Pelvic remodelling after the Chiari osteotomy. A long-term review.

Survivorship analysis of 215 medial displacement pelvic osteotomies undertaken for symptomatic, incongruent dysplasia of the hip since 1966 showed that four of every five hips had not required conversion to a total hip arthroplasty. The radiological characteristics of 86 osteotomies were evaluated at a mean of 18 years (5 to 30) after surgery which was performed at the age of 15.9 +/- 9.5 years. Revision was significantly (p < 0.05) more likely in those patients operated on after the age of 25 years. The centre-edge (CE) angle increased from 2.5 +/- 13.9 degrees before to 41.8 +/- 15.0 degrees immediately after operation. The increase in CE angle was maintained at later review (38.5 +/- 16.5 degrees). Even with severe dysplasia with a CE angle less than zero a substantial improvement in the cover of the femoral head was achieved, usually by medial shift of the lower pelvic fragment. However, the head was not invariably medialised by the osteotomy and lateral movement of the ilium was noted when the position of the joint was relatively medial before operation or when the hip was arthritic. In the longer term pelvic remodelling did not reverse the medialisation produced by the osteotomy, and the cover of the femoral head was maintained.

Low intensity pulsed ultrasound stimulates osteogenic activity of human periosteal cells.

The effect of low intensity pulsed ultrasound on human periosteal cells was investigated. Normal human periosteum was obtained to culture the periosteal cells. After characterization, cultures of periosteal cells at Days 2 and 4 were treated with ultrasound for 5, 10, and 20 minutes respectively. Assessments were done to assess total number of viable cells, cell proliferation, alkaline phosphatase activity, osteocalcin secretion, vascular endothelial growth factor expression, and calcium nodule formation. With the cells not treated with ultrasound as the control, the results showed that ultrasound did not affect the total number of viable cells. It stimulated cell proliferation at the early phase of cell culture. The activity of alkaline phosphatase was increased significantly in the culture at Day 4. A similar effect was seen with osteocalcin secretion and the responses were dose-dependent. The vascular endothelial growth factor secretion increased in Day 2 and Day 4 cultures with the dose-dependent effect. Formation of calcium nodules was significantly higher with ultrasound treatment. We think that low intensity pulsed ultrasound stimulated periosteal cell proliferation and differentiation toward osteogenic lineage. The dose-dependent effect on osteogenic activities may modify the existing treatment regimen. Ultrasound treatment should be started from the beginning of fracture healing.

Renal impairment in patients with multiple myeloma.

OBJECTIVES: To determine the incidence of multiple myeloma in the Eastern District of Hong Kong Island, the degree of renal impairment at presentation, and its relationship with haematological and biochemical parameters and survival. DESIGN: Retrospective study. SUBJECTS AND METHODS: Patients with myeloma who were admitted to a regional hospital in Hong Kong from January 1994 to March 2000 were included. Demographic data, type and stage of multiple myeloma, degree of renal impairment, haematological and biochemical parameters, and survival data were analysed. RESULTS: There were 64 patients (28 male, 36 female) in the study. The incidence rate for multiple myeloma in this group was 1.78 per 100 000 population. Immunoglobulin G (53.1%) was the most common type of multiple myeloma seen, followed by immunoglobulin A (29.7%), light-chain (12.5%), and immunoglobulin D (4.7%). Nineteen (29.7%) patients had serum creatinine levels of greater than 177 micro mol/L at presentation. Renal impairment was more common in patients with light-chain multiple myeloma (P=0.081). The serum creatinine level was not significantly correlated with haemoglobin level (r= -0.21), platelet count (r=0.04), serum calcium level (r=0.08), or albumin level (r= -0.03). The median survival time for patients with multiple myeloma was 592 days (95% confidence interval, 229-955). Serum creatinine level at presentation was significantly associated with survival (P=0.017). Patients with a creatinine level of less than 400 micromol/L had longer survival (P=0.042). Infection was the most common cause of death (32.8%). CONCLUSION: The incidence rate noted was comparable to other published studies. Renal impairment at presentation was common in patients with multiple myeloma and was associated with poor survival.

Transmission light microscopy of structurally colored semithin cartilage sections.

