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991.
Deirdre Cronin-Fenton Anders Kjærsgaard Mette Nørgaard Justyna Amelio Alexander Liede Rohini K. Hernandez Henrik T. Sørensen 《Breast cancer research and treatment》2018,167(2):517-528
Purpose
We developed and validated algorithms to identify metastases and breast cancer recurrence in Danish medical registries. We computed the incidence rate (IR) and hazard ratios (HRs) to evaluate predictors of these outcomes in stage II/III breast cancer patients.Methods
We included all women in Denmark diagnosed during 1999–2011 with regional or stage II/III breast cancer. Demographic, tumor, and treatment data were ascertained from population-based health registries. To facilitate diagnostic work-up of the primary cancer, follow-up began 180 days after diagnosis and continued until recurrence/metastases, death, or 31 December 2012, whichever occurred first. We computed the positive predictive values (PPVs) of recurrence, bone metastases, and visceral metastases using medical records as a gold standard. We calculated the cumulative incidence, IR per 10,000 person years, and used Cox regression to compute the HRs and associated 95% confidence intervals (95% CI) for each outcome.Results
Among 23,478 patients, 7073 had regional stage and 16,405 had stage II/III breast cancer. The PPV for recurrence was 72.6% (95% CI 59.3, 83.3%). The PPVs for bone and visceral metastases were 92.3% (95% CI 69.3–99.2%) and 70.8% (95% CI 51.1, 85.9%), but had low sensitivity. Five-year cumulative incidence of recurrence, bone metastases, and visceral metastases were 18.4, 2.2, and 5.2%, with corresponding 5-year IRs of 540 (95% CI 524, 557), 60 (95% CI 55, 65), and 144 (95% CI 136, 152), respectively. Predictors of recurrence and metastases included age, stage, hormone receptor status, and cancer treatment.Conclusion
Our algorithms show moderate to high PPVs for recurrence and metastases. The IRs of metastases were lower compared with other registry-based cohort studies, so may be underestimated in Danish registries.992.
Cabozantinib is well tolerated in acute myeloid leukemia and effectively inhibits the resistance‐conferring FLT3/tyrosine kinase domain/F691 mutation 下载免费PDF全文
Amir T. Fathi MD Traci M. Blonquist Daniela Hernandez Philip C. Amrein MD Karen K. Ballen MD Malgorzata McMasters MD David E. Avigan MD Robin Joyce MD Emma K. Logan Gabriela Hobbs MD Andrew M. Brunner MD Christelle Joseph Ashley M. Perry Meghan Burke Tanya Behnan Julia Foster Meghan K. Bergeron Jenna A. Moran Aura Y. Ramos Tina T. Som Jessica Rae Kaitlyn M. Fishman Kristin L. McGregor Christine Connolly Donna S. Neuberg Mark J. Levis MD 《Cancer》2018,124(2):306-314
993.
Risk of oral tongue cancer among immunocompromised transplant recipients and human immunodeficiency virus‐infected individuals in the United States 下载免费PDF全文
994.
Manzo J Vazquez MI Cruz MR Hernandez ME Carrillo P Pacheco P 《Physiology & behavior》2000,68(5):611-618
Fertility ratio is defined here as the proportion of females that a male can impregnate after a constant period of in-polygyny living. This ratio was investigated in male rats after denervation of two pelvic floor muscles, the pubococcygeus and iliococcygeus. Denervation was carried out by transecting the somatomotor branch of the pelvic nerve. The lesion did not modify the sexual behavior of males or their overall fertility, but decreased the weight of the ejaculated seminal plug. Consequently, the number of days living in cohabitation to induce pregnancy was increased in lesioned males (approximately 13 days) compared with intact and sham animals (approximately 5 days). These results showed that the fertility ratio was optimal when intact/sham males cohabited with females for two consecutive estrous cycles, but that lesioned males needed up to four cycles to induce most pregnancies. Two hypotheses are raised by our results. The first is that pelvic floor denervation decreases the forceful tension required to expel the semen from the prostatic urethra to the vagina, then an incomplete seminal plug is expelled. The second is that denervation cut afferent fibers that reflexively promote the continence of the semen deposited in the prostatic urethra during seminal emission, allowing some to leak out before ejaculation. The latter hypothesis can also explain the recovery of the fertility ratio in lesioned males. It could be a compensatory mechanism mediated by the pudendal nerve supply to the coccygeus muscle, the other pelvic floor muscle. 相似文献
995.
