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51.
This research used a nationally representative sample of 12,756 respondents self-identified as White, Black, Hispanic, or Asian to examine problem drinking in relationship to social structure and mental healthcare factors. Associations between problem drinking and particular factors varied by racial/ethnic group. Results also indicated that Whites’ problem-drinking rates were higher than those of Hispanics, Blacks, and Asians. Americans sometimes use alcohol to manage stress stemming from social disadvantage and inadequate material resources. Across racial/ethnic groups, drinking level was associated with the type and degree of such disadvantage. Additionally, the presence of a mental health problem was associated with problem drinking. 相似文献
52.
Polydopamine (PD) is a synthetic melanin analogue of growing importance in the field of biomedicine, especially with respect to cancer research, due, in part, to its biocompatibility. But little is known about the cytotoxic effects of PD on cancer cell lines. PD is a UV-vis absorbing material whose absorbance overlaps with that of formazan salts, which are used to assess cell viability in MTT assays. In this study, a protocol has been established to eliminate the contributing absorbance of PD at 550 nm, and has been applied to characterize the cytotoxicity of PD nanoparticles in both healthy and breast cancer cell lines. Once the protocol is applied, it was found that PD is per se an antineoplastic system, meaning it selectively kills cancer cells, especially those of breast cancer, but it has no toxic effect on healthy cells. The mechanism of action could be related to the production of ROS and the alteration of iron homeostasis in lysosomes. To the best of our knowledge there are only a few examples of nanoparticle systems devoid of drugs that selectively kill cancer cells.Polydopamine (PD) is a synthetic melanin analogue of growing importance in the field of biomedicine, especially with respect to cancer research, due, in part, to its biocompatibility. 相似文献
53.
Kenichi Tsujita MD PhD Akiko Maehara MD Gary S. Mintz MD Hiroshi Doi MD PhD Takashi Kubo MD PhD Celia Castellanos MD Jian Liu MD Junqing Yang MD Carlos Oviedo MD Theresa Franklin-Bond MS PA Neil Dasgupta MA Sinan Biro BS Lokesh Dani BA George D. Dangas MD PhD Roxana Mehran MD Ajay J. Kirtane MD Alexandra J. Lansky MD Edward M. Kreps MD Michael B. Collins MD Gregg W. Stone MD Jeffrey W. Moses MD Martin B. Leon MD 《The American journal of cardiology》2008,102(12):1608-1613
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Absolute requirement of spermidine for growth and cell cycle progression of fission yeast (Schizosaccharomyces pombe) 下载免费PDF全文
Chattopadhyay MK Tabor CW Tabor H 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(16):10330-10334
Schizosaccharomyces pombe cells that cannot synthesize spermidine or spermine because of a deletion-insertion in the gene coding for S-adenosylmethionine decarboxylase (Deltaspe2) have an absolute requirement for spermidine for growth. Flow cytometry studies show that in the absence of spermidine an overall delay of the cell cycle progression occurs with some accumulation of cells in the G(1) phase; as little as 10(-6) M spermidine is sufficient to maintain normal cell cycle distribution and normal growth. Morphologically some of the spermidine-deprived cells become spherical at an early stage with little evidence of cell division. On further incubation in the spermidine-deprived medium, growth occurs in most of the cells, not by cell division but rather by cell elongation, with an abnormal distribution of the actin cytoskeleton, DNA (4', 6-diamidino-2-phenylindole staining), and calcofluor-staining moieties. More prolonged incubation in the spermidine-deficient medium leads to profound morphological changes including nuclear degeneration. 相似文献
56.
Stephen Holland Celia Kitzinger Jenny Kitzinger 《Medicine, health care, and philosophy》2014,17(3):413-423
Some brain injured patients are left in a permanent vegetative state, i.e., they have irreversibly lost their capacity for consciousness but retained some autonomic physiological functions, such as breathing unaided. Having discussed the controversial nature of the permanent vegetative state as a diagnostic category, we turn to the question of the patients’ ontological status. Are the permanently vegetative alive, dead, or in some other state? We present empirical data from interviews with relatives of patients, and with experts, to support the view that the ontological state of permanently vegetative patients is unclear: such patients are neither straightforwardly alive nor simply dead. Having defended this view from counter-arguments we turn to the practical question as to how these patients ought to be treated. Some relatives and experts believe it is right for patients to be shifted from their currently unclear ontological state to that of being straightforwardly dead, but many are concerned or even horrified by the only legally sanctioned method guaranteed to achieve this, namely withdrawal of clinically assisted nutrition and hydration. A way of addressing this distress would be to allow active euthanasia for these patients. This is highly controversial; but we argue that standard objections to allowing active euthanasia for this particular class of permanently vegetative patients are weakened by these patients’ distinctive ontological status. 相似文献
57.
