Allopurinol Reduces the Lethality Associated with Acute Renal Failure Induced by Crotalus durissus terrificus Snake Venom: Comparison with Probenecid

In Brazil, among registered snake bites, those by the genus Crotalus originate the highest mortality rate. The rattlesnake Crotalus durissus terrificus is the most frequently implicated in these accidents. The kidney is a particularly vulnerable organ to the venom of this rattlesnake. In fact, the most serious complication of Crotalus snake bite is the renal dysfunction, and among the fatal cases of Crotalus bites in Brazil 5% are patients treated with antivenom. The hyperuricemia has been observed in human accidents with snake venoms, but this parameter has not received any special attention as a relevant factor in the etiology of renal dysfunction caused by these venoms. This study examined the effects of treatments with low-cost and low-risk uricostatic (allopurinol) and uricosuric (probenecid) drugs on the envenomation by C. d. terrificus, showing that allopurinol and probenecid mitigated certain nephrotoxic effects, as well as the survival of envenomed mice was improved through the effects of allopurinol on reduction of oxidative stress and intracellular formation of uric acid. This new knowledge provides consistent evidences linking uric acid with the renal dysfunction induced by rattlesnake bites and that the allopurinol deserves to be clinically evaluated as an approach complementary to anti-snake venom serotherapy

Psyllium: a promising polymer for sustained release formulations in combination with HPMC polymers

Psyllium has a mucilaginous property that makes it a good candidate to be utilized as an excipient in the preparation of controlled release systems. Various formulations were prepared using theophylline as a model drug and investigated with a view to achieve an ideal slow drug release profile. The addition of hydroxypropyl methylcellulose (HPMC) to psyllium significantly reduced the burst release; however, the percentage of drug release within a 12 h period was too slow and thereby inadequate. This was overcome by the addition of lactose as a hydrophilic filler that enabled a slow release with roughly 80% drug release in 12 h. The inclusion of HPMC within psyllium formulations changed the drug release kinetics from Fickian diffusion to anomalous transport. Granulated formulations demonstrated slower drug release than ungranulated or physical mixture and caused a change in the dissolution kinetics from Fickian diffusion to anomalous transport. Milled granules showed more efficient controlled drug release with no burst release. Milling of the granules also changed the drug release kinetics to anomalous transport. Although psyllium was proved to be a promising polymer to control the drug release, a combination of psyllium-HPMC and formulation processes should be considered in an attempt to achieve a zero-order release

From 3D Building Information Modeling Towards 5D City Information Modeling

This paper gives an overview of digital methods currently used for three-dimensional modeling of urban structures as utilized in architecture and town planning. The paper presents new trends in the field of CIM (City Information Modeling), and points to the complexity of problems of planning as seen from the perspective of town planning, indicating the necessity to introduce and visualize the semantic context in 3D modeling at the urban structure level