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1.
Phys Rev Lett ; 133(4): 046701, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39121432

RESUMO

Utilizing spin pumping, we present a comparative study of the spin-charge conversion in RuO_{2}(101) and RuO_{2}(110) films. RuO_{2}(101) shows a robust in-plane crystal-axis dependence, whereas RuO_{2}(110) exhibits an isotropic but stronger one. Symmetry-based analysis and first-principles calculations reveal that the spin-charge conversion in RuO_{2}(110) originates from the inverse spin Hall effect (ISHE) due to nodal lines splitting. In RuO_{2}(101), the ISHE also dominates although the inverse spin splitting effect (ISSE) may coexist. These findings, in sharp contrast to previously attributed ISSE, are further corroborated by the reciprocal relation between the spin pumping and the spin-torque ferromagnetic resonance measurements.

2.
Phys Rev Lett ; 129(9): 097203, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36083669

RESUMO

In a joint effort of both experiments and first-principles calculations, we resolve a hotly debated controversy and provide a coherent picture on the pure spin transport between Ag/Bi and ferromagnets. We demonstrate a strong inverse Rashba-Edelstein effect (IREE) at the interface in between Ag/Bi with a ferromagnetic metal (FM) but not with a ferromagnetic insulator. This is in sharp contrast to the previously claimed IREE at Ag/Bi interface or inverse spin Hall effect dominated spin transport. A more than one order of magnitude modulation of IREE signal is realized for different Ag/Bi-FM interfaces, casting strong tunability and a new direction for searching efficient spintronics materials.

3.
Phys Rev Lett ; 120(4): 047201, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29437452

RESUMO

We clarify the physical origin of the dc voltage generation in a bilayer of a conducting polymer film and a micrometer-thick magnetic insulator Y_{3}Fe_{5}O_{12} (YIG) film under ferromagnetic resonance and/or spin wave excitation conditions. The previous attributed mechanism, the inverse spin Hall effect in the polymer [Nat. Mater. 12, 622 (2013)NMAACR1476-112210.1038/nmat3634], is excluded by two control experiments. We find an in-plane temperature gradient in YIG which has the same angular dependence with the generated voltage. Both vanish when the YIG thickness is reduced to a few nanometers. Thus, we argue that the dc voltage is governed by the Seebeck effect in the polymer, where the temperature gradient is created by the nonreciprocal magnetostatic surface spin wave propagation in YIG.

4.
Phys Rev Lett ; 120(9): 097001, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29547312

RESUMO

Single monolayer FeSe film grown on a Nb-doped SrTiO_{3}(001) substrate shows the highest superconducting transition temperature (T_{C}∼100 K) among the iron-based superconductors (iron pnictides), while the T_{C} value of bulk FeSe is only ∼8 K. Although bulk FeSe does not show antiferromagnetic order, calculations suggest that the parent FeSe/SrTiO_{3} films are antiferromagnetic. Experimentally, because of a lack of a direct probe, the magnetic state of FeSe/SrTiO_{3} films remains mysterious. Here, we report direct evidence of antiferromagnetic order in the parent FeSe/SrTiO_{3} films by the magnetic exchange bias effect measurements. The magnetic blocking temperature is ∼140 K for a single monolayer film. The antiferromagnetic order disappears after electron doping.

