Mucin-producing tumor of the pancreas: diagnostic value of diffusion-weighted echo-planar MR imaging

It is generally accepted that hemifacial spasm (HFS) and trigeminal neuralgia are caused by compression of the facial nerve (seventh cranial nerve) or the trigeminal nerve (fifth cranial nerve) at the nerve's root exit (or entry) zone (REZ); thus, neurosurgeons generally perform neurovascular decompression at the REZ. Neurosurgeons tend to ignore vascular compression at distal portions of the seventh cranial nerve, even when found incidentally while performing neurovascular decompression at the REZ of that nerve, because compression of distal portions of the seventh cranial nerve has not been regarded as a cause of HFS. Recently the authors treated seven cases of HFS in which compression of the distal portion of the seventh cranial nerve produced symptoms. The anterior inferior cerebellar artery (AICA) was the offending vessel in five of these cases. Great care must be taken not to stretch the internal auditory arteries during manipulation of the AICA because these small arteries are quite vulnerable to surgical manipulation and the patient may experience hearing loss postoperatively. It must be kept in mind that compression of distal portions of the seventh cranial nerve may be responsible for HFS in cases in which neurovascular compression at the REZ is not confirmed intraoperatively and in cases in which neurovascular decompression at the nerve's REZ does not cure HFS. Surgical procedures for decompression of the distal portion of the seventh cranial nerve as well as decompression at the REZ should be performed when a deep vascular groove is noticed at the distal site of compression of the nerve.     

TANGENTIAL VELOCITY CHANGE WITH TIME OF POLYACRYLAMIDE SOLUTION IN A CONCENTRIC ANNULUS

Tangential velocity change with time of polyacrylamide solution, which had not only viscosity but also elasticity, in a concentric annulus after step motion of the inner cylinder was measured by using a LDV method. By adapting a conception of a second order lag control system which had a feedback connection, an equation for estimating the velocity change with time was presented. Each parameter in the equation was determined based on the experimental results, and the relationships between each parameter and viscosity or elasticity of the solutions was made clear. By using this equation, the tangential velocity change with time of a viscoelastic liquid in the annulus can be estimated when the viscosity and elasticity of the liquid and the rotational speed of the inner cylinder are given. Additionally, it was confirmed that the equation was applicable to the case of polyethyleneoxide solution, which had different ranges of the viscosity and elasticity from those of the test solutions described above.     

Effects of scatter and attenuation correction on quantitative assessment of regional cerebral blood flow with SPECT

The pyruvate dehydrogenase complex (PDC) plays a key role in the anaerobic mitochondrial metabolism of the parasitic nematode Ascaris suum. A cDNA coding for an A. suum pyruvate dehydrogenase kinase (APDK) has been cloned and sequenced from poly(A)+ RNA isolated from adult A. suum muscle.2 APDK exhibited significant sequence identity to mammalian PDKs. Nucleotide sequence analysis of the APDK cDNA revealed a 22-nucleotide spliced leader, characteristic of many nematode mRNAs, a 5'-UTR of 6 nucleotides, an open reading frame of 1197 nucleotides, and a 3'-UTR of 101 nucleotides that included a putative polyadenylation signal. The open reading frame predicted a protein of 399 amino acids with a molecular weight of 45,402 that included a putative 18-aminoacid leader peptide. Recombinant APDK (rAPDK) was functionally expressed in Escherichia coli with a his tag at its N-terminus and purified to apparent homogeneity on Ni-NTA-agarose. Recombinant APDK was a dimer and was not autophosphorylated and its activity was stimulated in the presence of APDK-deficient adult A. suum muscle PDC presumably by the binding of APDK to the dihydrolipoyl transacetylase (E2) core of the complex. After binding to the core, rAPDK activity was stimulated by elevated NADH/NAD+ and acetyl CoA/CoA ratios within the same ranges as observed for the native APDK. Immunoblotting suggested that native APDK focused as a series of 43-kDa spots (pI 6.1-6.8) on two-dimensional gels of the purified adult A. suum muscle PDC.     

A subcloned human esophageal squamous cell carcinoma cell line with low thrombomodulin expression showed increased invasiveness compared with a high thrombomodulin-expressing clone--thrombomodulin as a possible candidate for an adhesion molecule of squamous cell carcinoma

Inside-out vesicles of plasma membranes prepared from a plant source were used as models to investigate effects of centrifugal forces on separations of early and late endosome populations by aqueous two-phase partition. Endosome subpopulations were resolved readily by preparative free-flow electrophoresis where acidification of the interiors of late endosomes occurred upon addition of ATP to activate a proton translocating ATPase. The resultant increased diffusion potential provided for a surface difference between late and early endosomes to permit electrophoretic separation. With the plant membranes, unincubated inside-out plasma membrane vesicles modeled early endosomes, whereas inside-out vesicles incubated with 1 mM ATP modeled late endosomes. A latent, 2,4-dichlorophenoxyacetic acid (2,4-D)-(auxin)-stimulated NADH:protein disulfide reductase measured spectrophotometrically was used as an enzymatic marker for both populations of inside-out vesicles. Phase partition behavior of each population was quantitated using total protein as the parameter.     

Statistical measurements as a way to study mode partition in injection lasers

We have demonstrated a statistical measurement technique to characterize the mode partition in injection lasers. In the steady state small nonlasing side modes have distributions similar to that of a narrow-band Gaussian noise. There is a certain probability that they carry a significant portion of the total output. For example, if a side mode of a TJS (AlGa)As laser contains on the average 1.6 percent of the total output power, there is a probability of 10^-6, that it carries 30 percent of the total output. Distributions of main modes of a multimode laser can be matched by beta distributions with properly selected parameters. In addition to dc conditions, this technique has also been used to study the transient behavior of injection lasers. The dominant mode has been shown to start from a noise distribution.     

Efficacy of microwave coagulation therapy (MCT) in patients with liver tumors

We evaluated the efficacy of microwave coagulation therapy (MCT) in 84 patients with hepatocellular carcinomas (HCC) and 40 with metastatic liver tumors (MLT). The response rates calculated with diagnostic imaging were 92% in HCC and 80% in MLT. The regional recurrence rates were relatively higher in patients with MLT (33%) than in HCC (14%). The average surgical margin in operative MCT group was 11 mm. The cumulative survival rates at three and five years were 63% and 38% in HCC and 43% and 33% in MLT, respectively. The complications were similarly encountered in HCC and MLT (12% versus 13%). When these observations are taken together, MCT is a radical and safe locoregional therapy which can keep an adequate surgical margin and assure long survival.