Clostridium ljungdahlii sp. nov., an acetogenic species in clostridial rRNA homology group I

Clostridium ljungdahlii sp. nov. strain ATCC 49587T (T = type strain) was isolated from chicken yard waste for its ability to produce ethanol from synthesis gas. This gram-positive, motile, sporeforming rod's metabolism was primarily acetogenic. C. ljungdahlii grew with carbon monoxide, hydrogen and carbon dioxide, ethanol, pyruvate, arabinose, xylose, fructose, or glucose. Methanol, ferulic acid, lactate, galactose, and mannose did not support growth. The G+C content was 22 to 23 mol%. C. ljungdahlii is the first acetogen in clostridial 23S rRNA homology group I.

Evaluation of a fungal antagonist, Phaeotheca dimorphospora, for biological control of tree diseases

Phaeotheca dimorphospora, which was first isolated from elm wood and found to be antagonistic in vitro against the Dutch elm disease pathogen Ophiostoma ulmi, was tested for antifungal activity in vitro against other tree pathogens by a variation of the agar layer technique. Phaeotheca dimorphospora produced antifungal compounds that were strongly inhibitory against a wide range of tree pathogens in addition to O. ulmi, such as Gremmeniella spp., Armillaria spp., Septoria musiva, Verticillium albo-atrum, Cylindrocladium floridanum, Phytophthora sp., Nectria galligena, and Heterobasidion annosum. Under light and interference microscopy, four types of morphological changes were observed in the pathogens tested: swelling of hyphae, production of resting spores such as chlamydospores and of sclerotia, extrusion of cytoplasm from hyphal tips, and bursting and destruction of mycelium. Chloroform-soluble antagonistic compounds were extracted that showed both fungicidal and fungistatic effects on the test organisms. Key words: Phaeotheca dimorphospora, biological control, fungal antagonist, hyphal interactions, antifungal metabolites, tree diseases.

Synthesis of [18F]fluoroalanine and [18F]fluorotamoxifen for imaging breast tumors

To develop ligands for imaging breast tumors, [18F]fluoro analogue of tamoxifen and [18F]fluoroalanine were radiosynthesized. In vivo biodistribution studies were performed in mammary tumor-bearing rats. In studies on the biodistribution of an [18F]fluoro analogue of tamoxifen, tumor uptake decreased when rats were pretreated with diethylstilbestrol (DES), suggesting that tracer uptake in tumors was receptor-mediated. An estrogen receptor assay indicated that tumors have a receptor density of 7.5 fmol/mg protein. Studies of the distribution of [18F]fluoroalanine in tissue showed that the tumor-to-tissue ratio increases as a function of time. Positron emission tomography (PET) images of tumor-bearing rats demonstrated that tumors can be visualized 1 h after rats are injected with an [18F]fluoro analogue of tamoxifen. PET imaging of pigs after injection of 10 mCi of [18F]fluoro analogue of tamoxifen showed uterine uptake that could be blocked by DES (50 mg). The findings suggest that both radiotracers are useful for imaging breast tumors.

Hepatocellular carcinoma with or without cirrhosis: a comparison of CT and angiographic presentations in the United States and Japan

We compared the computed tomographic (CT) and angiographic presentations of hepatocellular carcinoma (HCC) with or without cirrhosis in the United States and Japan. Tumors in the United States were advanced and less frequently associated with liver cirrhosis (association of cirrhosis: United States 56.2%, Japan 91.0%. In patients with cirrhosis, the size of the tumor tended to be smaller, and nodular tumors (single or multiple) were frequent. In early stage of HCCs with cirrhosis, tumors were hypovascular without a capsule. In advanced stage, tumors were hypervascular and a capsule was frequently observed around the tumor both with CT and angiography. HCCs without cirrhosis were seen in younger patients. These tumors were large at the time of diagnosis. A massive or diffuse mass without a capsule was frequently seen. Most tumors were hypodense on precontrast CT and hypervascular on angiography. Lymph node enlargement was significantly frequent. The radiological characteristics of HCC in both countries were significantly different depending upon associated cirrhosis, as well as the time of the diagnosis.

