LEUKAEMIC INVOLVEMENT OF CENTRAL NERVOUS SYSTEM

Eighty two patients of leukaemia consisting of 25 cases of acute lymphocytic leukaemia, 38 cases of acute myeloid leukaemia, 14 cases of chronic myeloid leukaemia and 5 cases of chronic lymphocytic leukaemia were evaluated for central nervous system (CNS) involvement. Speech disorders, cranial nerve palsies, encephalopathy, ataxia, intracranial haemorrhage, peripheral neuropathy and spinal cord involvement were the main neurological findings detected in 23 (28.1%) cases. All except one were subjected to autopsy after death. Leukaemic infiltrations (36.6%) and intracranial haemorrhage (26.8%) were the prominent CNS autopsy findings. In addition, demyelination with astrocytosis (9.7%) and gliosis (2.4%) were seen. In all, 45 (54.9%) of the patients showed CNS involvement at autopsy. Thus a large number of CNS lesions were missed clinically and detected only on autopsy.KEY WORDS: Intracranial haemorrhage, Leukemia, Metastasis     

PRELIMINARY STUDY OF HOW ALCOHOL CONSUMPTION DURING PREGNANCY AFFECTS IMMUNE COMPONENTS IN BREAST MILK AND BLOOD OF POSTPARTUM WOMEN

Human milk has been shown to contain numerous immune componentsthat can potentially protect the infant during the period beforeits own immune system is completely developed. Alcohol consumptionin both experimental animals and humans has been associatedwith alterations to a number of immune parameters. We have investigatedthe possibility that alcohol consumption during pregnancy alterscertain immune components in day 3 postpartum breast milk andperipheral blood of women. Our study group consisted of 10 alcoholicbeverage drinkers (moderate to heavy, most of whom smoked a1/2-1 pack of cigarettes per day), 15 non-drinking/non-smokingcontrols, and 10 non-drinking/smokers (1/2-1 pack per day) controls.The immune parameters measured in these otherwise healthy womenwere: (1) percentage and absolute number of the various subsetsof leukocytes; (2) percentage of T cells, B cells, T helperand cytotoxic/suppressors subsets, and natural killer cells;(3) levels of the cytokines IL-6, IL-8 and TNF-; (4) levelsof IgA in milk and IgG in serum. Milk from the alcohol groupcontained an elevated amount of IL-8 as compared with milk fromnon-smoker controls; however, it did not differ statisticallyfrom that of the smoker controls. Blood from the alcohol groupshowed an increased level of IL-8 when compared with that fromboth smoker and non-smoker controls. The total number of leukocytesin milk was elevated in milk from the alcohol group as comparedto both the smoker and non-smoker control groups. In the leukocytecomponent of milk, neutrophils predominate and are responsiblefor the elevation in total number of cells, as both lymphocyteand macrophage populations did not differ from those of thecontrols. For lymphocytes, B cells were also increased in bloodof the smokers as compared with the alcohol and non-smoker controls.There were no statistical differences in any of the other immuneparameters tested among the three groups. The present studyfound that alcohol consumption during pregnancy could modulatethe production of IL-8 and infiltration of certain leukocytesin milk and blood of postpartum women. Some of these alterationswere also evident in the smoker controls and thus could notbe attributed to alcohol consumption alone.     

Mathematical and Biostatistical Methods for Designing and Analyzing Complex Interactions

Mathematical and Biostatistical Methods for Designing and AnalyzingComplex Chemical Interactions. CARTER, W.H., Jr., AND CARCHMAN,R.A. (1988). Fundam Appl. Toxicol 10, 590–595. In thispresentation, statistical methods for designing and analyzingexperiments evaluating a mixture of drugs/chemicals are discussed.These methods are promising in that they are not limited bythe number of interacting agents in the combination. Severalexamples are given and a discussion of the results follows.     

Development of a Testing Battery to Assess Chemical-Induced Immunotoxicity: National Toxicology Program's Guidelines for Immunotoxicity Evaluation in Mice

Development of a Testing Battery to Assess Chemical-InducedImmunotoxicity: National Toxicology Program's Guidelines forImmunotoxicity Evaluation in Mice. Luster, M. I., Munson, A.E., Thomas, P. T., Holsapple, M. P., Fenters, J. D., White,K. L., Jr., Lauer, L. D., Germolec, D. R., Rosenthal, G. J.,and Dean, J. H. (1988). Fundam. Appl. Toxicol..     

