Force systems from orthodontic appliances: an analytical and experimental comparison.

Experimental data is compared with the simulated displacements from a computer program for the clinical activations of two separate orthodontic appliances undergoing a total of four separate loading conditions. Good agreement is shown over the entire range of activation. Suggestions for future strengthening of both the analytical and the experimental methods are given.

Bone marrow and lymph node findings in a fatal case of Kawasaki's disease.

Since the initial description in 1967, the clinical and laboratory features of Kawasaki's disease (KD) have been well documented. We studied a patient with KD who recovered from the acute phase of the disease, but who subsequently died at home from coronary arteritis. We describe this patient because of bone marrow and lymph node findings that have previously received little attention in the English-language literature.

Androgens regulate mitochondrial cytochrome c oxidase and lysosomal hydrolases in mouse skeletal muscle.

The gastrocnemius, a fast-twitch white muscle, and the soleus, a slow-twitch red muscle, were studied in A/J mice. The specific activities of the lysosomal hydrolases, beta-D-glucuronidase, hexosaminidase, beta-D-galactosidase and arylsulphatase, the inner-mitochondrial-membrane enzyme cytochrome c oxidase, and the outer-mitochondrial-membrane enzyme monoamine oxidase, were greater in the soleus than in the gastrocnemius. The specific activities of the lysosomal hydrolases and cytochrome c oxidase in the gastrocnemius and soleus were substantially higher in male mice than in female mice.

Switching of the nonallelic forms of fetal hemoglobin during late gestation.

The gamma chains of human fetal hemoglobin occur in two nonallelic forms, designated G gamma and A gamma, which differ from one another in having either glycine or alanine as their 136th residue respectively. In newborns, G gamma comprises about 75% of the total gamma chains, while in adults, G gamma comprises about 40% of the total gamma chains. The timing of the switching events that lead to the alteration of the rates of production of G gamma and A gamma are still unknown.

Testosterone-mediated sexual dimorphism of mitochondria and lysosomes in mouse kidney proximal tubules.

In kidney proximal tubules of male mice the mitochondria are larger and more electron-lucent, autophagic vacuoles and lysosomes (predominantly myeloid bodies) more numerous and voluminous, and exocytosed intraluminal myeloid bodies more common than in females. Males also have higher kidney activities of mitochondrial cytochrome c oxidase and lysosomal hydrolases, and excrete larger quantities of hydrolases and protein in the urine. Orchiectomy evokes the feminine pattern whereas testosterone administration induces the male pattern.

Edge coupling of a GaAlAs DH laser diode to a planar Ti:LiNbO(3) waveguide.

The problem of edge coupling a double-heterostructure GaAlAs laser diode to a planar titanium indiffused LiNbO(3) waveguide has been studied both experimentally and theoretically. Alignment sensitivities (3-dB points) have been measured and found to be ~15 and 1 microm in the longitudinal and transverse directions, respectively. The dependence of the coupling efficiency on misalignments has been found to be in good agreement with the predictions of a simple Gaussian coupling model.

Unequal crossing-over: a common basis of single alpha-globin genes in Asians and American blacks with hemoglobin-H disease.

The alpha-globin genes of five black Americans, two Chinese, and five Filipinos with HbH disease (an alpha-thalassemia state in which there is a single functional alpha gene) were analyzed by restriction endonuclease techniques. All subjects were found to have one chromosome 16, lacking both alpha genes, and another containing a single alpha gene (--/-alpha). Restriction endonuclease patterns of the DNA obtained from all 12 subjects were identical and compatible with unequal crossing-over as the mechanism of origin of the single alpha gene in these individuals.

Alpha-thalassemia in blacks is due to gene deletion.

We used molecular hybridization to test if alpha-thalassemia is due to gene deletion in the black. In 10 families with clinically well-defined alpha-thalassemia-1 (alpha-thal-1), hydribization of alpha-globin cDNA was reduced to the same level as that found in Asians with alpha-thal-1, where two of the four normally present alpha-globin genes are deleted. A black child with hemoglobin H (Hb H) disease also has three globin genes deleted, as do Asian patients with Hb H disease.

Immune suppression of erythropoiesis in transient erythroblastopenia of childhood.

Serum and IgG from four children with transient erythroblastopenia of childhood (TEC) was tested to see what effect it would have on development of erythroid colonies from bone marrow mononuclear cells. Serum and IgG specimens obtained at the time of diagnosis uniformly suppressed erythroid colony development from CFU-E. Washed bone marrow mononuclear cells from a child with TEC failed to grow in the presence of his own serum, but grew normally in the presence of isologous serum.

[Molecular forms of acetylcholinesterase in the chicken ciliary ganglion; changes after denervation, axotomy and double section].

Four main molecular forms of acetylcholinesterase (AChE), with sedimentation coefficients of 5, 7.5, 11.5 and 20 S, are found in Chicken ciliary ganglion.

Platelet-associated immunoglobulin G in childhood idiopathic thrombocytopenic purpura.

Childhood ITP is an acquired hemorrhagic disorder with a heterogeneous clinical course. We measured PAIgG levels in 20 children with ITP (7 acute, 13 chronic). Both groups had significantly greater PAIgG values than age-matched normal subjects and thrombocytopenic controls (P less than 0.

Heterogeneity of fetal hemoglobin in severe alpha-thalassemia.

The heterogeneity of residue 136 of the gamma-chain of human hemoglobin has been determined for a patient afflicted with severe alpha-thalassemia. Separation of the cord blood sample into the various constituent hemoglobins A, F, FI and Bart's were done on a column packed with DEAE Sephadex. The amount of glycine or alanine at position 136 was determined for hemoglobins F, FI and Bart's.

Prenatal diagnosis of hemoglobin H disease.

Hemoglobin H disease was diagnosed prior to the twenty-second week of gestation in a pregnancy at risk for homozygous alpha-thalassemia using the technique of DNA-DNA hybridization. Fetal DNA was obtained from amniotic fluid fibroblasts obtained during the thirteenth week of gestation and grown in culture. The fetal fibroblast DNA was hybridized to radioactive alpha-globin cDNA.