Preliminary results of muscle cuff cervicoplasty in the ewe for the treatment of urinary incontinence

We describe a childhood mitochondrial disorder in which the clinical symptoms began and remained confined to the gastrointestinal (GI) system during the first 4 y. Seizures heralded the onset of progressive encephalopathy at age 7. Peripheral neuropathy, retinitis pigmentosa, and neural deafness developed subsequently. Laboratory investigations disclosed elevated levels of plasma lactate, and a muscle biopsy revealed ragged red fibers lacking cytochrome c oxidase activity and diminished levels of respiratory chain enzyme complexes. Molecular genetic tests failed to show any of the previously reported pathogenic mitochondrial DNA (mtDNA) mutations. We therefore screened the whole mitochondrial genome by coupling restriction digestions with single-strand conformational polymorphism (SSCP) patterns. We identified a unique SSCP in the segment that encompassed the tRNA(Lys) gene, and direct sequencing of this segment revealed a G-->A transition at an evolutionarily conserved nucleotide at mtDNA position 8313. This G8313A transition was heteroplasmic in muscle and fibroblasts of the patient, but was absent in the white blood cells and platelets from his maternal relatives. This report illustrates how GI symptoms can be the initial manifestation in a mitochondrial disorder and suggests that mitochondrial dysfunction should be considered in differentials of unexplained chronic GI symptoms, especially when lactic acidosis or other unrelated clinical signs or symptoms are present.     

Synthesis of Allylarenes via Catalytic Decarboxylation of Allyl Benzoates

A catalyst system consisting of the palladium(0) complex Pd₂(dba)₃ and tri(p‐tolyl)phosphine was found to efficiently promote the decarboxylation of allyl benzoates with formation of allylarenes. This catalytic C O activation followed by extrusion of carbon dioxide and C C bond formation represents a sustainable alternative to traditional waste‐intensive cross‐couplings. The scope of the transformation includes allyl and cinnamyl esters of various ortho‐substituted benzoic acids. For particularly activated substrates, the palladium catalyst can optionally be replaced by an inexpensive nickel complex.

     

Cytokine regulation by virus infection: bovine viral diarrhea virus, a flavivirus, downregulates production of tumor necrosis factor alpha in macrophages in vitro

Bovine bone marrow-derived macrophages were infected in vitro with noncytopathic or cytopathic strains of bovine viral diarrhea virus. Infection with both biotypes resulted in a decreased production of tumor necrosis factor alpha upon stimulation with heat-inactivated Salmonella dublin or lipopolysaccharide. Other macrophage functions were not downregulated, indicating that the observed effect was not due to a loss in macrophage viability. The downregulated production of tumor necrosis factor alpha in infected macrophages may contribute to the well-documented immunosuppression in animals infected with bovine viral diarrhea virus.     

Nuclear detection of cellular retinoic acid binding proteins I and II with new antibodies

Apart from the retinoic acid nuclear receptor family, there are two low molecular weight (15 kD) cellular retinoic acid binding proteins, named CRABPI and II. Mouse monoclonal and rabbit polyclonal antibodies were raised against these proteins by using as antigens either synthetic peptides corresponding to amino acid sequences unique to CRABPI or CRABPII, or purified CRABP proteins expressed in E. coli. Antibodies specific for mouse and/or human CRABPI and CRABPII were obtained and characterized by immunocytochemistry and immunoblotting. They allowed the detection not only of CRABPI but also of CRABPII in both nuclear and cytosolic extracts from transfected COS-1 cells, mouse embryos, and various cell lines.     

Coherent optical pumping of semiconductor lasers

The influence of coherent optical pumping in semiconductor lasers is investigated theoretically. In particular the mathematical conditions under which an optically pumped system behaves like an electrically (incoherently) pumped system are derived. We show that it is practically impossible to reach the interesting regime where coherent effects are important because of the inherent constraints to absorb photons at the pump frequency and to reach threshold gain at the lasing frequency. The effects of changing the temperature and of reduced dimensionality are discussed     

Matrix metalloproteinases contribute to the blood-brain barrier disruption during bacterial meningitis

In this study, we investigated the involvement of matrix metalloproteinases (MMPs) in the pathophysiology of bacterial meningitis. By using an enzyme immunoassay, high concentrations of MMP-9 were detected in the cerebrospinal fluid (CSF) of adult patients with bacterial meningitis but not in controls, and in patients with Guillain-Barré syndrome. Moreover, we observed significantly elevated concentrations of the tissue inhibitor of metalloproteinase-1 (TIMP-1) in the CSF of patients with bacterial meningitis, compared with controls. In a rat model of meningococcal meningitis, intracisternal injection of heat-killed meningococci caused a disruption of the blood-brain barrier (BBB), an increase in intracranial pressure, and CSF pleocytosis paralleled by the occurrence of MMP-9 activity in the CSF 6 hours after meningococcal challenge. The MMP inhibitor batimastat (BB-94) significantly reduced the BBB disruption and the increase in intracranial pressure irrespective of the time of batimastat administration (15 minutes before and 3 hours after meningococcal challenge) but failed to significantly reduce CSF white blood cell counts. In conclusion, our results suggest that MMPs are involved in the alterations of BBB permeability during experimental meningococcal meningitis.     

Presence of matrix metalloproteinase-9 activity in the cerebrospinal fluid of human immunodeficiency virus-infected patients

To determine whether matrix metalloproteinase (MMP)-9 is a potential mediator involved in the frequently detected blood-brain barrier leakage in human immunodeficiency virus (HIV)-infected patients, zymography was used to detect MMP-9 activity in cerebrospinal fluid (CSF) samples of 80 HIV-infected patients and of 10 control patients. CSF MMP-9 activity was detected in 40% of HIV-infected patients (but not in controls) and was significantly more frequent in HIV-infected patients than in those without neurologic deficits (50% vs. 13.6%). The frequency of CSF MMP-9 activity did not significantly differ between neurologically symptomatic HIV-infected patients with or without opportunistic central nervous system disease (51.6% vs. 48.1%). Additionally, the presence of CSF MMP-9 activity in HIV-infected patients was associated with an increased CSF white blood cell count and an elevated CSF-to-serum albumin ratio, suggesting that it may play a role in blood-brain/CSF barrier leakage in HIV-infected patients.