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Objective: To investigate the effect of transient ischemia-reperfusion on the retina in rats., Methods: Retinal ischemia-reperfusion was induced in rats by increasing the intraocular pressure. After 1 or 5 minutes of ischemia, retinal neuronal cell death at different periods of reperfusion was studied using the TdT-deoxynucleotide terminal nick-end labeling (TUNEL) method and light microscopy. Retinal IL-1 beta and TNF alpha were quantified by an enzyme-linked immunosorbent assay (ELISA)., Results: A few migrating leukocytes were noticed in the retina after transient retinal ischemia-reperfusion. Rare TUNEL-positive (T+) cells were noticed in the outer granular layer or the rod and cone layer, and not in ganglion cell layer in control eyes, but they were significantly increased in the outer granular layer, the inner granular layer, and ganglion cell layer in the eyes treated with 1 or 5 minutes of retinal ischemia-reperfusion (P < 0.05). Retinal IL-1 beta was significantly increased at 6 hours after reperfusion in the eyes treated with 1 or 5 minutes ischemia over the control eyes (P < 0.05), but retinal TNF alpha was not significantly increased (P > 0.05)., Conclusion: Transient retinal ischemia-reperfusion for only 1 or 5 minutes of ischemia can induce the upregulation of retinal IL-1 beta and apoptosis of retinal neuronal cells. This kind of apoptosis in individual cells, however, was not sufficient to affect the whole retinal function.

Previous studies reported that resealed erythrocytes containing rhodanese (CRBC) and NA2S2O3 rapidly metabolize cyanide to the less toxic thiocyanate both in vitro and in vivo. This provided a new conceptual approach to prevent and treat cyanide intoxication. Although the rhodanese-containing carrier cells with thiosulfate as the sulfur donor were efficacious, this approach has potential disadvantages, as thiosulfate has limited penetration of cell membrane and product inhibition of rhodanese can occur due to inorganic sulfite accumulation. In order to circumvent substrate limitation and product inhibition by sodium thiosulfate, organic thiosulfonates were explored. These thiosulfonates have higher lipid solubility than thiosulfate and therefore can replenish the depleted sulfur donor, as they can readily penetrate cell membranes. Also, product inhibition of rhodanese is less apt to occur. This change in sulfur donors should greatly enhance cyanide detoxication, replenish the sulfur donor, and minimize product inhibition of rhodanese. Present studies demonstrate the enhanced efficacy of exogenous organic thiosulfonates over sodium thiosulfate in the CRBC antidotal system to detoxify the lethal effects of cyanide either alone or in combinations with exogenously administered NaNO2. Murine carrier erythrocytes containing purified bovine liver rhodanese were administered intravenously into male Balb/C mice. Subsequently, butanethiosulfonate (BTS) or Na2S2O3 (ip), and NaNO2 (sc) were co-administered prior to KCN (sc). Potency ratios, derived from the LD50 values, were compared in groups of mice treated with CRBC-Na2S2O3 or CRBC-BTS either alone or in combination with NaNO2.(ABSTRACT TRUNCATED AT 250 WORDS)

The silver-staining technique for nucleolar organizer regions (AgNOR) of Ploton et al., as popularized by Crocker, is being widely used for evaluation of nucleolar function, especially in neoplasia. It suffers from limited reliability, background staining, precipitates, and fading of the sections. Factors were identified that affect these problems. The oxidation-reduction level and gelatin used are particularly important. An improved procedure is presented which incorporates pre-reduction of the sections, selection of an optimal gelatin, and post-treatment of the sections to produce a permanent preparation. It is compatible with many fixatives and with other stains used before or after the silver stain.

Two hundred young women had simultaneously prepared cultures for Chlamydia trachomatis and cervical smears; they also completed a questionnaire. Twelve of the chlamydial cultures were positive. There was poor correlation between the culture results and the cytologic morphology or symptoms. On initial blind reading, only 10% of the smears cytologically interpreted as positive were actually positive by culture. Under the most favorable (non-blind) interpretation, only 23% of the smears cytologically interpreted as positive for chlamydial infection were also culture positive. Because of the high incidence of false positives, we conclude that routine cytologic examination of Papanicolaou-stained smears is not an acceptable method for the diagnosis of chlamydial infections of the cervix. Immunoperoxidase staining of duplicate smears did not appear to be a successful replacement for culture.

Immunofluorescent staining was compared to cell culture for the diagnosis of Chlamydia trachomatis infections in the female genital tract. By culture, the incidence in the 496 patients in the study was 12.3%. Immunofluorescence demonstrated organisms in 90% of the culture-positive cases, with a specificity of 99.3%. This method appears to be a successful replacement for culture for general screening.

A specific type of urinary cast has been demonstrated in the urine of patients who have acute pyelonephritis. This cast is characterized by the presence of bacteria in its matrix and appears to be specific for and diagnostic of pyelonephritis. It is easily demonstrated by routine urinalysis.

