Extra Hilar Branching of Renal Arteries: An Anatomical Study.

Introduction: The objective of this study was to observe the patterns of different arteries that supply the kidneys. The kidney has a segmental distribution of arteries. The kidneys are divided into five vascular segments. The arteries that arise from the aorta above or below the main renal artery and reach the hilum are called accessory renal arteries. They are persistent embryonic lateral splanchnic arteries. Accessory renal arteries may arise from the celiac or superior mesenteric arteries, near the bifurcation or from the common iliac arteries. The present study has attempted to find out accessory, and aberrant arteries to kidneys with review of literature. Materials and Methods: The study was done on 52 kidneys randomly selected from cadavers that were used for the purpose of teaching in the department of Anatomy at P.E.S Medical College. The kidneys were removed from the cadavers en-block with the arteries and veins intact. The renal artery was observed for its pattern of branching. Observations and Discussion: The pre-hilar branching pattern was absent only in six kidneys out of the 52 kidneys selected. The branches given before entering the hilum were either in the form of a fork pattern or a ladder pattern in the remaining 46 kidneys. The fork pattern wherein the branches arose from a single point was found in 42 kidneys. The ladder patterns were seen in two posterior segment arteries and two anterior segment arteries. The anterior division often showed the fork patterns which were either duplicate or triplicate outside the hilum more proximally, with further division into duplicate or triplicate terminal branches closer to the hilum but significantly outside.

Effect of intermittent hypobaric hypoxia on efficacy & clearance of drugs.

Background & objectives: People travelling to high altitude for occupational, recreational or religious purposes are mostly healthy and fit but sometimes they use drugs for common ailments like influenza, acute mountain sickness or chronic disease like diabetes. Limitation of oxygen at high altitude may compromise metabolism of drugs. Hence, we undertook this study to assess the effect of hypobaric hypoxia on some commonly used drugs in rats and rabbits. Methods: Effect of intermittent hypobaric hypoxia on phenotypic expression of anesthetic drugs pentabarbitone, thiopentone and zoxazolamine (sleeping time) was assessed in rats exposed to 282.4 mm Hg equivalent to 25000 feet in a decompression chamber. Plasma clearance of some commonly used drugs was investigated in rabbits exposed to 429 mm Hg equivalent to 15000 feet. Pharmacokinetic parameters were computed by plotting drug concentration versus time curve on semi log scale. Results: A significant delay in regaining rightening reflex was observed in rats exposed to intermittent hypobaric hypoxia in response to zoxazolamine, pentobarbitone and thiopentone sodium. Pharmacokinetics of acetyl salicylic acid, gentamicin, phenobarbitone and acetazolamide showed increase in plasma half life (t1/2), decrease in elimination rate constant (kel) and hence prolonged residence of these drugs in hypoxic animals. Interpretation & conclusions: This experimental study showed that hypoxia altered therapeutic effectiveness and clearance of several drugs, in rats and rabbits exposed to intermittent hypobaric hypoxia. s0 uch studies need to be done in human volunteers to see the effect of hypoxia on pharmacokinetics of some common drugs.

Non invasive real-time monitoring of bacterial infection & therapeutic effect of anti-microbials in five mouse models.

Background & objectives: In vivo imaging system has contributed significantly to the understanding of bacterial infection and efficacy of drugs in animal model. We report five rapid, reproducible, and non invasive murine pulmonary infection, skin and soft tissue infection, sepsis, and meningitis models using Xenogen bioluminescent strains and specialized in vivo imaging system (IVIS). Methods: The progression of bacterial infection in different target organs was evaluated by the photon intensity and target organ bacterial counts. Genetically engineered bioluminescent bacterial strains viz. Staphylococcus aureus Xen 8.1, 29 and 31; Streptococcus pneumoniae Xen 9 and 10 and Pseudomonas aeruginosa Xen-5 were used to induce different target organs infection and were validated with commercially available antibiotics. Results: The lower limit of detection of colony forming unit (cfu) was 1.7-log10 whereas the lower limit of detection of relative light unit (RLU) was 4.2-log10. Recovery of live bacteria from different target organs showed that the bioluminescent signal correlated to the live bacterial count. Interpretation & conclusions: This study demonstrated the real time monitoring and non-invasive analysis of progression of infection and pharmacological efficacy of drugs. These models may be useful for pre-clinical discovery of new antibiotics.