Clinical Assessment of Gestational Age

There is disagreement among authors as to what criteria are most reliable in assessing postnatal fetal age. A comparison–for objectivity, accuracy, and frequency of use– of specific criteria was made using three independent examiners at different educational levels: a second-year medical student, a perinatal nurse practitioner, and a pediatrics resident. It was shown that trained examiners develop favorite criteria which differ among examiners and thus sacrifice accuracy; however, accurate assessment of fetal age can be accomplished by an examiner with minimum clinical knowledge.     

Hemolytic property of some carbohydrases; their possible role in red cell destruction

-glucuronidase, in concentration above the normal level in the blood, hemolyzed human red blood cells after a latent period of 10 to 12 hours. Erythrocytessensitized by specific antibodies are lysed in the presence of -glucuronidase inphysiologic concentrations (approximately 200 Fishman units per 100 ml. ofserum). Other enzymes, such as hyaluronidase and lysozyme, are hemolytic also.Similarity between these enzymes and the lysins found in pre-incubated tissueextracts is pointed out. It is suggested that -glucuronidase and hyaluronidaseplay some role in the destruction of red blood cells under certain pathologic conditions. The inhibition of the lytic action of -glucuronidase by D-glucosaccharicacid and by small concentration of silver nitrate is shown. Inhibitors of -glucuronidase lysis could be of some value in the treatment of some hemolyticdisorders.

Submitted on October 8, 1954 Accepted on May 30, 1955     

Suppression of Post-vasectomy Cytotoxic Sperm Antibody Formation in Rats by a Short-term Pretreatment With Cyclosporine

ABSTRACT: The effect of a short pulse therapy with cyclosporine on the production of vasectomy-induced cytotoxic sperm antibodies was studied in Lewis rats. Cyclosporine at a dose of 10 mg/kg was administered once daily for 7 days before and 7 days after vasectomy (group A), for 7 days before vasectomy (group B), and for 7 days after vasectomy (group C). Ten rats were studied in each group for a period of 5 weeks. Ten rats were vasectomized and untreated with cyclosporine (group U). All animals in this group developed high titers of cytotoxic sperm antibodies at the end of the first week after vasectomy (primary antibody response). In contrast, all the treated rats of groups A, B, and C had a normal range of sperm antibody titers. By the third week, six of nine rats in the post-treated group C had significant cytotoxic sperm antibody titers, while the other groups had normal antibody titers. In the fourth week, all the rats of groups A and B continued to have normal sperm antibody titers of ≤16, while most animals in groups C (78%) and U (63%) had significant cytotoxic sperm antibody titers. It is concluded that prevasectomy treatment with cyclosporine may significantly reduce or delay the production of cytotoxic sperm antibodies in Lewis rats.     

Humoral and cell-mediated immunity to MSP3 peptides in adults immunized with MSP3 in malaria endemic area, Burkina Faso

We performed a single-blind, randomized phase 1 trial of the long synthetic peptide (LSP) of merozoite surface protein-3 (MSP3) in adults living in Burkina Faso. Thirty eligible volunteers were randomized to receive either the MSP3-LSP candidate vaccine or tetanus toxoid vaccine as a control. A dose of each vaccine was administered on days 0, 28 and 112 and the vaccine was formulated with aluminium hydroxide. Humoral immune responses were assessed by ELISA at days 0, 28, 56, 112, 140, 252 and 365 and cell-mediated immune responses by lymphoproliferation assay and by ELISA on days 0, 56 and 140. IgG responses to four peptides of MSP3 were similar in both vaccine groups. Higher IgG concentrations were recorded after the beginning of malaria high transmission season in both vaccine groups. The lymphocyte proliferation and the production of IFN-γ in response to stimulation with the four overlapping peptides increased following vaccination in the MSP3-LSP vaccine group, but did not change appreciably in the control group. In contrast to natural infection, MSP3-LSP did not boost humoral responses to the four overlapping peptides of MSP3 to any detectable degree in our semi-immune adult. MSP3-LSP may be more immunogenic in young children with little or no acquired immunity.