tbuckley/cabot-search huggingface dataset:
Insights From Three-dimensional Echocardiographic Laser Stereolithography
Authors: Dan Gilon, Edward G. Cape, Mark D. Handschumacher, Leng Jiang, Charles Sears, Joan Solheim, Eleanor Morris, John T. Strobel, Stockton M. Miller-Jones, Arthur E. Weyman, Robert A. Levine
Journal: Circulation (1996)

Three-dimensional echocardiography can allow us to address uniquely three-dimensional scientific questions, for example, the hypothesis that the impact of a stenotic valve depends not only on its limiting orifice area but also on its three-dimensional geometry proximal to the orifice. This can affect the coefficient of orifice contraction (Cc = effective/anatomic area), which is important because for a given flow rate and anatomic area, a lower Cc gives a higher velocity and pressure gradient, and Cc, routinely assumed constant in the Gorlin equation, may vary with valve shape (60% for a flat plate, 100% for a tube). To date, it has not been possible to study this with actual valve shapes in patients.Three-dimensional echocardiography reconstructed valve geometries typical of the spectrum in patients with mitral stenosis: mobile doming, intermediate conical, and relatively flat immobile valves. Each geometry was constructed with orifice areas of 0.5, 1.0 and 1.5 cm2 by stereolithography (computerized laser polymerization) (total, nine valves) and studied at physiological flow rates. Cc varied prominently with shape and was larger for the longer, tapered dome (more gradual flow convergence proximal and distal to the limiting orifice): for an anatomic orifice of 1.5 cm2, Cc increased from 0.73 (flat) to 0.87 (dome), and for an area of 0.5 cm2, from 0.62 to 0.75. For each shape, Cc increased with increasing orifice size relative to the proximal funnel (more tubelike). These variations translated into important differences of up to 40% in pressure gradient for the same anatomic area and flow rate (greatest for the flattest valves), with a corresponding variation in calculated Gorlin area (an effective area) relative to anatomic values.The coefficient of contraction and the related net pressure loss are importantly affected by the variations in leaflet geometry seen in patients with mitral stenosis. Three-dimensional echocardiography and stereolithography, with the use of actual information from patients, can address such uniquely three-dimensional questions to provide insight into the relations between cardiac structure, pressure, and flows.
Nitric oxide. A macrophage product responsible for cytostasis and respiratory inhibition in tumor target cells.
Authors: D J Stuehr, C F Nathan
Journal: The Journal of Experimental Medicine (1989)

A metabolic pathway of activated macrophages (M phi) involving oxidation of the guanido nitrogens of L-arginine is required for inhibition of growth and respiration of some target cells. The goal of this study was to identify the M phi metabolite(s) that induce these injuries. The stable products of the L-arginine pathway, NO2- and NO3-, were incapable of causing cytostasis under coculture conditions. However, NO2- became cytostatic upon mild acidification, which favors its transformation into nitrogen oxides of greater reactivity. This suggested that NO. (and/or NO2), recently identified as an M phi metabolite of L-arginine, could be a mediator. Authentic NO. caused cytostasis and respiratory inhibition in L1210 cells in a dose-dependent manner. The mitochondrial lesions caused by NO. were confined to complex 1 and 2, a pattern of injury identical to that seen after coculture with activated M phi. Inclusion of NO. scavenger systems prevented cytostasis from developing in M phi-L1210 cocultures. Thus, M phi-generated NO. can account for L-arginine-dependent cytostasis and respiratory inhibition.
Child sexual abuse.
Authors: F. Eke
Journal: BMJ (1989)

