Assignment of the functional gene for human adrenodoxin to chromosome 11q13----qter and of adrenodoxin pseudogenes to chromosome 20cen----q13.1

Adrenodoxin is a small iron/sulfur protein serving as an electron-transport intermediate for all mitochondrial forms of cytochrome P450. Southern blots of normal genomic DNA cleaved with six restriction endonucleases probed with full-length human adrenodoxin cDNA revealed complex patterns indicating the presence of multiple adrenodoxin genes. Southern blots of DNA from a panel of mouse/human somatic cell hybrids identified cross-hybridizing adrenodoxin DNA in two loci, chromosome 11q13----qter and chromosome 20cen----q13.1. Examination of adrenodoxin clones from a genomic DNA library in phage lambda revealed some clones bearing gene fragments interrupted by introns and other clones bearing processed pseudogenes. By probing the mouse/human hybrids with unique intronic DNA and by correlating restriction maps of the phage clones with that of uncloned genomic DNA, we show that the authentic transcribed adrenodoxin gene lies on chromosome 11, while pseudogenes lie on chromosome 20.

Computed tomography of a meniscal cyst

A meniscal cyst of the knee is a rare lesion, and a palpable large meniscal cyst is even more rare. This article suggests that CT scan demonstrates clear location, size, contents, and connection of the cyst with meniscus and peripheral tissue. By a combination of arthrography and CT scan, detection of the cysts in zone 3 (parameniscal area) is possible with ample demonstration of whether the cyst is associated with a meniscal tear. This provides a guideline in determining the treatment of the lesion.

Marrow culture studies in adult acute myeloid leukemia at diagnosis and during complete remission

We used the human placental conditioned medium stimulated single layer agar culture technique to study the in vitro growth of marrow cells from 62 adult patients with acute myeloid leukemia (AML). Bone marrow cells were cultured from 50 patients at the time of initial diagnosis, 19 patients in early remission and 20 patients during their full complete remission. Marrow cultures from untreated patients exhibited heterogeneous growth patterns ranging from complete growth failure to excessive microcluster formation. We classified the growth patterns into 4 groups: (1) Gr I: normal growth, (2) Gr II: no growth, (3) Gr III: decreased growth, (4) Gr IV: excessive growth of microclusters. At presentation, none had Gr I growth; Gr II growth was observed in 23; Gr III in 14 and Gr IV in 13. A predominance of no growth were seen in M1 and M3 subtypes, while Gr IV growth was more commonly observed in M2 or M4 subtype. We were unable to correlate the culture findings with age or white cell count. The present results not only indicated that AML at diagnosis was characterized by abnormal granulopoiesis but also demonstrated that leukemic progenitor cells were heterogeneous with different capacities to express their proliferating potential in vitro. Except few with decreased growth, the growth characteristics generally returned to normal with successful remission induction. Both Gr II and Gr IV growth patterns were not observed either in early remission or during full complete remission.

Testicular gonadal stromal (Sertoli cell) tumor

Eighty-one cases of testicular gonadal stromal tumor have been reported in the literature. An additional case is herein reported. The pathologic, immunohistologic, and histogenetic aspects are presented.

Wavelength and temperature dependence of RAPD aser detectors

Wavelength and temperature-dependent characteristics of silicon reach-through avalanche photodiodes (RAPD) are studied using the modified Baraff's theory. The temperature and wavelength regions discussed are 100-500 K and 0.655-1.06 microm, respectively, for Si photodetectors. The effects of breakdown voltage, depletion region width, and efficiency on the avalanche region width are widely studied. Both n(+) (front) side and p(+) (back) side illumination are also considered. The noise equivalent power is significantly reduced with light incident on the p(+) surface with little sacrifice of efficiency. An RAPD structure is proposed in which the direction of radiation incidence causes photogeneration to precede avalanche multiplication reducing the multiplication noise substantially. This result should be useful in the design of RAPD laser detectors.

Characteristics of P-I-N laser detectors: their dependence on wavelength and temperature

Wavelength and temperature-dependent characteristics of silicon P-I-N laser detectors are studied using the modified Baraff theory. Both the electron or hole injection effect and photogeneration effect are considered in the calculation of the power spectral density of multiplication noise and efficiencies. The results thus obtained are compared with previous papers where the photogeneration effect was neglected.