Showing papers by "University of Medicine and Dentistry of New Jersey published in 1983"

Evaluation of collagen crosslinking techniques

Abstract: The properties of collagen films crosslinked by physical and chemical techniques were compared to the properties of films crosslinked with glutaraldehyde (GTA). Physical techniques studied include exposure to short wave (254 nm) u.v. irradiation and severe dehydration. Chemical techniques studied include immersion of collagen films in aqueous solutions of cyanamide or GTA. Collagen films exposed to combinations of aqueous solutions of cyanamide and severe dehydration had moduli of elasticity, swelling ratios and resistance to bacterial collagenase similar to films crosslinked with GTA. Theoretical calculations based on amino acid composition indicate that approximately seven times as many amino acid residues are capable of forming crosslinks using cyanamide or severe dehydration procedures as compared to GTA crosslinking. In addition, using severe dehydration or cyanamide forms crosslinks involving both amino and carboxyl residues which may allow these procedures to act synergistically. Based on our studi...

Complications Occurring during Enteral Nutrition Support: A Prospective Study

Abstract: A review of 253 patients treated with enteral nutrition support via tube feedings is presented for the purpose of evaluating the incidence of complications. Thirty patients, (11.7%) experienced either gastrointestinal, (6.2%) mechanical (3.5%), or metabolic (2.0%) complications. The recognition and treatment of such complications are discussed and it is concluded that tube feedings are safely tolerated by most patients; however, constant attention must be exerted to either avoid or recognize such complications.

Organization of HRP‐labeled trigeminal mandibular, primary afferent neurons in the rat

Abstract: Horseradish peroxidase (HRP) applied to the transected mandibular division of the trigeminal (V) ganglion was transported anterogradely to pri-mary afferent terminal zones in the dorsal and dorsomedial trigeminal brain-stem nuclear complex (TBNC). Primary V afferents of ganglionic origin were also visible in the ipsilateral cerebellar cortex (crus I and II, paraflocculus) and the dentate, cuneate, solitary, supratrigeminal, and dorsal motor vagal nuclei, parvicellular reticular formation, area postrema and C1–C6 dorsal horn, laminae I–V. Contralateral subnucleus caudalis and C1–C2 dorsal horn were also innervated by primary afferents which crossed in the spinal gray to terminate medially, primarily in laminae I, II, and V. Almost all of these projections were also labeled in various combinations when HRP was applied to individual sensory branches of the mandibular nerve: lingual, infe-rior alveolar, mylohyoid, and auriculotemporal. Transganglionic transport of HRP in the latter four cases revealed strong evidence for mtradivisional somatotopy among the four branches in both the ganglion and TBNC. Cell bodies innervating posterior and/or lateral portions of the head and face (i.e., auriculotemporal and mylohyoid) were found with greater frequency in dor-sal mandibular ganglion regions, while somata supplying more rostral oral-perioral regions (i.e., lingual and inferior alveolar) were predominant ventrally. Components of the mandibular projection to the TBNC were organized topographically in at least some portion of all of its three dimen-sions. Subnuclear preferences were not clear-cut; all four nerves innervated at least some portion of principalis, oralis, interpolaris, and caudalis, save for mylohyoid, which did not project to caudalis. Lingual fibers were most prominent in principalis and oralis, occupied medial portions of the mandib-ular projection to the TBNC, and descended only to rostral caudalis, most notably laminae I-III. Inferior alveolar afferents were ubiquitous in the mandibular component of the TBNC and C1–C2, save for its far lateral bor-der. Mylohyoid terminals were sparse, most prominent in interpolaris, and occupied only dorsolateral TBNC regions and laminae III and IV of C1–C3. The auriculotemporal innervation of the mandibular TBNC was heaviest in interpolaris and was restricted to mostly ventrolateral regions. Its primary focus, however, was laminae III and IV of C1–C4. The clinical implications of this topographical organization are discussed, particularly with respect to the rostrocaudal intradivisional lamination in caudalis and the cervical dorsal horn.

