The Normal Development of the Lymphoid Mass in the Golden Hamster and its Relationship to the Effects of Thymectomy

A study of lymphoid organ sections and imprints of normal hamsters fromfetal to adult state revealed a sequential pattern of organ structure and growth.The thymus developed an adult structure by 1 week, maximum size at 6 weeks.The mesenteric lymph node had an adult structure by 4 weeks, the spleen by 6weeks, with an accelerated growth of both organs between 6 to 8 weeks. Thegrowth and development of the peripheral lymphoid organs appears to beunder thymic control until the attainment of a "critical peripheral lymphoidmass." This appears capable of functioning independently of thymic control.Thymectomy is effective in producing lymphoid atrophy with resultant immunosuppression and wasting disease only if performed prior to the attainmentof the "critical peripheral lymphoid mass."

Submitted on February 6, 1964 Accepted on July 26, 1964     

BLACK PIGMENT STONE IN A MALE CHILD AGED TWO YEARS AND SEVEN MONTHS

A case of cholelithiasis is reported occurring in a boy aged two years and seven months. The patient presented with biliary colic, and cholecystectomy was performed. Detailed analysis of the stone, including electron-probe studies, showed it to be an example of a polybilirubinate stone, containing also calcium, carbonate, and phosphate, with some sulphur, sodium, and magnesium. There were also traces of chlorine, aluminium, copper, nickel, and manganese.     

Venous and Capillary Hematocrit in Newborn Infants and Placental Transfusion

Hematocrit values were measured on one hundred and eleven sets of capillary (from unwarmed and warmed heels) and venous blood samples obtained simultaneously during the first 5 days of life from 60 full term newborn infants, 40 of which the umbilical cords were clamped late, and 20 clamped early a t the time of birth. In the late clamped infants, the capillary hematocrits showed an initial rise during the first 6 hours of life seemingly due to fluid transudation in the capillary beds, followed by a fall a t 12 to 24 hours of age due to a subsequent fluid reabsorption into the vascular space in response to increasing circulatory demands in the visceral organs. In the early clamped infants, the capillary hematocrits remained stable during the first 6 hours, but a slight decline was observed a t 12 to 24 hours of age. The simultaneously measured venous hematocrits of both late and early clamped infants plotted against age revealed a strikingly similar pattern of alterations. A marked capillary venous hematocrit difference was observed in the late clamped infants and to a much lesser extent in the early clamped infants during the first 5 days of life, with the venous being lower than the capillary values. Warming the heels prior to capillary sampling improves the capillary venous hematocrit correlations in the late clamped infants and the improvement achieved by this procedure increases as the infant becomes older. In the early clamped infants heel warming produces relatively less effects because there was less capillary venous hematocrit discrepancy initially. In infants over 12 hours of age where venipuncture is difficult or inadvisable, capillary blood samples obtained from warmed heels could be used for hematocrit measurements. However, the hematoples do not exactly correspond with the venous values and the approximate venous reading could be estimated by using the regression lines derived from our samples, and their 95% confidence limit could be calculated from the appropriate formulas.     

Allogeneic bone marrow transplantation versus chemotherapy in high-risk childhood acute lymphoblastic leukaemia in first remission

We compared the outcome of children with high-risk acute lymphoblastic leukaemia (HR-ALL) in first complete remission (first CR) treated with chemotherapy (CHEMO) or with allogeneic bone marrow transplantation (BMT) in a multicentre study.   All children treated by the Italian Paediatric Haematology Oncology Association for HR-ALL in first CR between 1986 and 1994 were eligible for the study. 30 children were given BMT at a median of 4 months from first CR, with preparative regimens including total-body irradiation ( n  =25/30). 130 matched controls for BMT patients were identified among 397 HR-ALL CHEMO patients. Matching on main prognostic factors and duration of first CR was adopted to control the selection and time-to-transplant biases. The comparative analysis was based on the results of a stratified Cox model. The estimated hazard ratios of BMT versus CHEMO at 6 months, 1 year and 2 years after CR were 1.38 (CI 0.59–3.24), 0.69 (CI 0.27–1.77) and 0.35 (CI 0.06–1{\raise 5mu ..91), with an overall non-significant difference between the two groups ( P  = 0.34). With a median follow-up of 4 years, the disease-free survival was 58.5% (SE 9.3) in the BMT group and 47.7% (SE 4.8) in the CHEMO group, at 4 years from CR. Non-leukaemic death occurred in 4% of CHEMO and 10% of BMT patients. In the BMT group the estimated cumulative incidence of relapse at 1.5 years from CR was 31.5% (SE 8.8) and did not change thereafter, whereas in the CHEMO group the corresponding figure was 29.2% (SE 4.1) and the incidence continued to increase thereafter (48.2% (SE 4.8) at 4 years from CR).   The results of this study suggest that, with respect to the CHEMO group, the higher risk of early failure in the BMT group is outweighed by the lower risk of relapse after 1 year. Results prompt the need for a prospective study, in order to demonstrate the likely advantage of BMT in HR childhood ALL in first CR.