Conversion of osmified tracheal cartilage constituents into an array of laminar interference gratings has been attained by three tandem reactions. Oxidation of semithin, LR white-embedded cartilage sections by acetic anhydride in dimethyl sulfoxide is the first step in the conversion process. Subsequent addition reactions of oxidized cartilage pyranoses and furanoses with thiocarbohydrazide constitutes the second step. Reduction of silver proteinate by thiocarbohydrazones and the concomitant coating of cartilage constituents with silver gratings completes the conversion of cartilage sections into a system of layered interference filters. In transmitted light, all components of converted cartilage display vivid structural colors, which allow detailed microscopic analysis of structurally colored cellular and extracellular cartilage constituents.

Cryopreservation of articular cartilage. Ultrastructural observations and long-term results of experimental distal femoral transplantation.

Ultrastructural changes associated with the freeze-preservation of human articular cartilage have been investigated and related to changes in transplanted distal femoral allografts in nonhuman primates. Human osteoarticular specimens were frozen at 2 degrees/minute in the presence of 15% glycerol and kept in liquid nitrogen freezers (vapor phase) from one day to two years. Ultrastructural changes were confined primarily to chondrocytes and were related to the freezing phenomenon, not to the time of storage. The cartilage matrix was affected little, explaining why articular cartilage initially survives clinical transplantation, but later undergoes degenerative changes. Osteoarticular allografts of baboons were frozen in an identical fashion to the human articular cartilage and transplanted into adult baboons. Long-term observations (five years) on these animals showed healing and replacement of the osseous portion of cryopreserved allografts. Fractures that appeared to coincide with maximum revascularization of the graft were the principal complication. Articular surfaces of the cryopreserved allografts underwent degenerative changes over five years. These degenerative changes were also manifested radiologically and appeared similar to those observed in humans. By contrast, fresh osteoarticular allografts healed poorly through fibrous union. However, in one of two fresh allografts, the articular cartilage remained intact five years after transplantation.

Lead tetraacetate-thiocarbohydrazide-silver proteinate method for light microscopy of polysaccharides.

Lead tetraacetate-thiocarbohydrazide-silver proteinate reaction sequence for light microscopy of polysaccharides was evaluated on Carnoy's fixed rat liver sections. The results of this evaluation suggest that, on the light microscopic level, the lead tetraacetate-thiocarbohydrazide-silver proteinate method may serve as a practical and histochemically specific alternative to the lead tetraacetate-Schiff reaction for the localization of tissue carbohydrates.

Turnover of phospholipids in HUT 102 lymphoblasts and chromatographic characterization of purified lecithins after their exposure to long-wave UV light, psoralen, and UV light and psoralen.

The turnover of 32P-labeled phospholipids in HUT 102 lymphoblasts was determined after a 2 h interaction of lymphoblasts with 8-methoxypsoralen (8-MOP) (15 micrograms ml-1), longwave UV light (UVA) irradiation and PUVA (8-MOP and UVA). In parallel experiments, micellar suspensions of lyso-phosphatidylcholine (PtdC), dipalmitoyl-PtdC and dilinoleoyl-PtdC, treated in a similar manner, served for the correlative assessments of cellular lipid changes. The dark reaction, UVA irradiation and PUVA all depressed total phospholipid levels in HUT 102 cells, although only PUVA induced a statistically significant decline. Thin layer chromatography (TLC) analysis revealed that neither UVA nor 8-MOP alone triggered any significant changes in the cellular content of phosphatidylinositol (PtdI), phosphatidylinositol 4-monophosphate (PtdIP) and phosphatidylinositol 4,5-bisphosphate (PtdIP2), whereas the lyso-PtdC and PtdI content of lymphoblasts showed a two-fold increase after PUVA. The TLC analysis of lyso-PtdC and micelles of dipalmitoyl-PtdC did not reveal any detectable changes after the dark reaction with 8-MOP, UVA irradiation and PUVA. In contrast, the derivatives of dark and UVA mediated reactions of 8-MOP with dilinoleoyl-PtdC were detected by TLC. These results suggest that the formation of 8-MOP derivatives of cellular phospholipids effected by PUVA, modulates the turnover of phosphoinositides and the rate of cellular proliferation.