Transchromosomal mouse embryonic stem cell lines and chimeric mice that contain freely segregating segments of human chromosome 21 总被引:7,自引:0,他引:7
At least 8% of all human conceptions have major chromosome abnormalities and the frequency of chromosomal syndromes in newborns is >0.5%. Despite these disorders making a large contribution to human morbidity and mortality, we have little understanding of their aetiology and little molecular data on the importance of gene dosage to mammalian cells. Trisomy 21, which results in Down syndrome (DS), is the most frequent aneuploidy in humans (1 in 600 live births, up to 1 in 150 pregnancies world-wide) and is the most common known genetic cause of mental retardation. To investigate the molecular genetics of DS, we report here the creation of mice that carry different human chromosome 21 (Hsa21) fragments as a freely segregating extra chromosome. To produce these 'transchromosomal' animals, we placed a selectable marker into Hsa21 and transferred the chromosome from a human somatic cell line into mouse embryonic stem (ES) cells using irradiation microcell-mediated chromosome transfer (XMMCT). 'Transchromosomal' ES cells containing different Hsa21 regions ranging in size from approximately 50 to approximately 0.2 Mb have been used to create chimeric mice. These mice maintain Hsa21 sequences and express Hsa21 genes in multiple tissues. This novel use of the XMMCT protocol is applicable to investigations requiring the transfer of large chromosomal regions into ES or other cells and, in particular, the modelling of DS and other human aneuploidy syndromes. 相似文献
996.
A. J. Torres L. Ortega J. Blanco R. Fernandez-Durango F. Hernandez A. Suarez R. Cuberes J. Sanz J. L. Balibrea 《Virchows Archiv : an international journal of pathology》1987,410(3):165-171
Summary The number of G cells and D cells per area unit and the G cell/D cell ratio was studied in control subjects and patients with duodenal or gastric ulcer. A great inter-individual variation in the population density of both types of cells was observed in the three groups studied. G cell density was significantly decreased in both duodenal and gastric ulcer patients, when compared with controls; whereas no difference in G cell density was seen between duodenal ulcer patients and gastric ulcer patients. However, D cell density was significantly decreased in duodenal ulcer patients when compared with control subjects and gastric ulcer patients. In this latter group, D cell density was also lower than in control subjects. A significant positive linear correlation between G cell number and D cell number was found in the three groups studied. The G cell/D cell ratio was significantly increased in duodenal and gastric ulcer patients when compared with controls. This was mainly due to a decrease in D cell numbers. It is concluded that a local deficit in antral D cells in patients with peptic ulcer may favor the pathogenesis of ulcer disease. 相似文献
997.
The Mycobacterium tuberculosis fadD26 mutant has impaired synthesis of phthiocerol dimycocerosates (DIM) and is attenuated in BALB/c mice. Survival analysis following direct intratracheal infection confirmed the attenuation: 60% survival at 4 months post-infection versus 100% mortality at 9 weeks post-infection with the wild-type strain. The fadD26 mutant induced less pneumonia and larger DTH reactions. It induced lower but progressive production of interferon (IFN)-gamma, interleukin (IL)-4 and tumour necrosis factor (TNF)-alpha. Used as a subcutaneous vaccine 60 days before intratracheal challenge with a hypervirulent strain of M. tuberculosis (Beijing code 9501000), the mutant induced a higher level of protection than did Bacille Calmette-Guérin (BCG). Seventy per cent of the mice vaccinated with the fadD26 mutant survived at 16 weeks after challenge compared to 30% of those vaccinated with BCG. Similarly, there was less tissue damage (pneumonia) and lower colony-forming units (CFU) in the mice vaccinated with the fadD26 mutant compared to the findings in mice vaccinated with BCG. These data suggest that DIM synthesis is important for the pathogenicity of M. tuberculosis, and that inactivation of DIM synthesis can increase the immunogenicity of live vaccines, and increase their ability to protect against tuberculosis. 相似文献
998.
