Laparoscopic assisted vaginal hysterectomy: one group's experience

Laparoscopic assisted vaginal hysterectomy (LAVH) has been reported worldwide. We report our experience with LAVH in 51 patients, 23 with the laparoscopic stapling device, 12 with a combination of stapler and bipolar coagulation, and 16 by bipolar coagulation exclusively. No operations were converted to laparotomy, and there were few minor complications. Average operating time was 1 h and 38 min. Hospital stay averaged 2.2 days. Average hospital costs were greater for the stapling devices ($7815.00) compared with bipolar coagulation ($7150.00). Postoperative patient satisfaction was high (96%), with high resolution of the symptoms (94%). We conclude that LAVH is a safe, effective operation in selected cases and may be a valid alternative to abdominal hysterectomy.     

Leak detector in medical gas delivery systems

We describe an original device developed by the biomedical technicians of the University Hospital of Nancy for checking tightness and measuring the capacity of medical gas pipeline network. A leak can be assessed either as a loss of pressure or as a loss of volume per unit of time (cmH2O.min-1 and mL.min-1 respectively). To assess the latter, the capacity of the explored pipeline must have been measured when it still was gas-tight. With the device, a leak can be assessed within a few minutes whereas the official procedure requires a delay between 1 and 24 hours. The device still has to undergo bench evaluation and validation.     

An in vivo model of femtosecond laser intrastromal refractive surgery

BACKGROUND AND OBJECTIVE: To develop an animal model for evaluation of femtosecond laser intrastromal refractive surgery. METHODS: Intrastromal photodisruption was performed in New Zealand Albino rabbits using a femtosecond laser system. This surgical pattern consisted of a 100 microm-tick pyramid of laser pulses starting 180 microm below the corneal surface. Animals underwent serial slit lamp examinations and corneal thickness measurements at 1,3,7,14, and 28 days, then monthly up to 1 year. RESULTS: Approximately 70 microm of central corneal thinning were seen at 1 week, remaining stable up to 7 months. CONCLUSIONS: Intrastromal photodisruption with femtosecond lasers produced consistent changes in corneal thickness without loss of corneal transparency. These changes were more stable than those produced with excimer laser procedures in a similar animal model.     

Multivariate Analysis of Left Ventricular Mass Determinants in Adults: Different Patterns in Men and Women

Echocardiographic left ventricular mass (LVM) estimates are strong predictors of subsequent mortality and cardiovascular events. It is known that blood pressure (BP), weight (WT), and age are significantly correlated with LVM. We hypothesized that stroke volume (SV) measured by Doppler echocardiography would also be correlated with LVM. Two hundred and thirteen patients referred for routine echocardiography had determination of LVM, cuff BP, and Doppler SV. Those with localized LV disease, valvular disease, or cor pulmonale were excluded. In both men and women, systolic BP (SBP) was more closely correlated with LVM than was diastolic blood pressure or mean arterial pressure, and SV was more closely correlated with LVM than cardiac output or cardiac index. Stepwise regression, followed by multiple regression showed that four variables (WT, SV, SBP, and AGE) explained 32.3% of the variability in LVM in men and 48.5% of the variability in LVM in women. WT and SV were significant determinants of LVM in both men and women. Age was also significant in men and SBP was also significant in women. For both men and women, SV was more significantly correlated with LVM than was SBP. The changes in LVM associated with 1 SD increments of SV and SBP, respectively, were 8 and 5 g for men and 13 and 11 g for women. We conclude that men and women have different patterns of variables influencing LVM. Doppler echocardiographic SV is a newly described determinant of LVM that has a greater correlation with LVM than does SBP. This study reemphasizes the importance of WT as the major determinant of LVM. (ECHOCARDIOGRAPHY, Volume 13, January 1996)     

How important is adequate radiotherapy for the long-term results of breast-conserving treatment?

