tbuckley/cabot-search huggingface dataset:
Oxygen utilization and ventilation during exercise in patients with chronic cardiac failure.
Authors: K TWeber, G TKinasewitz, J SJanicki, A PFishman
Journal: Circulation (1982)

Muscular work requires the integration of cardiopulmonary mechanisms for gas exchange and O2 delivery. In patients with chronic cardiac failure, the response of these mechanisms may be impaired, and the pattern of O2 utilization (VO2) and gas exchange during exercise would thus provide an objective assessment of the severity of heart failure. Accordingly, rates of air flow, O2 uptake, CO2 elimination and minute ventilation were determined during progressive treadmill exercise in 62 patients with stable heart failure. Exercise cardiac output, systemic O2 extraction and lactate production were measured directly in 40 patients with heart failure of varying severity. As the severity of heart failure increased from class A to D, there was a progressive decrease in exercise capacity (from 1157 +/- 154 to 373 +/- 157 seconds) and maximum VO2 (23 +/- 3.2 to 8.4 +/- 1.5 ml/min/kg). These decreases corresponded with the reduced maximum cardiac output and stroke volume during exercise. The appearance of anaerobic me...
Sarcomere length-tension relations in living rat papillary muscle.
Authors: F JJulian, M RSollins
Journal: Circulation Research (1975)

Small papillary muscles about 2 mm long and 0.2 mm thick were dissected from the right ventricles of 16-19 day-old rats. Resting (between twitches) and active (at twitch peaks) striation patterns were photographed in living muscles using a light microscope. External muscle length was varied from Lmax, the length at which peak twitch tension was maximum, to 0.75Lmax, the length at which peak twitch tension was about 10% of maximum. Resting and active tension versus muscle length curves were similar to those obtained from other papillary muscle preparations. Resting average sarcomere length at Lmax was about 2.23 mu; it decreased with decreasing muscle length in the range between Lmax and 0.75Lmax. Near 0.75Lmax, resting average sarcomere length was about 1.5-1.6mu. Considerable internal shortening occurred during contractions, and the active average sarcomere lengths measured at the twitch peaks were less than the resting values. At Lmax, the active average sarcomere length was 1.98mu. At 0.75Lmax, there w...
Large artery function in patients with chronic heart failure. Studies of brachial artery diameter and hemodynamics.
Authors: J MArnold, G EMarchiori, J RImrie, G LBurton, P WPflugfelder, W JKostuk
Journal: Circulation (1991)

BACKGROUNDAlthough progressive chronic congestive heart failure (CHF) is associated with elevated systemic vascular resistance and increased impedance to ventricular outflow, the contribution of changes in large artery function has not been well documented in humans.METHODS AND RESULTSWe studied 45 patients with a broad range of clinical severity of CHF and compared noninvasive measurements of brachial artery diameter, flow, and pulse wave velocity with 22 normal controls of similar age. In CHF, mean arterial pressure was lower than in controls (85 +/- 1 versus 93 +/- 2 mm Hg, p less than 0.001), as were brachial artery diameter (4.07 +/- 0.10 versus 4.53 +/- 0.09 mm, p less than 0.001), flow (40.9 +/- 4.1 versus 70.9 +/- 11.5 ml.min-1, p less than 0.02), compliance (1.29 +/- 0.12 versus 2.00 +/- 0.18 cm4.dyne-1.10(-7), p less than 0.002), and conductance (0.49 +/- 0.05 versus 0.76 +/- 0.13 units, p = 0.06). Limb vascular resistance (40.2 +/- 5.0 versus 20.5 +/- 3.1 units, p less than 0.001) and pulse wav...
Tales of How Great Drugs Were Brought Down by a Flawed Rationale—Response
Authors: Edina Komlodi-Pasztor, Dan L. Sackett, Tito Fojo
Journal: Clinical Cancer Research (2013)

We argue that drugs that specifically target mitosis will be more effective if mitosis is common and less so if mitosis is rare. Hence, the occurrence of myelosuppression, following therapy with microtubule-targeting agents and with mitosis-specific agents, reflects the high mitotic activity in the
Angle dependence of ultrasonic backscatter in arterial tissues: a study in vitro.
Authors: EPicano, LLandini, ADistante, MSalvadori, FLattanzi, MMasini, AL'Abbate
Journal: Circulation (1985)

