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Correlation between PRDX2 and spermatogenesis under oxidative stress. Biochem Biophys Res Commun 2023; 656:139-145. [PMID: 36963350 DOI: 10.1016/j.bbrc.2023.03.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 03/17/2023] [Indexed: 03/22/2023]
Abstract
BACKGROUND Obesity is one of the world's diseases that endanger human health, causing systemic inflammation caused by excessive reactive oxygen damage. An increase in the proportion of obese people with reduced sperm motility has been reported. But the mechanism behind it remains unclear. Peroxiredoxin 2 (PRDX2) is a member of the peroxidase family that effectively removes hydrogen peroxide. This study is to clarify the expression of PRDX2 in the testes of obese mice and lay a foundation for further exploration of the regulatory and protective effects of PRDX2 on spermatogenesis. METHOD A model of high-fat-induced obesity in animals was constructed, and the expression of PRDX2 in the testes of the two groups was detected by immunohistochemistry, western blotting, immunofluorescence and other techniques. Hydrogen peroxide (H2O2) and cholesterol were co-cultured in testicular support cells for 48 h to observe the expression of PRDX2. RESULT PRDX2 expression was reduced in the testes of the obese group, and immunohistochemistry showed that it was mainly localized to supporting cells. H2O2 inhibits the expression of PRDX2 in Sertoli cells, and high cholesterol upregulates the expression of PRDX2 in Sertoli cells. CONCLUSION PRDX2 has some antioxidant properties against changes in the testicular environment caused by HFD. And under short-term oxidative stress to enhance its antioxidant capacity. PRDX2 may be involved in maintaining the oxidative balance of the spermatogenesis environment.
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Correlation between the contrast-enhanced ultrasound image features and axillary lymph node metastasis of primary breast cancer and its diagnostic value. Clin Transl Oncol 2020; 23:155-163. [PMID: 32488804 DOI: 10.1007/s12094-020-02407-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/20/2020] [Indexed: 12/29/2022]
Abstract
PURPOSE To analyze the correlation between contrast-enhanced ultrasound image features and axillary lymph node metastasis of primary breast cancer and its diagnostic value. METHODS In this study, 64 patients with axillary lymph node metastasis of primary breast cancer diagnosed and treated in our hospital from February 2011 to March 2013 were collected as an observation group, and 54 patients without axillary lymph node metastasis were collected as a control group. All patients underwent a contrast-enhanced ultrasound examination, and the correlation between the contrast-enhanced ultrasound image features and axillary lymph node metastasis and its diagnostic value were analyzed. They were divided into two groups according to their survival conditions: the group with good efficacy and group with poor efficacy, and the prognostic factors of breast cancer in the two groups were analyzed. RESULTS There were statistical differences in the peripheral acoustic halo, blood flow classification, ratio of length to diameter (L/D), maximum cortical thickness, and enhancement mode of lymph nodes between the two groups (p < 0.05). The area under ROC curve for diagnosis of axillary lymph node metastasis by contrast-enhanced ultrasound was 0.854, sensitivity was 83.33%, and specificity was 87.5%; L/D and enhancement mode were independent prognostic factors for breast cancer. CONCLUSIONS Contrast-enhanced ultrasound image features have diagnostic and prognostic value for axillary lymph node metastasis of breast cancer.
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[Meta-analysis on safety and efficacy of dual antiplatelet therapy combining with proton pump inhibitors for patients after percutaneous coronary intervention]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 2019; 47:129-140. [PMID: 30818941 DOI: 10.3760/cma.j.issn.0253-3758.2019.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To analyze the impact of dual antiplatelet (DAPT) therapy combining with or without proton pump inhibitors (PPI) on the main outcomes after percutaneous coronary intervention (PCI). Methods: The PubMed, EMBASE and Cochrane Library were searched for relevant literature and the references obtained from these sources were retrieved manually from inception till September 2017. Inclusion and exclusion criteria were established follow the Cochrane review standard. A total of 977 literatures were included, 193 duplicates were excluded, 74 reviews, case reports, letters and systematic reviews were excluded, 667 literatures were excluded after reading the title and abstract, 34 literatures were excluded due to non-randomized control studies and unrelated outcome indicators, and 9 literatures were finally included with a total of 16 589 patients. RevMan 5.3 software was used to compare the incidence of major adverse cardiovascular events (MACE), cardiogenic death, recurrent myocardial infarction, target vessel revascularization, all-cause death, stent thrombosis, stroke, gastrointestinal bleeding and gastrointestinal events in patients with DAPT combining with or without PPI after PCI. Results: MACE was observed in 8 out of the 9 included literatures, and the results showed that MACE occurred in 561 out of 6 282 patients receiving DAPT combining with PPI therapy and in 951 out of 9 632 patients using DAPT alone (OR=1.15, 95%CI 0.88-1.51, P>0.05). Cardiogenic death was observed in 7 out of the 9 included literatures, and the results showed that cardiogenic death occurred in 172 out of 6 453 patients receiving DAPT combining with PPI treatment and in 321 out of the 9 839 patients using DAPT alone (OR=0.97, 95%CI 0.80-1.18, P>0.05). Recurrent myocardial infarction was observed in 7 out of the 9 included literatures, the results showed 416 out of 6 282 cases in DAPT combining with PPI therapy group experienced recurrent myocardial infarction and 691 out of 9 632 cases in DAPT group experienced recurrent myocardial infarction (OR=1.01, 95%CI 0.89-1.16, P>0.05). Four out of 9 literatures observed revascularization. The results showed that revascularization was performed in 64 out of 2 173 patients receiving DAPT combining with PPI therapy and in 105 out of the 2 770 patients using DAPT alone (OR=1.33, 95%CI 0.55-3.24, P>0.05). All-cause death was observed in 7 out of the 9 included literatures, and the results showed that all-cause death occurred in 172 out of the 6 453 patients in DAPT combining with PPI therapy group and in 321 out of the 9 839 patients using DAPT alone (OR=0.97, 95%CI 0.80-1.18, P>0.05). Three out of the 9 included articles observed stent thrombosis, and the results showed that stent thrombosis occurred in 99 out of 2 997 patients receiving DAPT combining with PPI therapy and in 245 out of the 6 198 patients treated with DAPT (OR=1.07, 95%CI 0.83-1.37, P>0.05). Stroke was observed in 2 out of the 9 included literatures. The results showed that stroke occurred in 5 out of 2 019 patients receiving DAPT combining with PPI therapy, and in 4 out of the 2 033 patients treated with DAPT (OR=1.00, 95%CI 0.29-3.49, P>0.05). Gastrointestinal bleeding was observed in 6 out of the 9 included literatures. The results showed that gastrointestinal bleeding occurred in 26 out of 3 517 patients receiving DAPT combined with PPI therapy, and in 93 out of the 3 506 patients treated with DAPT, gastrointestinal bleeding was significantly lower in the DAPT combining with PPI group than DAPT alone group (OR=0.27, 95%CI 0.17-0.41, P<0.01). Gastrointestinal events were reported in 6 out of the 9 included articles. Similarly, gastrointestinal events were observed in 51 out of 3 517 patients receiving DAPT combined with PPI therapy, and in 190 out of the 3 506 patients treated with DAPT alone, the incidence of gastrointestinal events in the DAPT combined with PPI group was significantly lower than DAPT alone group (OR=0.24, 95%CI 0.14-0.42, P<0.01). Conclusions: The incidence of MACE, cardiogenic death, recurrent myocardial infarction, target vessel revascularization, all-cause death, stent thrombosis and stroke are not affected by DAPT combined with PPI therapy after PCI, while the incidence of gastrointestinal bleeding and gastrointestinal events could be reduced by adding PPI to DAPT in patients undergoing PCI.
