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1.
Appl Opt ; 63(9): 2121-2131, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38568563

RESUMEN

An integrated path differential absorption (IPDA) lidar can accurately measure regional C O 2 weighted column average concentrations (X C O 2), which are crucial for understanding the carbon cycle in climate change studies. To verify the performance and data inversion methods of space-borne IPDA lidar, in July 2021, we conducted an airborne lidar validation experiment in Dunhuang, Gansu Province, China. An aircraft was equipped with a lidar system developed to measure X C O 2 and an in situ greenhouse gas analyzer (GGA). To minimize measurement errors, energy monitoring was optimized. The system bias error of the DAOD was determined by changing the laser output mode from the off/on to the on/on mode. The X C O 2 inversion results obtained through comparing the schemes of averaging signals before "log (logarithm)" and averaging after "log" indicate that the former performs better. The IPDA lidar measured X C O 2 over the validation site at 405.57 ppm, and both the IPDA lidar and GGA measured sudden changes in the C O 2 concentration. The assimilation data showed a similar trend according to the altitude to the data measured by the in situ instrument. A comparison of the mean X C O 2 derived from the GGA results and assimilation data with the IPDA lidar measurements showed biases of 0.80 and 1.12 ppm, respectively.

2.
Nanotechnology ; 34(23)2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36857761

RESUMEN

An ultra-thin overcoating of zirconium oxide (ZrO2) film on CuO-ZnO-Al2O3(CZA) catalysts by atomic layer deposition (ALD) was proved to enhance the catalytic performance of CZA/HZSM-5 (H form of Zeolite Socony Mobil-5) bifunctional catalysts for hydrogenation of CO2to dimethyl ether (DME). Under optimal reaction conditions (i.e. 240 °C and 2.8 MPa), the yield of product DME increased from 17.22% for the bare CZA/HZSM-5 catalysts, to 18.40% for the CZA catalyst after 5 cycles of ZrO2ALD with HZSM-5 catalyst. All the catalysts modified by ZrO2ALD displayed significantly improved catalytic stability of hydrogenation of CO2to DME reaction, compared to that of CZA/HZSM-5 bifunctional catalysts. The loss of DME yield in 100 h of reaction was greatly mitigated from 6.20% (loss of absolute value) to 3.01% for the CZA catalyst with 20 cycles of ZrO2ALD overcoating. Characterizations including hydrogen temperature programmed reduction, x-ray powder diffraction, and x-ray photoelectron spectroscopy revealed that there was strong interaction between Cu active centers and ZrO2.

3.
BMC Pregnancy Childbirth ; 23(1): 631, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37658306

RESUMEN

BACKGROUND: Preeclampsia complicated with hypofibrinogenemia is a rare disorder. We report two cases of severe preeclampsia complicated with hypofibrinogenemia followed by postpartum haemorrhage (PPH). CASE: Two women diagnosed as preeclampsia and hypofibrinogenemia developed severe PPH after undergoing Cesarean sections. Besides supplement with fibrinogen concentrate and supportive treatment, the second patient got administration of heparin after delivery and bleeding was stopped. The haemorrhage in case 1 didn't disappear until an hysterectomy. The two patients both recovered and were discharged soon. CONCLUSIONS: Severe preeclampsia patients with hypofibrinogenemia could suffer PPH. It's necessary to detect and master coagulation function. Heparin could be considered to balance hypercoagulation and hypocoagulation to avoid catastrophic haemorrhage and hysterectomy.