The object of this study was to obtain quantitative data on the angle dependence of reflected ultrasound signals in freshly excised normal human arterial walls and those with different degrees of atherosclerotic involvement (fatty, fibrofatty, fibrous, or calcified). Fifteen specimens were evaluated in each pathologic subset. The backscatter coefficient (BS, expressed as cm-1 X steradians -1), measured at the single frequency of 10 MHz, was evaluated at a normal angle of incidence of the interrogating beam to the tissue sample and over an angular span of 60 degrees (+/- 30 degrees around normal incidence, 2 degree steps). BS measured at normal incidence separated normal (10(-2) X 0.155 +/- 0.018; mean +/- SE) from fibrofatty (10(-1) X 0.0103 +/- 0.008), fibrous (10(-1) X 0.182 +/- 0.016), and calcified (0.202 +/- 0.016) specimens; normal and fatty (10(-3) X 0.759 +/- 0.142) and fibrofatty and fibrous samples could not be distinguished from each other in a statistically significant way. Angular scattering ...
Effects of a calcium-entry blocker (diltiazem) on regional myocardial flow and function during exercise in conscious dogs.
Authors: MMatsuzaki, K PGallagher, JPatritti, TTajimi, W SKemper, F CWhite, JRoss
Journal: Circulation (1984)

We examined the effects of diltiazem, a calcium-entry blocker, on exercise-induced myocardial ischemia in nine conscious dogs with chronic coronary stenoses. An ameroid constrictor, Doppler flow probe, and hydraulic occluder were placed around the left circumflex coronary artery, and left ventricular pressure was measured (Konigsberg micromanometer). Pairs of ultrasonic crystals were implanted for measuring left ventricular systolic wall thickening (% delta WTh) in control (left ventricular anterior wall) and ischemic (left ventricular posterior wall) regions, and regional myocardial blood flow was measured with the microsphere method. Eighteen days (average) after surgery mean coronary blood flow velocity had decreased and reactive hyperemic flow velocity after 10 sec of coronary occlusion was markedly reduced, but % delta WTh at rest remained normal, indicating collateral development. Control treadmill exercise was performed for 3.7 min (average), and 2 hr later administration of 0.3 mg/kg diltiazem was...
Cardiac cycle length modulates cardiovascular regulation that is dependent on previous beat contraction history.
Authors: B KSlinker
Journal: Circulation Research (1991)

Previous studies of the beat-to-beat regulation of left ventricular performance in the intact cardiovascular system have shown that the performance of the left ventricle on any one beat is influenced by the mechanical events of the previous beat, so-called previous beat contraction history. The general hypothesis investigated in this study is that previous beat contraction history occurs because of the perturbation of one or more biochemical processes with time courses that are long relative to one cardiac cycle. If this is true, then previous beat contraction history should depend on the interval between beats and, therefore, should extend beyond the previous beat to two, or even three, previous beats as heart rate is increased. Hemodynamic responses to random preload and afterload changes were measured in 11 anesthetized open-chest dogs on right heart bypass at three paced heart rates. Multiple linear regression was used to analyze these hemodynamic sequences and identify variables from the previous one...
Low-fat diet and regular, supervised physical exercise in patients with symptomatic coronary artery disease: reduction of stress-induced myocardial ischemia.
Authors: GSchuler, GSchlierf, AWirth, H PMautner, HScheurlen, MThumm, HRoth, FSchwarz, MKohlmeier, H CMehmel
Journal: Circulation (1988)

The effects of physical exercise and normalization of serum lipoproteins on stress-induced myocardial ischemia were studied in 18 patients with coronary artery disease, stable angina pectoris, and mild hypercholesterolemia (total serum cholesterol 242 +/- 32 mg/dl). These patients underwent a combined regimen of low-fat/low-cholesterol diet and regular, supervised physical exercise at high intensity for 12 months. At 1 year serum lipoproteins has been lowered to ideal levels (serum cholesterol 202 +/- 31 mg/dl, low-density lipoproteins 130 +/- 30 mg/dl, very low-density lipoproteins 22 +/- 15 mg/dl, serum triglycerides 105 [69 to 304] mg/dl) and physical work capacity was improved by 21% (p less than .01). No significant effect was noted on high-density lipoproteins, probably as a result of the low-fat/high-carbohydrate diet. Stress-induced myocardial ischemia, as assessed by thallium-201 scintigraphy, was decreased by 54% (p less than .05) despite higher myocardial oxygen consumption. Eighteen patients m...
Intelligent nanogels with self-adaptive responsiveness for improved tumor drug delivery and augmented chemotherapy
Authors: Xin Li, Helin Li, Changchang Zhang, Andrij Pich, Lingxi Xing, Xiangyang Shi
Journal: Bioactive Materials (2021)

