tbuckley/cabot-search huggingface dataset:
Depression of contractility following stretches and releases applied during contraction to single frog atrial cardiac cells.
Authors: M Tarr, J W Trank, K K Goertz
Journal: Circulation Research (1984)

The effects of stretches and releases on the contractile performance of isolated single frog atrial cells (Rana catesbeiana) were investigated. A stretch or release was imposed on the cell--either during a contraction (test) or before the onset of contraction (control)--and the contractile performance (length, velocity and force) of the test contraction was compared with that of the control contraction to determine whether the stretch or release imposed on the contracting cell altered the contractility of the cell. We found that the velocity of cell (and sarcomere) shortening for the remainder of the test contraction following either a stretch or release was markedly less than that occurring at the same time in the control contraction. This decreased velocity occurred even though the force in the test contraction was less than that in the control contraction and the sarcomere length was longer in the test contraction than in the control contraction. These results indicate that after a stretch or release imposed on the contracting cell, the force-velocity relationship at any given length and time is depressed than had the stretch or release not been imposed on the contracting cell. Thus, stretches and releases applied to the contracting single cardiac cell either produce a long-term depression in the contractility of the cell, or that the contractility at any given time and sarcomere length depends markedly on the history of the contraction.
Graduate Medical Education, 2006-2007
Authors: Sarah E. Brotherton, Sylvia I. Etzel
Journal: JAMA (2007)

Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy | Continue JAMA HomeNew OnlineCurrent IssueFor Authors Publications JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry (1919-1959) Podcasts Clinical Reviews Editors' Summary Medical News Author Interviews More JN Learning / CMESubscribeJobsInstitutions / LibrariansReprints & Permissions Terms of Use | Privacy Policy | Accessibility Statement 2023 American Medical Association. All Rights Reserved Search All JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Forum Archive JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry Input Search Term Sign In Individual Sign In Sign inCreate an Account Access through your institution Sign In Purchase Options: Buy this article Rent this article Subscribe to the JAMA journal
The Quantitative Determination of Coronary Flow with a Positron Emitter (Rubidium-84)
Authors: ALBERTO COHEN, JAMES P. GALLAGHER, EIDE-DITTMAR LUEBS, ZOLTAN VARGA, JIRO YAMANAKA, EDWARD J. ZALESKI, GERHARD BLUEMCHEN, RICHARD J. BING
Journal: Circulation (1965)

An objective method for the quantitative measurement of the coronary blood flow in ml./min. using a coincidence counting system with rubidium-84, a positron emitter, is described. Accidental coincidence counts arising from independent annihilation of positrons were greatly reduced by simple shielding. The coronary blood flow was calculated by the extrapolation of the clearance values to zero time. At this time the myocardial extraction ratio of rubidium-84 is unity and clearance is equal to flow. The accuracy of this method was demonstrated on the isolated perfused dog heart. It was found that the rate of change of the extraction ratio of rubidium-84 in the isolated perfused dog heart and in man was not altered with changes in flow. The finding that nitroglycerin increases the coronary blood flow in patients without coronary artery disease while decreasing it in patients with coronary artery disease was confirmed.
PD08-03: Inhibition of MEK/ERK- and JNK-Dependent Expression of Interleukin-6 and Interleukin-8 Targets Basal-Like Breast Cancer Stem Cells.
Authors: JM Balko, RS Cook, MG Kuba, TW Miller, NE Bhola, ME Sanders, IM Meszoely, M Dowsett, H Gomez, CL Arteaga
Journal: Cancer Research (2011)

