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Spider pulsars are neutron stars that have a companion star in a close orbit. The companion star sheds material to the neutron star, spinning it up to millisecond rotation periods, while the orbit shortens to hours. The companion is eventually ablated and destroyed by the pulsar wind and radiation1,2. Spider pulsars are key for studying the evolutionary link between accreting X-ray pulsars and isolated millisecond pulsars, pulsar irradiation effects and the birth of massive neutron stars3-6. Black widow pulsars in extremely compact orbits (as short as 62 minutes7) have companions with masses much smaller than 0.1 Mâ. They may have evolved from redback pulsars with companion masses of about 0.1-0.4 Mâ and orbital periods of less than 1 day8. If this is true, then there should be a population of millisecond pulsars with moderate-mass companions and very short orbital periods9, but, hitherto, no such system was known. Here we report radio observations of the binary millisecond pulsar PSR J1953+1844 (M71E) that show it to have an orbital period of 53.3 minutes and a companion with a mass of around 0.07 Mâ. It is a faint X-ray source and located 2.5 arcminutes from the centre of the globular cluster M71.
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Fast radio bursts (FRBs) are millisecond-duration radio transients1,2 of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star magnetospheres3-5 or relativistic shocks far from the central energy source6-8. Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters9,10 or variable polarization angles in some other apparently one-off events11,12. Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks.
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Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.
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Objective: To analyze the gender differences of genetic etiology in the incidence of major depression disorder among Han freshmen. Methods: A 1-year follow-up survey was carried out among 8 079 Han freshmen from Jining, Rizhao and Weifang without lifetime major depressive disorder (MDD) at baseline (April to October 2018) and 4 828 venous blood samples were also collected. After extracting DNA, Sequenom Mass Array time-of-flight mass spectrometry biochip technology was used to detect the genotypes of 17 single nucleotide polymorphisms (SNPs) MDD-related loci. Logistic regression was used for univariate analysis. Generalized multifactor dimension reduction was used to analyze gene-gene interactions. Composite International Diagnostic Interview (CIDI) 3.0 was used for MDD diagnosis. Results: The 1-year incidence of MDD among Han freshmen was 2.23% (95%CI: 1.91%-2.60%) and the gender difference of incidence between males (1.97%, 95%CI: 1.52%-2.56%) and females (2.39%, 95%CI: 1.98%-2.90%) was not statistically significant (P>0.05). AG genotype of rs768705 (nearby gene: TMEM161B) was a risk factor for MDD (OR=1.98, 95%CI: 1.24-2.83). The TC genotype of rs17727765 (nearby gene: CRYBA1) was only a risk factor for MDD in males (OR=9.61, 95%CI: 2.04-45.30). An 8-loci interaction model (PMFBP1, OLFM4, LHPP, ENOX1, TMEM161B, SPPL3, FBXL4 and L3MBTL2) could predict MDD in women with an accuracy rate of 60.05%. No effective prediction model was found for MDD in men. Conclusions: There might be gender differences in the genetic etiology of MDD. Further researches on the genetic causes of MDD in men should be explored.
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Transtorno Depressivo Maior , Povo Asiático , Estudos de Casos e Controles , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/genética , Feminino , Predisposição Genética para Doença , Humanos , Incidência , Masculino , Polimorfismo de Nucleotídeo Único , Fatores SexuaisRESUMO
PURPOSE: It has been reported that proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors can significantly reduce lipoprotein(a) [Lp(a)], and the mechanism for Lp(a) reduction remains unclear. Recently an interesting clinical research with a small sample showed a positive correlation between plasma PCSK9 and Lp(a) levels in diabetes. Here we aimed to use a relatively large sample to investigate whether such an association exists in Han Chinese. METHODS: A total of 783 inpatients were consecutively enrolled and composed of 172 patients with type 2 diabetes mellitus (T2DM) and 611 non-T2DM subjects. Plasma PCSK9 level was measured by ELISA, and its association with Lp(a) was assayed by Spearman's correlation and multiple regression. Clinical and biochemical parameters were determined in all subjects studied. RESULTS: No significant differences in PCSK9 and Lp(a) levels were found between T2DM and non-T2DM patients. PCSK9 level was not related to Lp(a) level either in T2DM or non-T2DM group in bivariate correlation and multiple linear regression analysis. Additionally, no association between the levels of PCSK9 and Lp(a) was found in well, poorly controlled T2DM patients or in T2DM patients with or without coronary artery disease (CAD). Besides, no difference was found among the PCSK9 values across tertiles of Lp(a) level. CONCLUSION: We found no association of plasma PCSK9 levels with Lp(a) level in Han Chinese with or without T2DM, suggesting that Lp(a) reduction by PCSK9 inhibitors may not be achieved simply through PCSK9 pathway at least in Chinese.
