tbuckley/cabot-search huggingface dataset:
Virtual cathode effects during stimulation of cardiac muscle. Two-dimensional in vivo experiments.
Authors: J P Wikswo, T A Wisialowski, W A Altemeier, J R Balser, H A Kopelman, D M Roden
Journal: Circulation Research (1991)

We have found that when suprathreshold cathodal stimuli were applied to the epicardium of canine ventricle, impulse propagation originated at a "virtual cathode" with dimensions greater than those of the physical cathode. We report the two-dimensional geometry of the virtual cathode as a function of stimulus strength; the results are compared with the predictions of an anisotropic, bidomain model of cardiac conduction recently developed in our laboratories. Data were collected in six pentobarbital-anesthetized dogs by using a small plaque electrode sewn to the left ventricular epicardium. Arrival times at closely spaced bipolar electrodes oriented radially around a central cathode were obtained as a function of stimulus strength and fiber orientation. The dimensions of the virtual cathode were determined by linear back-extrapolation of arrival times to the time of stimulation. The directional dependence of the conduction velocity was consistent with previous reports: at 1 mA, longitudinal (0 degree) and transverse (90 degrees) velocities were 0.60 +/- 0.03 and 0.29 +/- 0.02 m/sec, respectively. At 7 mA, the longitudinal velocity was 0.75 +/- 0.05 m/sec, whereas there was no significant change in the transverse velocity. In contrast to conduction velocity, the virtual cathode was smallest in the longitudinal orientation and largest between 45 degrees and 60 degrees. Virtual cathode size was dependent on both orientation and stimulus strength: at 0 degree, the virtual cathode was small (approximately 1 mm) and relatively constant over the range of 1-7 mA; at oblique orientations (45 degrees-90 degrees), it displayed a roughly logarithmic dependence on stimulus strength, approximately 1 mm at 1 mA and approximately 3 mm at 7 mA. The bidomain, anisotropic model reproduced both the stimulus strength and the fiber-orientation dependence of the virtual cathode geometry when the intracellular and extracellular anisotropies were 10:1 and 4:1, respectively, but not when the two anisotropies were equal. We suggest that the virtual cathode provides a direct measure of the determinants of cardiac activation; its complex geometry appears to reflect the bidomain, anisotropic nature of cardiac muscle.
Retinitis pigmentosa caused by a homozygous mutation in the Stargardt disease gene ABCR
Authors: Amalia Martínez-Mir, Eva Paloma, Rando Allikmets, Carmen Ayuso, Teresa del Río, Michael Dean, Lluísa Vilageliu, Roser Gonzàlez-Duarte, Susana Balcells
Journal: Nature Genetics (1998)
Placental Localization by Thermography
Authors: R. J. Young
Journal: BMJ (1966)

<h3>OBJECTIVES</h3> To investigate cerebral vasomotor reactivity in five patients with limb shaking transient ischaemic attacks by using transcranial Doppler sonography. <h3>METHOD</h3> Attacks with transient limb shaking were unilateral in four patients and bilateral in one. Internal carotid arteries on the side opposite the abnormal limb movements showed three 90–95% stenoses and three occlusions as assessed by cerebral angiography in three and magnetic resonance angiography and ultrasound in one case each. Reactivity of cerebral resistance vessels was studied by measuring peak mean velocities in the middle cerebral artery (MCA) before and after the application of CO<sub>2</sub> enriched air. Reference values were obtained from 25 normal subjects. <h3>RESULTS</h3> During hypercapnia peak mean velocities slightly decreased in five MCAs (steal phenomenon) and remained unchanged in one MCA opposite the abnormal movements, whereas the other MCAs showed normal reactivities. <h3>CONCLUSION</h3> The delineation of an exhausted cerebral vasoreactivity in all hemispheres opposite the involuntary limb movements suggests that haemodynamic failure is the cause of transient ischaemic attacks with limb shaking.
STUDIES ON THE EPIDEMIOLOGY OF SARCOIDOSIS IN THE UNITED STATES: THE RELATIONSHIP TO SOIL AREAS AND TO URBAN-RURAL RESIDENCE
Authors: John T. Gentry, Harold M. Nitowsky, Max Michael
Journal: Journal of Clinical Investigation (1955)

