The pig as an intermediate host for Taiwan Taenia infection

Eggs (1000-100,000/animal) of Taiwan Taenia were inoculated per os into 14 Small-Ear-Miniature (SEM), 19 Landrace-Small-Ear-Miniature (L-SEM), and 5 Duroc-Yorkshire-Landrace (DYL) pigs. These animals were sacrificed 7-107 days after infection. Thirty-four pigs were found to be infected with Taiwan Taenia cysticerci and the infection rates of SEM, L-SEM, and DYL were 86%, 89% and 100% respectively. The cysticerci recovery rates of SEM, L-SEM and DYL pigs were 27.2%, 1.7% and 0.27% respectively. Cysticerci were recovered only from the livers and none were found in muscles, viscera or other parts of the carcasses. More cysticerci were located in the liver parenchyma (71%) than on the liver surface (29%). Taiwan Taenia cysticerci were smaller than those of classical T. saginata or T. solium. Moreover, Taiwan Taenia cysticerci had 2 rows of rudimentary hooklets on the scolex. The results of this study indicate that young pigs are good intermediate hosts for Taiwan Taenia and that the SEM pig is a satisfactory host for experimental studies with this tapeworm. These results were similar to other studies with different geographic strains of the T. saginata-like tapeworm in the Far East. These strains appear to be the same and possibly a new species.     

Spectroscopic studies of lipids and biological membranes: carbon-13 and proton magic-angle sample-spinning nuclear magnetic resonance study of glycolipid-water systems.

We have obtained 1H and 13C magic-angle sample-spinning (MAS) nuclear magnetic resonance (NMR) spectra of three glycosyldiacylglycerol-water (1:1, weight ratio) mesophases, at 11.7 T, as a function of temperature, in order to probe lipid headgroup, backbone, and acyl chain dynamics by using natural-abundance NMR probes. The systems investigated were monogalactosyldiacyldiglyceride [MGDG; primarily 1,2-di[(9Z,12Z,15Z)octadec-9,12,15-trienoyl++ +]-3-beta-D-galactopyranosyl- sn-glycerol]; digalactosyldiacyldiglyceride [DGDG; primarily 1,2-di[(9Z,12Z,15Z)octadec-9,12,15-trienoyl++ +]-3- (alpha-D-galactopyranosyl-1-6-beta-D-glactopyranosyl)-sn-glycerol] ; and sulfoquinovosyldiacyldiglyceride [SQDG; primarily 1-[(9Z,12Z,15Z)octadec-9,12,15-trienoyl]-2 -hexadecanoyl-3-(6-deoxyl-6- sulfono-alpha-D-glucopyranosyl)-sn-glycerol]. At approximately 22 degrees C, all three lipid-water systems give well-resoled 13C and 1H MAS NMR spectra, characteristic of fluid, liquid-crystalline mesophases. 13C spin-lattice relaxation times of the headgroup and glycerol backbone carbons of all three materials give, within experimental error, the same NT1 values (approximately 400 ms), implying similar high-frequency motions, independent of headgroup size and charge. Upon cooling, pronounced line broadenings are observed, due to an increase in slow motional behavior. For each lipid, the onset of line broadening is seen with the glycosyl headgroup, glycerol backbone, and the first two or three carbons of the acyl chains. By approximately -20 degrees, all headgroup carbon resonances are broadened beyond detection. Both galactose moieties in DGDG "freeze out" together, implying a rigid-body motion of the disaccharide unit. Upon further cooling, the bulk polymethylene chain resonances in all three systems (in both 13C and 1H MAS) broaden greatly, followed by the olefinic and allylic carbon resonances.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hwabyung: The construction of a korean popular illness among korean elderly immigrant women in the United States

The cultural construction of Hwabyung, a Korean culture-bound syndrome, is explored among a sample of 20 elderly Korean immigrant women in the United States. Hwabyung results when distressed emotions associated with the specifically Korean way of perceiving and reacting to intolerable and tragic life situations cause bodily symptoms by interfering with the harmony of Ki (vital energy). Korean elderly immigrants report a broad range of symptoms associated with Hwabyung; they less frequently report the epigastric mass, which had been considered the cardinal symptom by cosmopolitan and traditional medical writers. Hwabyung is treated holistically with psychosocial support from family, spiritual comfort, home and popular remedies, traditional Korean medicine, and biomedical treatments. Hwabyung provides a way of conceptualizing and resolving emotional distress through somatization among Korean elderly immigrant women.     