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Biomarcadores/sangue , Diabetes Mellitus Tipo 2/sangue , Lipoproteína(a)/sangue , Pró-Proteína Convertase 9/sangue , Estudos de Casos e Controles , China/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
Human activities have resulted in arsenic (As) and heavy metals accumulation in paddy soils in China. Phytoremediation has been suggested as an effective and low-cost method to clean up contaminated soils. A combined soil-sand pot experiment was conducted to investigate the influence of red mud (RM) supply on iron plaque formation and As and heavy metal accumulation in two wetland plant species (Cyperus alternifolius Rottb., Echinodorus amazonicus Rataj), using As and heavy metals polluted paddy soil combined with three rates of RM application (0, 2%, 5%). The results showed that RM supply significantly decreased As and heavy metals accumulation in shoots of the two plants due to the decrease of As and heavy metal availability and the enhancement of the formation of iron plaque on the root surface and in the rhizosphere. Both wetland plants supplied with RM tended to have more Fe plaque, higher As and heavy metals on roots and in their rhizospheres, and were more tolerant of As and heavy metal toxicity. The results suggest that RM-induced enhancement of the formation of iron plaque on the root surface and in the rhizosphere of wetland plants may be significant for remediation of soils contaminated with As and heavy metals.
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Alismataceae/metabolismo , Arsênio/metabolismo , Cyperus/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , China , Raízes de Plantas/metabolismo , Áreas AlagadasRESUMO
OBJECTIVE: With the development of modern skull base minimally invasive technology mature and neural radio surgery techniques, it is necessary to re-examine the therapeutic strategy for the treatment of petroclival meningiomas. To sum up the operative experience and methods in microsurgical resection of petroclival meningiomas by the combining trans-subtemporal and suboccipital retrosigmoid keyhole approach. To explore the minimally invasive operation approach of petroclival meningiomas, to raise the removal degree and to improve the postoperative result using this approach. METHODS: The clinical data of the consecutive 21 patients with the petroclival meningiomas were reviewed retrospectively. The method, degree of tumor resection,techniques of the combining keyhole approach, Karnofsky performance score (KPS) before and after operation were also analyzed. The neuronavigation guided operation was performed in 9 cases, and 12 cases were operated in the neuroelectrophysiological monitoring. RESULTS: Total excision of the tumor resection (Simpson, I-II levels) was conducted in 18 cases (85.7%, 18/21), and 3 patients underwent close resection (Simpson III level, 14.3%, 3/21). Postoperative three-dimensional CT showed good lock bone flap restoration; Postoperative pathology confirmed meningioma. Postoperative cranial nerve dysfunction or new original nerve dysfunction were aggravated in 5 cases (23.8%) , including transient trochlear nerve (3 cases), abducent nerve (1 case), and the motor branch of trigeminal nerve paralysis (1 case). Abducent nerve paralysis (1 case) appeared, with hearing impairment. After the 3-month follow-up, 11 cases had the same KPS aspreoperation, 7 cases improved, and 3 cases not improved. The KPS score was 77.14±23.12 on average, and there was no statistically significant difference compared with that before operation (P>0.05). The postoperative follow-up for half a year showed fluent speaking and writing in 19 cases (KPS 70 or higher), and general recovery in 2 cases (KPS<70). The postoperative follow-up for 3-29 months showed no tumor recurrence or progress. CONCLUSION: The combining trans-subtemporal and suboccipital retrosigmoid keyhole approach is simple, safe, and minimally invasive, and an ideal operation approach of petroclival meningioma. To master the operation skills and the intraoperative matters needing attention in the operation, is favorable to improve the resection rate and curative effect.
