Colon perforation following percutaneous nephrostomy and renal calculus removal

Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal.     

Significance of dopamine transmission in the rat medial prefrontal cortex for conditioned fear

Previous studies have demonstrated activation of dopamine transmission in the medial prefrontal cortex (mPFC) by conditioned fear stimuli. Therefore, the present study investigated the functional significance of mPFC dopamine for a conditioned fear response to a tone. We examined the effects of inhibition or stimulation of mPFC dopamine transmission by local microinfusion of the D1/D2-receptor antagonist cis-flupenthixol or the indirect dopamine receptor agonist D-amphetamine, respectively, in a classical fear-conditioning paradigm in Wistar rats. Rats received tone-shock pairings and were later exposed to the tone alone. Freezing was used as measure of conditioned fear. Presence of the drugs in the mPFC during the tone-shock pairings did not affect freezing during subsequent presentation of the tone alone. However, when cis-flupenthixol and D-amphetamine were present in the mPFC during presentation of the tone alone, freezing to the tone was reduced. We demonstrated that the decreased freezing could be explained neither by state dependency nor infusion-induced alterations in activity. Our data indicate that mPFC dopamine transmission is important for the retrieval/expression, but not the formation, of conditioned fear. The reduction of conditioned fear by prefrontal infusion of both cis-flupenthixol and D-amphetamine may reflect normal expression of conditioned fear requires an optimal level of mPFC dopamine activity.     

Progressively motile human spermatozoa are well protected against in vitro lipid peroxidation imposed by induced oxidative stress

Semen samples of 24 patients were analysed. Volumes were measured and the numbers of progressively motile (PMS), motile (MS) and nonmotile spermatozoa (NMS) were determined. These 24 samples appeared to show a large variation in motility percentages and numbers. Spermatozoa of these semen samples were isolated from the seminal plasma and exposed to induced radical oxygen stress imposed by iron/ascorbate. Lipid peroxidation (LPO) was quantified as thiobarbituric acid reactive material. The contributions of PMS, MS and NMS were also estimated. It was found that the PMS did not contribute to the formation of lipid peroxides. The cellular radical defence system of PMS may offer them adequate protection against the harsh conditions of radical oxygen stress. Stepwise regression analyses showed that only the population of NMS contributed significantly to the explanation of the variance in LPO production (R2 = 0.56, P < 0.001). Pre-existing membrane lipid peroxides were not detected in spermatozoa. It is therefore suggested that LPO takes place only after radical oxygen stress has exhausted the cellular defence system. LPO is not the initial, but one of the later, events leading to the death of spermatozoa. It is concluded that the population of progressively motile spermatozoa in semen samples does not contribute to the production of thiobarbituric acid reactive substances as induced by in vitro radical oxygen stress.     

Genetic analysis of early- versus late-stage ovarian tumors

In the United States, ovarian cancer is the fourth most common cause of cancer-related deaths among women. The most important prognostic factor for this cancer is tumor stage, or extent of disease at diagnosis. Although women with low-stage tumors have a relatively good prognosis, most women diagnosed with late-stage disease eventually succumb to their cancer. In an attempt to understand early events in ovarian carcinogenesis, and to explore steps in its progression, we have applied multiple molecular genetic techniques to the analysis of 21 early-stage (stage I/II) and 17 advanced-stage (stage III/IV) ovarian tumors. These techniques included expression profiling with cDNA microarrays containing approximately 18,000 expressed sequences, and comparative genomic hybridization to address the chromosomal locations of copy number gains as well as losses. Results from the analysis indicate that early-stage ovarian cancers exhibit profound alterations in gene expression, many of which are similar to those identified in late-stage tumors. However, differences observed at the genomic level suggest differences between the early- and late-stage tumors and provide support for a progression model for ovarian cancer development.     

Predictive values of serum tumour markers tetranectin, OVX1, CASA and CA125 in patients with a pelvic mass

Our objective was to compare the predictive value of the well-established tumour marker CA125 with the newer tumour markers tetranectin (TN), OVX1 and CASA in distinguishing benign and malignant pelvic masses in women. Participants included 185 women, 19 years or older, with a pelvic mass planned for surgical exploration. Significantly different CA125 levels were found between benign tumours and localised ovarian cancer (OC), advanced OC and other non-OCs. Significantly different TN levels were found between benign tumours and advanced OC (stage III/IV), between benign tumours and other cancers and between all OCs and other cancers. For CASA, significant differences were found between benign tumours and all OCs as well as advanced OC. No significant differences could be demonstrated for OVX1. Significant correlations for the 44 OC patients were found between CA125, TN and CASA. No significant correlations were found for OVX1, possibly because of the method used for collection and handling of serum samples. None of the new markers had any additional predictive value compared to CA125. TN and CASA levels correlated with FIGO stage and could be used to discriminate between benign and advanced OC. However, in comparison to the performance of CA125, the additional discriminative value of TN and CASA was minor.