Suppression of postoperative pain by preoperative administration of ibuprofen in comparison to placebo, acetaminophen, and acetaminophen plus codeine

Abstract: The analgesic effect of preoperatively administered ibuprofen was evaluated in 107 dental outpatients undergoing the removal of impacted third molars. Subjects were given 800 mg ibuprofen prior to the procedure and 400 mg ibuprofen 4 and 8 hours later. Comparison was made to groups receiving either placebo at all three doses, 600 mg acetaminophen administered on the same schedule, or preoperatively administered placebo followed by two doses of postoperatively administered 600 mg acetaminophen plus 60 mg codeine. Ibuprofen pretreatment resulted in significantly less pain than placebo or acetaminophen pretreatment as the local anesthetic wore off. Ibuprofen also resulted in less postoperative pain than acetaminophen plus codeine following the second dose. Side effects were similar across drug treatments and placebo with the exception of greater reports of drowsiness following the opiate-analgesic combination. These findings indicate that pretreatment with a nonsteroidal antiinflammatory drug, such as ibuprofen, results in a suppression of postoperative pain when compared to standard therapy without an increase in side effects.

Internal deletion in a collagen gene in a perinatal lethal form of osteogenesis imperfecta.

Abstract: Cloned probes specific for unique genes have proven to be powerful tools in defining the nature of genetic diseases such as the thalassaemias and growth hormone deficiencies. A similar approach should be useful in defining heritable diseases of type I collagen, the heterotrimer of two alpha 1(I) chains and one alpha 2(I) chain, which is the most abundant member of the collagen family of proteins. Recently, cloned cDNAs and genomic DNAs for the two polypeptide chains of the type I collagen have become available and have been used to elucidate the chromosomal location of the corresponding genes. Here, we have used several of these cloned DNAs to demonstrate the presence of an internal deletion of about 0.5 kilobases (kb) in one allele for the pro alpha 1(I) chain in a patient with osteogenesis imperfecta (OI), a group of heritable disorders which are characterized by brittle bones but which are highly heterogeneous both phenotypically and biochemically.

Ganglioside‐Induced Neuritogenesis: Verification That Gangliosides Are the Active Agents, and Comparison of Molecular Species

Abstract: Gangliosides were previously reported to induce neuritogenesis in primary neuronal cultures and in some neurally derived cell lines. Because isolated gangliosides usually contain variable quantities of peptides, we investigated the possibility that neurite-stimulating activity could be caused by these contaminants. Ganglioside preparations from bovine brain and other sources were subjected to a three-step purification procedure that eliminated at least 95% of the contaminating peptides. These purified preparations retained their capacity to induce extensive neurite growth in neuro-2A murine neuroblastoma. Proteolytic digestion and a number of additional procedures were used to reduce residual contamination further without loss of activity. Several crude ganglioside samples had negative effects on neurite development until freed of their inhibitory factors, which were derived from the tissue and/or introduced during laboratory operations. This was particularly evident for bovine white matter gangliosides whose activity increased in proportion to peptide removal. When carefully purified, virtually all of 11 different gangliosides tested were highly active, with the possible exception of GM4, which demonstrated only moderate activity in a limited number of tests. All of the neutral glycolipids tested, as well as sulfatides and free sialic acid, were inactive.

Vitamin D-dependent calcium-binding protein in rat brain: biochemical and immunocytochemical characterization.