A Canine Model of Torsades de Pointes

Although quinidine has been reported to induce QT interval prolongation and torsades de pointes clinically, the only experimental model currently available for quinidine-induced torsades de pointes requires the concurrent use of ischemia, reperfusion and cardiac pacing of the isolated, perfused heart. Our purpose in this study was to determine the circumstances under which quinidine might elicit torsades de pointes consistently in the intact dog. We found that maintenance of therapeutic plasma quinidine concentrations, alone, did not induce the arrhythmia. Rather, arrhythmia induction required the additional application of aconitine, which induces early afterdepolarizations and triggered activity. When aconitine was applied to two epicardial sites in dogs having quinidine-induced QT interval prolongation greater than 10%, torsades de pointes occurred in 80% of instances. When QT prolongation was less than 10%, aconitine-induced torsades de pointes was seen in only 21% of animals. Our results suggest that in a previously healthy heart quinidine-induced QT prolongation is, itself, insufficient to induce torsades de pointes consistently, and two independent sites of ectopic activity are needed as well. The ectopic foci appear to modulate one another's impulse initiation or activation sequence, thereby giving rise to the classical "twisting of the points" associated with the arrhythmia.     

β-defensins and the epididymis: contrasting influences of prenatal,postnatal, and adult scenarios

β-defensins are components of host defense, with antimicrobial and pleiotropic immuno-modulatory properties. Research over the last 15 years has demonstrated abundant expression of a variety of β-defensins in the postnatal epididymis of different species. A gradient of region- and cell-specific expression of these proteins is observed in the epithelium of the postnatal epididymis. Their secretion into the luminal fluid and binding to spermatozoa as they travel along the epididymis has suggested their involvement in reproduction-specific tasks. Therefore, continuous attention has been given to various β-defensins for their role in sperm function and fertility. Although β-defensins are largely dependent on androgens, the underlying mechanisms regulating their expression and function in the epididymis are not well understood. Recent investigation has pointed out to a new and interesting scenario where β-defensins emerge with a different expression pattern in the Wolffian duct, the embryonic precursor of the epididymis, as opposed to the adult epididymis, thereby redefining the concept concerning the multifunctional roles of β-defensins in the developing epididymis. In this review, we summarize some current views of β-defensins in the epididymis highlighting our most recent data and speculations on their role in the developing epididymis during the prenatal-to-postnatal transition, bringing attention to the many unanswered questions in this research area that may contribute to a better understanding of epididymal biology and male fertility.     

Bacterial penetration through temporary restorative materials in root-canal-treated teeth in vitro

Seventy extracted single-rooted mandibular premolars were used in this study to determine the length of time needed for bacteria present in natural human saliva to penetrate through three commonly used temporary restorative materials and through the entire root canal system obturated with the lateral condensation technique. Five intact teeth with no decay were used in the negative control group and five teeth with extensive decay in communication with the canal, in the positive control group. The 60 teeth used in the experimental group were divided into three groups. In Group 1, the access cavities of 20 teeth were temporarily restored with gutta percha, in Group 2 with IRM and in Group 3 with Cavit-G. All 70 teeth were mounted individually where the crown was placed in contact with human saliva. All five teeth in the positive control group caused broth turbidity within 24 h. In contrast, broth in the negative control group remained clear throughout the entire experimental period. In the experimental group, the average time for broth contamination of access cavities closed with gutta percha, IRM and Cavit-G was 7.85, 12.95 and 9.80 days, respectively. The Kruskal-Wallis nonparametric test showed significant differences among the groups, while the multiple comparison test showed that the IRM group was statistically better than the gutta percha group when the average lengths of time for contamination were compared ( P < 0.05).     

Bacterial Contamination of Tube-Feeding Formulas

Bacterial cultures were made on tube-feeding formulas provided to 35 unselected adult patients on termination of the infusion. Bacteria were counted and identified using routine procedures. Formulas were classified as nonmanipulated, manipulated, or locally prepared. Medical records were reviewed to determine if diarrhea was present during the period that included 2 days on either side of the sampling day. A significant association was observed between the extent of bacterial contamination and the presence of diarrhea (p = 0.027). Locally prepared and manipulated formulas contained a significantly greater number of organisms when compared to nonmanipulated formulas (χ² = 17.81, p < 0.001). Counts for two baseline and four termination cultures on locally prepared formulas exceeded the acceptable limit for coliform organisms in pasteurized milk according to public health standards. Eight additional cultures on commercial feeding formulas which were presumably sterile initially, exceeded these standards at the end of the administration period. Thus 12 of 35 formulas (34%) would not meet public health standards applicable to pasteurized milk. Use of sterile nonmanipulated formulas in a closed administration set is recommended, along with routine, periodic bacteriologic surveillance of enteral feeding programs. (Journal of Parenteral and Enteral Nutrition 8:673–678, 1984)     

Subcutaneous Fat Necrosis of the Newborn

Subcutaneous fat necrosis of the newborn (SFNN) developed in a 1-week-old black boy. His mother had received numerous medications for eclampsia. Birth was by Caesarean section and complicated by meconium aspiration. There were numerous nodules over the back, buttocks and extremities that yielded a caseous-like material. Microscopically, these nodules showed crystallization and necrosis of the fat. Hypoglycemia, pneumonia, oliguria, thrombocytopenia, seizures and urinary infection were associated with the cutaneous problem and led to a fatal outcome 2 weeks after birth.