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[Influential factors for failure of enhanced recovery after surgery from hepatectomy for hepatocellular carcinoma and the establishment of risk prediction model]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2018; 56:693-700. [PMID: 30157576 DOI: 10.3760/cma.j.issn.0529-5815.2018.09.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the influential factors for failure of enhanced recovery after surgery(ERAS) from hepatectomy for hepatocellular carcinoma(HCC) patients and then to establish a risk prediction model. Methods: The relevant clinical data of 180 patients with HCC undergoing hepatectomy at Department of Hepatic Surgery, Affiliated Provincial Hospital, Anhui Medical University from January 2016 to June 2017 were analyzed retrospectively.There were 149 male patients and 31 female patients aging of (56.5±11.0)years(from 33 to 84 years old). The factors affecting postoperative failure of ERAS of HCC patients were identified by univariate and multivariate analyses, and then, all the obtained factors and their statistical values were used to establish the risk prediction model. Results: A total of 23 patients failed in the ERAS protocol(12.8%). The preoperative total bilirubin (TBIL), alanine aminotransferase(ALT) and amount of intraoperative bleeding were independent risk factors for failure of ERAS from hepatectomy(all P<0.05). The obtained risk prediction model was presented as follows: risk coefficient(R)=0.114×(TBIL)+ 0.082×(ALT)+ 0.008×(amount of intraoperative bleeding). At the cut of value of R=7.90, the area under the ROC curve of this model for predicting failure of ERAS was 0.866(95%CI: 0.788-0.945, P<0.01), with the sensitivity and specificity of 69.6% and 91.1%, respectively.External validation results indicated that the scoring system had good differential ability(area under the ROC curve=0.889, 95%CI: 0.811-0.967, P<0.01). Conclusions: Higher level of preoperative TBIL(>21 μmol/L) and ALT(>50 U/L) and the larger amount of intraoperative bleeding (more than 400 ml) are independent risk factors for failure of ERAS inpatients undergoing hepatectomy for HCC and the established prediction model may have certain value for risk assessment.
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Abstract
BACKGROUND Renal cancer is one of the common malignant tumors of the urinary system, seriously threatening human being's health. The current discoveries, however, are far enough for efficient and secure treatment of renal cancer. AIMS The aim was to explore the mechanism of matrix metalloproteinase-7 (MMP-7) protein in renal carcinoma cell metastasis by bioinformatics analysis. MATERIALS AND METHODS Bioinformatics methods were used to analyze the composition of amino acids, as well as transmembrane structure, coiled coils, subcellular localization, signal peptide, functions and structures at all levels. RESULTS AND CONCLUSIONS It showed that the gene MMP-7 totally had 1131 bp. A peptide chain containing 267 amino acids was encoded in the coding region. Based on random coil, α helix, and further super-helix, it had formed a stable neutral hydrophilic protein. The subcellular location analysis indicated that the protein was located outside the cell. The mature peptide started from the 18th amino acid, and its front-end was the sequence of the signal peptide, belonging to the secreted protein. Analysis of the functional domain showed that this protein had two functional domains, the PG binding domain, and the zinc finger binding domain. Moreover, the protein, which was cross-linked with it, was also one related to cancer cell proliferation and metastasis. To sum up, MMP-7 is a stable neutral hydrophilic secreted protein, and it may play a vital role in the invasion and metastasis of cancer cells.
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Abstract
Deep brain stimulation (DBS) has provided remarkable therapeutic benefits for people with a variety of neurological disorders. Despite the uncertainty of the precise mechanisms underlying its efficacy, DBS is clinically effective in improving motor function of essential tremor, Parkinson's disease and primary dystonia and in relieving obsessive-compulsive disorder. Recently, this surgical technique has continued to expand to other numerous neurological diseases with encouraging results. This review highlighted the current and potential future clinical applications of DBS.
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High preoparative levels of serum periostin are associated with poor prognosis in patients with hepatocellular carcinoma after hepatectomy. EUROPEAN JOURNAL OF SURGICAL ONCOLOGY 2013; 39:1129-35. [PMID: 23916473 DOI: 10.1016/j.ejso.2013.06.023] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 05/07/2013] [Accepted: 06/17/2013] [Indexed: 01/06/2023]
Abstract
AIMS Periostin (POSTN) is implicated in cancer development and progression. The aim of this study was to evaluate the diagnostic and prognostic significance of serum POSTN in patients with hepatocellular carcinoma (HCC) receiving curative surgery. METHODS Enzyme-linked immunosorbent assay was performed to determine serum POSTN levels in 69 healthy volunteers, 30 patients with hepatolithiasis, 27 patients with cirrhosis, and 56 HCC patients. The relationships between serum POSTN and clinicopathologic features were analyzed. Receiver operating characteristics analysis was used to calculate diagnostic accuracy of serum POSTN, serum alpha-fetoprotein (AFP), and their combination. The prognostic impact of serum POSTN on overall survival (OS) and relapse-free survival (RFS) was also investigated. RESULTS The median serum POSTN level was significantly (P < 0.05) increased in HCC patients, compared to healthy controls, patients with hepatolithiasis, and patients with liver cirrhosis. Elevated serum POSTN was only significantly associated with Edmondson grade (P = 0.007). The combination of serum POSTN and AFP had a markedly higher area under the curve (0.805 (95% confidence interval [CI]: 0.677-0.932)) than POSTN (0.582 (95% CI: 0.427-0.736)) or AFP (0.655 (95% CI: 0.504-0.806)) alone. Kaplan-Meier analysis indicated that elevated serum POSTN was associated with OS (P = 0.031) and RFS (P = 0.027). Moreover, multivariate analysis revealed elevated serum POSTN as an independent poor prognostic marker for OS and RFS. CONCLUSIONS Preoperative serum POSTN has limited diagnostic value in distinguishing HCC from non-malignant liver diseases, but serves as independent prognostic biomarker in HCC patients.