During World War II, there were 350 recognized cases of sarcoidosis among American Armed Forces personnel.These cases, chosen in a relatively unselected manner, afford an admirable opportunity for investigation into some of the aspects of the epidemiology of this disease.Preliminary studies of this group have demonstrated a striking concentration of patients' birthplaces in the Southeastern United States (1, 2).Although cases in negroes predominated, the observed geographic localization could not be accounted for solely by the distribution of the negro population in the United States.The present investigation, which was concerned with factors which might have in- fluenced this unusual case distribution, revealed an association between the distribution of the cases and certain soil areas.Furthermore, a higher incidence of the disease was found among servicemen from the more rural areas of the Southeast.These correlations may serve as ad- ditional localizing factors for further studies on the epidemiology of sarcoidosis. MATERIAL AND METHODSOf the 350 cases of sarcoidosis diagnosed in World War II servicemen, there were 334 living at the time of this study.Only these were investigated since the compilation of epidemiologic data would be incomplete in those deceased.In many patients the disease was discovered accidentally by routine x-ray examination taken during the course of hospitalization or upon sepa- ration from service.The diagnoses of sarcoidosis were made in American military hospitals scattered over
Long-term Outcome of Transient, Uncomplicated In-Laboratory Coronary Artery Closure
Authors: Alaa E. Abdelmeguid, Patrick L. Whitlow, Shelly K. Sapp, Stephen G. Ellis, Eric J. Topol
Journal: Circulation (1995)

Background Successful reversal of abrupt vessel closure without resultant major ischemic complications (death, Q-wave myocardial infarction, or coronary artery bypass graft surgery) is achieved in nearly half of all cases of abrupt vessel closure. The long-term outcome of these patients has not been previously addressed, and it is not clear whether they have a different prognosis than that of patients who have a successful procedure not associated with transient vessel closure. Methods and Results We examined 4863 consecutive patients who underwent successful percutaneous transluminal coronary angioplasty (PTCA) or directional coronary atherectomy (DCA). Eighty-eight patients had an uncomplicated, successfully reversed transient in-laboratory vessel closure (group 2) and were compared with 4775 patients who had a successful procedure not associated with transient in-laboratory closure (group 1). Clinical follow-up was available in 4839 patients (99.5%), with a mean duration of 41±23 months (range, 1 to 104 months). Survival analysis showed that successfully treated, uncomplicated transient vessel closure per se does not have an adverse effect on long-term prognosis (death, myocardial infarction, or coronary interventions). However, when the procedure (PTCA or DCA) was associated with an increase in creatine kinase–MB (CK-MB), there was a significant adverse effect on long-term outcome. By multivariate logistic regression, an increase in postprocedure CK-MB was the most significant correlate for cardiac death (risk ratio, 1.25; P &lt;.0001). An increase in CK-MB was also the most important correlate for major ischemic complications (death, infarction, or coronary interventions) on follow-up (risk ratio, 1.08; P =.0005). Conclusions Transient, uncomplicated in-laboratory vessel closure per se does not have an adverse long-term effect. However, a concomitant elevation of postprocedure cardiac enzymes has an important and significant adverse effect on long-term outcome. This study suggests that periprocedural creatine kinase isoenzyme determination in patients experiencing in-laboratory coronary closure has important prognostic implications.
Prognostic Value of Lead V <sub>1</sub> ST Elevation During Acute Inferior Myocardial Infarction
Authors: Cheuk-Kit Wong, Wanzhen Gao, Ralph A. Stewart, John K. French, Philip E. Aylward, Jocelyne Benatar, Harvey D. White
Journal: Circulation (2010)