Abstract Background: Neoadjuvant chemotherapy (NAC) induces a pathological complete response in approximately 30% of triple-negative or basal-like breast cancers (BLBC). However, patients with residual disease often recur after surgery, presumably due to persistent drug-resistant subpopulations with cancer stem cell (CSC)-like properties. Thus, elimination of this CSC compartment in BLBC has the potential to improve survival by reducing post-surgical metastatic recurrences. Methods: We sampled 49 post-NAC breast cancer samples including 22 BLBCs and quantified RNA for 355 cancer-related transcripts using Nanostring technology. Transcripts associated with a high Ki67 in the residual disease (a biomarker of early recurrence) were identified and bioinformatically examined for an association with drug resistance and a CSC phenotype. Loss of DUSP4, a negative feedback regulator of ERK1/2 and JNK1/2, was highly associated with a high post-NAC Ki67. We examined the role of loss of DUSP4 in promoting a drug-resistant, CSC phenotype. Results: Low DUSP4 expression in post-NAC tumors was associated with high ERK1/2 activation and BLBC gene expression. siRNA knockdown of DUSP4 enhanced resistance to anti-cancer chemotherapy (docetaxel, camptothecin). Alternatively, forced DUSP4 expression in breast cancer cell lines abrogated the activation of transcription factors downstream of ERK and JNK and sensitized cells to docetaxel-induced apoptosis. In highly metastastic BLBC cell lines, MEK inhibition with AZD6244 and JNK inhibition with SP600125 significantly reduced mammosphere formation and self-renewal. Inhibition of JNK and MEK reduced IL6 and IL8 expression, two cytokines known to expand the CSC compartment. Reconstitution of exogenous IL6 and IL8 after MEK inhibition restored mammosphere formation potential. Chromatin immunoprecipitation demonstrated that the oncogenic transcription factor ETS-1, an ERK1/2 substrate, binds the IL8 promoter in a MEK1/2-dependent manner. We are currently confirming the association of DUSP4 loss with Ki67, ERK activation, and IL6/IL8 expression in a cohort of 113 post-NAC triple negative breast cancers. Conclusions: Our data demonstrate that loss of DUSP4 in BLBC promotes ERK and JNK activation by impairing negative feedback of these pathways. Activation of ERK and JNK drives expression of IL6 and IL8 expression, possibly through ETS-1 activation. Thus, targeting these signaling pathways may eliminate residual cancer stem cells after neoadjuvant chemotherapy and improve cure rates in BLBC. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr PD08-03.
Junior doctors' hours
Authors: P R Eldridge
Journal: BMJ (1994)

EDITOR, - I wish to correct some misconceptions that may arise from Jesper Poulsen's editorial on the European Union's draft directive on restrictions on hours of work.1 In neurosurgery, pressure to maintain an 83 hour week comes from both trainees and seniors. This is because continental Europeans are not trained to a standard equivalent to that in Britain.

Britain has an accreditation process that assesses trainees and a system that approves training programmes. Clinical experience is viewed as fundamentally important to …
AB0328 Gender Differences in Risk Factors for Cardiovascular Disease in Outpatients with Rheumatoid Arthritis
Authors: J. Primdahl, C.B. Nissen, K. Hørslev-Petersen
Journal: Annals of the Rheumatic Diseases (2014)

<h3>Background</h3> People with rheumatoid arthritis (RA) have an increased risk for cardiovascular disease (CVD) [1,2]. Although male gender is generally associated with a greater risk for cardiovascular related mortality and death, there is, as yet, little knowledge of the impact of gender on the risk factors for CVD in patients with RA. <h3>Objectives</h3> To explore gender differences in the distribution of risk factors and in the risk factors that exceed national recommended levels in outpatients with RA. <h3>Methods</h3> We used data from the first 836 outpatients in a hospital population with RA screened in 30-minute nursing consultations according to the EULAR recommendations [1,2]. Risk factors, such as history of CVD, hypertension or diabetes mellitus (DM), smoking, fasting glucose, total, LDL, HDL cholesterol and Triglycerides, exercise habits, alcohol use, Body Mass Index (BMI) and waist circumference were explored. Logistic regression analyses were used to test for gender differences. <h3>Results</h3> Fewer female than male patients were diagnosed with CVD (OR 0.662; CI 0.452, 0.965; p=0.032) and there were no gender differences in those diagnosed with DM. In the 644 patients without CVD or DM, male patients were more likely to smoke, drink more alcohol than recommended (p&lt;0.001), and to have higher blood pressure (p=0.026) and lower total cholesterol (p=0.006), but to have a higher total-cholesterol/HDL-cholesterol ratio (p&lt;0.001) than female patients. More male patients than female patients displayed too low HDL-cholesterol levels (p=0.014). When comparing female and male patients, and taking the deviations from the recommended levels for the different risk factors into account, female patients had a small but significantly lower risk for elevated blood pressure (OR 0.987) but a higher risk for an increase in waistline above the recommended limits than the male patients (OR 1.023). In addition, female patients had a lower odds ratio (OR 0.681) for an increase in fasting glucose compared to male patients. <h3>Conclusions</h3> In clinical practice, we need to be aware of gender differences in risk factors for development of CVD in order to target interventions. <h3>References</h3> Peters, M.J., et al., EULAR evidence-based recommendations for cardiovascular risk management in patients with rheumatoid arthritis and other forms of inflammatory arthritis. Ann Rheum Dis, 2010. 69(2): p. 325-31. Primdahl J, Clausen J, Hørslev-Petersen K. Results from implementation of systematic screening for cardiovascular risk according to the EULAR recommendations in outpatients with rheumatoid arthritis. Ann Rheum Dis 2013; 72: 11:1771-6 <h3>Disclosure of Interest</h3> None declared <h3>DOI</h3> 10.1136/annrheumdis-2014-eular.2828
A piece of my mind. Coming home
Authors: A. O. Goldstein
Journal: JAMA (1991)

