Transdural spinal cord herniation: imaging and clinical spectra

OBJECTIVE: Many diseases induce asymmetric delays in the visual pathway, resulting in a spontaneous Pulfrich phenomenon (PP). The PP is a visual stereoillusion that may cause difficulties in persons when traveling in cars, crossing the road, or playing ball games. The authors developed and tested a simple new bedside procedure to detect PP. DESIGN: A case series. PARTICIPANTS: Disease simulation in 2 normal subjects and 18 patients with optic neuritis (ON) was examined. Ninety normal subjects were studied to determine normal range of PP. INTERVENTION: The new test, called swinging pen test (SPT), is performed by oscillating a pen by hand. The SPT was compared to a gold standard, a mechanical pendulum (MP). MAIN OUTCOME MEASURES: The authors measured simulated PP in two normal subjects and PP in 18 patients with ON and 90 normal control subjects. The Pearson product-moment correlation (r) and the Spearman rank correlation (rs) between SPT and MP were calculated. RESULTS: The magnitudes of simulated PP determined with the SPT and the MP correlated well (r = 0.92, P < 0.005, and r = 0.96, P < 0.001). Correlation also was good in patients with ON (rs = 0.90, P < 0.05). The positive predictive value of the SPT was 100%, and the negative predictive value was 92%. The PP was absent in all control subjects testing with either pendulum. The normal range for PP varied from -1.40 to 1.52 msec. For the SPT, the intraobserver variability coefficient was 8.2%, and the interobserver variability coefficient was 10.5%. CONCLUSIONS: The authors believe that SPT will be of value to clinicians on bedside evaluation of motion stereopsis dysfunctions. The normal range of PP was approximately +/- -1.5 msec (approximately +/- -1.5 cm), corresponding to a 0.3-log unit neutral density filter).     

Exfoliation syndrome in a 17-year-old girl

A 17-year-old girl with unilateral congenital glaucoma who had undergone trabeculectomy and peripheral iridectomy in infancy developed apparent exfoliation syndrome (XFS) in the eye that underwent the surgical procedures. A conjunctival biopsy was performed and the specimen was fixed in 2.5% glutaraldehyde, embedded in epoxy resin (Epon-Araldite, Electron Microscopy Sciences, Fort Washington, Pa), and processed for routine electron microscopy and immunostaining for elastin. Results of ultrastructural study showed scattered fibrillar aggregates compatible with those of XFS in an older adult, differing chiefly in sparsity of granular interfibrillar matrix. The XFS fibers were closely associated with elastic fibers and microfibrils. Elastosis of the actinic-aging type was somewhat greater than expected for age. To our knowledge, this is the youngest patient described with characteristic ocular findings of XFS to date, supporting others who have suggested an association between iris surgery in youth and early onset XFS. Electron microscopy was essential in ruling out the possibility of a clinically similar entity caused by ultrastructurally different material.     

Does the photon-diffusion coefficient depend on absorption?

We investigate the controversy over the precise form of the photon diffusion coefficient and suggest that it is largely independent of absorption, i.e., Do = v/3mu(s)'. After presentation of the general theoretical arguments underlying this assertion, Monte Carlo simulations are performed and explicitly reveal that the absorption independent diffusion coefficient gives better agreement with theory than the traditionally accepted photon diffusion coefficient, D(mu)a = v/3(mu(s) + mu(a)). The importance of resolving this controversy for the proper characterization of the material optical properties is discussed.     

Induction of native protein reactive antibodies by immunization with peptides containing linear B-cell epitopes defined by anti-porcine ZP3 beta monoclonal antibodies

To identify pertinent target epitopes for contraceptive vaccine development, rabbit polyclonal antibodies were raised against four peptides synthesized from the deduced amino acid (aa) sequence of porcine zona pellucida macromolecule ZP3 beta and coupled to diphtheria toxoid (DT). Synthetic peptides consisted of: P1, 23-37 aa; P2, 164-179 aa with an additional C-terminal cysteine; P3, 246-263 aa with an extra C-terminal cysteine; and P4, 310-321 aa residues corresponding to pZP3 beta precursor protein. Selected sequences were based upon B cell epitopes identified previously by monoclonal antibodies. Immune sera reacted with their respective peptides and DT in an ELISA, and also recognized porcine SIZP and pZP3 beta both in ELISA and Western blot and zona pellucida of porcine oocytes in an indirect immunofluorescence assay. None of the four anti-peptide sera recognized pZP3 alpha in Western blot, emphasizing the specificity of these antibodies to pZP3 beta. The anti-peptide sera, individually, failed to inhibit in vitro attachment of boar sperm to antibody treated zona encased porcine oocytes. However, combinations of immune sera against peptides such as P1 + P4, P2 + P4 and P1 + P2 + P4, did significantly inhibit porcine sperm-oocyte interaction. These results identify combinations of peptides that could potentially be used in the design of an immunocontraceptive vaccine based upon synthetic peptides corresponding to pZP3 beta or its homologues in other species.     

