The early detection of cervical cancer: a critical appraisal of diagnostic procedures

Exfoliative cytology is the most effective single method used in the early detection of uterine cervix cancer. It will detect about 90 percent of preclinical carcinomas, but when combined with colposcopy, the detection rate approaches 100 percent. For confirmation of the cytological diagnoses in cases of preclinical carcinoma, sharp cold-knife conization is the major procedure used. It is therapeutic as well as diagnostic. Single punch biopsy is used mainly for confirming clinically evident cervical cancers. Multiple punch biopsies are of value in colposcopic work when used in combination with the Schiller's iodine test. This is particularly important in pregnancy when cervical conization carry certain definite risks. The exceedingly high incidence of uterine cervix cancer in Jamaica could be effectively controlled by rational utilization of these diagnostic modalities, particularly when there is close collaboration between gynaecologists, cytologists and pathologists (AU)

The methylene blue reduction test: evaluation of a screening method for glucose-6-phosphate dehydrogenase deficiency

Male and female neonates, children and adults, and patients with hemolytic anemia, in whom subnormal erythrocye glucose-6-phosphate dehydrogenase deficiency was demonstrated on spectrophotometric assay, were all detected using the methylene blue reduction screening test. This finding and the results of mixing experiments suggested that it is as sensitive as the assay. Offering advantages over the screening tests, it is useful for surveys and for routine laboratory work. (AU)

Microscopic and enzyme histochemical studies on the liver and kidney of rats treated with fulvine, the toxic alkaloidal constituent of crotalaria fulva

Histochemical changes in the liver of rats, treated with the pyrrolizidine alkaloidal constituent of Crotalaria fulva, indicated primarily damage of the hepatic parenchymal cells. The observed differences in activity of enzymes suggested functional inpairment of the cell membrane, mitochondria, endoplasmatic reticulum, and lysosomes in the liver cells. In large doses, fulvine produced a hyaline droplet degeneration in the epithelium of the proximal convoluted tubules of the kidney. Stability of the mitochondrial and changes in activity of the lysosomal enzymes would imply a functional adaptation, rather than primary damage of the epithelium.(AU)

A histochemical investigation of the concept of placental insufficiency

Using histochemical methods, the distribution and quantities of 10 enzymes were studied in 91 placentae representing normal and various types of abnormal pregnancies. It was concluded that the increasing concentration of alkaline phosphatase and glucose-6-phosphatase, and the decreasing concentration of acid phosphatase in the trophoblast are probably features of placental aging, and may also be associated with placental insufficiency (Summary)

A histochemical investigation of the concept of placental insufficiency

This thesis is an account of some histochemical characteristics of placental tissue and their relationships to ageing and possibly to conditions associated with placental insufficiency. The introduction is a review of the clinical, experimental, and anatomical evidence for the concept of placental insufficiency. Using histochemical methods, the distribution and quantities of 10 enzymes were studied in 91 placentae representing normal and various types of abnormal pregnancies. Alkaline phosphatase and glucose - 6 - phosphatase showed a rising concentration in the trophoblast in late pregnancy. This rise was more marked and appeared earlier in placentae from patients with severe pre-eclampsia. Placentae from patients with pre-existing hypertension did not appear to differ from normal ones of similar periods of gestation. Acid phosphatase was localised in the trophoblast and decreased in amount in late pregnancy. This decrease was more marked, and occurred earlier in placentae from cases of severe pre-eclampsia and pre-existing hypertension than in normal placentae. Lactate dehydrogenase; malate dehydrogenase; di-phosphopyridine nucleotide diaphorase(D.P.N.D.); alpha-glycerophosphate dehydrogenase; and glucose - 6 - phosphate dehydrogenase were all present in the trophoblast throughout pregnancy without showing any apparent change in concentration. Succinate dehydrogenase could not be found in the trophoblast at any time, occurring only in the decidual cells of the placental bed. Leucine amino-peptidase showed a patchy distribution throughout the connective tissue stroma of the chorionic villi and within the walls of the larger blood vessels. It was concluded that the increasing concentration of alkaline phosphatase and glucose - 6 - phosphatase, and the decreasing concentration of acid phosphatase in the trophoblast are probably features of placental ageing, and may also be associated with placental insufficiency (Summary)

