Enhanced activity of demineralised bone matrix augmented with xenogeneic bone morphogenetic protein complex in rats.

INTRODUCTION: Demineralised bone matrix (DBM) is an allograft material widely used as a bone filler and bone graft substitute. DBM contains bone morphogenetic proteins (BMPs), which induce and regulate bone formation during embryogenesis and in postnatal life. AIMS AND OBJECTIVES: To investigate the osteoinductivity of DBM augmented with xenogeneic BMP-complex at different doses. MATERIALS AND METHODS: Rat DBM was augmented with BMP-complex purified from porcine diaphyseal bone. RESULTS: Dorsal subcutaneous implantation of 25 mg rat allogeneic DBM augmented with 0, 3, 6 and 12 mg BMP-complex per gram of DBM resulted in dose dependant up-regulation of bone formation on day 21, as scored histologically and biochemically. CONCLUSIONS: Allogeneic DBM can be augmented with xenogeneically sourced BMP-complex to improve DBM performance in vivo. This work demonstrates the potential of BMP-complex augmented DBM to induce new bone formation with improved parameters of bone formation.

Lymphocyte adherence to myelinated tissue in multiple sclerosis.

A small subpopulation of human peripheral blood T lymphocytes has the capacity to adhere selectively to myelinated sections of human and nonhuman brain tissue. Adherence of lymphocytes from patients with multiple sclerosis is significantly greater than adherence of control lymphocytes. Monocytes inhibit binding in controls. This function appears to be lost by multiple sclerosis monocytes.

Phase shifting the circadian rhythm of neuronal activity in the isolated Aplysia eye with puromycin and cycloheximide. Electrophysiological and biochemical studies.

The effects of pulse application of puromycin (PURO) or cycloheximide (CHX) were tested on the circadian rhythm (CR) of spontaneous compound action potential (CAP) activity in the isolated Aplysia eye. CAP activity was recorded from the optic nerve in constant darkness at 15degreesC. PURO pulses (6, 12 h; 12--134 mug/ml) and CHX pulses (12 h, 500--2,000 mug/ml) caused dose-dependent phase delays in the CR when administered during projected night. PURO pulses (6 h, 125 mug/ml) caused phase advances when given during projected day and caused phase delays when given during projected night. In biochemical experiments PURO (12 h, 20 mug/ml) and CHX (12 h, 500 mug/ml) inhibited leucine incorporation into the eye by about 50%. PURO (12 h; 50, 125 mug/ml) also changed the molecular weight distribution of proteins synthesized by the eye during the pulse. The effect of PURO (12 h, 125 mug/ml) on the level of incorporation was almost completely reversible within the next 12 h but the phase-shifted eye showed an latered spectrum of proteins for up to 28 h after the pulse. In electrophysiological experiments spontaneous CAP activity and responses to light were measured before, during, and after drug treatments. In all, eight parameters in three periods were analyzed quantitatively. Of these 24 indices, only 3 showed significant changes. PURO increased spontaneous CAP frequency by 67% 0-7 h after the drug pulse and increased the CAP amplitude of the tonic light response by 23% greater than 7 h after the pulse. CHX increased the intraburst spontaneous CAP frequency by 33% during the pulse and CAP frequency of the tonic light response by 32% 0-7 h after the pulse. The above data indicate that phase-shifting doses of PURO and CHX inhibit protein synthesis in the eye without causing adverse electrophysiological effects, and suggest that protein synthesis is involved in the production of the CR of the isolated Aplysia eye.

Antinuclear antibodies in multiple sclerosis.

