Tuning the Magnetic Quantum Criticality of Artificial Kondo Superlattices CeRhIn_{5}/YbRhIn_{5}.

The effects of reduced dimensions and the interfaces on antiferromagnetic quantum criticality are studied in epitaxial Kondo superlattices, with alternating n layers of heavy-fermion antiferromagnet CeRhIn_{5} and seven layers of normal metal YbRhIn_{5}. As n is reduced, the Kondo coherence temperature is suppressed due to the reduction of effective Kondo screening. The Néel temperature is gradually suppressed as n decreases and the quasiparticle mass is strongly enhanced, implying dimensional control toward a quantum critical point. Magnetotransport measurements reveal that a quantum critical point is reached for the n=3 superlattice by applying small magnetic fields. Remarkably, the anisotropy of the quantum critical field is opposite to the expectations from the magnetic susceptibility in bulk CeRhIn_{5}, suggesting that the Rashba spin-orbit interaction arising from the inversion symmetry breaking at the interface plays a key role for tuning the quantum criticality in the two-dimensional Kondo lattice.

Atmospheric Humidity Influences Oviposition Rate of Tetranychus urticae (Acari: Tetranychidae) Through Morphological Responses of Host Cucumis sativus Leaves.

We investigated the effects of morphology of host cucumber, Cucumis sativus L., leaves acclimatized to different atmospheric humidity levels on oviposition by adult females of the twospotted spider mite, Tetranychus urticae Koch. Cucumber seedlings were grown at a vapor pressure deficit (VPD) of 0.4, 1.9, or 3.0 kPa at 28°C (90%, 50%, or 20% relative humidity, respectively) in growth chambers until the second true leaves had expanded. Adult females of T. urticae were released on the adaxial surfaces of leaf squares cut from first and second true leaves in each treatment group, and held in the same humidity condition. Eggs were counted 2 d after release. The lower acclimatization humidity (higher VPD) increased trichome (leaf hair) density of the host leaves and oviposition rate, but the relationship between the trichome and oviposition differed between leaf positions. The leaf mass per area (LMA) was greater in first true leaves than in second true leaves, but was not influenced by VPD. A linear regression model with oviposition rate as the dependent variable and trichome density and LMA as independent variables showed that both variables influenced the oviposition rate approximately equally. We conclude that oviposition was accelerated under low humidity (high VPD) conditions indirectly probably through an increase in the trichome density of host leaves.

Controllable Rashba spin-orbit interaction in artificially engineered superlattices involving the heavy-fermion superconductor CeCoIn5.

By using a molecular beam epitaxy technique, we fabricate a new type of superconducting superlattices with controlled atomic layer thicknesses of alternating blocks between the heavy-fermion superconductor CeCoIn5, which exhibits a strong Pauli pair-breaking effect, and nonmagnetic metal YbCoIn5. The introduction of the thickness modulation of YbCoIn5 block layers breaks the inversion symmetry centered at the superconducting block of CeCoIn5. This configuration leads to dramatic changes in the temperature and angular dependence of the upper critical field, which can be understood by considering the effect of the Rashba spin-orbit interaction arising from the inversion symmetry breaking and the associated weakening of the Pauli pair-breaking effect. Since the degree of thickness modulation is a design feature of this type of superlattices, the Rashba interaction and the nature of pair breaking are largely tunable in these modulated superlattices with strong spin-orbit coupling.

DNA barcodes for species identification in the hyperdiverse ant genus Pheidole (Formicidae: Myrmicinae).