Asunto(s)
Afibrinogenemia , Hemorragia Posparto , Preeclampsia , Embarazo , Humanos , Femenino , Afibrinogenemia/complicaciones , Fibrinógeno/uso terapéutico , Hemorragia Posparto/etiología , Hemorragia Posparto/terapia , Heparina
4.
BMC Pregnancy Childbirth ; 23(1): 855, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38087253

RESUMEN

BACKGROUND: Several studies on pregnancy complications of poor ovarian response (POR) patients did not draw a consistent conclusion. The POSEIDON criteria introduces the concept of "low prognosis" and divides POR patients into four groups based on age, AFC and AMH for individualized management. We analyzed low-prognosis population and patients with regular ovarian response, compared maternal and neonatal complications and discussed the relevant risk factors. METHODS: A retrospective cohort study was conducted of females who achieved a singleton clinical pregnancy after IVF / ICSI-fresh embryo transfer in a single center from January 2014 to March 2019. Participants with low prognosis, as defined by the POSEIDON criteria, were enrolled in the study groups. The controls were defined as AFC ≥ five and number of retrieved oocytes > nine. Maternal and neonatal complications were compared among those groups. RESULTS: There were 2554 cycles in POSEIDON group 1, 971 in POSEIDON group 2, 141 in POSEIDON group 3, 142 in POSEIDON group 4, and 3820 in Control. Univariate analysis roughly showed that Groups 2 and 4 had an increased tendency of pregnancy complications. Multi-variable generalized estimating equations (GEE) analysis showed that the risks of GDM, total pregnancy loss, and first-trimester pregnancy loss in Groups 2 and 4 were significantly higher than in Control. The risk of hypertensive disorders of pregnancy (HDP) in Groups 2 and 3 increased, and Group 4 had an increased tendency without statistical significance. After classification by age, GEE analysis showed no significant difference in risks of all complications among groups ≥ 35 years. In patients < 35 years, the risk of HDP in POSEIDON group 3 was significantly higher than in controls (< 35 years), and there was no significant increase in the risk of other complications. CONCLUSION: Compared to patients with regular ovarian response, low-prognosis population have increased tendency of maternal and neonatal complications. In low-prognosis patients, advanced age (≥ 35 years) might be the predominant risk factor for pregnancy complications. In those < 35 years, poor ovarian reserve could contribute to HDP.


Asunto(s)
Aborto Espontáneo , Fertilización In Vitro , Embarazo , Recién Nacido , Humanos , Femenino , Adulto , Fertilización In Vitro/efectos adversos , Inyecciones de Esperma Intracitoplasmáticas/efectos adversos , Estudios Retrospectivos , Tasa de Natalidad , Inducción de la Ovulación , Transferencia de Embrión/efectos adversos , Pronóstico , Índice de Embarazo
5.
Urol Int ; 107(7): 747-750, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37321190

RESUMEN

Accessory spleen (AS) refers to single or multiple splenic tissues which appear outside the relative normal spleen position results from embryonic dysplasia similar in structure and function to the spleen. AS is frequently observed in the splenic hilus and or adjacent to the tail of pancreas, and only a few cases occurred in the pelvic cavity. We present an extremely rare AS case in urachus, which was initially considered as an urachal neoplasm revealed on CT images with big mass. However, the postoperative pathology confirmed it was an AS that had not been reported at urachal before. Urachal AS can be misdiagnosed as a tumor, so it is vital to make an accurate imaging preoperative diagnosis to avoid unnecessary biopsy and surgery.


Asunto(s)
Uraco , Humanos , Uraco/diagnóstico por imagen , Uraco/cirugía , Bazo/diagnóstico por imagen , Bazo/cirugía , Tomografía Computarizada por Rayos X , Biopsia
6.
Molecules ; 28(10)2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37241792

RESUMEN

An N-heterocyclic carbene (NHC)-catalyzed atroposelective annulation reaction is disclosed for quick and efficient access to thiazine derivatives. A series of axially chiral thiazine derivatives bearing various substituents and substitution patterns were produced in moderate to high yields with moderate to excellent optical purities. Preliminary studies revealed that some of our products exhibit promising antibacterial activities against Xanthomonas oryzae pv. oryzae (Xoo) that causes rice bacterial blight.

