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101.
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103.
Effects of skeletal muscle protein phosphatase inhibitor-2 on protein synthesis and protein phosphorylation in rabbit reticulocyte lysates 总被引:4,自引:2,他引:4
Vivian Ernst Daniel H. Levin J. Gordon Foulkes Irving M. London 《Proceedings of the National Academy of Sciences of the United States of America》1982,79(23):7092-7096
Reticulocyte lysates contain two major classes of protein phosphatase activities, designated type 1 and type 2. These designations are based on criteria derived from the analyses of protein phosphatase species in other tissues. The criteria include (i) chromatographic elution profiles on DEAE-cellulose; (ii) specificity of lysate phosphatases toward [(32)P]phosphorylase a and [(32)P]phosphorylase kinase; (iii) sensitivity of lysate phosphatases to Mg(2+) ATP; and (iv) sensitivity to the heat-stable protein phosphatase inhibitor-2. The lysate phosphatase species are similar to those described in rabbit skeletal muscle and rabbit liver. Reticulocyte protein phosphatase type 1, but not type 2, is inhibited by heat-stable protein phosphatase inhibitor-1 and -2 which have been characterized from rabbit skeletal muscle. We have initiated a study on the function and specificity of lysate protein phosphatase activities involved in the regulation of protein synthesis by examining the effects of protein phosphatase inhibitor-2 on reticulocyte protein synthesis and protein phosphorylation. Our findings are as follows. (a) Protein phosphatase inhibitor-2 inhibits protein chain initiation in hemin-supplemented lysates. (b) Inhibition is characterized by biphasic kinetics and is reversed by the delayed addition of purified reticulocyte eukaryotic initiation factor 2 (eIF-2). (c) Inhibition of protein synthesis by inhibitor-2 is accompanied by the phosphorylation of the alpha-subunit (38,000 daltons) of eIF-2 (eIF-2alpha) and of two heat-stable polypeptides of 29,000 and 44,000 daltons. (d) The 29,000-dalton component is phosphorylated in lysates under conditions of protein synthesis and appears to be inhibitor-2, but the physiological significance of this modification of inhibitor-2 is not clear. (e) Inhibitor-2 has no effect on the activation in vitro of isolated heme-regulated or double-stranded RNA-dependent eIF-2alpha kinases. We propose that the inhibition of protein synthesis in hemin-supplemented lysates by added inhibitor-2 is due at least in part to the inhibition of a type 1 eIF-2alpha phosphatase activity, which permits a basal eIF-2alpha kinase activity to be expressed leading to the accumulation of phosphorylated eIF-2alpha and an inhibition of protein synthesis. 相似文献
104.
Kaela M. Varberg Khursheed Iqbal Masanaga Muto Mikaela E. Simon Regan L. Scott Keisuke Kozai Ruhul H. Choudhury John D. Aplin Rebecca Biswell Margaret Gibson Hiroaki Okae Takahiro Arima Jay L. Vivian Elin Grundberg Michael J. Soares 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(10)
105.
Michael G. Usher Christine Fanning Vivian W. Fang Madeline Carroll Amay Parikh Anne Joseph Dana Herrigel 《Journal of general internal medicine》2018,33(12):2078-2084
Background
Patients transferred between hospitals are at high risk of adverse events and mortality. The relationship between insurance status, transfer practices, and outcomes has not been definitively characterized.Objective
To identify the association between insurance coverage and mortality of patients transferred between hospitals.Design
We conducted a single-institution observational study, and validated results using a national administrative database of inter-hospital transfers.Setting
Three ICUs at an academic tertiary care center validated by a nationally representative sample of inter-hospital transfers.Patients
The single-institution analysis included 652 consecutive patients transferred from 57 hospitals between 2011 and 2012. The administrative database included 353,018 patients transferred between 437 hospitals.Measurements
Adjusted inpatient mortality and 24-h mortality, stratified by insurance status.Results
Of 652 consecutive transfers to three ICUs, we observed that uninsured patients had higher adjusted inpatient mortality (OR 2.67, p?=?0.021) when controlling for age, race, gender, Apache-II, and whether the patient was transferred from an ED. Uninsured were more likely to be transferred from ED (OR 2.3, p?=?0.026), and earlier in their hospital course (3.9 vs 2.0 days, p?=?0.002). Using an administrative dataset, we validated these observations, finding that the uninsured had higher adjusted inpatient mortality (OR 1.24, 95% CI 1.13–1.36, p?<?0.001) and higher mortality within 24 h (OR 1.33 95% CI 1.11–1.60, p?<?0.002). The increase in mortality was independent of patient demographics, referral patterns, or diagnoses.Limitations
This is an observational study where transfer appropriateness cannot be directly assessed.Conclusions
Uninsured patients are more likely to be transferred from an ED and have higher mortality. These data suggest factors that drive inter-hospital transfer of uninsured patients have the potential to exacerbate outcome disparities.106.
107.