Background
The incidence of postoperative urinary retention (PUR) has been reported to range from 1% to 22% in patients who have undergone laparoscopic inguinal hernia procedures. The objectives of this study were to determine the incidence of PUR and examine different risk factors that may be associated with the development of PUR in patients who have undergone laparoscopic inguinal hernia procedures.Methods
A retrospective chart review was performed on 350 patients. Demographics, comorbidities, and operative and postoperative information were collected in patients undergoing laparoscopic inguinal hernia repair by 3 general surgeons from 2007 to 2011. Statistical analysis was done on patient demographics, medical histories, anesthesia notes, and postoperative notes to identify risk factors for the development of urinary retention after laparoscopic inguinal hernia repair.Results
Three hundred fifty consecutive patients who underwent laparoscopic inguinal hernia repairs were reviewed. Twenty-nine patients developed PUR, an incidence of 8.3%. Age ≥60 years and history of benign prostatic hyperplasia showed significance on multivariate analysis, with odds ratios of 3.0 and 11.0 respectively (P < .05). Anesthesia time ≥2 hours (odds ratio, .75) was a contributing perioperative risk factor but only as an independent risk factor (P < .05).Conclusions
History of benign prostatic hyperplasia, age ≥60 years, and anesthesia time ≥2 hours were significant independent risk factors for urinary retention after laparoscopic inguinal hernia repair. On multivariate analysis, only history of group and age ≥60 years showed significance. This is 1 of the largest studies to show that the development of PUR in laparoscopic inguinal hernia repair patients is a multifactorial process. Further studies should be conducted to corroborate our findings. 相似文献58.
Carl J. Brown Marylise Boutros Andrew Morris Celia M. Divino 《Canadian journal of surgery》2014,57(3):214-216
Objective: To determine whether a colon-sparing diverting ileostomy with colonic lavage reduces mortality in patients with severe Clostridium difficile–associated disease (CDAD) when compared with colectomy. Design: Retrospective cohort study. Setting & patients: Forty-two patients with diagnosed severe, complicated CDAD who were treated at the University of Pittsburgh Medical Center or VA Pittsburgh Health Care System between June 2009 and January 2011 with diverting loop ileostomy and colonic lavage (warmed polyethylene glycol 3350/electrolyte solution via the ileostomy and postoperative antegrade instillation of vancomycin flushes via the ileostomy). Patients were compared with a historical control group of 42 patients who had a colectomy. Main outcome: Resolution of CDAD. Results: There was no significant difference in age, sex, pharmacologic immuno-suppression and Acute Physiology and Chronic Health Evaluation-II (APACHE-II) scores between the current cohort and historical controls. In the ileostomy group, surgery was performed laparoscopically in 35 patients (83%). This treatment strategy resulted in reduced mortality compared with the historical population (19% v. 50%; odds ratio [OR] 0.24, p = 0.006). Preservation of the colon was achieved in 39 of 42 patients (93%). Conclusion: Loop ileostomy and colonic lavage are an alternative to colectomy in the treatment of severe, complicated CDAD, resulting in reduced morbidity and preservation of the colon. 相似文献
59.
60.
Viviane M. Gonçalves Waldely O. Dias Ivana B. Campos Celia Liberman Maria E. Sbrogio-Almeida Eliane P. Silva Celso P. Cardoso Jr. Mark Alderson George Robertson Jean-François Maisonneuve Andrea Tate Porter Anderson Richard Malley Fernando Fratelli Luciana C.C. Leite 《Vaccine》2014
Pneumococcal infections impose a large burden of disease on the human population, mainly in developing countries, and the current pneumococcal vaccines offer serotype-specific protection, but do not cover all pathogenic strains, leaving populations vulnerable to disease caused by non-vaccine serotypes. The pneumococcal whole cell vaccine is a low-cost strategy based on non-capsular antigens common to all strains, inducing serotype-independent immunity. Therefore, we developed the process for the cGMP production of this cellular vaccine. Initially, three engineering runs and two cGMP runs were performed in 60-L bioreactors, demonstrating the consistency of the production process, as evaluated by the growth curves, glucose consumption and metabolite formation (lactate and acetate). Cell recovery by tangential filtration was 92 ± 13%. We optimized the conditions for beta-propiolactone (BPL) inactivation of the bacterial suspensions, establishing a maximum cell density of OD600 between 27 and 30, with a BPL concentration of 1:4000 (v/v) at 150 rpm and 4 °C for 30 h. BPL was hydrolyzed by heating for 2 h at 37 °C. The criteria and methods for quality control were defined using the engineering runs and the cGMP Lots passed all specifications. cGMP vaccine Lots displayed high potency, inducing between 80 and 90% survival in immunized mice when challenged with virulent pneumococci. Sera from mice immunized with the cGMP Lots recognized several pneumococcal proteins in the extract of encapsulated strains by Western blot. The cGMP whole cell antigen bulk and whole cell vaccine product lots were shown to be stable for up to 12 and 18 months, respectively, based upon survival assays following i.p. challenge. Our results show the consistency and stability of the cGMP whole cell pneumococcal vaccine lots and demonstrate the feasibility of production in a developing country setting. 相似文献