loop electrosurgical excision procedure: a review of our recent experience

OBJECTIVE: To investigated whether persistence or recurrence of cervical intraepithelial neoplasis (CIN) is associated with an involved excisional margin during loop electrosurgical excision procedure (LEEP). METHODS: The records of 256 consecutive LEEP were studied. After LEEP, all patients were followed up by colposcopy and cytology at 4 to 6 month intervals for at least two years. A patient was classified as having persistent disease if SIL was seen within one year of treatment or recurrent disease if SIL was detected after one year of treatment. All relevant patient details including cytology, colposcopy findings, treatment histology, complications, recurrence or persistence of disease entered into a computer database. RESULTS: Complications occurred in 8 patients (3.1%). LEEP was successful in treating 226 patients (95.4)%. Eleven patients (4.6%) had persistent SIL. Involvement of the resection margin was a significant risk factor for persistent disease (3.1% for uninvolved margins vs 11.4% for involved margins, P < 0.05). Similarly, recurrent disease occurred in 9.1% of patients with involved resection margins vs 2.1% with uninvolved margins (P < 0.05). Eleven patients (4.3%) had microinvasive carcinoma. Only 3 were identified by colposcopy and directed biopsy. CONCLUSION: LEEP is established as a safe and efficacious method for the treatment of CIN, long term morbidity including the effect on subsequent fertility must be observed.     

Total mercury and methylmercury levels in some New Zealand commercial marine fish species

Two groups of samples spanning 16 years are reported for methylmercury and total mercury. All the samples had been taken from commercial catches and represent 33 different commercially important New Zealand marine fish species. Results show the New Zealand fish species sampled have mean contents of total mercury that range between 0.02 and 2.48 mg kg^-1 and mean contents of methylmercury that range from less than 0.04 to 1.97 mg kg^-1.     

Neurotoxic effects of feline immunodeficiency virus, FIV-PPR

Apoptotic neuronal death is known to occur in the developing brain and in the mature brain of patients with ischemic and degenerative disorders. Although microglial cells are known to become activated in specific conditions, it has not been elucidated whether they enhance or prevent neuronal apoptosis. The present study was intended to observe how microglial cells are involved in neuronal death. When rat primary cortical neurons were incubated with a nitric oxide (NO) donor sodium nitroprusside (SNP; 300 microM) for 10 min, neuronal death occurred 12-16 hr later. The NO-induced neuronal death was inhibited by cycloheximide, and the SNP-treated neurons were characterized by nuclear fragmentation and intact cell membrane under electron microscopy. Agarose gel electrophoresis demonstrated DNA fragmentation of the SNP-treated neurons. Thus, the NO-induced neuronal death appeared to be apoptosis. When neurons were cocultured with rat primary microglial cells, the SNP treatment failed to induce the neuronal death. Because microglia-conditioned medium also prevented apoptotic neuronal death, microglial cells were considered to secrete antiapoptotic factors. The microglia-conditioned medium rescued neurons even when they were added to neuronal cultures after the SNP treatment, implying that the factors acted on neurons in a manner other than scavenging NO. Interleukin-3, interleukin-6, macrophage colony-stimulating factor, and basic fibroblast growth factor, which are known to be secreted by microglial cells, were not effective in preventing NO-induced neuronal death. Among microglia-derived substances, tumor necrosis factor alpha and plasminogen, which are heat-labile proteins, inhibited neuronal apoptosis. The neuroprotective action of the microglia-conditioned medium, however, still remained, even after it was heated. These findings suggest that microglial cells protect neurons against NO-induced lethal damage by secreting heat-labile and heat-stable neuroprotective factors in vitro.     

Effect of 6-aminonicotinamide on the pentose phosphate pathway: 31P NMR and tumor growth delay studies

