Schwannosis: role of gliosis and proteoglycan in human spinal cord injury.

Schwannosis (aberrant proliferation of Schwann cells and nerve fibers) has been reported following spinal cord injury (SCI). In this study, we examined the incidence of schwannosis following human SCI, and investigated its relationship to gliosis. We found evidence of schwannosis in 32 out of 65 cases (48%) of human SCI that survived 24 h to 24 years after injury; this incidence rose to 82% in those patients who survived for more than 4 months.

Apoptosis after traumatic human spinal cord injury.

Object: Apoptosis is a form of programmed cell death seen in a variety of developmental and disease states, including traumatic injuries. The main objective of this study was to determine whether apoptosis is observed after human spinal cord injury (SCI). The spatial and temporal expression of apoptotic cells as well as the nature of the cells involved in programmed cell death were also investigated.

Human sympathetic preganglionic neurons and motoneurons retrogradely labelled with DiI.

The retrograde tracer 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) was used to label sympathetic preganglionic neurons (SPN) and motoneurons (MN) in postmortem human spinal cord. Seven months after microinjection of DiI into the ventral part of spinal thoracic segments T4 and T8, DiI-labelled neurons were identified and analyzed. Cryostat sections of spinal cord were prepared for light microscopy, while vibratome sections were analyzed using confocal microscopy.

The astroglial response to Wallerian degeneration after spinal cord injury in humans.

We describe the changes exhibited by astrocytes in areas of Wallerian degeneration after spinal cord injury in humans using glial fibrillary acidic protein immunohistochemistry correlated to standard histology at time points ranging from 8 days to 23 years after injury. Astrocytes were slow to react; a slight increase in immunoreactivity was observed at 4 months. Over time they began to lose immunoreactivity in both the somata and the processes as the debris from the degenerative process was cleared.

High-resolution diffusion-weighted MR of fresh and fixed cat spinal cords: evaluation of diffusion coefficients and anisotropy.

Purpose: To use high-resolution diffusion-weighted and calculated apparent diffusion coefficient (ADC) MR imaging to determine whether fixation and storage influence diffusion anisotropy in white matter tracts of cat spinal cord specimens.

Methods: Four cat cord specimens were imaged using a diffusion-weighted spin-echo sequence. Diffusion encoding was applied in the section-select axis (parallel to white matter tracts) and in the read axis (perpendicular to white matter tracts).

A model for multiple subcutaneous insulin injections developed from individual diabetic patient data.

Many diabetic patients taking multiple subcutaneous insulin injections cannot adjust their dosage appropriately to maintain blood glucose within a normal range. It is hard to predict how dosage changes and physiological fluctuations affect insulin levels and subsequently glucose control. To examine these issues, we have developed a model representing the link between dosage and blood insulin levels.

MR-pathologic comparisons of wallerian degeneration in spinal cord injury.

Purpose: To describe the MR manifestations and temporal course of wallerian degeneration that occurs above and below a spinal cord injury, and to compare the MR findings with postmortem histopathology.

Method: Twenty-four postmortem spinal cords from patients with cervical (n = 14), thoracic (n = 6), and lumbar (n = 4) cord injuries were studied with axial T1- and T2-weighted spin-echo MR imaging. Injury-to-death intervals varied from 8 days to 23 years.

Hospitalwide medication policies and standards.

The development and composition of a hospitalwide medication policies and standards manual are described. Medication policies and procedures developed independently by individual hospital departments and services at a 789-bed private teaching institution created problems related to consistency, the approval process, accreditation standards, and retrievability. Therefore, a joint nursing-pharmacy task force was formed to create a master document containing medication policies and standards for the entire institution.

Pharmacist empowerment: taking practice guidelines to the next level (Part 2).

Empowering pharmacists to have direct control and responsibility for institutional drug-use protocols can assist in reducing costs and improving the quality of patient care. This article examines pharmacist involvement in two drug use protocols in place at St. Luke's Episcopal Hospital in Houston.

Acute spinal subdural hematoma: MR and CT findings with pathologic correlates.

Purpose: To determine the MR and CT findings that characterize acute spinal subdural hematoma (ASSH).

Methods: The MR, CT, and clinical findings in three patients with surgically proved ASSH were reviewed and also correlated with the postmortem MR, CT, and cryomicrotome findings in three other patients, two with ASSH and one with an acute spinal epidural hematoma.

Results: Imaging findings in ASSH included: (a) hyperdense lesions on plain CT within the dural sac, distinct from the adjacent low-density epidural fat and silhouetted against the lower-density spinal cord and cauda equina, which it compressed; (b) lack of direct continuity with the adjacent osseous structures; (c) clumping, loculation, and streaking of blood within the dural sac on both MR and Ct; and (d) an inhomogeneous and variable signal intensity to the ASSH on all MR pulse sequences, but, nevertheless, a striking low signal intensity on T2-weighted spin-echo or T2-weighted gradient-echo to a major part of the ASSH because of deoxyhemoglobin.

Calcitonin gene-related peptide (CGRP)-like immunoreactivity in motoneurons of the human spinal cord following injury.

Changes that occur in the localization of calcitonin gene-related peptide-like-immunoreactivity (CGRP-LI) in motoneurons, following injury to the human spinal cord, were examined. CGRP-LI above and below the level of injury was compared to normal human spinal cord. Vibratome sections were cut and processed for immunostaining using the avidin-biotin immunoperoxidase method.

Acute traumatic central cord syndrome: MRI-pathological correlations.

The acute traumatic central cord syndrome (ATCCS) is commonly stated to result from an injury which affects primarily the center of the spinal cord and is frequently hemorrhagic. To test the validity of this widely disseminated hypothesis, the magnetic resonance images [MRI] of 11 consecutive cases of ATCCS caused by closed injury to the spine were analyzed and correlated with the gross pathological and histological features of 3 cervical spinal cords obtained at post mortem from patients with ATCCS, including 2 of patients studied by MRI. The MRI studies were performed acutely (18 h to 2 days after injury) in 7 patients and subacutely (3-10 days after injury) in 4.

Biological safety cabinetry.

The biological safety cabinet is the one piece of laboratory and pharmacy equipment that provides protection for personnel, the product, and the environment. Through the history of laboratory-acquired infections from the earliest published case to the emergence of hepatitis B and AIDS, the need for health care worker protection is described. A brief description with design, construction, function, and production capabilities is provided for class I and class III safety cabinets.

Risk of handling injectable antineoplastic agents.

Uptake of mutagenic substances by persons handling injectable antineoplastic agents was studied, and various methods of preventing such exposure were evaluated. Six persons who prepared i.v.