Publications
Department of Medicine faculty members published more than 3,600 peer-reviewed articles in 2024.
2013
2013
BACKGROUND
Colorectal adenocarcinoma with depth of invasion ≤1,000 μm from the muscularis mucosa and favorable histology is now considered for local resection. We aimed to examine the strength of evidence for this emerging practice.
METHODS
We searched Medline, Scopus, and Cochrane (1950-2011), then performed a meta-analysis on the risk of lymph node metastasis in nonpedunculated (sessile and nonpolypoid) T1 colorectal cancers. We included studies with nonpedunculated lesions, actual invasion depth, and pathologic factors of interest. Synchronous, polyposis or secondary cancers, and chemoradiation studies were excluded. Our primary outcome was the risk of LNM. We analyzed using Review Manager; we estimated heterogeneity using Cochran Q χ(2) test and I (2). We generated summary risk ratios using a random effects model, performed sensitivity analyses, and evaluated the quality of evidence using GRADEPro.
RESULTS
We identified 209 articles; 5 studies (n = 1213 patients) met the inclusion criteria. The risk of LNM in nonpedunculated ≤1,000 μm is 1.9 % (95 % confidence interval 0.5-4.8 %). The risk for all T1 is 13 % (95 % confidence interval 11.5-15.4 %). Characteristics protective against LNM were ≤1,000 μm invasion, well differentiation, absence of lymphatic and vascular invasion, and absence of tumor budding. We did not detect significant study heterogeneity. The quality of evidence was poor.
CONCLUSIONS
Well-differentiated nonpedunculated T1 colorectal cancer invasive into the submucosa ≤1,000 μm, without lymphovascular involvement or tumor budding, has the lowest risk of nodal metastasis. Importantly, the risk was not zero (1.9 %), and the qualitative formal analysis of data was not strong. As such, endoscopic resection alone may be adequate in select patients with submucosal invasive colorectal cancers, but more studies are needed. Overall, the quality of evidence was poor; data were from small retrospective studies from limited geographic regions.
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CD45 is a receptor-like tyrosine phosphatase that positively regulates BCR signaling by dephosphorylating the inhibitory tyrosine of the Src family kinases. We showed previously that a single point mutation, E613R, introduced into the cytoplasmic membrane-proximal "wedge" domain of CD45 is sufficient to drive a lupus-like autoimmune disease on a susceptible genetic background. To clarify the molecular mechanism of this disease, we took advantage of a unique allelic series of mice in which the expression of CD45 is varied across a broad range. Although both E613R B cells and those with supraphysiologic CD45 expression exhibited hyperresponsive BCR signaling, they did so by opposite regulation of the Src family kinase Lyn. We demonstrated that the E613R allele of CD45 does not function as a hyper- or hypomorphic allele but rather alters the substrate specificity of CD45 for Lyn. Despite similarly enhancing BCR signaling, only B cells with supraphysiologic CD45 expression became anergic, whereas only mice harboring the E613R mutation developed frank autoimmunity on a susceptible genetic background. We showed that selective impairment of a Lyn-dependent negative-regulatory circuit in E613R B cells drove autoimmunity in E613R mice. This demonstrates that relaxing negative regulation of BCR signaling, rather than enhancing positive regulation, is critical for driving autoimmunity in this system.
View on PubMed2013
2013
2013
2013
2013
BACKGROUND
Influenza vaccination among health care personnel (HCP) is a key measure to prevent influenza infection and transmission in health care settings. This study described influenza vaccination coverage among employees in various health care settings in California and examined factors associated with HCP influenza vaccination.
METHODS
This study analyzed data from 111 facilities recruited through statewide invitation. Data on facility characteristics, vaccination programs, and vaccination receipt within and outside facilities were collected using Web-based questionnaires. Employees were defined as all persons in the facility payroll system regardless of patient contact. Facility-level employee vaccination coverage was calculated for 91 facilities.
RESULTS
The mean employee influenza vaccination coverage was 60.7% overall: 64.0% for acute care hospitals (n = 30), 54.7% for long-term care facilities (n = 22), 59.4% for ambulatory surgery centers (n = 8), 58.6% for dialysis centers (n = 25), and 77.2% for physician practices (n = 6). Vaccination promotion methods such as risk-benefit education, personal reminders, and vaccination data tracking and feedback were significantly associated with increased vaccination coverage.
CONCLUSION
The study findings suggest some variations in HCP vaccination coverage by type of health care setting as well as substantial challenges in reaching the Healthy People 2020 goal of 90%. Health care facilities need to use comprehensive promotion methods to improve HCP influenza vaccinations.
View on PubMed2013
BACKGROUND
A travel mode shift to active transportation such as bicycling would help reduce traffic volume and related air pollution emissions as well as promote increased physical activity level. Cyclists, however, are at risk for exposure to vehicle-related air pollutants due to their proximity to vehicle traffic and elevated respiratory rates. To promote safe bicycle commuting, the City of Berkeley, California, has designated a network of residential streets as "Bicycle Boulevards." We hypothesized that cyclist exposure to air pollution would be lower on these Bicycle Boulevards when compared to busier roads and this elevated exposure may result in reduced lung function.
METHODS
We recruited 15 healthy adults to cycle on two routes - a low-traffic Bicycle Boulevard route and a high-traffic route. Each participant cycled on the low-traffic route once and the high-traffic route once. We mounted pollutant monitors and a global positioning system (GPS) on the bicycles. The monitors were all synced to GPS time so pollutant measurements could be spatially plotted. We measured lung function using spirometry before and after each bike ride.
RESULTS
We found that fine and ultrafine particulate matter, carbon monoxide, and black carbon were all elevated on the high-traffic route compared to the low-traffic route. There were no corresponding changes in the lung function of healthy non-asthmatic study subjects. We also found that wind-speed affected pollution concentrations.
CONCLUSIONS
These results suggest that by selecting low-traffic Bicycle Boulevards instead of heavily trafficked roads, cyclists can reduce their exposure to vehicle-related air pollution. The lung function results indicate that elevated pollutant exposure may not have acute negative effects on healthy cyclists, but further research is necessary to determine long-term effects on a more diverse population. This study and broader field of research have the potential to encourage policy-makers and city planners to expand infrastructure to promote safe and healthy bicycle commuting.
View on PubMed2013
OBJECTIVES/HYPOTHESIS
The purpose of this study was to examine factors associated with prophylactic placement of feeding tubes in head and neck cancer patients receiving radiation therapy as a part of treatment using multilevel models that account for patient-, physician-, and institution-level sources of variation.
STUDY DESIGN
A retrospective analysis using binary logistic regression and hierarchical linear models was run to evaluate independent predictors of prophylactic feeding tube placement.
METHODS
Surveillance, Epidemiology, and End Results-Medicare data were used. Head and neck cancer patients diagnosed with locoregionally advanced stage disease from 2000 to 2005 were included in this study (N = 8,306).
RESULTS
Across all models, prophylactic gastrostomy tube placement was found to be more likely in patients who had cancer of the larynx or oropharynx compared with those with cancer of the nasopharynx or oral cavity; who had regional instead of local cancer; who did not receive surgery as a part of treatment, but did receive chemotherapy; and who were divorced, separated, or widowed. Additionally, although practice variation was observed to occur, its overall contribution in predicting prophylactic gastrostomy tube placement was minimal.
CONCLUSIONS
As health care enters an era of patient-centered care, further investigation of the potential role of social support (or lack of social support) in influencing treatment decisions of head and neck cancer patients and providers is warranted.
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