A conservative, low-cost superovulation regimen.

The protocol reported decreases the cost and inconvenience of inducing the growth of multiple ovulatory follicles in selected infertility patients. Safety was maintained by treating patients with relatively small amounts of exogenous gonadotropins and using patient response to slowly increase gonadotropin stimulation in subsequent cycles. The pregnancy rate was 26% per cycle. For couples with male factor infertility, it was 20% per cycle. This regimen may be especially suitable for the practitioner with only a few patients requiring this therapy who may not have the capacity to obtain daily estradiol levels.     

Adhesiveness of human ligament fibroblasts to laminin

The adhesiveness of fibroblasts from the human anterior cruciate and medial collateral ligaments to the laminin molecule was studied, with particular emphasis on the intrinsic differences between fibroblasts from the two ligaments. Cellular adhesion strength, adhesion area, laminin concentration, and seeding time were examined. Cell adhesion to laminin anchored with poly-D-lysine to a cleaned cover glass was measured with a micropipette micromanipulation system after seeding. The adhesion strength of fibroblasts from the anterior cruciate ligament to laminin was greater than and significantly different from that of fibroblasts from the medial collateral ligament, depending on the laminin concentration. Fibroblasts from the anterior cruciate ligament also exhibited an increase in adhesion strength, dependent on laminin concentration of as much as 30 μg/ml, at which the laminin receptors were thought to be saturated. Fibroblasts from the medial collateral ligament did not show such an increase except at laminin concentrations of 5–10 μg/ml. There was no significant difference in adhesion area between fibroblasts from the two ligaments except after 45 minutes at a laminin concentration of 40 μg/ml. For both, the adhesion to laminin showed little correlation to seeding time during periods of as long as 60 minutes. Measurements of adhesion area also failed to show a significant correlation to seeding time for fibroblasts from either ligament at laminin concentrations of 20 and 40 μg/ml. Adhesion strength normalized by adhesion area had no correlation to seeding time. With all times taken into account, however, normalized adhesion strength for fibroblasts from the anterior cruciate ligament was approximately two times greater than and significantly different from that for fibroblasts from the medial collateral ligament at laminin concentrations of 20 and 40 μg/ml. Fibroblasts from the anterior cruciate ligament adhere more strongly to laminin than do those from the medial collateral ligament. This study may prove useful in the understanding of fibroblast adhesion to the basal lamina within the extracellular matrix and may provide insight into the natural healing processes of the anterior cruciate and medial collateral ligaments.     

Monoamine release from dopamine-depleted rat caudate nucleus reinnervated by substantia nigra transplants: An in vivo electrochemical study

Previous studies have shown that fetal substantia nigra (SN) transplanted into a cavity overlying a dopamine (DA)-denervated caudate nucleus can reverse a number of the behavioral abnormalities induced by the denervation. While some histochemical and physiological evidence suggests that this reversal is the result of a functional DA input from the transplant to the host brain, there is little direct evidence for transmitter release from ingrowing graft-derived nerve fibers. In the present work in vivo electrochemistry was used to analyse the magnitude, time course and spatial distribution of neurotransmitter releases evoked by local application of potassium (K+) from DA-depleted, SN transplant-reinnervated striatum. Animals were injected unilaterally with 6-hydroxydopamine (6-OHDA) into the SN and screened by measuring apomorphine-induced rotation. Some were then given SN grafts, which were placed in a 'delayed cavity' just dorsal to the lesioned striatum. Nafion-coated graphite epoxy capillary (GEC) electrodes were employed for the electrochemistry to minimize signals derived from ascorbate or acidic DA metabolites. The GEC electrode was fixed to a K+-filled micropipette and this assembly was used to map the caudate nucleus of control, 6-OHDA-treated, and 6-OHDA-treated, grafted animals. The morphometric relationships between striatal recording sites and transplant location were subsequently verified histologically. Releases from striatal sites within 1.0 mm of the SN grafts were slightly, but not significantly, less than those obtained from control caudate.(ABSTRACT TRUNCATED AT 250 WORDS)     

Extended Indications for Lung Volume Reduction Surgery in Advanced Emphysema

Background. Lung volume reduction surgery has shown early promise as a palliative therapy in severe emphysema. Selection of potential candidates has been based on certain functional and anatomic criteria, and a variety of operative contraindications have been proposed.

