Bone mineral density during total contact cast immobilization for a patient with neuropathic (Charcot) arthropathy

BACKGROUND AND PURPOSE: Diabetes mellitus (DM)-related neuropathic arthropathy of the foot is a destructive bone and joint process. The effect of cast immobilization and non-weight bearing on bone loss has not been well studied. The purpose of this case report is to describe the changes in bone mineral density (BMD) of the calcaneus in the feet of a patient with acute neuropathic arthropathy during total contact cast immobilization. CASE DESCRIPTION: The patient was a 34-year-old woman with type 1 DM, renal failure requiring dialysis, and a 7-week duration of neuropathic arthropathy of the midfoot. Intervention included total contact casting and minimal to no weight bearing for 10 weeks, with transition to therapeutic footwear. Ultrasound-derived estimates of BMD were taken of both involved and uninvolved calcanei. OUTCOME: Bone mineral density decreased for the involved foot (from 0.25 g/cm(2) to 0.20 g/cm(2)) and increased for the uninvolved foot (from 0.27 g/cm(2) to 0.31 g/cm(2)) during casting. DISCUSSION: The low initial BMD and further loss during casting suggest the need for transitional bracing and a well-monitored return to full activity to minimize the risk of recurrence and progression of foot deformity.     

Evaluation of a token system for juvenile delinquents in a residential setting

The influence of a token economy in a residential treatment facility for delinquents was evaluated in three areas of behavior: (a) in-house chore performance, (b) littering in the facility, and (c) school performance as reflected in daily evaluations by teachers. Chore performance and littering were influenced favorably by the token system. School performance, however, appeared to be unaffected by the reversal of the token program. Reasons for this finding are discussed and the need underscored that existing token systems evaluate the effectiveness of their program contingencies on a regular basis.     

Physico-Chemical Characterization of the Soluble 3α-Hydroxysteroid Oxidoreductase in the Rat Testis and Prostate

The present paper describes some physicochemical properties of the soluble 3α-oxidoreductases in the rat testis and prostate, and comparison with rat epididymal 3α-oxidoreductase, published previously (Hastings & Hansson 1979). The testicular enzyme shows properties very similar to that in the epididymis (size, stability, pH optium) except for minor differences in charge (iso-electric point). The prostatic enzyme revealed a slightly higher molecular weight, and was more sensitive to heating than those in the testis and epididymis, whereas the iso-electric point was the same as that in the testis (pI-5.25). The enzymes in all tissues exhibit very similar shapes (f/fo 1.14-1.17).
The similar properties of the testicular and prostate 3α-oxidoreductases to those previously reported for that in the epididymis may indicate that these enzymes represent identical peptide chains. The small differences observed in size, temperature stability and change may be due to their presence in different environments.     

Junctional complexes in the preimplantation rabbit embryo.

The morphology and development of junctional complexes between blastomeres of the preimplantation rabbit embryo were investigated using several approaches. Electron microscopic examination of embryos stained en bloc with uranyl acetate, and the study of junction permeability using horseradish peroxidase and lanthanum nitrate provided information on structure, intermembrane spacing and permeability of the junctional complexes. In addition, the freeze fracture technique was used with day 5 and day 6 blastocysts, since the large size of these embryos facilitated use of this method. These experiments showed that although rudimentary junctions were present between blastomeres of the early cleavage stages, effective tight junctions were not present until the blastocyst stage. Electron microscopic examination of thin sections revealed apical foci of membrane approximation or "fusion" between trophoblast cells by day 4. Freeze fracturing revealed a lattice of interconnecting ridges (on the A face) and grooves (on the B face) in the apical region between trophoblast cells of the day 5 blastocyst. This lattice formed a continuous band along the apical margin of each cell, and therefore constituted a zonula occludens. The zonula occludens of the day 5 blastocyst averages 2-3 ridges per lattice, while day 6 blastocysts had lattices that averaged 5-6 ridges. Also seen in the freeze fracture replicas from the day 5 and day 6 blastocysts were local accumulations of intramembranous particles on the A face. These particles were often observed in aggregates similar to those of previously described gap junctions. It could not be determined whether these small regions of particles were true gap junctions or a possible primitive form of gap junction because the complementary pitted surfaces (B face pits) were not demonstrated.     

Parathyroid hormone-related protein and lung biology

Parathyroid hormone-related protein (PTHrP) is expressed in normal and malignant lung and has roles in development, homeostasis, and pathophysiology of injury and cancer. Its effects in developing lung include regulation of branching morphogenesis and type II cell maturation. In adult lung, PTHrP stimulates disaturated phosphatidylcholine secretion, inhibits type II cell growth, and sensitizes them to apoptosis. In lung cancer, PTHrP may play a role in carcinoma progression, or metastasis. The protein could be a useful marker for assessing lung maturity or type II cell function, predicting risk of injury, and detecting lung cancer. PTHrP-based therapies could also prove useful in lung injury and lung cancer.     