Background— Lead V 1 directly faces the right ventricle and may exhibit ST elevation during an acute inferior myocardial infarction when the right ventricle is also involved. Leads V 1 and V 3 indirectly face the posterolateral left ventricle, and ST depression (“mirror-image” ST elevation) in V 1 through V 3 may reflect concomitant posterolateral infarction. The prognostic significance of V 1 ST elevation during an acute inferior myocardial infarction may therefore be dependent on V 3 ST changes. Methods and Results— In 7967 patients with acute inferior myocardial infarction in the Hirulog and Early Reperfusion or Occlusion-2 (HERO-2) trial, V 1 ST levels were analyzed with adjustment for lead V 3 ST level for predicting 30-day mortality. V 1 ST elevation at baseline, analyzed as a continuous variable, was associated with higher mortality. Unadjusted, each 0.5-mm-step increase in ST level above the isoelectric level was associated with ≈25% increase in 30-day mortality; this was true whether V 3 ST depression was present or not. The odds ratio for mortality was 1.21 (95% confidence interval, 1.07 to 1.37) after adjustment for inferolateral ST elevation and clinical factors and 1.24 (95% confidence interval, 1.09 to 1.40) if also adjusted for V 3 ST level. In contrast, lead V 1 ST depression was not associated with mortality after adjustment for V 3 ST level. V 1 ST elevation ≥1 mm, analyzed dichotomously in all patients, was associated with higher mortality. The odds ratio was 1.28 (95% confidence interval, 1.01 to 1.61) unadjusted, 1.51 (95% confidence interval, 1.19 to 1.92) adjusted for V 3 ST level, and 1.35 (95% confidence interval, 1.04 to 1.76) adjusted for ECG and clinical factors. Persistence of V 1 ST elevation ≥1 mm 60 minutes after fibrinolysis was associated with higher mortality (10.8% versus 5.5%, P =0.001). Conclusion— V 1 ST elevation identifies patients with acute inferior myocardial infarction who are at higher risk.
Reactive Oxygen Species Play an Important Role in the Activation of Heat Shock Factor 1 in Ischemic-Reperfused Heart
Authors: Junichiro Nishizawa, Akira Nakai, Katsuhiko Matsuda, Masashi Komeda, Toshihiko Ban, Kazuhiro Nagata
Journal: Circulation (1999)

Background —The myocardial protective role of heat shock protein (HSP) has been demonstrated. Recently, we reported that ischemia/reperfusion induced a significant activation of heat shock factor (HSF) 1 and an accumulation of mRNA for HSP70 and HSP90. We examined the role of reactive oxygen species (ROSs) in the induction of stress response in the ischemic-reperfused heart. Methods and Results —Rat hearts were isolated and perfused with Krebs-Henseleit buffer by the Langendorff method. Whole-cell extracts were prepared for gel mobility shift assay using oligonucleotides containing the heat shock element. Induction of mRNA for HSP70 and HSP90 was examined by Northern blot analysis. Repetitive ischemia/reperfusion, which causes recurrent bursts of free radical generation, resulted in burst activation of HSF1, and this burst activation was significantly reduced with either allopurinol 1 mmol/L (an inhibitor of xanthine oxidase) or catalase 2×10 5 U/L (a scavenger of H 2 O 2 ). Significant activation of HSF1 was observed on perfusion with buffer containing H 2 O 2 150 μmol/L or xanthine 1 mmol/L plus xanthine oxidase 5 U/L. The accumulation of mRNA for HSP70 or HSP90 after repetitive ischemia/reperfusion was reduced with either allopurinol or catalase. Conclusions —Our findings demonstrate that ROSs play an important role in the activation of HSF1 and the accumulation of mRNA for HSP70 and HSP90 in the ischemic-reperfused heart.
Female Gender Exacerbates Respiratory Depression in Leptin-deficient Obesity
Authors: VSEVOLOD Y. POLOTSKY, JESSICA A. WILSON, MARC C. SMALDONE, ABBY S. HAINES, PATRICIA D. HURN, CLARKE G. TANKERSLEY, PHILIP L. SMITH, ALAN R. SCHWARTZ, CHRISTOPHER P. O'DONNELL
Journal: American Journal of Respiratory and Critical Care Medicine (2001)

Obese females are less predisposed to sleep-disordered breathing and have higher serum leptin levels than males of comparable body weight. Because leptin is a powerful respiratory stimulant, especially during sleep, we hypothesized that the elevated leptin level is necessary to maintain normal ventilatory control in obese females. We examined ventilatory control during sleep and wakefulness in male and female leptin-deficient obese C57BL/6J-Lep ob mice, wild-type C57BL/6J mice with dietary-induced obesity and high serum leptin levels, and normal weight wild-type C57BL/6J mice. Both male and female C57BL/6J-Lep ob mice had depressed hypercapnic ventilatory response (HCVR) in comparison with wild-type animals. In comparison with male C57BL/6J-Lep ob mice, female C57BL/6J-Lep ob mice had reduced HCVR and respiratory drive (a ratio of tidal volume to inspiratory time) both during non-rapid eye movement (NREM) sleep and wakefulness. In contrast, the HCVR did not differ between sexes in wild-type mice during NREM sleep and wakefulness, but was lower in females during REM sleep. Thus, leptin deficiency in female obesity is even more detrimental to hypercapnic ventilatory control during wakefulness and NREM sleep than in obese, leptin-deficient males.
Gastrointestinal Disorders in Americans Returning from Southeast Asia.
Authors: Julian Katz
Journal: Annals of Internal Medicine (1969)

