Attenuation of reperfusion injury by renal ischaemic preconditioning: the role of nitric oxide

OBJECTIVE: To determine the effect on nitric oxide (NO) release and renal NO synthase (endothelial, eNOS and inducible, iNOS) activity of renal ischaemia-reperfusion (I/R) in vivo in an animal model, and to examine the possible involvement of NO in ischaemic preconditioning (IP) of the kidney. MATERIALS AND METHODS: In a right-nephrectomized rat model, 42 animals were randomized in four groups: controls; IP-only (4 min of ischaemia followed by 11 min of reperfusion, total of four cycles); renal warm ischaemia (45 min) and 6 h reperfusion; ischaemia (45 min) preceded by IP pretreatment. Serum NO metabolites were assayed 2 and 6 h after ischaemia or the control equivalent. NOS expression in the kidney was detected immuno-histochemically, and damage assessed morphologically in sections stained with haematoxylin and eosin. Kidney function was assessed by the levels of serum creatinine, urea and electrolytes. RESULTS: Compared with before ischaemia, the concentration of serum NO metabolites at 6 h was increased in the IP-only animals (P = 0. 016) and in the IP + I/R group (P = 0.002). There was greater eNOS expression in the IP-only group (P = 0.009) and in the IP + I/R group than in controls (P = 0.050). iNOS expression was greater in the IP-only animals than in the control group (P = 0.050). Histological assessment showed less evidence of cellular damage in IP + I/R animals than in the I/R-alone group (P = 0.020). Serum creatinine level was not significantly different between the IP-only group and the control. There were no differences after 2 h of reperfusion. CONCLUSION: Ischaemic preconditioning has a protective effect on renal structure and function, which may be produced by increased NO release arising from increased NOS expression by 6 h after reperfusion.     

The impact of violence on mothers' and children's needs during and after parental separation

Men's violence against mothers and children as a context of separation significantly increases the immediate and longer-term parenting needs of affected children, according to a South Australian study of single mothers' transition and adaptation to living in a single parent household. Qualitative research interviews with 18 separated mothers who cited violence as the main reason for ending their relationship included mothers' views on how the violence had impacted on their children. Mothers who had fled violence named continuing concerns with their children's behaviour including withdrawal, anxiety and aggression, as well as the children's continuing exposure to violence during contact with their father. These mothers reported that access to professionals to seek help with their concerns about their children's needs was often inadequate.     

The form of sympathetic postganglionic axons at clustered neuromuscular junctions near branch points of arterioles in the submucosa of the guinea pig ileum

Summary In fluorescence histochemical studies of the sympathetic innervation of the arterial vessels of the submucosa of the guinea pig ileum, we have identified clusters of varicosities overlying arteriolar branch points. These were particularly obvious on the small arterioles < 45 m in diameter, the non-branching regions of which generally lack much other innervation. Serial reconstruction from electron micrographs of axon bundles from the region of arteriolar branch points revealed the form of the varicose axons. Branching of axon bundles sometimes involved branching of individual axons. Within a cluster, most axons had several varicosities along lengths as short as 3 m. The varicosities were very irregular in size and shape. Most large varicosities (>1 m in diameter) that were bare of Schwann cell covering (73%) formed neuromuscular junctions with basal lamina intervening between axon and muscle membranes. A smaller proportion (44%) of small varicosities (0.5–1.0 m diameter) also formed junctions. Of all bare varicosities, 37% did not form contracts. In several of the large varicosities, prejunctional membrane specializations were identified over part of the neuromuscular junctions.     

Prognostic scoring in colorectal cancer liver metastases: development and validation

HYPOTHESIS: A prognostic scoring system for colorectal cancer liver metastases that is derived from unselected patients referred for hepatic resection would improve the applicability and increase the accuracy of prognostication. DESIGN: Retrospective analysis of prospectively documented data; validation against an unrelated cohort from another institution. The median follow-up was 16.4 months (95% confidence interval, 15.0-17.8 months) (original cohort). SETTING: Two tertiary referral centers at unrelated university hospitals. PATIENTS: Independent prognosticators of survival were derived from 337 patients with colorectal cancer liver metastases referred for consideration of liver resection, and prognostic scores were calculated in 269 patients (79.8%) (original cohort). Calculation of prognostic scores was also applied to 193 patients referred and treated in an unrelated institution (validation cohort). MAIN OUTCOME MEASURES: Kaplan-Meier survival curve analysis (log-rank test) between different prognostic groups in the original and the validation cohorts. RESULTS: Independent prognosticators of survival were Dukes stage, number of metastases, and serum concentrations of carcinoembryonic antigen, alkaline phosphatase, and albumin. Significant differences were found in cumulative overall survival between patients assigned to good, moderate, and poor prognoses in the original and validation cohorts (P<.05). Liver resection improved survival in all prognostic groups. However, no patient with poor prognosis and only 19.7% (13 of 66) of patients with moderate prognosis survived 5 years, compared with 62.5% (10 of 16) of patients with good prognosis (P<.001). CONCLUSIONS: This prognostic scoring system is derived from and can be applied to patients with colorectal cancer liver metastases at the time of referral for consideration of surgery. Patients with poor prognosis have no long-term benefit from curative liver resection and should therefore be considered for combined multimodal treatment.     

