Vulvar intraepithelial neoplasia: Risk factors for recurrence.

OBJECTIVE: We studied a large population of women with high-grade vulvar intraepithelial neoplasia (VIN) in order to identify patient and treatment-related risk factors for recurrence and progression to cancer. METHODS: For this retrospective cohort study of women with a histologic diagnosis of VIN within Southern California Permanente Medical Group between 1995 and 2007 medical records were reviewed; clinical, demographic and pathologic data were collected. Statistical analyses included Chi-squared and Student's t-tests, univariate and multivariate logistic regression, and cumulative incidence analysis. RESULTS: 914 patients with high-grade VIN were identified; 784 met inclusion criteria. We found 26.3% recurrences among treated women, with 2.2% progression to cancer (8.2% among those with recurrence). Risk factors for recurrence on multivariate analysis were: age >50years (OR, 1.44; 95%CI 1.01-2.07), immunosuppression (OR 2.08; 95%CI 1.42-3.06), metasynchronous VAIN or CIN (OR 1.76; 95%CI 1.08-2.88) in addition to margin status (OR 8.17; 95%CI 4.60-14.51) and adjacent LSA (OR 9.91; 95%CI 1.53-31.32) or HPV (OR 2.15; 95%CI 1.13-3.37) with excisional treatment. Recurrence rates did not differ significantly by smoking status and treatment modalities. Median time to recurrence was 16.9months; 25% had late recurrences (44-196months). Cumulative incidence analyses of time to recurrence shows a significantly higher risk among patients over age 50 (log-rank p=0.0031). CONCLUSION: We identified independent risk factors for recurrence including age >50years, immunosuppression, metasynchronous vaginal or intraepithelial neoplasia, positive excision margins, and adjacent lichen sclerosus or human papilloma-virus. Regardless of treatment modality, 25% of recurrences occurred late, highlighting the need for long-term surveillance in women treated for VIN.

Nitric oxide modulates rhythmic slow activity in rat hippocampal slices.

We investigated the role of nitric oxide (NO) in controlling the rate of occurrence of muscarinic rhythmic slow activity (RSA) episodes induced by carbachol in rat hippocampal slices. Typically, a series of several short intervals (< 40 s) between RSA episodes alternated with one or two longer intervals. Treatments with inhibitors of NO synthesis (NG-nitro- or NG-methyl-L-arginine) or with hemoglobin shortened and stabilized all intervals. By contrast, applications of an NO donor (sodium nitroprusside) or membrane permeant cGMP analogs (8-bromo-cGMP or dibutyryl-cGMP) during blockade of NO synthesis lengthened and destabilized the intervals. The importance of cholinergic mechanisms in learning and memory is well known and our findings suggest that NO could influence synaptic plasticity by modulating the occurrence of a muscarinic component of hippocampal RSA.

Roles of the NMDA and quisqualate/kainate receptors in the induction and expression of kindled bursts in rat hippocampal slices.

We used combinations of NMDA and quisqualate/kainate (Q/K) receptor antagonists and low Mg2+ (0.1 mM) solutions to study the respective roles of these receptors during in vitro kindling of interictal bursts in the CA3 area of rat hippocampal slices. Intracellular and extracellular recordings in CA3 showed that Q/K receptors were not necessary for the induction of kindling once the Mg2+ block of NMDA was alleviated, but that the expression of bursts kindled via NMDA-driven mechanisms was Q/K-dependent.

Transition from normal to epileptiform activity in kindled rat hippocampal slices.

We previously demonstrated kindling of synchronized bursts (ISs) by repeated sine-wave stimulation (SW: 2-5 sec, 60 Hz, 20-50 microA, every 5 min) in the CA2/3 area of rat hippocampal slices. Here we report the behavior of individual CA2/3 neurons during the kindling procedure. Intra- and extracellular recordings were obtained concurrently before, during and following SW. Test pulses and SWs were applied in CA2/3 or CA1 stratum radiatum. Neuronal response to to intracellular stimulation was tested by 100 msec depolarizing dc pulses or by 2-20 sec sinusoidal currents. The role of the N-methyl-D-aspartate (NMDA) receptor in the transition from normal responses to ISs was assessed by perfusing the slices with a specific antogonist (DL-2-amino-5-phosphono-valeric acid, APV, 50-200 microM). Our results show that kindling of ISs occurred in two steps: (1) via NMDA-dependent depolarizations during SW, or during SW-induced afterdischarges, and (2) through the recruitment of secondary, late EPSPs (1EPSPs), between consecutive SWs. ISs developed from the 1EPSPs, while the early responses (action potentials, EPSPs, and population spikes) remained unchanged. Kindling of ISs occurred with no changes in resting membrane potential, membrane resistance, or threshold of action potentials. APV did not block kindled ISs, but considerably reduced their amplitude and duration, and increased their frequency. These latter findings suggest that APV-insensitive mechanisms, activated through NMDA-dependent processes, were responsible for the triggering of ISs, and that NMDA receptor systems participated in the control of their rate of occurrence.

