Myectomy versus myotomy as an adjunct to membranectomy in the surgical repair of discrete and tunnel subaortic stenosis

The results of membranectomy and deep myectomy in the left ventricular outflow tract were compared to those of membranectomy and myotomy in 42 patients who underwent surgical repair of discrete and tunnel subaortic stenosis. Fifteen consecutive patients (Group A) underwent membranectomy and myotomy, and 27 consecutive patients (Group B) underwent membranectomy and myectomy. Two patients of Group A and nine of Group B had tunnel subaortic stenosis. The preoperative mean (+/- standard deviation) peak systolic gradients across the left ventricular outflow tract in patients with discrete subaortic stenosis types I and II were 64 +/- 29 mm Hg in Group A and 52 +/- 3 mm Hg in Group B (p = not significant). In the patients with tunnel subaortic stenosis the preoperative mean gradients were 97 +/- 74 mm Hg in Group A and 73 +/- 26 mm Hg in Group B (p = not significant). In patients with discrete subaortic stenosis types I and II, postoperative catheterization at a mean follow-up of 21 months revealed residual mean gradients of 29 +/- 24 mm Hg in Group A and 10 +/- 13 mm Hg in Group B (p less than 0.01). In the patients with tunnel subaortic stenosis, the postoperative mean gradients were 25 +/- 7 and 30 +/- 30 mm Hg in Groups A and B, respectively (p = not significant). We conclude that in the surgical management of discrete subaortic stenosis types I and II, deep myectomy (in addition to membranectomy) produces better relief of the left ventricular outflow obstruction than do membranectomy and myotomy. In patients with tunnel subaortic stenosis myectomy is less effective than in the non-tunnel type but still produces acceptable results and may delay radical procedures to a later age.     

Sequence-specific DNA binding of individual cut repeats of the human CCAAT displacement/cut homeodomain protein.

CCAAT displacement protein (CDP), a nuclear protein of 180-190 kDa, contains a triplicated motif, the cut domain, similar (80-90% conserved) to three repeats of 60-65 amino acids first identified in Drosophila cut, a homeo-domain protein involved in cell-fate decisions in development. Cut repeats bind DNA and exhibit subtle differences in target-site recognition. DNA sequences specifically bound by cut repeats were isolated by PCR-mediated DNA target-site selection. Sequences selected for cut repeat 2 and 3 (CR2 and CR3) binding are A+T-rich and favor an ATA motif with similar, but not identical, flanking base preferences. CR2 and CR3 discriminate among similar target sequences. CR1, which is more divergent from CR2 and CR3, displays the most restricted pattern of DNA sequence recognition. Methylation interference analysis demonstrates different protein-DNA contacts for CR1 and CR3 binding to a target sequence. Thus, CDP/cut is a complex protein whose DNA-binding properties reflect the combinatorial interaction of four domains (three cut repeats and one homeodomain) with target DNA sequences.     

Frequent ongoing T-cell receptor rearrangements in childhood B- precursor acute lymphoblastic leukemia: implications for monitoring minimal residual disease

Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.     

Short-term enzyme replacement in the murine model of Sanfilippo syndrome type B

The Sanfilippo syndrome type B (MPS III B) is an autosomal recessive disease caused by deficiency of alpha-N-acetylglucosaminidase (EC 3. 2.1.50), one of the lysosomal enzymes required for the degradation of heparan sulfate. The disease is characterized by profound neurodegeneration but relatively mild somatic manifestations, and is usually fatal in the second decade. A mouse model had been generated by disruption of the Naglu gene in order to facilitate the study of pathogenesis and the development of therapy for this currently untreatable disease. Recombinant human alpha-N-acetylglucosaminidase (rhNAGLU) was prepared from secretions of Lec1 mutant Chinese hamster ovary cells. The enzyme, which has only unphosphorylated high-mannose carbohydrate chains, was endocytosed by mouse peritoneal macrophages via mannose receptors, with half-maximal uptake at ca. 10(-7) M. When administered intravenously to 3 month-old mice, rhNAGLU was taken up avidly by liver and spleen but marginally if at all by thymus, lung, kidney, heart, and brain (in order of diminishing uptake). The half-life of the enzyme was 2.5 days in liver and spleen. Immunohistochemistry and electron microscopy showed that only macrophages were involved in enzyme uptake and correction in these two organs, yet the storage of glycosaminoglycan was reduced to almost normal levels. The results show that the macrophage-targeted rhNAGLU can substantially reduce the body burden of glycosaminoglycan storage in the mouse model of Sanfilippo syndrome III B.     