Coming home after vacation is sometimes slightly sad. It's not that your trip was boring or too short. Rather, it's more like a bittersweet dream, when, having suddenly awakened, you are less upset to be awake than sorry you cannot return to your dream. "Please take notice that..." The first day back is always the worst. Restarting routines—unpacking, sorting mail, answering phone messages, washing clothes—these serve a purpose: to center yourself today for tomorrow's work, forgotten while vacationing. The first night back, a few phone calls to family and friends finish the grounding process. Tomorrow, to work, to the hospital. "... the undersigned will bring the above petition on the hearing before this court..." The morning after holds such promise. Invigorated, a refreshed mind can attack daily challenges. Creativity runs high. Many tasks can be solved in a few short hours. The office desk is cleared, and the rooms are ready
Abstract 361: PET imaging of antitumor responses with anti-4-1BB (anti-CD137)
Authors: Helena Escuin-Ordinas, Mohammad Atefi, Charles Ng, Leslie Sharp, Antoni Ribas
Journal: Cancer Research (2012)

Abstract Agonistic antibodies to 4-1BB (CD137), a member of the tumor necrosis factor family expressed on activated T cells, are being tested for immunotherapy in patients with advanced cancers. Being able to study the mechanism of 4-1BB action in vivo using non-invasive approaches would help guiding its clinical development. We used positron emitting tomography (PET) with [18F]FDG to study how 4-1BB mAb modulates the immune system in a mouse model for cancer treatment. The administration of 1mg/kg of the 4-1BB mAb to Balb/c mice induced reproducible CT26 tumor regressions and improved survival (n=8 mice per group, p = 0.006 for survival by log rank test). The mean tumor size (mm) was also strikingly different (5.8 ± 0.20 4-1BB mAb group vs 8.3 ± 0.19 control, on day 7 after 4-1BB mAb; p &amp;lt; 0.0009). All mice responded to the treatment and complete tumor shrinkage was achieved in 75% of cases, 14 days after 4-1BB mAb administration. Using microPET imaging there was markedly increased mean signal (% ID/g) of [18F]FDG at the tumor site and draining lymph nodes (18.4 ± 1.6 4-1BB mAb group vs. 10.3 ± 0.418 control group). Due to the shrinkage of the tumor in the treated group, we hypothesized this higher PET signal is the result of higher activity of immune cells in the site. In a metabolic probe in vitro uptake assay, there was a 7-fold increase in uptake of [3H]DDG in lymphocytes extracted from tumor-draining lymph nodes and a 2-fold increase in tumor infiltrating lymphocytes (TILS) of mice treated with 4-1BB mAb compared to untreated mice, supporting the in vivo PET data. In conclusion, increased uptake of [18F]FDG by PET scans visualizes 4-1BB mAB-induced anti-tumor immune responses and can be used as a pharmacodynamic readout to guide the development of this class of antibodies in the clinic. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 361. doi:1538-7445.AM2012-361
Increased concentrations of polychlorinated biphenyls, hexachlorobenzene, and chlordanes in mothers of men with testicular cancer.
Authors: Lennart Hardell, Bert van Bavel, Gunilla Lindström, Michael Carlberg, Ann Charlotte Dreifaldt, Hans Wijkström, Hans Starkhammar, Mikael Eriksson, Arne Hallquist, Torgny Kolmert
Journal: Environmental Health Perspectives (2002)

