Coil occlusion of the parent artery for treatment of symptomatic peripheral intracranial aneurysms

BACKGROUND AND PURPOSE: Peripheral intracranial aneurysms can be difficult to treat with traditional surgical or embolization techniques that spare the parent vessel. We report the results of our use of coil occlusion of the parent vessel for the treatment of nine peripheral intracranial aneurysms. METHODS: During approximately a 4-year period, nine patients (six men and three women, 27 to 68 years old; average age, 42 years) presented to our institution with peripheral intracranial aneurysms. The aneurysms were located on branches of the right posterior inferior cerebellar artery (n = 2), the right superior cerebellar artery (n = 1), the right anterior inferior cerebellar artery (n = 1), the right posterior cerebral artery (n = 3), the left middle cerebral artery (n = 1), and the left anterior cerebral artery (n = 1). Parent vessel occlusion was performed using microcoils after test injection with amobarbital (Amytal) in eight of the nine cases (one patient was comatose and could not be tested before occlusion). RESULTS: Angiography immediately after the procedure showed aneurysmal occlusion in every patient. Follow-up arteriography, performed in six patients 2 to 12 months after treatment, documented continued aneurysmal occlusion in every case. Three patients exhibited mild, nondisabling neurologic deficits after coil placement; the rest had no new deficits, although one patient was severely disabled from the initial hemorrhage and one patient died of an unrelated cause. CONCLUSION: Our results lend support to the use of parent vessel occlusion for peripheral aneurysms that are difficult to treat surgically or that are not amenable to intra-aneurysmal coil placement.     

Transplantation of cryopreserved osteochondral Dowel allografts for repair of focal articular defects in an ovine model.

The purpose of this study was to test whether successful cryopreservation of osteochondral tissue is possible and whether, with the appropriate surgical procedure, it can be used for the successful repair of focal articular defects within joints. Fresh (nonfrozen) and snap-frozen (plunged in liquid nitrogen and thawed in a water bath at 37 degrees C, repeated three times) autografts were used as positive and negative controls, respectively. Snap-frozen, frozen (fresh tissue placed in a freezer at -80 degrees C), and cryopreserved (immersed in 10% dimethyl sulfoxide for 30 minutes and then frozen at 1 degrees C/min to -80 degrees C) allografts were transplanted into the knees of adult sheep. Outcomes were evaluated 3, 6, and 12 months after transplantation. The morphological, histological, biochemical, and biomechanical behaviors and characteristics of the graft cartilage, the host cartilage adjacent to the grafts, and the opposing tibial cartilage were assessed. Freezing protocols that yielded poor chondrocyte recovery after thawing (frozen and snap-frozen) resulted in poor overall graft outcome. The cryopreservation protocol, however, resulted in intermediate recovery (50%) of chondrocytes and in intermediate overall graft outcome compared with fresh autografts. The membrane integrity of the allograft chondrocytes immediately following cryopreservation was identified as the most reliable predictor of long-term outcome of the graft. Further improvements in cryopreservation technique may lead to an effective method of banking osteochondral tissue for successful transplantation for the repair of focal defects and larger joint reconstructions.     

Primary tumor cells of myeloma patients induce interleukin-6 secretion in long-term bone marrow cultures

Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.     

“It’s all about incentive”: Social technology as a potential facilitator for self-determined physical activity participation for young people with physical disabilities

Purpose: To investigate the perceived role of social technologies in promoting physical activity participation for young people with physical disabilities and to identify design considerations that should be addressed when creating social technologies to promote physical activity. Method: Interactive design workshops for young people with physical disabilities aged 12–18 (n = 8) were held. Data were analyzed using interpretive thematic analysis. Results: Young people perceived significant benefit for social technologies to promote physical activity as they have the potential to overcome many barriers to physical activity participation. Design features recommended by the participants included (1) options for diverse interests and preferences, (2) provision of informational support, (3) support through equitable technology design, (4) incentive through competition and play, and (5) opportunities to develop community. Conclusions: Social technology has potential to provide tailored, equitable opportunities for social engagement and physical activity participation for young people with physical disabilities through needs- and preference-specific design.     

A longitudinal investigation of intimate partner violence among mothers with mental illness

OBJECTIVE: Severe mental illness, substance use, and intimate partner violence have emerged as major intersecting public health problems that adversely and disproportionately impact the lives of women in the United States. This longitudinal study investigated the demographic and clinical correlates of intimate partner violence in a sample of 324 mothers with severe mental illness. METHODS: A secondary analysis of longitudinal data was conducted by using multiple logistic regression. Participants were part of a longitudinal, community-based study of mothers with severe mental illness, which was aimed at understanding how these mothers viewed motherhood. The women were interviewed initially at baseline (interviews were conducted between 1995 and 1996) and then about 20 months later at follow-up (interviews were conducted between 1997 and 1998). RESULTS: At follow-up the prevalence rate of intimate partner violence was 19%. Multiple logistic regression analyses showed a significant positive relationship between alcohol and drug misuse at baseline and intimate partner violence at follow-up, indicating that women with a co-occurring diagnosis of a substance use disorder (dual diagnosis) were more likely than women without such a diagnosis to report intimate partner violence. The number of lifetime psychiatric hospitalizations and the number of symptoms related to psychiatric disability exhibited at baseline were positively associated with intimate partner violence at follow-up, and age was inversely associated with intimate partner violence. CONCLUSIONS: Mental health professionals serving mothers with mental health problems need to be aware of and prepared to assess the significant correlation between these intersecting public health problems in order to influence successful interventions. Particular attention must be given to the special treatment needs related to dual diagnosis and victimization and the impact of these factors on this vulnerable population.     

Trimethyltin-induced neurogenesis in the murine hippocampus

Neurogenesis continues to occur in the mature rodent brain with one of the most prominent sources for new neurons being the subgranular layer (SGL) of the dentate gyrus (DG) in the hippocampus. A number of factors can stimulate this process including synaptic activity and injury. To determine if this process would occur upon a direct injury to the dentate region, we exposed young, 21 day old male CD-1 mice to the hippocampal toxicant, trimethyltin (TMT). An acute i.p. injection of TMT (2 mg/kg) produced extensive damage and loss of dentate granule neurons within 72 h. This active period of degeneration was accompanied by an increase in the generation of progenitor cells within the SGL as identified by BrdU uptake and Ki-67 immunostaining. As additional markers for neurogenesis, both nestin and doublecortin showed increased staining patterns within the blades of the dentate. In these young weanling mice, the level of proliferation was sufficient to significantly repopulate the dentate region by 4 weeks post-TMT, suggesting a high level of regenerative potential. Our data indicate a significant level of neurogenesis occurring during the active process of degeneration and in an environment of microglia activation. The TMT-induced injury offers a model system for further examination of the process of neurogenesis, neural adaptation, and the influence of inflammatory factors and glia interactions.     

The general structure of transfer RNA molecules

The three-dimensional structure of yeast phenylalanine tRNA serves as a useful basis for understanding the tertiary structure of all tRNAs. A large number of tRNA sequences have been surveyed and some general conclusions are drawn. There are only a few regions in the molecule in which there are differences in the number of nucleotides; and the structure of yeast phenylalanine tRNA can accommodate these differences by forming or enlarging protuberances on the surface of the basic framework molecule. The nature and distribution of the differences in number of nucleotides are surveyed and possible hydrogen bonding interactions are discussed for a number of tRNA classes. The two most significant features of the molecule are the large number of stacking interactions which are seen to include most of the nucleotides in the molecule and the system of specific hydrogen bonding interactions. It is likely that these stabilizing elements are preserved in all tRNA structures.