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1.
J Phys Condens Matter ; 31(44): 445804, 2019 Nov 06.
Article in English | MEDLINE | ID: mdl-31392970

ABSTRACT

We report a combined study of imaging the antiferromagnetic (AFM) spin structure and measuring the spin Hall magnetoresistance (SMR) in epitaxial thin films of the insulating non-collinear antiferromagnet SmFeO3. X-ray magnetic linear dichroism photoemission electron microscopy measurements reveal that the AFM spins of the SmFeO3(1 1 0) align in the plane of the film. Angularly dependent magnetoresistance measurements show that SmFeO3/Ta bilayers exhibit a positive SMR, in contrast to the negative SMR expected in previously studied collinear AFMs. The SMR amplitude increases linearly with increasing external magnetic field at higher magnetic fields, suggesting that field-induced canting of the AFM spins plays an important role. In contrast, around the coercive field, no detectable SMR signal is observed, indicating that the SMR of the AFM and canting magnetization components cancel out. Below 50 K, the SMR amplitude increases sizably by a factor of two as compared to room temperature, which likely correlates with the long-range ordering of the Sm ions. Our results show that the SMR is a sensitive technique for non-equilibrium spin systems of non-collinear AFMs.

2.
Br J Anaesth ; 122(3): 379-387, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30770056

ABSTRACT

BACKGROUND: An injectable liposomal bupivacaine suspension (EXPAREL™) is approved by the US Food and Drug Administration for analgesia by tissue infiltration and interscalene brachial plexus, but not for use in the neuraxial space. This pilot study describes neurological and histological outcomes of escalating doses of this extended-release formulation of bupivacaine after subarachnoid administration. METHODS: Twenty-five pigs (Sus scrofa domesticus) weighing 36.2 (4.4) kg were randomly assigned to one of five groups to receive a subarachnoid injection of sodium chloride 0.9%, 3 ml (negative control), preservative-free bupivacaine hydrochloride 0.5%, 3 ml (positive control), or one of three doses of liposomal bupivacaine suspension 1.33%: 1.5, 3, or 5 ml. After recovering from general anaesthesia, neurological outcomes were assessed by blinded observers. Three weeks later, the animals were sacrificed for histological evaluations of neurotoxicity. RESULTS: Animals that received sodium chloride 0.9%, bupivacaine hydrochloride, or liposomal bupivacaine 1.5 ml recovered within 2, 5, or 4 h, respectively. Animals that received liposomal bupivacaine 3 or 5 ml exhibited signs of neuraxial block (decreased nociception and proprioception) up to 32 h after injection. No histological evidence of neurotoxicity was found in any of the groups. CONCLUSIONS: Subarachnoid administration of liposomal bupivacaine in pigs exhibited a dose-response effect, and resulted in longer duration of neuraxial block than bupivacaine hydrochloride without histological evidence of neurotoxicity. Our study contributes preliminary data to inform further toxicological assessments and regulatory approval before subarachnoid administration in humans.


Subject(s)
Anesthetics, Local/administration & dosage , Anesthetics, Local/adverse effects , Bupivacaine/administration & dosage , Bupivacaine/adverse effects , Neurotoxicity Syndromes/etiology , Animals , Bupivacaine/analogs & derivatives , Delayed-Action Preparations , Disease Models, Animal , Dose-Response Relationship, Drug , Injections, Spinal , Pilot Projects , Subarachnoid Space , Swine
3.
Malays J Pathol ; 41(3): 339-343, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31901919

ABSTRACT

INTRODUCTION: Cribriform-morular variant (CMV) is a rare variant of papillary thyroid carcinoma. It frequently occurs in association with familial adenomatous polyposis (FAP), although some cases are sporadic. Herein, we report a case of CMV and analyse morule cytohistology. CASE REPORT: The patient was a 47-year-old woman with no familial history of FAP. A 3.0-cm unifocal mass was identified in the left thyroidal lobe. Fine-needle aspiration cytology revealed papillary clusters of atypical cells with nuclear grooves, which was suspected to be conventional papillary thyroid carcinoma. Histologically, the tumour comprised a papillary and cribriform growth of atypical cells with cytoplasmic accumulation and nuclear translocation of b-catenin. In addition, frequent morule formation was identified. DISCUSSION: In this case, we performed morule analysis through correlative light and electron microscopy (CLEM), and revealed its ultrastructure. Although CMV is a rare form of thyroid carcinoma, it should be considered along with its distinct clinicopathological characteristics.


