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2.
J Infect Chemother ; 29(2): 143-149, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36265821

RESUMEN

The present study compared trends in antimicrobial resistance patterns in pathogens isolated from skin and soft-tissue infections (SSTIs) in Japan with those of a nationwide survey conducted in 2013. Three organisms that caused most of the SSTIs were collected from 12 dermatology departments in medical centers and 12 dermatology clinics across Japan between April 2019 and August 2020. A total of 390 strains, including 267 Staphylococcus aureus, 109 coagulase-negative staphylococci (CNS), and 14 Streptococcus pyogenes strains were submitted to a central laboratory for antimicrobial susceptibility testing. Patient demographic and clinical information was collated. Methicillin-resistant S. aureus (MRSA) was detected in 25.8% (69/267) of the S. aureus strains. The prevalence of MRSA between the present study and the 2013 survey did not differ significantly. Furthermore, there were no significant differences in MIC values and susceptibility patterns of the MRSA strains to other agents, regardless of a history of hospitalization within 1 year or invasive medical procedures. Methicillin-resistant CNS (MRCNS) was detected in 48.6% (53/109) of CNS isolates, higher than the 35.4% prevalence in the 2013 survey. This difference could be attributed to the heterogeneity in the members of the MRCNS, which comprises multiple staphylococci species, between the 2013 and 2019 surveys. However, it was noted that the susceptibility profiles of the MRCNS to each antibiotic were not significantly different from those identified in the 2013 survey. Most strains of S. pyogenes were susceptible to each antibiotic, similar to the 2013 survey. Continuous monitoring of trends in pathogen and susceptibility profiles is important to advise local public health efforts regarding the appropriate treatment of SSTIs.


Asunto(s)
Dermatología , Staphylococcus aureus Resistente a Meticilina , Infecciones de los Tejidos Blandos , Infecciones Estafilocócicas , Infecciones Cutáneas Estafilocócicas , Humanos , Staphylococcus aureus , Infecciones Cutáneas Estafilocócicas/tratamiento farmacológico , Infecciones Cutáneas Estafilocócicas/epidemiología , Infecciones Cutáneas Estafilocócicas/microbiología , Japón/epidemiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Infecciones de los Tejidos Blandos/epidemiología , Infecciones de los Tejidos Blandos/microbiología , Streptococcus pyogenes , Pruebas de Sensibilidad Microbiana
3.
J Phys Condens Matter ; 33(23)2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33784658

RESUMEN

We report superconductivity in SnxNbSe2-δ, a topological nodal-line semimetal candidate with a noncentrosymmetric crystal structure. The superconducting transition temperatureTcof this compound is extremely sensitive to Sn concentrationxand Se deficiencyδ, 5.0 K for Sn0.13NbSe1.70and 8.6 K for Sn0.14NbSe1.71and Sn0.15NbSe1.69. In all samples, the temperature dependence of the upper critical fieldHc2(T) differs from the prediction of the Werthamer-Helfand-Hohenberg theory. While the zero-temperature value of the in-plane upper critical field of SnxNbSe2-δwith the higherTcis lower than the BCS Pauli paramagnetic limitHP, that of the lowerTcsample exceedsHPby a factor of ∼2. Our observations suggest that a possible odd-parity contribution dominates the superconducting gap function of SnxNbSe2-δ, and it can be fine-tuned by the Sn concentration and Se deficiency.

4.
J Phys Condens Matter ; 33(17)2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33508812

RESUMEN

In the search of topological superconductors, nailing down the Fermiology of the normal state is as crucial a prerequisite as unraveling the superconducting pairing symmetry. In particular, the number of time-reversal-invariant momenta (TRIM) in the Brillouin zone enclosed by Fermi surfaces is closely linked to the topological class of time-reversal-invariant systems, and can experimentally be investigated. We report here a detailed study of de Haas van Alphen quantum oscillations in single crystals of the topological semimetal CaSn3with torque magnetometry in high magnetic fields up to 35 T. In conjunction with density functional theory based calculations, the observed quantum oscillations frequencies indicate that the Fermi surfaces of CaSn3enclose an odd number of TRIM, satisfying one of the proposed criteria to realize topological superconductivity. Nonzero Berry phases extracted from the magnetic oscillations also support the nontrivial topological nature of CaSn3.