An increasing incidence of testicular cancer has been reported from several countries in the Western world during the last decades. According to current hypothesis, testicular cancer is initiated during the fetal period, and exposure to endocrine disruptors, i.e., xenoestrogens, has been of concern. In this investigation we studied the concentrations of the sum of 38 polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyl-dichloroethylene, hexachlorobenzene (HCB), and chlordanes, in 61 cases with testicular cancer and 58 age-matched controls. Furthermore, case and control mothers were also asked to participate, and 44 case mothers and 45 control mothers agreed. They were of similar age. In cases only the concentration on lipid basis of cis-nonachlordane was significantly increased, whereas case mothers showed significantly increased concentrations of the sum of PCBs, HCB, trans- and cis-nonachlordane, and the sum of chlordanes. Among case mothers the sum of PCBs yielded an odds ratio (OR) of 3.8; 95% confidence interval (CI), 1.4-10 was calculated using the median concentration for the control mothers as cutoff value. For HCB, OR = 4.4 (95% CI, 1.7-12); for trans-nonachlordane, OR = 4.1 (95% CI, 1.5-11); for cis-nonachlordane, OR = 3.1 (95% CI, 1.2-7.8); and for sum of chlordanes, OR = 1.9 (95% CI, 0.7-5.0). No consistent different risk pattern was found for seminoma or nonseminoma testicular cancer.
763 DOES HEPATITIS B VIRUS (HBV) CO-INFECTION HAVE ANY IMPACT ON TREATMENT OUTCOME IN CHRONIC HEPATITIS C-PATIENTS ON HEMODIALYSIS?
Authors: R.C. Wahle, C.T. Emori, S.O. Uehara, I.C. Melo, P.F. Pereira, C.M. Rocha, R.M. Perez, I.S. Silva, A.E. Silva, M.L. Ferraz
Journal: Journal of Hepatology (2008)
Heterogeneous response to calcium by individual parathyroid cells.
Authors: F Sun, C K Ritchie, C Hassager, P Maercklein, L A Fitzpatrick
Journal: Journal of Clinical Investigation (1993)

Classical stimulus-secretion theory suggests that each individual cell responds to a given stimulus. We tested this theory by determining the response of single bovine parathyroid cells to calcium with the reverse hemolytic plaque assay (RHPA), an assay that measures hormone release from individual cells. As calcium concentrations decreased, the amount of parathyroid hormone (PTH) released per cell increased, and cells were recruited to release PTH. To confirm that adequate stores of PTH were present, immunocytochemistry and in situ hybridization were performed. To test if cells that did not release PTH were capable of secretion, we performed a sequential RHPA; 47.8% of cells did not release PTH after the first stimulus. After the second exposure to low concentrations of calcium, 26.5% of these "nonsecretory" cells were able to release PTH. We conclude that parathyroid cells are homogeneous for PTH content and synthetic capability. Parathyroid cells respond to changes in extracellular calcium heterogeneously in that more PTH per cell is released, and individual parathyroid cells are "recruited" to release PTH at low calcium concentrations. In addition, parathyroid cells can be induced to secrete suggesting that cells are viable but in a depressed secretory state. Parathyroid cells may exist in an "on" or "off" secretory state.
Long-Term Effects of Levodopa in the Severely Disabled Patient
Authors: Oliver W. Sacks
Journal: JAMA (1970)