Deletion of 20p 11.23→pter with normal growth hormone-releasing hormone genes

Using a molecular analysis of the DNA from a patient with a deletion of chromosome 20 [46,XX,del(20)(p11.23)], we have excluded the growth hormone-releasing hormone (GHRH) gene from the region 20p11.23→pter. The patient had minor facial anomalies, Rieger eye anomaly, a congenital heart defect, severe failure to thrive, and a neurosecretory problem in growth hormone (GH) secretion. Since the GHRH gene was previously mapped to chromosome 20, we used molecular genetic methods to determine whether the growth abnormalities were due to the deletion of this gene. DNAs of the patient and 2 normal control subjects were analyzed by quantitative Southern blotting using a DNA probe for the GHRH gene and 2 reference DNA probes mapping to chromosome 21. The GHRH gene was found to be present in 2 copies in the patient. This indicates that the gene for GHRH maps to the region outside the patient's deletion, in 20p11.23→qter. Furthermore, our results suggest that genes other than GHRH on 20p are important for developmental steps leading to normal neurosecretory function of GH and may also be involved in generating Rieger eye anomaly. Finally, GH deficiency and Rieger eye anomaly should be sought in other patients with deletions of 20p.     

Births of normal daughters after MicroSort sperm separation and intrauterine insemination, in-vitro fertilization, or intracytoplasmic sperm injection

The world's first deliveries of normal babies after use of flow cytometric separated human sperm cells (MicroSort) for preconception gender selection are reported. Offspring were of the desired female gender in 92.9% of the pregnancies. Most of these pregnancies and births were achieved after simple intrauterine insemination.      

Detecting pre-ovulatory luteinizing hormone surges in urine

The study objectives were to determine (i) if pre-ovulatory luteinizing hormone (LH) surges, undetected in urine by two immunoradiometric assays (IRMA), were detectable by an ultrasensitive immunofluorometric assay (IFMA) and (ii) the influence of creatinine adjustment on the detection and timing of the urinary LH surges. Daily urine specimens were contributed by healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for an epidemiological study conducted in 1983-1985. Specimens were selected as having been previously assayed by two IRMA without consistently detecting LH surges. These urine specimens were remeasured using an IFMA and adjusted for creatinine concentration. IFMA measurements revealed unambiguous LH surges in all cycles. Adjusting IRMA urinary LH values for creatinine concentrations revealed previously undetected LH surges in four of eight cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH surges by 1-5 days. These results demonstrate an IFMA that detects pre- ovulatory LH surges in unpreserved, frozen urine from cycles where such surges were previously undetectable. Further, creatinine adjustment can markedly affect detection and timing of the onset and peak of the urinary LH surge. While our analysis suggests that this adjustment improves the validity of the LH measure, this requires further investigation.      

Stereotypic responses to infection and inflammation

There is a sequence of Stereotypie metabolic changes in rats subjected to inflammation or infection. In each stress, rats respond with increases in body temperature and plasma insulin and with decreases in plasma zinc, ketone bodies, and free fatty acids. The data suggest that infection or inflammation causes an activation of phagocytic cells and also that leukocytic endogenous mediator, when injected into rats, causes some of the same alterations. Rats doubly vagotomized respond to infection in the same fashion as intact rats.In conducting the research described in this report, the investigators adhered to the Guide for the Care and Use of Laboratory Animals, as promulgated by the Committee on Care and Use of Laboratory Animals of the Institute of Laboratory Animal Resources, National Research Council. The facilities are fully accredited by the American Association for Accreditation of Laboratory Animal Care.The views of the authors do not purport to reflect the positions of the Department of the Army or the Department of Defense.     

Versuche einer passiven Übertragung der Tuberkuloseimmunität an Schafen

Ohne Zusammenfassung     

Deletion of 20p 11.23----pter with normal growth hormone-releasing hormone genes

Using a molecular analysis of the DNA from a patient with a deletion of chromosome 20 [46,XX,del(20)(p 11.23)], we have excluded the growth hormone-releasing hormone (GHRH) gene from the region 20p11.23----pter. The patient had minor facial anomalies. Rieger eye anomaly, a congenital heart defect, severe failure to thrive, and a neurosecretory problem in growth hormone (GH) secretion. Since the GHRH gene was previously mapped to chromosome 20, we used molecular genetic methods to determine whether the growth abnormalities were due to the deletion of this gene. DNAs of the patient and 2 normal control subjects were analyzed by quantitative Southern blotting using a DNA probe for the GHRH gene and 2 reference DNA probes mapping to chromosome 21. The GHRH gene was found to be present in 2 copies in the patient. This indicates that the gene for GHRH maps to the region outside the patient's deletion, in 20p11.23----qter. Furthermore, our results suggest that genes other than GHRH on 20p are important for developmental steps leading to normal neurosecretory function of GH and may also be involved in generating Rieger eye anomaly. Finally, GH deficiency and Rieger eye anomaly should be sought in other patients with deletions of 20p.