Redistribution of collateral blood flow from necrotic to surviving myocardium following coronary occlusion in the dog

Early changes in collateral blood flow after acute coronary occlusion may be critical for survival of ischemic myocardium. We used 15-mum radioactive microspheres to study myocardial blood flow in thoracotomized dogs 10 minutes and 24 hours after occlusion of the left anterior descending coronary artery (LAD). The ischemic area was delineated by dye injected into the distal artery, and indentification of potentially ischemic samples was confirmed by a newly developed technique in which microspheres were excluded from the normally perfused LAD. Layers were separated into necrotic or normal as defined by gross inspection and confirmed by histological examination and creatine phosphokinase assay. Infarction always involved endocardial layers and extended toward the epicardium. Average myocardial blood flow in 48 necrotic samples from 16 dogs either remained low (less than 0.05 ml/min g-1) or declined, falling from 0.11 +/-0.02(SE) at 10 minutes to 0.05 +/-0.01 ml/min g-1 at 24 hours (P less than 0.001). In contrast, in the 32 normal-appearing samples which were ischemic at 10 minutes, flow increased from 0.24 +/-0.03 to 0.39 +/-0.04 ml/min g-1 (P less than 0.001). Flow in control myocardium was 1.43 +/-0.12 and 1.04 +/-0.07 ml/min g-1, respectively. Peripheral mean coronary arterial pressure increased from 26 +/- 3 to 35 +/- 3 mm Hg, largely because of enlargement of collateral vessels; collateral conductance calculated from retrograde flow in 14 dogs increased from 0.023 +/- 0.005 after occlusion to 0.051 +/- 0.009 ml/min mm Hg-1 24 hours later (P less than 0.001). Thus, coronary collateral blood flow is redistributed from necrotic endocardial layers to surviving epicardial ones. In combination with a developing collateral supply this process may be essential for sparing myocardium after coronary occlusion.     

Alveolar bone levels in AIDS and HIV seropositive patients and in control subjects

Alveolar bone levels were studied from intraoral radiographs of 24 non-hospitalized patients with AIDS, 17 HIV seropositive subjects, and 39 matched control subjects. The AIDS/HIV subjects were seeking dental care in a faculty practice. The matched control subjects came from those non-HIV-infected patients seeking dental care at the University of Washington. Magnified intraoral radiographs were used to assess the distance between the cemento-enamel junction (CEJ) and the alveolar bone level (BL). The extent of vertical defects and furcation invasions was also assessed. The mean age of the AIDS, HIV, and control subjects was 38.9 +/- 6.6 years, 37.1 +/- 7.6, and 39.9 +/- 5.6, respectively, and was not statistically different. Among the AIDS patients, 75% were smokers, while 88.2% of the HIV subjects were cigarette smokers. Therefore, the matched control subjects were also smokers to the same extent. The mean difference in distance CEJ-BL was 0.1 mm (mesial) and 0.3 mm (distal) and greater in the HIV/AIDS group than in the control group, but not statistically different. No vertical defects > or = 3.0 mm were found in 69.2% of the control subjects and in 58.5% of the combined HIV/AIDS group. None of the HIV/AIDS subjects had more than 5 defects > 3.0 mm, while 7.6% of the control subjects had such defects. Significant associations were found between smoking and extent of alveolar bone loss (distance) (P < 0.001) as well as the number and extent of vertical defects (P < 0.01), but were not associated with HIV status. The extent of furcation invasions, as read radiographically, did not differ between groups. In conclusion, smoking but not HIV status was the primary factor for alveolar bone loss.     

Immunoglobulin G and complement C3 levels in pregnancy induced hypertension

A specific assay for the quantitative determination of the new antibiotic azithromycin in a low volume of human serum is described. The assay uses on-line high-performance liquid chromatography (HPLC) and atmospheric pressure chemical ionization mass spectrometry (HPLC-APCI). Deuterium-labeled azithromycin was synthesized and used as the internal standard of the assay. The drug and the internal standard are extracted from 50 microliters of serum, and aliquots are injected onto a standard reverse-phase HPLC column. The effluent from the HPLC column at 1 ml/min is introduced into the atmospheric pressure source of a SCIEX API III mass spectrometer. Azithromycin concentrations in serum are determined by the selected monitoring of the protonated molecular ions of the drug and the internal standard. Our assay yields accurate and precise results over the range 10 ng/ml to 250 ng/ml. The correlation between the assay and a standard HPLC-electrochemical method, requiring a larger volume of serum, has been determined. The two methods showed excellent agreement. Because of its low volume requirement, our HPLC-APCI assay can be substituted for the standard assay for the investigation of azithromycin pharmacokinetics in children.     

Discipline responses: Influences of parents' socioeconomic status, ethnicity, beliefs about parenting, stress, and cognitive-emotional processes.