7.
Arch Insect Biochem Physiol ; 111(4): e21964, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36050844

RESUMEN

Chlorantraniliprole (CAP) is an insecticide widely used to control the small white butterfly (SWB), Pieris rapae. Exposure to CAP can cause oxidative injury in SWB; however, it is unclear if antioxidant enzymes are involved in the defense process. In this study, a thioredoxin peroxidase (PrTPX1) gene was identified from SWB by using a homology search method. The gene encoded a 195 amino-acid PrTPX1 protein. Sequence characteristics and phylogenetic analysis indicated that PrTPX1 was a typical "2-Cys" TPX, and the PrTPX1 gene consisted of four exons and three introns. Reverse transcription-quantitative polymerase chain reaction analysis indicated that the messenger RNA levels of PrTPX1 were highest in third-, fourth- and fifth-instar larval stages and in the larval midgut. Treatment with sublethal doses (LD20 and LD50 ) of CAP for 6, 12, 18, and 24 h resulted in increased H2 O2 concentration in SWB larvae, indicating insecticide-induced oxidative stress. The transcriptional levels of PrTPX1 were significantly enhanced in larvae exposed to CAP. Recombinant PrTPX1 protein was expressed in Escherichia coli. Enzymatic assay revealed that the protein displayed antioxidant activity and was able to protect against oxidative challenge. These results indicated that PrTPX1 plays an important role in oxidative stress responses and may contribute to the CAP tolerance in SWB.


Asunto(s)
Mariposas Diurnas , Insecticidas , Animales , Mariposas Diurnas/genética , Insecticidas/toxicidad , Insecticidas/metabolismo , Peroxirredoxinas/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Filogenia , Larva/genética , Estrés Oxidativo
8.
BMC Psychiatry ; 22(1): 257, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35413865

RESUMEN

INTRODUCTION AND OBJECTIVES: The aging population is expected to reach 2 billion by 2050, but the impact of somatic symptom disorder (SSD) on the elderly has been insufficiently addressed. We aimed to clarify the prevalence of SSD in China and to identify physical and psychological differences between the elderly and non-elderly. METHODS: In this prospective multi-center study, 9020 participants aged (2206 non-elderly adults and 6814 elderly adults) from 105 communities of Shanghai were included (Assessment of Somatic Symptom in Chinese Community-Dwelling People, clinical trial number NCT04815863, registered on 06/12/2020). The Somatic Symptom Scale-China (SSS-CN) questionnaire was used to measure SSD. Depressive and anxiety disorders were assessed by the Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7), respectively. RESULTS: The prevalence of SSD in the elderly was higher than that in the non-elderly (63.2% vs. 45.3%). The elderly suffered more severe SSD (20.4% moderate and severe in elderly vs. 12.0% in non-elderly) and are 1.560 times more likely to have the disorder (95%CI: 1.399-1.739; p < .001) than the non-elderly. Comorbidity of depressive or anxiety disorders was 3.7 times higher than would be expected in the general population. Additionally, the results of adjusted multivariate analyses identified older age, female sex, and comorbid physical diseases as predictive risk factors of SSD in the elderly group. CONCLUSIONS: With higher prevalence of common physical problems (including hypertension, diabetes mellitus and cardio/cerebrovascular disease), the elderly in Shanghai are more vulnerable to have SSD and are more likely to suffer from comorbid depressive and anxiety disorders. SSD screening should be given more attention in the elderly, especially among older females with several comorbid physical diseases.


Asunto(s)
Síntomas sin Explicación Médica , Adulto , Anciano , China/epidemiología , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Trastornos Somatomorfos/diagnóstico , Trastornos Somatomorfos/epidemiología
9.
Pestic Biochem Physiol ; 181: 104995, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35082025