Subject(s)
Carcinoma, Papillary/pathology , Thyroid Cancer, Papillary/pathology , Thyroid Gland/pathology , Thyroid Neoplasms/pathology , Adenomatous Polyposis Coli/pathology , Biopsy, Fine-Needle , Carcinoma/diagnosis , Carcinoma/pathology , Carcinoma, Papillary/diagnosis , Female , Humans , Middle Aged , Thyroid Cancer, Papillary/diagnosis , Thyroid Neoplasms/diagnosis
4.
Anaesthesia ; 74(1): 22-28, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30288741

ABSTRACT

Cricoid force is widely applied to decrease the risk of pulmonary aspiration and gastric antral insufflation of air during positive-pressure ventilation, yet its efficacy remains controversial. We compared manual oesophageal compression at the low left paratracheal and cricoid levels for the prevention of gastric antral air insufflation during positive-pressure ventilation by facemask in patients scheduled for elective surgery under general anaesthesia. After gaining written consent, participants were randomly allocated by sealed envelope to one of three groups: oesophageal compression by 30 N paratracheal force (paratracheal group); oesophageal compression by 30 N cricoid force (cricoid group); or no oesophageal compression (control group). Gastric insufflation of air was assessed before and after positive-pressure ventilation by ultrasound measurement of the antral cross-sectional area and/or presence of air artefacts in the antrum. The primary outcome measure was the proportion of participants with ultrasound evidence of gastric insufflation. We recruited 30 patients into each group. Before facemask ventilation, no air artefacts were visible in the antrum in any of the participants. After facemask ventilation of the participant's lungs, no air artefacts were seen in the paratracheal group, compared with six subjects in the cricoid group and eight subjects in the control group (p = 0.012). Our results suggest that oesophageal compression can be achieved by the application of manual force at the low left paratracheal level and that this is more effective than cricoid force in preventing air entry into the gastric antrum during positive-pressure ventilation by facemask.


Subject(s)
Esophagus/physiology , Insufflation/methods , Positive-Pressure Respiration , Pyloric Antrum , Adolescent , Adult , Aged , Anesthesia, General , Cricoid Cartilage/physiology , Female , Humans , Male , Middle Aged , Pressure , Pyloric Antrum/diagnostic imaging , Ultrasonography , Young Adult
5.
Clin. transl. oncol. (Print) ; 19(10): 1232-1240, oct. 2017. tab, graf
Article in English | IBECS | ID: ibc-166156

ABSTRACT

Purpose. Stage shift is considered a major reason for more favorable outcomes in patients with screen-detected breast cancer. However, even after adjusting for clinical stage, unresolved issues concerning the reasons for a survival benefit associated with screening programs remain. This study aims to evaluate differences in subtype distribution and outcomes among patients with screen-detected and symptomatic invasive breast cancer and assess whether variations in subtype distribution could explain differences in prognosis. Methods. Survival analysis was performed to estimate the likelihood of distant recurrence and death in 1132 patients. Subtypes were defined as luminal A [estrogen receptor (ER)+ and/or progesterone receptor (PR)+, human epidermal growth factor receptor 2 (HER2)-, and Ki67 low], luminal B (HER2-) (ER+ and/or PR+, HER2-, and Ki67 high), luminal B (HER2+) (ER+ and/or PR+ and HER2+), HER2 overexpressing (ER-, PR-, and HER2+), and triple negative (ER-, PR-, and HER2-). Results. Screen-detected cancers had favorable clinicopathological characteristics, such as smaller tumor size and a lower frequency of lymph node involvement. Women with screen-detected cancers had a survival advantage. Subtype distribution differed significantly among women with screen-detected and symptomatic cancer. Screen-detected cancers were more likely to be luminal A and less likely to be HER2 overexpressing or triple negative cancer compared with symptomatic cancers (luminal A 61.3 vs. 44.2%, HER2 overexpressing 4.0 vs. 8.0%, triple negative 8.0 vs. 15.9%). Node status, mode of detection, and subtype were independent prognostic factors in the multivariate analysis. Conclusions. Differences in subtype distribution between screen-detected and symptomatic cancer could partially explain differences in outcomes (AU)