Third Prize: Comparison of radical nephrectomy, laparoscopic microwave thermotherapy, cryotherapy, and radiofrequency ablation for destruction of experimental VX-2 renal tumors in rabbits

BACKGROUND AND PURPOSE: Currently available minimally invasive renal tumor-ablation procedures include cryotherapy, radiofrequency ablation, and microwave thermotherapy. In this study, we investigated the ability of these three approaches to destroy experimental renal tumors in rabbits. The mechanism of potential tumor metastasis was also explored. MATERIALS AND METHODS: The VX-2 tumor line is an aggressive rabbit epidermoid tumor with a high metastatic potential. An initial experiment comparing cooled-tip microwave thermotherapy with cryotherapy and radical nephrectomy for treatment of small VX-2 tumors revealed that all microwave-treated rabbits had local recurrence and that several also had diffuse intraperitoneal carcinomatosis. In view of these results, a second experiment was performed in which 45 New Zealand White rabbits were implanted laparoscopically with VX-2 xenografts underneath the kidney capsule and divided into five groups of 9 each. The test groups were microwave thermotherapy with a 3.5-mm cooled-tip probe, microwave thermotherapy with a 3.5-mm noncooled- tip probe, radiofrequency ablation with a 1.5-mm cooled-tip probe, radiofrequency ablation with a 1.5- mm non-cooled tip probe, and cryotherapy with a 2.3-mm cryoprobe. The control groups were five rabbits that were not treated, five rabbits with tumors that had the tumor pierced with a probe but were untreated, and five rabbits that underwent nephrectomy after piercing of the tumor. Treatment was initiated 5 days after tumor implantation. One month later, all animals were euthanized and autopsied. RESULTS: At 5 days after tumor implantation, laparoscopic inspection revealed no visible peritoneal metastases. At 1 month, in the cooled and non-cooled microwave-thermotherapy groups, carcinomatosis occurred in five and six of nine animals, respectively. In comparison, carcinomatosis was detected in two of nine animals in the cryotherapy group at autopsy. With respect to cooled and non-cooled radiofrequency ablation, carcinomatosis was observed in four of nine rabbits in each group. In the control groups, none of the animals with unpierced tumors exhibited carcinomatosis, while carcinomatosis was seen in two of the five rabbits with tumor violated by piercing and in three of the five rabbits that underwent immediate nephrectomy after piercing of the tumor. CONCLUSION: Carcinomatosis occurred most frequently in animals treated with microwave thermotherapy, followed by radiofrequency ablation, and lastly cryoablation. The simple act of piercing a highly aggressive tumor can result in local spread. More disconcerting, and less well understood, is why certain ablative modalities appear to increase the rate of intraperitoneal spread.     

Retained Grafenberg Ring for 39 years Discovered During Abdominal Hysterectomy

Summary: A 71-year-old female with a Grafenberg ring retained for 39 years is described. At operation, the device was presenting beneath the serosal surface of the posterior uterine wall. The literature is briefly reviewed.     

Postmortem MR imaging of the fetus: an adjunct or a replacement for conventional autopsy?

Fetal and perinatal autopsy provides essential diagnostic information not only for parents but also for medical audit and clinical trials. The autopsy rate is decreasing throughout the world for numerous reasons. Medical imaging has always been part of the autopsy process, but in the last decade there has been increased interest in imaging as additional to or a replacement for autopsy. This is especially so with the wider availability of magnetic resonance (MR) scanners that are able to provide detailed anatomy of all body structures as well as having the potential to provide information about histopathological patterns of injury. Postmortem MR imaging (MRI) provides similar information to autopsy for gross pathology of most organ systems. It often provides more information in cases of central nervous system abnormalities, but is less accurate for cardiac abnormalities. Targeted, image-guided biopsy may allow histological diagnosis following postmortem MRI.