adrenergic casualty department, where further delays would take place and possibly further errors by inexperienced junior staff.Unfortunately, the message of the British Heart Foundation report is deeply ambivalent, doubtless reflecting a "dissensus" in the group.The overall result, however, will be to discourage general practitioners from participating fully and exploiting the major benefits that thrombolvtic treatment can confer.Rather than "contracting out," as the report suggests, I hope that general practitioners will insist on local schemes to bolster their confidence in the full early management of mvocardial infarc- tion.G H HAL.L Exeter EX2 4NT 1 Hall GH.Bolols streptokinase af'ter myocardial inf-arction.Lancct 1987;ii:96-87. 2 British Heart Fouindationi WXorkittg (iroup.Rolc of the general practitioners in managing patients with myotcardial infarction: impact of tltrombolytic trcatmcnt.lBr Mcd 7 1989:299:555-6 (26 Atigttst.Child sexual abuse SIR,-I am pleased that investigations for sexually transmitted diseases including screening tests for gonorrhoea and HIV infection should be done on sexually abused children.'Over two years five children (two girls, three boys) aged 4-71/2 years presented at this teaching hospital, not with a history of sexual abuse but with urethral or vaginal discharge proved to be due to Neisseria gonorrhoea.One 5 year old girl subse- quently admitted to sexual abuse by a 10 year old boy at school.The boy refused to be investigated
Strain rate imaging or doppler myocardial imaging for the detection of regional myocardial ischemia during stress echocardiography: which method is superior?
Authors: Jens-Uwe Voigt, Bert Exner, Kristin Schmiedehausen, Andrej Schmidt, Dierk Werner, Uwe Nixdorff, Frank A. Flachskampf, Werner G. Daniel
Journal: Journal of the American College of Cardiology (2002)
Madness Explained: Psychosis and Human Nature
Authors: N. Lester
Journal: BMJ (2003)

My first close contact with a clinical psychologist was when I was a new consultant, intent on fostering a multidisciplinary approach, during my first ward round. Nervously I pumped up the team spirit in the assembled crowd. In truth, I hadn't a clue what I was going to do. The psychologist looked stern and impenetrable. He took to contradicting everything I said. Desperately I would agree with him, only he would then change his point, saying that I had not understood. We went round like this for a while. I nodded and smiled and adopted what I hoped was not threatening body posture. Eventually I entreated him to spend some time with the patient. Anything to help move things on. I received a barrage of reasons as to why this was …
ANEURYSMS OF THE THORACIC AORTA INVOLVING THE LUNG
Authors: J. Fanning
Journal: BMJ (1922)

THE two cases of aneurvsm of tlle tlioracic aorta described below present several features of considerable clinical and pathological interest.Both aneurysms-ruptured within a fortnight of each other while .under.obser.vation in hospital, and in each case the aneurysmal sac produced extensive changes in the lung.Tlle second case was par- ticularly interesting in its close simulation of clhronic pulmonary tuberculosis.CASE I. W. H., widower, aged 53, a comnmercial traveller, was admitted to Hampstead General Hospital on January 31st, 1922, with a history of four years' gradually increasing dyspnoea on exertion.
Dexamethasone and Postoperative Bleeding After Tonsillectomy in Children—Reply
Authors: Christoph Czarnetzki
Journal: JAMA (2009)

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
Purine Nucleoside Phosphorylase: A New Marker for Free Oxygen Radical Injury to the Endothelial Cell
Authors: Prakash N. Rao, Thomas R. Walsh, Leonard Makowka, Randy S. Rubin, Thomas Weber, James T. Snyder, Thomas E. Starzl
Journal: Hepatology (1990)