DNA sequencing is increasingly being used to assist in species identification in order to overcome taxonomic impediment. However, few studies attempt to compare the results of these molecular studies with a more traditional species delineation approach based on morphological characters. Mitochondrial DNA Cytochrome oxidase subunit 1 (CO1) gene was sequenced, measuring 636 base pairs, from 47 ants of the genus Pheidole (Formicidae: Myrmicinae) collected in the Brazilian Atlantic Forest to test whether the morphology-based assignment of individuals into species is supported by DNA-based species delimitation. Twenty morphospecies were identified, whereas the barcoding analysis identified 19 Molecular Operational Taxonomic Units (MOTUs). Fifteen out of the 19 DNA-based clusters allocated, using sequence divergence thresholds of 2% and 3%, matched with morphospecies. Both thresholds yielded the same number of MOTUs. Only one MOTU was successfully identified to species level using the CO1 sequences of Pheidole species already in the Genbank. The average pairwise sequence divergence for all 47 sequences was 19%, ranging between 0-25%. In some cases, however, morphology and molecular based methods differed in their assignment of individuals to morphospecies or MOTUs. The occurrence of distinct mitochondrial lineages within morphological species highlights groups for further detailed genetic and morphological studies, and therefore a pluralistic approach using several methods to understand the taxonomy of difficult lineages is advocated.

Selection of microalgae suitable for culturing with digestate from methane fermentation.

The effects ofdigestate on the growth rates of Euglena gracilis, Chlorella vulgaris, and Dunaliella tertiolecta were investigated to select suitable microalgae for culturing with digestate from methane fermentation. Microalgae were cultured in an aqueous solution containing digestate at concentrations of 5%, 10%, 13%, 20%, 40%, 50%, and 100%, and Cramer-Myers (CM) solution as a control, at photosynthetic photon flux densities (PPFDs) of 75-150 micromol m(-2) s(-1) with continuous illumination at 30 degrees C. The number of cells was monitored daily, and specific growth rates (mu) were calculated as cellular multiplication rates. The maximum mu values of these species were greater in appropriate concentrations of digestate than in CM medium. The maximum mu values were 0.047 h(-1) in 10% digestate for E. gracilis, 0.065 h(-1) in 20% digestate for C. vulgaris, and 0.052 h(-1) in 50% digestate for D. tertiolecta at a PPFD of 150 micromol m(-2) s(-1). The mu of D. tertiolecta were 2.5 and 1.1 times higher than those of E. gracilis and C. vulgaris, respectively, in 50% digestate. These results demonstrated that these species could be cultured at high growth rates with diluted methane fermentation sludge and that, among these species, Dunaliella sp. was suitable for culturing at higher concentration of digestate under relatively low-level light conditions.

Actinin-4, a novel actin-bundling protein associated with cell motility and cancer invasion.

Regulation of the actin cytoskeleton may play a crucial role in cell motility and cancer invasion. We have produced a monoclonal antibody (NCC- Lu-632, IgM, k) reactive with an antigenic protein that is upregulated upon enhanced cell movement. The cDNA for the antigen molecule was found to encode a novel isoform of nonmuscle alpha-actinin. This isoform (designated actinin-4) was concentrated in the cytoplasm where cells were sharply extended and in cells migrating and located at the edge of cell clusters, but was absent from focal adhesion plaques or adherens junctions, where the classic isoform (actinin-1) was concentrated. Actinin-4 shifted steadily from the cytoplasm to the nucleus upon inhibition of phosphatidylinositol 3 kinase or actin depolymerization. The cytoplasmic localization of actinin-4 was closely associated with an infiltrative histological phenotype and correlated significantly with a poorer prognosis in 61 cases of breast cancer. These findings suggest that cytoplasmic actinin-4 regulates the actin cytoskeleton and increases cellular motility and that its inactivation by transfer to the nucleus abolishes the metastatic potential of human cancers.

Carvedilol Suppresses Apoptosis and Ion Channel Remodelling of HL-1 Cardiac Myocytes Expressing E334K cMyBPC.