5.
Zhonghua Fu Chan Ke Za Zhi ; 53(11): 742-748, 2018 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-30453420

RESUMO

Objective: To explore the relationship between endometrial thickness and clinical pregnancy outcomes in frozen-thawed embryo transfer cycles. Methods: A prospective study was performed for 1 475 frozen-thawed embryo transfer cycles at Peking University People's Hospital from January 2014 to December 2015. The patients were divided into different groups according to endometrial thickness of ovulation day in natural menstrual cycles or endometrial transformation day in hormone replacement cycles;patients with thin endometrium were enndometrial thickness ≤6 mm. Then the clinical pregnancy outcomes including clinical pregnancy rate, embryo implantation rate, abortion rate, multiple birth rate and live birth rate were analyzed. Results: In all, 1 475 frozen-thawed embryo transfer cycles were analyzed. The mean age of patients was (32.5±3.9) years old and mean endometrial thickness was (9.2±1.9) mm, and mean number of embryos was 2.03±0.37. The study included 518 (35.1%) natural menstrual cycles and 957 (64.9%) hormone replacement cycles. The number of embryo-transfer cycles and blastocyst-transfer cycles were respectively 700 (47.5%) and 775 (52.5%) . The overall clinical pregnancy rate, embryo implantation rate, abortion rate, multiple birth rate and live birth rate were 54.4%, 35.7%, 23.3%, 24.1%, 43.9%, respectively. The ectopic pregnancy rate in the study was 0.6%. In patients with thin endometrium,there were significant differences in 2 pronucleus count (P=0.016) and available embryo count (P=0.024) between cycles that resulted in pregnancy and those that did not;besides, the use of sildenafil and growth hormone did not improve pregnancy outcomes in patients with thin endometrium (P=0.183, P=0.400) . The clinical pregnancy rate, embryo implantation rate and live birth rate of embryo-transfer and blastocyst-transfer were similar in patients with thin endometrium (all P>0.05) . Conclusions: Patients with thin endometrium have poor pregnancy outcomes. The clinical pregnancy rate, embryo implantation rate and live birth rate of embryo-transfer and blastocyst-transfer are similar in patients with thin endometrium. Compared thin endometrium and non-thin endometrium patients, the clinical pregnancy rate and live birth rate of blastocysts have more substantial decline than those of embryos. Improving the quality of embryo could improve the pregnancy outcome of patients with thin endometrium. Sildenafil and growth hormone could not improve pregnancy outcome in patients with thin endometrium.


Assuntos
Blastocisto , Implantação do Embrião , Transferência Embrionária/métodos , Endométrio/anatomia & histologia , Terapia de Reposição Hormonal , Resultado da Gravidez , Adulto , Criopreservação , Feminino , Humanos , Ciclo Menstrual , Gravidez , Taxa de Gravidez , Estudos Prospectivos
6.
Phys Rev Lett ; 115(8): 086601, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26340196

RESUMO

We address the controversy over the spin transport mechanism in Alq3 utilizing spin pumping in the Y3Fe5O12/Alq3/Pd system. An unusual angular dependence of the inverse spin Hall effect is found. It, however, disappears when the microwave magnetic field is fully in the sample plane, excluding the presence of the Hanle effect. Together with the quantitative temperature-dependent measurements, these results provide compelling evidence that the pure spin current transport in Alq3 is dominated by the exchange-mediated mechanism.

7.
Phys Rev Lett ; 110(16): 167201, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23679635

RESUMO

A Skyrmion crystal typically arises from helical spin structures induced by the Dzyaloshinskii-Moriya interaction. Experimentally its physical exploration has been impeded because it is a rarity and is found only within a narrow temperature and magnetic field range. We present a method for the assembly of a two-dimensional Skyrmion crystal based upon a combination of a perpendicularly magnetized film and nanopatterned arrays of magnetic vortices that are geometrically confined within nanodisks. The practical feasibility of the method is validated by micromagnetic simulations and computed Skyrmion number per unit cell. We also quantify a wide range in temperature and field strength over which the Skyrmion crystal can be stabilized without the need for any intrinsic Dzyaloshinskii-Moriya interactions, which otherwise is needed to underpin the arrangement as is the case in the very few known Skyrmion crystal cases. Thus, our suggested scheme involves a qualitative breakthrough that comes with a substantial quantitative advance.

8.
Science ; 265(5173): 796-9, 1994 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-8047885

RESUMO

The high-mobility group protein 14 (HMG-14) is a non-histone chromosomal protein that is preferentially associated with transcriptionally active chromatin. To assess the effect of HMG-14 on transcription by RNA polymerase II, in vivo-assembled chromatin with elevated amounts of HMG-14 was obtained. Here it is shown that HMG-14 enhanced transcription on chromatin templates but not on DNA templates. This protein stimulated the rate of elongation by RNA polymerase II but not the level of initiation of transcription. These findings suggest that the association of HMG-14 with nucleosomes is part of the cellular process involved in the generation of transcriptionally active chromatin.


