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51.
The central amygdala (CeA) has a unique role in integrating stress and the rewarding effects of ethanol (EtOH) and plays a major role in the development of EtOH dependence via signaling of corticotropin‐releasing factor (CRF). A recent report by Herman and colleagues (2013) entitled “Novel Subunit‐Specific Tonic GABA Currents and Differential Effects of Ethanol in the Central Amygdala of CRF Receptor‐1 Reporter Mice” is the first study to investigate inhibitory tonic currents in relation to CRF signaling in the CeA. The findings of that study significantly enhance our understanding of inhibitory tonic currents in the CeA and give insight into how EtOH may differentially affect CRF signaling within the CeA, leading to the development of EtOH dependence. This commentary will focus on the recent findings of Herman and colleagues and will discuss the effects of EtOH on the entire anxiety/emotion circuitry. 相似文献
52.
Nishit Patel M.D. Talla A. Rousan M.D. Marvin D. Peyton M.D. Chittur A. Sivaram M.D. F.A.C.C. F.A.S.E. 《Echocardiography (Mount Kisco, N.Y.)》2014,31(6):E181-E184
Sinus of Valsalva aneurysm (SVA) is a rare cardiac anomaly that can be congenital or acquired. We report 2 cases of SVA. The first case involves a 59‐year‐old male presenting with frequent syncope. Echocardiogram revealed a large right SVA obstructing the right ventricular outflow tract (RVOT). The second case involves a 21‐year‐old female presenting with sudden onset chest pain and a continuous machinery murmur. Echocardiogram revealed a ruptured right SVA into the right atrium. Although advanced percutaneous techniques have been implemented in the correction of this anomaly, open‐heart surgery with or without aortic valve replacement remains the treatment of choice. 相似文献
53.
Marvin W Kronenberg Gerald I Cohen Marlo F Leonen Thomas A Mladsi Marcelo F Di Carli 《Journal of nuclear cardiology》2006,13(4):544-553
BACKGROUND: Nonischemic dilated cardiomyopathy (NIDCM) is associated with left ventricular remodeling, hypertrophy, and mitochondrial metabolic abnormalities in vitro. We evaluated the hypothesis that energy supply, as judged by the rate of myocardial oxidative metabolism, is inadequate to meet oxygen demand in patients with NIDCM compared with normal subjects. METHODS AND RESULTS: We used positron emission tomography to determine the myocardial carbon 11 acetate decay rate (kmono) as an index of energy supply, and we compared kmono with the rate-pressure product (RPP) as an index of metabolic demand in 7 patients with NIDCM and 7 normal subjects. The mean kmono value (SEM) was 0.060 +/- 0.006 min(-1) in NIDCM patients versus 0.054 +/- 0.002 in normal subjects (P = not significant). The RPP was 9949 +/- 931 beats/min.mm Hg in NIDCM patients and 6521 +/- 476 in normal subjects (P = .007). The relationship of kmono to this index of demand (kmono/RPP) was 6.2 x 10(-6) in NIDCM patients but was 8.5 x 10(-6) in normal subjects (P = .003). Thus RPP, as an index of myocardial oxygen demand, was poorly matched by the rate of oxidative metabolism in those patients with NIDCM. The kmono was closely related to RPP in normal subjects (r = 0.83, P = .02) but not in NIDCM patients. Furthermore, there was no significant relationship between kmono and wall stress as another index of oxygen demand. CONCLUSIONS: These results are consistent with a mitochondrial metabolic abnormality in heart failure. This metabolic mismatch detected by positron emission tomography may contribute to the pathophysiology of congestive heart failure and left ventricular remodeling. 相似文献
54.
Jin L Chico-Galdo V Massart C Gervy C De Maertelaere V Friedman M Van Sande J 《The Journal of endocrinology》2008,198(2):301-307
Chronic administration of acrylamide has been shown to induce thyroid tumors in rat. In vitro acrylamide also causes DNA damage, as demonstrated by the comet assay, in various types of cells including human thyroid cells and lymphocytes, as well as rat thyroid cell lines. In this work, mice were administered acrylamide in their drinking water in doses comparable with those used in rats, i.e., around 3-4 mg/kg per day for mice treated 2, 6, and 8 months. Some of the mice were also treated with thyroxine (T(4)) to depress the activity of the thyroid. Others were treated with methimazole that inhibits thyroid hormone synthesis and consequently secretion and thus induces TSH secretion and thyroid activation. These moderate treatments were shown to have their known effect on the thyroid (e.g. thyroid hormone and thyrotropin serum levels, thyroid gland morphology...). Besides, T(4) induced an important polydipsia and degenerative hypertrophy of adrenal medulla. Acrylamide exerted various discrete effects and at high doses caused peripheral neuropathy, as demonstrated by hind-leg paralysis. However, it did not induce thyroid tumorigenesis. These results show that the thyroid tumorigenic effects of acrylamide are not observed in another rodent species, the mouse, and suggest the necessity of an epidemiological study in human to conclude on a public health policy. 相似文献
55.
