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21.
Comparison of the subacute toxicity and efficacy of 3-hydroxypyridin-4- one iron chelators in overloaded and nonoverloaded mice 总被引:3,自引:1,他引:3
Five orally effective iron chelators of the 3-hydroxypyridin-4-one series have been administered intraperitoneally to iron-overloaded and nonoverloaded male mice at a dose of 200 mg/kg/24 h for a total of 60 days to investigate the effect on iron loading and toxicity. There was a significant reduction in hepatic iron at the end of the study in the iron-overloaded mice with all compounds studied using chemical iron quantitation (P less than .001) and with Perls' stain (P less than .01). Liver iron removal with the hydroxypyridinones ranged from 37% with CP20 to 63% with CP51, compared with 46% removal for desferrioxamine (DFO). There was no significant reduction in splenic or cardiac iron with any chelator. There were no deaths in iron-overloaded animals receiving any of the hydroxypyridin-4-ones, but significantly more deaths in the nonoverloaded groups as a whole (P less than .03). No weight loss was observed with any chelator. Significant reductions in hemoglobin and white cell count were observed with CP20(L1). No histologic abnormalities of kidney, spleen, bone marrow, or stifle joints were observed. Intracytoplasmic inclusion bodies were observed in the centrilobular hepatocytes of animals administered each of the hydroxypyridin-4-ones, while the DFO-treated and control groups showed no such changes. 相似文献
22.
Detection of anti-HTLV-I Tax antibodies in HTLV-I enzyme-linked immunosorbent assay-negative individuals 总被引:10,自引:0,他引:10
Ehrlich GD; Glaser JB; Abbott MA; Slamon DJ; Keith D; Sliwkowski M; Brandis J; Keitelman E; Teramoto Y; Papsidero L 《Blood》1989,74(3):1066-1072
The HTLV-I tax gene protein (Tax) is not packaged within the mature viral particle from which the proteins for the commercially available enzyme-linked immunosorbent assay (ELISA) are derived. Screening of 162 individuals within a cohort of white intravenous (IV) drug abusers, previously identified as having an increased incidence of HTLV-I infection, demonstrated that seven of them had antibodies to the HTLV-I Tax protein but tested negative in HTLV-I ELISAs and Western blots prepared from purified virion proteins. Three out of 35 individuals in other behaviorally defined high-risk groups also displayed this limited pattern of reactivity to HTLV-I proteins. The presence of the anti-HTLV- I p40/Tax antibodies was determined by radioimmunoprecipitation assay (RIPA), which also revealed low levels of anti-env reactivity. The specificity of the anti-p40 reactivity was confirmed on specific Tax ELISAs and Western blots prepared from recombinantly produced Tax. In vitro gene amplification by the polymerase chain reaction (PCR) was used to establish the presence of sequences homologous to HTLV-I proviral DNA in four/four of these HTLV-I ELISA negative, Tax ELISA/Tax western blot/RIPA positive individuals. These data suggest that the true incidence of HTLV-I infection within high-risk cohorts is greater than previously reported. 相似文献
23.
EG Burden RW Walker DJ Ferguson AMF Goubran JR Howell JB John F Khan JS McGrath JP Evans 《Annals of the Royal College of Surgeons of England》2021,103(3):173
IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery. 相似文献
24.
Stacey A. Santi Michael S. C. Conlon Margaret L. Meigs Stacey M. Davidson Kyle Mispel-Beyer Deborah P. Saunders 《Current oncology (Toronto, Ont.)》2022,29(3):1544
Smoking during cancer treatment is associated with reduced treatment response and cancer recurrence in patients with tobacco-related cancers. The purpose of this study was to examine smoking characteristics in head and neck cancer patients (n = 503) with a history of smoking and examine the impact of an intensive clinical tobacco intervention to patients who were currently smoking. All participants completed an interviewer-administered questionnaire at study enrollment which examined smoking behaviours, motivations to quit, and strategies used to cessate smoking. Follow-up assessments were completed at 6- and 12-months which monitored whether patients had quit smoking, remained cessated, or continued to smoke since study recruitment. For those who were currently smoking (n = 186, 37.0%), an intensive clinical tobacco intervention that utilized the 3A’s—Ask, Advise, Arrange—and the Opt-Out approach was offered to assist with smoking cessation at their new patient visit and followed-up weekly during their head and neck radiation therapy for 7 weeks. At 6 months, 23.7% (n = 41) of those who were smoking successfully quit; 51.2% quit ‘cold turkey’ (defined as using no smoking cessation assistance, aids or pharmacotherapy to quit), while 34.9% used pharmacotherapy (varenicline (Champix)) to quit. On average, it took those who were smoking 1–5 attempts to quit, but once they quit they remained cessated for the duration of the study. Although the head and neck cancer patients in this study reported high levels of nicotine dependence, many were able to successfully cessate. 相似文献
25.