Methods. Over 15 months, we performed lung volume reduction surgery in 85 patients selected on the basis of severe hyperinflation with air trapping, diaphragmatic dysfunction, and disease heterogeneity. Patients were not excluded on the basis of severe hypercapnia, steroid dependence, profound pulmonary dysfunction, or inability to complete preoperative rehabilitation.

Results. We observed significant improvements in pulmonary function, exercise capacity, and dyspnea, with an acceptable 30-day perioperative mortality of 7% and actuarial survival of 90% and 83% at 6 and 12 months, respectively. In each “high-risk” group, perioperative mortality, actuarial survival to 1 year, and functional results were equivalent, and in some cases superior, to those in the corresponding “low-risk” patients.

Conclusions. Severe hypercapnia, steroid dependence, profound pulmonary dysfunction, and inability to complete preoperative rehabilitation do not preclude successful lung volume reduction surgery and should not be regarded as absolute exclusionary criteria.     

Nursing Diagnosis by Computers: An Application of Neural Networks

In a pilot-test application of the neural network, test case diagnoses made by the ART-2 neural network agreed with those made independently by nurses. The main conclusion is that the ART-2 neural network is promising as a decision-making aid. It can handle probabilistic and ill-defined data through a process of pattern recognition without programming rules. A disadvantage is that the ART-2 neural network requires "training" by the nurse using at least one example to define a diagnosis. In practice, however, this requirement does not affect its usefulness. Moreover, providing the ART-2 neural network with several training examples enables it to identify new patterns that are "close" to the textbook case but vary in one or more characteristics.     

Agonistic and antagonistic activities of bacterially derived Rhodobacter sphaeroides lipid A: comparison with activities of synthetic material of the proposed structure and analogs.

Lipid A from the photosynthetic bacterium Rhodobacter sphaeroides (RSLA) has been previously shown to antagonize many of the effects of endotoxins from more pathogenic gram-negative bacteria. We have reported on the synthesis of the proposed structure of RSLA and determined that bacterially derived RSLA is not identical to its proposed structure (W.J. Christ, P. D. McGuinness, O. Asano, Y. Wang, M. A. Mullarkey, M. Perez, L. D. Hawkins, T. A. Blythe, G. R. Dubuc, and A. L. Robidoux, J. Am. Chem. Soc. 116:3637-3638, 1994). Here we report results of analyzing the antagonistic and agonistic activities of bacterially derived RSLA in comparison with the activities of chemically synthesized material of the proposed structure of RSLA and analogs. Results indicated that all compounds were approximately equally potent at inhibiting endotoxin-induced release of tumor necrosis factor alpha from human monocytes and human whole blood as well as endotoxin-induced generation of nitric oxide in murine macrophages. In addition, all compounds were of equivalent potencies at inhibiting the binding of 125I-labelled lipopolysaccharide derivatized with 2-(p-azido-salicylamido) ethyl-1-3'-dithiopropionate to murine macrophages. Higher concentrations of bacterially derived RSLA (10 to 100 microM) were agonistic in human and murine assays. In gamma interferon-treated murine macrophages, agonism was exhibited at concentrations as low as 100 nM. In contrast, all synthetic materials were either dramatically less agonistic or devoid of agonistic activity when tested at concentrations as high as 100 microM. It is possible either that bacterially derived RSLA contains a small amount of a highly agonistic impurity or that the agonistic activity of RSLA is intrinsic to its molecular structure. In either case, these biological results support our previous report concluding that biologically derived RSLA is not identical to synthetic material of its proposed structure.     

Progress in 3-D treatment planning for photon beam therapy

The purpose of this report is to study the feasibility of improving dose distributions using non-coplanar photon beams from a linear accelerator. Non-coplanar beams may enter the patient in any arbitrary configuration. This type of treatment technique requires a three-dimensional (3-D) planning system. Clinical examples are used to illustrate the general problems in 3-D treatment planning, and the potential improvement over coplanar beam treatments. Features of a treatment planning system for 3-D planning are discussed.