Intracellular myocardial pH measured in vivo with sustained and reperfused coronary occlusion

Intracellular pH provides an important measure of the adequacy of local tissue perfusion. The purpose of this study was to measure regional intracellular myocardial pH (impH) in the ischemic zone in vivo during experimental canine coronary occlusion, with and without coronary reperfusion. Twenty adult dogs were studied. Ten dogs underwent permanent ligation of the proximal anterior left descending coronary artery (group L), five dogs had coronary reperfusion after 1 hour of total coronary occlusion (group R), and five dogs did not undergo ligation and served as controls (group C). Intracellular myocardial pH was measured by 31phosphorus nuclear magnetic resonance spectroscopy at baseline and then at 15-minute intervals for 6 hours after coronary occlusion (or after sham occlusion in group C). Baseline impH did not differ among groups (group C, 7.22 +/- 0.12 mean +/- standard error of mean; group L, 7.17 +/- 0.07; group R, 7.22 +/- 0.09). During hour 1 of total occlusion, the impH of both groups L (6.58 +/- 0.05) and R (6.55 +/- 0.08) was significantly reduced as compared with the impH of group C (7.3 +/- 0.12; p less than 0.05). At 0 to 1, 1 to 3, and 3 to 5 hours of reperfusion, the impH of group R (7.34 +/- 0.08, 7.27 +/- 0.07, and 7.29 +/- 0.06, respectively for these times) did not differ from group C (7.26 +/- 0.11, 7.21 +/- 0.07, and 7.25 +/- 0.10). At these same times, the impH of group L (6.47 +/- 0.05, 6.57 +/- 0.04, and 6.75 +/- 0.04) was significantly reduced as compared with both groups R and C (p less than 0.05). Thus a severe, persistent regional intracellular myocardial acidosis occurs in the ischemic zone with coronary occlusion but is rapidly corrected by reperfusion within 1 hour.     

Porcine fatty acid synthase: cloning of a complementary DNA, tissue distribution of its mRNA and suppression of expression by somatotropin and dietary protein

A cDNA for porcine fatty acid synthase was isolated and used to examine the tissue distribution of fatty acid synthase mRNA within the pig and to determine the impact of recombinant porcine somatotropin (rpSt) and the level of dietary protein on fatty acid synthase mRNA abundance in pig liver and adipose tissue. A 1.5-kb cDNA representing the thioesterase domain of porcine fatty acid synthase was isolated from a lambda gt 11 liver cDNA library. Northern analysis with total RNA extracted from adipose tissue, liver, heart, lung, kidney and intestine revealed a single major fatty acid synthase mRNA species of 8-9 kb. The amount of fatty acid synthase mRNA in hepatic tissue was 25% of the amount in adipose tissue, which suggests that the liver may be a significant site of fatty acid synthesis in the pig. Fatty acid synthase mRNA abundance was significantly reduced in the adipose tissue (P less than 0.01) and the liver (P less than 0.1) by chronic daily administration (60 micrograms/kg) of rpSt. In addition, increasing the amount of dietary protein decreased (P less than 0.1) the abundance of fatty acid synthase mRNA in adipose tissue but had no effect on liver fatty acid synthase expression. In contrast, the abundance of adipose fatty acid binding protein mRNA was unaffected by rpSt or dietary protein. These data indicate that the reduction in the level of fatty acid synthase mRNA is a factor in the pSt-mediated suppression of fatty acid synthesis in porcine adipose tissue.     

Temporary sequential atrioventricular pacing in myocardial infarction

The loss of atrial contraction can seriously impair cardiac output when complete heart block follows myocardial infarction. We describe two cases in which temporary sequential atrioventricular pacing was lifesaving. The pacemaker used was a previously explanted internal pacemaker. By avoiding the need for an expensive dedicated temporary pacemaker this technique may be more widely applied.     

Estrogen effects on 5-HT1A receptors in hippocampal membranes from ovariectomized rats: functional and binding studies

Chronic treatment (4 days) of ovariectomized rats with estrogen produced a two-fold shift to the left (with no change in the maximal percent inhibition) in the concentration response curve for the inhibition of adenylyl cyclase activity by 5-HT, but did not alter curves for R-PIA (adenosine A1 agonist) or Gpp(NH)p (to activate Gi). Furthermore, estrogen treatment had no effect on the number or affinity of 5-HT1A binding sites labeled with [3H]8-OH-DPAT. These data, when considered with the results of previous studies, suggest that estrogen treatment may selectively enhance 5-HT1A-mediated responses in rat hippocampus.     

Evaluation of speech outcomes following treatment of oral and oropharyngeal cancers

Oral and oropharyngeal cancers are amongst the commonest cancers worldwide and present a major health problem. Owing to their critical anatomical location and complex physiologic functions, the treatment of oral and oropharyngeal cancers often affects important functions, including speech. The importance of speech in a patient’s life can not be overemphasized, as its loss is often associated with severe functional and psychosocial problems and a poor quality of life. A thorough understanding of the speech problems that are faced by these patients and their timely management is the key to providing a better functional quality of life, which must be one of the major goals of modern oncologic practice. This review summarises key methods of evaluation and outcome of speech functions in the literature on oral and oropharyngeal cancer published between January 2000 and December 2008. Speech has been generally overlooked and poorly investigated in this group of patients. This review is an attempt to fill this gap by conducting the first speech-specific review for oral and oropharyngeal cancer patients. We have proposed guidelines for better understanding and management of speech problems faced by these patients in their day-to-day life.     

Tuberculous dactylitis in childhood. The need for continued vigilance

A case of tuberculous dactylitis in a 3-year-old Chinese boy is presented and the radiographic findings and differential diagnosis discussed. Although this is a rare condition, the diagnosis should be considered when a member of the immigrant community presents with an unusual bony lesion.     

How accurate are doctors,nurses and medical students at predicting life expectancy?

BackgroundPredicted patient life expectancy, based on a patient's medical history, is an important component of medical decision making. This study therefore aimed to determine the consistency, accuracy and precision with which doctors, nurses and medical students predict life expectancy (LE).Methods20 doctors, 20 nurses and 20 medical students (4th and 5th year) independently examined 70 hypothetical patient case scenarios containing age, sex and comorbidity; this included 13 duplicate scenarios. Accuracy and consistency of prediction was assessed by comparison with statistical LE estimates generated using evidence-based actuarial and life insurance industry methods in collaboration with a team of professional actuaries.ResultsDoctors, nurses and medical students underestimated LE by a mean (95% confidence interval) of ? 1.46 (? 0.31 to ? 2.61), ? 1.79 (? 0.52 to ? 3.06) and ? 2.24 (? 1.16 to ? 3.32) years with an equivalent root mean squared error (RMSE) of 4.74, 5.49 and 5.08 years respectively. LE predictions were equal to actuarial LE in less than 10% of cases and accurate to within 25% of actuarial LE in less than 45% of cases. Intra-observer reliability was 91%, 85% and 87% for doctors, nurses and medical students respectively. Inter-observer reliability was 66%, 57% and 57% for the three groups.ConclusionDoctors, nurses and medical students were inconsistent, inaccurate and imprecise in their prediction of LE with a tendency toward underestimation. This may lead to patients being managed inappropriately. There is a need for improved training and objective outcome prediction models.