RESUMEN

Lambda-cyhalothrin (LCT) is a pyrethroid insecticide widely used to control insect pests. Insect exposure to LCT may cause abnormal accumulation of reactive oxygen species (ROS) and result in oxidative damage. Heat shock proteins (HSPs) may help protect against oxidative stress. However, little is known about the role of HSPs in response to LCT in the green peach aphid, Myzus persicae. This insect is an important agricultural pest causing severe yield losses in crops. In this study, we characterized a cDNA sequence (MpHsp70) encoding a member of the HSP70 family in M. persicae. MpHsp70 encoded a 623 amino acid protein putatively localized in the cytosol. The highest expression level of MpHsp70 occurred in fourth-instar nymphs. Treatment of M. persicae with LCT resulted in oxidative stress and significantly increased H2O2 and malondialdehyde levels. This led to an elevated transcription level of MpHsp70. Injection of H2O2 into M. persicae also upregulated the MpHsp70 expression level, suggesting that MpHsp70 is responsive to ROS, particularly H2O2, induced by LCT. Recombinant MpHSP70 protein was expressed in Escherichia coli. E. coli cells overexpressing MpHSP70 exhibited significant tolerance to H2O2 and the ROS generators, cumene hydroperoxide and paraquat. This indicated that MpHSP70 protects against oxidative stress. Furthermore, knockdown of MpHsp70 by RNA interference resulted in increased susceptibility in apterous adults of M. persicae to LCT. These findings indicate that MpHsp70 plays an important role in defense against LCT-induced oxidative stress and insecticide susceptibility in M. persicae.


Asunto(s)
Áfidos , Piretrinas , Animales , Áfidos/genética , Escherichia coli , Proteínas de Choque Térmico/genética , Peróxido de Hidrógeno/toxicidad , Nitrilos , Estrés Oxidativo , Piretrinas/toxicidad
10.
J Insect Sci ; 22(1)2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34958664

RESUMEN

Plant essential oils, with high bioactivity and biodegradability, provide promising alternatives to synthetic pesticides for pest control. Trans-anethole is the major component of essential oil from star anise, Illicium verum Hook. The compound has a strong contact toxicity against the green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), which is a major insect pest of many vegetables and crops. However, little information is known about how M. persicae responds to trans-anethole at the molecular level. We conducted a comparative transcriptome analysis of M. persicae in response to a LD50 dose of trans-anethole. A total of 559 differentially expressed genes were detected in the treated individuals, with 318 genes up-regulated, and 241 genes down-regulated. Gene ontology (GO) analysis revealed that these genes were classified into different biological processes and pathways. We also found that genes encoding ATP-binding cassette (ABC) transporters, DnaJ, and cuticle proteins were dramatically up-regulated in response to trans-anethole. To study the function of these genes, we performed RNA interference (RNAi) analysis. Knockdown of an ABC transporter gene (ABCG4) and a DnaJ gene (DnaJC1) resulted in a significantly increased mortality rate in M. persicae following trans-anethole exposure, indicating the involvement of these two genes in the toxicity response to trans-anethole. The findings provide new insights into the mechanisms of M. persicae in coping with plant essential oils.


Asunto(s)
Derivados de Alilbenceno , Anisoles , Áfidos , Proteínas de Insectos/genética , Aceites Volátiles , Derivados de Alilbenceno/farmacología , Animales , Anisoles/farmacología , Áfidos/efectos de los fármacos , Áfidos/genética , Expresión Génica , Aceites Volátiles/farmacología
11.
Arch Insect Biochem Physiol ; 108(2): e21835, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34309077

RESUMEN

The green peach aphid, Myzus persicae (Sulzer), is a serious agricultural pest with a worldwide distribution. Catalase (CAT), which is encoded by the catalase (Cat) gene, is an extremely important antioxidant enzyme that plays a pivotal role in protecting cells against the toxic effects of hydrogen peroxide. The Cat gene has not been characterized in M. persicae; therefore, this study describes the identification of the Cat (MpCat) gene from M. persicae. MpCat contains an open reading frame of 1515 bp and encodes a MpCAT protein consisting of 504 amino-acid residues. MpCAT possesses features typical of other insect catalases, including 7 conserved amino acids involved in binding heme and 15 involved in binding nicotinamide adenine dinucleotide phosphate. Phylogenetic analysis showed that MpCAT was closely related to orthologs from other aphid species. MpCat consisted of nine exons and eight introns, and the number and insertion sites of introns are consistent with those of Cat genes from Acyrthosiphon pisum (Harris) and Aphis gossypii Glover. The mRNA transcripts of MpCat were detected at all tested developmental stages, with the highest mRNA level in alate adults. The expression of MpCat was significantly upregulated when M. persicae was exposed to low and high temperatures, ultraviolet radiation, Beauveria bassiana, and permethrin. The transcription of MpCat and the activity of catalase were suppressed by RNA interference, and knockdown of MpCat significantly reduced the survival rate in M. persicae under heat stress. The results provide valuable information for further study on the physiological functions of MpCat.


