Cre/loxP-mediated in vivo excision of large segments from yeast genome and their amplification based on the 2microm plasmid-derived system

The loss of spleen may lead to fatal bacterial infections. To prevent this, splenic autotransplantation has been performed in humans and experimental animals. However, there is still controversy about the protective function of this procedure. Since innervation plays an important role in splenic function, we investigated whether splenic regenerates are re-innervated, and whether this depends on the donor and host age. Splenic tissue (30 mg) was implanted into the greater omentum of either young (2 days) or old (12 months) rats, from either young or old syngeneic animals. After 3 months of regeneration, the weight of the regenerates was determined, PGP+ nerve fibers were revealed by immunohistology, and subdivided into nerve fibers of sympathetic (TH+, NPY+) or sensory (SP+, CGRP+) origin. In addition, proliferating (Ki-67 proliferation antigen+) and apoptotic cells (TUNEL technique+) were likewise investigated. No innervation of splenic regenerates was observed after implantation into old hosts, correlating with poorly developed splenic compartments. In contrast, almost normal re-innervation occurred in young hosts after implantation of both young and old splenic tissue. These regenerates showed well-developed splenic compartments and a normal number and tissue distribution of proliferating and apoptotic cells. However, after the implantation of young tissue, the final size of splenic regenerates was three times larger (140 +/- 30 vs. 40 +/- 10 mg). Thus, re-innervation of splenic implants is necessary for their subsequent development. It is determined by host age, whereas the final size of the splenic regenerates is regulated by donor age-dependent factors. This model is useful for studying both the process leading to initial innervation and the consequences of this innervation.     

Germline mutations of the BRCA1 and BRCA2 genes in a breast and ovarian cancer patient

Nitric oxide (NO) has been implicated as a modulator of the vascular effects of angiotensin II (ANG II) in the kidney. We used a NO-sensitive microelectrode to study the effect of ANG II on NO release, and to determine the effect of selective inhibition of the ANG II subtype I receptor (AT1) with losartan (LOS) and candesartan (CAN). NO release from isolated and perfused renal resistance arteries was measured with a porphyrin-electroplated, carbon fiber. The vessels were microdissected from isolated perfused rat kidneys and perfused at constant flow and pressure in vitro. The NO-electrode was placed inside the glass collection cannula to measure vessel effluent NO concentration. ANG II stimulated NO release in a dose-dependent fashion: 0.1 nM, 10 nM and 1000 nM ANG II increased NO-oxidation current by 85+/-18 pA (n = 11), 148+/-22 pA (n = 11), and 193+/-29 pA (n = 11), respectively. These currents correspond to changes in effluent NO concentration of 3.4+/-0.5 nM, 6.1+/-1.1 nM, and 8.2+/-1.3 nM, respectively. Neither LOS (1 muM) nor CAN (1 nM) significantly affected basal NO production, but both AT1-receptor blockers markedly blunted NO release in response to ANG II (10 nM): 77+/-6% inhibition with LOS (n = 8) and 63+/-9% with CAN (n = 8). These results are the first to demonstrate that ANG II stimulates NO release in isolated renal resistance arteries, and that ANG II-induced NO release is blunted by simultaneous AT1-receptor blockade. Our findings suggest that endothelium-dependent modulation of ANG II-induced vasoconstriction in renal resistance arteries is mediated, at least in part, by AT1-receptor-dependent NO release.     

Evidence for a frizzled-mediated wnt pathway required for zebrafish dorsal mesoderm formation

We have used zebrafish as a model system for the study of vertebrate dorsoventral patterning. We isolated a maternally expressed and dorsal organizer localized member of the frizzled family of wnt receptors. Wild-type and dominant, loss-of-function molecules in misexpression studies demonstrate frizzled function is necessary and sufficient for dorsal mesoderm specification. frizzled activity is antagonized by the action of GSK-3, and we show GSK-3 is also required for zebrafish dorsal mesoderm formation. frizzled cooperatively interacts with the maternally encoded zebrafish wnt8 protein in dorsal mesodermal fate determination. This frizzled -mediated wnt pathway for dorsal mesoderm specification provides the first evidence for the requirement of a wnt-like signal in vertebrate axis determination.     

Initial experience with endovascular aneurysm repair: comparison of early results with outcome of conventional open repair

PURPOSE: To determine the safety, effectiveness, and problems encountered with endovascular repair of abdominal aortic aneurysm (AAA). Initial experience with endoluminal stent grafts was examined and compared with outcome for a matched concurrent control group undergoing conventional operative repair of AAA. METHODS: Over a 3-year period, 30 patients underwent attempts at endovascular repair of infrarenal AAA. Of the 28 (93%) successfully implanted endografts, 8 were tube endografts, 8 bifurcated grafts, and 12 aortouniiliac grafts combined with femorofemoral bypass. Most of the procedures were performed in the past year because the availability of bifurcated and aortoiliac endografts markedly expanded the percentage of patients with AAA who might be treated with endoluminal methods. The follow-up period ranged from 1 to 44 months, with a mean value of 11 months. RESULTS: Endovascular procedures demonstrated significant advantages with respect to reduced blood loss (408 versus 1287 ml), use of an intensive care unit (0.1 versus 1.75 days), length of hospitalization (3.9 versus 10.3 days), and quicker recovery (11 versus 47 days). Although the total number of postoperative complications was identical for the two groups, the nature of the complications differed considerably. Local and vascular complications characteristic of endovascular repair could frequently be corrected at the time of the procedure and tended to be less severe than systemic or remote complications, which predominated among the open surgical repair group. On an intent-to-treat basis, 23 (77%) of the 30 AAAs were successfully managed with endoluminal repair. The seven (23%) failures were attributable to two immediate conversions caused by access problems, three persistent endoleaks, one late conversion caused by AAA expansion, and one late rupture. CONCLUSIONS: Although less definitive than those for conventional operations, these early results suggest that endovascular AAA repair offers considerable benefits for appropriate patients. The results justify continued application of this method of AAA repair, particularly in the treatment of older persons at high risk.     

