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The depletion of cellular zinc (Zn) adversely affects plant growth. Plants have adaptation mechanisms for Zn-deficient conditions, inhibiting growth through the action of transcription factors and metal transporters. We previously identified three defensin-like (DEFL) proteins (DEFL203, DEFL206 and DEFL208) that were induced in Arabidopsis thaliana roots under Zn-depleted conditions. DEFLs are small cysteine-rich peptides involved in defense responses, development and excess metal stress in plants. However, the functions of DEFLs in the Zn-deficiency response are largely unknown. Here, phylogenetic tree analysis revealed that seven DEFLs (DEFL202-DEFL208) were categorized into one subgroup. Among the seven DEFLs, the transcripts of five (not DEFL204 and DEFL205) were upregulated by Zn deficiency, consistent with the presence of cis-elements for basic-region leucine-zipper 19 (bZIP19) or bZIP23 in their promoter regions. Microscopic observation of GFP-tagged DEFL203 showed that DEFL203-sGFP was localized to the apoplast and plasma membrane. Whereas a single mutation of the DEFL202 or DEFL203 genes only slightly affected root growth, defl202 defl203 double mutants showed enhanced root growth under all growth conditions. We also showed that the size of the root meristem was increased in the double mutants compared with the wild type. Our results suggest that DEFL202 and DEFL203 are redundantly involved in the inhibition of root growth under Zn-deficient conditions through a reduction in root meristem length and cell number.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Filogenia , Zinco/metabolismo , Metais/metabolismo , Plantas/metabolismo , Defensinas/genética , Defensinas/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Raízes de Plantas/metabolismoRESUMO
A backdoor attack is a type of attack method that induces deep neural network (DNN) misclassification. The adversary who aims to trigger the backdoor attack inputs the image with a specific pattern (the adversarial mark) into the DNN model (backdoor model). In general, the adversary mark is created on the physical object input to an image by capturing a photo. With this conventional method, the success of the backdoor attack is not stable because the size and position change depending on the shooting environment. So far, we have proposed a method of creating an adversarial mark for triggering backdoor attacks by means of a fault injection attack on the mobile industry processor interface (MIPI), which is the image sensor interface. We propose the image tampering model, with which the adversarial mark can be generated in the actual fault injection to create the adversarial mark pattern. Then, the backdoor model was trained with poison data images, which the proposed simulation model created. We conducted a backdoor attack experiment using a backdoor model trained on a dataset containing 5% poison data. The clean data accuracy in normal operation was 91%; nevertheless, the attack success rate with fault injection was 83%.
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Cyclic tetraaryl[5]cumulenes (1 a-f) have been synthesized and studied as a function of increasing ring strain. The magnitude of ring strain is approximated by the extent of bending of the cumulenic core as assessed by a combination of X-ray crystallographic analysis and DFT calculations. Trends are observed in 13 C NMR, UV-vis, and Raman spectra associated with ring strain, but the effects are small. In particular, the experimental HOMO-LUMO gap is not appreciably affected by bending of the [5]cumulene framework from ca. 174° (λmax =504â nm) in 1 a to ca. 178° (λmax =494â nm) in 1 f.
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Teoria Quântica , Análise Espectral Raman , Modelos Moleculares , Polienos , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
OBJECTIVES: To compare the pathogen identification rate and use of antibiotics before and after the implementation of multiplex polymerase chain reaction testing in children with respiratory infections in a PICU. DESIGN: Single-center, pre-post study. SETTING: PICU of Osaka Women's and Children's Hospital, Osaka, Japan. PATIENTS: Consecutive children with respiratory infections who were admitted to the PICU between December 2017 and November 2018 (premultiplex polymerase chain reaction period) and between March 2019 and February 2020 (postmultiplex polymerase chain reaction period). INTERVENTIONS: Conventional rapid antigen tests and bacterial culture tests were performed throughout the study period. Multiplex polymerase chain reaction testing using the FilmArray respiratory panel (BioFire Diagnostics, Salt Lake City, UT) was conducted to detect 17 viruses and three bacterial pathogens. During the postmultiplex polymerase chain reaction period, we did not recommend prescribing antibiotics for stable children, depending on the virus species and laboratory test results. MEASUREMENTS AND MAIN RESULTS: Ninety-six and 85 children were enrolled during the pre- and postmultiplex polymerase chain reaction periods, respectively. Rapid antigen tests identified pathogens in 22% of the children (n = 21) during the premultiplex polymerase chain reaction period, whereas rapid antigen tests and/or multiplex polymerase chain reaction testing identified pathogens in 67% of the children (n = 57) during the postmultiplex polymerase chain reaction period (p < 0.001). The most commonly identified pathogen using multiplex polymerase chain reaction testing was human rhino/enterovirus. Bacterial pathogens were identified in 50% of the children (n = 48) and 60% of the children (n = 51) during the pre- and postmultiplex polymerase chain reaction periods (p = 0.18). There were no differences in antibiotic use (84% vs 75%; p = 0.14), broad-spectrum antibiotic use (33% vs 34%; p = 0.91), or the duration of antibiotic use within 14 days of admission (6.0 vs 7.0 d; p = 0.45) between the pre- and postmultiplex polymerase chain reaction periods. CONCLUSIONS: Although the pathogen identification rate, especially for viral pathogens, increased using multiplex polymerase chain reaction testing, antibiotic use did not reduce in children with respiratory infections in the PICU. Definitive identification of bacterial pathogens and implementation of evidence-based antimicrobial stewardship programs employing multiplex polymerase chain reaction testing are warranted.