No disponible


Subject(s)
Humans , Female , Breast Neoplasms/classification , Breast Neoplasms/complications , Breast Neoplasms/diagnosis , Disease-Free Survival , Survivorship , Prognosis , Immunohistochemistry/methods , Immunohistochemistry , 28599 , Biomarkers/analysis
6.
Water Sci Technol ; 76(5-6): 1418-1428, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28953468

ABSTRACT

Duckweed offers the promise of a co-benefit culture combining water purification with biomass production. Acinetobacter calcoaceticus P23 is a plant growth-promoting bacterium isolated from a duckweed, Lemna aequinoctialis. This study quantified its growth-promoting effect on three duckweeds (L. aoukikusa, L. minor, and Spirodela polyrhiza) in sterile Hoagland solution and evaluated its usefulness in duckweed culture under non-sterile conditions. P23 promoted growth of three duckweeds in sterile Hoagland solution at low to high nutrient concentrations (1.25-10 mg NO3-N/L and 0.25-2.0 mg PO4-P/L). It increased the biomass production of L. aequinoctialis 3.8-4.3-fold, of L. minor 2.3-3.3-fold, and of S. polyrhiza 1.4-1.5-fold after 7 days compared with noninoculated controls. P23 also increased the biomass production of L. minor 2.4-fold in pond water and 1.7-fold in secondary effluent of a sewage treatment plant under non-sterile conditions at laboratory-scale experiments. P23 rescued L. minor from growth inhibition caused by microorganisms indigenous to the pond water. The results demonstrate that the use of P23 in duckweed culture can improve the efficiency of duckweed biomass production, and a positive effect of P23 on duckweed-based wastewater treatment can be assumed.


Subject(s)
Acinetobacter calcoaceticus/physiology , Araceae/growth & development , Araceae/microbiology , Biomass , Wastewater , Water Purification/methods , Fresh Water , Plant Development , Water Pollutants, Chemical/chemistry
7.
Clin Transl Oncol ; 19(10): 1232-1240, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28409323

ABSTRACT

PURPOSE: Stage shift is considered a major reason for more favorable outcomes in patients with screen-detected breast cancer. However, even after adjusting for clinical stage, unresolved issues concerning the reasons for a survival benefit associated with screening programs remain. This study aims to evaluate differences in subtype distribution and outcomes among patients with screen-detected and symptomatic invasive breast cancer and assess whether variations in subtype distribution could explain differences in prognosis. METHODS: Survival analysis was performed to estimate the likelihood of distant recurrence and death in 1132 patients. Subtypes were defined as luminal A [estrogen receptor (ER)+ and/or progesterone receptor (PR)+, human epidermal growth factor receptor 2 (HER2)-, and Ki67 low], luminal B (HER2-) (ER+ and/or PR+, HER2-, and Ki67 high), luminal B (HER2+) (ER+ and/or PR+ and HER2+), HER2 overexpressing (ER-, PR-, and HER2+), and triple negative (ER-, PR-, and HER2-). RESULTS: Screen-detected cancers had favorable clinicopathological characteristics, such as smaller tumor size and a lower frequency of lymph node involvement. Women with screen-detected cancers had a survival advantage. Subtype distribution differed significantly among women with screen-detected and symptomatic cancer. Screen-detected cancers were more likely to be luminal A and less likely to be HER2 overexpressing or triple negative cancer compared with symptomatic cancers (luminal A 61.3 vs. 44.2%, HER2 overexpressing 4.0 vs. 8.0%, triple negative 8.0 vs. 15.9%). Node status, mode of detection, and subtype were independent prognostic factors in the multivariate analysis. CONCLUSIONS: Differences in subtype distribution between screen-detected and symptomatic cancer could partially explain differences in outcomes.


