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81.
Extraction and immunochemical characterization of cholecystokinin-like peptides from pig and rat brain 总被引:2,自引:2,他引:2 下载免费PDF全文
S W Ryder J Eng E Straus R S Yalow 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(6):3892-3896
Two major classes of immunoreactive cholecystokinin peptides (iCCK) have been identified in rat and pig brains: (i) large basic peptides (big iCCK) resembling the 33-amino acid porcine cholecystokinin (pCCK33) in size and charge; (ii) small acidic peptides (small iCCK) resembling the COOH-terminal fragments of CCK. Boiling 0.1 M HCl maximally extracts big iCCK; boiling 0.1 M NaOH maximally extracts small iCCK. The differences in hormonal forms removed by these extractants are not likely to be due to enzymatic conversion during the extraction procedures. Fractionation on Sephadex G-50 and starch gel electrophoresis combined with radioimmunoassay using three antisera of different specificities--(i) directed towards the NH2 terminus of pCCK33, (ii) produced by immunization with COOH-terminal fragment CCK8, (iii) produced by immunization with COOH-terminal fragment CCK4--are consistent with the hypothesis that a major fraction of big iCCK may represent intact cholecystokinin with a COOH-terminal extension, as has recently been suggested for gastrin, a molecule having a COOH-terminal pentapeptide identical with that of cholecystokinin. 相似文献
82.
Erythropoietic activity is known to be closely associated with marrow iron uptake. A modification of the standard measure of plasma iron turnover has been developed in which erythron transferrin uptake (ETU) rather than iron uptake has been calculated. The ETU has the advantage of providing a parameter of erythroid marrow activity independent of change produced by plasma iron and transferrin saturation. Measurements in 80 patients with anemia were compared to the normal value of 60 +/- 12 mumol/L whole blood/d. The mean ETU for ten patients with severe aplastic anemia and for six patients with pure red-cell aplasia were 12 +/- 8 and 12 +/- 11 mumol/L whole blood/d, respectively. In ten transfusion-dependent patients with renal failure under dialysis therapy, the mean value was 35 +/- 11, while ten other dialyzed patients who were transfusion independent had a mean ETU of 73 +/- 21 mumol/L whole blood/d. Sixteen patients with hemolytic anemia had an average ETU of 400 +/- 130, while 28 patients with ineffective erythropoiesis had a mean value of 474 +/- 147 mumol/L whole blood/d. While patients with hypoproliferative anemia showed no relation between the severity of anemia and ETU, those with hyperproliferative erythroid marrow showed increasing values as the anemia became more severe. Sequential measurements in patients with aplastic anemia under treatment and in thalassemic patients under transfusion therapy showed the value of this measurement in monitoring the effects of treatment on erythroid marrow activity. It is concluded that the measurement of ETU provides a more direct ferrokinetic evaluation of erythroid activity in anemic states. 相似文献
83.
Emily A Nizialek Jessica L Mester Vineet K Dhiman Dominic J Smiraglia Charis Eng 《European journal of human genetics : EJHG》2015,23(11):1538-1543
Germline KLLN promoter hypermethylation was recently identified as a potential genetic etiology of the cancer predisposition syndrome, Cowden syndrome (CS), when no causal PTEN gene mutation was found. We screened for KLLN promoter methylation in a large prospective series of CS patients and determined the risk of benign and malignant CS features in patients with increased methylation both with and without a PTEN mutation/variant of unknown significance. In all, 1012 CS patients meeting relaxed International Cowden Consortium criteria including 261 PTEN mutation-positive CS patients, 187 PTEN variant-positive CS patients and 564 PTEN mutation-negative CS patients, as well as 111 population controls were assessed for germline KLLN promoter methylation by MassARRAY EpiTYPER analysis. KLLN promoter methylation was analyzed both as a continuous and a dichotomous variable in the calculation of phenotypic risks by stepwise logistic regression and Kaplan–Meier/standardized incidence ratio methods, respectively. Significantly increased KLLN promoter methylation was seen in CS individuals with and without a PTEN mutation/VUS compared with controls (P<0.001). Patients with high KLLN promoter methylation have increased risks of all CS-associated malignancies compared with the general population. Interestingly, KLLN-associated risk of thyroid cancer appears to be gender and PTEN status dependent. KLLN promoter methylation associated with different benign phenotypes dependent on PTEN status. Furthermore, increasing KLLN promoter methylation is associated with a greater phenotype burden in mutation-negative CS patients. Germline promoter hypermethylation of KLLN is associated with particular malignant and benign CS features, which is dependent on the PTEN mutation status. 相似文献
84.