An endocervical swab, cytologic scraper, and endocervical cytobrush were used to prepare simultaneous full-slide smears for immunofluorescence for the diagnosis of cervical chlamydial infection. The cytobrush produced the best sample, with significantly higher numbers of organisms. Most of the false negative results were obtained with the cytologic scraper. The optimum technique appears to be to use a cytobrush sample; however, a swab should be used with pregnant patients.

A case report of a malignant tumor, presumably paramesonephric in origin, is presented. Although uncommon, malignancies of the cystic structures of the broad ligament have been reported. The embryologic derivations and histologic feature of these tumors--mesonephric, mesothelial and paramesonephric--have been describe extensively, but no primary lesion has been evaluated previously by scanning electron microscopy. A prior laparotomy and biopsy with a diagnosis of a malignant papillary growth, probably paramesonephric, stimulated the examination of fresh tissue by an ETEC Autoscan scanning electron microscope at subsequent definitive, ablative surgery. Although features of cellular dysplasia were noted, there were no specific, unique characteristics of this neoplasm. Since all reported cases have been premenopausal, a hormonal interaction is questioned.

Hyaline urinary casts have been examined primarily by scanning electron microscopy. Their appearance and their transformation with time are described. From this data, the mechanism of their formation and evolution has been deduced. These results permit more accurate identification and assessment of the types of urinary casts present and their significance.

Granular urinary casts were analyzed by scanning electron microscopy and histochemistry. Three types were identified. They appear to have distinctly different origins and significance. Their clinical associations remain to be defined. One type can be misidentified by bright field microscopy. Bacterial casts also can be misidentified as granular casts unless the sediment is examined carefully.

Chlamydial cervicitis is a common and important infection. Diagnostic cytologic criteria have been proposed, but not generally accepted. To better evaluate the cytologic changes, cervical cultures for Chlamydia trachomatis and duplicate cervical smears for Papanicolaou staining and immunofluorescence staining for chlamydial organisms were taken from 496 patients. A total of 61 (12.3%) of the patients had a positive culture for C. trachomatis. By immunofluorescence, the organisms were present as very small extracellular elementary bodies in mucus or as similar bodies in leukocytes; inclusions within epithelial cells were seen in only two cases. The organisms did not stain with the Papanicolaou stain. Chlamydial infection correlated with the degree of inflammation, with the presence of histiocytes and lymphocytes, especially large "transformed" lymphocytes, and with the presence of unidentified short bacteria, which stained red with the Papanicolaou stain. These features predict which patients should be tested more definitively for the presence of chlamydial organisms. However, we found no cytologic criteria that can reliably permit its diagnosis.

A Chlamydia diagnostic service has been established as part of a cytology laboratory, combining prediction of possible infection by routine cytology with definitive testing by immunofluorescence. The first 10 mo of operation have had good clinician acceptance with 527 specimens submitted and 128 reported as positive (24.3%). Routine cytology was more accurate in predicting chlamydial infection than was clinical evaluation (32.8% of cytologically suspected cases were positive versus 20.2% of clinically suspected cases); however, both failed to identify many infected women. The patient selection for testing must be improved since only about 22% of infected women in our population were tested. Nevertheless, the service identified a large number of patients infected with an important sexually transmitted pathogen. Chlamydial diagnosis has become a major component of the laboratory's workload and has been cost-effective.

We present a case in which dramatic anterior midline uptake of 99mTc-pertechnetate simulated a suprasellar tumor in a patient with sarcoid. The brain scan abnormalities proved to represent extensive hypothalamic and basal ganglia involvement by sarcoidosis.

Several recent reports suggest that amyloidosis can be diagnosed by ultrastructural identification of fibrillar proteins in the urinary sediment. However, the authors routinely identified similar fibrils in the urinary sediments of all patients with a wide variety of renal diseases who were producing urinary casts, as well as in those of stressed healthy individuals. They therefore conclude that electron microscopic examination of the urinary sediment alone has little value in the diagnosis of amyloidosis when unaccompanied by chemical or immunologic tests.

Four hundred ninety-three women were examined, had a cervical culture done for Chlamydia trachomatis and completed a questionnaire. Sixty-one, or 12.4%, were positive for Chlamydia on culture. Infected women were more likely to be younger, to be unmarried, to have had more sexual partners, to have had past abnormal cytology, to have spotting or postcoital bleeding, to have a mucoid or purulent cervical discharge and to have signs of cervical inflammation, especially friability. No characteristic finding in the past history, symptoms or physical examination combined sufficient sensitivity and specificity to serve by itself as a basis for selective testing for C trachomatis. It appears that multiple characteristics--including history, symptoms, physical examination and cytologic results--must be utilized to select patients for testing.