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Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Procedimentos Neurocirúrgicos , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos , Recidiva Local de Neoplasia , Período Pós-Operatório , Estudos Retrospectivos , Neoplasias da Base do Crânio , Resultado do TratamentoRESUMO
OBJECTIVE: With the development of modern skull base minimally invasive technology mature and neural radio surgery techniques, it is necessary to re-examine the therapeutic strategy for the treatment of petroclival meningiomas. To sum up the operative experience and methods in microsurgical resection of petroclival meningiomas by the combining trans-subtemporal and suboccipital retrosigmoid keyhole approach. To explore the minimally invasive operation approach of petroclival meningiomas, to raise the removal degree and to improve the postoperative result using this approach. METHODS: The clinical data of the consecutive 21 patients with the petroclival meningiomas were reviewed retrospectively. The method, degree of tumor resection,techniques of the combining keyhole approach, Karnofsky performance score (KPS) before and after operation were also analyzed. The neuronavigation guided operation was performed in 9 cases, and 12 cases were operated in the neuroelectrophysiological monitoring. RESULTS: Total excision of the tumor resection (Simpson, I-II levels) was conducted in 18 cases (85.7%, 18/21), and 3 patients underwent close resection (Simpson III level, 14.3%, 3/21). Postoperative three-dimensional CT showed good lock bone flap restoration; Postoperative pathology confirmed meningioma. Postoperative cranial nerve dysfunction or new original nerve dysfunction were aggravated in 5 cases (23.8%) , including transient trochlear nerve (3 cases), abducent nerve (1 case), and the motor branch of trigeminal nerve paralysis (1 case). Abducent nerve paralysis (1 case) appeared, with hearing impairment. After the 3-month follow-up, 11 cases had the same KPS aspreoperation, 7 cases improved, and 3 cases not improved. The KPS score was 77.14±23.12 on average, and there was no statistically significant difference compared with that before operation (P>0.05). The postoperative follow-up for half a year showed fluent speaking and writing in 19 cases (KPS 70 or higher), and general recovery in 2 cases (KPS<70). The postoperative follow-up for 3-29 months showed no tumor recurrence or progress. CONCLUSION: The combining trans-subtemporal and suboccipital retrosigmoid keyhole approach is simple, safe, and minimally invasive, and an ideal operation approach of petroclival meningioma. To master the operation skills and the intraoperative matters needing attention in the operation, is favorable to improve the resection rate and curative effect.
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BACKGROUND: Interactions between the thalamus and the cortex play an important role in consciousness. The thalamus as a homogenous structure is less strongly connected with the default mode network (DMN) in patients with disorders of consciousness (DOC), but the roles of specific thalamic nuclei are not clear. The purpose of this study was to investigate the functional connectivity between individual thalamic nuclei and the DMN in DOC patients. METHODS: Nine DOC patients and nine age-matched healthy controls were scanned with functional magnetic resonance imaging (fMRI) at resting state. Data-driven independent component analysis and hypothesis-driven region of interest-based correlation analysis were performed. RESULTS: In comparison with healthy controls, DOC patients had significantly decreased functional connectivity between the mediodorsal thalamus and brain areas within the DMN, including the medial prefrontal cortex and posterior cingulate cortex/precuneus. Patients and controls did not show significant differences in functional connectivity in other thalamic nuclei. CONCLUSION: Our results suggest that functional connections between the mediodorsal thalamus and the DMN may play important roles in the pathogenesis of DOC.