Subject(s)
Biomarkers, Tumor/metabolism , Breast Neoplasms/mortality , Early Detection of Cancer/mortality , Receptor, ErbB-2/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Female , Follow-Up Studies , Humans , Middle Aged , Neoplasm Invasiveness , Prognosis , Retrospective Studies , Survival Rate
8.
Br J Dermatol ; 177(4): 1122-1126, 2017 Oct.
Article in English | MEDLINE | ID: mdl-27925156

ABSTRACT

Here we report a rare case of neutrophilic dermatoses related to a granulocyte colony-stimulating factor (G-CSF)-producing solid pseudopapillary tumour (SPT). The patient was a 39-year-old woman presenting with scattered pustules and crusts of the palms, heels and thighs and plaques of the bilateral lower legs. The skin biopsy revealed dense neutrophil infiltration in the epidermis to the dermis. A pancreatic head tumour was detected using computed tomography. A pathological examination of the resected specimen suggested an SPT. As the skin eruption promptly disappeared after SPT resection, we hypothesized that SPT secretes growth factors including epidermal growth factor (EGF) and G-CSF. The SPT cells stained positive for both EGF and G-CSF tumour cells. The serum levels of interleukin (IL)-6 and IL-10 and tumour necrosis factor-α were within normal limits before and after the SPT resection. In contrast, the serum IL-8, EGF and G-CSF levels decreased after the SPT resection. This is a rare case of neutrophilic dermatoses related to a G-CSF-producing SPT. The present case suggests that physicians should be aware that a G-CSF-producing tumour is a differential diagnosis to consider in patients with unusual aseptic pustulosis.


Subject(s)
Carcinoma, Papillary/complications , Granulocyte Colony-Stimulating Factor/biosynthesis , Pancreatic Neoplasms/complications , Skin Diseases/etiology , Adult , Female , Humans , Leg
10.
Vet Pathol ; 53(2): 277-90, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26869153

ABSTRACT

Aging is the biological process of declining physiologic function associated with increasing mortality rate during advancing age. Humans and higher nonhuman primates exhibit unusually longer average life spans as compared with mammals of similar body mass. Furthermore, the population of humans worldwide is growing older as a result of improvements in public health, social services, and health care systems. Comparative studies among a wide range of organisms that include nonhuman primates contribute greatly to our understanding about the basic mechanisms of aging. Based on their genetic and physiologic relatedness to humans, nonhuman primates are especially important for better understanding processes of aging unique to primates, as well as for testing intervention strategies to improve healthy aging and to treat diseases and disabilities in older people. Rhesus and cynomolgus macaques are the predominant monkeys used in studies on aging, but research with lower nonhuman primate species is increasing. One of the priority topics of research about aging in nonhuman primates involves neurologic changes associated with cognitive decline and neurodegenerative diseases. Additional areas of research include osteoporosis, reproductive decline, caloric restriction, and their mimetics, as well as immune senescence and chronic inflammation that affect vaccine efficacy and resistance to infections and cancer. The purpose of this review is to highlight the findings from nonhuman primate research that contribute to our understanding about aging and health span in humans.


Subject(s)
Aging/pathology , Primates/physiology , Research , Aging/genetics , Animals , Humans , Macaca fascicularis , Macaca mulatta , Models, Animal , Primates/genetics
11.
J Fish Dis ; 39(6): 667-72, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26096292

ABSTRACT

Foodborne disease outbreaks caused by raw olive flounders (Paralichthys olivaceus) parasitized with Kudoa septempunctata have been reported in Japan. Origins of olive flounders consumed in Japan vary, being either domestic or imported, and aquaculture-raised or natural. Although it is unknown whether different sources are associated with different outcomes, it is desirable to identify whether this is the case by determining whether unique K. septempunctata strains occur and if so, whether some are associated with foodborne illness. We here developed an intraspecific genotyping method, using the sequence variation of mitochondrial genes. We collected olive flounder samples from foodborne disease outbreaks, domestic fish farms or quarantine offices and investigated whether K. septempunctata genotype is associated with pathogenicity or geographic origin. The 104 samples were classified into three genotypes, ST1, ST2 and ST3. Frequency of symptomatic cases differed by genotypes, but the association was not statistically significant. Whereas K. septempunctata detected from aquaculture-raised and natural fish from Japan were either ST1 or ST2, those from fish inspected at quarantine from Korea to Japan were ST3. Our method can be applied to phylogeographic analysis of K. septempunctata and contribute to containing the foodborne disease. The genotype database is hosted in the PubMLST website (http://pubmlst.org/kseptempunctata/).


