RNA splicing capability of live neuronal dendrites

Dendrites are specialized extensions of the neuronal soma that contain components of the cellular machinery involved in RNA and protein metabolism. Several dendritically localized proteins are associated with the precursor-mRNA (pre-mRNA) splicing complex, or spliceosome. Although some spliceosome-related, RNA-binding proteins are known to subserve separate cytoplasmic functions when moving between the nucleus and cytoplasm, little is known about the pre-mRNA splicing capacity of intact dendrites. Here, we demonstrate the presence and functionality of pre-mRNA-splicing components in dendrites. When isolated dendrites are transfected with a chicken delta-crystallin pre-mRNA or luciferase reporter pre-mRNA, splicing junctions clustered at or near expected splice sites are observed. Additionally, in vitro synaptoneurosome experiments show that this subcellular fraction contains a similar complement of splicing factors that is capable of splicing chicken delta-crystallin pre-mRNA. These observations suggest that pre-mRNA-splicing factors found in the dendroplasm retain the potential to promote pre-mRNA splicing.

Encephalopathy complicating high-dose melphalan

High-dose melphalan (HDM) with peripheral blood stem cell transplant (PBSCT) is a common treatment for patients with multiple myeloma (MM) and more recently also with AL amyloidosis (ALA). We report two female patients with severe renal failure who underwent treatment with HDM for MM (patient 1) and ALA (patient 2). Both patients developed severe encephalopathy with generalised tonic-clonic seizures and a Glasgow Coma Scale (GCS) of 3/15. Causes for coma such as infections, metabolic disturbances, cerebral ischaemia or haemorrhage were excluded. Patient 1 died on day 25 post transplant while comatose. Patient 2 recovered from her comatose state 18 days after transplantation. To our knowledge this is the first report on a possible role of high-dose melphalan in the development of encephalopathy.

Skeletal muscle blood flow and venous capacitance in patients with severe sepsis and systemic hypoperfusion

Alterations in peripheral vascular tone are presumed to contribute to circulatory failure during severe sepsis. Decreased venous tone with venous pooling may decrease effective circulatory blood volume, while decreased arterial tone with redistribution of systemic blood may compromise tissue nutrient flow. We compared forearm arterial and venous tone and forearm blood flow in ten patients with and ten patients without sepsis. The FVT, MVC, and FBF were measured by air plethysmography. In the septic patients, MCV was 1.4 +/- 0.1 ml compared with 3.1 +/- 0.2 ml in nonseptic patients (p less than 0.01). The FVT was 13.4 +/- 1.0 mm Hg/ml in septic patients versus 7.0 +/- 0.5 mm Hg/ml in nonseptic patients (p less than 0.01). The ratio of FBF to cardiac output was 0.28 +/- 0.07 percent in septic patients and 0.31 +/- 0.07 percent in nonseptic patients. These data suggest that increased peripheral venous capacitance and redistribution of skeletal muscle blood flow are not present in patients with sepsis.

[The effect of Solcoseryl eye gel in combination with neomycin and bacitracin on the healing of corneal lesions after foreign body removal]

The effect of Solcoseryl on the healing rate of corneal lesions after foreign body removal was assessed in a double-blind study. Solcoseryl is a protein-free hemodialysate which is widely used to stimulate tissue repair processes. The healing rate was determined by means of photodocumentation which was complete in 82 out of 92 cases. The Solcoseryl group showed in significantly faster healing rate and a lower tendency to development of corneal opacities than the control group. No side-effects were observed which could be attributed to either of the drugs used in the study.