Expression of the human retinoblastoma gene product pp110RB in insect cells using the baculovirus system

The product of the retinoblastoma susceptibility gene (RB) was overproduced in cultured insect cells using the baculovirus expression system. Upon insertion of the cloned human RB complementary DNA sequence into the viral genome downstream of the promoter of the polyhedrin gene, full-length RB protein with an apparent molecular weight of 110,000 was expressed in the insect cells. This protein was found to be phosphorylated, located in the nuclei of the infected cells, and immunologically indistinguishable from pp110RB of human cells as assayed by several anti-RB antibodies. Following cell disruption and a one-step immunoaffinity chromatographic purification, 6-12 mg of soluble pp110RB with approximately 95% purity were obtained per liter of infected suspension culture. Characterization of the two known biochemical properties of RB protein showed that this purified protein from insect cells behaved similarly to the authentic human pp110RB. First, it bound to DNA, and second, it could form a specific complex with SV40 T antigen in vitro. Prompt translocation of the protein from cytoplasm to nucleus after microinjection further indicated that the purified RB protein may be active. The availability of soluble, intact, and presumably active pp110RB in large quantity represents a significant advance for studying the biochemical and biophysical properties of the RB gene product as well as its potential biological function in cancer suppression.     

Growth inhibition of selected food-borne bacteria, particularly Listeria monocytogenes, by plant extracts

C hung , K.-T., T homasson , W.R. & W u -Y uan , C.D. 1990. Growth inhibition of selected food-borne bacteria, particularly Listeria monocytogenes , by plant extracts. Journal of Applied Bacteriology 69 , 498–503.
Six extracts from Chinese medicinal plants: Tin Men Chu, Sey Lau Pai, Siu Mao Heung, Bak Tao Yung, Kam Chin Chiu and Liao Ya, were tested for their inhibitory effect on selected food-borne bacteria by the well assay technique. Among them, Tin Men Chu, Siu Mao Heung and Sey Lau Pai inhibited the growth of Staphylococcus aureus, Klebsiella pneumonia, Escherichia coli, Shigella flexneri, Streptococcus faecalis, Salmonella paratyphi, Salm. enteritidis, Enterobacter aero-genes, Pseudomonas fluorescens, Proteus vulgaris, Alcaligenes faecalis , and three strains of Listeria monocytogenes . Two of these three extracts, Tin Men Chu and Siu Mao Heung, suppressed the growth of L. monocytogenes Scott A in cabbage juice. This inhibition was prevented by the addition of protein but not sodium chloride. Plant extracts show potential to control the growth of food-borne bacteria.     

Cell aggregation and neurite growth in gels of extracellular matrix molecules

Components of the extracellular matrix are believed to guide both nerve cells and neurites to their targets during embryogenesis and, therefore, might be useful for controlling regeneration of nervous tissue in adults. To study the influence of extracellular conditions on neurite outgrowth and cell motility, PC12 cells were suspended in three-dimensional gels containing (i) collagen (0.4 to 2 mg/mL), (ii) collagen (1 mg/mL) with added fibronectin or laminin (1 to 100 mug/mL), and (iii) agarose (7 mg/mL) with added collagen (0.001 to 1 mg/mL). Neurite outgrwoth was stimulated with nerve growth factor (NGF) and both the extent of neurite outgrowth ad cell aggregation were quantitated over 10 to 12 days in culture. The extent of neurite outgrowth was greatest at the lowest collagen concentration tested (0.4 mg/mL) and decreased with increasing concentration. The addition of laminin or fibronectin altered the extent of neurite outgrowth in collagen gels, but the differences were small. Although no neurite growth was observed in pure agarose gels, considerable neurite outgrowth occurred with the addition of small amounts (>/=0.01 mg/mL) of collagen. Mean aggregate size increased more quickly in gels with lower concentrations of collagen. For cells in 1.0 mg/mL collagen, a four- to fivefold increase in aggregate volume was seen between days 2 and 10 o the culture period, whereas the increase in DNA content during this same period was less than twofold, suggesting that the cells were aggregating, not multiplying. These results suggest that the composition of the matrix supporting nerve cells has a significant effect on both neurite outgrowth and cell motility. (c) 1994 John Wiley & Sons, Inc.     

