Biomedical subjects

J M Greco

Publications and source records attributed to J M Greco.

At least 19 recordsLinked to original sources

PubMed1992

Surgically assisted rapid palatal expansion: an outpatient technique with long-term stability.

This study presents the results of surgically assisted rapid palatal expansion done on an outpatient basis in 19 patients with a mean age of 30 years. Postsurgical and postorthodontic evaluation (mean, 2.4 years) showed a mean relapse rate of 8.8% in the canine region, 1% in the premolar region, and 7.7% in the molar region. These results show that the surgical procedure is feasible on an outpatient basis and the technique, as outlined, yields a stable long-term result.

Adolescent↗

PubMed1991

Anatomic basis for use of a distal pedicle leg flap.

The cutaneous blood-supply of the limbs is ensured by three types of arteries: the large septo-cutaneous arteries, the slender musculocutaneous arteries, and the rare satellites of the cutaneous nerves. The skin cover of the outer aspect of the leg is particularly well vascularized thanks to its special situation, centered on the intermuscular septa bounding the outer compartment of the leg. Neuromuscular arteries are rare at this site, but there are numerous septo-cutaneous arteries at intervals along the septa. This anatomic study is based on 20 dissections and a radiologic survey and provides findings confirming the reliability of a distally based lateral leg flap. This pedicle arises from the fibular artery behind and the anterior tibial artery in front. It is situated, on average, 10.8 cm from the lateral malleolus, thus allowing coverage of peripheral losses of substances at the malleoli and heel.

Blood Vessels↗

PubMed1990

Cephalometric analysis of long-term airway space changes with maxillary osteotomies.

The cephalometric radiographs of 13 patients without sleep apnea who had undergone isolated maxillary surgery were studied. The authors found increases in both the nasopharyngeal and hypopharyngeal airway spaces 3 to 5 years after surgery. The results suggest that adaptive processes occur in both the upper and lower jaw, which contribute to an enlarged airway after surgery.

Adaptation, Physiological↗

PubMed1990

Long-term airway space changes after mandibular setback using bilateral sagittal split osteotomy.

Eleven patients were evaluated retrospectively for their long-term changes in hypopharyngeal airway space after surgical correction of mandibular hyperplasia. All patients had undergone mandibular setbacks by way of bilateral sagittal split osteotomies using rigid fixation. The cephalometric evaluation of hypopharyngeal airway space was based on stable craniofacial landmarks. The results of this study indicate that mandibular setback procedures create relative narrowing of the hypopharyngeal airway space, as seen on lateral cephalometric radiographs, which in isolated cases might contribute to the development of an obstructive sleep apnea syndrome. The 2-dimensional evaluation of hypopharyngeal airway space and the clinical implications of the results are discussed.

Adolescent↗

PubMed1990

[Technical analysis of reduction mammaplasty. A personal method].

The authors describe the evolution of their ideas concerning the principles of reduction mammaplasty. The elements for their analysis are based on a study of 1,287 cases of breast reduction following a pre-established technique. Basic concepts in preoperative markings and surgical techniques are discussed. Their conclusions lead to a surgical method, both simple and secure, avoiding unfavourable results, which may be a helpful guide for residents and young plastic surgeons.

Breast↗

PubMed1990

[Inner canthus--anatomical junction. A surgical entity].

The medial canthus is a surgical entity. The anatomical features are defined from a dissection of eight orbital regions. The pathways of carcinological invasion and the anatomical barriers are considered. The conclusions are discussed in the light of the data reported in the literature.

Dissection↗

PubMed1989

Health physics measurement of Princeton Tokamaks, 1977-1987.

The Princeton Plasma Physics Laboratory (PPPL) began fusion experiments in 1951. In the early years, the major health physics concerns were associated with x radiation produced by energetic electrons in the plasma. Within the past year, neutron and 3H production from 2H-2H (represented hereafter as D-D) reactions has increased significantly on the larger fusion devices. Tritium retention noted in graphite tiles underscores the significance of material selection in present and future 3H-fueled fusion devices. This paper reports on operational health physics radiation measurements made on various PPPL machines over the past 10 y.