An examination of the effects of double-strand breaks on extrachromosomal recombination in mammalian cells

We studied the effects of double-strand breaks on intramolecular extrachromosomal homologous recombination in mammalian cells. Pairs of defective herpes thymidine kinase (tk) sequences were introduced into mouse Ltk- cells on a DNA molecule that also contained a neo gene under control of the SV40 early promoter/enhancer. With the majority of the constructs used, gene conversions or double crossovers, but not single crossovers, were recoverable. DNA was linearized with various restriction enzymes prior to transfection. Recombination events producing a functional tk gene were monitored by selecting for tk-positive colonies. For double-strand breaks placed outside of the region of homology, maximal recombination frequencies were measured when a break placed the two tk sequences downstream from the SV40 early promoter/enhancer. We observed no relationship between recombination frequency and either the distance between a break and the tk sequences or the distance between the tk sequences. The quantitative effects of the breaks appeared to depend on the degree of homology between the tk sequences. We also observed that inverted repeats recombined as efficiently as direct repeats. The data indicated that the breaks influenced recombination indirectly, perhaps by affecting the binding of a factor(s) to the SV40 promoter region which in turn stimulated or inhibited recombination of the tk sequences. Taken together, we believe that our results provide strong evidence for the existence of a pathway for extrachromosomal homologous recombination in mammalian cells that is distinct from single-strand annealing. We discuss the possibility that intrachromosomal and extrachromosomal recombination have mechanisms in common.

Intra-hepatic-arterial infusion of misonidazole--an experimental study of regional radiosensitisation by intraarterial embolisation

The purpose of this study was to generate a selective radiosensitising effect by the intra-hepatic-arterial infusion of misonidazole (MISO). MISO (10 mg) was infused after transcatheter hepatic-arterial embolisation into the livers of rabbits bearing VX2 liver cancer. This procedure was followed by 15 Gy electron irradiation. Evaluation of tumour volume and histological examination was carried out on the 7th day after treatment. The greatest tumour response was obtained in the group which received MISO followed by radiation and was characterised by extensive fibrosis around the tumour and nearly complete tumour necrosis. Liver cell regeneration was also noted in adjacent liver tissue. The advantages of regional infusion of MISO following hepatic-arterial embolisation are: (1) Selectivity increased radiosensitivity of liver cancer alongside very low drug concentration in the plasma. (2) Reduced or absent deleterious side effects of MISO with higher tumour/normal tissue ratios of drug concentration. (3) Reduced cost due to the lower dosage of MISO required for regional infusion.

Effect of endothelin-1 on the uterine vasculature of the pregnant and estrogen-treated nonpregnant sheep

OBJECTIVE

This study was designed to evaluate the uterine vascular responses to endothelin-1 in pregnant and estrogen-treated nonpregnant sheep.

STUDY DESIGN

Seven pregnant and five nonpregnant oophorectomized ewes received local uterine artery infusions of endothelin-1, norepinephrine, and phenylephrine. Arterial blood pressure, heart rate, and uterine blood flow were recorded.

RESULTS

Endothelin-1 (0.01 to 3.0 micrograms/min), norepinephrine (0.1 to 3 micrograms/min), and phenylephrine (0.1 to 10 micrograms) produced significant dose-related decreases in uterine blood flow and increases in uterine vascular resistance. On a nanomoles infused per minute basis, endothelin-1 was much more potent than norepinephrine and phenylephrine as a uterine artery vasoconstrictor in both pregnant and nonpregnant sheep. The uterine vascular responses to norepinephrine and phenylephrine were similar in pregnant and nonpregnant ewes, whereas response to endothelin-1 was blunted in pregnancy.

CONCLUSION

Endothelin-1 is an extremely potent uterine vasoconstrictor in both pregnant and nonpregnant ewes, but the uterine vascular responsiveness to endothelin-1 is decreased in pregnancy.

[Studies of cockroachcidal toxin]

A cockroachcidal bacterial isolate CW-W-90-3 was selected by egg yolk agar plate. The isolate produced phospholipase C (PLC) which was pathogenic to the nymph of cockroach. The conditions for production of high level PLC indicated that using LB medium supplement Tween-80 or minimal medium could effectively increase the activity of PLC. The optical phase for production of PLC was in the period of 12-18 hours and below pH8.0. The activity of PLC was reduced along with the culture time until 48 hours. The PLC was resistant to heat. The partially purified PLC from the culture supernatant was assayed by using cockroach nymphes and produced 71.74% mortality.

[Expression of gene products of insulin-like-growth-factor II, insulin-like-growth-factor II receptor and colony-stimulating-factor-I receptor in human primary hepatocellular carcinoma and non-cancerous liver tissues]

Western blot technique was used to detect the expression of gene products of IGF-II and IGF-II receptor as well as CSF-1 receptor in hepatocellular carcinoma and its adjacent nontumours liver tissue. A fetal expression of IGF-II was noted in 33 KD. IGF-II receptor was expressed in 260 KD and 230 KD with mature and immature forms, and CSF-1 receptor in 180 KD, 139KD and 122KD with different forms. The close relationship between the synthesized regulation and overexpression of three gene protein products and hepatocarcinogenesis was discussed.

