The taming of immunohistochemistry: the new era of quality control.

The most critical factor for interpreting the results of immunohistochemistry is verification of antibody sensitivity and specificity. While some manufacturers supply material data sheets with this information, many do not. This paper describes a well-defined quality assurance program for testing immune reagents. This program can be used to provide commercial suppliers of antisera with analyses of their products destined for government licensure applications. This paper illustrates the protocol and explains the testing philosophy developed over the last eight years.

Sexually transmitted papillomaviral infection in the male: VI. Simultaneous urethral cytology-ViraPap testing of male consorts of women with genital human papillomaviral infection.

A series of 122 males at high risk for development of human papillomavirus (HPV) infection were prospectively studied with simultaneous urethral brushing cytology and ViraPap, to establish their relative sensitivity and specificity in relation to the diagnosis of HPV infection in the urethral canal. The prevalence of disease in this high-risk population was 10 percent. The sensitivity of DNA hybridization was determined to be 67 percent, with a 100 percent specificity, as compared with a 25 percent sensitivity of cytologic analysis. Physical examination alone had a 75 percent sensitivity. Physical examination with ViraPap urethral analysis identified all patients with urethral HPV-associated disease. These results indicate that clinical examination alone misses one quarter of the HPV-involved patients.

Superficial laser vulvectomy. II. The anatomic and biophysical principles permitting accurate control over the depth of dermal destruction with the carbon dioxide laser.

The rationale for using the carbon dioxide laser to treat either vulvar intraepithelial neoplasia or extensive papillomaviral infections is to destroy the entire area of abnormal epithelium to a shallow depth, so that rapid healing will occur from normal keratinocytes in the underlying pilosebaceous glands. After the first laser impact, anatomic landmarks in the crater base are disguised by a layer of charred proteins, and any structure that is visible will already have suffered thermal necrosis. Accurate control of depth depends upon special surgical strategies that correlate the level of the underlying zone of thermal necrosis with specific visual appearances within the zone of vaporization. Maneuvers that limit depth of penetration to one of three desirable surgical planes (basement membrane, papillary dermis, midreticular dermis) are described.

Studies on oxidative phosphorylation and steroidogenesis by ovarian mitochondria after gonadotropic stimulation.

No differences in oxidative phosphorylation or in the per cent of [4-14C]progesterone were found in ovarian mitochondria of immature rats after treatment with 20 IU of pregnant mare serum gonadotropin (PMSG) iv 30 min before killing. However, treatment of immature rats with 20 IU of PMSG sc 54 h prior to killing decreased the ADP:O ratio and increased the per cent of [4-14C]cholesterol conversion. Electron microscopic studies showed that mitochondria with lamellar cristae were prominent in ovaries of untreated rats, while large pleomorphic mitochondria and mitochondria with tubulovesicular cristae dominated in ovaries of PMSG-treated rats. Ovarian homogenates separated by zonal centrifugation showed three peaks od cytochrome oxidase activity which shifted to the heavier end of the gradient after PMSG treatment. These studies suggest that PMSG treatment influences ovarian mitochondria, possibly by stimulating the synthesis of additional functional components and/or the biogenesis of new mitochondria. Aminoglutethimide addition to bovine luteal mitochondria decreased steroidogenesis by 60% when succinate was used as substrate. However, there was a 16% increase in the ADP:O ratio, apparently due to a decrease in oxygen utilization. When oligomycin was added to luteal mitochondria, there was a 30% decrease in the ACP:O ratio but a 300% increase in [4-14C]cholesterol conversion. Dinitrophenol also decreased mitochondrial steroidogenesis. These results suggest that energy obtained from succinate oxidation can be diverted from phosphorylation to support steroidogenesis.

Transmural mitochondrial differences in myocardium.

Two functional mitochondrial populations with different sedimentation rates (S) were obtained from homogenates of canine myocardium by rate zonal centrifugation using an iso-osmotic Ficoll gradient. To ascertain the origin of these populations, the left ventricular wall of normal myocardium was divided into subepicardial (outer one-third), intermediate (middle on-third), and subendocardial (inner one-third) layers. The slow S mitochondria comprised 75% of the mitochondrial population of the subepicardial layer. In contrast, the fast S mitochondria contributed 65% of the subendocardial population. Intermediate layer mitochondria resembled those of the subepicardium. Mitochondria isolated from the three layers had approximately the same density, as shown by isopycnic zonal centrifugation. These studies indicate that mitochondria from subepicardial and subendocardial layers of normal myocardium differ in size and shape but not in density. Electron micrographs (EM) of the subepicardium showed many mitochondria as long as 4 to 8 sarcomeres. Mitochondria from the outer and inner layers of normal myocardium had the same oxidative phosphorylation parameters. Acute myocardial infarction, lasting 1 or 2 hr, resulted in the selective loss of the fast S mitochondria. Because the fast S mitochondria are prevalent in the subendocardium, these results may explain the greater vulnerability of this layer to anoxia.