Subject(s)
Fish Diseases/epidemiology , Foodborne Diseases/epidemiology , Myxozoa/genetics , Parasitic Diseases, Animal/epidemiology , Seafood/poisoning , Animals , Fish Diseases/parasitology , Flatfishes , Foodborne Diseases/parasitology , Genetic Variation , Genome, Mitochondrial , Geography , Humans , Incidence , Japan/epidemiology , Myxozoa/classification , Parasitic Diseases, Animal/parasitology , Republic of Korea/epidemiology , Seasons , Sequence Analysis, DNA/veterinary
12.
Water Sci Technol ; 72(8): 1294-300, 2015.
Article in English | MEDLINE | ID: mdl-26465298

ABSTRACT

A novel process by using chemical leaching followed by bacterial reductive precipitation was proposed for selenium recovery from kiln powder as a byproduct of cement manufacturing. The kiln powder at a slurry concentration of 10 w/v% with 0.25 M Na2CO3 at 28°C produced wastewater containing about 30 mg-Se/L selenium. The wastewater was diluted four-fold and adjusted to pH 8.0 as preconditioning for bioreduction. A bacterial strain Pseudomonas stutzeri NT-I, capable of reducing selenate and selenite into insoluble elemental selenium, could recover about 90% selenium from the preconditioned wastewater containing selenium of 5 mg-Se/L when supplemented with lactate or glycerol. The selenium concentrations in the treated wastewater were low around the regulated effluent concentration of 0.1 mg-Se/L in Japan.


Subject(s)
Pseudomonas stutzeri/metabolism , Selenic Acid/metabolism , Selenium/isolation & purification , Chemical Precipitation , Industrial Waste , Japan , Oxidation-Reduction , Selenium/metabolism , Selenium Compounds , Wastewater
13.
Eur J Gynaecol Oncol ; 36(2): 192-6, 2015.
Article in English | MEDLINE | ID: mdl-26050359

ABSTRACT

AIMS: For the screening of cervical abnormalities, human papillomavirus (HPV) DNA testing is widely used along with Papanicolaou (Pap) testing. Although the sensitivity of the HPV DNA testing is good, its specificity is relatively low. In the present study, the authors evaluated the use of the Gen-Probe APTIMA HPV Assay for the detection of HPV mRNA and compared it with HPV DNA testing. MATERIALS AND METHODS: Liquid cervical Pap specimens collected from 410 women were assessed using the APTIMA test, the Qiagen Hybrid Capture 2 HPV DNA (HC2) Test, and the AMPLICOR HPV Test. RESULTS: The sensitivity and specificity for the detection of high-risk HPV were 85.6% and 99.2% for the APTIMA test, 94.1% and 98.4% for the HC2 test, and 90.2% and 95.7% for the AMPLICOR test, respectively. As the severity of the cervical lesion progressed, the positive rate of the three tests indicated a similar increase. The clinical sensitivity and specificity for the detection of squamous intraepithelial lesion (SIL) were 91.2% and 84.2% for the APTIMA test, 94.5% and 80.4% for the HC2 test, and 87.9% and 78.2% for the AMPLICOR test, respectively. CONCLUSION: The APTIMA is sensitive and specific for the detection of high-risk HPV. In the specimens with SIL, the APTIMA test is more specific than the HC2 and the AMPLICOR tests. This indicates that the APTIMA test may improve patient management and reduce the cost of screening.


Subject(s)
Papillomaviridae/isolation & purification , RNA, Messenger/analysis , RNA, Viral/analysis , Uterine Cervical Dysplasia/virology , Uterine Cervical Neoplasms/virology , Adult , Aged , DNA, Viral/analysis , Female , Humans , Middle Aged , Papanicolaou Test , Papillomaviridae/genetics , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Dysplasia/diagnosis
14.
Nano Lett ; 15(4): 2391-5, 2015 Apr 08.
Article in English | MEDLINE | ID: mdl-25793915

ABSTRACT

The piezoelectronic transistor (PET) has been proposed as a transduction device not subject to the voltage limits of field-effect transistors. The PET transduces voltage to stress, activating a facile insulator-metal transition, thereby achieving multigigahertz switching speeds, as predicted by modeling, at lower power than the comparable generation field effect transistor (FET). Here, the fabrication and measurement of the first physical PET devices are reported, showing both on/off switching and cycling. The results demonstrate the realization of a stress-based transduction principle, representing the early steps on a developmental pathway to PET technology with potential to contribute to the IT industry.