[The patterns of the health care seeking behavior and related factors in the schizophrenic patients]

Three hundreds schizophrenic out-patients, from 6 different socioculture background psychiatric facilities in Hunan were investigated by structured interview with definite schedule. The results show that after the recognition of the problem by decision maker, 45% subjects were delayed at least one month for help-seeking, 61.3% subjects first visited the non-psychiatric agencies, and 74.3% subjects has counselled with non-psychiatric doctors or healers at least one time, especially to the healer providing superstitious or religious therapy. The help-seeking styles mainly attributes to the lower socioeconomic status of the family, inconvenient referral to the psychiatric facilities, especially if the decision maker is a female, rural resided under-educated person knowing nothing of modern psychiatry. Based on these findings, the authors urge to improve scientific psychiatric care knowledge in population, develop the resource of mental health service to facilitate the radical change of help seeking behavior of the population.

Effect of calcitonin gene-related peptide on the uterine vasculature of the nonpregnant ewe

OBJECTIVES

The current study was designed to evaluate the uterine vascular effects of calcitonin gene-related peptide on the uterine vasculature of nonpregnant sheep and compare them with the effects of prostacyclin.

STUDY DESIGN

Five nonpregnant oophorectomized ewes were instrumented with uterine and pulmonary artery flow probes and catheters. Dose-response curves were constructed according to increasing doses of calcitonin gene-related peptide (0.01, 0.03, 0.1, 0.3, 1, and 3, micrograms/min) and prostacyclin (0.03, 0.1, 0.3, 1, 3, and 10 micrograms/min) via 10-minute uterine artery infusions.

RESULTS

Both calcitonin gene-related peptide and prostacyclin produced a significant increase in uterine blood flow and a decrease in uterine vascular resistance. Calcitonin gene-related peptide was found to be approximately 17 times more potent than prostacyclin as a vasodilator. Local uterine artery infusions of calcitonin gene-related peptide led to significant increases in heart rate but did not alter blood pressure, cardiac output, or total peripheral resistance at the doses tested. In contrast, at doses of prostacyclin that produced similar uterine vasodilatation, prostacyclin led to significant decreases in systemic arterial blood pressure and total peripheral resistance and increases in heart rate and cardiac output.

CONCLUSION

These data strongly suggest that calcitonin gene-related peptide, an endogenously occurring vasoactive peptide, could play an important role in regulating uterine and systemic hemodynamics.

Reactivation of insulin-like growth factor II during hepatocarcinogenesis in transgenic mice suggests a role in malignant growth

We have studied the expression of insulin-like growth factor II (IGF-II) during hepatocarcinogenesis in four independent transgenic mouse lines. In all four lines liver-directed transgene expression induces a stepwise and relatively synchronized tumorigenesis. IGF-II reexpression occurs in all four lines irrespective of the mechanism of tumor induction. Reexpression is chronologically associated with late progression steps toward hepatocellular carcinoma and correlated with the respective tumor progression rate in each line. IGF-II activation is focal and topographically associated with high replicative activity. IGF-II mRNAs in hepatocellular carcinomas show similarities to the expression pattern in fetal liver, and a M(r) 15,000 IGF-II polypeptide accumulates intracellularly in distinct cytoplasmic preferentially perinuclear compartments. These data indicate that IGF-II reexpression is a marker for progression to hepatocellular carcinoma and may contribute to hepatocarcinogenesis via an autocrine mechanism.

Malignant transformation of human fibroblast cell strain MSU-1.1 by (+-)-7 beta,8 alpha-dihydroxy-9 alpha,10 alpha-epoxy-7,8,9,10-tetrahydrobenzo [a]pyrene

Treatment of MSU-1.1 cells, a near-diploid, karyotypically stable, infinite life-span human fibroblast strain, with (+-)-7 beta,8 alpha-dihydroxy-9 alpha,10 alpha-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene induced focus formation. Eight independent foci were isolated and the cell strains developed from them were examined for characteristics of malignant cells. Each grew to a higher density in medium containing 1% serum than did the MSU-1.1 cells. Three of the eight grew rapidly in serum-free medium without added growth factors, formed colonies in agarose with diameters of greater than or equal to 120 microns at a frequency of 5-19%, exhibited loss of genetic material, and, when injected into athymic mice, formed sarcomas that reached 6 mm in diameter within 2-3 wk. One produced high-grade sarcomas (progressively growing, invasive tumors exhibiting high mitotic activity); the other two produced low-grade sarcomas (tumors with a lower degree of mitotic activity) that developed focal areas of high-grade malignant cells if left in the animals for greater than 4 wk. A fourth cell strain formed high-grade sarcomas only after 2.5-3 mo, but the tumor-derived cells analyzed showed the same growth properties as the three malignant cell strains described above, exhibited loss of genetic material, and, when reinjected into athymic mice, produced high-grade sarcomas with a short latency period.