Adjuvant Therapy With Sodium Alendronate for the Treatment of Experimental Periodontitis in Rats 下载免费PDF全文
Juliano De Almeida Edilson Ervolino Luiz Henrique Bonfietti Vivian Cristina Noronha Novaes Letícia Helena Theodoro Leandro Araujo Fernandes Thiago Marchi Martins Paula Lazilha Faleiros Valdir Gouveia Garcia 《Journal of periodontology》2015,86(10):1166-1175
Background: This study assesses the effects of topical sodium alendronate (SA) as an adjuvant to the mechanical treatment of ligature‐induced periodontitis in rats. Methods: Ninety animals were subjected to the induction of periodontitis via the installation of a ligature around the mandibular left first molar. After 7 days, the ligature was removed, and the animals were distributed into the following groups: 1) NT group (n = 30), no treatment; 2) SRP group (n = 30), scaling and root planing (SRP) and local irrigation with physiologic saline solution; and 3) SRP/SA group (n = 30), SRP and local irrigation with SA (10?5 M). Ten animals from each group were euthanized at 7, 15, and 30 days after treatment. Histologic and histometric analyses were performed in the furcation region. The percentage of bone in the furcation (PBF) was measured. Immunohistochemical analyses for detecting the receptor activator of nuclear factor‐κB ligand (RANKL), osteoprotegerin (OPG), tartrate‐resistant acid phosphatase (TRAP), and activated caspase‐3 were performed at the furcation region. Results: Compared with the other groups, the SRP/SA group showed less local inflammation and better tissue reparation during the entire experiment. There was more PBF in the SRP/SA group than in the other groups at days 7 and 15. Stronger OPG immunolabeling and weaker RANKL immunolabeling were observed in the SRP/SA group at 15 and 30 days. There were fewer TRAP‐positive cells in the SRP/SA group than in the NT group at all of the time points. There was no difference in the number of activated caspase‐3‐positive osteocytes among groups and time points. Conclusion: It can be concluded that topical use of SA as an adjuvant to SRP is effective in the treatment of experimental periodontitis. 相似文献
108.
We describe a case of unrecognized rectal puncture following unsuccessful caudal blockade in a patient later found to have marked rectal distension on MRI. This may have contributed to the rectal injury. 相似文献
109.
Ambar Oyarzábal Yohani Pérez Vivian Molina Rosa Mas Yazmin Ravelo Sonia Jiménez 《Translational andrology and urology》2015,4(4):391-397
Background
Lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia (BPH) mainly depend on alpha1-adrenoreceptors (α1-ADR) stimulation, but a link with oxidative stress (OS) is also involved. D-004, a lipid extract of Roystonea regia fruits, antagonizes ADR-induced responses and produces antioxidant effects. The objective of this study was to investigate whether D-004 produce antioxidant effects in rats with phenylephrine (PHE)-induced urodynamic changes.Methods
Rats were randomized into eight groups (ten rats/group): a negative vehicle control and seven groups injected with PHE: a positive control, three treated with D-004 (200, 400 and 800 mg/kg) and three others with tamsulosin (0.4 mg/kg), grape seed extract (GSE) (250 mg/kg) and vitamin E (VE) (250 mg/kg), respectively.Results
Effects on urinary total volume (UTV), volume voided per micturition (VM), malondialdehyde (MDA) and carbonyl groups (CG) concentrations in prostate and bladder homogenates were study outcomes. While VM and UTV lowered significantly in the positive control as compared to the negative control group, the opposite occurred with prostate and bladder MDA and CG values. D-004 (200-800 mg/kg) increased significantly both VM and UTV, lowered significantly MDA in prostate and bladder homogenates, and reduced GC levels only in the prostate. Tamsulosin increased significantly VM and UTV, but unchanged oxidative variables. GSE and VE unchanged the UTV, whereas VE, not GSE, modestly but significantly attenuated the PHE-induced decrease of VM.Conclusions
Single oral administration of D-004 (200-800 mg/kg) was the only treatment that ameliorated the urodynamic changes and reduced increased oxidative variables in the prostate of rats with PHE-induced prostate hyperplasia. 相似文献110.
Jofré L Perret C Dabanch J Abarca K Olivares R Luchsinger V Aguilera X Sotomayor V Olea A 《Revista chilena de infectología》2005,22(1):75-88
Influenza is a seasonally, acute respiratory disease, highly transmissible. The diversity of the natural reservoirs of influenza A virus and its faculty of reassortment increase the risk of a new pandemia. Prevention strategies during the outbreaks include vaccination indicated to risk population as infants between 6 to 2 years old, persons above 65 years old, pregnant women and patients with underlying diseases. Antiviral prophylaxis is useful to control small outbreaks and to be used in household contacts of risk population who have not been vaccinated. Antiviral drugs as a treatment should be considered in persons with severe disease. During a pandemia these prevention measures must be reinforced and rational use of antiviral drugs and vaccine with the pandemic strain should be emphasized. 相似文献