BACKGROUND: Besides its antiarrhythmic action, carvedilol has an activity to suppress cardiac tissue damage. However, it is unknown whether it has any effect on cellular apoptosis and ion channel remodelling. PURPOSE: To know whether carvedilol has any effect on apoptosis and ion channel remodeling of HL-1 cells expressing E334K MyBPC, and comparing it with bisoprolol. METHOD: We examined effects of carvedilol and bisoprolol on the levels of pro- and anti-apoptotic proteins and ion channels as well as apoptosis of HL-1 cells transfected with E334K MyBPC using Western blot and flow cytometry. RESULTS: Carvedilol decreased the protein levels of p53, Bax and cytochrome c and increased that of Bcl-2 in HL-1 cells expressing E334K MyBPC. Bisoprolol failed to affect the protein levels. Both carvedilol and bisoprolol increased the protein levels of Cav1.2 but not that of Nav1.5. Carvedilol was stronger than bisoprolol at decreasing the number of annexin-V positive cells in HL-1 cells expressing E334K MyBPC. CONCLUSION: Carvedilol suppressed apoptosis of HL-1 cells expressing E334K MyBPC through modification of pro- and anti-apoptotic proteins, whose was associated with an increase of Cav 1.2 protein expression.

Serum hyaluronate in patients with acute and fulminant hepatitis.

We evaluated serum hyaluronate (HA) levels in 17 patients with acute hepatitis and 9 with fulminant hepatitis (FH). Upon admission, patients with FH showed increased levels of serum HA and these levels showed significant correlation with biochemical parameters such as human hepatocyte growth factor, hepaplastin test, and prothrombin activity. In patients with AH, the levels of serum HA decreased during convalescence. Higher serum HA levels were observed in patients with type A acute hepatitis than in patients with non-A type. In patients with FH, serum HA levels were decreased in the survivors, while they were elevated in the non-survivors. These findings suggest that serum HA levels may be a useful indicator for evaluating the prognosis of patients with acute and fulminant hepatitis. Further study is necessary to determine whether there is a causal relationship between elevated serum HA levels and the type of hepatitis virus.

Synthesis and antimicrobial activity of a new penem, sodium (5R,6S)-2-(2-fluoroethylthio)-6-[(1R)-1-hydroxyethyl]penem-3- carboxylate.

The synthesis and in vitro antimicrobial activity of a new penem antibiotic, sodium (5R,6S)-2-(2-fluoroethylthio)-6-[(1R)-1-hydroxyethyl]penem-3-ca rbo xylate (1), are reported. The MIC values of 1 are compared with those of some related 2-haloalkylthio penems prepared in this work, and also Sch 29482 and thienamycin.

Synthesis and structure-activity relationships of a novel oral carbapenem, CS-834.

We have studied an ester prodrug of a carbapenem to develop a potent orally active beta-lactam antibiotic. A variety of 1 beta-methylcarbapenem derivatives have been synthesized. We have found that some derivatives having an amide group in the C-2 side chain show potent and well balanced antibacterial activities as well as high stability against dehydropeptidase-I. Oral absorption of derivatives has been optimized by modifying the C-3 ester promoiety. Pivaloyloxymethyl (1R, 5S, 6S)-6-[(R)-1-hydroxyethyl]-l-methyl-2-[(R)-5-oxopyrrolidin-3-yl thio]- l-carbapen-2-em-3-carboxylate, CS-834, has been selected as the most promising compound for further evaluation.

Synthesis and structure-activity relationships of 1beta-methylcarbapenems with quaternary ammonium side chains.

The synthesis and antibacterial activity of 1beta-methylcarbapenems with quaternary ammonium groups at the C-2 position have been studied. Two types of new carbapenem derivatives have been synthesized. These 1beta-methylcarbapenems, one type having a (2S,4S)-2-[1,1-dimethyl-2-(1-piperazinyl)carbonyl]pyrrolidinio-4-+ ++ylthio group and the other type having a (2S,4S)-2-(4-carbamoylmethyl-4-methylhomopiperazinio-1-yl carbonyl)pyrrolidin-4-ylthio group, show potent and well balanced antibacterial activity as well as high stability against dehydropeptidase-I. The in vivo potency of these two carbapenems was compared with that of meropenem. The structure-activity relationships leading to these carbapenems are also described.

Synthesis and antibacterial activity of novel 1beta-methyl carbapenems with cycloalkylamine moiety at the C-2 position.