Abstract: Immunoreactive calcium-binding protein (CaBP) has been characterized in rat brain both biochemically and immunocytochemically. In this study antiserum to chick CaBP was used to characterize this protein and to describe its distribution in neurons and fibers of the rat fore- and midbrain. Immunostaining in neuronal elements was judged specific for this protein by the absence of staining in tissue sections after adsorption of the antiserum with either chick intestinal CaBP or the 28,000-dalton fraction from rat brain, but not with other molecular weight fractions with calcium-binding activity. Immunoreactive CaBP was found to have a widespread distribution throughout the central nervous system, and was present in most but not all major neuronal cell groups and fiber tracts. The protein was limited primarily to neuronal elements and some ependymal cells, and was absent in glia and blood vessels. The proportion of immunoreactivity in neuronal perikarya and fibers varied among nuclei and within a given structure at different rostral-caudal levels. Immunoreactivity was prominent in neocortex, hippocampal formation (primarily in CA1 and granular cells of the dentate gyrus), hypothalamus, and amygdala. These areas are responsible for the regulation of a variety of pituitary hormones, and several bind steroids. Immunoreactive CaBP was also a major constituent of nonlimbic system pathways. The widespread distribution of immunoreactive CaBP in the central nervous system suggests that CaBP and the vitamin D endocrine system may play a significant role in the regulation of mammalian brain function.

Miocene Hominoid Postcranial Morphology

Abstract: It is not the purpose of this chapter to provide definitive answers to any of the questions asked in its title, even though various aspects of these questions have formed a large part of the lively debate that has been conducted in recent years concerning Miocene hominoid postcrania. The material available for investigation has been increased significantly recently by new specimens from the early Miocene of East Africa [KNM-RU 2036C and KNM-RU 5872 specimens (Walker and Pickford, this volume, Chapter 12)], the later Miocene of Rudabanya, Hungary [Rud specimens (Morbeck, this volume, Chapter 14)], and the Potwar Plateau of Pakistan [most GSP specimens (Pilbeam et al., 1980)]. The main purpose of this chapter is to make some general comments on functional features of the morphology of some Miocene hominoid postcrania and on possible positional capabilities consistent with those features. Similarities to and differences from features of Miocene species evident in the postcrania of groups of living higher primates will be made purely in terms of function. Attention will be directed toward the larger bodied Miocene hominoids. Original specimens of all the East African and Asian material have been examined. The European material has been examined in cast form.

Type ii collagen‐induced arthritis Studies with Purified Anticollagen Immunoglobulin

Abstract: Immunization of rats with native bovine type II collagen results in a polyarthritis by day 21 in approximately 40% of the rats. Sera of these rats contained anticollagen IgG, principally IgG2a. Small amounts of IgG2b were also detected, but IgG1 and IgG2c were absent. By enzyme-linked immunosorbent assay, the paw tissue of these polyarthritic rats was shown to contain anticollagen IgG, the principal subclass being IgG2a, with minor amounts of IgG2b. Immunofluorescence examination of the paws from polyarthritic rats demonstrated deposition of both IgG and C3 on the articular surface. Passive transfer of disease was accomplished by injection of affinity-purified anticollagen immunoglobulin into naive recipients; paw swelling and histopathologic changes were detected 24 hours after transfer, and by immunofluorescence techniques IgG and C3 deposits were demonstrable on the articular cartilage. On passive transfer, neutrophils invaded the joint space and became juxtaposed to the surface of the articular cartilage. Passive transfer of the disease with anticollagen immunoglobulin was unsuccessful after rats were decomplemented with cobra venom factor; immunofluorescence demonstrated IgG but not C3 on the articular cartilage of these decomplemented rats. In rats decomplemented with cobra venom factor, neutrophils did not accumulate in the joint and erosion of articular cartilage was not detected.

The family and the child with epilepsy.

Abstract: Reports documenting psychosocial epiphenomena of chronic illness in individuals with that illness have been common in recent years. Few studies, however, have been concerned with how illness might affect the family. Those that have appeared in the literature often lack critical controls (i.e., control groups) and often fail to investigate possible links between illness-specific variables (i.e. chronicity, inhibition of mobility) and psychosocial outcomes on the family. The present study of 45 families focused on how children with epilepsy affect their families' functioning relative to families with a child with diabetes and families with no chronically ill members. The results suggest several areas of child and family adjustment (i.e. child self-concept, family communication, family cohesion) in which the families of epileptic children have great difficulty. Implications of these results are discussed with regard to differential influences of various chronic illnesses on families and family-based preventive and remedial treatment programs.