Low levels of antinuclear antibodies (ANAs) were found by indirect immunofluorescence in the serum of patients with multiple sclerosis (MS). Antibodies were found in 22 (81%) of 27 patients with MS and four (20%) of 20 healthy control subjects, with human epithelial (HEp-2) cells as substrate. Antinuclear antibody titers ranged from 8 to 32 in patients with MS and rarely reached above 8 in control subjects. The most common fluorescence patterns produced by MS serums were diffuse, fine speckled, and diffuse with fine-speckled nuclear fluorescence. Large nucleolar speckles and cytoplasmic fine speckles were also seen. Similar, although stronger patterns were seen in control subjects with positive tests for systemic lupus erythematosus. No correlation was found between ANA and antimeasles antibody titers. The presence of a heterogeneous population of circulating antibodies to a variety of nuclear and cytoplasmic antigens lends further support to the concept that altered immune reactivity exists in MS.

Lymphocyte adherence in multiple sclerosis.

It has been reported that peripheral blood lymphocytes from patients with multiple sclerosis (MS) adhere to measles-infected human epithelial cells in significantly greater numbers than do lymphocytes from healthy volunteers or patients with other neurologic diseases. We have confirmed this observation in three separate studies, and have investigated the relationship of lymphocyte adherence to the clinical state. Lymphocyte adherence determination values correlated with the degree of certainty of the clinical diagnosis of MS, and lymphocyte adherence values in individual patients increased during clinical exacerbations. Judicious use of this test may facilitate the diagnosis of MS.

Identification and primary structural analysis of peptide II, an end-product of precursor processing in cells R3-R14 of Aplysia.

Peptide II, which is encoded on a gene for a precursor protein in abdominal ganglion neurons R3-R14, was purified from extracts of abdominal ganglia of Aplysia californica. Native peptide II comigrates with synthetic standards on HPLC under isocratic conditions. Amino acid sequence and composition analyses indicate that the sequence of peptide II is Glu-Ala-Glu-Glu-Pro-Ser-Phe-Met-Thr-Arg-Leu, as predicted from the precursor. The molluscan cardioexcitatory peptide Phe-Met-Arg-Phe-amide was also identified in abdominal ganglion extracts by similar means. The large amount of peptide II recovered (100 ng/ganglion), and its location on the precursor between two pairs of basic residues, strongly suggest that the precursor is processed into peptide II and at least two other peptides. Although cells R3-R11 have been postulated to play a role in cardiovascular control, peptide II was without effect at less than or equal to 10(-4) M concentrations on identified abdominal ganglion neurons, the gastroesophageal artery or the heart. The physiological role of peptide II therefore remains to be elucidated.

Presence of immunoreactive alpha-bag cell peptide[1-8] in bag cell neurons of Aplysia suggests novel carboxypeptidase processing of neuropeptides.

alpha-bag cell peptide (alpha BCP) is a putative neurotransmitter released from bag cell neurons of the marine mollusc Aplysia. alpha BCP is present in bag cell extracts and releasate from bag cells in two neuroactive forms: alpha BCP[1-9] and alpha BCP[1-8]. alpha BCP[1-8] is 30 times as potent as [1-9] in inhibiting target neurons, suggesting that both forms of the peptide serve as neurotransmitters. However, biochemical and molecular genetic data suggest that only alpha BCP[1-9] is originally cleaved directly from a larger precursor protein and that generation of alpha BCP[1-8] would require an unusual C-terminal leucine cleavage of alpha BCP[1-9]. To further ascertain which forms of alpha BCP are normally present in bag cells, we generated highly specific antisera to each peptide. We found intense immunostaining for both peptides in bag cell somata and nerve terminals. Moreover, both forms were stable in bag cell extract for at least 1 hr, which suggests that proteolysis in the extracts had been effectively inhibited. These results suggest that both alpha BCP[1-8] and [1-9] are normally present in bag cell somata and terminals and that a small amount of alpha BCP[1-9] is processed to alpha BCP[1-8] in vesicles before release. The results support the interpretation that the activity of an intravesicular carboxypeptidase generates alpha BCP[1-8] and thereby regulates the amount of inhibitory activity released during a bag cell discharge.