Mayra Guerrero Amit Pursnani Akhil Narang Michael Salinger Dee Dee Wang Mackram Eleid Susheel K. Kodali Isaac George Lowell Satler Ron Waksman Christopher U. Meduri Vivek Rajagopal Ignacio Inglessis Igor Palacios Mark Reisman Marvin H. Eng Hyde M. Russell Ashish Pershad Charanjit Rihal 《JACC: Cardiovascular Interventions》2021,14(8):859-872
ObjectivesThe aim of this study was to assess 1-year clinical outcomes among high-risk patients with failed surgical mitral bioprostheses who underwent transseptal mitral valve-in-valve (MViV) with the SAPIEN 3 aortic transcatheter heart valve (THV) in the MITRAL (Mitral Implantation of Transcatheter Valves) trial.BackgroundThe MITRAL trial is the first prospective study evaluating transseptal MViV with the SAPIEN 3 aortic THV in high-risk patients with failed surgical mitral bioprostheses.MethodsHigh-risk patients with symptomatic moderate to severe or severe mitral regurgitation (MR) or severe mitral stenosis due to failed surgical mitral bioprostheses were prospectively enrolled. The primary safety endpoint was technical success. The primary THV performance endpoint was absence of MR grade ≥2+ or mean mitral valve gradient ≥10 mm Hg (30 days and 1 year). Secondary endpoints included procedural success and all-cause mortality (30 days and 1 year).ResultsThirty patients were enrolled between July 2016 and October 2017 (median age 77.5 years [interquartile range (IQR): 70.3 to 82.8 years], 63.3% women, median Society of Thoracic Surgeons score 9.4% [IQR: 5.8% to 12.0%], 80% in New York Heart Association functional class III or IV). The technical success rate was 100%. The primary performance endpoint in survivors was achieved in 96.6% (28 of 29) at 30 days and 82.8% (24 of 29) at 1 year. Thirty-day all-cause mortality was 3.3% and was unchanged at 1 year. The only death was due to airway obstruction after swallowing several pills simultaneously 29 days post-MViV. At 1-year follow-up, 89.3% of patients were in New York Heart Association functional class I or II, the median mean mitral valve gradient was 6.6 mm Hg (interquartile range: 5.5 to 8.9 mm Hg), and all patients had MR grade ≤1+.ConclusionsTransseptal MViV in high-risk patients was associated with 100% technical success, low procedural complication rates, and very low mortality at 1 year. The vast majority of patients experienced significant symptom alleviation, and THV performance remained stable at 1 year. 相似文献
85.
Weng SW Liou CW Lin TK Wei YH Lee CF Eng HL Chen SD Liu RT Chen JF Chen IY Chen MH Wang PW 《The Journal of clinical endocrinology and metabolism》2005,90(9):5037-5040
OBJECTIVE: A common variant in mitochondrial DNA (mtDNA) at bp 16189 (T-->C transition) has been associated with small birth size, adulthood hyperglycemia, and insulin resistance in Caucasians. In this study, we investigated whether mtDNA 16189 variant is associated with metabolic syndrome in Chinese subjects. METHODS: Six hundred fifteen Chinese adults, aged 40 yr or older, were recruited in this study. The 16189 variant of mtDNA was detected using PCR and restriction enzyme digestion. Metabolic syndrome was diagnosed on modified National Cholesterol Education Program Adult Treatment Panel III guidelines, using body mass index (BMI) instead of waist circumference. An association study was performed with chi2 test and logistic regression analysis. RESULTS: The prevalence of the 16189 variant was higher in patients with metabolic syndrome than in those without: 44% (125 of 284) vs. 33.2% (110 of 331) (P = 0.006). The association between this 16189 variant of mtDNA and metabolic syndrome (P = 0.021) remained significant even after correcting for age and BMI. As to the individual traits, the prevalence of fasting plasma glucose of at least 110 mg/dl (> or =6.1 mmol/liter) [(51.5% (121 of 235) vs. 42.1% (160 of 380); P = 0.023], type 2 diabetes mellitus [48.1% (113 of 235) vs. 39.2% (149 of 380); P = 0.031], and hypertriglyceridemia [44.3% (104 of 235) vs. 35.8% (136 of 380); P = 0.037] were significantly higher in subjects harboring the 16189 variant of mtDNA than those with the wild type. However, the prevalence of hypertension [53.2% (125 of 235) vs. 47.6% (181 of 380); P = 0.180], BMI greater than 25 kg/m2 [48.5% (114 of 235) vs. 43.9% (167 of 380); P = 0.270], and low high-density lipoprotein cholesterol [61.3% (144 of 235) vs. 54.7% (208 of 380); P = 0.111] did not reach a significant difference between the two groups. Furthermore, there was a trend of increasing frequency of occurrence of the 16189 variant in individuals having an increasing number of components of metabolic syndrome (Ptrend < 0.005). CONCLUSION: Our data strongly suggest that mtDNA 16189 variant underlies susceptibility to metabolic syndrome in the Chinese population. 相似文献
86.
Salman Haq M.D. Masi Khaja M.D. Jeffery J. Holt B.S. John Kassotis M.D. Eng. Sci. D. F.A.C.C. 《The International journal of angiology》2006,15(1):16-19
The QT dispersion (QTd) is a non-invasive means of identifying those patients at an increased risk of developing sudden cardiac death (SCD). Although
levofloxacin has a minimal effect on the QTc interval, isolated reports of QT prolongation, polymorphic ventricular tachycardia with a normal QT interval and TdP have
been reported. The purpose of this study was to examine the effect of intravenous levofloxacin on the QT interval and QTd. Of the 50 patients who were deemed candidates to receive intravenous levofloxacin, 29 met the eligibility criteria and were
enrolled in this study. A 12-lead ECG was performed before the initiation of levofloxacin (baseline), and on days 3 and 5.
