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Featured researches published by Yajarayma J. Tang-Feldman.


Telemedicine Journal and E-health | 2014

Sustained Effects of a Nurse Coaching Intervention via Telehealth to Improve Health Behavior Change in Diabetes

Heather M. Young; Sheridan Miyamoto; Deborah Ward; Madan Dharmar; Yajarayma J. Tang-Feldman; Lars Berglund

BACKGROUND Diabetes educators and self-management programs are scarce in rural communities, where diabetes is the third highest-ranking health concern. The goal of this study was to evaluate the benefits of nurse telehealth coaching for persons with diabetes living in rural communities through a person-centered approach using motivational interviewing (MI) techniques. MATERIALS AND METHODS A randomized experimental study design was used to assign participants to receive either nurse telehealth coaching for five sessions (intervention group) or usual care (control group). Outcomes were measured in both groups using the Diabetes Empowerment Scale (DES), SF-12, and satisfaction surveys. Mean scores for each outcome were compared at baseline and at the 9-month follow-up for both groups using a Students t test. We also evaluated the change from baseline by estimating the difference in differences (pre- and postintervention) using regression methods. RESULTS Among the 101 participants included in the analysis, 51 received nurse telehealth coaching, and 50 received usual care. We found significantly higher self-efficacy scores in the intervention group compared with the control group based on the DES at 9 months (4.03 versus 3.64, respectively; p<0.05) and the difference in difference estimation (0.42; p<0.05). CONCLUSIONS The nurse MI/telehealth coaching model used in this study shows promise as an effective intervention for diabetes self-management in rural communities. The sustained effect on outcomes observed in the intervention group suggests that this model could be a feasible intervention for long-term behavioral change among persons living with chronic disease in rural communities.


Proceedings of the National Academy of Sciences of the United States of America | 2013

Murine natural killer cell licensing and regulation by T regulatory cells in viral responses

Can M. Sungur; Yajarayma J. Tang-Feldman; Erik Ames; Maite Alvarez; Mingyi Chen; Dan L. Longo; Claire Pomeroy; William J. Murphy

Natural killer (NK) cells show differential functionality based on their capability of binding to self-MHC consistent with licensing. Here we show in vivo confirmation of the physiologic effects of licensing with differential effects of NK subsets on anti-murine cytomegalovirus (anti-MCMV) responses after syngeneic hematopoietic stem cell transplantation (HSCT) or regulatory T-cell (Treg) depletion. After HSCT, depletion of licensed NK cells led to far greater viral loads in target organs early after infection compared with nondepleted and unlicensed depleted mice. There was a preferential expansion of licensed, C-type lectin-like activating receptor Ly49H+ NK cells with increased IFNγ production after infection in nondepleted mice post-HSCT and after Treg depletion. Adoptive transfer of licensed NK subsets into immunodeficient hosts provided significantly greater MCMV resistance compared with transfer of total NK populations or unlicensed subsets. In non-HSCT mice, only concurrent depletion of Tregs or TGF-β neutralization resulted in detection of NK licensing effects. This suggests that licensed NK cells are the initial and rapidly responding population of NK cells to MCMV infection, but are highly regulated by Tregs and TGF-β.


Blood | 2013

Murine NK-cell licensing is reflective of donor MHC-I following allogeneic hematopoietic stem cell transplantation in murine cytomegalovirus responses

Can M. Sungur; Yajarayma J. Tang-Feldman; Anthony E. Zamora; Maite Alvarez; Claire Pomeroy; William J. Murphy

Natural killer (NK) cells express inhibitory receptors with varied binding affinities to specific major histocompatibility complex class I (MHC-I) haplotypes. NK cells can be classified as licensed or unlicensed based on their ability or inability to bind MHC-I, respectively. The role of donor vs host MHC on their development after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is not known. Following reciprocal MHC-disparate allogeneic transplants and during de novo NK-cell recovery, depletion of the licensed and not unlicensed population of NK cells as determined by the licensing patterns of donor MHC-I haplotypes, resulted in significantly increased susceptibility to murine cytomegalovirus (MCMV) infection. A corresponding expansion of the licensed Ly49H(+) NK cells occurred with greater interferon γ production by these cells than unlicensed NK cells in the context of donor MHC-I. Thus, NK licensing behavior to MCMV corresponds to the donor, and not recipient, MHC haplotype after allo-HSCT in mice.


