Ramesh Kumar Wali

Publications (81) View all

• Article: Early withdrawal of calcineurin inhibitors and rescue immunosuppression with sirolimus-based therapy in renal transplant recipients with moderate to severe renal dysfunction.

  R K Wali, V Mohanlal, E Ramos, S Blahut, C Drachenberg, J Papadimitriou, M Dinits, A Joshi, B Philosophe, C Foster, C Cangro, J Nogueira, M Cooper, S T Bartlett, M R Weir
  [show abstract] [hide abstract]
  ABSTRACT: Mammalian Target-of-Rapamycin inhibitors (mTOR inhibitors) can be used to replace the calcineurin inhibitors (CNIs) to prevent progression in chronic kidney disease (CKD) following organ transplantation. Discontinuation of tacrolimus in 136 recipients of kidney transplants with progressive renal dysfunction significantly decreased the rate of loss of estimated glomerular filtration rate (eGFR, mL/min/1.73 m(2)) (pre-intervention vs. post-intervention slopes, -0.013 vs. -0.002, p < 0.0001). Discontinuation of tacrolimus was associated with a sustained and significant improvement in graft function (pre-eGFR vs. post-eGFR; 26.0 +/- 1.1 vs. 47.4 +/- 2.1, p < 0.0001) in 74% of patients. This intervention was ineffective if the mean and (median) values of creatinine (mg/dL) and eGFR were 3.8 +/- 0.2 (3.4) and 18.4 +/- 1.9 (22.4), respectively, at the time of conversion therapy. During the follow-up (range, 1.5-34.6, months), a total of 13 patients had their first acute rejection following the conversion therapy, an annual incidence of less than 10% and none of these episodes resulted in graft loss. The salutary effects of sirolimus therapy following discontinuation of tacrolimus in patients with moderate to severe graft dysfunction due to allograft nephropathy even in high-risk patients improves kidney function and prevents acute rejection.
  American Journal of Transplantation 06/2007; 7(6):1572-83. · 6.39 Impact Factor
• Article: Increased microvascular blood content is an early event in colon carcinogenesis.

  R K Wali, H K Roy, Y L Kim, Y Liu, J L Koetsier, D P Kunte, M J Goldberg, V Turzhitsky, V Backman
  [show abstract] [hide abstract]
  ABSTRACT: Increased premalignant epithelial microvascular blood content is a common theme in neoplastic transformation; however, demonstration of this phenomenon in colon carcinogenesis has been stymied by methodological limitations. Our group has recently developed a novel optics technology, four dimensional elastic light scattering fingerprinting (4D-ELF), which allows examination of the colonic mucosal architecture with unprecedented accuracy. In this study, we utilised 4D-ELF to probe the preneoplastic colonic microvasculature. Colonic mucosal blood content was assessed by 4D-ELF at serial preneoplastic time points from azoxymethane (AOM) treated Fisher 344 rats and age matched control animals. We also examined the pretumorigenic intestinal mucosa of the MIN mouse, and compared with wild-type mice. Finally, in a pilot study, we examined superficial blood content from the endoscopically normal mid transverse colon in 37 patients undergoing screening colonoscopy. In the AOM treated rat model, augmentation of superficial mucosal and total mucosal/superficial submucosal blood supply preceded the appearance of aberrant crypt foci (ACF) and temporally and spatially correlated with future ACF occurrence. These findings were replicated in MIN mice. The 4D-ELF based results were corroborated with immunoblot analysis for haemoglobin on mucosal scrapings from AOM treated rats. Moreover, 4D-ELF analysis of normal human colonic mucosa indicated that there was a threefold increase in superficial blood in patients who harboured advanced adenomas. We report, for the first time, that blood content is increased in the colonic microvasculature at the earliest stages of colon carcinogenesis. These findings may provide novel insights into early biological events in colorectal carcinogenesis and have potential applicability for screening.
  Gut 06/2005; 54(5):654-60. · 10.11 Impact Factor
• Conference Proceeding: Light scattering fingerprints of initial pre-dysplastic events in colon carcinogenesis

  Y.L. Kim, Y. Liu, R.K. Wali, H.K. Roy, M.J. Goldberg, A.K. Kromine, K. Chen, V. Backman
  [show abstract] [hide abstract]
  ABSTRACT: We report detection of slight alterations of tissue micro-architecture by recording multidimensional data characterizing tissue light scattering. In the animal studies, we show that these light scattering "fingerprints" change dramatically even in the earliest pre-dysplastic stages of carcinogenesis, much earlier than currently known histological, molecular, or genetic markers.
  Engineering in Medicine and Biology Society, 2003. Proceedings of the 25th Annual International Conference of the IEEE; 10/2003
• Conference Proceeding: Simultaneous measurement of angular and spectral properties of light scattering for early cancer detection

  Yang Liu, Y L Kim, R K Wali, H K Roy, M.J. Goldberg, A.K. Kromine, Kun Chen, V Backman
  [show abstract] [hide abstract]
  ABSTRACT: A novel instrument has been developed for the angular, spectral, azimuthal and polarization measurements of the light backscattering by living biological tissues. These measurements provide the most comprehensive quantitative information about the light scattering and allow obtaining unique quantitative information about the microarchitecture of living cells and tissues. We have shown the potential of this technique to characterize and diagnose very early premalignant changes in the epithelia, for which no histological or molecular markers has yet been established. Using this technique in our studies with a rodent model of colon carcinogenesis we obtained several parameters diagnostically significant for the detection of precancerous changes, such as the number density of red blood cells in the capillary network immediately underlying the epithelium, the fractal dimension of the tissue microarchitecture, and the average roundness of subcellular structures.
  Lasers and Electro-Optics, 2003. CLEO '03. Conference on; 07/2003
• Source

  Available from: arizona.edu

  Article: Simultaneous measurement of angular and spectral properties of light scattering for characterization of tissue microarchitecture and its alteration in early precancer

  Y.L. Kim, Yang Liu, R.K. Wali, H.K. Roy, M.J. Goldberg, A.K. Kromin, Kun Chen, V. Backman
  [show abstract] [hide abstract]
  ABSTRACT: We present a novel instrument to measure the spectral, angular, azimuthal, and polarization dependence of light backscattered by living biological tissues, thus providing the most comprehensive description of the light scattering to obtain unique quantitative information about the microarchitecture of living cells and tissues. We show the potential of this technique to characterize and diagnose early premalignant changes in the epithelia. In studies with a rodent model of colon carcinogenesis, we show that several parameters obtained using this technique, such as the number density of red blood cells in the capillary network immediately underlying the epithelium, the fractal dimension of the tissue, and the average roundness of subcellular structures, are significant for detection of precancerous changes at a very early stage of the carcinogenic process, at which no other histological or molecular markers have been identified.
  IEEE Journal of Selected Topics in Quantum Electronics 04/2003; · 3.78 Impact Factor