Immunoglobulin prophylaxis against HTLV-I in a rabbit model

We have investigated the protective effect of human T-cell leukemia virus I (HTLV-I) immune globulin (HTLVIG) against HTLV-I in rabbits. HTLVIG containing 77 mg/ml of IgG was prepared from pooled plasma from seropositive healthy persons. In the first experiment, four groups (A, B, C, and D) of three rabbits were transfused with 5 ml blood from an HTLV-I-infected rabbit. Groups A, B, and C were infused 24 h later with 10, 5, and 2 ml HTLVIG, respectively, while group D was infused with 10 ml HTLVIG 48 h later. Seroconversion for HTLV-I occurred in none of group A, one of group B, and all of groups C and D after 2-5 weeks. In the second experiment, four litters (E, F, G, and H) born to another virus-infected rabbit and consisting of 7, 5, 7, and 7 newborns, respectively, were used. Litters E and H were allowed to grow normally as controls, while litters F and G were given intraperitoneal inoculation of 3 ml/kg of HTLVIG weekly four times until weaning. Although three of litters E and H each seroconverted after 5-8 weeks, none of litters F, and one of litter G became antibody-positive after 10 weeks. Presence or absence of HTLV-I infection in all these animals was confirmed by transfusion assay or gene amplification. These results indicate that passive immunization protects rabbits against blood- and milk-borne transmission of HTLV-I.

[Analysis of essential oil from Libanotis laticalycina Shan et Sheh. by GC-MS]

60 chemical components of the essential oil from Libanotis laticalycina were identified. The contents of these components were determined by GC.

Selective amplification of periportal transitional cells precedes formation of hepatocellular carcinoma in SV40 large tag transgenic mice

In a major urinary protein (MUP)-promoter/simian virus 40 (SV40)Tag transgenic mouse line (MT-D2) the liver-directed, androgen-regulated transgene expression leads to synchronized pathology resulting in a stepwise progression to multiple hepatocellular carcinomas. SV40Tag-activated replication gives rise to two different preneoplastic alterations in hepatocytes, which are characterized in detail: 1) dysplasia and finally cell death in the original hepatocyte population and 2) amplification of periportal transitional hepatocytes leading to multifocal hyperplasia and hepatocellular carcinoma. Multifocal hyperplasia, most probably the equivalent of SV40Tag-immortalization, grows confluent and leads to hepatomegaly. SV40Tag-independent, secondary events are necessary for the tumor development from confluent hyperplasia. This allows further investigation of the steps involved in malignant transformation and progression during hepatocarcinogenesis in vivo.

The structure of the gene for ribosomal protein L5 in the archaebacterium Sulfolobus acidocaldarius

The gene for the ribosomal protein L5 from the archaebacterium Sulfolobus acidocaldarius has been isolated and sequenced. The gene codes for a basic protein of molecular weight 29 165 Da. This protein shows substantial similarity to the equivalent protein from other archaebacteria as well as from yeast, and considerably less similarity to the equivalent eubacterial protein. These results support the concept of the archaebacteria as a monophyletic kingdom more closely related to eukaryotes than to eubacteria.

Crystal structure of a bovine neurophysin II dipeptide complex at 2.8 A determined from the single-wavelength anomalous scattering signal of an incorporated iodine atom

The crystal structure of a dipeptide complex of bovine neurophysin II has been solved at 2.8 A resolution solely by using single-wavelength anomalous scattering data from a single iodinated derivative. The asymmetric unit is an elongated tetramer of dimensions 110 x 40 x 30 A, composed of two dimers related by pseudo twofold symmetry. Each monomer consists of two homologous layers, each with four antiparallel beta-strands. The two regions are connected by a helix followed by a long loop. Monomer-monomer contacts involve antiparallel beta-sheet interactions, which form a dimer with two layers of eight beta-strands. One peptide per monomer occupies the principal hormone-binding pocket formed by part of the amino-terminal region and parts of the connecting helix and loop, with binding to protein consistent with conclusions drawn from solution studies. Dimer-dimer contacts involve the Tyr49 region adjacent to this site. A fifth dipeptide, of unknown biological significance, helps to stabilize one of the monomer-monomer interfaces and the tetramer-tetramer network in the crystal.