The effect of ischemia and reperfusion on purine nucleoside phosphorylase was studied in an isolated perfused rat liver model. This enzyme is localized primarily in the cytoplasm of the endothelial and Kupffer cells; some activity is associated with the parenchymal cells. Levels of this enzyme accurately predicted the extent of ischemia and reperfusion damage to the microvascular endothelial cell of the liver. Livers from Lewis rats were subjected to 30, 45 and 60 min of warm (37° C) no flow ischemia that was followed by a standard reperfusion period lasting 45 min. Purine nucleoside phosphorylase was measured at the end of the no flow ischemia and reperfusion periods as was superoxide generation (O 2 –). Bile production was monitored throughout the no flow ischemia and reperfusion periods. Control perfusions were carried out for 120 min. A significant rise in purine nucleoside phosphorylase levels as compared with controls was observed at the end of ischemia in all the three groups. The highest level, 203.5 ± 29.2 mU/ml, was observed after 60 min of ischemia. After the reperfusion period, levels of purine nucleoside phosphorylase decreased in the 30– and 45–min groups 58.17 ± 9.66 mU/ml and 67.5 ± 17.1 mU/ml, respectively. These levels were equal to control perfusions. In contrast, after 60 min of ischemia, levels of purine nucleoside phosphorylase decreased early in the reperfusion period and then rose to 127.8 ± 14.8 mU/ml by the end of reperfusion (p &lt; 0.0001). Superoxide generation at the beginning of reperfusion was higher than in controls with similar values observed at the end of 30, 45 and 60 min of ischemia. During reperfusion, production of superoxide continued. Bile production was significantly lower at the end of 30 min (0.044 ± 0.026 μl/min/gm), 45 min (0.029 ± 0.0022 μ/min/gm) and 60 min of ischemia (0.022 ± 0.008 μ/min/gm) when compared with bile production by control livers during the corresponding time (0.680 ± 0.195, 0.562 ± 0.133 and 0.480 ± 0.100 μ/min/gm respectively; p &lt; 0.001). During reperfusion, rates of bile production were normal after 30 and 45 min of ischemia. In contrast, significantly lower rates of bile production, 0.046 ± 0.36 μ/min/gm (p &lt; 0.001) occurred during reperfusion after 60 min of ischemia. Control livers during the same period produced 0.330 ± 0.056 μl/min/gm of bile. The results indicate that purine nucleoside phosphorylase levels may be a good index of oxidative injury to the liver in ischemia reperfusion and reliably predict the functional state of the organ after reperfusion.
Platelet-Derived Growth Factor Receptor β–Mediated Phosphorylation of MUC1 Enhances Invasiveness in Pancreatic Adenocarcinoma Cells
Authors: Pankaj K. Singh, Yunfei Wen, Benjamin J. Swanson, Kandavel Shanmugam, Andrius Kazlauskas, Ronald L. Cerny, Sandra J. Gendler, Michael A. Hollingsworth
Journal: Cancer Research (2007)

Abstract MUC1 is a heterodimeric transmembrane glycoprotein that is overexpressed and aberrantly glycosylated in ductal adenocarcinomas. Differential phosphorylation of the MUC1 cytoplasmic tail (MUC1CT) has been associated with signaling events that influence the proliferation and metastasis of cancer cells. We identified a novel tyrosine phosphorylation site (HGRYVPP) in the MUC1CT by mass spectrometric analysis of MUC1 from human pancreatic adenocarcinoma cell lines. Analyses in vitro and in vivo showed that platelet-derived growth factor receptor β (PDGFRβ) catalyzed phosphorylation of this site and of tyrosine in the RDTYHPM site. Stimulation of S2-013.MUC1F cells with PDGF-BB increased nuclear colocalization of MUC1CT and β-catenin. PDGF-BB stimulation had no significant effect on cell proliferation rate; however, it enhanced invasion in vitro through Matrigel and in vivo tumor growth and metastases. Invasive properties of the cells were significantly altered on expression of phosphorylation-abrogating or phosphorylation-mimicking mutations at these sites. We propose that interactions of MUC1 and PDGFRβ induce signal transduction events that influence the metastatic properties of pancreatic adenocarcinoma. [Cancer Res 2007;67(11):5201–10]
DÉBRIDEMENT AN OLD METHOD
Authors: P. I. Nixon
Journal: JAMA (1927)

<h3>To the Editor:</h3> —During the World War there was a great deal published on débridement. W. W. Keen, in his Treatment of War Wounds, for instance, states that "the most important alteration in treatment since the early days of the war is that excision of damaged tissue has become the routine method." It is interesting to find, therefore, that Baron Larrey used this method. It is described in his Memoirs and Campaigns. In describing the campaign of the Rhine in 1789, he wrote: "Desault taught us that, in order to change the nature of wounds from a complicated to a simple state, it was not sufficient to make the part bleed; in order to attain this end, it was necessary to remove the bruised edges with a sharp knife, and then to unite the wound with a suture. In my campaigns in Germany and Egypt, I have profited by the
Adeno-associated Virus 9 Mediated FKRP Gene Therapy Restores Functional Glycosylation of α-dystroglycan and Improves Muscle Functions
Authors: Lei Xu, Pei Juan Lu, Chi-Hsien Wang, Elizabeth Keramaris, Chunping Qiao, Bin Xiao, Derek J Blake, Xiao Xiao, Qi Long Lu
Journal: Molecular Therapy (2013)