15.
Clin Genet ; 88(2): 155-60, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25046119

ABSTRACT

In current practice of clinical genetics, molecular diagnosis has become more widely used than ever before. DNA diagnosis is important for appropriate medical care of the patient, and proper genetic counseling to the family. However, genetic testing of orphan disease cannot always be performed easily. In multiple congenital anomalies (MCA) syndromes by monogenic cause, the broad mutational spectrum and large size of responsible genes often make molecular diagnosis expensive and cumbersome. We solve this problem with on-demand genetic testing by CHIPS (CEL nuclease mediated heteroduplex incision with polyacrylamide gel electrophoresis and silver staining) technology, which is the ultimately conventional and economical mutation screening system. In this article, we show eight patients with MCA syndromes who were recently treated at our hospital, and demonstrate that CHIPS successfully offers efficient and inexpensive genetic testing and facilitates clinical genetic service in our local region.


Subject(s)
Abnormalities, Multiple/diagnosis , Genetic Testing/methods , Molecular Diagnostic Techniques/methods , Oligonucleotide Array Sequence Analysis/methods , Abnormalities, Multiple/genetics , Adult , Child , Female , Genetic Counseling , Humans , Infant , Infant, Newborn , Male , Mutation/genetics
16.
Gene Ther ; 22(2): 127-37, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25503692

ABSTRACT

Age-related macular degeneration (AMD) is a vision-threatening disease characterized by choroidal fibrovascular membrane (FVM) formation, choroidal neovascularization (CNV) and choroidal fibrosis. No safe and effective therapeutic method has been developed for the choroidal fibrosis, although anti-vascular endothelial growth factor therapy can partially shrink the CNV. We recently reported that periostin (POSTN), which is produced by retinal pigment epithelial cells, has an important role in the formation of preretinal FVMs, but its role in choroidal FVMs has not been determined. In this study, we used Postn knockout mice to investigate the role played by POSTN in choroidal FVM formation. In addition, we used a new class of RNA interference (RNAi) agent (NK0144) that targets POSTN and determined its effect on choroidal FVM development. Genetic ablation of Postn had an inhibitory effect not only on CNV formation but also on choroidal fibrosis in a mouse CNV model. NK0144 also had a greater inhibitory effect on both the CNV and choroidal fibrosis than control RNAi with no apparent adverse effects. These findings suggest a causal relationship between POSTN and choroidal FVM formation, and also a potential therapeutic role of intravitreal NK0144 for AMD.


Subject(s)
Cell Adhesion Molecules/genetics , Choroidal Neovascularization/therapy , Macular Degeneration/therapy , RNA Interference , Animals , Base Sequence , Cell Adhesion , Cell Adhesion Molecules/metabolism , Cell Movement , Cell Proliferation , Cells, Cultured , Choroid/blood supply , Choroid/pathology , Gene Knockdown Techniques , Genetic Therapy , Humans , Intravitreal Injections , Mice, Inbred C57BL , Mice, Knockout , Molecular Sequence Data , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/genetics , Retinal Pigment Epithelium/pathology , Retinal Pigment Epithelium/physiology , Toll-Like Receptor 3/metabolism
17.
Nano Lett ; 13(10): 4650-3, 2013 Oct 09.
Article in English | MEDLINE | ID: mdl-24016226

ABSTRACT

Sophisticated microelectromechanical systems for device and sensor applications have flourished in the past decade. These devices exploit piezoelectric, capacitive, and piezoresistive effects, and coupling between them. However, high-performance piezoresistivity (as defined by on/off ratio) has primarily been observed in macroscopic single crystals. In this Letter, we show for the first time that rare-earth monochalcogenides in thin film form can modulate a current by more than 1000 times due to a pressure-induced insulator to metal transition. Furthermore, films as thin as 8 nm show a piezoresistive response. The combination of high performance and scalability make these promising candidates for nanoscale applications, such as the recently proposed piezoelectronic transistor (PET). The PET would mechanically couple a piezoelectric thin film with a piezoresistive switching layer, potentially scaling to higher speeds and lower powers than today's complementary metal-oxide-semiconductor technology.


