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81.
Dongeun Yong Mark A. Toleman Jan Bell Brett Ritchie Rachael Pratt Henry Ryley Timothy R. Walsh 《Antimicrobial agents and chemotherapy》2012,56(12):6154-6159
Three clinical Pseudomonas aeruginosa isolates (WCH2677, WCH2813, and WCH2837) isolated from the Women''s and Children''s Hospital, Adelaide, Australia, produced a metallo-β-lactamase (MBL)-positive Etest result. All isolates were PCR negative for known MBL genes. A gene bank was created, and an MBL gene, designated blaAIM-1, was cloned and fully characterized. The encoded enzyme, AIM-1, is a group B3 MBL that has the highest level of identity to THIN-B and L1. It is chromosomal and flanked by two copies (one intact and one truncated) of an ISCR element, ISCR15. Southern hybridization studies indicated the movement of both ISCR15 and blaAIM-1 within the three different clinical isolates. AIM-1 hydrolyzes most β-lactams, with the exception of aztreonam and, to a lesser extent, ceftazidime; however, it possesses significantly higher kcat values for cefepime and carbapenems than most other MBLs. AIM-1 was the first mobile group B3 enzyme detected and signals further problems for already beleaguered antimicrobial regimes to treat serious P. aeruginosa and other Gram-negative infections. 相似文献
82.
The fludarabine,cytarabine, and granulocyte colony‐stimulating factor (FLAG) chemotherapy regimen is an alternative to anthracycline‐based therapy for the treatment of acute myeloid leukemia for patients with pre‐existing cardiac disease 下载免费PDF全文
Lalit Saini Joseph Brandwein Robert Turner Loree Larratt Marlene Hamilton Anthea Peters Cynthia Wu Nancy Zhu Jeffery M. Patterson Lauren Bolster Michael Mant Bruce Ritchie Elena Liew Sunita Ghosh Irwindeep Sandhu 《European journal of haematology》2016,97(5):471-478
We conducted a retrospective study assessing FLAG (fludarabine, cytarabine, and granulocyte colony‐stimulating factor) as first‐line treatment in 56 newly diagnosed acute myeloid leukemia patients considered ineligible for anthracycline‐based treatment due to advanced age, significant comorbidities, or pre‐existing cardiac disease. The median age was 69 (21–80); 46% received FLAG for pre‐existing cardiac disease and others due to age (32%), non‐cardiac comorbidities (20%), or previous anthracycline exposure (2%). The induction mortality was 16% and, among evaluable patients, 48% achieved a complete remission after the first induction course with an additional patient achieving a remission after a second course for a total complete remission rate of 50%. Four patients proceeded to an allogeneic stem cell transplant including two with pre‐existing cardiac disease. Among non‐transplanted patients, the relapse rate (RR) was 47%. When censored at time of stem cell transplant, the median relapse‐free survival was 14.7 months. The median overall survival was 9.3 months with 1‐ and 2‐yr survivals of 44% and 22%, respectively. There was no difference in clinical outcomes between patients treated with FLAG for cardiac reasons vs. other reasons. In conclusion, FLAG is a useful alternative to anthracycline‐based induction for Acute myeloid leukemia in those with significant comorbidities including pre‐existing cardiac disease. 相似文献
83.
Joanne M. Pohl PhD RN CS Charles W. Given PhD Clare E. Collins PhD RN FAAN Barbara A. Given PhD RN FAAN 《Health care for women international》2013,34(5):385-395
Variables that have been conceptually linked with social vulnerability—income, educational level, employment, cessation of work to provide care, marital status, social support, and health—were used to predict four categories of reaction to caregiving in 159 daughters and daughters‐in‐law caring for their disabled aging parents. Social support, income, and health best predicted negative reactions to caregiving; social support alone best predicted feelings of family abandonment, impact on health, and impact on schedule. Compared with daughters and daughters‐in‐law who had not quit work to provide care, those who had quit work were significantly older, had lower incomes and fewer social supports, and were more involved in care. The results suggest that quitting work may be a precursor to social isolation that places the caregiver at increased risk for social vulnerability and negative reaction to caregiving. The implications of the findings for health care policy are discussed. 相似文献
84.
85.
Erin S Calipari Mark J Ferris Benjamin A Zimmer David CS Roberts Sara R Jones 《Neuropsychopharmacology》2013,38(12):2385-2392
The dopamine transporter (DAT) is responsible for terminating dopamine (DA) signaling and is the primary site of cocaine''s reinforcing actions. Cocaine self-administration has been shown previously to result in changes in cocaine potency at the DAT. To determine whether the DAT changes associated with self-administration are due to differences in intake levels or temporal patterns of cocaine-induced DAT inhibition, we manipulated cocaine access to produce either continuous or intermittent elevations in cocaine brain levels. Long-access (LgA, 6 h) and short-access (ShA, 2 h) continuous self-administration produced similar temporal profiles of cocaine intake that were sustained throughout the session; however, LgA had greater intake. ShA and intermittent-access (IntA, 6 h) produced the same intake, but different temporal profiles, with ‘spiking'' brain levels in IntA compared with constant levels in ShA. IntA consisted of 5-min access periods alternating with 25-min timeouts, which resulted in bursts of high responding followed by periods of no responding. DA release and uptake, as well as the potency of cocaine for DAT inhibition, were assessed by voltammetry in the nucleus accumbens slices following control, IntA, ShA, and LgA self-administration. Continuous-access protocols (LgA and ShA) did not change DA parameters, but the ‘spiking'' protocol (IntA) increased both release and uptake of DA. In addition, high continuous intake (LgA) produced tolerance to cocaine, while ‘spiking'' (IntA) produced sensitization, relative to ShA and naive controls. Thus, intake and pattern can both influence cocaine potency, and tolerance seems to be produced by high intake, while sensitization is produced by intermittent temporal patterns of intake. 相似文献
86.
