Expression of Escherichia coli fol alleles in Salmonella typhimurium.

Studies of the expression of Escherichia coli fol alleles in Salmonella typhimurium indicated that fol regulatory functions are highly conserved between these bacterial species.     

Theory of inbreeding and covariances between relatives under full-sib mating in diploids.

A generation matrix theory of full-sib mating is developed in which 13 mating "classes" are distinguished according to identity of genes in individuals mated and identity of genotypes as belonging to homozygous, parental, or offspring sets. The 13 times 13 matrix reveals some properties of the full-sib mating system not shown by previous work. The eigenvalues and a set of eigenvectors for the generation matrix, and the general solution for the frequencies of mating classes among descendants of an original mating of genotypes ab times cd, are given. The genotypic array of descendants in an arbitrary generation is also given. A new formula is derived for the coefficient of inbreeding in generation n + m in terms of coefficients of inbreeding in earlier generations. An algorithm is presented for calculating the probability of a given situation of identity of alleles carried by two individuals given only the indices of their own respective generations and the generation of their most recent common ancestor. The application of such probabilities to obtaining covariances between relatives in a full-sib mating system, under the assumptions of independence and non-interaction among loci, is illustrated. All results are shown to agree with previous work in special cases. All possible full sib, generation n - 1 parent-generation n + m offspring, and generation n uncle-generation n + m nephew covariances for 1 less than n + m less than or equal to 8 are obtained using the given algorithm.     

An apparatus for anesthetizing small laboratory animals.

A simple apparatus was designed for simultaneous general anesthesia of a number of small laboratory animals with spontaneous respiration. Anesthesia is consistent over many hr. The apparatus consists of an oxygen tank and vaporizer, a glass distribution bottle, and a non-return circuit of separate inspiratory and expiratory valves for each animal. The equipment is inexpensive to construct and can be rapidly adjusted for exact control of gas flow and anesthetic depth.     

H-rosette formation in T-cell-proliferative diseases.

In health up to 6% of human lymphocytes will form rosettes with homologous group O rhesus-negative erythrocytes (H rosettes). Increased numbers of H rosettes were found in T-cell-proliferative diseases-- namely, infectious mononucleosis, Sézary''s syndrome, and T-cell leukaemia. H-rosette formation is thus a marker for a subpopulation of T lymphocytes, and this easily performed test of T-cell activation may have clinical value in characterising changes in blood lymphocyte populations in disease.     

EMERGENCY OPERATIONS IN THE NEWBORN

With the present-day development and understanding of anesthetic methods, fluid and electrolyte therapy, antibiotic medications and pediatric care, many congenital anomalies once uniformly fatal are now being successfully treated by emergency operations in the neonatal period. The eight most common of these which demand emergency operation in the immediate postnatal period are esophageal atresia and tracheoesophageal fistula, diaphragmatic hernia with dislocation of the abdominal viscera into the chest, malrotation of the intestine with obstruction, intestinal atresia, meconium ileus, imperforate anus, omphalocele and myelomeningocele.Although infants born with any of these serious problems often are born prematurely and often have more than one congenital anomaly, survival rates in the surgical treatment of these conditions are steadily improving. Early diagnosis and prompt treatment are the most important factors in the continued improvement of these survival rates.