Assuntos
Proteínas de Grupo de Alta Mobilidade/fisiologia , RNA Polimerase II/metabolismo , Transcrição Gênica/fisiologia , Cromatina/metabolismo , Células HeLa , Humanos , Cinética , Vírus 40 dos Símios/genética , Moldes Genéticos
9.
Zhonghua Shao Shang Za Zhi ; 35(6): 467-471, 2019 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-31280543

RESUMO

Metabolic disorder is one of the most obvious pathophysiological characteristics of patients with severe burn or trauma, which leads to high mortality of patients with severe burn or trauma. Metabonomics is a newly developed subject which provides new research concepts and ideas for studying the changes of metabolism in a disease condition. Based on the analysis of group indicators, metabonomic technique not only can systematically study the change rules of metabolites, which helps to further clarify the pathophysiological mechanism of burn or trauma, but also is helpful to find some significant biomarkers with important clinical value so as to provide new insight for the therapy of burn or trauma. This paper reviews the research progress of application of metabonomics in the treatment of severe burn or trauma in recent years.


Assuntos
Queimaduras/terapia , Metabolômica , Proteínas/uso terapêutico , Biomarcadores , Queimaduras/metabolismo , Humanos , Metabolômica/tendências , Proteínas/metabolismo
10.
Artigo em Chinês | MEDLINE | ID: mdl-30813701

RESUMO

Objective:To explore the clinical value of nasal endoscope combined with supporting laryngoscope surgery in the treatment of polyps of vocal cord. Method:Ninety-four patients with vocal cord polyps were randomly divided into the control group (47 cases) and the observation group (47 cases). The patients in the control group were treated with simply supporting laryngoscope surgery while the patients in the observation group were treated with nasal endoscope combined with supporting laryngoscope. The therapeutic effects, voice function changes before and after operation, complications and recurrence of the two groups were observed. Result:The total effective rate was 93.62% in the observation group, compared to 78.72% in the control group, the difference was statistically significant (P<0.05). The incidence of postoperative complications in the observation group was 8.51%, compared with 25.53% in the control group, the difference was statistically significant (P<0.05). Six months after operation, there was no recurrence in the observation group, but the recurrence rate in the control group was 4.26%. There was no significant difference between the two groups (P>0.05). 12 months after operation, the recurrence rate of the observation group was 2.13%, compared with 14.89% of the control group, the difference was statistically significant (P<0.05). Conclusion:Nasal endoscope combined with supporting laryngoscope for vocal cord polyps has a definite effect and can significantly improve the voice function of patients with high safety and low recurrence rate, which is worthy of promotion..


Assuntos
Doenças da Laringe , Laringoscopia , Pólipos , Prega Vocal , Humanos , Doenças da Laringe/cirurgia , Laringoscópios , Pólipos/cirurgia , Qualidade da Voz
11.
Oncogene ; 37(1): 18-27, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-28869597

RESUMO

Mice lacking genes involving in the DNA-damage response (DDR) are often tumor prone owing to genome instability caused by oncogenic challenges. Previous studies demonstrate that activating transcription factor 3 (ATF3), a common stress sensor, can activate the tumor suppressor p53 and regulate expression of p53 target genes upon DNA damage. However, whether ATF3 contributes to the maintenance of genome stability and tumor suppression remains unknown. Here we report that Atf3-deficient (Atf3-/-) mice developed spontaneous tumors, and died significantly earlier than wild-type (Atf3+/+) mice. Consistent with these results, Atf3-/- mouse embryonic fibroblasts (MEFs) had more aberrant chromosomes and micronuclei, and were genetically unstable. Whereas we demonstrated that ATF3 activated p53 and promoted its pro-apoptotic activity in mouse thymi and small intestines, the chromosomal instability caused by Atf3 deficiency was largely dependent on the regulation of p53 by ATF3. Interestingly, loss of Atf3 also promoted spontaneous tumorigenesis in Trp53+/- mice, but did not affect tumor formation in Trp53-/- mice. Our results thus provide the first genetic evidence linking ATF3 to the suppression of the early development of cancer, and underscore the importance of ATF3 in the maintenance of genome integrity.


Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Carcinogênese/genética , Predisposição Genética para Doença , Instabilidade Genômica , Neoplasias/genética , Fator 3 Ativador da Transcrição/genética , Animais , Apoptose/genética , Linhagem Celular Tumoral , Aberrações Cromossômicas , Dano ao DNA , Feminino , Fibroblastos , Genes Supressores de Tumor , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias/mortalidade , Neoplasias/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
Mol Cell Biol ; 17(10): 5843-55, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9315642

RESUMO

Histone H1 promotes the generation of a condensed, transcriptionally inactive, higher-order chromatin structure. Consequently, histone H1 activity must be antagonized in order to convert chromatin to a transcriptionally competent, more extended structure. Using simian virus 40 minichromosomes as a model system, we now demonstrate that the nonhistone chromosomal protein HMG-14, which is known to preferentially associate with active chromatin, completely alleviates histone H1-mediated inhibition of transcription by RNA polymerase II. HMG-14 also partially disrupts histone H1-dependent compaction of chromatin. Both the transcriptional enhancement and chromatin-unfolding activities of HMG-14 are mediated through its acidic, C-terminal region. Strikingly, transcriptional and structural activities of HMG-14 are maintained upon replacement of the C-terminal fragment by acidic regions from either GAL4 or HMG-2. These data support the model that the acidic C terminus of HMG-14 is involved in unfolding higher-order chromatin structure to facilitate transcriptional activation of mammalian genes.


Assuntos
Cromatina/metabolismo , Proteínas de Grupo de Alta Mobilidade/química , Histonas/metabolismo , Transcrição Gênica/fisiologia , Sequência de Aminoácidos , Células HeLa , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Grupo de Alta Mobilidade/fisiologia , Humanos , Modelos Genéticos , Dados de Sequência Molecular , RNA Polimerase II/metabolismo , RNA Viral/biossíntese , Proteínas Recombinantes de Fusão , Deleção de Sequência , Vírus 40 dos Símios/genética , Ativação Transcricional/fisiologia
13.
Oncogene ; 36(11): 1546-1558, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27617576

RESUMO

Epithelial-mesenchymal transition (EMT) is regarded as a crucial contributing factor to cancer progression. Diverse factors have been identified as potent EMT inducers in ovarian cancer. However, molecular mechanism sustaining EMT of ovarian cancer cells remains elusive. Here we show that the presence of SOS1/EPS8/ABI1 complex is critical for sustained EMT traits of ovarian cancer cells. Consistent with the role of SOS1/EPS8/ABI1 complex as a Rac1-specific guanine nucleotide exchange factor, depleting Rac1 results in the loss of most of mesenchymal traits in mesenchymal-like ovarian cancer cells, whereas expressing constitutively active Rac1 leads to EMT in epithelial-like ovarian cancer cells. With the aid of clinically tested inhibitors targeting various EMT-associated signaling pathways, we show that only combined treatment of mitogen-activated extracellular signal-regulated kinase 1/2 (MEK1/2) and Src inhibitors can abolish constitutively active Rac1-led EMT and mesenchymal traits displayed by mesenchymal-like ovarian cancer cells. Further experiments also reveal that EMT can be induced in epithelial-like ovarian cancer cells by co-expressing constitutively active MEK1 and Src rather than either alone. As the activities of Erk and Src are higher in ovarian cancer cells with constitutively active Rac1, we conclude that Rac1 sustains ovarian cancer cell EMT through simultaneous activation of MEK1/2 and Src signaling pathways. Importantly, we demonstrate that combined use of MEK1/2 and Src inhibitors effectively suppresses development of intraperitoneal xenografts and prolongs the survival of ovarian cancer-bearing mice. This study suggests that cocktail of MEK1/2 and Src inhibitors represents an effective therapeutic strategy against ovarian cancer progression.