[A study of DEAE ion exchange chromatography for the purification of hen's yolk IgG]

A DEAE ion exchange chromatography procedure performed by using either gradient or stepwise elution was developed for the purification of chicken IgG antibodies from the egg yolk of immunized hens. Following this procedure, highly purified yolk IgG preparations were obtained as identified by Sephadex G 200 gel filtration as well as sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Moreover, this procedure guaranteed the recovery of antibodies of undiminished activity. The results demonstrate that the procedure is simple, reliable and practical for the yolk IgG purification. The establishment of such a method is beneficial to the production and application of egg yolk antibodies.

[Comparative study of two methods for the extraction of yolk IgG]

Extraction of specific IgG antibodies from egg yolks of immunized hens is a convenient and economical approach to the production of diagnostic antibody reagents. In this study, two methods for the extraction of yolk IgG were constructed and compared. That either method could extract at least 15 mg of yolk IgG preparation from 1 ml of egg yolk of hyperimmunized hens clearly indicates that both methods are reliable and efficient. Yolk IgG preparations obtained by method II were purer and possessed higher antibody activity than the yolk IgG preparations produced by method I, so method II is superior to method I. Nevertheless, the yolk IgG preparations produced by method I and method II contained 22% and 16% unrelated proteins respectively. Therefore, these two methods should primarily be used for the rough extraction of hens yolk IgG antibodies. If yolk antibody reagents with higher purity are required, the yolk IgG preparations produced by both methods should be further purified.

[Comparative studies on the component contents of shensuyin in the form of bag, pill and decoction]

The water extract, sugar and total volatile oil of Shensuyin have been determined and compared in the form of bag, pill and decoction. The volatile oil constituents have been analysed preliminarily by GC, thus providing an experimental basis for improving the preparation of the drug and controlling the quality.

[Analysis and comparison of pulp vitality after total and segmental LeFort I osteotomy]

A more systematic electrical testing of pulp vitality demonstrated that the recovery rate of pulp vitality was 89.5% after 12 months of total and segmental LeFort I osteotomy. Segmental LeFort I osteotomy only imposed an interference to the speed of pulp vitality recovery. In other words, the recovery rate of pulp vitality in segmental LeFort I osteotomy was comparable to that in total LeFort I osteotomy. Maxillary segmentation inflicted a minimum damage to its adjacent teeth if clinical manipulation was meticulous and skillful. Interdental osteotomy did not exert an apparent effect on the recovery of pulp vitality and the positive rate of pulp vitality in the teeth close to it was roughly similar with that of homonymous teeth on the opposite side or their adjacent teeth on the same side.

Changes in blood lipids during six days of overfeeding with medium or long chain triglycerides

Although medium chain triglyceride (MCT) is less calorically dense than long chain triglyceride (LCT), it produces a greater thermic effect following ingestion. We hypothesized that the previously observed high rate of thermogenesis produced by MCT overfeeding was due to hepatic de novo synthesis of long chain fatty acids (LCFA) from the excess medium chain fatty acids (MCFA). To study this, we compared the effects of overfeeding MCT- and LCT-containing diets on blood lipid profiles. Ten in-patient, nonobese males were overfed (150% of estimated energy requirements) two formula diets for 6 days each, in a randomized crossover design. Diets differed only in the composition of the fat and contained either 40% of energy as MCT or LCT (soybean oil). The major differences between diets in the resulting pattern of blood lipids were: 1) a reduction in fasting serum total cholesterol concentrations with the LCT, but not the MCT diet; and 2) a threefold increase in fasting serum triglyceride concentrations with MCT, but not LCT, diet. Moreover, 10% of the fasting triglyceride fatty acids were medium chain and 40% were 16:0 with the MCT diet. This compared to 1% and 20% for medium chain and 16:0, respectively, with the LCT diet. In addition, there were increases in 16:1, 18:0, and 18:1 in the triglycerides during MCT feeding. The changes in fatty acids in triglycerides with MCT feeding are consistent with the hypothesis that excess dietary MCT cause a significant increase in the hepatic synthesis of these fatty acids from MCFA through de novo synthesis and/or chain elongation and desaturation. These processes could account for the higher rate of postprandial thermogenesis with MCT as compared to LCT.

Mansonone accumulation in elm callus induced by elicitors of Ophiostoma ulmi, and general properties of elicitors

Fungal culture filtrates, cytoplasm, and cell walls of Ophiostoma ulmi contain molecules that elicit mansonone (phytoalexin) accumulation in elm calli. The elicitors from nonaggressive isolate Q311 cause a more rapid reaction on bioassays than those from the aggressive isolate MH75. On the callus of a susceptible elm (Ulmus americana), the elicitors from both isolates cause higher amounts of mansonone production than on the callus of a resistant elm (Ulmus pumila). These elicitors are heat stable, and their eliciting activities are partially sensitive to NaIO4, pronase E, proteinase K, and various hydrolytic enzymes. However, β-glucosidase treated elicitors have increased eliciting activities. The binding of Q311 culture filtrate elicitors to a concanavalin A – sepharose 4B column suggests that glycoproteins may be involved in elicitation. Some abiotic factors stimulate only small amounts of mansonone F accumulation in treated elm cells.