Asunto(s)
Áfidos , Catalasa , Animales , Antioxidantes/metabolismo , Áfidos/genética , Áfidos/metabolismo , Catalasa/genética , Catalasa/metabolismo , Perfilación de la Expresión Génica , Genes de Insecto , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Filogenia , Interferencia de ARN
12.
Breast J ; 27(12): 890-894, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34672049

RESUMEN

Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type.


Asunto(s)
Neoplasias de la Mama , Rabdomiosarcoma Embrionario , Rabdomiosarcoma , Adulto , Mama/patología , Neoplasias de la Mama/patología , Niño , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Rabdomiosarcoma/patología , Rabdomiosarcoma Embrionario/diagnóstico por imagen , Rabdomiosarcoma Embrionario/patología , Adulto Joven
13.
Pestic Biochem Physiol ; 174: 104825, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33838718

RESUMEN

Insecticide exposure typically leads to abnormally high levels of reactive oxygen species (ROS) and oxidative damage in insects. Superoxide dismutases (SODs) are potent antioxidant enzymes for ROS scavenging that are essential to protect insects against insecticide-induced oxidative injury. The small white butterfly, Pieris rapae, is an economically important lepidopteran pest of cruciferous crops, and the anthranilic diamide insecticide chlorantraniliprole is widely used to control this organism. However, whether chlorantraniliprole causes oxidative stress, and whether SODs are involved in ROS scavenging, remains unclear in P. rapae. In this study, an intracellular copper/zinc SOD (designated PrSOD1) gene was identified and characterised in P. rapae. The gene consists of four exons and three introns, and the PrSOD1 protein encoded by the gene has typical highly conserved features of CuZnSODs, including two signature motifs and seven Cu/Zn-interacting residues. Transcription of PrSOD1 was highest in the larval fat body and at the fifth-instar larval stage. Recombinant PrSOD1 protein expressed in Escherichia coli displayed antioxidant activity and high thermal and pH stability, confirming that PrSOD1 encodes a functional enzyme. Exposure to three sublethal doses of chlorantraniliprole for 6, 12 or 24 h resulted in significantly increased malondialdehyde concentration in P. rapae larvae, indicating insecticide-induced oxidative stress. Furthermore, both PrSOD1 transcription levels and CuZnSOD activity were quickly (6 and 12 h, respectively) upregulated in larvae subjected to chlorantraniliprole, strongly suggesting that PrSOD1 plays an important role in protecting against oxidative damage and possibly chlorantraniliprole tolerance in P. rapae.


Asunto(s)
Mariposas Diurnas , Animales , Cobre/toxicidad , Estrés Oxidativo , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Zinc , ortoaminobenzoatos
14.
Small ; 16(41): e2002836, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32964691

RESUMEN

Precise molecular and ion separations depend largely on the size and uniformity of the nanochannels in a defect-free microporous nanofilm. Ordered and perpendicular nanochannels with uniform pore size are assembled into a continuous and defect-free film by a "gel nuclei-less" route. The ultrathin (<50 nm) zeolite nanosheets seeding layer induces the formation of defect-free zeolite nanofilms (500-800 nm) with preferential [100] orientation well-aligned to the transport pathway. The large-area and thin silicoaluminophosphate-34 (SAPO-34) nanofilm consisting of uniform and straight nanochannels shows a milestone CO2 permeance of ≈1.0 × 10-5 mol (m2 s Pa)-1 and high CO2 /CH4 and CO2 /N2 selectivities of 135 and 41 in equimolar binary mixtures at room temperature and 0.2 MPa feed pressure, respectively. These results suggest that highly oriented and thin SAPO-34 nanofilms prepared from nanosheets might have great potential for CO2 capture from natural gas, biogas, and flue gas.