Surgical treatment of choledochal cyst in adults: results and long-term follow-up

BACKGROUND/AIMS: Results of the surgical management of 60 adults with choledochal cysts at Chang Gung Memorial Hospital Taipei are presented. PATIENTS AND METHODS: All patients were diagnosed and surgically managed during the period between March 1979 and December 1992. There were 47 females and 13 males, with ages ranging from 16 to 81 years (mean age = 31.9 years). Of the total, there were 41 Type I, one Type II, 14 Type IV, and four Type V choledochal cysts classified according to Todani's classification system. The definite surgical procedures were cyst excision and hepatico-jejunostomy in 43 cases in type I and IV diseases, one cyst excision in type II disease, two hepatectomy for type V disease, cyst enterostomy in seven cases, and T-tube choledochocystostomy in seven cases. RESULTS: The operative mortality rate was 3.3% and the complication rate related to the surgical procedure was 20%. Early postoperative complications include wound infection, leakage of anastomosis, acute pancreatitis, septic shock, left pleural effusion, and intra-abdominal abscessing. Reoperations were needed in the early postoperative days in two cases due to hepatico-jejunostomy leakage and intraabdominal abscess formation. Long-term surgical outcome, concerning recurrence of symptoms, was related to the following factors, excluding the factors of surgery: presence of bile duct lithiasis, common channel less than 22 mm, presence of preoperative pancreatitis and acute angle type pancreaticobiliary unions. Only common channel less than 22 mm is statistically significant. The percentage of recurrence of the symptoms after resectional surgery was 32.5% in the long term follow-up period. Most of the cases responded well to an antibiotics treatment. Three of the cases required a second operation or PTCD as well as dilatation to treat the recurrent cholangitis. CONCLUSION: Although the recurrence of symptoms is not uncommon and satisfactory explanation of the analysed factors is still the treatment of choice for adult patients with choledochal cysts.     

Detection of antisperm antibodies in seminal plasma by flow cytometry: comparison with the indirect immunobead binding test

OBJECTIVE: To compare flow cytometry with the established indirect immunobead binding test (IBT) for the detection of antisperm antibodies in seminal plasma. DESIGN: A prospective, comparative study. SETTING: University-based andrology unit. PATIENT(S): One hundred and fifty-eight men with suspected male factor subfertility. INTERVENTION(S): Seminal plasma samples were incubated with antisperm antibody-negative donor sperm. Surface-bound antibody was detected with fluorescence-labeled antihuman antibody in the flow cytometry assay or with immunobead-labeled antihuman antibody in the IBT. MAIN OUTCOME MEASURE(S): The percentage of sperm that tested positive for surface-bound antibody was determined in the two assays. Seminal plasma was antisperm antibody-positive when > or = 20% of the sperm were antibody-bound, and clinically significant levels were present when > or = 50% of the sperm were antibody-bound. RESULT(S): Of 71 samples that were negative by the IMT, 66 (93%) also were negative by flow cytometry. Of 63 samples that had > or = 50% immunobead binding, 55 had equivalent results by flow cytometry. Overall statistical analysis showed a good correlation between the two assays. CONCLUSION(S): There is a good correlation between the indirect IBT and indirect flow cytometry for the detection of antisperm antibodies in seminal plasma.     

Retrospective study of postcraniotomy headaches in suboccipital approach: diagnosis and management

PURPOSE: The suboccipital approach used for cerebellopontine angle tumors, microvascular decompression, vestibular nerve section, and other procedures has been associated with significant postoperative headache. This study was undertaken to evaluate retrospectively the incidence and management of headaches in these patients. METHODS: Operation logs from 1988 through 1993 were reviewed to identify patients who underwent lateral suboccipital craniotomy or craniectomy. The nature of the operation, preoperative and postoperative complaints of headache, treatment for postoperative headache, and the use of primary cranioplasty were recorded from the medical records. RESULTS: Fifty-six suboccipital approaches were performed by the senior authors between 1988 and 1990. Seven patients had debilitating postoperative headaches. None responded to conservative management, and all underwent secondary cranioplasty. All seven patients showed significant improvement in their pain, with four of seven requiring no other treatment (follow-up from 15 to 38 months). Fifty patients underwent cranioplasty at the time of their initial operation, from 1991 to 1993. No case of debilitating headache was identified post-operatively in these patients. CONCLUSIONS: Cranioplasty at the time of lateral craniectomy appears to reduce the incidence of debilitating postoperative headache.