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J R Lieberman

Publications and source records attributed to J R Lieberman.

60 records · Page 4Linked to original sources
PubMed1988

Repair of Achilles tendon ruptures with Dacron vascular graft.

A technique has been developed for the repair of Achilles tendon ruptures that allows for early mobilization of the patient. A Dacron vascular graft is woven from distal to proximal and across the site of the rupture in a Bunnell-type fashion. The patients are immobilized in a short-leg cast for two weeks and are then fitted for a posterior fiberglass splint. Seven patients with acute ruptures who were treated with repair with the Dacron graft were followed for a period ranging from ten to 38 months. They were allowed to return to their normal level of activity approximately five months after surgery. There have been no reruptures. This technique also holds particular promise for the late reconstruction of an Achilles tendon rupture as well as for the treatment of partial tears in the severely degenerated tendon.

Achilles Tendon↗
PubMed1978

Requirement of the light-harvesting pigment.protein complex for magnesium ion regulation of excitation energy distribution in chloroplasts.

Cation regulation of excitation energy distribution was examined in chloroplasts isolated from (a) pea seedlings, grown in intermittent illumination, which contain no light-harvesting complex, (b) a barley mutant which is deficient in the major polypeptide component of the light-harvesting complex, and (c) a soybean mutant which contains a reduced amount of light-harvesting complex. It was found that: (1) Mg2+-induced increase in Photosystem II fluorescence at room temperature is small in the chloroplasts of the soybean mutant, smaller in the barley mutant, and almost absent in the light-harvesting complex-less chloroplasts of pea as compared to their respective controls. (2) Mg2+-induced increase in the F685/F730 emission peak ratio at 77 K is not detected in the isolated chloroplasts of the intermittent light-grown pea and the barley mutant. (3) Pre-illumination induced State 1-State 2 and adaptation in vivo is absent in the barley mutant and is less pronounced in the soybean mutant as compared to their respective controls. (4) Increase of slow fluorescence decay upon addition of Mg2+ observed in control chloroplasts was not detected in chloroplasts of intermittent-light grown peas. These results confirm earlier conclusions (Armond, P.A., Arntzen, C.J., Briantais, J.M. and Vernotte, C. (1976) Arch. Biochem. Biophys. 175, 54--63; Davis, D.J., Armond, P.A., Gross, E.L. and Arntzen, C.J. (1976) Arch. Biochem. Biophys. 175, 64--70) that light-harvesting complex is required for the Mg2+-induced regulation of the excitation energy distribution between Photosystems I and II. The characteristic P-S decay and I-D dip of the in vivo fluorescence inductions (Kautsky effect) were not significantly altered in the light-harvesting complex-less and the light-harvesting complex-deficient chloroplasts as compared to their respective controls. These results indicate that light-harvesting complex is not obligatorily required to observe the P-S decay or the I-D dip.

Cell-Free System↗
PubMedDate not supplied

Development of an animal model for prostate cancer cell metastasis to adult human bone.

BACKGROUND: Prostate cancer metastases to bone are associated with significant morbidity and mortality. Presently, there is little known about the biological interaction between prostate cancer cells and bone. Development of an animal model using adult human bone will enhance our ability to study the biology of prostate cancer metastasis to bone. METHODS: Bone was harvested from patients undergoing total joint arthroplasty and implanted in the hindlimbs of pre-treated SCID mice. Two months after bone implantation 4 x 104 prostate cancer cells (PC-3 or LAPC-4) were injected near the bone implantation site. The animals were sacrificed approximately 8 to 12 weeks after the injections of the cells. Complete histological analysis including immunostaining was performed. RESULTS: Both the PC-3 and LAPC-4 prostate cancer cells homed to the human bone implant, specifically the reconstituted bone marrow cavity. Analysis of the bone-tumor interaction after injection of PC-3 cells revealed strong labeling for PTHrP, TNF alpha and IL-6, consistent with osteoclast recruitment and osteoclast activity. These cells also were positively stained for CK18. After cellular injection of LAPC-4 cells, there was strong labeling for TNF alpha, IL-6, and IL-1 (osteoclast recruitment and osteolytic activity). PTHrP staining was also noted. The bone cells were strongly stained for osteocalcin, and the tumor cells for PSA. CONCLUSIONS: These data suggest that the tumor cells may induce an osteolytic response to enhance their ability to metastasize to bone. This animal model allows us to study the biologic interaction between prostate cancer cells and human bone and may enhance our understanding of the events associated with prostate cancer metastasis to bone.

Adenocarcinoma↗