For cancer nanomedicine, the main goal is to deliver therapeutic agents effectively to solid tumors. Here, we report the unique design of self-adaptive ultrafast charge-reversible chitosan-polypyrrole nanogels (CH-PPy NGs) for enhanced tumor delivery and augmented chemotherapy. CH was first grafted with PPy to form CH-PPy polymers that were used to form CH-PPy NGs through glutaraldehyde cross-linking via a miniemulsion method. The CH-PPy NGs could be finely treated with an alkaline solution to generate ultrafast charge-reversible CH-PPy-OH-4 NGs (R-NGs) with a negative charge at a physiological pH and a positive charge at a slightly acidic pH. The R-NGs display good cytocompatibility, excellent protein resistance, and high doxorubicin (DOX) loading efficiency. Encouragingly, the prepared R-NGs/DOX have prolonged blood circulation time, enhanced tumor accumulation, penetration and tumor cell uptake due to their self-adaptive charge switching to be positively charged, and responsive drug delivery for augmented chemotherapy of ovarian carcinoma in vivo. Notably, the tumor accumulation of R-NGs/DOX (around 4.7%) is much higher than the average tumor accumulation of other nanocarriers (less than 1%) reported elsewhere. The developed self-adaptive PPy-grafted CH NGs represent one of the advanced designs of nanomedicine that could be used for augmented antitumor therapy with low side effects.
Criteria for two-staged arterial switch operation for simple transposition of great arteries.
Authors: MNakazawa, KOyama, YImai, KNojima, HAotsuka, GSatomi, HKurosawa, ATakao
Journal: Circulation (1988)

We analyzed hemodynamic variables in patients with transposition of the great arteries with intact ventricular septum (simple transposition) after pulmonary artery banding and Blalock-Taussig anastomosis to establish the criteria for two-staged arterial switch operation. The study included 35 patients who underwent the switch operation after banding and anastomosis; two died shortly after surgery, and one died of tachycardia 31 days after the operation. The left-to-right ventricular pressure ratio was above 0.83 in all surviving patients, 0.68 and 0.63 in the two operative deaths, and 0.84 in the other death. In the 32 surviving patients, angiographically determined left ventricular (LV) end-diastolic volume and ejection fraction averaged 147 +/- 46(SD)% of normal and 0.64 +/- 0.12, respectively. We also measured LV mass using angiographic LV semiaxes and end-diastolic LV posterior wall thickness obtained from an echocardiogram. These variables of the patients who died were not different from those of the...
Influence of a prostaglandin endoperoxide analogue on the canine pulmonary vascular bed.
Authors: P JKadowitz, A LHyman
Journal: Circulation Research (1977)

We evaluated the effects of an analogue of the prostaglandin endoperoxide, PGH2, in the canine pulmonary vascular bed. The analogue increased pulmonary arterial pressure whereas cardiac output and left atrial pressure were unchanged. Although pulmonary vascular resistance was increased markedly, only small increases in systemic vascular resistance were observed. In experiments in which blood flow to a lobe was maintained constant, the analogue produced dose-related increases in lobar arterial and small vein pressure but little change in left atrial pressure. These data suggest that the analogue increased resistance to flow by constricting intrapulmonary veins and upstream vessels presumed to be small arteries. The increase in resistance was similar when the lung was perfused with dextran or with blood. In addition, the analogue increased inflation pressure; however, similar increments in vascular resistance were obtained in ventilated and nonventilated lung lobes. Indomethacin, in doses which abolished re...
Underwater Piecemeal Endoscopic Mucosal Resection (EMR) With Hot Snare of a Giant Sigmoid Polyp
Authors: L Gonzalez-Gonzalez, J Colan-Hernandez, I Marín, V Moreno, N Caballero, M Puig, I Iborra, J Troya, H Uchima
Journal: Endoscopy (2021)