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Córtex Cerebral/patologia , Transtornos da Consciência/patologia , Tálamo/patologia , Adulto , Córtex Cerebral/fisiopatologia , Transtornos da Consciência/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tálamo/fisiopatologiaRESUMO
BACKGROUND AND AIMS: Proprotein convertase subtilisin-kexin type 9 (PCSK9) is a novel regulator of low-density lipoprotein (LDL) metabolism. Recently, small dense LDL (sdLDL) particles have been suggested to be a very atherogenic subspecies of LDL. To date, the association of sdLDL with PCSK9 is still unclear. The aim of the present study is to determine the association of sdLDL, as assayed by sdLDL-cholesterol (sdLDL-C), with PCSK9 in a cohort of subjects undergoing coronary angiography. METHODS AND RESULTS: Four hundred and ninety consecutive subjects were enrolled and classified into stable coronary artery disease (CAD) and non-CAD group. LDL separation was performed by Lipoprint System: 7 LDL subfractions were obtained and LDL score (% sdLDL) was calculated. The plasma PCSK9 levels were measured by ELISA. The data indicated that PCSK9 levels were significantly increased by sdLDL-C quartiles (p = 0.028). In age- and sex-adjusted analysis plasma sdLDL-C was positively correlated with PCSK9 levels (r = 0.157, p < 0.01). To rule out the confounding effect of dyslipidemia, we performed the analysis in subjects with and without dyslipidemia separately. Interestingly, the positive correlation of sdLDL-C with PCSK9 was only significant in patients with dyslipidemia and stable CAD (r = 0.177, p < 0.01). In a model adjusting for traditional risk factors including dyslipidemia, PCSK9 was an independent predictor of high sdLDL-C in CAD group (OR = 12.919, 95% CI 1.427-116.952) but not in non-CAD group. CONCLUSION: This study firstly demonstrated that plasma sdLDL-C was positively related to PCSK9 in patients with stable CAD, suggesting an interaction between sdLDL-C and PCSK9 in atherosclerotic coronary disease.
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LDL-Colesterol/sangue , Angiografia Coronária/métodos , Doença da Artéria Coronariana/sangue , Pró-Proteína Convertases/sangue , Serina Endopeptidases/sangue , Idoso , Aterosclerose/sangue , Índice de Massa Corporal , Estudos Transversais , Dislipidemias/sangue , Feminino , Homeostase , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Tamanho da Partícula , Pró-Proteína Convertase 9 , Fatores de RiscoRESUMO
OBJECTIVE: To investigate the association of resistin with proprotein convertase subtilisin-kexin type 9 (PCSK9) levels, another novel regulator of atherosclerosis, in the condition of coronary artery disease (CAD). RESEARCH DESIGN AND METHODS: We prospectively enrolled a total of 356 consecutive stable CAD patients who were not treated with lipid-lowering drugs in the present study. The baseline clinical characteristics were collected. Plasma PCSK9 and resistin levels were determined by ELISA. The relationship between plasma PCSK9 and resistin levels was investigated. RESULTS: Overall, plasma resistin exhibited a positive nonparametric correlation with PCSK9 levels (r = 0.123, p = 0.02). When the patients were classified into groups based on body mass index (BMI), the resistin correlated significantly to the PCSK9 levels in patients with BMI < 25 kg/m(2) (r = 0.162, p = 0.026) but not in patients with BMI ≥ 25 kg/m(2) (r = 0.087, p = 0.205). Multivariate regression analysis corroborated the relation between the PCSK9 and an elevated resistin level in patients with BMI < 25 kg/m(2) independently of traditional parameters including age, sex, BMI, smoking, family history of CAD, systolic blood pressure, glucose, low density lipoprotein cholesterol, white blood cell, neutrophil to lymphocyte ratio, and high-sensitive C-reactive protein. CONCLUSIONS: Plasma resistin was positively related to PCSK9 levels in CAD patients with normal weight, suggesting that the circulating resistin might represent a link with PCSK9 level variations in CAD progression of normal body weight.