Positive perceptions held by support staff in community mental retardation services

Existing research on support staff has been focused on variables associated with stress. However, there has been little attention to the possibility that staff may also experience a number of positive outcomes or perceptions. In the present study, 101 support staff working with adults who had mental retardation completed measures of burnout and mental health and a new measure: the Staff Positive Contributions Questionnaire (SPCQ). A range of positive perceptions of their work was endorsed by participants, demonstrating that such perceptions do exist and require theoretical explanation. The SPCQ had promising internal consistency, test-retest reliability, and construct validity. Thus, further research with this instrument is warranted.     

Microglial activation precedes dopamine terminal pathology in methamphetamine-induced neurotoxicity

Previous studies have demonstrated methamphetamine (METH)-induced toxicity to dopaminergic and serotonergic axons in rat striatum. Although several studies have identified the nature of reactive astrogliosis in this lesion model, the response of microglia has not been examined in detail. In this investigation, we characterized the temporal relationship of reactive microgliosis to neuropathological alterations of dopaminergic axons in striatum following exposure to methamphetamine. Adult male Sprague-Dawley rats were administered a neurotoxic regimen of methamphetamine and survived 12 h, or 1, 2, 4, and 6 days after treatment. Immunohistochemical methods were used to evaluate reactive changes in microglia throughout the brain of methamphetamine-treated rats, with a particular focus upon striatum. Pronounced morphological changes, indicative of reactive microgliosis, were evident in the brains of all methamphetamine-treated animals and were absent in saline-treated control animals. These included hyperplastic changes in cell morphology that substantially increased the size and staining intensity of reactive microglia. Quantitative analysis of reactive microglial changes in striatum demonstrated that these changes were most robust within the ventrolateral region and were maximal 2 days after methamphetamine administration. Analysis of tissue also revealed that microglial activation preceded the appearance of pathological changes in striatal dopamine fibers. Reactive microgliosis was also observed in extra-striatal regions (somatosensory and piriform cortices, and periaqueductal gray). These data demonstrate a consistent, robust, and selective activation of microglia in response to methamphetamine administration that, at least in striatum, precedes the appearance of morphological indicators of axon pathology. These observations raise the possibility that activated microglia may contribute to methamphetamine-induced neurotoxicity.     

Mechanical hyperalgesia in rats with chronic perfusion of lumbar dorsal root ganglion with hyperglycemic solution

In diabetes, chronic systemic hyperglycemia is associated with pain and other symptoms of peripheral neuropathy. Evaluation of mechanisms causing these symptoms is complicated because of the overlap between the systemic effects of hyperglycemia and its toxic effects within the peripheral nervous system. To address this problem we developed a technique for chronic local in vivo perfusion of rat lumbar dorsal root ganglion (DRG) with a hyperglycemic solution. Osmotic pumps were filled with 30 mM glucose in physiological buffer and implanted in normal adult rats. The output of the catheter attached to the pump was positioned in a hole drilled through the right transverse process of the L₅ vertebrae to perfuse the corresponding DRG. Repetitive tests of foot withdrawal to mechanical stimuli have shown that chronic hyperglycemia localized to the L₅ DRG causes hyperalgesia in the hind limb innervated by perfused ganglion but not in the contralateral limb. Control experiments (DRG perfusion with 5 mM glucose or 5 mM glucose+25 mM mannitol solution) have shown that hyperglycemia-induced hyperalgesia can not be attributed to surgery-related injury or hyperosmolality of the ganglion-perfusing solution. These data demonstrate direct functional toxicity of hyperglycemia in the peripheral nervous system. This technique provides a new approach for in vivo study of chronic effects of physiologically active factors on DRG neuron function.     

Evaluation of the Sheffield system for identifying children at risk from unexpected death in infancy. Results from Birmingham and Newcastle upon Tyne

The "at birth" system which is used in Sheffield to identify children likely to die unexpectedly in infancy, was tested retrospectively in Birmingham (83 cases) and in Newcastle upon Tyne (56 cases). The discrimination between cases and age-matched controls was poor in both cities. Analysis of the 8 factors used in the system showed that only 2 maintained significant case/control differences in Birmingham and Newcastle. Further investigation showed that other factors from maternity records showed significant case/control differences in these cities. Although the system used in Sheffield would not be of use in a prospective prevention programme in either Newcastle or Birmingham, the possibility of evolving an "at risk" system which might apply more widely is discussed.