Cardiovascular Pathology | 2010

In vivo characterization of cytokine profiles and viral load during murine cytomegalovirus-induced acute myocarditis

Jethro Trees Ritter; Yajarayma J. Tang-Feldman; G. Raymond Lochhead; Marko Estrada; Stephanie R. Lochhead; Cindy Yu; Amanda Ashton-Sager; Dipika Tuteja; Christian M. Leutenegger; Claire Pomeroy

BACKGROUND Murine cytomegalovirus (MCMV) is an etiologic agent of acute and chronic myocarditis in BALB/c mice. Immunologic host responses appear to play a key role in pathogenesis but have been incompletely defined. METHODS BALB/c mice were infected with a sublethal dose of MCMV. Cytokine transcription and viral load (measured by quantitative real-time polymerase chain reaction) and histopathological analyses were performed at specified time points. RESULTS Increased tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and interferon (IFN)-gamma, as well as IL-10 mRNA transcripts, were detected in the hearts of infected mice starting at Day 1 post-infection (p.i.), with peak levels occurring at Day 8 p.i. (7-fold, 14-fold, 41-fold, and 16-fold higher than background, respectively). Peak cytokine transcription significantly correlated with a 10-fold increase in viral load (P<.001) at Day 8 p.i. Myocarditis-related pathological changes, measured by infiltration foci, were greatest at Day 8 p.i., corresponding with peak cytokine transcription and significantly correlated with IFN-gamma levels (P<.0001). Infiltration foci were predominantly composed of CD3(+) T cells. Cardiac calcification was observed in most infected mice predominantly over the right ventricle. Histological analysis of heart sections from mice infected with recombinant enhanced green fluorescence protein-MCMV revealed a localized and sporadic pattern of virus throughout all heart layers. CONCLUSIONS MCMV-induced myocarditis in BALB/c mice is characterized by in vivo production of proinflammatory cytokines in a pattern correlating with MCMV viral load. The infection pattern and inflammatory response is highly localized, sporadic, and involves endocardium, epicardium, as well as the myocardium, with greatest amounts of virus detected in areas of pathologic calcification.


Diagnostic Microbiology and Infectious Disease | 2002

Clindamycin resistant strains of Clostridium difficile isolated from cases of C. difficile associated diarrhea (CDAD) in a hospital in Sweden

Torbjorn Norén; Yajarayma J. Tang-Feldman; Stuart H. Cohen; Joseph Silva; Per Olcén

Fifty three strains of C. difficile recovered from the stools of 13 patients with clinical C. difficile associated diarrhea (CDAD) were analyzed for the presence of the ermB gene, for toxigenicity and fingerprinting profile by PCR based assays. Forty five percent of the isolates were resistant to clindamycin and positive for the ermB gene. All clindamycin resistant isolates were ermB positive and belonged to the same fingerprinting group, suggesting clonal spread. These preliminary results suggest that clindamycin resistant isolates may be common etiologic agents of CDAD in Sweden.


Journal of Cardiovascular Translational Research | 2013

Murine Cytomegalovirus (MCMV) Infection Upregulates P38 MAP kinase in Aortas of Apo E KO Mice: a Molecular Mechanism for MCMV-Induced Acceleration of Atherosclerosis

Yajarayma J. Tang-Feldman; Stephanie R. Lochhead; G. Raymond Lochhead; Cindy Yu; Michael D. George; Amparo C. Villablanca; Claire Pomeroy

Multiple studies suggest an association between cytomegalovirus (CMV) infection and atherogenesis; however, the molecular mechanisms by which viral infection might exacerbate atherosclerosis are not well understood. Aortas of MCMV-infected and uninfected Apo E knockout (KO) mice were analyzed for atherosclerotic lesion development and differential gene expression. Lesions in the infected mice were larger and showed more advanced disease compared to the uninfected mice. Sixty percent of the genes in the MAPK pathway were upregulated in the infected mice. p38 and ERK 1/2 MAPK genes were 5.6- and 2.0-fold higher, respectively, in aortas of infected vs. uninfected mice. Levels of VCAM-1, ICAM-1, and MCP-1 were ~2.0–2.6-fold higher in aortas of infected vs. uninfected mice. Inhibition of p38 with SB203580 resulted in lower levels of pro-atherogenic molecules and MCMV viral load in aortas of infected mice. MCMV-induced upregulation of p38 may drive the virus-induced acceleration of atherogenesis observed in our model.


Infection Control and Hospital Epidemiology | 2005

SPATIAL AND TEMPORAL ANALYSIS OF CLOSTRIDIUM DIFFICILE INFECTION IN PATIENTS AT A PEDIATRIC HOSPITAL IN CALIFORNIA

Carmen E. Rexach; Yajarayma J. Tang-Feldman; Stuart H. Cohen

OBJECTIVE To examine the usefulness of temporal and spatial analysis in identifying nosocomial transmission of Clostridium difficile among pediatric patients hospitalized on four wards at The Childrens Hospital of Central California from September 8, 1998, to January 16, 1999. DESIGN Stool specimens obtained from the clinical microbiology laboratory during the study period were tested by culture and latex agglutination for C. difficile. Polymerase chain reaction was used to identify toxin genes. Isolates obtained were mapped to a grid for each ward and were analyzed using the Knox test. Results were compared with DNA fingerprints generated by arbitrarily primed polymerase chain reaction. RESULTS Total occupancy of these 4 wards was 438 during the study period. Stool specimens were available for 256 (58%) of these patients, yielding 67 C. difficile isolates and generating 2,211 case pairs for analysis by the Knox test. After stratification by toxin status, 5 clustered pairs of toxigenic isolates were identified on 1 of the wards by this method. Fingerprint analysis identified 4 clusters with indistinguishable banding patterns on 2 of the 4 wards. Two of the identified clusters were toxigenic and 2 were nontoxigenic. None of these clusters corresponded to clusters identified by the Knox test. CONCLUSIONS The Knox test is an ineffective method for identifying cases resulting from nosocomial transmission of C. difficile in a pediatric setting due to the persistence of C. difficile spores and the unique environment of a pediatric hospital. Molecular analysis remains the most effective method.