Novel 1beta-methyl carbapenems with a cycloalkylamine moiety as a side chain were synthesized and their structure-activity relationships were studied. These carbapenems showed potent antibacterial activities against a wide range of Gram-positive and Gram-negative bacteria, and moderate urinary recovery when administered intraperitoneally in mice.

The enzyme-linked immunosorbent assay for detecting antibodies against Dirofilaria immitis in dogs.

Antisera prepared in mice by injection of antigens from Dirofilaria immitis, Toxocara canis, Dipylidium canium and Fasciola hepatica and sera from Dirofilaria-infected and non-infected dogs were tested at different dilutions using an enzyme-linked immunosorbent assay (ELISA). For this ELISA, adult D. immitis antigen was fractionated by gel filtration methods and then absorbed with immunoadsorbent-fixed IgG fractions from mouse sera immunized with various parasites. The results indicated satisfactory discrimination between antisera to D. immitis and those to other parasites. A significant ELISA O.D. value was considered to be greater than or equal to 0.30 with a 1 : 250 dilution of the dog sera. However, the lack of significant differences between the O.D. value of microfilaraemic and amicrofilaraemic infections was observed. These facts suggest that the use of immunoadsorbent chromatography for canine dirofilariasis is especially useful for purifying antigens and eliminating cross-reactions against other parasitic infections, when immunological methods are used for serodiagnosis.

A rapid microassay for dirofilarial antibodies by using antigen-coated nitrocellulose paper.

This study describes an enzyme (horseradish peroxidase)-linked immunosorbent assay using nitrocellulose (NC) paper (Dot-ELISA) for the detection of antibodies against Dirofilaria immitis in dogs. Dirofilarial antigens prepared were directly bound on NC paper set into a microfiltration apparatus to ensure their uniformity. Of the 23 infected dogs tested, 21 were determined positive by visual observation of brown-colored spots on NC paper. The positive and negative readings were further confirmed by using a densitometer. Sera from 15 non-infected and 17 other parasite-infected dogs were all negative, i.e. no false positive readings and low cross-reactivities were found using this technique. Also, a large number of samples could be assayed simultaneously within 1.5 h. The Dot-ELISA technique reported here may be useful to veterinarians and also may be a means of field surveying human filariasis.

[Toxicological studies on puffer fishes:comparison of toxicities in the various species].

The toxicity variations of puffer fishes toxin on species, sex, organs seasons and sea area collecting subjects were observed in 615. subjects of 15 species during 1978-1981. The remarkable differences of toxicity were found by species and/or by subjects. Takifugu pardalis, Takifugu poecilonotus and Takifugu niphobles, which are habitually eaten in Japan, had a strong toxicity and some of them were strongly toxic in the muscle. It was indicated that female puffer fishes have a higher toxicity than the male. In particular, the toxicity from genital organs was significantly higher in the female puffer fishes than in male. No difference no sex was observed in the skin. Compared with the toxicities on the collecting sea areas, Inland sea of Seto and Japan sea, the mean of toxicity and the incidence rate of toxic subjects collected in Japan sea were higher than those of in Inland Sea of Seto i.e. The difference was observed by the living sea environment of puffer fishes. The wild Takifugu rubripes was obviously more toxic than the cultured. It was suggested that the variations between the wild and cultured puffer fishes should be due to the difference of the metabolism for the production and accumulation of tetrodotoxin which would be influenced by the foods and the closed environment.

[Histopathological and electron microscopic changes in mice treated with puffer fish toxin].