15.
J Insect Sci ; 20(5)2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32889524

RESUMEN

The small white butterfly, Pieris rapae (L.), is an important insect pest of Brassica crops. This species utilize olfactory cues to find their hosts and mates. However, the molecular mechanism underlying the olfactory perception in this species remains unclear. Here, we identified 14 odorant-binding proteins (OBP) genes-essential for insect olfaction-in P. rapae by exploring a previously published transcriptome dataset. Proteins encoded by all of these genes contain N-terminal signal peptides and six positionally conserved cysteine residues, which are characteristic of insect OBPs. These OBPs displayed high amino acid identity with their respective orthologs in other lepidopterans, and several conserved motifs were identified within these OBPs. Phylogenetic analysis showed that these OBPs were well segregated from each other and clustered into different branches. PrapOBP1 and PrapOBP2 were clustered into the 'general odorant-binding protein' clade, and PrapOBP3 and PrapOBP4 fall into the 'pheromone-binding protein' clade. The 14 OBP genes were located on seven genomic scaffolds. Of these, PrapOBP1, 2, 3, and 4 were located on scaffold332, whereas PrapOBP5, 6, 7, 8, and 9 were located on scaffold116. Ten of the 14 genes had antenna-biased expression. Of these, PrapOBP1, 2, 4, and 13 were enriched in male antennae, whereas PrapOBP7 and PrapOBP10 were female-biased. Our findings suggest that these OBPs may be involved in olfactory communication. To the best of our knowledge, this is the first report on the identification and characterization of OBPs in P. rapae, and our findings provide a solid foundation for studying the functions of these genes.


Asunto(s)
Mariposas Diurnas/genética , Proteínas de Insectos/genética , Receptores Odorantes/genética , Transcriptoma , Secuencia de Aminoácidos , Animales , Mariposas Diurnas/metabolismo , Femenino , Perfilación de la Expresión Génica , Proteínas de Insectos/química , Proteínas de Insectos/metabolismo , Masculino , Filogenia , Receptores Odorantes/química , Receptores Odorantes/metabolismo , Alineación de Secuencia
16.
J Org Chem ; 84(11): 7291-7302, 2019 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-31099249

RESUMEN

An asymmetric synthesis, amenable to library preparation of structurally diverse P-chiral t-butyl substituted secondary phosphine oxides (SPOs) and tertiary phosphine oxides (TPOs), was developed. A P-chiral H-phosphinate building block was prepared via a two-step, one-pot condensation of a chiral auxiliary with t-BuPCl2, followed by hydrolysis. Nucleophilic displacement of the chiral auxiliary with Grignard reagents, followed by hydrolysis, provided a library of P-chiral SPOs. In situ treatment of the prehydrolysis intermediate with electrophiles also provided a library of P-chiral TPOs in high enantiomeric purity.

17.
Appl Opt ; 58(3): 616-625, 2019 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-30694245

RESUMEN

For double-pulsed 1.57 µm integrated path differential absorption lidar, the transmitted pulse energy measurement is an important factor that can influence the uncertainty of CO2 concentration measurement. An energy monitoring experiment was performed to determine how to improve the measurement precision of the transmitted pulse energy. Ground glass diffusers were used to reduce the speckle effect during energy monitoring. The roughness and rotational speed of the ground glass diffusers were considered and compared. The normalized energy ratios between on-line and off-line echo pulses and on-line and off-line energy monitoring pulses were analyzed, and the Allan deviation was used to evaluate the energy monitoring results. Averaging 148 shots, the standard deviation of the normalized energy ratio reached 0.0757%, whereas the correlation between the energy ratio of the on-line and off-line energy monitoring pulses and the energy ratio of the on-line and off-line echo pulses was higher than 90%.