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Abstract
Dimers of [Ru(2)(Xap)(4)] bridged by 1,3,5-hexatriyn-diyl (Xap are 2-anilinopyridinate and its aniline substituted derivatives), [Ru(2)(Xap)(4)](2)(μ-C(6)) (1), were prepared. Compounds 1 reacted with 1 equiv of tetracyanoethene (TCNE) to yield the cyclo-addition/insertion products [Ru(2)(Xap)(4)](2){μ-C≡CC(C(CN)(2))-C(C(CN)(2))C≡C} (2) and 1 equiv of Co(2)(dppm)(CO)(6) to yield the η(2)-Co(2) adducts to the middle C≡C bond, [Ru(2)(Xap)(4)](2)(μ-C(6))(Co(2)(dppm)(CO)(4)) (3). Voltammetric and spectroelectrochemical studies revealed that (i) two Ru(2) termini in 1 are sufficiently coupled with the monoanion (1(-)) as a Robin-Day class II/III mixed valence species; (ii) the coupling between two Ru(2) is still significant but somewhat weakened in 3; and (iii) the coupling between two Ru(2) is completely removed by the insertion of TCNE in 2. The attenuation of electronic couplings in 2 and 3 was further explored with both the X-ray diffraction study of representative compounds and spin-unrestricted DFT calculations.
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Diruthenium Complexes of Axial Ferrocenyl−Polyynyl Ligands: The Cases of C6Fc and C8Fc. Organometallics 2009. [DOI: 10.1021/om801227q] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Screening of Chinese medicinal plants for inhibition against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA). JOURNAL OF ETHNOPHARMACOLOGY 2008; 120:287-290. [PMID: 18804522 DOI: 10.1016/j.jep.2008.08.021] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 08/07/2008] [Accepted: 08/20/2008] [Indexed: 05/26/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Traditional herbs are a valuable source of novel antibacterials in combating pathogenic isolates of methicillin-resistant Staphylococcus aureus (MRSA), a global nosocomial problem. AIM OF THE STUDY To assess in vitro anti-MRSA activity of extracts from Chinese herbs. The minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) were determined in the setting of clinical MRSA isolates. MATERIALS AND METHODS A collection of 19 plant extracts were obtained and bioassay-guided phytochemical analysis performed. Antibacterial susceptibilities were screened for inhibitory zone and MICs/MBCs determined by serial dilution with a standardized microdilution broth methodology. 9 MRSA isolates and a standard control strain (ATCC 25923) were cultured and exposed to the plant extract and isolated compound. Vancomycin was used as a positive control agent. RESULTS All the presented 19 plants showed anti-MRSA activity with MIC of 1.25-3.07mg/ml. The most active antimicrobial plants were Dendrobenthamia capitata, Elsholtzia rugulosa, Elsholtzia blanda, Geranium strictipes and Polygonum multiflorum (MIC< or =1.43mg/ml), and betulinic acid isolated from the active ethyl acetate fraction of Dendrobenthamia capitata extract was determined with MIC/MBC values as 62.5/125.0mg/ml. CONCLUSIONS Dendrobenthamia capitata, Elsholtzia rugulosa, Elsholtzia blanda, Geranium strictipesPolygonum multiflorum and betulinic acid demonstrate promising anti-MRSA potential.
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[The correlation between the polyomavirus DNA load and the dose of immunosuppressant]. ZHONGHUA SHI YAN HE LIN CHUANG BING DU XUE ZA ZHI = ZHONGHUA SHIYAN HE LINCHUANG BINGDUXUE ZAZHI = CHINESE JOURNAL OF EXPERIMENTAL AND CLINICAL VIROLOGY 2008; 22:272-274. [PMID: 19105341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE To explore the correlation between the polyomavirus DNA load and the dose of immunosuppressant in patients with allogene bone marrow transplantation (allo-BMT) for preventing the development of post-transplantational hemorrhagic cystitis. METHODS Serial blood and urine samples from 122 cases of allo-BMT recipients were obtained and DNA was extracted from urine samples. Polyomavirus DNA-specific probe was synthesized and Fluorescence quantitative polymerase chain reaction was used for detecting the polyomavirus DNA loads and Fluorescence polarization immunoassay (FPIA) was performed for determining the dose of immunosuppressant Cyclosporin A (CsA) in blood. RESULTS The altered polyomavirus DNA load in urine was followed by concentration of CsA in blood. When the concentration of CsA in blood was higher than 86-105 ng/ml, the positive rate of polyomavirus DNA load was significantly increased and both presented the linable correlation. CONCLUSION In immunosuppression condition, polyomavirus DNA load correlated to the dose of immunosuppressant, which increased the risk of post-transplantational hemorrhagic cystitis.
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Bis-alkynyl Diruthenium Compounds with Built-in Electronic Asymmetry: Toward an Organometallic Aviram–Ratner Diode. Chemistry 2007; 13:6874-82. [PMID: 17616963 DOI: 10.1002/chem.200700655] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Conditions to prepare trans-[Ru2(dmba)4(C[triple chemical bond]CAr)2] from [Ru2(dmba)4(NO(3))2] (DMBA=N,N'-dimethylbenzamidinate) and HC[triple chemical bond]CAr were optimized; Et2NH was found to be the most effective among a number of weak bases in facilitating the product formation. Furthermore, a series of unsymmetric trans-[(ArC[triple chemical bond]C)Ru(2)(dmba)4(C[triple chemical bond]CAr')] compounds were prepared under optimized conditions, in which one or both of Ar and Ar' are donor (NMe2)-/acceptor (NO(2))-substituted phenyls. While the X-ray crystallographic studies revealed a minimal structural effect upon donor/acceptor substitution, voltammetric measurements indicated a significant influence of substituents on the energy level of frontier orbitals. In particular, placing a donor and an acceptor on the opposite ends of trans-[(ArC[triple chemical bond]C)Ru2(dmba)4(C[triple chemical bond]CAr')] moiety results in an energetic alignment of frontier orbitals that favors a directional electron flow, a necessary condition for unimolecular rectification.