Marvin A. Konstam John Idoine Joshua Wynne William Grossman Lawrence Cohn J.Robert Beck Joseph Kozlowski B.Leonard Holman 《The American journal of cardiology》1983,51(7):1144-1148
Using equilibrium (gated) radionuclide ventriculography, right ventricular (RV) function was studied in 22 adults with pulmonary hypertension and in 16 patients without evidence of cardiac disease. To assess the effect of volume overload on RV performance in pulmonary hypertension, RV ejection fractions were compared in patients with and without left-to-right shunts due to atrial septal defect (ASD). In addition, the effect of ASD repair on RV function was examined. In 14 patients with pulmonary hypertension without RV volume overload (group I), the RV ejection fraction (0.35 ± 0.11, mean ± standard deviation [SD]) was significantly lower than in the normal group (0.47 ± 0.11, p < 0.01). In 8 patients with left-to-right shunts due to ASD (group II) and with RV systolic pressures similar to those in group I, the mean RV ejection fraction (0.53 ± 0.15) was normal and was significantly higher than in group I (p < 0.01). Right ventricular end-diastolic volumes, estimated from combined radionuclide and hemodynamic data, were higher (p < 0.01) in group II patients (171 ± 70 ml/m2) than in group I patients (70 ± 13 ml/m2). In 5 patients who underwent isolated shunt repair, mean RV ejection fraction decreased postoperatively from 0.57 ± 0.17 to 0.40 ± 0.12 (p < 0.05). It is concluded that (1) pulmonary hypertension frequently causes a decrease in RV systolic function due to abnormal afterload; (2) in patients with RV volume overload due to left-to-right shunt, systolic function, as measured by the ejection fraction, remains normal despite pulmonary hypertension, possibly through the Starling mechanism; and (3) RV systolic function often decreases after repair of an ASD. 相似文献
56.
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
57.
Relationship between pain and opioid analgesics on the development of delirium following hip fracture 总被引:12,自引:0,他引:12
Morrison RS Magaziner J Gilbert M Koval KJ McLaughlin MA Orosz G Strauss E Siu AL 《The journals of gerontology. Series A, Biological sciences and medical sciences》2003,58(1):76-81
BACKGROUND: Delirium and pain are common following hip fracture. Untreated pain has been shown to increase the risk of delirium in older adults undergoing elective surgery. This study was performed to examine the relationship among pain, analgesics, and other factors on delirium in hip fracture patients. METHODS: We conducted a prospective cohort study at four New York hospitals that enrolled 541 patients with hip fracture and without delirium. Delirium was identified prospectively by patient interview supplemented by medical record review. Multiple logistic regression was used to identify risk factors. RESULTS: Eighty-seven of 541 patients (16%) became delirious. Among all subjects, risk factors for delirium were cognitive impairment (relative risk, or RR, 3.6; 95% confidence interval, or CI, 1.8-7.2), abnormal blood pressure (RR 2.3, 95% CI 1.2-4.7), and heart failure (RR 2.9, 95% CI 1.6-5.3). Patients who received less than 10 mg of parenteral morphine sulfate equivalents per day were more likely to develop delirium than patients who received more analgesia (RR 5.4, 95% CI 2.4-12.3). Patients who received meperidine were at increased risk of developing delirium as compared with patients who received other opioid analgesics (RR 2.4, 95% CI 1.3-4.5). In cognitively intact patients, severe pain significantly increased the risk of delirium (RR 9.0, 95% CI 1.8-45.2). CONCLUSIONS: Using admission data, clinicians can identify patients at high risk for delirium following hip fracture. Avoiding opioids or using very low doses of opioids increased the risk of delirium. Cognitively intact patients with undertreated pain were nine times more likely to develop delirium than patients whose pain was adequately treated. Undertreated pain and inadequate analgesia appear to be risk factors for delirium in frail older adults. 相似文献
58.
