synthesis, as well as the enhancement of IL2 receptor and transferrin receptor mRNA expression. Studies on mechanisms implicated in signal transduction showed that 134-2C2 mAb modifies neither intracellular calcium levels nor phosphoinositide breakdown. Additionally, no effect was exerted on protein kinase C translocation. These data suggest that the CD26 antigen is involved in T cell activation in an IL2/IL2 receptor-dependent pathway.  相似文献   
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Aránzazu Caballero-Marcos  Magdalena Salcedo  Roberto Alonso-Fernández  Manuel Rodríguez-Perálvarez  María Olmedo  Javier Graus Morales  Valentín Cuervas-Mons  Alba Cachero  Carmelo Loinaz-Segurola  Mercedes Iñarrairaegui  Lluís Castells  Sonia Pascual  Carmen Vinaixa-Aunés  Rocío González-Grande  Alejandra Otero  Santiago Tomé  Javier Tejedor-Tejada  José María Álamo-Martínez  Luisa González-Diéguez  Flor Nogueras-Lopez  Gerardo Blanco-Fernández  Gema Muñoz-Bartolo  Francisco Javier Bustamante  Emilio Fábrega  Mario Romero-Cristóbal  Rosa Martin-Mateos  Julia Del Rio-Izquierdo  Ana Arias-Milla  Laura Calatayud  Alberto A. Marcacuzco-Quinto  Víctor Fernández-Alonso  Concepción Gómez-Gavara  Jordi Colmenero  Patricia Muñoz  José A. Pons  the Spanish Society of Liver Transplantation 《American journal of transplantation》2021,21(8):2876-2884
The protective capacity and duration of humoral immunity after SARS-CoV-2 infection are not yet understood in solid organ transplant recipients. A prospective multicenter study was performed to evaluate the persistence of anti-nucleocapsid IgG antibodies in liver transplant recipients 6 months after coronavirus disease 2019 (COVID-19) resolution. A total of 71 liver transplant recipients were matched with 71 immunocompetent controls by a propensity score including variables with a well-known prognostic impact in COVID-19. Paired case–control serological data were also available in 62 liver transplant patients and 62 controls at month 3 after COVID-19. Liver transplant recipients showed a lower incidence of anti-nucleocapsid IgG antibodies at 3 months (77.4% vs. 100%, < .001) and at 6 months (63.4% vs. 90.1%, < .001). Lower levels of antibodies were also observed in liver transplant patients at 3 (= .001) and 6 months (< .001) after COVID-19. In transplant patients, female gender (OR = 13.49, 95% CI: 2.17–83.8), a longer interval since transplantation (OR = 1.19, 95% CI: 1.03–1.36), and therapy with renin–angiotensin–aldosterone system inhibitors (OR = 7.11, 95% CI: 1.47–34.50) were independently associated with persistence of antibodies beyond 6 months after COVID-19. Therefore, as compared with immunocompetent patients, liver transplant recipients show a lower prevalence of anti-SARS-CoV-2 antibodies and more pronounced antibody levels decline.  相似文献   
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Journal of Community Health - Little is known about Community Health Workers (CHWs) who work in non-clinical settings to provide sexual health support around HIV, viral hepatitis, and other...  相似文献   
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PURPOSE: To allow the longitudinal investigation of molecular events associated with the progression of human hepatocellular carcinoma (HCC), we sought to develop a murine model by orthotopic implantation of tumor fragments obtained from patients diagnosed at early stage. EXPERIMENTAL DESIGN: Tumor pieces (2 x 2 mm) were implanted on the liver surface of nu/nu mice. After xenograft growing, subsequent passages were performed to achieve long-term implant viability. Isolation of tumoral hepatocytes was done to establish new cell lines. HCC characteristics, proliferation rate, apoptotic index (terminal deoxynucleotidyl transferase-mediated nick end labeling), and expression of cell-cycle regulators (cyclins E and A, p21(Cip1), p27(Kip1), p16(INK4a), pRb, and p53) were assessed by Western Blot and immunohistochemistry, to correlate them with tumor progression. RESULTS: Five (50%) of the 10 primary HCCs resulted in small slow-growing liver implants. Three of them are viable after 48 months, whereas the remaining two survived for 15 and 13 months. Xenografts throughout passages exhibited a more aggressive phenotype with a poorer degree of differentiation, intense proliferation, moderate apoptosis, cell-cycle deregulation, p53 alterations, microvascular invasion, and dissemination. In one single passage, we observed critical growth delay, which was associated with significant p27(kip1) overexpression. We established the anchor-free growing BCLC-9 cell line from one xenograft. This has gains of chromosomes 7, 5p, 6q, and 9q, is hepatitis B virus-DNA positive, does not secrete alpha-fetoprotein, and has TP53 missense mutations in codons 192 and 242. CONCLUSIONS: The orthotopic implantation of early HCC fragments in nude mice provides a useful model to investigate the mechanisms of human HCC evolution and to establish new cell lines.  相似文献   