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Suzuki Coupling at the Periphery of Diruthenium Coordination and Organometallic Compounds. Inorg Chem 2006; 45:10449-56. [PMID: 17173399 DOI: 10.1021/ic060734y] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of diruthenium compounds, Ru2(DArF)3(L")Cl (2), where the auxiliary ligand DArF is DmAniF or D(3,5-Cl2Ph)F and L" is one of the diarylformamidinate ligands containing at least one biphenyl, were prepared from Suzuki reactions between Ru2(DArF)3(L')Cl (1), where L' is (4-I-Ph)NC(H)NPh (N-(4-iodophenyl)-N'-phenylformamidinate) or D(4-I-Ph)F (N,N'-di(4-iodophenyl)formamidinate), and ArB(OH)2 (Ar = Ph and 4-CH3C(O)Ph) in satisfactory yields. Alkynylation of the type 2 compounds with LiCCPh yielded the alkynyl derivatives Ru2(DArF)3(L")(CCPh) (3). Alternatively, type 3 compounds can be prepared from the Suzuki coupling reaction between Ru2(DArF)3(L')(C2Ph) and ArB(OH)2. A structural comparison between the type 1 and 2 compounds revealed minimal changes in the coordination sphere of Ru2 core. Cyclic voltammograms of Suzuki derivatives resemble those of the parent compounds, indicating the retention of the electrophore characteristic of diruthenium species upon peripheral modification.
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Abstract
Cytosine methylation is a common form of post-replicative DNA modification seen in both bacteria and eukaryotes. Modified cytosines have long been known to act as hotspots for mutations due to the high rate of spontaneous deamination of this base to thymine, resulting in a G/T mismatch. This will be fixed as a C-->T transition after replication if not repaired by the base excision repair (BER) pathway or specific repair enzymes dedicated to this purpose. This hypermutability has led to depletion of the target dinucleotide CpG outside of special CpG islands in mammals, which are normally unmethylated. We review the importance of C-->T transitions at non-island CpGs in human disease: When these occur in the germline, they are a common cause of inherited diseases such as epidermolysis bullosa and mucopolysaccharidosis, while in the soma they are frequently found in the genes for tumor suppressors such as p53 and the retinoblastoma protein, causing cancer. We also examine the specific repair enzymes involved, namely the endonuclease Vsr in Escherichia coli and two members of the uracil DNA glycosylase (UDG) superfamily in mammals, TDG and MBD4. Repair brings its own problems, since it will require remethylation of the replacement cytosine, presumably coupling repair to methylation by either the maintenance methylase Dnmt1 or a de novo enzyme such as Dnmt3a. Uncoupling of methylation from repair may be one way to remove methylation from DNA. We also look at the possible role of specific cytosine deaminases such as Aid and Apobec in accelerating deamination of methylcytosine and consequent DNA demethylation.
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Strong Electronic Couplings between Ferrocenyl Centers Mediated by Bis-Ethynyl/Butadiynyl Diruthenium Bridges. J Am Chem Soc 2005; 127:13354-63. [PMID: 16173769 DOI: 10.1021/ja0534452] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of trans-(FcC(2n))Ru(2)(Y-DMBA)(4)(C(2m)Fc) with n, m = 1 and 2 and Y-DMBA as N,N'-dimethylbenzamidinate or N,N'-dimethyl-(3-methoxy)benzamidinate have been synthesized and characterized. The intramolecular Fc...Fc distances, established through single-crystal X-ray diffraction studies, range from 11.6 to 16.6 A. Results from both voltammetric and spectroelectrochemical studies indicate that the (-C(2n))Ru(2)(Y-DMBA)(4)(C(2m-) fragments are among the most efficient mediators of intramolecular hole transfer. Density-functional calculations offer both the insight on the ground-state electronic properties and unambiguous assignment for the observed electronic absorptions.
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Diosmium(III) Compounds Supported by 2-Anilinopyridinate and Novel Alkynyl Derivatives. Inorg Chem 2005; 44:5719-27. [PMID: 16060623 DOI: 10.1021/ic050496r] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reaction between Os(2)(OAc)(4)Cl(2) and Hap (Hap is 2-anilinopyridine) under prolonged refluxing conditions resulted in an Os(III)(2) compound, Os(2)(ap)(4)Cl(2) (1), that can be crystallized as either the cis-(2,2) isomer from a CH(3)OH-CH(2)Cl(2) solution or the (3,1) isomer from a hexanes-CH(2)Cl(2) solution. Compound 1 undergoes facile reactions with LiC(2)Y to yield a series of Os(2)(ap)(4)(C(2)Y)(2) compounds with Y as Ph (2), ferrocenyl (3), SiMe(3) (4), and C(2)SiMe(3) (5). X-ray diffraction study of compound 2 reveals solvent-dependent isomerism similar to that of the parent compound 1. Compound 1 has Os-Os distances of 2.3937(8) and 2.3913(8) Angstroms for the cis-(2,2) and (3,1) isomers, respectively, and is paramagnetic (S = 1). Both the ethynyl derivatives 2-4 and butadiynyl derivative 5 are diamagnetic and have Os-Os distances of 2.456(1), 2.471(1), and 2.481(1) Angstroms for the cis-(2,2) and (3,1) isomers of 2 and (3,1) isomer of 4, respectively. Compounds 1-5 exhibit multiple one-electron redox couples in their cyclic voltammograms, including a reversible Os(2)(8+/7+) couple for 2. Resonance Raman spectra of both compounds 1 and 2 are reported.
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Ru2(ap)4(σ-oligo(phenyleneethynyl)) Molecular Wires: Synthesis and Electronic Characterization. J Am Chem Soc 2005; 127:10010-1. [PMID: 16011359 DOI: 10.1021/ja052604e] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reported in this contribution are the synthesis, characterization, and charge transport properties of wire-like Ru2(ap)4(OPEn), where ap is 2-anilinopyridinate and OPE is -(CCC6H4)nSCH2CH2SiMe3 with n = 1 (1) and 2 (2). Scanning tunneling microscopy (STM) measurements of compound 2 inserted into a SAM of C11 thiol reveal that molecule 2 exhibits (i) the stochastic switching characteristic of wire molecules embedded in insulating SAMs and (ii) higher conductivity than the C11 thiol SAM. More importantly, analysis of the molecular electronic decay constant (beta) exhibits a decrease of at least 15% as compared to purely organic molecular analogues. Hence, the transport characteristics of molecules can be significantly improved for nanoscale electronics through the incorporation of a Ru2 fragment into conjugated backbone.