Heather Olson Tiffany Rudloe Tobias Loddenkemper Marvin B. Harper Amir A. Kimia 《The American journal of emergency medicine》2018,36(8):1386-1390
Background and aims
Children with first complex febrile seizure (CFS) are often admitted for observation. The goals of this study were 1) to assess the risk of seizure recurrence during admission, 2) to determine whether early EEG affects acute management.Design/methods
We retrospectively reviewed a cohort of children 6–60 months of age admitted from a Pediatric Emergency Department for first CFS over a 15 year period. We excluded children admitted for supportive care of their febrile illness. Data extraction included age, gender, seizure features, laboratory and imaging studies, EEG, further seizures during admission, and antiepileptic drugs (AEDs) given.Results
One hundred eighty three children met inclusion criteria. Seven patients had seizures during the admission (7/183 or 3.8%) Since 38 children were loaded with anti-epileptic medication during their visit, the adjusted rate is 7/145 or 4.8.Increased risk of seizure recurrence during admission was observed in children presenting with multiple seizures (P = 0.005).EEG was performed in 104/183 children (57%) and led to change in management in one patient (1%, 95% C.I. 0.05–6%). Six of the 7 children with seizure had an EEG. The study was normal in 3 and findings in the other 2 did not suggest/predict further seizures during the admission.Conclusions
Children with first CFSs are at low risk for seizure recurrence during admission. Multiple seizures at presentation are associated with risk of early recurrence and may warrant an admission. EEG had limited effect on acute management and should not be an indication for admission. 相似文献59.
Dr. Eugene P. Hughes Jr. M.D. Dr. Malcolm C. Veidenheimer M.D. Dr. Marvin L. Corman M.D. John A. Coller M.D. 《Diseases of the colon and rectum》1982,25(3):215-218
Electrocoagulation is an effective treatment modality for localized cancer of the distal rectum. Proper selection remains
the key to successful treatment. Of potentially curable patients with cancer of the rectum followed up for a median of five
years, 69 per cent had no evidence of cancer at the end of the study period. Gross tumor morphology defined two distinct groups
with regard to outcome after electrocoagulation. Ninety-two per cent of patients with polypoid/exophytic tumors as compared
to 33 per cent of patients with ulcerative lesions had successful treatment. Based on these results, the authors believe that
lesions that are exophytic represent early cancers with a low incidence of nodal spread and, as such, can be treated by electrocoagulation
with confidence. As a palliative measure, the authors found electrocoagulation to yield equivocal results.
Read at the meeting of the American Society of Colon and Rectal Surgeons, Colorado Springs, Colorado, June 7 to 11, 1981. 相似文献
60.
Effects of medroxyprogesterone and estradiol on the recovery of spermatogenesis in irradiated rats 总被引:1,自引:0,他引:1
Shetty G Weng CC Bolden-Tiller OU Huhtaniemi I Handelsman DJ Meistrich ML 《Endocrinology》2004,145(10):4461-4469
Suppression of intratesticular testosterone (ITT) levels is required for spermatogenic recovery in rats after irradiation, but maintenance of peripheral testosterone (T) levels is important for many male functions. Considering the preservation of peripheral T while suppressing ITT, we tested the effects of a combination of a progestin, medroxyprogesterone acetate (MPA), plus T on spermatogenic recovery after irradiation, and compared its effects to those of T alone or T combined with estradiol (E2). Rats were given testicular irradiation (6 Gy) and treated during wk 3-7 after irradiation with MPA + T, or the individual steroids with or without GnRH antagonist (GnRH-ant), or GnRH-ant alone, or T + E2. Whereas GnRH-ant alone stimulated differentiation in 55% of tubules 13 wk after irradiation compared with 0% in irradiated-only rats, the addition of MPA reduced the percentage of tubules showing differentiation to 18%. However, T or MPA alone or the combination of the two induced germ cell differentiation in only 2-4% of tubules. In contrast, E2 stimulated differentiation in 88% of tubules, and T combined with E2 still resulted in differentiation in 30% of tubules. Although both MPA and E2 suppressed ITT levels to approximately 2% of control (2 ng/g testis), MPA was a less effective stimulator of spermatogenic recovery than E2 or GnRH-ant alone. MPA's function as a weak androgen was likely responsible for inhibiting spermatogenic recovery, as was the case for all other tested androgens. Thus, for clinical protection or restoration of spermatogenesis after radiation or chemotherapy by suppressing T production, MPA, at least in the doses used in the present study, is suboptimal. The combination of an estrogen with T appears to be most effective for stimulating such recovery. 相似文献