Dissociation of insect Malpighian tubules into single, viable cells.

The Malpighian tubules of insects are generally composed of more than one cell type. In the hemipteran Rhodnius prolixus, the tubules are divided into two regions, termed the upper and lower tubules, each of which is composed of a distinct cell type. In the dipteran Aedes taeniorhynchus, primary and stellate cells are interspersed throughout the length of the tubules. We report here techniques for the dissociation of the Malpighian tubules of both of these species into single cells. Tubules are removed from the insect and placed for 1 h in insect Ringer containing elastase (Sigma, type III) at 4 mg/ml. This treatment fully removes the basal lamella. Mild agitation by hand produces a suspension of single cells, which remain viable as determined by Trypan Blue exclusion. Isolated cells have been maintained in cell culture for one week. Using light and scanning electron microscopy, upper and lower tubule cells of Rhodnius and primary and stellate cells of Aedes can be distinguished on the basis of size, shape, microvillar length, and the presence or absence of intracellular crystals.

Extremely-low-frequency magnetic fields disrupt rhythmic slow activity in rat hippocampal slices.

Several studies have indicated that weak, extremely-low-frequency (ELF; 1-100 Hz) magnetic fields affect brain electrical activity and memory processes in man and laboratory animals. Our studies sought to determine whether ELF magnetic fields could couple directly with brain tissue and affect neuronal activity in vitro. We used rat hippocampal slices to study field effects on a specific brain activity known as rhythmic slow activity (RSA), or theta rhythm, which occurs in 7-15 s bursts in the hippocampus during memory functions. RSA, which, in vivo, is a cholinergic activity, is induced in hippocampal slices by perfusion of the tissue with carbachol, a stable analog of acetylcholine. We previously demonstrated that the free radical nitric oxide (NO), synthesized in carbachol-treated hippocampal slices, lengthened and destabilized the intervals between successive RSA episodes. Here, we investigate the possibility that sinusoidal ELF magnetic fields could trigger the NO-dependent perturbation of the rate of occurrence of the RSA episodes. Carbachol-treated slices were exposed for 10 min epochs to 1 or 60 Hz magnetic fields with field intensities of 5.6, 56, or 560 microT (rms), or they were sham exposed. All exposures took place in the presence of an ambient DC field of 45 microT, with an angle of -66 degrees from the horizontal plane. Sinusoidal 1 Hz fields at 56 and 560 microT, but not at 5.6 microT, triggered the irreversible destabilization of RSA intervals. Fields at 60 Hz resulted in similar, but not statistically significant, trends. Fields had no effects on RSA when NO synthesis was pharmacologically inhibited. However, field effects could take place when extracellular NO, diffusing from its cell of origin to the extracellular space,was chelated by hemoglobin. These results suggest that ELF magnetic fields exert a strong influence on NO systems in the brain; therefore, they could modulate the functional state of a variety of neuronal ensembles.

A single-visit cervical carcinoma prevention program offered at an inner city church: A pilot project.

BACKGROUND: A single-visit cervical carcinoma prevention program was implemented, integrating screening, diagnosis, treatment, and health education in the familiar environment of the community church. METHODS: Nonpregnant women age 18 years or older, who had not received cervical carcinoma screening in the preceding year were eligible. Subjects provided information on personal demographics, health, and knowledge regarding cervical carcinoma prevention. Thereafter, cervical cytology was collected, processed, and interpreted on site. Participants attended small-group instruction on cervical carcinoma prevention. Screening results were given to each subject individually. Patients with abnormal cytology underwent immediate colposcopy with biopsies or loop electrosurgical excision procedure as indicated. Participant satisfaction and educational impact were evaluated. RESULTS: Ninety of the 98 participants reported that Spanish was their native language; 59 did not speak English. Fifty-four had had fewer than 6 years of education and 55 were unemployed. Seventy-eight did not have a regular physician or health insurance. Twenty-four either had never undergone cervical carcinoma screening or had let more than 5 years elapse since their previous examination. None of nine potential barriers assessed correlated with past compliance with cervical carcinoma screening. The mean time for processing and on-site interpretation of cervical cytology smears was 22.6 +/- 5.3 minutes. The median time patients spent in the program was 75 minutes. There was a significant improvement in the subjects' knowledge regarding cervical carcinoma prevention. All participants were highly satisfied. CONCLUSIONS: This parish-based, integrated, single-visit program for the prevention of cervical carcinoma was easily implemented and provided care to a substantial proportion of underserved patients.