<h3>To the Editor.—</h3> For the past 15 months we have been engaged in a long-term study of the effects of levodopa on 60 severely disabled patients with Parkinson's disease, half postencephalitic and half idiopathic, who have been institutionalized for many years in our chronic disease facility. In common with published reports (summarized in an editorial in<i>Brit Med J</i><b>1</b>:446-447, 1970) we have found that the drug was effective, though to a varying degree, in the majority of our patients. However, in contrast to these reports we have observed that the period of benefit has been of limited duration and has been followed<i>in all cases</i>by adverse effects, the latter often progressive, sometimes serious, and occasionally dangerous. We have reported some of our observations in preliminary letters to the<i>Lancet</i><sup>1-4</sup>and are now preparing a comprehensive review of our studies. Meanwhile we wish to comment on the
Distribution of extravascular fluid volumes in isolated perfused lungs measured with H215O.
Authors: T Jones, H A Jones, C G Rhodes, P D Buckingham, J M Hughes
Journal: Journal of Clinical Investigation (1976)

The distributions per unit volume of extravascular water (EVLW), blood volume, and blood flow were measured in isolated perfused vertical dog lungs. A steady-state tracer technique was employed using oxygen-15, carbon-11, and nitrogen-13 isotopes and external scintillation counting of the 511-KeV annihilation radiation common to all three radionuclides. EVLW, and blood volume and flow increased from apex to base in all preparations, but the gradient of increasing flow exceeded that for blood and EVLW volumes. The regional distributions of EVLW and blood volume were almost identical. With increasing edema, lower-zone EVLW increased slightly relative to that in the upper zone. There was no change in the distribution of blood volume or flow until gross edema (100% wt gain) occurred when lower zone values were reduced. In four lungs the distribution of EVLW was compared with wet-to-dry ratios from lung biopsies taken immediately afterwards. Whereas the isotopically measured EVLW increased from apex to base, the wet-to-dry weight ratios remained essentially uniform. We concluded that isotopic methods measure only an "exchangeable" water pool whose volume is dependent on regional blood flow and capillary recruitment. Second, the isolated perfused lung can accommodate up to 60% wt gain without much change in the regional distribution of EVLW, volume, or flow.
THREE CASES OF SUPPURATIVE OTITIS MEDIA; SEVERE SYSTEMIC AND REMOTE DISTURBANCES; RECOVERY AFTER MASTOID OPERATION AND REMOVAL OF POLYPI.
Authors: HIRAM WOODS
Journal: JAMA (1898)

Certain local changes are admitted as indicating need of the mastoid operation. If one or more of the so-called vital indications be present, the demand is emphasized. Apart from these, cases are observed where there is room for legitimate doubt before and after operation; before, because there are no distinctive local signs of pent-up secretion, and yet we see phenomena most easily accounted for by assuming that such a condition exists; after, because no pus is found, and even if the patient recovers, doubt intrudes if operation were really needed to effect cure. The following cases illustrate this fairly well: <h3>Case 1.</h3> —John S., age 30, a white laborer, was admitted to the Maryland University Hospital, February 19, 1896. He had been injured the same day by the falling of an embankment. A fractured pelvis was found. He made an uninterrupted recovery for four weeks, when, the evening temperature, normal
CASE OF SCIRRHUS IN THE DUODENUM: JAUNDICE
Authors: P. H. Williams
Journal: BMJ (1855)

_g ti ttolL d the dose in which the secrt Ef~~~~~c onsist etL8The d i of cutaneous therapeutics cannot, however, Ie aid to be settled.During the prepartion of these Lpers, a communication has appeared in the tontidy Jousra of Medicmne (January 180B), from the pen of no less important a writer than Professor Bennett of Edin- burgh, " On the Treatment of the more Common Forms of 8km Disease met with in Edinburgh," in which the accom- plished author certainly lays down rules about as contrary to those which I have learned to respect, as is possible in the mature of things.The cases on which this practice is
Maternal HL-A Antibodies and Fetal Sex
Authors: K. Johansen, H. Festenstein
Journal: BMJ (1974)

In a study of 960 pregnancies a significantly higher male to female birth ratio was found among primigravidae who developed HL-A antibodies, which was highest where these were monospecific. In the whole group male births predominated in women with antibodies to HL-A 1 and 11 (first locus) and HL-A 5, 12, and 13 and TYT (second locus).