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Infecções Respiratórias , Vírus , Antibacterianos/uso terapêutico , Criança , Feminino , Humanos , Unidades de Terapia Intensiva Pediátrica , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , Vírus/genéticaRESUMO
We report here the synthesis of two novel subporphyrins (SubPs), in which the macrocycle has been functionalized at its meso (1) or axial (2) position with tetracyanobuta-1,3-diene (TCBD)-aniline. In-depth spectroscopic, spectrometric, and electrochemical analyses were carried out with both of them, whose molecular structures were determined by single-crystal X-ray diffraction studies. In the case of 2, its Ra and Sa enantiomers were separable by chiral HPLC and presented a fairly good configurational stability at room temperature, which enabled determining the activation parameters for the thermally induced racemization. Conversely, the enantiomers' separation was unfeasible for 1 due to the conformational and/or configurational dynamics of the TCBD-aniline, a structural "flexibility" that could be drastically reduced at low temperatures. The physicochemical impact of placing the TCBD-aniline at either the axial or peripheral positions of SubPs is also rather significant. The HOMO-LUMO gap is reduced by as much as 0.35 eV in SubP-(TCBD-aniline)meso 1 (1.77 eV) and, in turn, enables an emissive charge-transfer (CT) state in virtually all environments. It is only in polar environments, where it links a local excitation with an indirect charge separation. In contrast, a much larger HOMO-LUMO gap of 2.12 eV in SubP-(TCBD-aniline)axial 2 disables an emissive CT state and enforces either an exciplex deactivation in apolar environments or a direct charge separation in polar environments.
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OBJECTIVES: To identify the effects of healthcare-associated infections on length of PICU stay and mortality. DESIGN: Retrospective, single-center, observational study. SETTING: PICU of a tertiary children's hospital. PATIENTS: Consecutive patients who stayed greater than 48 hours in the PICU between January 2013 and December 2017. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Data were retrospectively collected from medical records. We identified occurrences of common healthcare-associated infections, including bloodstream infection, pneumonia, and urinary tract infection, defined according to the 2008 definitions of the Centers for Disease Control and Prevention and National Healthcare Safety Network. We assessed the effects of each healthcare-associated infection on length of PICU stay and PICU mortality using multivariable analysis. Among 1,622 admissions with a PICU stay greater than 48 hours, the median age was 299 days and male patients comprised 51% of admissions. The primary diagnostic categories were cardiovascular (58% of admissions), respiratory (21%), gastrointestinal (8%), and neurologic/muscular (6%). The median length of PICU stay was 6 days, and the PICU mortality rate was 2.5%. A total of 167 healthcare-associated infections were identified, including 67 bloodstream infections (40%), 43 pneumonias (26%), and 57 urinary tract infections (34%). There were 152 admissions with at least one healthcare-associated infection (9.4% of admissions with a stay > 48 hr). On multivariable analysis, although each healthcare-associated infection was not significantly associated with mortality, bloodstream infection was associated with an extra length of PICU stay of 10.2 days (95% CI, 7.9-12.6 d), pneumonia 14.2 days (11.3-17.2 d), and urinary tract infection 6.5 days (4.0-9.0 d). Accordingly, 9.7% of patient-days were due to these three healthcare-associated infections among patients with a stay greater than 48 hours. CONCLUSIONS: Although healthcare-associated infections were not associated with PICU mortality, they were associated with extra length of PICU stay. As 9.7% of patient-days were due to healthcare-associated infections, robust prevention efforts are warranted.
