Identification and validation of genes involved in the pathogenesis of colorectal cancer using cDNA microarrays and RNA interference.

PURPOSE: The purpose of this study was to profile gene expression changes in colorectal tumors to identify new targets and strategies for the management of this disease. EXPERIMENTAL DESIGN: cDNA microarray analysis was used to detect differences in gene expression between normal tissue and colon tumors and polyps isolated from 20 patients. To identify genes that are important in regulating the growth properties of colorectal cancer, RNA interference (RNAi) was used to disrupt expression of several of the overexpressed genes in a colon tumor cell line, HCT116, which showed similar patterns of gene expression as many of the patient tumors. RESULTS: Expression changes of > or =2-fold in approximately one-third of the patients were consistently observed for 2632 of a total of 9592 genes (574 up-regulated genes and 2058 down-regulated genes). Subsequent analysis of 13 genes by quantitative real-time PCR confirmed the reliability of this analysis. RNAi-mediated disruption of the expression of one of these genes, survivin, a potent inhibitor of apoptosis, severely reduced tumor growth both in vitro and in an in vivo xenograft model. CONCLUSIONS: The combined use of microarray analysis and RNAi provides an excellent system to define the role of specific genes that are up-regulated in cancer lead to the increased in vitro and in vivo growth of colon tumors.     

Expanding the living related donor pool in renal transplantation: use of marginal donors

PURPOSE: In a living related transplantation program it is not always possible to find an ideal donor. Sometimes the only available donor in the family has some benign disease or suboptimal renal anatomy or physiology, or is too old to be accepted and defined as a marginal donor. However, with proper screening the donor pool can be increased by accepting these marginal donors and treating the benign diseases which is beneficial to the donor. We evaluate the outcome of grafts from marginal donors. MATERIALS AND METHODS: From July 1988 to August 1997, 581 live related transplantations were performed. Of the donors 52 were older than 60 years and 34 had associated benign renal or nonrenal anomaly or disease. These donors were accepted after thorough questioning and consultation with family members. The recipients of graft from elderly donors were evaluated for the number of rejections, serum creatinine at last followup and graft survival. RESULTS: Of the recipients 52 received grafts from elderly donors with a mean age of 62.6+/-3.7 years. Mean followup was 34.14+/-0.7 months. The 2 and 5-year actuarial graft survival was 96% and 74%, respectively. Creatinine was normal (less than 1.5) in 37% of recipients and 1.5 to 2.5 mg.% in 46%. The rejection rate in postoperative month 1 was 29%. All donors underwent simultaneous surgery to treat the benign disease, and all did well after surgery. CONCLUSIONS: By accepting these marginal donors a 14.6% increase in the living related donor pool was achieved without compromising recipient or donor safety. Otherwise these recipients would have been forced to undergo unrelated transplantation or be maintained on dialysis, which is particularly difficult in a developing country. Donors with associated disease benefited from cure.     

Tetrahydrobiopterin improves endothelial function in human saphenous veins

OBJECTIVES: Diminished production of nitric oxide has been linked to saphenous vein endothelial dysfunction. Tetrahydrobiopterin is an obligate cofactor for the oxidation of L -arginine by nitric oxide synthase in the production of nitric oxide by endothelial cells. The objective of the present study was to examine whether the exogenous addition of tetrahydrobiopterin improves endothelial function in saphenous veins from patients undergoing coronary artery bypass graft operations. METHODS: Vascular segments of saphenous veins were obtained from 17 patients undergoing elective coronary artery bypass grafting, and in vitro endothelium-dependent and endothelium-independent responses to acetylcholine and sodium nitroprusside were assessed. Isometric dose-response curves were constructed in precontracted rings in the presence and absence of tetrahydrobiopterin (0.1 mmol/L) with the use of the organ bath apparatus. The percentages of maximum relaxation and sensitivity were compared between interventions. RESULTS: Acetylcholine caused dose-dependent endothelium-mediated relaxation in saphenous veins. In the presence of tetrahydrobiopterin, acetylcholine-induced relaxation was significantly augmented (percentage maximum relaxation, 16.8% +/- 2.9% vs control 7.5% +/- 1.8%; P =.003) without an effect on agonist sensitivity. These effects were endothelium-specific because endothelium-independent responses to sodium nitroprusside were preserved. CONCLUSIONS: These data uncover beneficial effects of acute tetrahydrobiopterin addition on endothelial function in human vessels. Because endothelial dysfunction has been implicated in the development of graft failure, studies aimed at chronic delivery of tetrahydrobiopterin would be useful in determining the contribution of this cofactor toward saphenous vein atherosclerosis.     

Development and evaluation of osmotically controlled oral drug delivery system of glipizide.