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Índice de Massa Corporal , Doença da Artéria Coronariana/sangue , Pró-Proteína Convertases/sangue , Resistina/sangue , Serina Endopeptidases/sangue , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pró-Proteína Convertase 9RESUMO
Antisense long non-coding RNAs (AS lncRNAs) play important roles in refined regulation of animal gene expression. However, their functions and molecular mechanisms for domestic animal adipogenesis are largely unknown. Here, we found a novel AS lncRNA transcribed from the porcine PU.1 gene (also known as SPI1) by strand-specific RT-PCR. Results showed that PU.1 AS lncRNA was expressed and generally lower than the level of PU.1 mRNA in porcine subcutaneous adipose, heart, liver, spleen, lympha, skeletal muscle and kidney tissues. We further found that the levels of PU.1 mRNA and PU.1 protein were significantly lower in subcutaneous and intermuscular adipose than in mesenteric and greater omentum adipose, whereas the levels of PU.1 AS lncRNA showed no difference in porcine adipose tissues from four different parts of the body. During porcine adipogenesis, levels of PU.1 mRNA increased at day 2 and then gradually decreased. Meanwhile, PU.1 AS lncRNA exhibited an expression trend similar to PU.1 mRNA but sharply decreased after day 2. Interestingly, PU.1 protein level rose during differentiation. In addition, at day 6 after differentiation, knockdown of endogenous PU.1 promoted adipogenesis, whereas knockdown of endogenous PU.1 AS lncRNA had the opposite effect. Moreover, peroxisome proliferator-activated receptor gamma (PPARG) and fatty acid synthase (FASN) were significantly upregulated in the PU.1 shRNA treatment group (P < 0.05), whereas they were downregulated in the PU.1 AS shRNA treatment group (P < 0.05). Adipose triglyceride lipase [ATGL; also known as patatin-like phospholipase domain containing 2 (PNPLA2)] and hormone-sensitive lipase [HSL; also known as lipase, hormone-sensitive (LIPE)] contrasted with PPARG and FASN. Finally, the PU.1 mRNA/PU.1 AS lncRNA duplex was detected by an endogenous ribonuclease protection assay combined with RT-PCR. Based on the above results, we suggest that PU.1 AS lncRNA (vs. its mRNA translation) promotes adipogenesis through the formation of a sense-antisense RNA duplex with PU.1 mRNA.
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Adipócitos/citologia , Adipogenia/genética , Biossíntese de Proteínas , Proteínas Proto-Oncogênicas/genética , RNA Antissenso/genética , RNA Longo não Codificante/genética , Transativadores/genética , Animais , Diferenciação Celular , Células Cultivadas , Técnicas de Silenciamento de Genes , SuínosRESUMO
We aimed to investigate the influence of lentiviral-mediated Bcl-2 overexpression in cerebral tissues of rats with acute cerebral infarction. Forty-five rats were randomly divided into sham, model, and treatment groups. The sham and model groups were administered a control lentiviral vector via the intracranial arteries 10 days before surgery, while the treatment group received lentivirus encoding a Bcl-2 overexpression vector. We induced cerebral artery infarction using a suture-occlusion method and analyzed the cerebral expression levels of apoptosis-related genes (caspase-3, Bax), total cerebral apoptosis, range of cerebral tissue infarction, and changes in nerve cell function after 72 h. The Bcl-2-encoding lentivirus was well expressed in rat cerebral tissues. The treatment group had significantly higher expression levels of Bcl-2 than the other two groups. After cerebral infarction, the model group had significantly increased expression levels of caspase-3 and Bax protein in cerebral tissues than the sham (P < 0.05). Expression of these apoptosis-related proteins in the treatment group was obviously lower than that in the model group (P < 0.05), but significantly higher than in the sham group (P < 0.05). Compared to sham, neuronal apoptosis levels and infarction range of cerebral tissues was increased in the model and treatment groups; however, these values in the treatment group were significantly lower than that in the model group (P < 0.05). Importantly, the treatment group had significantly decreased neurological impairment scores (P < 0.05). In conclusion, Bcl-2 over-expression can decrease neuronal apoptosis in rat cerebral tissue, and thus is neuroprotective after cerebral ischemia.
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Infarto Cerebral/metabolismo , Infarto Cerebral/patologia , Neurônios/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Doença Aguda , Animais , Apoptose , Encéfalo/metabolismo , Encéfalo/patologia , Caspase 3/metabolismo , Infarto Cerebral/fisiopatologia , Neurônios/patologia , Ratos Sprague-Dawley , Proteína X Associada a bcl-2/metabolismoRESUMO
Results of a theoretical study on non-Markov response for femtosecond laser-driven coherent ring currents in chiral aromatic molecules embedded in a condensed phase are presented. Coherent ring currents are generated by coherent excitation of a pair of quasi-degenerated π-electronic excited states. The coherent electronic dynamical behaviors are strongly influenced by interactions between the electronic system and phonon bath in a condensed phase. Here, the bath correlation time is not instantaneous but should be taken to be a finite time in ultrashort time-resolved experiments. In such a case, Markov approximation breaks down. A hierarchical master equation approach for an improved semiclassical Drude dissipation model was adopted to examine the non-Markov effects on ultrafast coherent electronic ring currents of (P)-2,2'-biphenol in a condensed phase. Time evolution of the coherent ring current derived in the hierarchical master equation approach was calculated and compared with those in the Drude model in the Markov approximation and in the static limit. The results show how non-Markovian behaviors in quantum beat signals of ring currents depend on the Drude bath damping constant. Effects of temperatures on ultrafast coherent electronic ring currents are also clarified.