Assuntos
Transição Epitelial-Mesenquimal , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 2/metabolismo , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP/metabolismo , Quinases da Família src/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Linhagem Celular Tumoral , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Feminino , Proteínas de Homeodomínio/metabolismo , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Proteínas Repressoras/metabolismo , Proteína SOS1/metabolismo , Fatores de Transcrição Twist/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Homeobox 2 de Ligação a E-box com Dedos de Zinco , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
15.
Sci Rep ; 6: 18615, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26733075

RESUMO

Utilizing epitaxial Co2Fe1-xMnxAl full-Heusler alloy films on GaAs (001), we address the controversy over the analysis for the split hysteresis loop which is commonly found in systems consisting of both uniaxial and fourfold anisotropies. Quantitative comparisons are carried out on the values of the twofold and fourfold anisotropy fields obtained with ferromagnetic resonance and vibrating sample magnetometer measurements. The most suitable model for describing the split hysteresis loop is identified. In combination with the component resolved magnetization measurements, these results provide compelling evidences that the switching is caused by the domain wall nucleation and movements with the switching fields centered at the point where the energy landscape shows equal minima for magnetization orienting near the easy axis and the field supported hard axis.

16.
Oncogene ; 35(27): 3555-64, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-26522727

RESUMO

Steroid sex hormones can induce prostate carcinogenesis, and are thought to contribute to the development of prostate cancer during aging. However, the mechanism for hormone-induced prostate carcinogenesis remains elusive. Here, we report that activating transcription factor 3 (ATF3)-a broad stress sensor-suppressed hormone-induced prostate carcinogenesis in mice. Although implantation of testosterone and estradiol (T+E2) pellets for 2 months in wild-type mice rarely induced prostatic intraepithelial neoplasia (PIN) in dorsal prostates (one out of eight mice), the loss of ATF3 led to the appearance of not only PIN but also invasive lesions in almost all examined animals. The enhanced carcinogenic effects of hormones on ATF3-deficient prostates did not appear to be caused by a change in estrogen signaling, but were more likely a consequence of elevated androgen signaling that stimulated differentiation of prostatic basal cells into transformation-preferable luminal cells. Indeed, we found that hormone-induced lesions in ATF3-knockout mice often contained cells with both basal and luminal characteristics, such as p63(+) cells (a basal-cell marker) showing luminal-like morphology, or cells double-stained with basal (CK5(+)) and luminal (CK8(+)) markers. Consistent with these findings, low ATF3 expression was found to be a poor prognostic marker for prostate cancer in a cohort of 245 patients. Our results thus support that ATF3 is a tumor suppressor in prostate cancer.


Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Carcinogênese/metabolismo , Células Epiteliais/metabolismo , Queratina-5/metabolismo , Queratina-8/metabolismo , Próstata/metabolismo , Fator 3 Ativador da Transcrição/genética , Animais , Western Blotting , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Linhagem Celular , Linhagem Celular Tumoral , Células Epiteliais/efeitos dos fármacos , Estradiol/toxicidade , Hormônios/toxicidade , Humanos , Imuno-Histoquímica , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Próstata/efeitos dos fármacos , Próstata/patologia , Neoplasia Prostática Intraepitelial/induzido quimicamente , Neoplasia Prostática Intraepitelial/genética , Neoplasia Prostática Intraepitelial/metabolismo , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Interferência de RNA , Testosterona/toxicidade
17.
Oncogene ; 34(38): 4975-84, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25531328