We present an 84-year-old male where a CT scan was performed for constipation study. The CT-scan showed a giant lobulated sigmoid lesion and an appendicular adenocarcinoma.In the colonoscopy we saw a giant sigmoid polyp that obstructed the intestinal lumen and was located between two angulations, but there were no endoscopic signs of deep invasion. We performed a piecemeal underwater EMR with hot snare to avoid a subtotal colectomy. The anatomopathological study showed a tubulo-villous adenoma with high and low-grade dysplasia with foci of intramucosal adenocarcinoma (pTis).Given the patient’s comorbidities it was decided to do only endoscopic follow-up
Three types of naturally occurring modified lipoproteins induce intracellular lipid accumulation due to lipoprotein aggregation.
Authors: V VTertov, A NOrekhov, I ASobenin, Z AGabbasov, E GPopov, A AYaroslavov, V NSmirnov
Journal: Circulation Research (1992)

Low density lipoprotein (LDL) from patients with coronary atherosclerosis and diabetes mellitus as well as in vitro desialylated LDL, glycosylated LDL, and lipoprotein (a) caused a twofold to fourfold rise in cholesteryl ester in cultured human blood monocytes and intimal smooth muscle cells isolated from normal aorta. Native LDL from healthy subjects failed to induce intracellular lipid accumulation. We have demonstrated by laser correlative photometry and gel filtration chromatography that in vivo and in vitro modified lipoproteins form aggregates under cell culture conditions. The degree of modified lipoprotein aggregation directly correlated with the ability of these lipoproteins to elevate the cholesteryl ester content of cultured cells. Modified lipoprotein aggregates isolated by gel filtration induced a threefold to fivefold elevation in cellular cholesteryl ester content. Aggregates of 125I-modified LDL were taken up and degraded fivefold to sevenfold more effectively as compared with nonaggregate...
Aseptic Meningitis and Intravenous Immunoglobulin Therapy
Authors: Yadollah Harati
Journal: Annals of Internal Medicine (1995)

Letters15 February 1995Aseptic Meningitis and Intravenous Immunoglobulin TherapyYadollah Harati and Aziz Taher ShaibaniYadollah HaratiSearch for more papers by this author and Aziz Taher ShaibaniSearch for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-122-4-199502150-00019 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail TO THE EDITOR:Sekul and colleagues [1] described the association between aseptic meningitis and high-dose intravenous immunoglobulin and reported that 11% (6 of 54) of their patients developed aseptic meningitis after receiving intravenous immunoglobulin. However, they did not mention the specific immunoglobulin product or products they used, although they asserted that a change in the “commercial lot or product, for unknown reasons, was effective in preventing the recurrence of aseptic meningitis”.Considering the high incidence of aseptic meningitis reported by these authors and the fact that different intravenous immunoglobulin products vary in the type and amount of the vehicle and ...REFERENCE1. Sekul EA, Cupler EJ, Dalakas MC. Aseptic meningitis associated with high-dose intravenous immunoglobulin therapy: frequency and risk factors. Ann Intern Med. 1994; 121:259-62. Google Scholar Author, Article, and Disclosure InformationAffiliations: PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics Cited byAcute Aseptic Meningitis Associated with Administration of Immunoglobulin in Children: A Case Report and Review of the Literature 15 February 1995Volume 122, Issue 4Page: 316-317KeywordsIntravenous immunoglobulinMeningitis ePublished: 15 August 2000 Issue Published: 15 February 1995 Copyright & PermissionsCopyright © 1995 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...
Prospective Evaluation of the Feasibility of Structured Distance EUS Training By A Virtual EUS Course with live Cases
Authors: V Dhir, R Shah, P Udawat
Journal: Endoscopy (2021)