Mutations in the FKRP gene are associated with a wide range of muscular dystrophies from mild limb-girdle muscular dystrophy (LGMD) 2I to severe Walker–Warburg syndrome and muscle-eye-brain disease. The characteristic biochemical feature of these diseases is the hypoglycosylation of α-dystroglycan (α-DG). Currently there is no effective treatment available. In this study, we examined the adeno-associated virus serotype 9 vector (AAV9)-mediated gene therapy in the FKRP mutant mouse model with a proline to leucine missense mutation (P448L). Our results showed that intraperitoneal administration of AAV9-FKRP resulted in systemic FKRP expression in all striated muscles examined with the highest levels in cardiac muscle. Consistent with our previous observations, FKRP protein is localized in the Golgi apparatus in myofibers. Expression of FKRP consequently restored functional glycosylation of α-DG in the skeletal and cardiac muscles. Significant improvement in dystrophic pathology, serum creatine kinase levels and muscle function was observed. Only limited FKRP transgene expression was detected in kidney and liver with no detectable toxicity. Our results provided evidence for the utility of AAV-mediated gene replacement therapy for FKRP-related muscular dystrophies. Mutations in the FKRP gene are associated with a wide range of muscular dystrophies from mild limb-girdle muscular dystrophy (LGMD) 2I to severe Walker–Warburg syndrome and muscle-eye-brain disease. The characteristic biochemical feature of these diseases is the hypoglycosylation of α-dystroglycan (α-DG). Currently there is no effective treatment available. In this study, we examined the adeno-associated virus serotype 9 vector (AAV9)-mediated gene therapy in the FKRP mutant mouse model with a proline to leucine missense mutation (P448L). Our results showed that intraperitoneal administration of AAV9-FKRP resulted in systemic FKRP expression in all striated muscles examined with the highest levels in cardiac muscle. Consistent with our previous observations, FKRP protein is localized in the Golgi apparatus in myofibers. Expression of FKRP consequently restored functional glycosylation of α-DG in the skeletal and cardiac muscles. Significant improvement in dystrophic pathology, serum creatine kinase levels and muscle function was observed. Only limited FKRP transgene expression was detected in kidney and liver with no detectable toxicity. Our results provided evidence for the utility of AAV-mediated gene replacement therapy for FKRP-related muscular dystrophies.
Does arousal frequency predict daytime function?
Authors: RN Kingshott, HM Engleman, IJ Deary, NJ Douglas
Journal: European Respiratory Journal (1998)

Patients with the sleep apnoea/hypopnoea syndrome (SAHS) have impaired daytime function with demonstrable sleepiness and impaired cognition. The hypothesis that brief arousals from sleep cause these daytime impairments was tested. One hundred and fifty patients with sleep disordered breathing were studied prospectively, comparing overnight polysomnography with daytime measures of objective sleepiness, psychological well-being and cognitive performance. Significant, but weak (r2<0.1), relationships were seen between several nocturnal measures (apnoea/hypopnoea index, arousals and desaturation variables) and daytime measures of quality of life, well-being, subjective sleepiness, symptoms and cognitive performance. The only significant relationship between nocturnal variables and objective sleepiness was a very weak correlation (r2<0.05) between the lowest oxygen saturation and mean maintenance of wakefulness test (MWT) result. The MWT was better correlated with daytime function than the multiple sleep latency test. This study shows a lack of strong relationships between conventional nocturnal measures and daytime function in patients with sleep disordered breathing.
Effects of Acetazolamide on the Unrinary Excretion of Cyclic AMP and on the Activity of Renal Adenyl Cyclase
Authors: Hector J. Rodriguez, John Walls, Jesse Yates, Saulo Klahr
Journal: Journal of Clinical Investigation (1974)