RESUMO

Activating transcription factor 3 (ATF3) responds to diverse cellular stresses, and regulates oncogenic activities (for example, proliferation, survival and migration) through direct transcriptional regulation or protein-protein interactions. Although aberrant ATF3 expression is frequently found in human cancers, the role of ATF3 in tumorigenesis is poorly understood. Here, we demonstrate that ATF3 suppresses the development of prostate cancer induced by knockout of the tumor suppressor Pten in mouse prostates. Whereas the oncogenic stress elicited by Pten loss induced ATF3 expression in prostate epithelium, we found that ATF3 deficiency increased cell proliferation and promoted cell survival, leading to early onset of mouse prostatic intraepithelial neoplasia and the progression of prostate lesions to invasive adenocarcinoma. Importantly, the loss of ATF3 promoted activation of the oncogenic AKT signaling evidenced by high levels of phosphorylated AKT and S6 proteins in ATF3-null prostate lesions. In line with these in vivo results, knockdown of ATF3 expression in human prostate cancer cells by single guided RNA-mediated targeting activated AKT and increased matrix metalloproteinase-9 expression. Our results thus link ATF3 to the AKT signaling, and suggest that ATF3 is a tumor suppressor for the major subset of prostate cancers harboring dysfunctional Pten.


Assuntos
Fator 3 Ativador da Transcrição/fisiologia , PTEN Fosfo-Hidrolase/fisiologia , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator 3 Ativador da Transcrição/genética , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Ativação Enzimática , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , PTEN Fosfo-Hidrolase/genética , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/metabolismo , Transdução de Sinais
18.
Sci Rep ; 5: 12092, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26160318

RESUMO

Low dimensional nanostructures have attracted attention due to their rich physical properties and potential applications. The essential factor for their functionality is their electronic properties, which can be modified by quantum confinement. Here the electronic states of Gd atom trapped in open Fe corrals on Ag(111) were studied via scanning tunneling spectroscopy. A single spectroscopic peak above the Fermi level is observed after Gd adatoms are trapped inside Fe corrals, while two peaks appear in empty corrals. The single peak position is close to the higher energy peak of the empty corrals. These findings, attributed to quantum confinement of the corrals and Gd structures trapped inside, are supported by tight-binding calculations. This demonstrates and provides insights into atom trapping in open corrals of various diameters, giving an alternative approach to modify the properties of nano-objects.


Assuntos
Gadolínio/química , Nanoestruturas/química , Ferro/química , Microscopia de Tunelamento/métodos , Nanotecnologia/métodos , Prata/química , Análise Espectral/métodos
19.
J Med Microbiol ; 31(2): 95-102, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2406449

RESUMO

C3H/HeNMTV mice were immunised intraperitoneally (i.p.) with lipopolysaccharide (LPS) or detoxified LPS (D-LPS) derived from Salmonella typhimurium strain SR-11. In both cases, effective protection was achieved against a challenge dose of greater than 2 x 10(2) LD50 of the same organism given by i.p. injection. However, by comparison with LPS, approximately 6- to 10-fold more of D-LPS by weight was needed to protect mice to an equivalent degree. Histopathological studies showed that the initial lesions in infected mice protected with either LPS or D-LPS were composed of self-limiting abscesses which transformed into granulomas as the animals recovered. It is suggested that D-LPS may be modified to become a highly effective, non-toxic salmonella vaccine.


Assuntos
Vacinas Bacterianas/imunologia , Lipopolissacarídeos/imunologia , Salmonelose Animal/prevenção & controle , Salmonella typhimurium/patogenicidade , Animais , Eletroforese em Gel de Poliacrilamida , Granuloma/patologia , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Salmonelose Animal/microbiologia , Salmonella typhimurium/imunologia , Virulência
20.
Zhongguo Zhong Yao Za Zhi ; 19(10): 598-600, 638, 1994 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-7873077

RESUMO

This paper deals with the extraction, determination and identification of the alkaloids in differently processed products of the seeds of Strychnos nux-vomica. The relationship between processing methods and toxicitys is discussed according to the comparison of acute toxicity.


Assuntos
Alcaloides/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Alcaloides/toxicidade , Animais , Medicamentos de Ervas Chinesas/toxicidade , Feminino , Temperatura Alta , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estricnina/isolamento & purificação , Tecnologia Farmacêutica
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