18.
Arch Insect Biochem Physiol ; 99(1): e21476, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29873106

RESUMEN

In insects, thioredoxin peroxidase (TPX) plays an important role in protecting against oxidative damage. However, studies on the molecular characteristics of TPXs in the Asiatic rice borer, Chilo suppressalis, are limited. In this work, a cDNA sequence (CsTpx3) encoding a TPX was identified from C. suppressalis. The deduced CsTPX3 protein shares high sequence identity and two positionally conserved cysteines with orthologs from other insect species, and was classified as a typical 2-Cys TPX. CsTpx3 was expressed most highly during the fifth-instar larval stage, and transcripts were most abundant in the midgut. Recombinant CsTPX3 protein expressed in Escherichia coli displayed the expected peroxidase activity by removing H2 O2 . Furthermore, CsTPX3 protected DNA from oxidative damage, and E. coli cells overexpressing CsTPX3 exhibited long-term resistance to oxidative stress. Exposure to various oxidative stressors, such as cold (8°C), heat (35°C), bacteria (E. coli), and two insecticides (chlorpyrifos and lambda-cyhalothrin), significantly upregulated transcription of CsTpx3. However, exposure to abamectin had no such effect. Our results provide valuable information for future studies on the antioxidant mechanism in this insect species.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Proteínas de Insectos/genética , Mariposas Nocturnas/genética , Estrés Oxidativo/genética , Peroxirredoxinas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Femenino , Proteínas de Insectos/química , Proteínas de Insectos/metabolismo , Larva/enzimología , Larva/genética , Larva/crecimiento & desarrollo , Masculino , Mariposas Nocturnas/enzimología , Mariposas Nocturnas/crecimiento & desarrollo , Peroxirredoxinas/química , Peroxirredoxinas/metabolismo , Filogenia , Pupa/enzimología , Pupa/genética , Pupa/crecimiento & desarrollo , Alineación de Secuencia
19.
Arch Insect Biochem Physiol ; 98(1): e21455, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29532954

RESUMEN

The small white butterfly, Pieris rapae (Lepidoptera: Pieridae), is an important pest on Brassicaceae plants, causing heavy crop loss each year. Cytochrome P450 monooxygenase (CYP) is a superfamily of enzymes involved in the detoxification of various xenobiotic compounds, including insecticides. However, little is known about the role of CYP genes in P. rapae. In this study, we identified 63 CYP genes in P. rapae, and analyzed their phylogenetic relationships, exon-intron structures and genomic locations. Moreover, our insecticide-response transcription profiling showed that LD5 doses of lambda-cyhalothrin, chlorantraniliprole, and abamectin significantly increased expression of five (CYP4M59, CYP6AE119, CYP6AE120, CYP6AE121, and CYP6BD18), three (CYP4AU1, CYP6AE120, and CYP6AW1), and five (CYP4L40, CYP4AU1, CYP6AE119, CYP6AW1, and CYP6BD19) CYP genes, respectively; and LD20 doses of the three pesticides significantly upregulated six (CYP4M59, CYP6AE119, CYP6AE120, CYP6AE121, CYP4AU1, and CYP6BD18), six (CYP4G168, CYP4L40, CYP4AU1, CYP6AE120, CYP6AW1, and CYP6BD19), and five (CYP4L40, CYP4AU1, CYP6AB108, CYP6AE119, and CYP6BD19) genes, respectively. When we used LD50 doses of the three insecticides, we reported significantly elevated expression levels of five (CYP4M59, CYP6AE119, CYP6AE120, CYP6BD17, and CYP6BD18), eight (CYP4G168, CYP4L40, CYP4AU1, CYP6AE120, CYP6AE121, CYP6AW1, CYP6BD18, and CYP6BD19), and six (CYP4L40, CYP4S34, CYP6AB108, CYP6AE119, CYP6AE120, and CYP6BD19) genes, respectively. Our expression analysis also revealed that five (CYP4G168, CYP4G169, CYP4S34, CYP6AW1, and CYP6CT3) and three (CYP4L40, CYP6AN33, and CYP6BD17) CYP genes were mainly expressed in the midgut and fat body, respectively, and one CYP gene (CYP6AE119) in the Malpighian tubules. This is the first large-scale report into the characterization of CYP genes in P. rapae.