26.
Adult male Long-Evans rats (250-350 g) received control vehicles, 3,3'-iminodipropionitrile (IDPN, 400 mg kg(-1) day(-1)), allylnitrile (50 mg kg(-1) day(-1)), cis-crotononitrile (110 mg kg(-1) day(-1)), trans-crotononitrile (250 mg kg(-1) day(-1)), or 2,4-hexadienenitrile (300 mg kg(-1) day(-1)), i.p., for 3 consecutive days. Rats treated with IDPN, allylnitrile, and cis-crotononitrile developed the ECC (excitation with circling and choreiform movements) syndrome, whereas those treated with trans-crotononitrile and hexadienenitrile exhibited a different syndrome, characterized by faltering movements. On quantitative analysis, IDPN, allylnitrile, and cis-crotononitrile induced high scores in a test battery for vestibular dysfunction and hyperactivity in the open field, but they did not significantly decrease stride length. Hexadienenitrile and trans-crotononitrile did not increase the vestibular scores or the locomotor activity, but they caused a marked decrease in stride length; they also decreased holding time on a vertical ladder. In brain and spinal cord tissue from rats exposed to IDPN, allylnitrile, or cis-crotononitrile, Fluoro-Jade B, a selective stain for degenerating neurons, did not reveal any labeling other than that of nerve terminals in the glomeruli of the olfactory bulbs, indicating degeneration of the olfactory mucosa. With the same stain, rats exposed to trans-crotononitrile or hexadienenitrile showed a common pattern of selective neurotoxicity; major targets were the inferior olive and the piriform cortex. Hexadienenitrile did not cause hair cell degeneration in the vestibular and auditory sensory epithelia. Present and previous data indicate that neurotoxic nitriles induce one or the other of two different motor syndromes, through either vestibular hair cell degeneration or neuronal degeneration of the inferior olive.  相似文献   
27.
PURPOSE: To investigate whether allogeneic stem-cell transplantation (allo-SCT) may overcome the negative impact of unmutated VH genes in the outcome of patients with chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: We analyzed the outcome of patients who underwent SCT according to their VH mutational status. RESULTS: Thirty-four patients (14 allo-SCT and 20 autologous SCT [auto-SCT]) presented unmutated VH genes and 16 patients presented mutated VH genes (nine allo-SCT and seven auto-SCT). Tumoral burden pre-SCT was significantly higher in the allo-SCT patients independent of the VH mutational status. The risk of relapse was significantly higher after auto-SCT (5-year risk, 61%; 95% CI, 44% to 84%) than after allo-SCT (5-year risk 12%, 95% CI, 3% to 44%; P < .05). In the unmutated group, 13 of 20 auto-SCT and two of 14 allo-SCT patients experienced disease progression, with a risk of relapse at 5 years of 66% (95% CI, 48% to 93%) v 17% (95% CI, 5% to 60%), respectively (P = .01). CONCLUSION: These results show that allo-SCT may overcome the unfavorable effect of unmutated VH genes in patients with CLL.  相似文献   
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Introduction

Microinvasive carcinoma represents a subgroup within cervical cancer that is characterized by having a good prognosis and the possibility of treatment through conservative approaches.

Material and methods

We studied data from 60 patients treated at our hospital from 1994 to 2001. The diagnosis was made by the loop electrosurgical excision procedure (LEEP).

Results

Of all treated patients, 83.3% had stage IA1 carcinomas and 16.6% were in stage IA2. All tumors were squamous carcinomas, except one, which was a mucinous adenocarcinoma. Forty patients with stage IA1 tumors underwent total hysterectomy, whilst the remainder were treated by LEEP or, in two patients, through a cervical stump excision. Except for one patient with contraindications for surgery, all IA2 patients underwent radical surgery consisting of radical hysterectomy with bilateral iliac lymphadenectomy. Relapse occurred in only one patient with a stage IA1 tumor, who then underwent colpectomy.

Conclusions

Our data support the current trend of increasing the use of conservative treatments and confirm the excellent prognosis of this neoplasm.  相似文献   
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