s1 May 1969Gastrointestinal Disorders in Americans Returning from Southeast Asia.Julian KatzJulian KatzSearch for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-70-5-1068_3 SectionsAboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail ExcerptGastrointestinal problems are frequently found in Americans who have been in Southeast Asia. The experience of the gastroenterology section of a military hospital has been reviewed and demonstrates that diseases that are endemic to that tropical region, as well as more familiar diseases, must be considered in the evaluation of these problems. Although infectious diseases are usually diagnosed and treated before return to this country, bacterial and parasitic infections may be found. Malaria exhibits a wide range of gastrointestinal manifestations, including ileus, bleeding, abdominal pain, and diarrhea. These symptoms appearing after return to the United States may be the first... This content is PDF only. To continue reading please click on the PDF icon. Author, Article, and Disclosure InformationAuthors: Julian Katz PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics 1 May 1969Volume 70, Issue 5Page: 1068-1068KeywordsAbdominal painArmed forcesBacterial diseasesDiarrheaHemorrhageInfectious diseasesMalariaParasitic diseasesTropical diseases ePublished: 1 December 2008 Issue Published: 1 May 1969 PDF downloadLoading ...
Temporal relationship between hyperaldosteronism, sodium retention and ascites formation in rats with experimental cirrhosis
Authors: Wladimiro Jiménez, Antonio Martinez-Pardo, Vicente Arroyo, Jordi Bruix, Antoni Rimola, Joan Gaya, Francisca Rivera, Joan Rodés
Journal: Hepatology (1985)

To investigate the role of aldosterone in sodium retention and ascites in cirrhosis, the urinary sodium excretion, sodium balance and urinary excretion of aldosterone–18–glucuronide (U Aid V) were serially measured in 11 rats undergoing cirrhosis induction with carbon tetrachloride (CT) and phenobarbital (CT rats) and in 10 control rats which received phenobarbital. All CT rats developed ascites, seven within the ninth week after starting the program and four within the 10th week. One week before the onset of ascites, CT rats and control rats were different with respect to sodium excretion (1.41 ± 0.15 vs. 1.82 ± 0.1 mEq per day), sodium balance (0.57 ± 0.12 vs. 0.20 ± 0.09 mEq per day) and U Aid V (67.8 ± 9.5 vs. 25.7 ± 1.7 ng per day). These differences were more pronounced within the week in which ascites was detected in CT rats. Before these 2 weeks, both groups did not differ with respect to these parameters. In the 132 urine samples obtained in CT rats, there was a correlation between sodium excretion and U Aid V (r = –0.53; p &lt; 0.001). Twenty–one additional CT rats were divided into two groups. Eleven animals were given spironolactone (20 mg per day s.c. in olive oil) from the 6th week, and 10 only received olive oil. Thirteen weeks after starting the program, all rats not treated with spironolactone had sodium retention and ascites (in five rats, ascites appeared within the ninth week and in five within the tenth week); this occurred in only one animal treated with spironolactone. This difference could not be due to a protective effect of spironolactone against carbon tetrachloride hepatotoxicity since both groups of rats were similar with respect to portal pressure and severity of hepatic lesions. These results are consistent with the concept that aldosterone plays an important but not the sole role in the pathogenesis of ascites in cirrhosis.
Methadone: evidence of accumulation.
Authors: D M Rutherford, K Raymond
Journal: BMJ (1977)

Poor energy intake is certainly not the only cause of growth retardation in chronic renal failure and may indeed not be the most im- portant, for, while growth may improve with supplements, many children still grow poorly in spite of apparently adequate intakes.3Provided the children accept them, feeding energy supplements would still seem to be justified.
England and Wales are among European countries at highest risk of measles epidemic
Authors: Roger Dobson
Journal: BMJ (2008)

Seven European countries, including England and Wales, can expect measles epidemics at some point in the near future, a new report says.

These countries need to strengthen their routine vaccination programmes, target catch-up campaigns at susceptible age groups, such as elderly people, and stress the safety of the measles, mumps, and rubella (MMR) vaccine, say the authors of the report ( Bulletin of the World Health Organization doi: 10.2471/BLT.07.041129).

“It is critical that all countries in Europe achieve and maintain very high vaccine coverage if the target of measles elimination by 2010 in the [WHO] European region is to be reached,” write the authors, from the UK’s Health Protection Agency.