Development and Application of Cloned DNA Probes for Clavibacter xyli subsp. xyli, the Causal Agent of Sugarcane Ratoon Stunting

Eco RI restriction fragments of genomic DNA from Clavibacter xyli subsp. xyli (CXX) were ligated with plasmid pUC18 and cloned in Escherichia coli JM109. The cloned DNA inserts from recombinant plasmids were Eco RI-excised and labeled with non-radioactive digoxigenin and used as probes. Ten specific DNA probes, RSD3, 15, 30, 31, 32, 35, 37, 41, 71, and 73 were selected for disease detection and pathogen differentiation. In the specificity tests, all of the 10 CXX DNA, probes differentiated Clavibacter xyli from other bacteria specifically. Seven out of the 10 CXX probes crossreacted with C. x. subsp. cynodontis (CXC) very weakly under moderate stringency wash conditions of hybridization. In the sensitivity tests, all of the 10 DNA probes detected the homologous DNA of CXX from 0.19 to 0.75 ng. To detect various cell numbers of CXX, the DNA probes detected 10⁴ to 10⁵ cells effectively. In Southern hybridizations, distinctly different band patterns were shown when the probes hybridized with DNA from CXX and CXC. Among these probes, RSD3, 15, 30, 31, 35, 37, and 71, efficiently detected CXX present in the sap collected from symptomless sugarcane.     

Linkage analysis of idiopathic generalized epilepsy (IGE) and marker loci on chromosome 6p in families of patients with juvenile myoclonic epilepsy: no evidence for an epilepsy locus in the HLA region.

Evidence for a locus (EJM1) in the HLA region of chromosome 6p predisposing to idiopathic generalized epilepsy (IGE) in the families of patients with juvenile myoclonic epilepsy (JME) has been obtained in two previous studies of separately ascertained groups of kindreds. Linkage analysis has been undertaken in a third set of 25 families including a patient with JME and at least one first-degree relative with IGE. Family members were typed for eight polymorphic loci on chromosome 6p: F13A, D6S89, D6S109, D6S105, D6S10, C4B, DQA1/A2, and TCTE1. Pairwise and multipoint linkage analysis was carried out assuming autosomal dominant and autosomal recessive inheritance and age-dependent high or low penetrance. No significant evidence in favor of linkage was obtained at any locus. Multipoint linkage analysis generated significant exclusion data (lod score < -2.0) at HLA and for a region 10-30 cM telomeric to HLA, the extent of which varied with the level of penetrance assumed. These observations indicate that genetic heterogeneity exists within this epilepsy phenotype.     

A Continuous Fluorescence Assay of Renin Activity

A sensitive fluorescence assay that employs a new fluorogenic peptide substrate has been developed to continuously measure the proteolytic activity of human renin. The substrate, DABCYL-gaba-Ile-His-Pro-Phe-His-Leu-Val-Ile-His-Thr-EDANS, has been designed to incorporate the renin cleavage site that occurs in the N-terminal peptide of human angiotensinogen. The assay relies upon resonance energy transfer-mediated, intramolecular fluorescence quenching that occurs in the intact peptide substrate. Efficient fluorescence quenching occurs as a result of favorable energetic overlap of the EDANS excited state and the DABCYL absorption, and the relatively long excited state lifetime of the EDANS fluorophore. Cleavage of the substrate by renin liberates the peptidyl-EDANS fragment from proximity with the DABCYL acceptor, restoring the higher, unattenuated fluorescence of the EDANS moiety. This leads to a time-dependent increase in fluorescence intensity, directly related to the extent of substrate consumed by renin cleavage. The kinetics of renin-catalyzed hydrolysis of this substrate have been shown to be consistent with a simple substrate inhibition model with a substrate K_m 1.5 μM at physiological pH; Cleavage of the substrate occurs specifically at the Leu-Val bond and corresponds to the renin cleavage site of angiotensinogen, as reported earlier. In this report, we describe in detail the synthesis of the fluorogenic renin substrate and its application in assays of renin activity. Assay sensitivity has been evaluated by a series of enzyme dilution experiments using the continuous assay format, showing that the assay can detect renin as low as 30 ng/ml after a incubation of only 3-5 min. It was estimated that with extended incubation time (2-3 h) the assay can detect renin at 0.5 ng/ml concentration level. An automated, high throughput fluorometric renin assay has been developed for a 96-well microtiter-plate fluorescence reader, which is useful for studies of enzyme inhibitors and enzyme stability.