6.
PLoS One ; 14(5): e0215614, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31063502

RESUMEN

The Intergovernmental Panel on Climate Change recommends keeping the increase in temperature to less than a two-degree increase by the end of the century, but the direct impact of global warming on ecosystems including microbes has not been investigated. Here we performed thermal adaptation of two species and three strains of mesophilic microbes for improvement of the survival upper limit of temperature, and the improvement was evaluated by a newly developed method. To understand the limitation and variation of thermal adaptation, experiments with mutators and by multiple cultures were performed. The results of experiments including genome sequencing and analysis of the characteristics of mutants suggest that these microbes bear a genomic potential to endure a 2-3°C rise in temperature but possess a limited variation of strategies for thermal adaptation.


Asunto(s)
Aclimatación , Escherichia coli/crecimiento & desarrollo , Zymomonas/crecimiento & desarrollo , Ecosistema , Escherichia coli/genética , Genoma Bacteriano , Calentamiento Global , Secuenciación de Nucleótidos de Alto Rendimiento , Secuenciación Completa del Genoma , Zymomonas/genética
7.
Sci Adv ; 4(4): eaao4513, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29740606

RESUMEN

In all known fermionic superfluids, Cooper pairs are composed of spin-1/2 quasi-particles that pair to form either spin-singlet or spin-triplet bound states. The "spin" of a Bloch electron, however, is fixed by the symmetries of the crystal and the atomic orbitals from which it is derived and, in some cases, can behave as if it were a spin-3/2 particle. The superconducting state of such a system allows pairing beyond spin-triplet, with higher spin quasi-particles combining to form quintet or septet pairs. We report evidence of unconventional superconductivity emerging from a spin-3/2 quasi-particle electronic structure in the half-Heusler semimetal YPtBi, a low-carrier density noncentrosymmetric cubic material with a high symmetry that preserves the p-like j = 3/2 manifold in the Bi-based Γ8 band in the presence of strong spin-orbit coupling. With a striking linear temperature dependence of the London penetration depth, the existence of line nodes in the superconducting order parameter Δ is directly explained by a mixed-parity Cooper pairing model with high total angular momentum, consistent with a high-spin fermionic superfluid state. We propose a k ⋅ p model of the j = 3/2 fermions to explain how a dominant J = 3 septet pairing state is the simplest solution that naturally produces nodes in the mixed even-odd parity gap. Together with the underlying topologically nontrivial band structure, the unconventional pairing in this system represents a truly novel form of superfluidity that has strong potential for leading the development of a new series of topological superconductors.

8.
Sci Adv ; 1(5): e1500242, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26601201

RESUMEN

We report superconductivity and magnetism in a new family of topological semimetals, the ternary half-Heusler compound RPdBi (R: rare earth). In this series, tuning of the rare earth f-electron component allows for simultaneous control of both lattice density via lanthanide contraction and the strength of magnetic interaction via de Gennes scaling, allowing for a unique tuning of the normal-state band inversion strength, superconducting pairing, and magnetically ordered ground states. Antiferromagnetism with ordering vector (½,½,½) occurs below a Néel temperature that scales with de Gennes factor dG, whereas a superconducting transition is simultaneously supressed with increasing dG. With superconductivity appearing in a system with noncentrosymmetric crystallographic symmetry, the possibility of spin-triplet Cooper pairing with nontrivial topology analogous to that predicted for the normal-state electronic structure provides a unique and rich opportunity to realize both predicted and new exotic excitations in topological materials.

9.
J Vet Med Sci ; 73(5): 665-71, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21224530

RESUMEN

Seven miniature pigs were injected intravenously with deoxynivalenol (DON) at 1 mg/kg body weight; afterward, the number of leukocytes in peripheral blood, the luminol-dependent chemiluminescence of neutrophils, the serum or plasma concentration of cytokines and acute-phase proteins were evaluated to determine the effects of acute exposure to DON on inflammatory responses. White blood cell counts were transiently increased at 3, 6, and 12 hr post-injection (PI) due to the increased number of neutrophils. The luminol-dependent chemiluminescence value of neutrophils was significantly elevated at 24 hr PI, indicating the activation of the bactericidal function of neutrophils. Significant increases of interleukin (IL)-8 and tumor necrosis factor-α at 3 hr PI and IL-6 at 6 hr PI were detected in the serum. The concentration of haptoglobin and serum amyloid A was significantly increased at 24 hr PI. These results suggest that acute exposure to DON induced a temporary recruitment of neutrophils in the peripheral blood by IL-8 and subsequent activation of the bactericidal function, and a transient increase of proinflammatory cytokines and acute-phase proteins, indicating the immunomodulatory effects of DON in pigs.