Coexistence of egg-laying hormone and alpha-bag cell peptide in bag cell neurons of Aplysia indicates that they are a peptidergic multitransmitter system.

Double-label immunocytochemistry reveals that immunoreactivity for two putative peptide transmitters, egg-laying hormone and alpha-bag cell peptide, co-exist in most bag cell somata and processes in the abdominal ganglion of the marine mollusc Aplysia. Together with previous physiological and biochemical data these findings indicate that the neuroendocrine bag cells are a multitransmitter system which utilizes two or more peptides derived from a common precursor.

Synthesis of prostaglandin E by peritoneal macrophages from NZB/W mice.

Peritoneal macrophages from NZB/W (murine lupus) mice spontaneously produce less prostaglandin E (PGE) than peritoneal macrophages from immunologically normal mice. Reduced PGE synthesis is seen as early as 2 months of age and becomes more profound as disease progresses. It is suggested that impaired production of PGE by peritoneal macrophages from NZB/W mice may account in part for abnormal macrophage function observed in these animals.

Ideology and technology: the social context of procreative technology.

Biomedical practices and research in procreation are shaped by three ideologies deeply rooted in American society: patriarchy with its control of women's bodies in the interest of men's procreative concerns and with its focus on 'seeds' and therefore genetics; technology as an ideology of efficiency, productivity, rationality, and control; and capitalism both as an ideology and as a practice, a mechanism that markets technologies of procreation.

Technical note: magnetic resonance imaging-guided pre-operative breast localization using "freehand technique".

A 1.5 cm focus in the breast with intense gadolinium uptake was incidentally detected during magnetic resonance (MR) imaging evaluation of a cluster of microcalcifications. Because the apparent mass was both mammographically and sonographically occult, MR imaging was used to guide a needle by "freehand technique" to the lesion, permitting successful pre-operative localization and subsequent surgical excision of the area.

Women, providers, and control.

Childbirth in America is dominated by a management perspective that emphasizes the efficient removal of a fetus from a woman's body. This article discusses the obvious and not so obvious ways that routine American management of childbirth systematically strips women of power and control. It is argued that, although providers may be well-meaning and nurturing in their care of childbearing women, their approach is most often nurturing to weakness, rather than strength.

False-positive iodine-131 body scan caused by a large renal cyst.

Focal I-131 accumulation is generally a reliable indicator of functioning thyroid tissue or a differentiated thyroid cancer metastasis. Normal accumulation of activity may be seen in areas such as the intestinal tract, liver, and salivary glands. This report describes a patient with significant accumulation of I-131 in the right upper quadrant of the abdomen. The abnormality, first thought to represent metastatic thyroid carcinoma, was subsequently proven to be accumulation within a large renal cyst.

The products of conception: the social context of reproductive choices.

This paper addresses the changing ideology regarding reproduction, an evolving American, and potentially worldwide, value system regarding children and parenthood. Children are increasingly being seen as products, and the new technology of reproduction, including the sale of reproductive material and services and especially prenatal diagnosis and selective abortion, encourage this commodification of the fetus. While the new technology does indeed offer new choices, it also creates new structures and new limitations on choice. In the contemporary American social structure, these choices are inevitably couched in terms of production and commodification, and thus do not offer individuals genuine choice or control.

KIE: The potential impact of reproductive technologies on attitudes toward children and parenthood is explored by Rothman, an American sociologist. She discerns an emerging American value system that is beginning to view children as commodities. A growing emphasis on "perfect" babies and on "quality control" mechanisms such as amniocentesis and selective abortion has negative implications for the willingness of individuals and society to accept the disabled. Rothman concludes that, while the new technologies appear to expand the number of reproductive choices, these choices in reality are limited by social and economic constraints. In her commentary on Rothman's essay, British sociologist Margaret Stacey contrasts her country's collectivist approach to health needs with the American capitalist approach, and warns that the new reproductive options must be evaluated in terms of their impact on women and children.