Interferometric coupling of the Keck telescopes with single-mode fibers.

Here we report successful interferometric coupling of two large telescopes with single-mode fibers. Interference fringes were obtained in the 2- to 2.3-micrometer wavelength range on the star 107 Herculis by using the two Keck 10-meter telescopes, each feeding their common interferometric focus with 300 meters of single-mode fibers. This experiment demonstrates the potential of fibers for future kilometric arrays of telescopes and is the first step toward the 'OHANA (Optical Hawaiian Array for Nanoradian Astronomy) interferometer at the Mauna Kea observatory in Hawaii. It opens the way to sensitive optical imagers with resolutions below 1 milli-arc second. Our experimental setup can be directly extended to large telescopes separated by many hundreds of meters.

Revascularization of kidneys with totally occluded renal arteries.

Nephrectomy has been the accepted treatment for renovascular hypertension due to an occluded renal artery but successful revascularization of occluded renal arteries has resulted in partial return of function and relief of hypertension. We performed aorticorenal bypass operations on four patients whose renal arteries were not patent. One graft failed immediately, two remained open for four to six months, and one is functioning at two years. In 70 other cases in which totally occluded arteries were revascularized, the overall patency rate was 96%. Hypertension was relieved for controlled in 77%.

Hypertension in a pediatric and adolescent population following kidney transplantation.

The post-renal transplant courses of 53 children and adolescents were evaluated for the prevalence and the etiology of hypertension. The blood pressures were averaged over specific time periods following transplantation and converted to percentile ranks according to standards for age. The number of antihypertensives employed to control blood pressure was assessed. Factors such as sex, obesity, race, donor source, antigen match, steroid administration, rejection, recurrent glomerulonephritis, pre-transplant nephrectomy, renal function and proteinuria were assessed as to their importance in producing hypertension or normotension in the post-transplant period. The average blood pressure was well within acceptable range shortly after transplantation. The patients requiring antihypertensives to control blood pressure dropped by two years post transplant. Chronic rejection was by far the most important factor influencing average blood pressure and the need to employ antihypertensives. Alternate-day prednisone and good graft function were important in establishing the normotensive state.

The role of various risk factors in living related donor renal transplant success.

Assessment of living related donor (LRD) survival statistics offers the opportunity to gauge the effects of recipient characteristics without the perturbations of viability, function, and antigen sharing that are inherent in cadaveric organ grafting. From January 1, 1969 to January 1, 1979, 167 LRD grafts were performed. Crude patient survival at one year is 92% and 84% at five years. Graft function at one year is 79%, and at five years it is 64%. One year patient survival has steadily improved: 1969-73: 83%, 1973-75: 91%, 1975-79: 98%. Graft survival improved during the first two periods and has since remained unchanged. HLA identical grafts showed the expected advantage compared with single haplotype grafts (93 vs 74%). Recipient age was without effect until 50 years, all younger subgroups having one-year patient survival of 92-95%, while those older than 50 had a one-year survival of 60%. Juvenile diabetes was associated with a one-year patient survival of 85% and graft survival of 74%. Glomerulonephritis did not affect early graft survival statistics, but there was a greater frequency of graft loss after 2.5 years, with function at five years of 51 versus 68% for recipients with all other diagnoses. Cadaveric graft statistics vary with recipient race when adjusted to exclude older patients and diabetics, white recipient one-year graft survival 74%, black 38%. No meaningful difference exists among LRD recipients as to graft function, but there is a trend toward improved black patient survival. This suggests that there is not an inherent difference in immune response to genetically similar grafts, but that the disparate results with racially mixed donor-recipient combinations rests with other factors.

Reaction of anti-idiotypic antibody with the hapten-binding site of a myeloma protein.

Rabbit antiserum was prepared against mouse myeloma Protein-315, an IgA protein with specificiy toward the 2,4-dinitrophenyl group. After absorption of the antiserum with another IgA myeloma protein and with affinity-labeled Protein-315, the antiserum was specific for idiotypic determinants on Protein-315. Monovalent ligands that bind to Protein-315 with high affinity strongly inhibited the reaction of the protein with its anti-idiotypic antiserum. This indicated that the region of the hapten-binding site is a major idiotypic determinant. The myeloma protein is thus similar to rabbit antibenzoate antibody in this respect. These results, considered in conjunction with other data in the literature, indicate that an anti-idiotypic antiserum prepared in an isologous or heterologous species can recognize the same determinant, in this case the region comprising the ligand-binding site. Quantitative aspects of the data indicate that there is competition between the hapten and antiidiotypic antibodies for the site.

Quantitative investigations of idiotypic antibodies. IV. Inhibition by specific haptens of the reaction of anti-hapten antibody with its anti-idiotypic antibody.

Rabbit anti-idiotypic antibodies were prepared by injection of specifically purified anti-p-azobenzoate antibodies (D) from individual donor rabbits. Benzoate derivatives were found to be strong inhibitors of the reactions of D with anti-D antisera. There was a close correlation between the combining affinities of the benzoate derivatives used and their effectiveness as inhibitors. Compounds tested that are chemically unrelated to benzoate were ineffective. The results indicate either that the combining site of anti-benzoate antibody is part of an important idiotypic determinant, which is sterically blocked by hapten, or that the hapten induces a conformational change which alters idiotypic determinants not involving the active site. Such conformational changes, if they occur, must be restricted since hapten has little effect on the reactions of F(ab')(2) fragments of anti-benzoate antibodies with antisera directed to rabbit fragment Fab and no detectable effect on reactions with antibodies directed to allotypic determinants.