The influence of radiotherapy dose parameters on longterm local control was studied in 134 clinical stage I-II breast cancer patients treated by tumorectomy and telecesium therapy during the 1960s. Recurrence in the breast was more frequent in patients receiving 75 Gy or less to the tumor bed (31% versus 15% for higher doses, p less than 0.05), and weekly dose rates of less than 8 Gy/week were associated with increased local-regional failure (30% versus 15% for higher weekly doses, p less than 0.01). The majority of local-regional failures were observed in the 53 patients having "inadequate" total or weekly radiotherapy doses (18/53, 34% versus 9/81, 11%, p less than 0.001). The importance of adequate radiotherapy applied to both older patients, as well as those younger than 40, who appear inherently to have a higher risk of local relapse. The mean interval to recurrence was markedly longer for inadequate radiotherapy (111 months, versus 75 months for adequate treatment), so that significant differences in local control became apparent only after 5 years. These results underscore the importance of radiotherapy technique in breast-conserving treatment, and suggest that an excessive reduction in the intensity of radiotherapy may result in an inordinate number of late local failures.     

Stimulation of Na+/H+ exchange is not required for induction of hypertrophy of renal cells in vitro.

Hypertrophy of renal proximal tubular cells is associated with an early increase in Na+/H+ antiport activity both in vivo and in vitro. The purpose of the study presented here was to determine whether functioning Na+/H+ antiport activity is required for hypertrophy to occur. LLC-PK1 cells deficient in Na+/H+ antiport activity were prepared by the "proton-suicide" method. Mutant cells had 28 to 40% of the normal Na+/H+ antiport activity. The addition of 50 nM methylisobutylamiloride to these cells decreased the antiport activity to less than 5% of the control value. In the mutant cells, steady-state intracellular pH was normal as was the protein content. After exposure of the wild-type cells for 72 h to 10(-6) M insulin and 10(-9) M insulin-like growth factor 1, cell protein content increased significantly. The increase in protein content induced by these growth factors in the mutant cells did not differ significantly from the response of the wild-type cells. Lowering the Na+/H+ exchange further by the addition of methylisobutylamiloride (50 nM) to less than 5% of the control value did not blunt the hypertrophic response in the mutant cells. These studies indicate that hypertrophy can be induced in LLC-PK1 cells by growth factors when basal Na+/H+ antiport activity is reduced to low levels by selective mutation or by competitive inhibition. The results suggest that stimulation of the Na+/H+ antiporter is not an essential prerequisite for the induction of hypertrophy in renal cells.     

Circulating growth factor levels are associated with tumorigenesis in neurofibromatosis type 1.

PURPOSE: Neurofibromatosis type 1 (NF1) is characterized by systemic development of neurofibromas. Early clinical diagnosis can be ambiguous, and genetic diagnosis can be prohibitively difficult. Dysregulation of a number of growth factors has been suggested to be a mechanism of pathogenesis. This study was performed to assess the contribution of circulating growth factors for diffuse tumorigenesis and the diagnostic value of circulating growth factor identification in serum. EXPERIMENTAL DESIGN: The growth stimulation of neurofibroma-derived cells by serum from NF1 patients was tested, and serum growth factor levels in a cohort of NF1 patients (n = 39) between the ages of 7 and 70 years were analyzed. RESULTS: Concentrations of midkine (MK) and stem cell factor, but not epidermal growth factor, were substantially increased in serum of NF1 patients when compared with healthy controls. Within the NF1 group, MK levels increased dramatically at puberty from an average of 0.79 ng/mL in patients <18 years to 1.18 ng/mL in patients >18 years old. Stem cell factor and MK concentrations above a defined threshold in serum of NF1 patients are of diagnostic benefit for 96% of patients in the cohort tested. Furthermore, serum from NF1 patients enhanced proliferation of human neurofibroma-derived primary Schwann cells and endothelial cells substantially better than normal serum. CONCLUSIONS: Enhanced circulating growth factor levels contribute to diffuse tumorigenesis in NF1 and may provide the basis for molecular diagnosis.