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61.
Dyson PG Horvath N Joshua D Barrow L Van Holst NG Brown R Gibson J To LB 《Bone marrow transplantation》2000,25(11):1175-1184
A potential problem of autologous transplantation in the treatment of multiple myeloma (MM) is the infusion of tumor cells. CD34+ selection has been used to purge autografts in MM and it is also possible to reduce tumour cell contamination of autografts by cytotoxic drug therapy prior to peripheral blood stem cell (PBSC) collection. To evaluate the effectiveness of a protocol combining multiple cycles of high-dose therapy and CD34+ selection to reduce tumour contamination of PBSC autografts, 34 MM patients were entered on a treatment schedule comprising two sequential cycles of mobilisation, CD34+ selection, and transplantation following high-dose therapy. In the second cycle of mobilisation there was a five-fold reduction in tumour contamination of the stem cell harvest (0.5 x 106/kg) compared with the first cycle (2.5 x 106/kg). In the 97 CD34+ selection procedures performed a median of 185 x 108 mononuclear cells (MNC) were processed yielding a median of 0.98 x 108 CD34+-enriched cells. CD34+ cells were enriched 68-fold from 1. 3% to 88.6%. The median yield of CD34+ cells was 42.2%. Following CD34+ selection the tumour cell contamination of the leukapheresis product was reduced by a median of 2.7 logs. This study demonstrates that in multiple myeloma a significant reduction in the malignant contamination of stem cell autografts can be achieved by combining the in vivo purging effect of cytotoxic therapy with in vitro purging by CD34+ selection. 相似文献
62.
Comparison of myeloma cell contamination of bone marrow and peripheral blood stem cell harvests 总被引:1,自引:0,他引:1
Julianne M. Henry Pamela J. Sykes Michael J. Brisco Luen Bik To Christopher A. Juttner & Alexander A. Morley 《British journal of haematology》1996,92(3):614-619
It could be speculated for patients with myeloma and other lymphoproliferative disorders that peripheral blood stem cells may be preferable to bone marrow for autologous transplantation because they may be less contaminated by neoplastic cells. To test this possibility, the immunoglobulin heavy chain gene rearrangement and limiting dilution polymerase chain reaction were used to sensitively quantify myeloma cells in bone marrow and peripheral blood stem cell collections, taken at a similar time, from eight patients with multiple myeloma. Levels of residual disease in the peripheral blood stem cell harvests were variable and did not reflect the tumour burden in the marrow. Peripheral blood stem cells contained 1.7 to 23 700-fold fewer myeloma cells compared with the bone marrow and would have resulted in reinfusion of 0.08 to 59 480-fold fewer myeloma cells based on total reinfused CFU-GM and 0.24 to 24 700-fold fewer myeloma cells based on total reinfused nucleated cells. Assuming that the proportion of clonogenic myeloma cells is equivalent, peripheral blood stem cells may be better than bone marrow as a source of haemopoietic stem cells for transplantation in multiple myeloma. The clinical follow-up suggested that patients transplanted with peripheral blood stem cells containing a low number of myeloma cells had better disease control than those transplanted with peripheral blood stem cells containing a high number. 相似文献
63.
Paula M. Chilton Diana M. Hadel Thao T. To Thomas C. Mitchell Richard P. Darveau 《Infection and immunity》2013,81(9):3317-3325
Natural heterogeneity in the structure of the lipid A portion of lipopolysaccharide (LPS) produces differential effects on the innate immune response. Gram-negative bacterial species produce LPS structures that differ from the classic endotoxic LPS structures. These differences include hypoacylation and hypophosphorylation of the diglucosamine backbone, both differences known to decrease LPS toxicity. The effect of decreased toxicity on the adjuvant properties of many of these LPS structures has not been fully explored. Here we demonstrate that two naturally produced forms of monophosphorylated LPS, from the mucosa-associated bacteria Bacteroides thetaiotaomicron and Prevotella intermedia, function as immunological adjuvants for antigen-specific immune responses. Each form of mucosal LPS increased vaccination-initiated antigen-specific antibody titers in both quantity and quality when given simultaneously with vaccine antigen preparations. Interestingly, adjuvant effects on initial T cell clonal expansion were selective for CD4 T cells. No significant increase in CD8 T cell expansion was detected. MyD88/Toll-like receptor 4 (TLR4) and TRIF/TLR4 signaling pathways showed equally decreased signaling with the LPS forms studied here as with endotoxic LPS or detoxified monophosphorylated lipid A (MPLA). Natural monophosphorylated LPS from mucosa-associated bacteria functions as a weak but effective adjuvant for specific immune responses, with preferential effects on antibody and CD4 T cell responses over CD8 T cell responses. 相似文献
64.