Kinetic Analysis of Collagen Fibrillogenesis: I. Use of Turbidity-Time Data

Abstract: A method is presented for analyzing turbidity-time curves characterizing biological assembly and disassembly processes. The method allows for the determination of apparent rate constants for the turbidity lag and growth phases of collagen fibrillogenesis. Plots of concentration/lag time versus concentration for type I collagen and concentration/(time to complete growth phase) versus concentration are shown to be straight lines. The slopes of these plots are defined as the apparent rate constants for the lag and growth phases. Activation energies are obtained from the temperature dependence of these slopes. The slopes of the growth portion of turbidity-time curves as well as the final turbidity are directly proportional to the collagen concentration. These observations are consistent with the hypothesis that the rate limiting steps for both lag and growth phases are apparent first order with respect to collagen concentration. Sample calculations based on light scattering theory suggest that the turbidimetric growth phase begins when the number of collagen molecules per unit length is greater than 100 and that the extent of fibril formation is proportional to the turbidity per unit concentration. These studies indicate that the turbidimetric lag phase involves both linear and lateral growth of collagen linear aggregates.

Alterations of microsomal monooxygenase system and carcinogen metabolism by streptozotocin-induced diabetes in rats

Abstract: The effects of diabetes on the liver microsomal monooxygenase enzymes and carcinogen metabolism have been studied in rats. Treatment with streptozotocin causes a marked enhancement in microsomal N-nitrosodimethylamine (NDMA) demethylase activity. The enhancement is due mainly to the induction of a high affinity NDMA demethylase (Km, approximately 0.05 mM) which is accompanied by the induction of a protein species with mol. wt. of 50,000. The treatment also induces aniline hydroxylase whose activity is in parallel with NDMA demethylase. Streptozotocin-induced diabetes also increases the metabolism of N-nitrosomethylethylamine but not that of N-nitrosomethylaniline or N-nitrosomethylbenzylamine. On the other hand, diabetes decreases the metabolism of benzo[a]pyrene, benzphetamine, and ethylmorphine. The result suggest that diabetes causes an alteration of the composition of cytochrome P-450 isozymes; the forms efficient in metabolizing NDMA are increased while certain other forms of cytochrome P-450 are decreased.

The Evolution of the Primate Foot from the Earliest Primates to the Miocene Hominoids

Abstract: The fossil evidence relating to the evolution of the primate foot is reviewed and evaluated. Many of the characteristic features of the primate foot had evolved by the early Tertiary over 40 million years ago. Probably the most significant of these developments was the progressive migration of the talus to a position over the calcaneum. These morphological features are followed through the Miocene hominoid genera from East Africa, Europe, and South Asia. While some features of Miocene hominoids, especially those relating to climbing abilities, are still evident in the predominantly bipedal earliest hominids of the Plio-Pleistocene, there is no evidence yet from the Miocene of the first stages in the evolution of that bipedalism.

Bilateral enucleation alters visual callosal but not corticotectal or corticogeniculate projections in hamster

Abstract: Visual callosal, corticogeniculate and corticotectal projections were examined using autoradiography and the horseradish peroxidase (HRP) technique in normal hamsters and in animals subjected to removal of both eyes at birth. The visual callosal pathway in the bilateral enucleates was markedly abnormal. The central portion of area 17 which was, for the most part, devoid of callosal cells and terminals in the normals, contained heavy callosal labelling and a large number of callosal neurons in the enucleated animals. The laminar distribution of callosal terminals in the medial part of area 17 in the enucleates was very similar to that seen near the 17-18a border in the normal animals. Label was densest in layers V and VI, light in lamina IV, and fairly dense in the supragranular layers. The laminar distribution of callosal neurons in the bilateral enucleates was, however, quite abnormal. Callosal cells were scattered, in approximately equal proportions, throughout layers II–III and V. In the normals, over 70% of all callosal neurons were in layers II–IV. The laminar origins and topography of the corticotectal and corticogeniculate projections were essentially normal in the blinded hamsters.