Asunto(s)
Inflamación/veterinaria , Enfermedades de los Porcinos/inducido químicamente , Tricotecenos/toxicidad , Proteínas de Fase Aguda/metabolismo , Animales , Citocinas/genética , Citocinas/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Inflamación/inducido químicamente , Luminiscencia , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Porcinos , Porcinos Enanos , Factores de Tiempo
10.
J Vet Sci ; 11(2): 107-13, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20458150

RESUMEN

Six 1-month-old piglets were intravenously injected with deoxynivalenol (DON) at the concentration of 1 mg/kg body weight, with three pigs each necropsied at 6 and 24 h post-injection (PI) for investigation of hepatotoxicity and immunotoxicity with special attention to apoptotic changes and cytokine mRNA expression. Histopathological examination of the DON-injected pigs revealed systemic apoptosis of lymphocytes in lymphoid tissues and hepatocytes. Apoptosis of lymphocytes and hepatocytes was confirmed by the TdT-mediated dUTP-biotin nick end-labeling (TUNEL) method and immunohistochemical staining against singlestranded DNA and cleaved caspase-3. The number of TUNELpositive cells in the thymus and Peyer's patches of the ileum was increased at 24 h PI compared to 6 h PI, but the peak was at 6 h PI in the liver. The mRNA expression of interleukin (IL)-1beta, IL-6, IL-18, and tumor necrosis factor (TNF)-alpha in the spleen, thymus and mesenteric lymph nodes were determined by semi-quantitative RT-PCR, and elevated expression of IL-1beta mRNA at 6 h PI and a decrease of IL-18 mRNA at 24 h PI were observed in the spleen. IL-1beta and IL-6 mRNA expressions increased significantly at 6 h PI in the thymus, but TNF-alpha decreased at 6 h PI in the mesenteric lymph nodes. These results show the apoptosis of hepatocytes suggesting the hepatotoxic potential of DON, in addition to an immunotoxic effect on the modulation of proinflammatory cytokine genes in lymphoid organs with extensive apoptosis of lymphocytes induced by acute exposure to DON in pigs.


Asunto(s)
Apoptosis/efectos de los fármacos , Citocinas/biosíntesis , Hígado/efectos de los fármacos , Tejido Linfoide/efectos de los fármacos , ARN Mensajero/biosíntesis , Porcinos/inmunología , Tricotecenos/toxicidad , Animales , Apoptosis/inmunología , Citocinas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Histocitoquímica/veterinaria , Etiquetado Corte-Fin in Situ/veterinaria , Hígado/inmunología , Tejido Linfoide/inmunología , ARN Mensajero/genética , ARN Mensajero/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Organismos Libres de Patógenos Específicos
11.
Sci Technol Adv Mater ; 9(4): 044206, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27878023

RESUMEN

R2Fe3Si5 (R= Sc, Y, Lu) contains nonmagnetic iron and has a relatively high superconducting transition temperature Tc among iron-containing superconductors. An anomalous temperature dependence of specific heat C(T) has been reported for polycrystalline samples down to 1 K. We have grown R2Fe3Si5 single crystals, confirmed the anomalous C(T) dependence, and found a second drop in specific heat below 1 K. In Lu2Fe3Si5, we can reproduce C(T) below Tc, assuming two distinct energy gaps 2Δ 1/kBTc = 4.4 and 2Δ 2/kBTc = 1.1, with nearly equal weights, indicating that Lu2Fe3Si5 is a two-gap superconductor similar to MgB2. Hall coefficient measurements and band structure calculation also support the multiband contributions to the normal-state properties. The specific heat in the Sc2Fe3Si5 single crystals also shows the two-gap feature. R5Ir4Si10 (R = Sc, rare earth) is also a superconductor where competition between superconductivity and the charge-density wave is known for rare earths but not for Sc. We have performed detailed specific heat measurements on Sc5Ir4Si10 single crystals and found that C(T) deviates slightly from the behavior expected for weak-coupling superconductors. C(T) for these superconductors can also be reproduced well by assuming two superconducting gaps.

12.
J Vet Med Sci ; 68(10): 1113-5, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17085894

RESUMEN

Genetically modified corn Bt11 is insect-resistant and expresses Cry1Ab toxin, an insecticidal protein, in kernels. Although Bt11 corn is considered safe based on animal performance, there are no reports available on the clinico-biochemical effects of feeding it to cattle. In this study, we evaluated the effects of feeding Bt11 to calves, using blood and ruminal clinico-biochemical parameters. Our three-month-long feeding experiment demonstrated that calves (n=6), fed with a ration containing 43.3% of Bt11 corn kernels as dry matter, did not develop any discernible clinical, hematological, biochemical, or ruminal abnormalities as compared with control calves (n=6) fed non-Bt11 corn. The results suggest that the transgenic Bt11 has no negative clinico-biochemical effects on calves.