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Iterative Synthesis of Oligoynes Capped by a Ru2(ap)4-terminus and Their Electrochemical and Optoelectronic Properties. Organometallics 2005. [DOI: 10.1021/om050171i] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Covalent Modification of Diruthenium Alkynyl Compounds: Novel Application of Click Reactions in Organometallic Chemistry. Organometallics 2005. [DOI: 10.1021/om0501632] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Attenuation of acute lung injury in mice by oxymatrine is associated with inhibition of phosphorylated p38 mitogen-activated protein kinase. JOURNAL OF ETHNOPHARMACOLOGY 2005; 98:177-83. [PMID: 15763380 PMCID: PMC7125571 DOI: 10.1016/j.jep.2005.01.026] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2004] [Revised: 12/23/2004] [Accepted: 01/14/2005] [Indexed: 05/22/2023]
Abstract
Oxymatrine is one of the alkaloids extracted from Chinese herb Sophora japonica (Sophora flavescens Ait.) with activities of anti-inflammation, inhibiting immune reaction, antivirus, protecting hepatocytes and antihepatic fibrosis. However, the effect of oxymatrine on acute lung injury (ALI) has not been known yet. In this study, the effect of oxymatrine on ALI was investigated using an oleic acid-induced ALI mouse model. Morphological findings showed that the oleic acid group demonstrated a marked lung injury represented by prominent atelectasis, intraalveolar and interstitial patchy hemorrhage, edema, thickened alveolar septum, formation of hyaline membranes and the existence of inflammatory cells in alveolar spaces. While in the oxymatrine/dexamethasone group, these changes were less severe and in the vicinity of the control group. Furthermore, pretreatment with oxymatrine significantly alleviated oleic acid-induced lung injury accompanied by reduction of lung index and wet-to-dry weight ratio, decreases in serum TNF-alpha level and inhibition of phosphorylated p38 MAPK. These findings suggest that oxymatrine has a beneficial effect on acute lung injury induced by oleic acid in mice and may inhibit the production of proinflammatory cytokine, TNF-alpha, by means of the inhibition of p38 MAPK.
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Sulfide-capped wire-like metallaynes as connectors for Au nanoparticle assemblies. Chem Commun (Camb) 2005:357-9. [PMID: 15645036 DOI: 10.1039/b412336k] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new series of Ru2(DMBA)4(oligo(phenyleneethyne))2 compounds bearing sulfide termini was synthesized; structural characterization revealed both the rigid rod nature and extended pi-conjugation in these metallaynes; in the presence of these metallaynes, Au nanoparticles readily assembled into dimers and chains with well-defined inter-dimer distances.
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Dirhenium Paddlewheel Compounds Supported by N,N‘-Dialkylbenzamidinates: Synthesis, Structures, and Photophysical Properties. Inorg Chem 2004; 43:7887-92. [PMID: 15554655 DOI: 10.1021/ic0487981] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dirhenium(III,III) compounds Re2(DMBA)4Cl2 (1, DMBA=N,N'-dimethylbenzamidinate) and Re2(DEBA)4Cl2 (2, DEBA=N,N'-diethylbenzamidinate) were synthesized via molten reactions between Re2(OAc)4Cl2 and the corresponding amidine. Re2(DMBA)4(NO3)2 (3) was obtained through reacting Re2(DMBA)4Cl2 with AgNO3. Single crystal X-ray diffraction studies revealed that the Re-Re distances in compounds 1-3 are 2.212(1), 2.217(1), and 2.173(1) A, respectively, which are consistent with the presence of a Re-Re quadruple bond. Voltammetric studies revealed that compound 2 exhibits two quasireversible couples, an oxidation and a reduction, and an irreversible reduction, while compound 1 displays irreversible couples at similar potentials. The three complexes exhibit 1deltadelta* absorption as a shoulder at approximately 440 nm (epsilon approximately 1500 M(-1) cm(-1)). Upon excitation of solid samples or CH2Cl2 solutions of 2 with visible light, emission is observed at 824 nm (77 K) and 833 nm (298 K), respectively. The luminescence is assigned as arising from the 3deltadelta* excited state.
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trans-Bis(alkynyl) Diruthenium(III) Tetra(amidinate): An Effective Facilitator of Electronic Delocalization. J Am Chem Soc 2004; 126:3728-9. [PMID: 15038722 DOI: 10.1021/ja049915u] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Insertion of a Ru2(DMBA) unit into 1,4-bisferrocenylbutadiyne drastically enhances the electronic coupling between two Fc units.
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Synthesis and structural characterization of a novel diosmium(III) compound: Os2(ap)4Cl2. Inorganica Chim Acta 2004. [DOI: 10.1016/j.ica.2003.09.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Further studies of tetrakis(N,N′-dialkylbenzamidinato)diruthenium(III) chloro and alkynyl compounds: molecular engineering of metallayne monomers. J Organomet Chem 2003. [DOI: 10.1016/j.jorganchem.2003.08.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Bis-Adducts of Substituted Phenylethynyl on a Ru2(DMBA)4 Core: Effect of Donor/Acceptor Modifications. Organometallics 2003. [DOI: 10.1021/om030401y] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Polyyn-diyls capped by diruthenium termini: a new family of carbon-rich organometallic compounds and distance-dependent electronic coupling therein. J Am Chem Soc 2003; 125:10057-65. [PMID: 12914469 DOI: 10.1021/ja035434j] [Citation(s) in RCA: 172] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Polyyn-diyls capped by Ru(2)(ap)(4) termini (ap = 2-anilinopyridinate), that is, [Ru2(ap)4](mu-C,C'-C2m)[Ru2(ap)4] (compounds 1-5 with m = 1-4 and 6), were synthesized through either a metathesis reaction between Ru2(ap)4Cl and LiC(2m)Li or a Glaser homocoupling reaction of Ru2(ap)4(CmH) under Eglinton/Hay conditions. X-ray diffraction studies of compounds 2 and 4 revealed both the linear rigid rod topology of these compounds and the fine structural details about the Ru2 cores and polyyn-diyl chains. Cyclic and differential pulse voltammetric (CV and DPV) measurements and spectroelectrochemical studies show that reduced and oxidized forms of 1, 2, 4, and 5 are donor-acceptor systems in which the Ru2 termini are coupled to varying degrees depending upon the length of the polyyn-diyl bridge.