Kwok-Hung Chan Kelvin K. W. To Betsy W. K. Chan Clara P. Y. Li Susan S. Chiu Kwok-Yung Yuen Pak-Leung Ho 《Journal of clinical microbiology》2013,51(8):2592-2598
Macrolide-resistant Mycoplasma pneumoniae (MRMP) is emerging worldwide and has been associated with treatment failure. In this study, we used pyrosequencing to detect low-frequency MRMP quasispecies in respiratory specimens, and we compared the findings with those obtained by Sanger sequencing and SimpleProbe PCR coupled with a melting curve analysis (SimpleProbe PCR). Sanger sequencing, SimpleProbe PCR, and pyrosequencing were successfully performed for 96.7% (88/91), 96.7% (88/91), and 93.4% (85/91) of the M. pneumoniae-positive specimens, respectively. The A-to-G transition at position 2063 was the only mutation identified. Pyrosequencing identified A2063G MRMP quasispecies populations in 78.8% (67/88) of the specimens. Only 38.8% (26/67) of these specimens with the A2063G quasispecies detected by pyrosequencing were found to be A2063G quasispecies by Sanger sequencing or SimpleProbe PCR. The specimens that could be detected by SimpleProbe PCR and Sanger sequencing had higher frequencies of MRMP quasispecies (51% to 100%) than those that could not be detected by those two methods (1% to 44%). SimpleProbe PCR correctly categorized all specimens that were identified as wild type or mutant by Sanger sequencing. The clinical characteristics of the patients were not significantly different when they were grouped by the presence or absence of MRMP quasispecies, while patients with MRMP identified by Sanger sequencing more often required a switch from macrolides to an alternative M. pneumoniae-targeted therapy. The clinical significance of mutant quasispecies should be investigated further with larger patient populations and with specimens obtained before and after macrolide therapy. 相似文献
65.
Christine E. Wong Jennifer S. Yu David A. Quigley Minh D. To Kuang-Yu Jen Phillips Y. Huang Reyno Del Rosario Allan Balmain 《Genes & development》2013,27(6):670-682
Epithelial–mesenchymal transition (EMT) is thought to be an important, possibly essential, component of the process of tumor dissemination and metastasis. About 20%–30% of Hras mutant mouse skin carcinomas induced by chemical initiation/promotion protocols have undergone EMT. Reduced exposure to TPA-induced chronic inflammation causes a dramatic reduction in classical papillomas and squamous cell carcinomas (SCCs), but the mice still develop highly invasive carcinomas with EMT properties, reduced levels of Hras and Egfr signaling, and frequent Ink4/Arf deletions. Deletion of Hras from the mouse germline also leads to a strong reduction in squamous tumor development, but tumors now acquire activating Kras mutations and exhibit more aggressive metastatic properties. We propose that invasive carcinomas can arise by different genetic and biological routes dependent on exposure to chronic inflammation and possibly from different target cell populations within the skin. Our data have implications for the use of inhibitors of inflammation or of Ras/Egfr pathway signaling for prevention or treatment of invasive cancers. 相似文献
66.
67.
Ranawaka A. P. M. Perera Ronald Ko Owen T. Y. Tsang David S. C. Hui Mike Y. M. Kwan Christopher J. Brackman Esther M. W. To Hui-ling Yen Kathy Leung Samuel M. S. Cheng Kin Ho Chan Karl C. K. Chan Ka-Chi Li Linda Saif Vanessa R. Barrs Joseph T. Wu Thomas H. C. Sit Leo L. M. Poon Malik Peiris 《Journal of clinical microbiology》2021,59(2)
68.