Clinical Infectious Diseases | 2005

Prevalence of the ermB Gene in Clostridium difficile Strains Isolated at a University Teaching Hospital from 1987 through 1998

Yajarayma J. Tang-Feldman; Jeffrey P. Henderson; Grit Ackermann; Stephanie S. Feldman; Maxwell Bedley; Joseph Silva; Stuart H. Cohen

We analyzed 226 strains of Clostridium difficile for the presence of erythromycin ribosomal methylase B (ermB) genes. Forty-four strains (19.4%) carried ermB genes and were resistant to erythromycin. Toxin A and toxin B gene sequences were identified in 81.9% of these 44 strains. Strains of C. difficile that carry ermB genes are common etiologic agents of C. difficile-associated diarrhea.


JMIR Research Protocols | 2018

mHealth Technology and Nurse Health Coaching to Improve Health in Diabetes: Protocol for a Randomized Controlled Trial

Sheridan Miyamoto; Madan Dharmar; Sarina Fazio; Yajarayma J. Tang-Feldman; Heather M. Young

Background Chronic diseases, including diabetes mellitus, are the leading cause of mortality and disability in the United States. Current solutions focus primarily on diagnosis and pharmacological treatment, yet there is increasing evidence that patient-centered models of care are more successful in improving and addressing chronic disease outcomes. Objective The objective of this clinical trial is to evaluate the impact of a mobile health (mHealth) enabled nurse health coaching intervention on self-efficacy among adults with type-2 diabetes mellitus. Methods A randomized controlled trial was conducted at an academic health system in Northern California. A total of 300 participants with type-2 diabetes were scheduled to be enrolled through three primary care clinics. Participants were randomized to either usual care or intervention. All participants received training on use of the health system patient portal. Participants in the intervention arm received six scheduled health-coaching telephone calls with a registered nurse and were provided with an activity tracker and mobile application that integrated data into the electronic health record (EHR) to track their daily activity and health behavior decisions. All participants completed a baseline survey and follow-up surveys at 3 and 9 months. Primary and secondary outcomes include diabetes self-efficacy, hemoglobin A1c (HbA1c), and quality of life measures. Results Data collection for this trial, funded by the Patient-Centered Outcomes Research Institute, will be completed by December 2017. Results from the trial will be available mid-2018. Conclusions This protocol details a patient-centered intervention using nurse health coaching, mHealth technologies, and integration of patient-generated data into the EHR. The aim of the intervention is to enhance self-efficacy and health outcomes by providing participants with a mechanism to track daily activity by offering coaching support to set reasonable and attainable health goals, and by creating a complete feedback loop by bringing patient-generated data into the EHR. Trial Registration ClinicalTrials.gov NCT02672176; https://clinicaltrials.gov/ct2/show/NCT02672176 (Archived by WebCite at http://www.webcitation.org/6xEQXe1M5)


Antiviral Therapy | 2011

Paradoxical response to prophylactic Didox (N-3, 4 trihydroxybenzamide) treatment in murine cytomegalovirus-infected mice.

Vera Go; Yajarayma J. Tang-Feldman; Stephanie R. Lochhead; G. Raymond Lochhead; Cindy Yu; Howard L. Elford; Mohammed S. Inayat; Oliver R. Oakley; Claire Pomeroy

BACKGROUND In this study, we investigated the effect of Didox (DX) on the pathogenicity of and host responses to murine cytomegalovirus (MCMV) infection. METHODS In vitro efficacy of DX against MCMV was determined using plaque reduction assays. For in vivo studies, mice infected with a sublethal dose (10(4) PFU) of MCMV were treated daily with DX (200 mg/kg) using either a prophylactic or delayed protocol. At predetermined intervals, target organs were removed for histopathology. Cytokine transcription and viral load were performed using real-time PCR. Serum cytokine levels were determined by ELISA, and T-cell markers by real-time PCR. RESULTS DX (0.5-50 μM) inhibited MCMV plaque formation in vitro. However, in vivo, prophylactic DX treatment did not decrease viral load and prolonged hepatic proinflammatory cytokine transcription at days 3 and 5 post-infection, which corresponded with more severe histopathological changes observed in the liver. Significant CD8(+) T-cell marker suppression was seen, in accordance with DX-induced inhibition of lymphocyte proliferation observed in vitro. DX prolonged the recovery of MCMV-infected mice when given after infection was established. CONCLUSIONS Despite promising MCMV inhibition in vitro, DX had no beneficial effect on MCMV disease in our model and paradoxically had adverse effects when administered prophylactically. The lack of correlation between in vitro activity and in vivo efficacy emphasizes the importance of selecting appropriate antiviral targets and of using animal models when testing new drugs.

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Claire Pomeroy

University of California

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Cindy Yu

University of California

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Can M. Sungur

University of California

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Joseph Silva

University of California

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