Glutamate Uptake and Metabolism in C‐6 Glioma Cells: Alterations by Potassium Ion and Dibutyryl cAMP

Abstract: Uptake and metabolism of glutamate was studied in the C-6 glioma cell line grown in the absence or presence of dibutyryl cyclic AMP (dbcAMP). Glutamate and aspartate uptake were competitive in cells grown under both conditions. Increased [K+] in the medium caused a significant decrease in the uptake of both amino acids. A small part of this decrease (<25%) was due to an enhanced efflux of tissue amino acid. The effects of increased [K+] were observed whether or not the [Na+] in the medium was concomitantly decreased. In cells grown in the presence of 1 mM dbcAMP for 48 h, glutamate uptake and metabolism were altered. Tissue levels of glutamate, aspartate, glutamine, GABA, and alanine were generally less in treated than in naive cells. When incubated with 50 μM [U-14C]glutamate, there was significantly less incorporation of radioactivity into treated cells with time, resulting in greatly lowered specific radioactivities of glutamate, aspartate, and GABA. However, the rate of labeling of glutamine was greatly increased; this was consistent with the previously observed doubling in glutamine synthetase activity in dbcAMP-treated C-6 cells. Tissue glutamate decarboxylase activity was halved in treated cells, accounting for the large decrease in GABA labeling. The metabolic data suggested a decreased uptake of exogenous glutamate; in studies on initial rates of uptake, the Vmax of high-affinity glutamate uptake was decreased by 40%. This decrease was of the same order of magnitude as that observed in the metabolic experiments. Thus, in this glial model, both rapid, acute changes and slower, long-term changes in neuroactive amino acid metabolism were observed. Each of these conditions mimics a stimulus of neuronal origin, and the resulting changes could modulate extrasynaptic activity of neuroactive amino acids.

Lack of clinical efficacy of chronic oral physostigmine in Alzheimer's disease.

Abstract: Ten patients with mild to severe Alzheimer's disease were treated for up to 10 months with 10 to 15 mg oral physostigmine daily or with placebo, according to a single blind, multiple crossover protocol. No clinically meaningful improvement occurred with physostigmine treatment.

Ascorbate-induced lipid peroxidation and inhibition of [3H]spiroperidol binding in neostriatal membrane preparations

Abstract: Sodium ascorbate caused an increased lipid peroxidation and a large decrement in [3H]spiroperidol binding in a rat neostriatal membrane preparation (preparation C). Both effects were greater at intermediate (0.05 and 0.5 mM) than at higher or lower ascorbate concentrations. In contrast, in another neostriatal membrane preparation (preparation A), there was no loss of [3H]spiroperidol binding and only a small increase in lipid peroxidation caused by ascorbate. However, both the ascorbate-induced increase in lipid peroxidation and loss of [3H]spiroperidol binding were greatly enhanced in preparation A by the addition of iron salts. In experiments designed to explore reasons for these apparent discrepancies, we discovered that the method of tissue preparation was a critical factor. The ascorbate effects were consistently greater in a tissue preparation which was originally homogenized in an isotonic sucrose medium and centrifuged, and the cell debris discarded (as was done in preparation C), than in one in which the tissue was homogenized in a hypotonic medium and in which no low-speed centrifugation was done (as was done in preparation A). In other experiments, of several cations tested, only ferrous and ferric potentiated the above-described effects of ascorbate. Some ascorbic acid derivatives (e.g., isoascorbic acid) had properties similar to those of ascorbic acid, whereas several reducing agents could, in the presence of added iron salts, cause both a lipid peroxidation and a loss of [3H]spiroperidoI binding. However, the other reducing agents tested (e.g., dithiothreitol) were iess potent in both regards than was ascorbate. In other experiments, several chelating agents (e.g., EDTA) or commonly used inhibitors of lipid peroxidation (e.g., propyl gallate) were able to counteract the effects of ascorbate on lipid peroxidation and on [3H]spiroperidol binding.