“It is of concern that in seven of the 18 countries [looked at in …
THE INFLUENCE OF FOCAL INFECTIONS
Authors: D. J. McCARTHY
Journal: JAMA (1925)

In studying the influence of focal infections on the human organism, we should fully realize that we are dealing largely with theoretical considerations and not with a definite, demonstrable fact or series of facts subject to a testing process, such as the pathologist or bacteriologist carries out in a laboratory experiment. Any attitude on this subject, necessarily, must be largely a matter of impression on the part of the investigator, tinged somewhat by his state of mind toward the problem under consideration. Notwithstanding that this paper is the result of a careful analysis of 500 of my own cases, all studied in detail by one clinician, the opinions in reference to the influence of the focal infections, even in this group, are the impressions made on me by the results obtained in treatment, and are by no means facts, or to be taken as complete conclusive evidence of the direct
Rib cage dimensions in hyperinflated patients with severe chronic obstructive pulmonary disease.
Authors: M Cassart, P A Gevenois, M Estenne
Journal: American Journal of Respiratory and Critical Care Medicine (1996)

Using computed tomography we assessed rib cage dimensions at the levels of Th4, Th6, Th8, and Th10 in seven supine patients with COPD who were severely obstructed (FEV1, 25 +/- 7% of predicted) and hyperinflated (FRC, 234 +/- 34% of predicted) and seven matched normal control subjects. The midsagittal anteroposterior (AP) diameter, the maximal AP diameter of the right and left hemithorax, and the maximal transverse (T) diameter were measured on scans obtained at relaxed TLC, FRC, and RV. At each volume, AP diameters were invariably 2 to 3 cm greater in patients with COPD than in normal subjects, but no significant differences in T diameters were found. When compared at a given absolute lung volume, T diameters at all thoracic levels and AP diameters at Th4-6 were smaller in patients with COPD than in normal subjects; in contrast, at Th8-10, AP diameters were similar in the two groups. We conclude that the marked hyperinflation of patients with severe COPD produces complex changes in rib cage dimensions: (1) there is an increase in AP but not in T diameters such that the rib cage adopts a more circular shape; (2) at a given absolute lung volume, AP diameters are smaller in patients with COPD than in normal subjects in the upper but not in the lower portion of the rib cage. These differences in rib cage dimensions may have implications regarding respiratory muscle length and function in patients with COPD.
Efficacy of topical non-steroidal anti-inflammatory drugs in the treatment of osteoarthritis: meta-analysis of randomised controlled trials
Authors: Jinying Lin, Weiya Zhang, Adrian Jones, Michael Doherty
Journal: BMJ (2004)

<h3>Abstract</h3> <b>Objective</b> To assess the efficacy of topical non-steroidal anti-inflammatory drugs (NSAIDs) in the treatment of osteoarthritis. <b>Data sources</b> Medline, Embase, Scientific Citation Index, CINAHL, Cochrane Library, and abstracts from conferences. <b>Review methods</b> Inclusion criterion was randomised controlled trials comparing topical NSAIDs with placebo or oral NSAIDs in osteoarthritis. Effect size was calculated for pain, function, and stiffness. Rate ratio was calculated for dichotomous data such as clinical response rate and adverse event rate. Number needed to treat to obtain the clinical response was estimated. Quality of trial was assessed, and sensitivity analyses were undertaken. <b>Results</b> Topical NSAIDs were superior to placebo in relieving pain due to osteoarthritis only in the first two weeks of treatment. Effect sizes for weeks 1 and 2 were 0.41 (95% confidence interval, 0.16 to 0.66) and 0.40 (0.15 to 0.65), respectively. No benefit was observed over placebo in weeks 3 and 4. A similar pattern was observed for function, stiffness, and clinical response rate ratio and number needed to treat. Topical NSAIDs were inferior to oral NSAIDs in the first week of treatment and associated with more local side effects such as rash, itch, or burning (rate ratio 5.29, 1.14 to 24.51). <b>Conclusion</b> Randomised controlled trials of short duration only (less than four weeks) have assessed the efficacy of topical NSAIDs in osteoarthritis. After two weeks there was no evidence of efficacy superior to placebo. No trial data support the long term use of topical NSAIDs in osteoarthritis.
Diagnostic significance of elevated lung/myocardial thallium-201 ratio in chronic congestive heart failure
Authors: Eulogio Martinez, Steven F. Horowitz, Helio Castello, Maerio Castiglioni, Antonio Carvalho, Dircal Almeida, Roberto R Roberti, Manuel Saragoca, Antonio Barbieri
Journal: Journal of the American College of Cardiology (1991)