A vital region for human glycoprotein hormone trafficking revealed by an LHB mutation.

Glycoprotein hormones are complex hormonally active macromolecules. Luteinizing hormone (LH) is essential for the postnatal development and maturation of the male gonad. Inactivating Luteinizing hormone beta (LHB) gene mutations are exceptionally rare and lead to hypogonadism that is particularly severe in males.

Injectable hydrogels with high fixed charge density and swelling pressure for nucleus pulposus repair: biomimetic glycosaminoglycan analogues.

The load-bearing biomechanical role of the intervertebral disc is governed by the composition and organization of its major macromolecular components, collagen and aggrecan. The major function of aggrecan is to maintain tissue hydration, and hence disc height, under the high loads imposed by muscle activity and body weight. Key to this role is the high negative fixed charge of its glycosaminoglycan side chains, which impart a high osmotic pressure to the tissue, thus regulating and maintaining tissue hydration and hence disc height under load.

Lubricin: Its Presence in Repair Cartilage following Treatment with Autologous Chondrocyte Implantation.

Objective: To determine if lubricin was present in the surface layer of repair cartilage formed after autologous chondrocyte implantation (ACI).

Design: Forty-three biopsies of repair tissue were taken from patients who had been treated with ACI 8 to 68 months previously (mean of 18.0 ± 14.

Immunohistochemical study of collagen types I and II and procollagen IIA in human cartilage repair tissue following autologous chondrocyte implantation.

This study has assessed the relative proportions of type I and II collagens and IIA procollagen in full depth biopsies of repair tissue in a large sample of patients treated with autologous chondrocyte implantation (ACI). Sixty five full depth biopsies were obtained from knees of 58 patients 8-60 months after treatment by ACI alone (n=55) or in combination with mosaicplasty (n=10). In addition articular cartilage was examined from eight individuals (aged 10-50) as controls.

Intervertebral disc cells as competent phagocytes in vitro: implications for cell death in disc degeneration.

Introduction: Apoptosis has been reported to occur in the intervertebral disc. Elsewhere in the body, apoptotic cells are cleared from the system via phagocytosis by committed phagocytes such as macrophages, reducing the chance of subsequent inflammation. These cells, however, are not normally present in the disc.

Bovine explant model of degeneration of the intervertebral disc.

Background: Many new treatments for degeneration of the intervertebral disc are being developed which can be delivered through a needle. These require testing in model systems before being used in human patients. Unfortunately, because of differences in anatomy, there are no ideal animal models of disc degeneration.

Combined autologous chondrocyte implantation and allogenic meniscus transplantation: a biological knee replacement.

Meniscus deficient knees develop early osteoarthritis in the knee. Autologous Chondrocyte Implantation has provided a new dimension to the treatment of chondral defects in the knee, with 85% good to excellent results and a long-term durable outcome of up-to 11 years. However, it is contraindicated in meniscus deficient knees.

Histology and pathology of the human intervertebral disc.

The intervertebral disc is a highly organized matrix laid down by relatively few cells in a specific manner. The central gelatinous nucleus pulposus is contained within the more collagenous anulus fibrosus laterally and the cartilage end plates inferiorly and superiorly. The anulus consists of concentric rings or lamellae, with fibers in the outer lamellae continuing into the longitudinal ligaments and vertebral bodies.

TNFalpha-stimulated gene product (TSG-6) and its binding protein, IalphaI, in the human intervertebral disc: new molecules for the disc.

Inflammation and irritation of the nerve roots has been indicated as an important factor in the pain associated with symptomatic disc herniations. Tumour necrosis factor alpha (TNFalpha) is now believed to be involved in this pathway. TNFalpha causes connective tissue cells in culture to synthesise a glycoprotein, TNFalpha-stimulated gene-6 (TSG-6).

Autologous chondrocyte implantation for cartilage repair: monitoring its success by magnetic resonance imaging and histology.

Autologous chondrocyte implantation is being used increasingly for the treatment of cartilage defects. In spite of this, there has been a paucity of objective, standardised assessment of the outcome and quality of repair tissue formed. We have investigated patients treated with autologous chondrocyte implantation (ACI), some in conjunction with mosaicplasty, and developed objective, semiquantitative scoring schemes to monitor the repair tissue using MRI and histology.