Senescence in the placenta: an enzyme histochemical study

There is a variety of experimental and clinical evidence available suggesting that the placenta undergoes age changes during the last 4-6 weeks of pregnancy, which are associated with corresponding reduction in its functional capacity. Although the anatomical criteria for ageing in the placenta are not by any means universally accepted, a general pattern is beginning to emerge. During the last trimester, the sycytiotrophoblast appears to undergo progressive degeneration so that the cytoplasm becomes gradually thinner, and the nuclei are displaced into small clusters referred to as "syncytial knots". Parallel with this change, there is occasionally a proliferation of the cytotrophoblast which has usually undergone gradual reduction in amount during the middle trimester, but appears to regenerate under the stimulus of anoxia. The connective tissue stroma of the villi becomes progressively denser and more collagenous, occasionally undergoing hyaline change. The vessels of the stroma meanwhile, tend to undergo narrowing of their lumen. The microscopical changes which have been described, are of a fairly gross nature, and they may represent the end results of a progressive degenerative process. In order to determine the earliest changes occurring in the villi of the placenta, which it was assumed would probably be of a metabolic nature, an enzyme histochemical study was undertaken. Multiple biopsies were obtained from 92 placentas representing various normal and abnormal pregnancies at different stages of gestation. The biopsies obtained from each placenta were made into composite blocks and snap-frozen using a dry ice-acetone mixture. These composite blocks were then stored at minus 20 degrees C. until processed. Eight micron sections of each composite block were obtained by cutting in a Pears ctyostat. The results can be briefly summarised as follows: (1) Alkaline Phosphatase and glucose-6-phosphatase showed a rising concentration in the trophoblast with advancing pregnancy. (2) Acid Phosphatase within the trophoblast showed an apparent decrease in amount in late pregnancy. (3) Lactate Dehydrogenase; Malate Dehydrogenase; Alpha-glycero-phosphate Dehydrogenase; and glucose-6-Phosphate Dehydrogenase were present in the trophoblast throughout pregnancy without showing any apparent change in concentration. (4) Succinate Dehydrogenase could not be found in the trophoblast at any time, occurring only in the decidua underlying the placental bed. Leucine Amino-peptidase showed a patchy distribution throughout the connective tissue stroma of the chorionic villi and within the walls of the larger blood vessels. On the basis of these findings, it is suggested that a rising content of alkaline phosphatase and glucose-6-phosphatase, associated with a falling concentration of acid phosphatase, constitute histochemical criteria on which a diagnosis of placental senescence can be based(AU)

Placental insufficiency investigated by enzyme histochemistry

The enzyme histochemistry of 92 placentae representing various normal and abnormal pregnancies at different stages of gestation was studied. Alkaline phosphatase and glucose-6-phosphatase showed a rising concentration in the trophoblast with advancing pregnancy. Acid phospatase within the trophoblast showed an apparent tendency to decrease in amount in late pregnancy. Lactate dehydrogenase, malate dehydrogenase, alpha-glycero-phosphate dehydrogenase and glucose-6-phosphate dehydrogenase were present in the trophoblast throughout pregnancy without any apparent change in concentration. Succinate dehydrogenase could not be found in the trophoblast at any time, occurring only in the decidua underlying the placental bed. Leucine amino-peptidase showed a patchy distribution throughout the connective tissue stroma of the chorionic villi and within the walls of the larger blood vessels. It was suggested that a high concentration of alkaline phosphatase and glucose-6 phosphatase associated with a low concentration of acid phosphatase constituted the histochemical parameters of placental insufficiency (AU)