Health Physics↗

PubMed1988

[Maxillofacial injuries due to firearms. Retrospective study apropos of 60 cases].

Sixty cases have been treated between 1969 and 1986. The same primary treatment's principles have left for the last twenty years. Secondary treatment only, realized between the second and the third month has much benefited by plastic surgery's progress.

Adolescent↗

PubMed1987

Zoladex (ICI 118,630): clinical trial of new luteinizing hormone-releasing hormone analog in metastatic prostatic carcinoma.

Twenty-seven patients with metastatic adenocarcinoma of the prostate were treated with the new luteinizing hormone-releasing hormone analog, Zoladex (ICI 118,630) for up to ninety-eight weeks. Initially, treatment was randomized between Zoladex 250 micrograms and 500 micrograms self-injected subcutaneously every day for a minimum period of twelve weeks following which a sustained-release, once-monthly depot formulation of Zoladex 3.6 mg s.c. was used. Acute rises in serum gonadotropins and testosterone during the first two days were followed by declines in hormone levels over the following three weeks. Median time to castration with 500 micrograms/day was twenty-two days compared with forty-three days with 250 micrograms/day (p = 0.06). No significant endocrinologic changes occurred during the transfer to the depot, and serum testosterone remained 95 per cent suppressed throughout the duration of the study. After three months the median daily serum Zoladex concentrations ranged between 0.47 and 0.53 ng/ml and were not significantly different among the three dosage forms. No specific correlation among serum Zoladex concentrations, endocrinologic parameters, and tumor response rates were found. Hot flashes initially, and decreased libido were the only common complaints. Zoladex was well tolerated, and no side effects required dose-modification or removal from the study. Tumor response rates up to one year appeared to be comparable to the conventional endocrine therapies. This analog in monthly depot formulation is recommended for further clinical evaluation.

Adenocarcinoma↗

PubMed1985

Formation of lipid-linked oligosaccharides by MOPC 315 plasmacytoma cells. Decreased synthesis by a nonsecretory variant.

MOPC 315 is a BALB/c plasmacytoma which secretes a trinitrophenol-binding IgA lambda 2 paraprotein. We have investigated the incorporation of [3H]mannose into lipid-linked oligosaccharide precursors in wild-type MOPC 315/J and variant nonsecretory 315/P cells. In pulse labeling experiments, no differences could be detected in the ability of the two cell types to incorporate [3H]mannose into lipid-linked oligosaccharides containing 5 or less mannose residues. In contrast, quantitation of the incorporation of [3H]mannose into larger lipid-linked oligosaccharides and proteins revealed a 49 and 40% decrease, respectively, in the 315/P cells compared to wild-type cells. Further characterization of the lipid-linked structures documented a marked decrease in glucosylated oligosaccharides isolated from 315/P cells. When membranes from the two cell lines were analyzed for their ability to transfer [3H]glucose from UDP-[3H]glucose to [3H]glucosylphosphoryldolichol, an apparent deficiency was noted in the 315/P preparations. However, if assay conditions were adjusted to include AMP in the reaction mixtures, no differences in the in vitro synthesis of [3H]glucosylphosphoryldolichol or [3H]glucose-labeled oligosaccharide-lipid could be detected. In these reactions AMP was found to prevent hydrolysis of UDP-[3H]glucose by inhibiting nucleotide pyrophosphatase (EC 3.6.1.9), the specific activity of which was determined to be more than 100 times greater in variant 315/P compared to wild-type MOPC 315/J cells. This large difference in specific activity was not accompanied by similar differences in the activity of several other enzymes analyzed. A decrease in whole cell UDP-glucose pool size was not detected in 315/P cells. Therefore, if nucleotide pyrophosphatase is important for the control of substrates for glycosylation, it must regulate nucleotide sugar levels at a site other than the cytoplasm of cells, perhaps at the location of synthesis of the larger lipid-linked oligosaccharides.

Animals↗

PubMed1985