Cytometric and electron microscopic studies of the direct interaction of divalent nickel with intact and chemically modified HuT-78 lymphoblasts.

Cytometric and ultrastructural studies on 24 hr cultures of intact, 1.0 mM H5IO6, and 0.1 mM SeO2-oxidized HuT-78 lymphoblasts were performed after their direct, 30 min interaction with 1.0 mM NiCl2. Except for moderately depressed cell viability, divalent nickel did not alter the progression of intact and oxidized target cells through the phases of the cell cycle. Although the plasma membrane remained structurally intact, marked distortion of mitochondria structure and increased osmiophilia were an invariable attribute of all nickel-pulsed cells. Moreover, numerous electron-opaque, intracellular depositions were detected in SeO2-oxidized, nickel-pulsed cells. It is concluded that the initial state of plasma membrane, and the interaction of nickel with other trace elements, have jointly determined the response of HuT-78 cells to brief and direct, divalent nickel pulses.

Ultrastructural modification of the plasma membrane in HUT 102 lymphoblasts by long-wave ultraviolet light, psoralen, and PUVA.

Ultrastructural alterations of the plasma membrane in HUT 102 lymphoblasts were assessed after a 2-h interaction with a suprapharmacologic (15 micrograms/ml) concentration of 8-MOP, 2-h irradiation with UVA (2.1 mW/cm2), and the exposure of the HUT 102 cells to PUVA under the same conditions. The dark reaction of HUT cells with 8-MOP resulted in the disappearance of microvilli, the emergence of plasma-membrane-associated spherical bodies, formation of lamellar fungiform membrane evaginations, and, in approximately 1% of the cells, formation of uropods and cell capping. Except for uropod formation and cell capping, UVA has induced the same plasma-membrane alterations, and was more deleterious to structural cytoplasmic integrity than 8-MOP. Morphologic changes of the plasma membrane in PUVA-exposed cells tended to replicate structural alterations elicited independently during the dark reaction by suprapharmacologic 8-MOP concentrations. Partial retention of microvilli by cells after PUVA was the sole exception. In light of all available evidence we conclude that psoralen during the dark reactions interacts with plasma membrane lipids by as yet undisclosed mechanisms and that in addition to lipids, membrane proteins are also the primary target of the initial interaction of HUT 102 cells with psoralen during PUVA treatment.

Ultrastructural cytochemistry of hepatic lysosomes and their protein components is selectively revealed by the ninhydrin-dimethyl sulfoxide-thiocarbohydrazide-silver proteinate reaction.

Proteins in lysosomal membranes, lysosomes and within the transtubular network are readily accessible for electron microscopic analysis by a new three-step method. Oxidative deamination of tissue-bound amino acids by ninhydrin in aqueous dimethyl sulfoxide and the concomitant formation of corresponding carbonyl groups comprise the first step. The addition reaction of thiocarbohydrazide to tissue-bound carbonyl groups comprises the second step, while the reduction of silver proteinate by tissue-bound thiocarbohydrazones is the final step of this sequential method. Glutaraldehyde-fixed and osmified ultrathin sections of rat liver embedded in LR White were oxidatively deaminated for 24 h by 1% w/v ninhydrin in aqueous 75% v/v dimethyl sulfoxide (DMSO). They were then incubated for 40 min in aqueous 1% w/v thiocarbohydrazide (TCH) and stained for 30 min at 50 degrees C with silver proteinate (SP). The ninhydrin-dimethyl sulfoxide-thiocarbohydrazide-silver proteinate (N-DMSO-TCH-SP) reaction proved to be chemically specific and highly selective for ultrastructural resolution of the internal structure of lysosomes and their protein components. We conclude that the N-DMSO-TCH-SP reaction is the method of choice for cytochemical elucidation of the protein ultrastructure of lysosomes and their enzymatic aggregates.

Localization of carbohydrates in thick and ultrathin LR white-embedded tissue sections oxidized by acetic anhydride in dimethyl sulfoxide.

The applicability of acetic anhydride (AA) in dimethyl sulfoxide (DMSO) for the oxidation of polysaccharide and their subsequent visualization with thiocarbohydrazide (TCH) and silver proteinate (SP) was evaluated on LR White-embedded thick and ultrathin liver sections. The results of these studies indicated that AA-DMSO-TCH-SP reaction is chemically specific on LR White-embedded tissues and that it offers distinct advantages for the localization of minute glycogen aggregates.