A phylogenetic analysis of the mycoplasmas: basis for their classification

Small-subunit rRNA sequences were determined for almost 50 species of mycoplasmas and their walled relatives, providing the basis for a phylogenetic systematic analysis of these organisms. Five groups of mycoplasmas per se were recognized (provisional names are given): the hominis group (which included species such as Mycoplasma hominis, Mycoplasma lipophilum, Mycoplasma pulmonis, and Mycoplasma neurolyticum), the pneumoniae group (which included species such as Mycoplasma pneumoniae and Mycoplasma muris), the spiroplasma group (which included species such as Mycoplasma mycoides, Spiroplasma citri, and Spiroplasma apis), the anaeroplasma group (which encompassed the anaeroplasmas and acholeplasmas), and a group known to contain only the isolated species Asteroleplasma anaerobium. In addition to these five mycoplasma groups, a sixth group of variously named gram-positive, walled organisms (which included lactobacilli, clostridia, and other organisms) was also included in the overall phylogenetic unit. In each of these six primary groups, subgroups were readily recognized and defined. Although the phylogenetic units identified by rRNA comparisons are difficult to recognize on the basis of mutually exclusive phenotypic characters alone, phenotypic justification can be given a posteriori for a number of them.

In vitro percutaneous absorption and stratum corneum binding of alachlor: effect of formulation dilution with water

The effect of vehicle dilution on the percutaneous absorption of alachlor, 2-chloro-2',6'-diethyl-N-(methoxymethyl)acetanilide, through excised human skin was determined using flowthrough design glass penetration cells and 14C radiotracer methodology. Three dilutions of alachlor (in the solubilizing commercial formulation) with distilled water were utilized: 1:20, 1:40, and 1:80 (v/v); corresponding to concentrations of 23.0, 11.8, and 5.98 mg alachlor per milliliter, respectively. Skin from the penetration studies and human powdered stratum corneum from the binding studies demonstrated a high capacity for alachlor. A soap and water (1:1, v/v) solution effectively decontaminated powdered stratum corneum. Using plasma as the receptor solution, penetration ranged from 0.5 to 4% of the applied dose for an 8-hr exposure period. Lag times of 1.2 to 1.8 hr were observed. Increasing dilution resulted in significant enhancement (p less than 0.01) in the rate and extent of alachlor penetration. Although the biological significance of this observation is unclear, this phenomenon might be explored in future studies because of its ramifications for human toxicity and for decontamination opportunities.

Thermogenesis in humans during overfeeding with medium-chain triglycerides

To test whether excess dietary energy as medium-chain triglycerides (MCT) affects thermogenesis differently from excess dietary energy as long chain triglycerides (LCT), ten male volunteers (ages 22 to 44) were overfed (150% of estimated energy requirement) liquid formula diets containing 40% of fat as either MCT or LCT. Each patient was studied for one week on each diet in a double-blind, crossover design. Resting metabolic rate (RMR) did not change during either week of overfeeding. The thermic response to food (TEF) was greater on day 1 following a meal (1,000 kcal) containing MCT than following an isocaloric meal containing LCT (8 +/- .8% v 5.8 +/- .8% of ingested energy; P less than .05). Moreover, the TEF observed after a 1,000 kcal meal containing MCT increased significantly to 12% (+/- 1.3%) overfeeding. The TEF of the 1,000 kcal meal containing LCT was unchanged by five days of LCT overfeeding (6.6 +/- 1.0% of ingested energy). Energy expenditure during a 20-hour continuous enteral infusion of the diet on day 7 was also significantly higher with the MCT diet than with the LCT diet (15.7 +/- 1.7% v 7.3 +/- .9% of ingested energy; P less than .05). Our results demonstrate that excess dietary energy as MCT stimulates thermogenesis to a greater degree than does excess energy as LCT. This increased energy expenditure, most likely due to lipogenesis in the liver, provides evidence that excess energy derived from MCT is stored with a lesser efficiency than is excess energy derived from dietary LCT.