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Ru2(DMBA)4(BF4)2 and Ru2(DMBA)4(NO3)2: the first examples of diruthenium compounds containing BF4− and NO3− as ligands. Inorganica Chim Acta 2003. [DOI: 10.1016/s0020-1693(02)01262-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
Complementary sets of genes are epigenetically silenced in male and female gametes in a process termed genomic imprinting. The Dnmt3L gene is expressed during gametogenesis at stages where genomic imprints are established. Targeted disruption of Dnmt3L caused azoospermia in homozygous males, and heterozygous progeny of homozygous females died before midgestation. Bisulfite genomic sequencing of DNA from oocytes and embryos showed that removal of Dnmt3L prevented methylation of sequences that are normally maternally methylated. The defect was specific to imprinted regions, and global genome methylation levels were not affected. Lack of maternal methylation imprints in heterozygous embryos derived from homozygous mutant oocytes caused biallelic expression of genes that are normally expressed only from the allele of paternal origin. The key catalytic motifs characteristic of DNA cytosine methyltransferases have been lost from Dnmt3L, and the protein is more likely to act as a regulator of imprint establishment than as a DNA methyltransferase.
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[The research on processing method of infrared thermography for diabetes]. ZHONGGUO YI LIAO QI XIE ZA ZHI = CHINESE JOURNAL OF MEDICAL INSTRUMENTATION 2000; 24:330-332. [PMID: 12583253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The article shows the author's exploratory opinion about the processing method of infrared thermography for the diagnosis of diabetes.
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[Human physiological regulation in the closed suit with no ventilation]. HANG TIAN YI XUE YU YI XUE GONG CHENG = SPACE MEDICINE & MEDICAL ENGINEERING 2000; 13:332-5. [PMID: 11894870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Objective. To study the effects of the Experimental Closed Suit (ECS) with no active ventilation on human physiological functions and its anti-asphyxic role. Method. Five young healthy male subjects, aged 18-21 years, were tested in the ECS with no active ventilation and no oxygen supply (NAVANOS) when the gas regulatory valve switch was placed on A or B position respectively. Result. (1) Under 1 atm air pressure, each subject could endure at least 15 min while they were aware and resting in the ECS with NAVANOS; (2) There was a balancing period or plateau of the oxygen and the carbon dioxide pressure in the vicinity of the mouth in 5 to 7 min after the sealed helmet was closed, and this period lasted to the end of each test; (3) During the 8-10 min balancing period, the oxygen partial pressure in the vicinity of the mouth ranged from 15.0 to 16.4 kpa, which was slightly hypoxic, and the range of the carbon dioxide partial pressure was 5.21 to 6.49 kPa, which was within the CO2 concentration-time curve of human physiological endurance; (4) No significant difference in human physiological parameters was found when the regulatory valve was placed on A or B position. Conclusion. The anti-asphyxic time of ECS with NAVANOS could at least last 15 min under 1 atm air pressure while the subjects were aware and resting.
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Selenium supplementation of children in a selenium-deficient area in China: blood selenium levels and glutathione peroxidase activities. Biol Trace Elem Res 2000; 73:113-25. [PMID: 11049204 DOI: 10.1385/bter:73:2:113] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/1999] [Accepted: 05/11/1999] [Indexed: 11/11/2022]
Abstract
Keshan disease is a cardiomyopathy restricted to the endemic areas of China and seen in residents having an extremely low selenium (Se) status. Prophylactic administration of sodium selenite has been shown to decrease significantly the incidence of acute and subacute cases. The aim offthe study was to assess the relative bioavailability of selenite versus organic Se-yeast in a Se-deficient area in China with a randomized double-blind double-dummy design. Healthy children (n=30) between 14 and 16 yr of age were randomized into three equal groups receiving either 200 microg/d selenite Se or 200 microg/d Se-yeast or placebo for 12 wk. Blood was drawn at baseline, 4, 8, and 12 wk and 4 wk postsupplementation. The plasma Se concentration (mean +/- SD) was 0.16+/-0.03 micromol/L at baseline. Selenite and Se-yeast supplementation increased plasma Se to plateau values, 1.0+/-0.2 and 1.3+/-0.2 micromol/L, respectively. In red cells, Se-yeast increased the selenium level sixfold and selenite threefold compared to placebo. The relative bioavailability of Se-yeast versus selenite measured as glutathione peroxidase (GSHPx) activity was similar in plasma, red blood cells, and platelets. GSHPx activity reached maximal levels in plasma and platelets of 300% and 200%, respectively, after 8 wk compared to the placebo group, but continued to increase in red cells for 16 wk. Our study showed that although both forms of Se were equally effective in raising GSHPx activity, Se-yeast provided a longer lasting body pool of Se. Se-yeast may be a better alternative to selenite in the prophylaxis of Keshan disease with respect to building up of body stores.
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Chromosome instability and immunodeficiency syndrome caused by mutations in a DNA methyltransferase gene. Nature 1999; 402:187-91. [PMID: 10647011 DOI: 10.1038/46052] [Citation(s) in RCA: 650] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The recessive autosomal disorder known as ICF syndrome (for immunodeficiency, centromere instability and facial anomalies; Mendelian Inheritance in Man number 242860) is characterized by variable reductions in serum immunoglobulin levels which cause most ICF patients to succumb to infectious diseases before adulthood. Mild facial anomalies include hypertelorism, low-set ears, epicanthal folds and macroglossia. The cytogenetic abnormalities in lymphocytes are exuberant: juxtacentromeric heterochromatin is greatly elongated and thread-like in metaphase chromosomes, which is associated with the formation of complex multiradiate chromosomes. The same juxtacentromeric regions are subject to persistent interphase self-associations and are extruded into nuclear blebs or micronuclei. Abnormalities are largely confined to tracts of classical satellites 2 and 3 at juxtacentromeric regions of chromosomes 1, 9 and 16. Classical satellite DNA is normally heavily methylated at cytosine residues, but in ICF syndrome it is almost completely unmethylated in all tissues. ICF syndrome is the only genetic disorder known to involve constitutive abnormalities of genomic methylation patterns. Here we show that five unrelated ICF patients have mutations in both alleles of the gene that encodes DNA methyltransferase 3B (refs 5, 6). Cytosine methylation is essential for the organization and stabilization of a specific type of heterochromatin, and this methylation appears to be carried out by an enzyme specialized for the purpose.
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Further investigation on the role of selenium deficiency in the aetiology and pathogenesis of Keshan disease. BIOMEDICAL AND ENVIRONMENTAL SCIENCES : BES 1997; 10:316-326. [PMID: 9315325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Selenium supplements were not able to restore the ultrastructural changes in the myocardium of latent Keshan disease patients taken by using cardiac catheter endomyocardial biopsy. Observations on the changes of selenium status and the incidence of Keshan disease showed that new latent and naturally-occurring chronic cases were found in the endemic area even after selenium levels had been elevated in the residents to the levels typical in the non-endemic area. These results indicate that although selenium deficiency might be a primary pathogenetic geogen in the occurrence of Keshan disease, it is rather a conditional predisposing factor than a specific or initiative aetiologic factor for the occurrence of Keshan disease. Selenium supplementation could apparently alleviate the higher platelet responsiveness of residents in the endemic area, which might contribute to eliminating the basis for the occurrence of the multifocal perivascular necroses in myocardium of acute and subacute Keshan disease.