Increased nerve and blood vessel ingrowth associated with proteoglycan depletion in an ovine anular lesion model of experimental disc degeneration.

Study Design: Nerves and blood vessel distribution in discs were localized immunohistochemically and correlated with the proteoglycan contents of normal and degenerate disc tissues.

Objective: The aim of the present study was to systematically evaluate whether nerve and blood vessel ingrowth was associated with depletion of disc proteoglycans and degenerative changes in an established experimental model of disc degeneration.

Summary Of Background Data: Animal models of disc degeneration, allowing longitudinal study of pathogenic mechanisms, are limited.

Cells from different regions of the intervertebral disc: effect of culture system on matrix expression and cell phenotype.

Study Design: This study examined how the culture system and region of cellular origin affect disc cell morphology and extracellular matrix production.

Objective: To determine the role of the cell populations in the different regions of the adult intervertebral disc in maintaining gradients in composition across the disc.

Summary Of Background Data: It is not known whether the steep profiles in composition across the intervertebral disc are maintained by distinct cell populations or whether differences in cell metabolism are determined by changes in the physical environment across the disc.

Immunohistochemical detection of Schwann cells in innervated and vascularized human intervertebral discs.

Study Design: The ingrowth of nerves, blood vessels, and Schwann cells into human intervertebral discs was examined using immunohistochemistry for cell-type-specific markers.

Objectives: To determine whether Schwann cells may contribute to disc innervation, and to assess the relation between disc innervation and vascularization.

Summary Of Background Data: Intervertebral disc degeneration was associated previously with ingrowth of blood vessels and nerves.

Matrix turnover in human cartilage repair tissue in autologous chondrocyte implantation.

Objective: Autologous chondrocyte implantation (ACI) is a form of tissue engineering that is being used increasingly to treat damaged articular cartilage. What happens at the graft site subsequent to the transplantation of chondrocytes beneath a periosteal flap has largely remained a matter of conjecture. We examined biopsy samples from the graft site using a panel of specific antibodies to investigate the cellular mechanisms involved and to determine whether remodeling of the matrix occurs.

Matrix metalloproteinases and aggrecanase: their role in disorders of the human intervertebral disc.

Study Design: A comprehensive immunohistochemical study of matrix metalloproteinase activity in discs from patients with different disc diseases.

Objectives: To identify individual matrix metalloproteinase enzymes that could contribute to the degeneration of the matrix of the intervertebral disc, to identify the cells that produce matrix metalloproteinases (for example, the endogenous disc cells or invading cells associated with vascularisation), and to determine if "aggrecanase" contributes to degradation of proteoglycans in disc disorders.

Summary Of Background Data: Matrix disorganization and loss of substance are the most common findings in degenerate discs, and proteinase enzyme activity is one means of causing these changes.

Type X collagen in the human invertebral disc: an indication of repair or remodelling?

The short-chained type X collagen was once thought to be produced exclusively by hypertrophic chondrocytes during endochondral ossification. More recently, however, it has been found elsewhere, for example in articular cartilage. In the present study, the occurrence of type X collagen in the intervertebral disc has been investigated.

Changes in collagen cross-linking in degenerative disc disease and scoliosis.

Study Design: Biochemical study of the changes in the collagen cross-link profile of human intervertebral discs collected at surgery from patients with either low back pain associated with disc degeneration or scoliosis.

Objective: To determine whether changes occur in the collagen cross-link profile in the disc of patients with either low back pain associated with disc degeneration or scoliosis, which may well influence matrix integrity. Such changes in the cross-link profile of a tissue indicates increased matrix turnover and tissue remodeling and may have implications for the progression of these disorders.

[IgM kappa lymphoma with antisulfatide antibodies revealed by cervical motor neuropathy simulating amyotrophic lateral sclerosis].

Introduction: It is well known that polyneuropathy is associated with monoclonal IgM kappa.

Exegesis: We report the case of a 79-year-old man with lymphoma and motor neuron disease at cervical level simulating amyotrophic lateral sclerosis (ALS). Neurological deficit with inflammatory process evolved within 4 months.