87.
Shanti Raman Krishnamachari Srinivasan Anura Kurpad Jan Ritchie Husna Razee 《Health care for women international》2016,37(10):1119-1137
The limited autonomy and agency of women in developing countries is recognized as a key barrier to improving their reproductive health. Using an existing perinatal cohort in urban South India, we interviewed 36 women who had recently been through childbirth, and we carried out observations of family life and clinic encounters. Critical domains involved in women's agency and autonomy were women's participation in employment and group action and their mobility. Household decision making was considered a joint rather than individual responsibility. We call for a more nuanced understanding of these domains and their relationship to women's reproductive health, particularly for urban populations. 相似文献
88.
Abigail B. Diack Diane Ritchie Matthew Bishop Victoria Pinion Jean-Philippe Brandel Stephane Haik Fabrizio Tagliavini Cornelia Van Duijn Ermias D. Belay Pierluigi Gambetti Lawrence B. Schonberger Pedro Piccardo Robert G. Will Jean C. Manson 《Emerging infectious diseases》2012,18(10):1574-1579
Variant Creutzfeldt-Jakob disease (vCJD) has been reported in 12 countries. We hypothesized that a common strain of agent is responsible for all vCJD cases, regardless of geographic origin. To test this hypothesis, we inoculated strain-typing panels of wild-type mice with brain material from human vCJD case-patients from France, the Netherlands, Italy, and the United States. Mice were assessed for clinical disease, neuropathologic changes, and glycoform profile; results were compared with those for 2 reference vCJD cases from the United Kingdom. Transmission to mice occurred from each sample tested, and data were similar between non-UK and UK cases, with the exception of the ranking of mean clinical incubation times of mouse lines. These findings support the hypothesis that a single strain of infectious agent is responsible for all vCJD infections. However, differences in incubation times require further subpassage in mice to establish any true differences in strain properties between cases. 相似文献
89.
The relationship between sex role identity and depression in nurses was explored. It was posited that nurses tend to be high in feminine traits and have traditional attitudes and that these traits and attitudes will be correlated with depressive symptoms. The sample consisted of 203 nurses employed at a 350‐bed metropolitan hospital. The research questionnaire included: (a) the Maferr Inventory of Feminine Values, (b) the Bem Sex Role Inventory, (c) the Zung Self‐Rating Depression Scale, and (d) demographic data. It was found that a strong and positive association existed between traditional attitudes toward feminine sex roles and depressive symptoms. However, relationships between feminine traits and depressive symptoms were not found. Data analysis also indicated statistically significant relationships between both androgenous traits, masculine traits, and lack of depressive symptoms. Limitations in scope and sampling procedures were discussed. In addition, the significance to nursing was discussed. 相似文献
90.
Glenn Ritchie Kenneth Still John Rossi III Marni Bekkedal Andrew Bobb Darryl Arfsten 《Journal of toxicology and environmental health. Part B, Critical reviews》2013,16(4):357-451
Over 2 million military and civilian personnel per year (over 1 million in the United States) are occupationally exposed, respectively, to jet propulsion fuel-8 (JP-8), JP-8 +100 or JP-5, or to the civil aviation equivalents Jet A or Jet A-1. Approximately 60 billion gallons of these kerosene-based jet fuels are annually consumed worldwide (26 billion gallons in the United States), including over 5 billion gallons of JP-8 by the militaries of the United States and other NATO countries. JP-8, for example, represents the largest single chemical exposure in the U.S. military (2.53 billion gallons in 2000), while Jet A and A-1 are among the most common sources of nonmilitary occupational chemical exposure. Although more recent figures were not available, approximately 4.06 billion gallons of kerosene per se were consumed in the United States in 1990 (IARC, 1992). These exposures may occur repeatedly to raw fuel, vapor phase, aerosol phase, or fuel combustion exhaust by dermal absorption, pulmonary inhalation, or oral ingestion routes. Additionally, the public may be repeatedly exposed to lower levels of jet fuel vapor/aerosol or to fuel combustion products through atmospheric contamination, or to raw fuel constituents by contact with contaminated groundwater or soil. Kerosene-based hydrocarbon fuels are complex mixtures of up to 260+ aliphatic and aromatic hydrocarbon compounds (C 6 -C 17+ ; possibly 2000+ isomeric forms), including varying concentrations of potential toxicants such as benzene, n-hexane, toluene, xylenes, trimethylpentane, methoxyethanol, naphthalenes (including polycyclic aromatic hydrocarbons [PAHs], and certain other C 9 -C 12 fractions (i.e., n-propylbenzene, trimethylbenzene isomers). While hydrocarbon fuel exposures occur typically at concentrations below current permissible exposure limits (PELs) for the parent fuel or its constituent chemicals, it is unknown whether additive or synergistic interactions among hydrocarbon constituents, up to six performance additives, and other environmental exposure factors may result in unpredicted toxicity. While there is little epidemiological evidence for fuel-induced death, cancer, or other serious organic disease in fuel-exposed workers, large numbers of self-reported health complaints in this cohort appear to justify study of more subtle health consequences. A number of recently published studies reported acute or persisting biological or health effects from acute, subchronic, or chronic exposure of humans or animals to kerosene-based hydrocarbon fuels, toconstituent chemicals of these fuels, or to fuel combustion products. This review provides an in-depth summary of human, animal, and in vitro studies of biological or health effects from exposure to JP-8, JP-8 +100, JP-5, Jet A, Jet A-1, or kerosene. 相似文献