Jacqueline Lorene Bender Rossini Ying Kwan Yue Matthew Jason To Laetitia Deacken Alejandro R Jadad 《Journal of medical Internet research》2013,15(12)
Background
Mobile phones have become nearly ubiquitous, offering a promising means to deliver health interventions. However, little is known about smartphone applications (apps) for cancer.Objective
The purpose of this study was to characterize the purpose and content of cancer-focused smartphone apps available for use by the general public and the evidence on their utility or effectiveness.Methods
We conducted a systematic review of the official application stores for the four major smartphone platforms: iPhone, Android, Nokia, and BlackBerry. Apps were included in the review if they were focused on cancer and available for use by the general public. This was complemented by a systematic review of literature from MEDLINE, Embase, and the Cochrane Library to identify evaluations of cancer-related smartphone apps.Results
A total of 295 apps from the smartphone app stores met the inclusion criteria. The majority of apps targeted breast cancer (46.8%, 138/295) or cancer in general (28.5%, 84/295). The reported app purpose was predominantly to raise awareness about cancer (32.2%, 95/295) or to provide educational information about cancer (26.4%, 78/295), followed by apps to support fundraising efforts (12.9%, 38/295), assist in early detection (11.5%, 34/295), promote a charitable organization (10.2%, 30/295), support disease management (3.7%, 11/295), cancer prevention (2.0%, 6/295), or social support (1.0%, 3/295). The majority of the apps did not describe their organizational affiliation (64.1%, 189/295). Apps affiliated with non-profit organizations were more likely to be free of cost (χ2 1=16.3, P<.001) and have a fundraising or awareness purpose (χ2 2=13.3, P=.001). The review of the health literature yielded 594 articles, none of which reported an evaluation of a cancer-focused smartphone application.Conclusions
There are hundreds of cancer-focused apps with the potential to enhance efforts to promote behavior change, to monitor a host of symptoms and physiological indicators of disease, and to provide real-time supportive interventions, conveniently and at low cost. However, there is a lack of evidence on their utility, effectiveness, and safety. Future efforts should focus on improving and consolidating the evidence base into a whitelist for public consumption. 相似文献69.
Yoshifumi Nishi Chika Ogami Yasuhiro Tsuji Hitoshi Kawasuji Harumi Yamada Shin Kawai Ippei Sakamaki Hideto To Yoshihiro Yamamoto 《Journal of infection and chemotherapy》2021,27(2):165-171
IntroductionAims of this study were (a) to assess the development ratio of hyponatremia during treatment with linezolid and (b) to evaluate the relationship between the risk of hyponatremia and linezolid exposure and patient background.MethodClinical data including linezolid serum concentrations and serum sodium values were collected at Toyama University Hospital and Kyorin University Hospital. Data from 89 patients were used for the analysis, and a nadir serum sodium level ≤130 mmol/L during the treatment with linezolid was defined as hyponatremia. Mann-Whitney's U test was used to evaluate the effects of the area under the time-concentration curve (AUC) of linezolid at the nadir sodium level, clinical characteristics (e.g. laboratory data), and baseline serum sodium levels on the development of hyponatremia.ResultsThe hyponatremia was occurred in 21 of 89 patients (23.6%). Data are compared for baseline and nadir serum sodium levels of patients with and without hyponatremia. In both groups, nadir serum sodium levels were significantly different from those of the baseline values (P < 0.05). The values of AUC0-12, accumulated AUC, baseline serum sodium levels and age were significantly different between patients with and without hyponatremia (P < 0.05).ConclusionsLinezolid exposure, age, and baseline sodium levels were detected as the risk factors for linezolid-related hyponatremia. Our findings suggest that regular monitoring of serum sodium levels is desirable during treatment with linezolid, especially for the elderly and patients with low serum sodium levels before the start of linezolid administration. 相似文献
70.
Jeremy YC Teoh Steffi KK Yuen James HL Tsu Charles KW Wong Brian SH Ho Ada TL Ng Wai-Kit Ma Kwan-Lun Ho Ming-Kwong Yiu 《Asian journal of andrology》2015,17(5):821-825
We investigated the prostate cancer detection rates upon transrectal ultrasound (TRUS)-guided biopsy in relation to digital rectal examination (DRE) and prostate-specific antigen (PSA), and risk factors of prostate cancer detection in the Chinese population. Data from all consecutive Chinese men who underwent first TRUS-guided prostate biopsy from year 2000 to 2013 was retrieved from our database. The prostate cancer detection rates with reference to DRE finding and PSA level of < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 were investigated. Multivariate logistic regression analyses were performed to investigate for potential risk factors of prostate cancer detection. A total of 2606 Chinese men were included. In patients with normal DRE, the cancer detection rates were 8.6%, 13.4%, 21.8%, 41.7% and 85.2% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. In patients with abnormal DRE, the cancer detection rates were 12.4%, 30.2%, 52.7%, 80.6% and 96.4% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. Older age, smaller prostate volume, larger number of biopsy cores, presence of abnormal DRE finding and higher PSA level were associated with increased risk of prostate cancer detection upon multivariate logistic regression analyses (P < 0.001). Chinese men appeared to have lower prostate cancer detection rates when compared to the Western population. Taking the different risk factors into account, an individualized approach to the decision of TRUS-guided biopsy can be adopted. 相似文献