Subject(s)
Membranes, Artificial , Metals, Rare Earth/chemistry , Semiconductors , Micro-Electrical-Mechanical Systems , Oxides/chemistry
18.
Science ; 341(6153): 1514-7, 2013 Sep 27.
Article in English | MEDLINE | ID: mdl-24030491

ABSTRACT

The global epidemic of multidrug-resistant Salmonella Typhimurium DT104 provides an important example, both in terms of the agent and its resistance, of a widely disseminated zoonotic pathogen. Here, with an unprecedented national collection of isolates collected contemporaneously from humans and animals and including a sample of internationally derived isolates, we have used whole-genome sequencing to dissect the phylogenetic associations of the bacterium and its antimicrobial resistance genes through the course of an epidemic. Contrary to current tenets supporting a single homogeneous epidemic, we demonstrate that the bacterium and its resistance genes were largely maintained within animal and human populations separately and that there was limited transmission, in either direction. We also show considerable variation in the resistance profiles, in contrast to the largely stable bacterial core genome, which emphasizes the critical importance of integrated genotypic data sets in understanding the ecology of bacterial zoonoses and antimicrobial resistance.


Subject(s)
Drug Resistance, Multiple, Bacterial/genetics , Host-Pathogen Interactions , Salmonella Infections, Animal/microbiology , Salmonella Infections/microbiology , Salmonella typhimurium/classification , Zoonoses/microbiology , Animals , Epidemics , Genome, Bacterial , Humans , Molecular Sequence Data , Phylogeny , Salmonella Infections/epidemiology , Salmonella Infections, Animal/epidemiology , Salmonella typhimurium/drug effects , Salmonella typhimurium/genetics
19.
Infect Genet Evol ; 19: 200-4, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23892035

ABSTRACT

Genome analysis of Mycobacterium leprae strain Kyoto-2 in this study revealed characteristic nucleotide substitutions in gene ML0411, compared to the reference genome M. leprae strain TN. The ML0411 gene of Kyoto-2 had six SNPs compared to that of TN. All SNPs in ML0411 were non-synonymous mutations that result in amino acid replacements. In addition, a seventh SNP was found 41 bp upstream of the start codon in the regulatory region. The seven SNP sites in the ML0411 region were investigated by sequencing in 36 M. leprae isolates from the Leprosy Research Center in Japan. The SNP pattern in 14 of the 36 isolates showed similarity to that of Kyoto-2. Determination of the standard SNP types within the 36 stocked isolates revealed that almost all of the Japanese strains belonged to SNP type III, with nucleotide substitutions at position 14676, 164275, and 2935685 of the M. leprae TN genome. The geographical distribution pattern of east Asian M. leprae isolates by discrimination of ML0411 SNPs was investigated and interestingly turned out to be similar to that of tandem repeat numbers of GACATC in the rpoT gene (3 copies or 4 copies), which has been established as a tool for M. leprae genotyping. All seven Korean M. leprae isolates examined in this study, as well as those derived from Honshu Island of Japan, showed 4 copies of the 6-base tandem repeat plus the ML0411 SNPs observed in M. leprae Kyoto-2. They are termed Northeast Asian (NA) strain of M. leprae. On the other hand, many of isolates derived from the Okinawa Islands of Japan and from the Philippines showed 3 copies of the 6-base tandem repeat in addition to the M. leprae TN ML0411 type of SNPs. These results demonstrate the existence of M. leprae strains in Northeast Asian region having characteristic SNP patterns.


Subject(s)
Antigens, Bacterial/genetics , Genes, Bacterial/genetics , Leprosy/microbiology , Mycobacterium leprae/genetics , Asia, Southeastern/epidemiology , DNA, Bacterial/analysis , DNA, Bacterial/genetics , Humans , Japan/epidemiology , Leprosy/epidemiology , Mutation/genetics , Mycobacterium leprae/isolation & purification , Polymorphism, Single Nucleotide/genetics , Republic of Korea/epidemiology
20.
Science ; 340(6130): 273, 2013 Apr 19.
Article in English | MEDLINE | ID: mdl-23599463

ABSTRACT

Conrad et al. (Reports, 10 August 2012, p. 742) reported a doubling of RNA polymerase II (Pol II) occupancy at X-linked promoters to support 5' recruitment as the key mechanism for dosage compensation in Drosophila. However, they employed an erroneous data-processing step, overestimating Pol II differences. Reanalysis of the data fails to support the authors' model for dosage compensation.


Subject(s)
DNA Polymerase II/metabolism , Dosage Compensation, Genetic , Drosophila Proteins/metabolism , Drosophila/genetics , Genes, X-Linked , Promoter Regions, Genetic , X Chromosome/genetics , Animals , Female , Male
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