Image processing with VLSI

The development and implementation of systems for the more complex realtime image processing and scene understanding tasks, such as robot vision and remote surveillance, calls for faster computation than that possible using the traditional serial computer. The advent of VLSI has made feasible the consideration of more specialized processing architectures, designed to support these datarates, while keeping systems compact and relatively cheap. Two approaches are discussed: the use of a programmable processor array, and the customizing of image processing algorithms in silicon. This paper examines designs based upon each approach in the light of the techniques and constraints of VLSI. In particular we describe in some detail an example of a VLSI parallel array processor, the Grid (GEC rectangular image and data processor), and a number of special-purpose CMOS/SOS chips based on systolic design techniques.     

Study of the pulsation method for the hygienic treatment of underwear

Hygienic processing of the underwear in a device combining mechanical treatment, forced pumping of the washing solution and wringing by compressed air can be used under special conditions. The basic parameters of the engineering process have been determined, viz.: the number of washing baths, temperature of the water, time of processing, etc.     

Simultaneous bilateral extradural haematoma

A slowly invasive naevus of Ota was followed for 50 yrs. During this time multiple biopsies were considered to be benign cellular blue naevus. The left globe, orbit, frontal bone and meninges were excised to achieve clearance.     

Subcellular localization of prostaglandin endoperoxide H synthases-1 and -2 by immunoelectron microscopy

Prostaglandin endoperoxide H synthases-1 and -2 (PGHS-1 and -2) are the major targets of nonsteroidal anti-inflammatory drugs like aspirin and ibuprofen. These enzymes catalyze the committed step in the formation of prostanoids from arachidonic acid. Although PGHS-1 and -2 are similar biochemically, a number of studies suggest that PGHS-1 and PGHS-2 function independently to form prostanoids that subserve different cellular functions. We have hypothesized that these isozymes may reside, at least in part, in different subcellular compartments and that their compartmentation may affect their access to arachidonic acid and serve to separate the functions of the enzymes. To obtain high resolution data on the subcellular locations of PGHS-1 and -2, we employed immunoelectron microscopy with multiple antibodies specific to each isozyme. Both PGHS-1 and -2 were found on the lumenal surfaces of the endoplasmic reticulum (ER) and nuclear envelope of human monocytes, murine NIH 3T3 cells, and human umbilical vein endothelial cells. Within the nuclear envelope, PGHS-1 and -2 were present on both the inner and outer nuclear membranes and in similar proportions. Western blotting data showed a similar distribution of PGHS-1 and -2 in subcellular fractions, and product analysis using isozyme-specific inhibitors suggested that both enzymes generate the same products in NIH 3T3 cells. Thus, we are unable to attribute the independent functioning of PGHS-1 and PGHS-2 to differences in their subcellular locations. Instead, the independent operation of these isozymes may be attributable to subtle kinetic differences (e.g. negative allosteric regulation of PGHS-1 at low concentrations of arachidonate (500-1000 nM)). A further conclusion of importance from a cell biological perspective is that membrane proteins such as PGHS-1 and -2, which are located on the lumenal surface of the ER, are able to diffuse freely among the ER and the inner and outer membranes of the nuclear envelope.     

An evaluation of the prognostic significance of antigen CD95(Fas/APO-1) expression on the cells of patients with a myelodysplastic syndrome, acute myeloid leukemia and chronic myeloleukemia

AIM: The expression of CD95(Fas/APO-1) antigen was studied on bone marrow cells of 19 MDS patients, peripheral blood blast cells of 15 acute myeloid leukemia (AML) patients, blast cells and granulocytes of 68 patients with chronic myeloid leukemia (CML)--24 in chronic, 9 in accelerated phase and 35 in blastic crisis (BC)--by indirect surface immunofluorescence assay using flow cytometry (FACScan, Becton Dickinson, USA). RESULTS: CD95(Fas/APO-1) antigen was revealed on bone marrow cells of 8 out of 19 (36.8%) MDS patients; the percentage of antigen-positive cells was 38.1 +/- 19.2%; on 45.5 +/- 22.8% of cells in 6(45%) of 15 AML patients. Fas/APO-1 antigen was totally absent in CML chronic stage; its expression was found in 34% (12 of 35) of our patients with CML BC on peripheral blood blasts and in 56% (5 of 9) on peripheral blast cells of CML patients in acceleration phase. CONCLUSION: The data on overall survival of CD95-positive MDS patients suggest that the presence of Fas antigen is a favorable prognostic sign for patients with MDS. The patients from CD95-negative group represent a risk group both for survival and AML transformation. In CML BC group the survival does not depend upon Fas-antigen expression.