Purification and N-terminal partial sequence of anti-epilepsy peptide from venom of the scorpion Buthus martensii Karsch

An anti-epilepsy peptide (AEP) was isolated and purified from venom of the scorpion Buthus martensii Karsch. The purification procedure included CM-Sephadex C-50 chromatography, gel filtration on Sephadex G-50 and DEAE-Sephadex A-50 chromatography. Its homogeneity was demonstrated by pH 4.3 polyacrylamide-disc-gel electrophoresis, focusing electrophoresis and SDS/polyacrylamide-disc-gel electrophoresis. The Mr of this peptide, calculated from measurements in SDS/15%-polyacrylamide-disc-gel and SDS/20%-polyacrylamide-disc-gel electrophoresis, is 8300. The isoelectric point is 8.52 by pH 8-9.5-range isoelectric focusing. No haemorrhagic or toxic activities were found. No toxicity was found even after the dose reached 28 mg/kg. The pharmacological tests showed that the AEP had no effect on heart rate, blood pressure or electrocardiogram, but strongly inhibited epilepsy induced by coriaria lactone and cephaloridine. The fluorescence spectrum showed that the peptide has a strong emission peak at 337 nm. Amino acid analysis suggested that the AEP is composed of 66 residues from 18 amino acids and has an Mr of 8290. The sequence of the first 50 N-terminal residues is as follows: Asp-Gly-Tyr-Ile-Arg-Gly-Ser-Asp-Asn-Cys-Lys-Val-Ser-Cys-Leu-Leu-Gly-Asn- Glu-Gly - Cys-Asn-Lys-Glu-Cys-Arg-Ala-Tyr-Gly-Ala-Ser-Tyr-Gly-Tyr-Cys-Trp-Thr-Val- Lys-Leu - Ala-Gln-Asp-Cys-Glu-Gly-Leu-Pro-Asp-Thr-.

Congenital poisoning by polychlorinated biphenyls and their contaminants in Taiwan

In 1979, a mass poisoning occurred in Taiwan from cooking oil contaminated by thermally degraded polychlorinated biphenyls. Because these chemicals persist in human tissue, children born to female patients after the outbreak were exposed in utero. In 1985, 117 children born to affected women and 108 unexposed controls were examined and evaluated. The exposed children were shorter and lighter than controls; they had abnormalities of gingiva, skin, nails, teeth, and lungs more frequently than did controls. The exposed children showed delay of developmental milestones, deficits on formal developmental testing, and abnormalities on behavioral assessment. These findings are most consistent with a generalized disorder of ectodermal tissue. This syndrome is one of very few documented to result from transplacental exposure to pollutant chemicals.

Crystals of modified bovine neurophysin II

An enzymatically modified form of bovine neurophysin II has been crystallized in three unique crystal forms. The orthorhombic form crystallizes in space group P2(1)2(1)2 with a = 15.33 nm, b = 6.92 nm, c = 3.63 nm, with four molecules in the asymmetric unit. The monoclinic form crystallizes in space group P2(1) with a = 6.22 nm, b = 9.55 nm, c = 5.45 nm and beta = 110.2 degrees, with eight molecules in the asymmetric unit. The tetragonal form crystallizes in space group P4(1)2(1)2 or P4(3)2(1)2 with a = 14.1 nm and c = 14.2 nm, with twelve molecules in the asymmetric unit. We report here the crystallization conditions, as well as the crystal data.

The resting cardiointegram: correlation with stress thallium perfusion studies

The cardiointegram is a noninvasive technique for the analysis of the electrical signals of the heart obtained by a transformation of the voltage versus time format by a series of integrations. The stress thallium perfusion study is a widely used test for the detection of coronary artery disease. In order to evaluate the correlation between the resting cardiointegram and the stress thallium 201 perfusion study, 20 patients with normal resting electrocardiograms underwent stress thallium tests and resting cardiointegrams. The cardiointegram was determined on two resting complexes of leads I, II, V4, V5, and V6 and called abnormal if five of ten complexes deviated outside a normalized template. There was concordance of the cardiointegram and the thallium study in 16 of 20 patients (80%). The sensitivity for the detection of coronary artery disease was 71%, and the specificity was 80%. The overall accuracy was 74%. Thus in patients with normal electrocardiograms, the cardiointegram is a useful noninvasive test for the detection of coronary artery disease.

The primary structure of the lactate dehydrogenase isozyme M4 from giant panda

The amino acid sequences of tryptic, chymotryptic and cyanogen bromide cleavage peptides of the lactate dehydrogenase isozyme M4 from giant panda have been determined. Based on the overlapping peptides and by a comparison with the known sequence of porcine lactate dehydrogenase isozyme M subunit, the complete primary structure of the giant panda lactate dehydrogenase isozyme M subunit has been established. The polypeptide chain of giant panda lactate dehydrogenase isozyme M subunit consists of 331 amino acid residues. There is a variance of 17 amino acid residues between the porcine and the giant panda lactate dehydrogenase isozyme M subunits. Most of the variable residues are substitutions by chemically similar amino acids and take place at residues not related to the active center of the enzyme.