Periodic acid-induced blastogenesis of lymphocytes is independent of phosphoinositide turnover.

The blastogenic transformation of lymphocytes by periodic acid was investigated to determine if blastogenesis induced by this mitogen was preceded by phosphoinositide turnover as previously shown for the lectins. Although periodate oxidation stimulated nucleic acid synthesis and interleukin-2 production, no changes in phosphoinositide turnover could be detected when compared to control lymphocyte cultures. These data indicate that increased phosphoinositide turnover is not an absolute prerequisite for lymphocyte proliferation.

Isolation of Thy-1 caps and analysis of their phospholipid composition in mouse T-lymphoma cells.

In this study we have used a density perturbation method to isolate anti-Thy-1 antibody-induced Thy-1 caps from mouse T-lymphoma cells in the absence of detergents, and then compared the phospholipid composition of these capped membranes with that of uncapped membranes. Initial phospholipid analysis by two-dimensional thin layer chromatography (2-D TLC) reveals a significant increase in the amount of 32P-labeled phosphatidylcholine in the Thy-1 capped membrane. In contrast, no significant changes are observed in the labeling of phosphatidylserine, phosphatidylethanolamine, or the sphingomyelins. Therefore, it is suggested that phosphatidylcholine may be involved in the organization and/or regulation of Thy-1 antigen redistribution. The composition of phosphoinositide in uncapped and capped membranes was analysed separately using one-dimensional thin layer chromatography (1-D TLC) to resolve phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PlP), and phosphatidylinositol 4, 5-bisphosphate (PIP2) from all other phospholipids. This analysis reveals a significant reduction in levels of PIP and PIP2, but not PI, in Thy-1 caps. Through the use of ion exchange column chromatography, we have found an increased production of all three species of inositol phosphates during anti-Thy-1 antibody-induced capping. Inositol 1, 4, 5-triphosphate (IP3) shows the most significant increase, compared to the much smaller increases in inositol 4, 5-bisphosphate (IP2) and inositol monophosphate (IP). These results suggest that the binding of anti-Thy-1 antibody to Thy-1 antigen activates phospholipase C which, in turn, initiates polyphosphoinositide turnover and IP3 production. It is proposed that these observed effects are the result of early signal transducing events which are prerequisite steps in Thy-1 receptor cap formation.

A modified periodic acid-thiocarbohydrazide-silver proteinate staining sequence for enhanced contrast and resolution of glycogen depositions by transmission electron microscopy.

Oxidation of araldite-embedded liver sections by 1% w/v aqueous H5IO6 for 15 min and a 5-min reaction of carbonyls with 1% w/v thiocarbohydrazide in 10% v/v acetic acid was employed for subsequent staining of glycogen with silver-proteinate (S-P). The network of branching intracellular glycogen aggregates was revealed by 15-min staining with S-P, whereas 24 hr incubation in S-P was necessary to enhance the contrast of glycogen inclusions. We conclude that the proposed modification of glycogen staining readily affords the means for its localization at a desired level of contrast and resolution.

Ultrastructural alterations in Tetrahymena pyriformis induced by growth on saturated phospholipids at 40.1 degrees C.

Structural changes in Tetrahymena pyriformis, strain WH-14, induced by growth on saturated phospholipids at 40.1 degrees C, uere studied by electron microscopy. Alterations in the ultrastructural organizations of the cell membrane and surface regions were common. These alterations were characterized in the displacement of kinetosomes, the spatial disorientation and disorganization of cortical ridges and grooves, and the spatial disorientation of longitudal and transverse microtubular ribbons. Irregular surface protrusions and multiple invaginations of alveolar membranes were among the most common features encountered. Disorganization of longitudinal microtubular ribbons was also a frequent encounter. The integrity of the ultrastructure of cell surface membranes and of the internal organization and ultrastructure of the kinetosomes, however, appeared to be unaltered. Other alterations included those of a number of cytoplasmic organelles (e.g. mitochondria and endoplasmic reticulum), which showed characteristic changes in the structural patterns.