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Spliced leader RNA of trypanosomes: in vivo mutational analysis reveals extensive and distinct requirements for trans splicing and cap4 formation. EMBO J 1996; 15:4380-91. [PMID: 8861965 PMCID: PMC452162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
In trypanosomes mRNAs are generated through trans splicing. The spliced leader (SL) RNA, which donates the 5'-terminal mini-exon to each of the protein coding exons, plays a central role in the trans splicing process. We have established in vivo assays to study in detail trans splicing, cap4 modification, and RNP assembly of the SL RNA in the trypanosomatid species Leptomonas seymouri. First, we found that extensive sequences within the mini-exon are required for SL RNA function in vivo, although a conserved length of 39 nt is not essential. In contrast, the intron sequence appears to be surprisingly tolerant to mutation; only the stem-loop II structure is indispensable. The asymmetry of the sequence requirements in the stem I region suggests that this domain may exist in different functional conformations. Second, distinct mini-exon sequences outside the modification site are important for efficient cap4 formation. Third, all SL RNA mutations tested allowed core RNP assembly, suggesting flexible requirements for core protein binding. In sum, the results of our mutational analysis provide evidence for a discrete domain structure of the SL RNA and help to explain the strong phylogenetic conservation of the mini-exon sequence and of the overall SL RNA secondary structure; they also suggest that there may be certain differences between trans splicing in nematodes and trypanosomes. This approach provides a basis for studying RNA-RNA interactions in the trans spliceosome.
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Spliced leader-associated RNA of trypanosomes. Sequence conservation and association with protein components common to trans-spliceosomal ribonucleoproteins. J Biol Chem 1994; 269:30620-5. [PMID: 7982982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
A spliced leader-associated (SLA) RNA recently identified in Trypanosoma brucei has been proposed as a U5 RNA analog in trans-splicing, based on in vivo psoralen cross-linking to the spliced leader (SL) RNA and a short stretch of homology to a conserved U5 RNA sequence. Here we show that the SLA RNA is in the form of an RNP containing common proteins that also occur in the known trans-spliceosomal snRNPs of T. brucei, the SL, U2, and U4/U6 snRNPs. Therefore the SLA RNP is a member of a larger family of related RNPs. The immunoprecipitation of the SLA RNA by antibodies against common proteins does not require an association between the SLA RNA and the SL RNP. To identify sequences of potential functional importance and to establish a secondary structure model, we have sequenced the SLA RNA and cloned its gene from a related trypanosomatid, Leptomonas seymouri. A sequence comparison between the T. brucei and L. seymouri SLA RNAs reveals that the U5-homologous sequence element is not conserved.
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Spliced leader-associated RNA of trypanosomes. Sequence conservation and association with protein components common to trans-spliceosomal ribonucleoproteins. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)43859-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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trans-spliceosomal U6 RNAs of Crithidia fasciculata and Leptomonas seymouri: deviation from the conserved ACAGAG sequence and potential base pairing with spliced leader RNA. Mol Cell Biol 1994; 14:4565-70. [PMID: 8007960 PMCID: PMC358828 DOI: 10.1128/mcb.14.7.4565-4570.1994] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
U6 RNA genes from the trypanosomatids Crithidia fasciculata and Leptomonas seymouri have been isolated and sequenced. As in Trypanosoma brucei, the U6 RNA genes in both C. fasciculata and L. seymouri are arranged in close linkage with upstream tRNA genes. The U6 RNA sequences from C. fasciculata and L. seymouri deviate in five and three positions, respectively, from the published T. brucei sequence. Interestingly, both C. fasciculata U6 RNA genes carry a C-->T change at the second position of the ACAGAG hexanucleotide sequence, which is important for splicing function and has been considered phylogenetically invariable. A compensatory base change of the C. fasciculata spliced leader RNA at the highly conserved 5' splice site position +5, G-->A, suggests that an interaction between the 5' splice site region and U6 RNA recently proposed for the yeast cis-splicing system may also occur in trans splicing.
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Comparison of Shams' test for rectal mucus to an immunological test for fecal occult blood in large intestinal carcinoma screening. Analysis of a check-up of 6480 asymptomatic subjects. Chin Med J (Engl) 1993; 106:739-42. [PMID: 8033605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The sugar moiety detected from rectal mucus by the Galactose oxidase-schiff (Shams' test) is considered a substitutive test for immunological fecal occult blood test (FOBT) in screening colorectal carcinoma. Two strategies of screening were applied in 6480 subjects over 40 years of age, and 130 cm flexible colonoscope used for sigmoidoscopy or pancolonoscopy. Of them, 3820 were taken for immune FOBT (SPA test) and Shams' test. Only those who showed positive tests were chosen for 60 cm flexible sigmoidoscopy, while another 2660 subjects for both sigmoidoscopy and tests at the same time. Additionally, 130 cm flexible pancolonoscopy was carried out in 103 individuals with positive Shams' test for evaluating the false positive rate. Shams' test showed a sensitivity of 85.7% for colorectal cancer, 47.1% for adenomas in preselected patients, while the positive rate of SPA test were 90.5% and 41.2% respectively. In 3820 asymptomatic subjects undergoing sequential screening (aged 45 years and higher), Shams' test showed 9.1% positive, SPA showed 11.2% and 620 (16.2%) subjects were selected for sigmoidoscopy based on their positive galactose oxidase result or positive FOBT result. Two early stage carcinomas and 33 adenomas (0.32% and 4.2% respectively in sigmoidoscopy) were found. Another 2 660 subjects were taken for sigmoidoscopy screening. Four carcinomas and 78 adenomas were found. Of them, only two carcinoma (50%) and 17 (21.8%) or 22 (28.2%) adenomas were positive in Shams' or SPA test. But both tests combined in screening showed a rate of 61.3% in adenomas and 75.0% in cancers. 103 subjects with positive Shams' test were taken for pancolonoscopy. 82.5% showed no lesions.(ABSTRACT TRUNCATED AT 250 WORDS)
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Effects of selenium deficiency on Ca transport function of sarcoplasmic reticulum and lipid peroxidation in rat myocardium. Biol Trace Elem Res 1993; 36:159-66. [PMID: 7681308 DOI: 10.1007/bf02783175] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Two groups of weanling Sprague-Dawley rats were fed a low-selenium basal diet (Se 0.009 mg/kg) and the same diet supplemented with sodium selenite (Se 0.25 mg/kg), respectively, for 1, 2, and 3 months. At each feeding time, the Ca(2+)-ATPase activity, Ca2+ uptake rate and the capacity of Ca2+ uptake in isolated cardiac sacroplasmic reticulum from the Se-deficient rats were decreased significantly compared to those from the Se-supplemented rats, the contents of lipid peroxide in postmitochondrial supernatant and isolated sarcoplasmic reticulum from the Se-deficient rats were significantly higher than that from Se-supplemented rats. Compared to the Se-supplemented rats, the cytosolic glutathione peroxidase activity in Se-deficient rats decreased significantly. In addition, significant linear negative correlations of lipid peroxide in postmitochondrial supernatant to sarcoplasmic reticular Ca(2+)-ATPase activity, Ca2+ uptake rate and to whole blood selenium concentration were observed. The results suggest that the enhancement of lipid peroxidation via the depressed glutathione peroxidase activity might be responsible for the decrease of Ca(2+)-ATPase and Ca2+ uptake activities in sarcoplasmic reticulum in Se-deficient animals.