Direct and indirect precursors to parents' harsh discipline responses to hypothetical vignettes about child misbehavior were studied with data from 978 parents (59% mothers; 82% European American and 16% African American) of 585 kindergarten-aged children. SEM analyses showed that parents' beliefs about spanking and child aggression and family stress mediated a negative relation between socioeconomic status and discipline. In turn, perception of the child and cognitive-emotional processes (hostile attributions, emotional upset, worry about child's future, available alternative disciplinary strategies, and available preventive strategies) mediated the effect of stress on discipline. Similar relations between ethnicity and discipline were found (African Americans reported harsher discipline), especially among low-income parents. Societally based experiences may lead some parents to rely on accessible and coherent goals in their discipline, whereas others are more reactive. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Departmental audit in surgical anatomical pathology

Chronic obstructive pulmonary disease (COPD) is the result of many years of accelerated decline in lung function in susceptible cigarette smokers. Although risk factors for the susceptibility of smokers to COPD have been established, there are still large gaps in our knowledge of the biological basis for these risk factors and of how to identify individuals at risk. COPD is the fourth leading cause of death and, in contrast to other major chronic diseases in the United States, has not shown declines in mortality over the past 20 years. Mortality trends reflect patterns of initiation of cigarette smoking that occurred 30 to 50 years previously. Current mortality trends indicate that COPD mortality may be leveling off among white males, but will continue to increase among women, African-Americans, and the elderly. Recent studies indicate that early identification of individuals with airflow obstruction and smoking intervention can halt the progression of COPD, but widespread screening and intervention programs have not yet been established.     

Recombinant human granulocyte colony-stimulating factor (filgrastim) following high-dose chemotherapy and peripheral blood progenitor cell rescue in high-grade non-Hodgkin's lymphoma: clinical benefits at no extra cost

In order to evaluate the potential clinical and economic benefits of granulocyte colony-stimulating factor (G-CSF, filgrastim) following peripheral blood progenitor cells (PBPC) rescue after high-dose chemotherapy (HDCT), 23 consecutive patients aged less than 60 years with poor-prognosis, high-grade non-Hodgkin's lymphoma (NHL) were entered into a prospective randomized trial between May 1993 and September 1995. Patients were randomized to receive either PBPC alone (n = 12) or PBPC+G-CSF (n = 11) after HDCT with busulphan and cyclophosphamide. G-CSF (300 microg day[-1]) was given from day +5 until recovery of granulocyte count to greater than 1.0 x 10(9) l(-1) for 2 consecutive days. The mean time to achieve a granulocyte count > 0.5 x 10(9) l(-1) was significantly shorter in the G-CSF arm (9.7 vs 13.2 days; P<0.0001) as was the median duration of hospital stay (12 vs 15 days; P = 0.001). In addition the recovery periods (range 9-12 vs 11-17 days to achieve a count of 1.0 x 10(9) l[-1]) and hospital stays (range 11-14 vs 13-22 days) were significantly less variable in patients receiving G-CSF in whom the values clustered around the median. There were no statistically significant differences between the study arms in terms of days of fever, documented episodes of bacteraemia, antimicrobial drug usage and platelet/red cell transfusion requirements. Taking into account the costs of total occupied-bed days, drugs, growth factor usage and haematological support, the mean expenditure per inpatient stay was pound sterling 6500 (range pound sterling 5465-pound sterling 8101) in the G-CSF group compared with pound sterling 8316 (range pound sterling 5953-pound sterling 15,801) in the group not receiving G-CSF, with an observed mean saving of 1816 per patient (or 22% of the total cost) in the G-CSF group. This study suggests that after HDCT and PBPC rescue, the use of G-CSF leads to more rapid haematological recovery periods and is associated with a more predictable and shorter hospital stay. Furthermore, and despite the additional costs for G-CSF, these clinical benefits are not translated into increased health care expenditure.     

Blockade of tachykinin NK1 receptors by CP-96345 enhances dopamine release and the striatal dopamine effects of methamphetamine in rats

The nonpeptide, tachykinin NK1 receptor antagonist, CP-96345, permits the study of the physiological role of extrapyramidal substance P systems. Using microdialysis, we observed that locally applied CP-96345 (200 nM) caused a significant increase in dopamine release in the striatum as well as substantially enhancing striatal dopamine release caused by a low dose of methamphetamine (0.5 mg/kg s.c.). In addition, multiple systemic administrations of CP-96345 almost doubled the dopamine-mediated responses of the striatal neurotensin and dynorphin systems to high doses of methamphetamine (10 mg/kg/dose s.c.). Our findings suggest that the physiological role of substance P released in the striatum is to decrease the activity of the nigrostriatal dopamine pathway.     

On the choice of a production control system

This paper deals with a problem to develop ‘factory automation systems’ which harmonize companies’ needs with workers’ desires. Two kinds of indices and methods of survey are proposed on the basis of the ‘fusion system concept’. One is that of the state of workers’ desires which are based on the ‘stimulus-response model’, the other is that of situations where ‘factory automation’ is implemented in a workshop. The effects of ‘factory automation’ on workers’ desires are clarified in a study of Japanese manufacturing industries in 1983. As a result of this investigation, some problems can be pointed out which should be solved in the future to develop ‘factory automation systems’.