The histopathological examination of a male ddY mouse given an intraperitoneal injection of the crude extract containing 169 micrograms/ml of tetrodotoxin (TTX) prepared from the ovary of Takifugu porphyreus was carried out. Two crude extract solutions (0.42 and 0.21 microgram/ml) were prepared; one kills an animal in 10 min (group 1), and other kills it in 40 min (group 2) after the injection. As a result, a remarkable inflation of the gall bladder was observed macroscopically in both groups. By light microscopic observed, both groups showed the congestion in the brain, heart, liver, gall bladder, lung and kidneys, while nerve cells were characterized by the vacuolation and disappearance of Nissl's body only in group 2, probably because of the mitochondrial degeneration. Electron microscopically, a part of cristae of mitochondria and ribosome of endoplasmic reticulum disappeared or vacuolated in the nerve cells of group 2. This was also observed in a part of pre and postsynaptic mitochondria of synapse. However, little significant changes were observed in group 1 and in other tissues of group 2. These results show that a cytopathological change of mice by TTX is mainly detected in nerve tissues when a small amount of TTX is administered to the animals.

The perineuronal proteoglycan surface coat in the adult rat brain, with special reference to its reactions to Gömöri's ammoniacal silver.

The present study showed that many neurons in the adult rat brain possessed a perineuronal sulfated proteoglycan surface coat which reacted to cationic iron colloid and aldehyde fuchsin. This surface coat was stained supravitally with Ehrlich's methylene blue and doubly stained with Ehrlich's methylene blue and aldehyde fuchsin. The surface coat was also stained with Gömöri's ammoniacal silver and doubly stained with Gömöri's ammoniacal silver and cationic iron colloid. The surface coat was usually expressed together with a nerve cell surface glycoprotein net detectable with lectin Wisteria floribunda agglutinin. These findings indicate that the perineuronal proteoglycan surface coat is identical to Cajal's superficial reticulum and contains some collagenous elements. It was further demonstrated that collagenase digestion erased Gömöri's ammoniacal silver impregnation within the perineuronal proteoglycan surface coat.

Carcinogenicity of extract of airborne particles using newborn mice and comparative study of carcinogenic and mutagenic effect of the extract.

An organic extract of airborne particles collected in Tokyo and its fractions (neutral, acidic, and basic) were investigated in Ames Salmonella assays for mutagenicity and in newborn mice for carcinogenicity. Mutagenicity to TA100 and TA98 strains was detected in the whole extract, the neutral, the acidic and the basic fractions with and without metabolic activation. In the carcinogenicity test, the incidence of lung tumor was as follows: whole extract, 4/25; neutral fraction, 7/25; acidic fraction, 0/20; basic fraction, 1/11; vehicle, 2/39; and uninjected, 3/47. The neutral fraction of the extract of the airborne particles showed highly potent mutagenicity and a high incidence of lung tumors in mice.

[Leber's disease. Genetic study of a family]. / Doença de Leber. Estudo genetico de uma familia

In this paper it is done the genetic study of a large family that segregates the hereditary optical atrophy gene. The modality of the hereditary transmission is the sex-linked recessive form (Leber's form). Five generations were studied, with a total of 134 individuals. Thirteen are affected (12 men: 1 woman). The study of the heredogram allows the observation of the high occurrence of women carriers and the affected men with descendents (2 married men in the heredogram) exhibit normal offspring (22 individuals, being 16 men and 6 women). One affected woman carrier is also observed. Such observations are in accordance with the literature. This study allows one to conclude by the high importance of genetic counselling, considering that the normal women carriers, which occur in great number, segregate the gene to individuals who will manifest the atrophy.

Estimation of the functional reserve of the human liver by urinary D-glucaric acid excretion after vitamin C administration.

The excretion of D-glucaric acid in the urine (uGA) correlates with the total liver content of hepatic cytochrome P-450, the metabolism of which depends on adenosine triphosphate (ATP) being produced by intrahepatic cellular mitochondria. Five cases of compensated liver cirrhosis group with less than 0.4 mg/kg/min of the maximum removal rate of indocyanine green (ICGR max), and 5 cases with normal hepatic function (control group), were monitored for uGA before and after P-450 activation induced by administration of 1 g of vitamin-C. Before vitamin-C administration, no differences in uGA excretion were observed comparing the cirrhosis with the control group. After administration of vitamin-C, the excretion of uGA was significantly lower in the cirrhosis group. The measurement of uGA is considered to represent vitamin-C induced activation by P-450, and is a new method for evaluation of the functional reserve of the liver.