Osama Al‐Jabrah BDS MSc JBPD Raghda Al‐Shammout BDS JBOrth Waddah El‐Naji BDS JBRestDent Mahasen Al‐Ajarmeh BDS JBPD Abdel‐Hakeem Al‐Quran BDS JB 《Journal of prosthodontics》2010,19(4):286-293
Purpose: The aims of this study were to compare gender differences in the width and length of the maxillary right central incisor and the horizontal and vertical overlap of the anterior teeth and to determine the relationships of these two intraoral dental biometric measurements with the amount of gingival display during smiling. Materials and Methods: A total of 61 men and 66 women were included in this study. For each participant, the gingival tissue display during smiling was judged to be either visible or not, and the maximum mesiodistal and incisogingival dimensions of the maxillary right central incisor were measured, along with the amount of horizontal and vertical overlap of anterior teeth using a digital caliper. Gender differences in these parameters and the relationship between subjects showing gingival display when smiling and the two intraoral dental biometric measurements were determined. Statistical analyses of data were performed using SPSS (V11) software. The mean scores for gender were calculated, and a Student's t‐test was used to identify significant differences between both groups. Significance level was set to 0.05. Results: The age of the participants ranged between 23 and 52, with a mean of 33.47 ± 9.07 years. A relatively small percentage of the subjects (22.05%) displayed gingiva when smiling. More women displayed gingiva when smiling than men, with a 2:1 female:male ratio. Men exhibited significantly (p < 0.05) wider (8.76 ± 0.66 mm) and longer (10.28 ± 0.88 mm) central incisors compared to women (7.92 ± 0.72 mm; 9.27 ± 0.93 mm width and length, respectively). No gender differences were found in the width‐to‐length ratio. Subjects with gingival display had significantly more horizontal (4.28 ± 1.21 mm; p < 0.001), and vertical (3.52 ± 0.66 mm; p < 0.05) overlap of anterior teeth compared to those who did not display gingiva when smiling (2.40 ± 1.03 and 2.30 ± 0.93 mm, respectively). Conclusions: Significantly more women displayed gingiva in smiling. Men had significantly wider and longer central incisors. No differences were recorded between men and women relative to both the horizontal and vertical anterior tooth overlap. Subjects who displayed gingiva when smiling had more horizontal and vertical overlap of anterior teeth. 相似文献
26.
Discoid lupus erythematosus is a manifestation of chronic cutaneous lupus erythematosus with a small risk of systemic involvement. In this review article, the role of predisposing factors such as haplotype, hormones, antibodies and sunlight are discussed. The clinical features, including variants and associations, and management options are presented. 相似文献
27.
Nicholas Risko Emilie JB Calvello Sarah Stewart de Ramirez Mayur Narayan Jon Mark Hirshon 《International journal of emergency medicine》2011,4(1):1-2
The clinical findings of Takatsubo Cardiomyopathy and acute myocardial infarction can be very similar. While Takatsubo cardiomyopathy rarely leads to severe complications, acute myocardial infarction can be life threatening. Treatment of both these conditions is different and so it is imperative for clinicians to have a high index of suspicion for either. Several EKG differences between the two entities have been proposed. This article summarizes the EKG changes most likely seen in Takatsubo cardiomyopathy and compares them to those seen in Acute Myocardial infarction. 相似文献
28.
Danielle R. Bouchard Bianca Porneala Ian Janssen Marie-France Langlois Jean-Patrice Baillargeon Caroline S. Fox James B. Meigs Ralph B. D'Agostino Michael Pencina Marie-France Hivert 《Journal of diabetes and its complications》2013,27(3):214-218
AimMid-life obesity is associated with T2D risk. However, less is known about the cumulative effect of obesity during adulthood.MethodsFramingham Offspring Study participants who had an examination at 35 ± 2 years and were initially free of T2D were included in this study (N = 1026). A cumulative excess weight (CEW) score (year*kg/m2) was calculated until T2D diagnostic or the end of follow-up.ResultsEighty-four individuals (8.2%) developed T2D over 20 ± 6 years. Mean CEW scores were 118.0 ± 114.6 year*kg/m2 in individuals who developed T2D and 30.2 ± 91.4 year*kg/m2 in those who did not develop T2D (P < 0.01). T2D risk was doubled for each standard deviation increase in the CEW score (OR = 1.99 [1.64-2.40]; P < 0.001). However, CEW score was only significantly associated with T2D incidence for participants with a baseline BMI < 25 kg/m2 (OR = 2.13 [1.36–3.36]; P < 0.001).ConclusionsAccumulating weight between the mid-thirties to the mid-fifties increases the risk of developing T2D. However, BMI in mid-thirties remains a stronger predictor of T2D risk. 相似文献
29.
30.
Macon WR; Williams ME; Greer JP; Hammer RD; Glick AD; Collins RD; Cousar JB 《Blood》1996,87(4):1474-1483
Natural killer (NK)-like T cells are major histocompatibility complex- unrestricted cytotoxic T cells that are surface CD3-positive, express NK-cell antigens, and rearrange their T-cell receptor. Most neoplasms arising from this T-cell subpopulation have been a chronic lymphoproliferative disease referred to as T-large granular lymphocyte (LGL) leukemia. Only 10 NK-like T-cell lymphomas have been described in detail previously; this study presents the clinicopathologic features of six others and distinguishes these lymphomas from T-LGL leukemia. All patients presented with B-symptoms and often had marked hepatosplenomegaly without significant peripheral lymphadenopathy. Four of the six patients were immunosuppressed. All had CD3, CD8, CD56- positive tumors, presumably of hepatosplenic (n = 3), intestinal (n = 1), pulmonary (n = 1), or nodal (n = 1) origin. Three patients had lymphomatous bone marrow infiltrates, and four had peripheral blood involvement by neoplastic large lymphocytes, some of which had a blastic appearance or resembled virocytes. Azurophilic granules, ultrastructurally corresponding to cytoplasmic dense core and/or double density granules, were seen in all cases. T-cell clonality was shown in five tumors by Southern blot analysis, and three had abnormal karyotypes. Two untreated patients died 20 days after presentation, and three patients who received combination chemotherapy died within 5 months of presentation. One patient remains in complete remission 22 months after treatment. These findings suggest NK-like T-cell lymphomas are aggressive, are clinicopathologically distinct from T-LGL leukemia, and should be in the differential diagnosis of extranodal T-cell lymphoproliferations, including those in immunosuppressed patients. Furthermore, the LGL morphology, phenotype, and tissue distribution of some NK-like T-cell lymphomas suggest they arise from thymic- independent T cells of the hepatic sinusoids and intestinal mucosa. 相似文献