Asunto(s)
Mariposas Diurnas/enzimología , Sistema Enzimático del Citocromo P-450/genética , Proteínas de Insectos/genética , Insecticidas/farmacología , Animales , Mariposas Diurnas/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/metabolismo , Femenino , Expresión Génica , Proteínas de Insectos/metabolismo , Larva/efectos de los fármacos , Larva/enzimología , Dosificación Letal Mediana , Masculino , Filogenia
20.
BMC Cancer ; 17(1): 861, 2017 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-29246203

RESUMEN

BACKGROUND: The significance of PLK1 (polo-like kinase 1) has become increasingly essential as both a biomarker and a target for cancer treatment. Here, we aimed to determine the downstream genes of PLK1 and their effects on the carcinogenesis and progression of bladder cancer. METHODS: Specific siRNA was utilized to silence the target gene expression. The cell proliferation, invasion and migration of bladder cancer cells by MTT assay, BrdU assay and transwell assay. The differential expression genes were identified using Affymetrix HTA2.0 Array. The KEGG, GO and STRING analysis were used to analyze the signaling pathway and protein-protein interaction. Spearman analysis was used to analyze the correlation between protein and protein, between protein and clincopathologic characteristics. RESULTS: PLK1 siRNA hindered the proliferation, invasion and migration of bladder cancer cells, as determined by the MTT, BrdU and transwell assays. A total of 561 differentially expressed genes were identified using an Affymetrix HTA2.0 Array in PLK1 knockdown T24 cells. According to KEGG, GO and STRING analysis, five key genes (BUB1B, CCNB1, CDC25A, FBXO5, NDC80) were determined to be involved in cell proliferation, invasion and migration. PLK1 knockdown decreased BUB1B, CCNB1, CDC25A and NDC80 expressions but increased FBXO5 expression. BUB1B, CCNB1, CDC25A and NDC80 were positively correlated with cell proliferation, invasion, migration and PLK1 expression in tissues, but FBXO5 was negatively correlated with each of those factors. The results showed that the five genes expressions were significantly correlation with the PLK1 expression in normal bladder tissues and bladder cancer tissues. Four of them (BUB1B, CCNB1, CDC25A, NDC80) were obviously positive correlations with pT stage and metastasis. But FBXO5 was negative correlated with pT stage and metastasis. Furthermore, significant correlations were found between CCNB1 or CDC25A or NDC80 and histological grade; between BUB1B or NDC80 and recurrence. CONCLUSION: Five downstream genes of PLK1 were associated with the regulation of cell proliferation, invasion and migration in bladder cancer. Furthermore, these genes may play important roles in bladder cancer and become important biomarkers and targets for cancer treatment.


Asunto(s)
Carcinogénesis/genética , Proteínas de Ciclo Celular/metabolismo , Regulación Neoplásica de la Expresión Génica , Recurrencia Local de Neoplasia/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Neoplasias de la Vejiga Urinaria/genética , Apoptosis/genética , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Progresión de la Enfermedad , Perfilación de la Expresión Génica/métodos , Técnicas de Silenciamiento del Gen , Humanos , Invasividad Neoplásica/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Mapas de Interacción de Proteínas/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , ARN Interferente Pequeño/metabolismo , Transducción de Señal/genética , Programas Informáticos , Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/patología , Quinasa Tipo Polo 1
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