6-aminonicotinamide (6AN) has been shown to enhance radiosensitivity in vitro, although previous in vivo studies failed to show an effect. 31P NMR spectra were obtained by using a one-dimensional chemical shift imaging technique on a first generation transplant of the CD8FI spontaneous mammary carcinoma tumor model. Spectra were obtained both before and 10 h after treatment with 6AN (20 mg/kg). Changes in pH, nucleoside triphosphate/inorganic phosphate, and phosphocreatine/ inorganic phosphate measured at 10 h post-6AN were not significant. A new peak was detected 10 h post-6AN, which was assigned to 6-phosphogluconate (6PG), indicating inhibition of the pentose phosphate pathway (PPP). Based on the spectral data demonstrating inhibition of the PPP at 10 h post-6AN, tumor-bearing mice were irradiated (15 Gy x 3 fractions) on Days 1, 10 or 11, and 21 10 h after administration of 6-aminonicotinamide (20 mg/kg). Tumor-bearing mice receiving 6AN alone (20 mg/kg x 3), radiation alone (15 Gy x 3), or saline were also studied. Tumor growth delay studies indicated that 6AN alone induced a small but significant tumor growth delay (4.3 +/- 0.8 days). Radiation alone induced a tumor growth delay of 34.5 +/- 2.7 days. Treatment with 6AN followed by radiation induced a tumor growth delay of 57.0 +/- 3.8 days. This was significantly greater than the TGD values for treatment with 6AN alone or radiation (P < 0.01). No complete regressions were noted after treatment with 6AN or radiation alone. Concomitant therapy with 6AN plus radiation yielded 6/28 complete regressions (21%), which was significantly greater than radiation (P < 0.05) or 6AN alone (P < 0.01) on this mammary carcinoma.     

Does Helicobacter pylori infection affect gastric emptying in patients with functional dyspepsia?

The objectives of the study were first, to determine if gastric emptying was altered in patients with functional dyspepsia with and without Helicobacter pylori infection compared with normal healthy volunteers; and second, to determine if there were further alterations in gastric emptying when the infection was eradicated. Gastric emptying was measured using a 99mtechnetium radiolabelled solid meal and gastric emptying time was measured as t1/2, viz. time taken for half the radiolabelled meal to be emptied from the stomach. The mean gastric emptying time for H. pylori-positive patients (n=20) was 56.4+/-24.8 min; H. pylori-negative patients (n=19) 67.8+/-31.8 min; and normal controls (n=20) 58.8+/-18.8min. No significant difference was obtained between the groups (ANOVA; P=0.348). Thirteen of 18 H. pylori-positive patients successfully eradicated the infection following treatment with omeprazole 40 mg o.m. and amoxycillin 500 mg t.d.s. for 2 weeks. The mean difference in the gastric emptying time before and after H. pylori eradication was 23.9+/-13.2 min (P= 0.556). There was no significant difference in the frequency of specific dyspeptic symptoms as well as the overall mean symptom score between the H. pylori-positive and -negative patients. Gastric emptying was not different between patients with functional dyspepsia and normal controls. Helicobacter pylori infection does not appear to affect gastric emptying in patients with functional dyspepsia.     

Central pontine myelinolysis at autopsy; a twelve year retrospective analysis

Central pontine myelinolysis (CPM) was first described in 1959 and only later was associated with a rapid, sustained rise in serum sodium from a hyponatremic baseline. This discovery in 1981 led to modifications in recommendations for clinical treatment of hyponatremia. Our interest has been in tracking the incidence of CPM found at autopsy by year to see whether changes in medical treatment in hyponatremia have resulted in a decrease in CPM over time. Clinically asymptomatic CPM found at autopsy has always been at least as frequent as cases diagnosed premortem and serves as a reasonable indicator for the incidence of the disease. In over 3,000 autopsies, on most of which the brain was examined macroscopically and microscopically by the same neuropathologist, we have discovered 15 cases of asymptomatic, small pontine CPM. Of these 15, 6 were active lesions and 9 were remote; in the active group, 5 of the 6 cases were associated with a rapid, sustained rise in serum sodium during the appropriate time period. The incidence of asymptomatic CPM has remained steady over the 13-year time period. In contrast, we have encountered no cases of CPM diagnosed premortem that have come to autopsy in the same time period. These cases emphasize that CPM still occurs, but most often as an asymptomatic disorder with small, midline pontine lesions. When small active CPM is found, it still is associated with a rapid sustained rise in serum sodium.     

Human intramuscular and cutaneous pain: psychophysical comparisons

We used psychophysical methods to compare the central processing of nociceptive inputs from skin and muscle in ten normal humans. Both intramuscular electrical and infrared CO2 laser cutaneous stimulation showed increasing but decelerating (downward concave) stimulus-response curves and similar temporal summation characteristics. Intramuscular stimulation was rated significantly more unpleasant than cutaneous stimulation. The results are consistent with a common mode of central nociceptive processing for skin and muscle pain intensity but suggest a relatively larger activation of affective mechanisms by muscle afferents.