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AIMS: To isolate an alkaliphilic bacterium and to investigate its ability of extracellular reduction. METHODS AND RESULTS: An alkaliphilic and halotolerant humus-reducing anaerobe, Bacillus pseudofirmus MC02, was successfully isolated from a pH 10·0 microbial fuel cell. To examine its ability of extracellular reduction, AQDS (anthraquinone-2, 6-disulfonae), humic acids (HA) and Fe(III) oxides were chosen as representative electron acceptors. All the experiments were conducted in a pH 9·5 carbonate buffer. The results are as follows: (i) Sucrose, lactate, glucose and glycerol were the favourable electron donors for AQDS reduction by the strain MC02; (ii) The strain had the ability of reducing HA in the presence of sucrose; (iii) It could effectively reduce Fe(III) oxides coupled with sucrose fermentation when AQDS was added as electron shuttle and its Fe(III) reducing capacity ranked as: lepidocrocite (γ-FeOOH) > goethite (α-FeOOH) > haematite(α-Fe(2) O(3) ); (iv) The strain could decolourize azo dye Orange I. CONCLUSIONS: Bacillus pseudofirmus MC02 was capable of extracellular reduction in AQDS, HA and Fe(III) oxides, and it can be used for decolourizing azo dye (Orange I) in alkaline conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of an alkaliphlic strain of B. pseudofirmus capable of extracellular reduction in AQDS, HA, Fe(III) oxides and decolourization of Orange I. This study could provide valuable information on alkaline biotransformation in the printing and dyeing wastewater and saline-alkali soil.
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Bacillus/isolamento & purificação , Bacillus/metabolismo , Microbiologia do Solo , Antraquinonas/metabolismo , Bacillus/classificação , Bactérias Anaeróbias/metabolismo , Biodegradação Ambiental , Compostos Férricos/metabolismo , Substâncias Húmicas , Oxirredução , FilogeniaRESUMO
Cyclic nucleotides are second messengers that are essential in vision, muscle contraction, neurotransmission, exocytosis, cell growth, and differentiation. These molecules are degraded by a family of enzymes known as phosphodiesterases, which serve a critical function by regulating the intracellular concentration of cyclic nucleotides. We have determined the three-dimensional structure of the catalytic domain of phosphodiesterase 4B2B to 1.77 angstrom resolution. The active site has been identified and contains a cluster of two metal atoms. The structure suggests the mechanism of action and basis for specificity and will provide a framework for structure-assisted drug design for members of the phosphodiesterase family.
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3',5'-AMP Cíclico Fosfodiesterases/química , 3',5'-AMP Cíclico Fosfodiesterases/metabolismo , AMP Cíclico/metabolismo , Sítios de Ligação , Domínio Catalítico , Cristalização , Cristalografia por Raios X , AMP Cíclico/química , GMP Cíclico/química , GMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Ligação de Hidrogênio , Hidrólise , Metais/metabolismo , Modelos Moleculares , Conformação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Especificidade por SubstratoRESUMO
OBJECTIVES: To investigate the current prevalence of anemia among pregnant women in different areas of China and the association with birth weight and educational level. METHODS: A total of 6,413 women aged 24-37 in the third trimester of pregnancy from five areas were randomly selected from all gravidas who gave birth in the hospitals from 1999 to 2003. Blood hemoglobin concentration (Hb) was measured by the cyanomethemoglobin method; Hb <110 g/l was considered as anemia. RESULTS: The overall prevalence of anemia was 58.6%, ranging from 48.1 to 70.5% in the five areas. There was a significant difference in the prevalence of anemia between women who have mental jobs and those who have physical jobs (52.3 vs. 61.1%, p < 0.01). The prevalence of anemia depended on the level of education: with 52.9, 62.4 and 66.5%, for college, secondary school and primary education, respectively, and the difference was statistically significant (p = 0.005). Results showed that higher birth weight was associated with Hb concentrations ranging from 90 to 140 g/l, whereas lower birth weight occurred below 80 g/l and above 140 g/l Hb. CONCLUSIONS: The prevalence of anemia in Chinese pregnant women was high both in rural areas and towns. Area of residence, education level and type of job influenced the prevalence of anemia. Low maternal Hb concentrations influenced birth weight.