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Infecção Hospitalar/mortalidade , Mortalidade Hospitalar , Unidades de Terapia Intensiva Pediátrica/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Estudos de Casos e Controles , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores de RiscoRESUMO
Boron(III) 5-arylsubporphyrins and BIII subporphine are promising precursors for functional BIII subporphyrins bearing asymmetric meso-substituents. Herein, we report the first synthesis of these molecules. Among many aryl acid chlorides examined, 4-nitrobenzoyl chloride gave BIII 5-(4-nitrophenyl)subporphyrin in 10 % yield in condensation with triethylamine-tri-N-tripyrromethene-borane. The nitro group of this BIII subporphyrin was reduced with NaBH4 to prepare BIII 5-(aminophenyl)subporphyrin, which was converted into BIII 5-phenylsubporphyrin via the corresponding diazonium salt. BIII subporphine was synthesized by condensation of triethyl orthoformate with triethylamine-tri-N-tripyrromethene-borane. Progressive removal of meso-phenyl substituents leads to continuous changes in the optical properties, whereas the BIII subporphine deviates from this trend in some properties.
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Pyrrole-modified subporphyrins bearing a non-pyrrolic cyclic unit, subporpholactone, subporpholactam, and imidazolosubporphyrin were newly synthesized. They show subporphyrin-like absorption and fluorescence spectra that are red-shifted in the order of subporpholactam
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10,15,20-Tris(pentafluorophenyl)-substituted NiII -porphyrin meso-oxy radical bearing two coordinating pyridines was synthesized as a stable radical with a quartet ground state (S=3/2). X-ray structural analysis revealed that the NiII porphyrin moiety is fairly planar and the Ni-N bond lengths are considerably longer, indicating the high-spin state of the NiII center. The radical exhibited a quartet ground state, indicating the ferromagnetic interaction between the high-spin NiII center (S=1) and the porphyrin meso-oxy radical (S=1/2).
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A pyrrole-cleaving modification to transform boron(III) meso-triphenylsubporphyrin into boron(III) meso-triphenylsubchlorophin has been developed. Boron(III) subchlorophins thus synthesized show absorption and fluorescence spectra that are roughly similar to those of boron(III) subchlorins, but B-methoxy boron(III) subchlorophin showed considerably intensified fluorescence and a small Stokes shift. Peripheral modification reactions of B-phenyl boron(III) subchlorophin such as regioselective nitration with Cu(NO3 )2 â 3 H2 O, ipso-substitution reactions of boron(III) α-nitrosubchlorophin with CsF and CsCl, and Pd-catalyzed cross-coupling reactions of boron(III) α-chlorosubchlorophin with arylacetylenes, have been also explored to tune the optical properties of subchlorophins.
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ß,ß-(1,4-Dithiino)subporphyrin dimers 7-syn and 7-anti were synthesized by the nucleophilic aromatic substitution reaction of 2-bromo-3-(4-methoxyphenylsulfonyl)subporphyrin 4 with 2,3-dimercaptosubporphyrin 5 under basic conditions followed by axial arylation. Additions of C60 or C70 to a dilute solution of 7-anti (ca. 10(-6) m) in toluene did not cause appreciable UV/Vis spectral changes, while similar additions to a concentrated solution (ca. 10(-3) m) resulted in precipitation of complexes. In contrast, dimer 7-syn captured C60 and C70 in different complexation stoichiometries in toluene; a 1:1 manner and a 2:1 manner, respectively, with large association constants; Ka =(1.9±0.2)×10(6) m(-1) for C60 @7-syn, and K1 =(1.6±0.5)×10(6) and K2 =(1.8±0.9)×10(5) m(-1) for C70 @(7-syn)2 . These association constants are the largest for fullerenes-capture by bowl-shaped molecules reported so far. The structures of C60 @7-anti, C70 @7-anti, C60 @7-syn, and C70 @7-syn have been determined by single-crystal X-ray diffraction analysis.