The QTc
min, QTc
max and the QTd were calculated. Measurements where made by two independent observers blinded to the patients’ clinical status. The QTd increased significantly on days 3 and 5 following the initiation of therapy [QTd (baseline) 33.3 ± 20 ms, QTd (day 3) 64.4 ± 31.3 ms (p = 0.023), QTd (day 5) 66.8 ± 20.3 ms, (p = 0.008)]. The increase in the QTd was significantly longer in men than women. Although women had a shorter baseline QTd compared to men, this did not achieve statistical significance. Intravenous levofloxacin was found to significantly increase
the QTd, which was more pronounced in men compared to women. Its effect on the QTd may increase the risk of developing a potentially fatal ventricular arrhythmia. Therefore, care must be taken when prescribing
this medication to patients with a pre-existing risk of developing SCD. 相似文献
87.
Sarah Prinsloo Diane Novy Larry Driver Randall Lyle Lois Ramondetta Cathy Eng Gabriel Lopez Yisheng Li Lorenzo Cohen 《Journal of pain and symptom management》2018,55(5):1276-1285
Context
Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of cancer treatment and may adversely affect quality of life (QOL) for years.Objectives
We explored the long-term effects of electroencephalographic neurofeedback (NFB) as a treatment for CIPN and other aspects of QOL.Methods
Seventy-one cancer survivors (mean age 62.5; 87% females) with CIPN were randomized to NFB or to a waitlist control (WLC) group. The NFB group underwent 20 sessions of NFB where rewards were given for voluntary changes in electroencephalography. Measurements of pain, cancer-related symptoms, QOL, sleep, and fatigue were obtained at baseline, end of treatment, and one and four months later.Results
Seventy one participants enrolled in the study. At the end of treatment, 30 in the NFB group and 32 in the WLC group completed assessments; at four months, 23 in the NFB group and 28 in the WLC completed assessments. Linear mixed model analysis revealed significant group × time interaction for pain severity. A general linear model determined that the NFB group had greater improvements in worst pain (primary outcome) and other symptoms such as numbness, cancer-related symptom severity, symptom interference, physical functioning, general health, and fatigue compared with the WLC group at the end of treatment and four months (all P < 0.05). Effect sizes were moderate or large for most measures.Conclusion
NFB appears to result in long-term reduction in multiple CIPN symptoms and improved postchemotherapy QOL and fatigue. 相似文献88.
89.
Drug-Induced Esophagitis 总被引:7,自引:0,他引:7
Jibah Eng M.B. M.A. F.R.C.S. F.I.C.A. Sabanathan Sabanathan M.B. D.M. F.R.C.S. F.I.C.A. 《The American journal of gastroenterology》1991,86(9):1127-1133
Drug-induced esophagitis is being recognized increasingly in the past few years. We have reviewed 175 cases with a view to classifying this disease based on pathology. Drug-induced esophageal injury tends to occur at the anatomical site of narrowing, with the middle third behind the left atrium predominating. The disease is classified broadly into two groups. The first group is transient and self-limiting, as exemplified by tetracycline- and emepronium-induced injury (57.3%). The second is the persistent esophagitis group, often with stricture with two distinct entities: 1) patients on nonsteroidal antiinflammatory agents whose injury is aggravated by gastroesophageal reflux (26.2%) (reflux aggravated), and 2) patients with potassium chloride and quinidine sulfate-induced injury (16.2%) (persisting drug injury). We report a case that highlights the pathophysiology (delayed transit, persisting potassium within the stricture) of this type of injury which is not reflux aggravated. 相似文献
90.
Seroprevalence of Chlamydia pneumoniae infection in Taiwan 总被引:4,自引:0,他引:4
OBJECTIVES: To survey the seroprevalence of Chlamydia pneumoniae (C. pneumoniae) infection in healthy subjects in Taiwan. MATERIALS AND METHODS: We used microimmunofluorescence antibody assay to survey the prevalence of antibodies to C. pneumoniae in 620 serum samples from healthy subjects aged 6 months to 86 years in Taiwan. RESULTS: The mean prevalence (+/-SD) of IgG antibodies against C. pneumoniae at titer greater than or equal 1:16 was 55.8% (range 7.8-81.8%). The antibody prevalence was low in children under the age of 10 years (7.8%), and increased rapidly with age. Most individual acquired infection during the second and third decades of life with highest antibody prevalence reached up to 81.8% at fifth decade of life and remained high (70%) thereafter. CONCLUSIONS: Chlamydia pneumoniae infection is highly endemic in Taiwan. These data contribute to the understanding of asymptomatic infections with C. pneumoniae in general population and should serve as a basis for studies on the role of C. pneumoniae infections and their related diseases. 相似文献