Effect of oral alcohol on left ventricular ejection fraction, volumes, and segmental wall motion in normals and in patients with recent myocardial infarction

A first-pass nuclear angiogram and a multiple-gated acquisition study were obtained in 10 normal physicians and in 10 patients with a 7-to-10 day old transmural myocardial infarction. After the scan the subjects drank 2 oz. of whiskey. After 60 minutes, the multiple-gated acquisition study was repeated. In the normal group the left ventricular ejection fraction was 68% before and 72% after alcohol. The left ventricular end-diastolic volume increased from 89 to 97 ml while the left ventricular end-systolic volume decreased from 29 to 27 ml. The stroke volume rose from 61 to 70 ml/beat (p less than 0.05). The cardiac output increased from 4.0 to 5.0 l/min (p less than 0.05). In the infarction group, the left ventricular ejection fraction was 58% before and 56% after alcohol administration. The left ventricular end-diastolic volume fell from 111 to 96 ml, while the left ventricular end-systolic volume declined from 50 to 44 ml. The stroke volume fell from 61 to 52 ml/beat, while the cardiac output fell from 4.5 to 3.8 l/min. In the left ventricular infarction zones, alcohol produced in 9 of the 10 cardiac patients a decline in the left ventricular regional ejection fraction. In the normal group, alcohol produced no significant changes in the regional ejection fraction. The normal and the postinfarction patients responded differently to alcohol.

Mitochondrial origins

The 16S ribosomal RNA sequences from Agrobacterium tumefaciens and Pseudomonas testosteroni have been determined to further delimit the origin of the endosymbiont that gave rise to the mitochondrion. These two prokaryotes represent the alpha and beta subdivisions, respectively, of the so-called purple bacteria. The endosymbiont that gave rise to the mitochondrion belonged to the alpha subdivision, a group that also contains the rhizobacteria, the agrobacteria, and the rickettsias--all prokaryotes that have developed intracellular or other close relationships with eukaryotic cells.

[Effect of microwave contraception on human serum testosterone and luteinizing hormone]

Using home-made match kits and radioimmunoassay, both serum luteinizing hormone (LH) and testosterone (T) were measured in 53 healthy adult males using microwave contraception and 76 normal fertility males as control. The results showed that in contraceptive group the serum T level was significantly decreased (p 0.0001), while serum LH was apparently elevated (p 0.01) as compared whith the normal controls. Furthermore, the longer exposure duration the lower serum T declined and the higher serum LH increased (p 0.001). The present study suggests that the microwave dose used for contraception seems to cause damage in Leydig cell function in terms of T production, and then influence endocrine function of testis. The progressively increased LH level also indicates certain degree damage of the Leydig cells. However, the damage might be reversible. The results may be useful for further clinical investigation.

High-performance liquid chromatographic separations on dihydroxyboryl-agarose

This paper (which is part of a series of articles on high-performance liquid chromatographic separations on agarose columns) describes the chromatographic behaviour of catecholamines, nucleosides, aminoacylated and non-aminoacylated tRNA, and glycosylated and non-glycosylated hemoglobins on agarose matrices derivatized with m-aminophenylboronic acid. These matrices primarily bind molecules with two vicinal hydroxy groups in the cis-configuration. The possible existence of secondary electrostatic and hydrophobic interactions has been studied with the aid of diagrams showing retention time as a function of pH and buffer concentration.

Value of radionuclide angiogram for the diagnosis of Ebstein's anomaly

A radionuclide angiogram in a patient with Ebstein's anomaly showed a very dilated right atrium with a minimally enlarged right ventricle and a normal sized left ventricle. This study led to the establishment of a definitive diagnosis by means of an echocardiogram. Late close of the tricuspid valve was demonstrated. In addition prolapse of the tricuspid and mitral valves was documented. A tricuspid valve prolapse has never been reported in this condition.

Colorimetric determination of microgram quantities of polylysine by trypan blue precipitation

A simple and sensitive method for the determination of polylysine in solution is described. Polylysine is quantitatively precipitated with trypan blue. The absorbance of unbound dye in the supernatant is inversely proportional to the concentration of this polyamino acid. The precipitation is identical for all sizes of polylysine of molecular weight 13,000 or higher, and is prevented by the addition of either polyanions or serum. The measurable range of polylysine hydrobromide is between 1 and 10 micrograms/ml, which is about 10-fold lower than that by the published methyl orange precipitation method.