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Boron arylations of B-(methoxo)triphenylsubporphyrin have been developed with a combined use of ArZnIâ LiCl and trimethylsilyl chloride. Aryl zinc reagents bearing bromo, cyano, amide, and ester groups can be employed for the B-arylation reaction to provide the corresponding B-arylated subporphyrins in moderate yields. Postmodifications of B-arylated subporphyrins have been demonstrated without loss of the B-C bond. These modifications include conversion of the cyano group into a benzoyl group with PhMgBr, hydrolysis of the ester group to give B-(4-carboxyphenyl)subporphyrin, and Pd-catalyzed Suzuki-Miyaura coupling of the 4-bromophenyl group to give a 1,4-phenylene-bridged subporphyrin-ZnII porphyrin hybrid that displays intramolecular excitation energy transfer from the subporphyrin to the porphyrin. The newly synthesized B-arylated subporphyrins have been fully characterized by NMR, UV/Vis absorption and fluorescence spectroscopies, mass spectrometry, electrochemical measurements, and X-ray diffraction analysis.
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Intrinsically chiral Möbius aromatic [28]hexaphyrin monophosphorus(V) and Möbius antiaromatic [30]hexaphyrin bisphosphorus(V) complexes have been optically resolved and their absolute configurations (ACs) were determined by combined experimental and theoretical investigations on their circular dichroisms (CDs). First elutes in chiral HPLC exhibited strong positive Cotton effects (CEs) at the B-band, characteristic for the ML configurations in their Möbius strips. Weak CEs at the Q-band, if attainable, complemented their AC assignment. The whole CD pattern and intensity were well reproduced by time-dependent approximate coupled cluster theory using model systems that omit five outward meso-aryl substituents (inward-meso-retained model), providing a solid basis for AC assignment. The cost efficient TD-DFT method with appropriate functionals for fully substituted (nontruncated) complexes well reproduced CEs around the B-band (but less satisfactory at the Q-band), also allows the rapid AC estimation for their Möbius strips. Observed difference in CDs between aromatic and antiaromatic hexaphyrins were better interpreted by their shifts in energy levels and altered interactions of relevant molecular orbitals, rather than small differences in Möbius geometries nor aromatic/antiaromatic character, despite the correlations recently claimed in planar π-systems.
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B-Methoxy ß-(4-methoxyphenylsulfinyl)subporphyrin and B-phenyl ß-(4-methoxyphenylsulfinyl)subporphyrin were synthesized by oxidation of the corresponding ß-sulfanylsubporphyrins with m-chloroperbenzoic acid and were separated into diastereomers, respectively. B-Methoxy subporphyrin diastereomers were interconverted to each other in methanol or ethanol, whereas such interconversion was not observed for B-phenyl subporphyrin diastereomers even at high temperature. Diastereomeric interconversions of B-methoxy subporphyrins were dramatically accelerated by addition of trifluoroacetic acid. These results suggest that the diastereomeric interconversions of B-methoxy subporphyrins, namely, their bowl inversions, proceed via a mechanism involving protonation-induced generation of subporphyrin borenium cations followed by nucleophilic attacks by alcohols.
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A2 B-type B-methoxy subporphyrins 3 a-g and B-phenyl subporphyrins 7 a-c,e,g bearing meso-(2-substituted)aryl substituents are synthesized, and their rotational dynamics are examined through variable-temperature (VT) (1) Hâ NMR spectroscopy. In these subporphyrins, the rotation of meso-aryl substituents is hindered by a rationally installed 2-substituent. The rotational barriers determined are considerably smaller than those reported previously for porphyrins. Comparison of the rotation activation parameters reveals a variable contribution of ΔH(≠) and ΔS(≠) in ΔG(≠). 2-Methyl and 2-ethyl groups of the meso-aryl substituents in subporphyrins 3 e, 3 f, and 7 e induce larger rotational barriers than 2-alkoxyl substituents. The rotational barriers of 3 g and 7 g are reduced by the presence of the 4-dibenzylamino group owing to its ability to stabilize the coplanar rotation transition state electronically. The smaller rotational barriers found for B-phenyl subporphyrins than for B-methoxy subporphyrins indicate a negligible contribution of SN 1-type heterolysis in the rotation of meso-aryl substituents.