Asunto(s)
Bovinos/metabolismo , Alimentos Modificados Genéticamente , Plantas Modificadas Genéticamente/metabolismo , Zea mays/metabolismo , Alanina Transaminasa/sangre , Alimentación Animal , Animales , Aspartato Aminotransferasas/sangre , Análisis Químico de la Sangre/veterinaria , Peso Corporal , Bovinos/sangre , Recuento de Eritrocitos/veterinaria , Ácidos Grasos Volátiles/análisis , Hematócrito/veterinaria , Hemoglobinas/análisis , Recuento de Leucocitos/veterinaria , Plantas Modificadas Genéticamente/genética , Rumen/metabolismo , Zea mays/genética , gamma-Glutamiltransferasa/sangre
13.
J Vet Med Sci ; 67(7): 735-8, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16082126

RESUMEN

Reproductive failure associated with porcine circovirus type 2 (PCV2) was observed in a farm, and a weak-born 8-day-old piglet was examined pathologically. Focal to locally extensive lesions, including infiltration of macrophages and lymphocytes, fibrosis and degeneration of the myocardium were observed in the heart. PCV2 antigens and nucleic acids were detected in degenerated cardiomyocytes and macrophages infiltrating the heart by immunohistochemical staining and in situ hybridization. Depletion of lymphocytes with occasional infiltration of multinucleated giant cells was seen in the lymphoid organs and PCV2 antigens were demonstrated in histiocytic cells. Crystalline arrays of viral particles were observed in infiltrated macrophages in the heart and, rarely, in cardiomyocytes by electron microscopy. Although myocarditis is a common finding in aborted or stillborn piglets in reproductive failure due to PCV2, it was also observed in the 8-day-old piglet with PCV2 association.


Asunto(s)
Infecciones por Circoviridae/veterinaria , Circovirus/genética , Miocarditis/veterinaria , Enfermedades de los Porcinos/patología , Enfermedades de los Porcinos/virología , Animales , Antígenos Virales/genética , Infecciones por Circoviridae/patología , Cartilla de ADN , Inmunohistoquímica/veterinaria , Hibridación in Situ/veterinaria , Microscopía Electrónica/veterinaria , Miocarditis/patología , Miocarditis/virología , Miocardio/ultraestructura , Reacción en Cadena de la Polimerasa , Sus scrofa
14.
Toxicology ; 204(2-3): 241-9, 2004 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-15388250

RESUMEN

Deoxynivalenol (DON) is one of the major mycotoxic contaminants of grains, which causes reduced weight gain in pigs. The cytotoxicity of DON to porcine hepatocytes was examined in this study. DON was added at the final concentration of 100, 10, 1, 0.1 or 0.01 microg/ml to the medium of primary cultured hepatocytes. Cell death of the hepatocytes was observed in DON 100 and 10 microg/ml groups from 6 h after the addition, and in DON 100, 10, 1 and 0.1 microg/ml groups at 24 h in a dose-dependent manner. The dead hepatocytes showed chromatin condensation and fragmentation of the nuclei, which are considered characteristic morphological changes of apoptosis. The nuclei of the dead hepatocytes were stained positively by the TUNEL method. Lactate dehydrogenase (LDH) release, which is considered leakage from apoptotic hepatocytes into the medium, was apparent at 24 h after DON addition. Increased caspase-3 activity was seen in DON 100, 10 and 1 microg/ml groups. Albumin secretion into the medium was significantly reduced in DON 100, 10 and 1microg/ml groups, moderately in the 0.1 microg/ml group, and slightly in the 0.01 microg/ml group. These results indicate that DON induced apoptosis through the caspase-3 activation pathway and caused functional disorder in porcine hepatocytes.