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Anemia/epidemiologia , Peso ao Nascer , Complicações Hematológicas na Gravidez/epidemiologia , Adulto , China/epidemiologia , Estudos Transversais , Escolaridade , Feminino , Humanos , Recém-Nascido , Gravidez , Terceiro Trimestre da Gravidez , Prevalência , População Rural , População Urbana , Adulto JovemRESUMO
We have developed a portable, handheld, integrated, dynamic breast imaging system that integrates a near infrared tissue oximeter, clinical ultrasound, and two pressure sensors for noninvasive detection of pressure-induced structural and functional dynamics of suspicious breast lesions. A series of benchtop tests were conducted to validate multiple performance characteristics of the integrated dynamic near infrared/ultrasound breast imaging system (idNIRUS), including the reconstruction of the absorptive heterogeneities and the generation of the dynamic compression stimuli. In absorptive heterogeneity testing, we reconstructed the absorption coefficients of transparent polypropylene tubing circulated with a skim milk-India ink mixture and embedded in a gel wax tissue simulating phantom. High linear correlations (R(2) greater than 0.989) were observed between the reconstructed and the measured absorption coefficients of the embedded tubing. In dynamic compression testing, five volunteer operators generated ten successive compression sessions by compressing the idNIRUS imager on a breast self examination wearable model following the computer simulated pressure profile. The manually generated pressure profiles demonstrated an accuracy of 95.7% and operator-dependent variation of less than 5%. The results of the current benchtop tests will help to optimize the most appropriate testing conditions for our future planned clinical trial.
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Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Mama/patologia , Algoritmos , Simulação por Computador , Computadores , Computadores de Mão , Diagnóstico por Imagem/instrumentação , Diagnóstico por Imagem/métodos , Detecção Precoce de Câncer , Desenho de Equipamento , Feminino , Humanos , Oncologia/métodos , Pressão , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Ultrassonografia/instrumentação , Ultrassonografia/métodosRESUMO
3JH alpha,H beta and 3JN,H beta coupling constants were measured for isotopically labeled FKBP when bound to the immunosuppressant, ascomycin, using a 1H-coupled 3D HCCH-TOCSY and 15N-coupled 3D HSQC-TOCSY experiment, respectively. From an analysis of these two sets of coupling constants, stereospecific beta-proton assignments and chi 1 rotamers for FKBP have been obtained. All of the chi 1 rotamers were consistent with the chi 1 angles measured in the X-ray crystal structure of the FKBP/FK506 complex, suggesting that the structures of the two complexes are similar.
Assuntos
Proteínas de Transporte/metabolismo , Tacrolimo/análogos & derivados , Tacrolimo/metabolismo , Sequência de Aminoácidos , Proteínas de Transporte/química , Humanos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Prótons , Proteínas Recombinantes/metabolismo , Proteínas de Ligação a Tacrolimo , Difração de Raios XRESUMO
Two multi-dimensional heteronuclear NMR experiments are described for assigning the resonances in uniformly 15N- and 13C-labeled proteins. In one experiment (HCNH-TOCSY), the amide nitrogen and proton are correlated to the side-chain protons and carbons of the same and preceding residue. In a second triple resonance experiment (HC(CO)NH-TOCSY), the amide nitrogen and proton of one residue is correlated exclusively with the side-chain proton and carbon resonances of the preceding residue by transferring magnetization through the intervening carbonyl. The utility of these two experiments for making sequential resonance assignments in proteins is illustrated for [U-15N,13C]FKBP (107 residues) complexed to the immunosuppressant, ascomycin.