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Barbiturate overdose is a common method for euthanizing pigs. However, barbiturates can cause tissue damage and may affect experimental results, so the minimal dose should be used. The minimal dose of barbiturate for euthanasia in pigs under isoflurane anesthesia has not yet been determined. In this study, we compared the effect of low and high doses of 2 barbiturates (pentobarbital, 30 or 60 mg/kg; thiopental, 20 and 40 mg/kg) on hemodynamic parameters and time to cardiac arrest in female pigs maintained on isoflurane. Acute decreases in blood pressure and end-tidal CO2 occurred in all pigs shortly after administration of the barbiturate. However, these changes were not different between either of the high- and low dose groups. Cardiac arrest occurred significantly faster for high dose as compared with low dose thiopental groups, but this parameter was different between the 2 pentobarbital groups. The bispectral index fell immediately after dosing, in all pigs, but no significant differences were observed in the time needed to achieve 0 for the high or low-doses of either drug. In pigs maintained on isoflurane, a low dose of barbiturates is adequate for euthanasia and may result in less tissue damage.
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Anestesia , Isoflurano , Feminino , Animais , Suínos , Pentobarbital , Tiopental , Barbitúricos , Anestesia/veterináriaRESUMO
This report describes two cases of dextran-induced anaphylactoid reaction (DIAR), with and without cutaneous signs that appeared after administration of dextran 40 during general anesthesia in domestic pigs. Dextran was administered intravenously to 59 pigs that underwent general anesthesia for routine medical device training, and two pigs developed sudden, severe hypotension and decreased end-tidal CO2 level and arterial oxygen saturation within a few minutes after the start of dextran 40 infusion. A systemic cutaneous lesion presenting as flushing and urticaria was observed in case 1, whereas no skin lesions were found despite persistent observation in case 2. Cases 1 and 2 recovered with thoracic wall compression and an intravenous injection of epinephrine (0.02 mg) and hydrocortisone sodium succinate (250 mg). After DIAR treatment, no complications were observed, and the pigs were euthanized with an intravenous injection of thiopental sodium (1.0 g) when the training program was completed. This case report discusses the appearance of DIAR after dextran 40 administration during general anesthesia in domestic pigs, which is similar to DIAR in humans. However, the incidence of DIAR in this study was much higher than that in humans, suggesting that dextran 40 should not be used in domestic pigs.
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Anafilaxia , Anafilaxia/induzido quimicamente , Anestesia Geral/efeitos adversos , Anestesia Geral/veterinária , Animais , Dextranos/efeitos adversos , Humanos , Saturação de Oxigênio , Sus scrofa , SuínosRESUMO
A2B-type meso-(4-nitrophenyl)-substituted subporphyrins have been synthesized and shown to undergo very fast photoinduced intramolecular charge separation (CS) and charge recombination (CR) between the subporphyrin core and the meso-4-nitrophenyl group in CH2Cl2 as probed by femtosecond time-resolved transient absorption spectroscopy. Red-shifted emissions were detected from charge-separated states as a rare case for porphyrinoids.
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Porfirinas/química , Cristalografia por Raios X , Elétrons , Espectrometria de MassasRESUMO
Peripherally hexachlorinated meso-triphenyl subporphyrin 4 was prepared by chlorination of meso-triphenyl subporphyrin 1 with N-chlorosuccinimide and was effectively transformed to hexasulfanylated subporphyrins 5-8 via nucleophilic aromatic substitution (S(N)Ar) reactions with the corresponding thiols under basic conditions. The structures of 5-8 have been all well characterized by single-crystal X-ray analysis. (1)Hâ NMR studies indicated that the meso-phenyl substituents undergo restricted rotation for 5-8, while the ß-sulfanyl substituents are conformationally flexible in 5, 6, and 8, and are strictly regulated to an anti-conformation in 7. Judging from the absorption spectra, the oxidation and reduction potentials, and the DFT calculations, the substituent effects decrease in the order of 5>6>7>8. Subporphyrin 8 effectively captures C60 in a 1:1 manner in [D8 ]toluene solution.
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Epithelial-mesenchymal transition (EMT) is a crucial step in tumour progression. However, the molecular mechanisms underlying EMT in canine tumours remain to be elucidated. In this study, the similarity or difference in the molecular mechanism of EMT in canine cells was evaluated and compared with that reported in human and mouse cells. We used eight cell lines derived from canine mammary cancers. Stimulation with hepatocyte growth factor (HGF) increased cell motility and changed EMT-related markers towards mesenchyme in CHMm cell line. These changes were accompanied by an increase in Twist expression and did not occur in CHMm transfected with Twist siRNA, indicating that Twist plays a key role in this phenomenon in CHMm. However, the down-regulation of E-cadherin was not observed by HGF stimulation. Further studies are required to elucidate the difference between human and canine Twist.