Asunto(s)
Apoptosis/efectos de los fármacos , Hepatocitos/metabolismo , Hepatocitos/patología , Albúmina Sérica/metabolismo , Tricotecenos/farmacología , Animales , Apoptosis/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Hepatocitos/efectos de los fármacos , Porcinos
15.
J Food Prot ; 67(2): 365-70, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14968971

RESUMEN

The presence of maize intrinsic and recombinant cry1Ab genes in the gastrointestinal (GI) contents, peripheral blood mononuclear cells (PBMC), and visceral organs of calves fed genetically modified Bt11 maize was examined by PCR in a subchronic 90-day performance study. Samples were collected from six Japanese Black/Holstein calves fed Bt11 maize and from six calves fed non-Bt maize. Fragments of maize zein (Ze1), invertase, chloroplast, and cry1Ab were detected inconsistently in the rumen fluid and rectal contents 5 and 18 h after feeding. The chloroplast DNA fragments of ribulose-1,5-bisphosphate carboxylase/oxygenase and tRNA were detected inconsistently in the PBMC, the visceral organs, and the longissimus muscle, while the cry1Ab gene was never detected in PBMC or in the visceral organs. These results suggest that feed-derived maize DNA was mostly degraded in the GI tract but that fragmented DNA was detectable in the GI contents as a possible source of transfer to calf tissues. These results also suggest that the recombinant cry1Ab genes were not transferred to the PBMC and tissues of calves fed Bt11 maize.


Asunto(s)
Alimentación Animal , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas , Bovinos/metabolismo , ADN Recombinante/análisis , Endotoxinas/metabolismo , Plantas Modificadas Genéticamente , Zea mays/genética , Animales , Toxinas de Bacillus thuringiensis , ADN de Plantas/análisis , Contenido Digestivo/química , Proteínas Hemolisinas , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/veterinaria , Distribución Aleatoria
16.
J Vet Med Sci ; 64(10): 937-9, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12419872

RESUMEN

A holstein calf with congenital chondrodysplastic dwarfism was histopathologically examined. The head of the calf was relatively flat giving a dog-like appearance with its short nose and sloping forehead. Limb bones were dumbbell-like with short diaphysis and hypertrophied metaphyses. Bone marrow was pale, whitish and fatty. In the metaphyseal plates most of chondrocytes were pyknotic with swollen and ghost-like cytoplasm, and were irregularly arranged. Column of calcified cartilage were poorly formed losing comb-like structure. Bone marrow was ischemic with poor hematopoiesis and was moderately replaced by adipose tissue. In articular cartilage, most of chondrocytes were degenerated with ghost-like cytoplasm. Many cartilage canals and occasional bone marrow-like structure were formed. The characteristics lesions of the calf were chondrodysplasia and dyshematopoiesis.


Asunto(s)
Enfermedades de los Bovinos/congénito , Bovinos/anomalías , Enanismo/congénito , Enanismo/veterinaria , Osteocondrodisplasias/congénito , Osteocondrodisplasias/veterinaria , Animales , Médula Ósea/anomalías , Médula Ósea/patología , Huesos/anomalías , Huesos/patología , Enfermedades de los Bovinos/patología , Condrocitos/patología , Femenino , Deformidades Congénitas de las Extremidades/patología , Deformidades Congénitas de las Extremidades/veterinaria , Osteocondrodisplasias/patología
17.
J Interferon Cytokine Res ; 22(8): 883-9, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12396728

RESUMEN

In this study, we investigated the expression of interleukin-18 (IL-18) in porcine airway and intestinal epithelium. We found constitutive protein expression of precursor IL-18 in primary culture of porcine airway epithelium. Immunohistochemical staining revealed that porcine IL-18 was localized in the porcine airway epithelium and that it was significantly upregulated with experimental endotoxemia induced by Escherichia coli lipopolysaccharide (LPS) inoculation. We also confirmed by immunohistochemical staining that IL-18 was expressed in porcine intestinal epithelial cells. Moreover, the concentration of IL-18 in intestinal cell lysates of 1-day-old piglets was about 3-fold and 6-fold less than that in those of 1-month-old and 6-month-old piglets, respectively. Exogenous IL-18 was able to induce interferon-gamma (IFN-gamma) in the peripheral blood of 1-day-old piglets, whereas concanavalin A (ConA) was not able to induce IFN-gamma in the same condition. These results suggest that mucosal epithelial cells are among the major sources of IL-18 in pig and that IL-18 may be useful as a therapeutic agent for the enhancement of immune responses and as a vaccine adjuvant, especially in neonatal piglets.


Asunto(s)
Interleucina-18/biosíntesis , Mucosa Intestinal/metabolismo , Porcinos/metabolismo , Tráquea/metabolismo , Factores de Edad , Animales , Animales Recién Nacidos , Ensayo de Inmunoadsorción Enzimática , Células Epiteliales/metabolismo , Interferón gamma/biosíntesis , Interferón gamma/genética , Interleucina-18/sangre , Interleucina-18/genética , Interleucina-18/farmacología , Intestino Delgado/metabolismo , Macrófagos Alveolares/metabolismo , Masculino , Membrana Mucosa/metabolismo
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