Acetazolamide, an inhibitor of the enzyme carbonic anhydrase, increased the urinary excretion of cyclic AMP in normal and parathyroidectomized rats. The increase was greater in rats with intact parathyroid glands than in parathyroidectomized rats. This rise in the urinary excretion of cyclic AMP was not due to an increase in urine flow or a change in urine pH. Furosemide caused an increase in urine flow, but did not affect the excretion of cyclic AMP or phosphate. Alkalinization of the urine with bicarbonate did not increase the urinary excretion of phosphate or cyclic AMP. Acetazolamide increased the productionof cyclic AMP by rat renal cortical slices in vitro. This effect was dose-dependent. Acetazolamide also stimulated the activity of renal cortical adenyl cyclase in a dose-dependent manner but had no effect on the activity of cyclic nucleotide phosphodiesterase. The pattern of urinary excretion of cyclic AMP and phosphate after administration of acetazolamide was similar to that observed in rats given parathyroid hormone. It is suggested that acetazolamide stimulates the renal production of cyclic AMP by activating adenyl cyclase and that this may be the mechanism by which this inhibitor of carbonic anhydrase produces phosphaturia.
Enmeshed in Metaphor
Authors: Samuel Vaisrub
Journal: JAMA (1977)

"The United States," writes Lewis H. Lapham in a recent editorial ("A Nation of Dreamers,"<i>Harper's</i>, September 1976, p. 4), "is a nation of dreamers, captivated by the power of metaphor. Whenever possible the American substitutes the symbol for whatever it is that the symbol represents." Contrary to the popular view of himself as a practical, skeptical materialist eager to possess material goods, the American, so maintains Lapham, is a dreamer to whom material acquisitions serve as symbols of some desired immateriality. The latter is manifest in the surrealist atmosphere of the modern novel, in the abstract theories of modern art, in the symbolism of political and business rhetoric, and even in the approaches to sex, where acquisition of the sexual object serves as proof of something else. "The transcendental bias of the American mind," says Lapham, "can turn the whole world into metaphor." Does this "world" include medicine? Does
Why Don't Physicians Follow Clinical Practice Guidelines?
Authors: Michael D. Cabana, Cynthia S. Rand, Neil R. Powe, Albert W. Wu, Modena H. Wilson, Paul-André C. Abboud, Haya R. Rubin
Journal: JAMA (1999)

Despite wide promulgation, clinical practice guidelines have had limited effect on changing physician behavior. Little is known about the process and factors involved in changing physician practices in response to guidelines.To review barriers to physician adherence to clinical practice guidelines.We searched the MEDLINE, Educational Resources Information Center (ERIC), and HealthSTAR databases (January 1966 to January 1998); bibliographies; textbooks on health behavior or public health; and references supplied by experts to find English-language article titles that describe barriers to guideline adherence.Of 5658 articles initially identified, we selected 76 published studies describing at least 1 barrier to adherence to clinical practice guidelines, practice parameters, clinical policies, or national consensus statements. One investigator screened titles to identify candidate articles, then 2 investigators independently reviewed the texts to exclude articles that did not match the criteria. Differences were resolved by consensus with a third investigator.Two investigators organized barriers to adherence into a framework according to their effect on physician knowledge, attitudes, or behavior. This organization was validated by 3 additional investigators.The 76 articles included 120 different surveys investigating 293 potential barriers to physician guideline adherence, including awareness (n = 46), familiarity(n = 31), agreement (n = 33), self-efficacy (n = 19), outcome expectancy (n = 8), ability to overcome the inertia of previous practice (n = 14), and absence of external barriers to perform recommendations (n = 34). The majority of surveys (70 [58%] of 120) examined only 1 type of barrier.Studies on improving physician guideline adherence may not be generalizable, since barriers in one setting may not be present in another. Our review offers a differential diagnosis for why physicians do not follow practice guidelines, as well as a rational approach toward improving guideline adherence and a framework for future research.
New agency set up to identify incompetent doctors
Authors: C. Dyer
Journal: BMJ (2001)

A new agency to catch underperforming or incompetent doctors was unveiled by the UK government this week, in the wake of an official report that confirmed the British GP Harold Shipman, serving life for killing 15 patients, as one of the most prolific serial murderers in history.

But the BMA pointed out that the proposed new National Clinical Assessment Authority would not necessarily detect a doctor like Shipman, and called for a series of measures to improve the monitoring of death rates among GPs' patients and drug prescribing.

The authority, set up to provide “fast track” responses to concerns about doctors, is a reaction not only to the Shipman case but to a series of medical scandals that have rocked public confidence in doctors. These include the cases of the disgraced gynaecologists Rodney Ledward and Richard Neale—struck off the medical register only after years of gross malpractice—and the children's heart surgery saga in Bristol.

The report on Shipman, published last week, suggests that he may have been responsible for the deaths …