Evolution of pre-treatment stenting and local anesthesia for extracorporeal shock wave lithotripsy at a single university center

Evolution of the extracorporeal shock wave lithotripsy technique involves not just second generation technology but operator innovations and experience. Retrospective analysis of the first 512 treatments at a university medical stone unit using the Dornier HM3 lithotriptor was compared to 3 intervals of 100 consecutive treatments during the next 2-year period (1985 to 1987). Patient referral and selection as well as treatment techniques and rates of endourological interventions were analyzed. Patient demographics, stone types and retreatment rates remained constant during 2,500 treatments. However, the use of local anesthesia and internal ureteral stents became increasingly common. Of the 1987 cohort 29% were treated with the patient under local anesthesia, and 23 of the 44 with a stent (52%) received internal ureteral stents. Other treatment trends identified during the study period included increasing number of large (greater than 2 cm.) and multiple stones treated; increasing use of internal and external ureteral catheters before treatment, fewer stents for small, mobile renal calculi and decreasing length of hospital stay (2.7 to 2.1 days) with increasing use of stents before lithotripsy. The increasing average number of shock waves per treatment (1,382 versus 1,580) during the study period can be attributed to the larger proportion of patients with high stone burdens and the impact of an increased number of operators with more varied criteria for endoscopy and treatment end point.     

IGF-I receptors in the bovine neural retina: structure, kinase activity and comparison with retinal insulin receptors

The retina contains specific high-affinity receptors for insulin-like growth factor-I (IGF-I). Although IGF-I binding was observed in photoreceptor outer segments, the level of this binding was only 10% of that found in whole retina or mixed preparations of rod outer (ROS) and inner (RIS) segments. The higher IGF-I binding activity in RIS and non-photoreceptor regions of the retina suggests these sites as candidates for putative IGF-I action. Data from crosslinking experiments with and without neuraminidase treatment indicate that the binding subunits of the retinal IGF-I receptor exist in two subpopulations (Mr = 121- and 131 kDa), and that the larger of the two subunits has either a greater number or more exposed sialic acid residues. In these characteristics, the retinal IGF-I receptor is similar to the retinal insulin receptor. Retinal IGF-I and insulin receptors possess kinase activity towards their own beta-subunits, a tyrosine containing copolymer, and various molecular forms and subunits of transducin (T alpha-GDP, T alpha-GTP, T beta). The transducin forms are phosphorylated with different efficiencies (e.g. T alpha-GDP is 10-15 times more effective than T alpha-GTP as substrate). These differences are also observed in basal conditions and may reflect differences in transducin subunit affinity for the IGF-I and insulin receptor. In all retinal areas examined, tracer IGF-I binding is 10 to 20-fold higher than insulin binding; however, autophosphorylation levels are approximately equal.     

Bone death in transient regional osteoporosis.

A 48-year-old man developed transient regional osteoporosis, with hip and later knee pain. He responded well to lumbar sympathectomy. The femur and tibia adjacent to the painful knee were osteoporotic, while the medial femoral condyle showed increased uptake in a bone scan. In the femoral condyle, bone histology showed areas of dead bone undergoing osteoclastic resorption, and increased bone formation. The tibial bone was histologically normal. The partial bone death in the distal femur suggests that the disorder may be related to both avascular necrosis of bone and reflex sympathetic dystrophy.     

Mutation analysis of feline Niemann-Pick C1 disease

Niemann-Pick C (NPC) disease is an autosomal recessive neurovisceral lysosomal storage disorder that results in defective intracellular transport of cholesterol. The major form of human NPC (NPC1) has been mapped to chromosome 18, the NPC1 gene (NPC1) has been sequenced and several mutations have been identified in NPC1 patients. A feline model of NPC has been characterized and is phenotypically, morphologically, and biochemically similar to human NPC1. Complementation studies using cultured fibroblasts from NPC affected cats and NPC1 affected humans support that the gene responsible for the NPC phenotype in this colony of cats is orthologous to human NPC1. Using human-based PCR primers, initial fragments of the feline NPC cDNA were amplified and sequenced. From these sequences, feline-specific PCR primers were generated and designed to amplify six overlapping bands that span the entire feline NPC1 open reading frame. A single base substitution (2864G-C) was identified in NPC1 affected cats. Obligate carriers are heterozygous at the same allele and a PCR-based assay was developed to identify the geneotype of all cats in the colony. The mutation results in an amino acid change from cysteine to serine (C955S). Several of the mutations identified in people occur in the same region. Marked similarity exists between the human and feline NPC1 cDNA sequences, and is greater than that between the human and murine NPC1 sequences. The human cDNA sequence predicts a 1278aa protein with a lysosomal targeting sequence, several trans-membrane domains and extensive homology with other known mediators of cholesterol homeostasis.     

The nitric oxide pathway in pre-eclampsia: pathophysiological implications

Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with N^G-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined.     

Surgical sperm retrieval and intracytoplasmic sperm injection as treatment of obstructive azoospermia

Male genital tract obstructions may result from infections, previous inguinal and scrotal surgery (vasectomy) and congenital bilateral absence of the vas deferens (CBAVD). Microsurgery can sometimes be successful in treating the obstruction. In other cases and in cases of failed surgical intervention, the patient can be treated by microsurgical or percutaneous epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). We present the results of 39 ICSI procedures for obstructive azoospermia in 24 couples. The aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD in nine and genital infections in four. Sperm retrieval was accomplished via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was only applied when PESA failed to produce enough spermatozoa for simultaneous ICSI. In six patients, the ICSI procedure was performed with cryopreserved spermatozoa after an initial PESA procedure. Fertilization occurred in 47% of the metaphase II oocytes; embryo transfer was performed in 92% of procedures and resulted in a clinical pregnancy in 13/39 procedures. Ongoing pregnancy was achieved in 10/39 procedures. One pregnancy was terminated early after prenatal investigation showed a cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine pregnancies resulted in the live birth of 10 children, without any congenital abnormalities. Epididymal and testicular retrieved spermatozoa were successfully used for ICSI to treat obstructive azoospermia, and resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI procedures, a success rate of 25.6% per treatment cycle and of 27.7% per embryo transfer.