Methods 21 trainees were chosen from a group of applicants with certified expertise in endoscopy with regular access to linear echoendoscope. The training was imparted over virtual platform over 16 classes of 90 minute duration each, held over 3 months. The curriculum included endoscope handling, cleaning, disinfection and keyboard controls. This was followed by 12 classes on linear EUS anatomy of mediastinum, pancreatico-biliary region, rectum and EUS-guided FNA. Trainees were exposed to interventional EUS procedures done by international experts. Virtual screen included the endoscopists hand movements, and EUS image. Questions over technical issues were encouraged during the class. The assessment included a questionnaire and video assessment after each class and at the end. Study end points included a video assessment of satisfactory identification of 1. Sub-carinal space 2. Head of Pancreas 3. Common bile duct 4.body and tail of pancreas.
Late reperfusion for acute myocardial infarction limits the dilatation of left ventricle without the reduction of infarct size.
Authors: AHirayama, TAdachi, SAsada, MMishima, SNanto, HKusuoka, KYamamoto, YMatsumura, MHori, MInoue
Journal: Circulation (1993)

BACKGROUNDWhile previous clinical studies have shown a possible beneficial effect of the reperfusion performed at a relatively late phase of acute myocardial infarction (late reperfusion) in preventing left ventricular enlargement, the mechanism has not been clarified.METHODS AND RESULTSOf 89 patients with an initial anterior myocardial infarction, reperfusion was successful in 69. These 69 were divided into three groups according to the time required to achieve reperfusion after the onset of symptoms: early-reperfused (  6 hours from the onset to reperfusion; n = 19). The 20 patients whose infarct-related artery were occluded in the acute phase as well as 1 month later was classified as nonreperfused. Infarct size, evaluated as defect volume by 201Tl single-photon emission computed tomography 1 month after the onset, was 1593 +/- 652 units (mean +/- SD) in...
Differentiation of transiently ischemic from infarcted myocardium by serial imaging after a single dose of thallium-201.
Authors: G MPohost, L MZir, R HMoore, K AMcKusick, T EGuiney, G ABeller
Journal: Circulation (1977)

Myocardial 201Tl uptake and regional blood flow by the microsphere technique were determined in anesthetized dogs undergoing either 20 min of coronary occlusion and 100 min of reperfusion (N = 10) or 120 min of occlusion (N = 4). In both groups, 201Tl was injected intravenously after 10 min of occlusion. In transiently occluded dogs, regional flow at the time of 201Tl administration was reduced to 8 +/- 3% of normal flow in endocardial layers of the central ischemic zone. After 100 min of reperfusion, flow values were not significantly different from normal. 201Tl activity after reperfusion rose to 56 +/- 5% of normal, demonstrating that redistribution of the radionuclide occurred during the reflow period. In animals with persistent occlusion, there was a significant relationship between 201Tl uptake and flow (r = 0.95) and no evidence of redistribution of 201Tl during the two hour occlusion period. In another five dogs receiving 201Tl, serial gamma camera images obtained during reperfusion showed increas...
Abnormalities in heart membranes and myofibrils during bacterial infective cardiomyopathy in the rabbit.
Authors: C WTomlinson, S LLee, N SDhalla
Journal: Circulation Research (1976)

We studied hearts from sham-operated and uninfected catheterized rabbits as well as from rabbits at early and late stages of cardiomyopathy and failure after 3 and 6 days of infection with Streptococcus viridans. No ultrastructural abnormalities or biochemical changes in membrane and myofibrillar activities were seen in 3-day uninfected hearts. In 6-day uninfected hearts there were decreased sarcolemmal M2+ ATPase, Na+-K+ ATPase, adenylate cyclase and calcium binding, microsomal calcium binding and uptake, and myofibrillar Ca2+-stimulated ATPase as well as increased mitochondrial calcium uptake. Slight ultrastructural changes also were apparent in 6-day uninfected hearts. At both early and late stages of infective cardiomyopathy and failure there were varying degrees of depression in sarcolemmal Mg2+ ATPase, Na+-K+ ATPase, adenylate cyclase and calcium binding, microsomal calcium binding, calcium uptake and basal ATPase, and myofibrillar Ca2+-stimulated ATPase activities. However, sarcolemmal Ca2+ ATPase ...
Whistleblowing and Misconduct at Large Pharmaceutical Firms
Authors: Takanao Hashimoto, Akihiko Ozaki, Tetsuya Tanimoto
Journal: JAMA (2021)

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