Wenjun Li

Bio: Wenjun Li is an academic researcher from University of Massachusetts Medical School. The author has contributed to research in topics: Women's Health Initiative & Population. The author has an hindex of 56, co-authored 218 publications receiving 10557 citations. Previous affiliations of Wenjun Li include Tufts Medical Center & Tufts University.

Prevention of experimental choroidal neovascularization with intravitreal anti-vascular endothelial growth factor antibody fragment.

Abstract: Objective To evaluate the safety and efficacy of intravitreal injections of an antigen-binding fragment of a recombinant humanized monoclonal antibody directed toward vascular endothelial growth factor (rhuFab VEGF) in a monkey model of choroidal neovascularization (CNV). Methods In phase 1 of the study, each animal received intravitreal injections, 500 µg per eye, of rhuFab VEGF in one eye (prevention eye), while the contralateral eye received rhuFab VEGF vehicle (control eye) at 2-week intervals. On day 21, laser photocoagulation was performed to induce CNV. In phase 2, the vehicle-treated eye was crossed over and both eyes received 500 µg of rhuFab VEGF beginning 21 days following laser-induced injury at days 42 and 56. The eyes were monitored by ophthalmic examinations, color photographs, and fluorescein angiography. Results rhuFab VEGF did not cause any ocular hemorrhages. All eyes treated with rhuFab VEGF developed acute anterior chamber inflammation within 24 hours of the first injection that resolved within 1 week, and this inflammation was less severe with subsequent injections. The incidence of CNV, defined angiographically, was significantly lower in the prevention eyes than the control eyes ( P P = .001). Conclusions Intravitreal rhuFab VEGF injections prevented formation of clinically significant CNV in cynomolgus monkeys and decreased leakage of already formed CNV with no significant toxic effects. Clinical Relevance This study provides the nonclinical proof of principle for ongoing clinical studies of intravitreally injected rhuFab VEGF in patients with neovascular age-related macular degeneration.

Better Physician-Patient Relationships Are Associated with Higher Reported Adherence to Antiretroviral Therapy in Patients with HIV Infection

Abstract: BACKGROUND: There is little evidence to support the widely accepted assertion that better physician-patient relationships result in higher rates of adherence with recommended therapies. OBJECTIVE: To determine whether and which aspects of a better physician-patient relationship are associated with higher rates of adherence with antiretroviral therapies for persons with HIV infection. DESIGN: Cross-sectional analysis. SETTING: Twenty-two outpatient HIV practices in a metropolitan area. PARTICIPANTS: Five hundred fifty-four patients with HIV infection taking antiretroviral medications. MEASUREMENTS: We measured adherence using a 4-item self-report scale (α=0.75). We measured core aspects of physician-patient relationships using 6 previously tested scales (general communication, HIV-specific information, participatory decision making, overall satisfaction, willingness to recommend physician, and physician trust; α>0.70 for all) and 1 new scale, adherence dialogue (α=0.92). For adherence dialogue, patients rated their physician at understanding and solving problems with antiretroviral therapy regimens. RESULTS: Mean patient age was 42 years, 15% were female, 73% were white, and 57% reported gay or bisexual sexual contact as their primary HIV risk factor. In multivariable models that accounted for the clustering of patients within physicians’ practices, 6 of the 7 physician-patient relationship quality variables were significantly (P<.05) associated with adherence. In all 7 models worse adherence was independently associated (P<.05) with lower age, not believing in the importance of antiretroviral therapy, and worse mental health. CONCLUSIONS: This study showed that multiple, mutable dimensions of the physician-patient relationship were associated with medication adherence in persons with HIV infection, suggesting that physician-patient relationship quality is a potentially important point of intervention to improve patients’ medication adherence. In addition, our data suggest that it is critical to investigate and incorporate patients’ belief systems about antiretroviral therapy into adherence discussions, and to identify and treat mental disorders.

Outdoor falls among middle-aged and older adults: a neglected public health problem

Abstract: Objectives. Although risk factors for indoor falls among older individuals have been well studied, little is known about the etiology of outdoor falls. We examined risk factors for outdoor falls among middle-aged and older adults.Methods. We analyzed data on the most recent fall during the past year among participants aged 45 years and older in the control group (N=2193) of a case–control study of fractures. The study was conducted at 5 Northern California Kaiser Permanente Medical Centers between 1996 and 2001.Results. Falls occurred outdoors more often than indoors among most age groups. Study participants who reported more leisure-time physical activity had a higher risk for outdoor falls, and participants who were in poorer health had a greater risk for indoor falls. Most outdoor falls (73%) were precipitated by environmental factors, such as uneven surfaces and tripping or slipping on objects, and usually occurred on sidewalks, curbs, and streets. Walking (47.3%) was the most common fall-related acti...

The biology of VEGF and its receptors.

Abstract: Vascular endothelial growth factor (VEGF) is a key regulator of physiological angiogenesis during embryogenesis, skeletal growth and reproductive functions. VEGF has also been implicated in pathological angiogenesis associated with tumors, intraocular neovascular disorders and other conditions. The biological effects of VEGF are mediated by two receptor tyrosine kinases (RTKs), VEGFR-1 and VEGFR-2, which differ considerably in signaling properties. Non-signaling co-receptors also modulate VEGF RTK signaling. Currently, several VEGF inhibitors are undergoing clinical testing in several malignancies. VEGF inhibition is also being tested as a strategy for the prevention of angiogenesis, vascular leakage and visual loss in age-related macular degeneration.

Angiogenesis in cancer, vascular, rheumatoid and other disease

Abstract: Recent discoveries of endogenous negative regulators of angiogenesis, thrombospondin, angiostatin and glioma-derived angiogenesis inhibitory factor, all associated with neovascularized tumours, suggest a new paradigm of tumorigenesis. It is now helpful to think of the switch to the angiogenic phenotype as a net balance of positive and negative regulators of blood vessel growth. The extent to which the negative regulators are decreased during this switch may dictate whether a primary tumour grows rapidly or slowly and whether metastases grow at all.