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BsuBI--an isospecific restriction and modification system of PstI: characterization of the BsuBI genes and enzymes. Nucleic Acids Res 1992; 20:6517-23. [PMID: 1480472 PMCID: PMC334566 DOI: 10.1093/nar/20.24.6517] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The enzymes of the Bacillus subtilis BsuBI restriction/modification (R/M) system recognize the target sequence 5'CTGCAG. The genes of the BsuBI R/M system have been cloned and sequenced and their products have been characterized following overexpression and purification. The gene of the BsuBI DNA methyltransferase (M.BsuBI) consists of 1503 bp, encoding a protein of 501 amino acids with a calculated M(r) of 57.2 kD. The gene of the restriction endonuclease (R.BsuBI), comprising 948 bp, codes for a protein of 316 amino acids with a predicted M(r) of 36.2 kD. M.BsuBI modifies the adenine (A) residue of the BsuBI target site, thus representing the first A-N6-DNA methyltransferase identified in B. subtilis. Like R.PstI, R.BsuBI cleaves between the A residue and the 3' terminal G of the target site. Both enzymes of the BsuBI R/M system are, therefore, functionally identical with those of the PstI R/M system, encoded by the Gram negative species Providencia stuartii. This functional equivalence coincides with a pronounced similarity of the BsuBI/PstI DNA methyltransferases (41% amino acid identity) and restriction endonucleases (46% amino acid identity). Since the genes are also very similar (58% nucleotide identity), the BsuBI and PstI R/M systems apparently have a common evolutionary origin. In spite of the sequence conservation the gene organization is strikingly different in the two R/M systems. While the genes of the PstI R/M system are separated and transcribed divergently, the genes of the BsuBI R/M system are transcribed in the same direction, with the 3' end of the M gene overlapping the 5' end of the R gene by 17 bp.
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Effects of selenium on ribonucleic acid synthesis and degradation in rat liver. JOURNAL OF TRACE ELEMENTS AND ELECTROLYTES IN HEALTH AND DISEASE 1992; 6:161-7. [PMID: 1282838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Six groups of weanling rats were fed a low-selenium based diet containing less than 0.01 mg/kg of Se in the diet or the basal diet supplemented with five levels of selenium as selenite (0.1, 0.2, 0.3, 0.4 and 0.5 mg/kg) for at least 16 to 18 weeks. For determination of the effect of selenium on ribonucleic acid (RNA) synthesis in rat liver, rats of each dietary group were injected with a single dose of (5-3H)-uridine, and 3 hours later their livers were removed and subjected to cell fractionation. The radioactivities in the nuclear and cytoplasmic RNA were taken as a measure of the RNA synthesis rate. With selenium supplementation between 0.2 and 0.5 mg/kg diet, the radioactivities, amounts of RNA, as well as RNA/DNA ratios in both nuclear and cytoplasmic fractions of rat liver all increased significantly. In addition, at similar levels of selenium supplementation, statistically significant increments of glutathione peroxidase (GSH-Px) activity and reductions in lipid peroxide in liver were also observed. For assessment of RNA degradation, activities of ribonucleases (RNase) and RNase inhibitor in rats fed the low-selenium diet or a selenium-supplemented diet were determined. The activities of acid RNase and both free and latent alkaline RNase in liver homogenate were not affected by selenium deficiency; however, the level of RNase inhibitor present in the supernatant fraction increased significantly with selenium supplementation at 0.2 mg/kg diet.(ABSTRACT TRUNCATED AT 250 WORDS)
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Fatty acid composition of blood lipids in Chinese children consuming high erucic acid rapeseed oil. ANNALS OF NUTRITION & METABOLISM 1992; 36:273-8. [PMID: 1492753 DOI: 10.1159/000177729] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The fatty acid patterns of oils, blood plasma and erythrocyte lipids from 28 children in the Shaanxi province of the People's Republic of China were determined by capillary gas liquid chromatography. The main source of fat in this region is rapeseed oil. The analysis of locally available rapeseed oil shows a high erucic acid content (mean 43.83%, range 33.91-50.48%). According to protocol data, about 3% of the daily nutrient energy is provided by erucic acid. Despite a low fat intake in Chinese children, the composition of the fatty acids of the fractions analyzed showed normal patterns. However, erucic acid was found in all fractions analyzed. Data on erucic acid in human tissue are scarce. Although there are no indications of erucic acid toxicity in man, it is known to cause cardiac lipidosis and necrosis in rats. The question remains open if erucic acid aggravates selenium deficiency symptoms which are known to be associated with Keshan disease, an endemic cardiomyopathy.
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[Investigation of human cytomegalovirus infection in 103 cases with history of abnormal pregnancy]. ZHONGHUA FU CHAN KE ZA ZHI 1991; 26:272-4, 322. [PMID: 1657549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Human cytomegalovirus (HCMV)-IgG, IgM antibodies were detected by indirect ELISA in 103 serum specimens from women with history of abnormal pregnancy. The results showed that the positive rates of HCMV-IgG and IgM of abnormal pregnant women were 90.29% and 13.59% respectively. The positive rate of HCMV-IgM in abnormal pregnancies was higher than that of normal pregnancies (4.07%, P less than 0.001). This suggested that the probability of abnormal pregnancy in HCMV-IgM positive women was higher than the negative ones. Thus detecting HCMV-IgM by ELISA could be used not only in early diagnosis of active HCMV infection in pregnant women, but also a way to prevent this delivery of malformed babies.
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