Medeiros M Sharma VK Ding R Yamaji K Li B Muthukumar T Valderde-Rosas S Hernandez AM Muñoz R Suthanthiran M 《Journal of immunological methods》2003,279(1-2):135-142
BACKGROUND: We have shown that measurement of mRNA for cytotoxic attack proteins perforin and granzyme B in urinary cells is a noninvasive means of diagnosing acute rejection of human renal allografts. Urinary cell mRNA studies have yielded useful information in other patient populations such as patients with cancer. The isolation of sufficient and high quality ribonucleic acid (RNA) from urinary cells however is problematic. RNAlater, an RNA stabilization solution, has been reported to optimize RNA isolation from tumor tissues stored at room temperature and from pigment-rich ocular tissues. METHODS: We explored whether the addition of RNAlater to urine cell pellets improves RNA yield, enhances purity and facilitates measurement of low abundance mRNAs. We measured, with the use of real-time quantitative polymerase chain reaction (PCR) assay, levels of expression of a constitutively expressed gene 18S rRNA and mRNA for granzyme B and transforming growth factor-beta(1) (TGF-beta(1)) in urine specimens and renal biopsies obtained from renal allograft recipients. RESULTS: RNA yield (P<0.01, Wilcoxon signed rank test) and the A260/A280 ratio (P<0.01) were both higher with urine cell pellets treated with RNAlater prior to snap freezing compared to cell pellets that were not treated with RNAlater prior to snap freezing. Levels (copy number per 1 microg of total RNA) of 18S rRNA (P<0.02), granzyme B mRNA (P=0.002) and TGF-beta(1) (P=0.02) were all higher with treated urine cell pellets compared to untreated cell pellets. Kruskall-Wallis one way analysis of variance and pair-wise comparisons with Student-Newman-Keuls test showed that the levels of mRNA for granzyme B (P<0.05) and TGF-beta(1) (P<0.05) are significantly different between renal allograft biopsies and untreated urine cell pellets but not between the biopsy specimens and RNAlater-treated urine cell pellets. CONCLUSIONS: The addition of RNAlater to urine cell pellets improves RNA isolation from urinary cells and facilitates measurement of low abundance mRNAs. 相似文献
999.
1000.
Hector J. Hernandez Yong Wang Nia Tzellas Miguel J. Stadecker 《European journal of immunology》1997,27(5):1170-1176
Previous studies have suggested that granulomatous inflammation in schistosomiasis is mediated by CD4+ T helper lymphocytes sensitized to parasite egg antigens. However, CD8+ T cells have also frequently been associated with the immune response to schistosome eggs. To examine more precisely the role of CD4+ and CD8+ T cells in the pathology of the schistosomal infection, we used mice with targeted mutations in major histocompatibility complex (MHC) class II or class I molecules. These mutations lead, respectively, to the virtual absence of CD4+ and CD8+ T cells. The results clearly show that schistosome-infected MHC class II mutant mice failed to form granulomas around parasite eggs. In contrast, infected MHC class I mutant mice displayed characteristic granulomatous lesions that were comparable to those in wild-type control mice. Moreover, lymphoid cells from MHC class II mutant mice were unable to react to egg antigens with either proliferative or cytokine [interferon-gamma, interleukin (IL)-4, IL-10] responses; nor were they able to present egg antigens to specifically sensitized CD4+ T helper cells from infected syngeneic control mice. By comparison, cells from MHC class I mutant mice exercised all these functions in a manner comparable with those from wild-type controls. These observations clearly demonstrate that schistosomal egg granulomas are mediated by MHC class II-restricted CD4+ T helper cells. They also suggest that CD8+ T cells do not become sensitized to egg antigens and play little role, if any, in the pathogenesis of schistosomiasis. 相似文献