Extended release formulation of glipizide based on osmotic technology was developed and evaluated. The effect of different formulation variables, namely, level of solubility modifier in the core, membrane weight gain, and level of pore former in the membrane, were studied. Drug release was found to be affected by the level of solubility modifier in the core formulation. Glipizide release was inversely proportional to the membrane weight but directly related to the initial level of pore former (PVP) in the membrane. Burst strength of the exhausted shells increased with the weight gain of the membrane. On the other hand, burst strength decreased with an increase in the level of pore former in the membrane. Drug release from the developed formulations was independent of pH and agitational intensity, but dependent on the osmotic pressure of the release media. Results of SEM studies showed the formation of pores in the membrane from where the drug release occurred. The numbers of pores were directly proportional to the initial level of pore former in the membrane. The manufacturing procedure was found to be reproducible and formulations were stable after 3 months of accelerated stability studies.     

Analysis of COVID-19-associated rhino-orbital-cerebral mucormycosis patients in a tertiary care center in Northern India

Purpose:An unprecedented surge has been noted in rhino-orbital-Cerebral mucormycosis (ROCM) in times of current COVID-19 pandemic. The present prospective study aims to evaluate clinico-epidemiological profile, risk factors, management, and outcome of the cases of ROCM that presented to our tertiary care center during the study period from April to June 2021.Methods:All patients were subjected to complete history taking, ophthalmological examination, and imaging studies. The patients were staged and were treated with intravenous liposomal amphotericin B (AMB) and sino-nasal debridement of local necrotic tissue. Transcutaneous retrobulbar AMB (TRAMB), orbital decompression, and exenteration were instituted as indicated. All patients were followed up for a minimum of 6 months before arriving at the final outcome. Statistical analysis was performed.Results:A total of 49 patients presented during the study period, with a mean age of 42.2 years. The major risk factors included uncontrolled diabetes (89.8%), COVID-19 positivity (51.02%), and concurrent steroid use (38.77%). The most common presenting symptom was facial pain/swelling (43.65%), while the most common presenting sign was deterioration in vision (75.51%). Intravenous liposomal AMB was given to all patients along with sino-nasal debridement (85.71%), TRAMB (57.14%), orbital decompression (14.28%), and exenteration (12.24%). Overall, mortality at 6 months was 22.45% (11 patients). Age more than 60 years, intracranial extension, and HbA1c of more than 8.0% were observed to be statistically significant indicators of mortality.Conclusion:Early suspicion and timely diagnosis of mucormycosis at rhino-orbital stage is warranted in order to salvage life as well as visual function. TRAMB may prove as potentially favorable treatment modality in cases with limited orbital involvement.     

Connectomic assessment of injury burden and longitudinal structural network alterations in moderate‐to‐severe traumatic brain injury

Traumatic brain injury (TBI) is a major public health problem. Caused by external mechanical forces, a major characteristic of TBI is the shearing of axons across the white matter, which causes structural connectivity disruptions between brain regions. This diffuse injury leads to cognitive deficits, frequently requiring rehabilitation. Heterogeneity is another characteristic of TBI as severity and cognitive sequelae of the disease have a wide variation across patients, posing a big challenge for treatment. Thus, measures assessing network‐wide structural connectivity disruptions in TBI are necessary to quantify injury burden of individuals, which would help in achieving personalized treatment, patient monitoring, and rehabilitation planning. Despite TBI being a disconnectivity syndrome, connectomic assessment of structural disconnectivity has been relatively limited. In this study, we propose a novel connectomic measure that we call network normality score (NNS) to capture the integrity of structural connectivity in TBI patients by leveraging two major characteristics of the disease: diffuseness of axonal injury and heterogeneity of the disease. Over a longitudinal cohort of moderate‐to‐severe TBI patients, we demonstrate that structural network topology of patients is more heterogeneous and significantly different than that of healthy controls at 3 months postinjury, where dissimilarity further increases up to 12 months. We also show that NNS captures injury burden as quantified by posttraumatic amnesia and that alterations in the structural brain network is not related to cognitive recovery. Finally, we compare NNS to major graph theory measures used in TBI literature and demonstrate the superiority of NNS in characterizing the disease.     

In vitro antiprotozoal activity of some xanthones isolated from the roots of Andrographis paniculata

Four xanthones isolated from the roots of Andrographis paniculata were tested in vitro for antiprotozoal activity against Trypanosoma brucei brucei, Trypanosoma cruzi and Leishmania infantum. Compound TDR13011 (1,2-dihydroxy-6,8-dimethoxy-xanthone) showed good activity against T. b. brucei and L. infantum with a 50% inhibitory concentration (IC50) of 4.6 microg/ml and 8 microg/ml respectively. Xanthones from the roots of Andrographis paniculata exhibited promising anti-protozoal activity and these compounds could be chemically modified to obtain a more potent product.