Bioenergetics and control of oxygen consumption in the in situ rat heart

Control of respiration by products of ATP hydrolysis was examined in the in situ rat heart using a purpose-built nuclear magnetic resonance (NMR) coil. The in situ ratio of phosphocreatine to ATP concentrations ([PCr]/[ATP]) was 2.30 +/- 0.05, free Mg2+ concentration ([Mg2+]) was 0.57 mM, and cytosolic pH was 7.35 +/- 0.03 (n = 7). Basal inorganic phosphate concentration ([Pi]) was below NMR detection but was estimated to be 0.83 mM. The [ATP]/[ADP] [Pi] ratio, free ADP concentration ([ADP]), and free energy of ATP hydrolyses (delta GATP) were calculated to be 700,000 +/- 78,000 M-1, 18 +/- 3 microM, and -63.93 +/- 0.33 kJ/mol in situ, respectively (n = 7). In contrast, in the Langendorff perfused rat heart [ATP]/[ADP] [Pi] was only 76,140 +/- 12,830 M-1, [ADP] was 65 +/- 9 microM, and delta GATP was -59.92 +/- 0.48 kJ/mol (n = 7), all indicative of a lower energy state in vitro. Epinephrine infusion in situ (0.9 microgram.min-1.kg-1) increased the rate-pressure product 2.05-fold. During stimulation [ATP] was stable at 97 +/- 3% signal intensity, [PCr] declined by 25%, and [Pi] increased to 1.83 mM. Cytosolic pH was 7.27 +/- 0.01 and [Mg2+] was 0.64 +/- 0.05 mM. [PCr]/[ATP] declined to 1.83 +/- 0.13, and [ATP]/[ADP] [Pi] fell to 108,000 +/- 15,000 M-1. delta GATP only fell marginally to -59.56 +/- 0.49 kJ/mol. Free [ADP] increased threefold to 55 +/- 10 microM. Infusion of 2.8 +/- 0.5 microgram.min-1.kg-1 epinephrine increased the rate-pressure product 2.7-fold, further reduced [ATP]/[ADP] [Pi] (5% of basal), and elevated [ADP] more than fourfold without changing [ATP]. We conclude that the in situ heart is highly energetic compared with isolated perfused hearts and operates at a different metabolic "set-point." Because free [ADP] and [Pi] in situ approximate apparent Michaelis constants for mitochondrial respiration in vitro and increase with increased cardiac work, we conclude that each fulfills the criteria for the kinetic control of O2 consumption in the in situ rat myocardium.

Mobile cardiac catheterization registry: report of the first 1,001 patients

The purpose of this study was to evaluate prospectively the efficacy and safety of mobile cardiac catheterization. Mobile cardiac catheterization was introduced into clinical practice in 1989, but there has been no systematic study of its performance and safety. A registry was established in 1989 to monitor outcomes with mobile cardiac catheterization and is reported here. Patients were screened for eligibility for mobile cardiac catheterization using the joint AHA/ACC criteria for outpatient angiography. Eligible patients underwent mobile catheterization at eight hospitals within 120 miles of the base tertiary center. Helicopter evacuation services were available at each mobile site. The indications, findings, dispositions, and complications of mobile cardiac catheterization were recorded by means of a checklist, telephone follow-up and chart review. A total of 1,001 consecutive patients were entered into the registry in the first 20 months of operation, including 436 females and 565 males aged 22 to 84 years. Angina (Canadian Classes II-IV) was the most frequent primary indication for catheterization (46.4%), followed by atypical chest pain (36.9%), or a positive exercise stress test (25.6%). Infrequent indications for catheterization included a history of myocardial infarction (5.6%), congestive heart failure (7.1%), arrhythmias (4.1%), and valvular heart disease (0.7%). Catheterization was accomplished in 99.9% of patients. Angiographically normal studies were observed in 22.8%, and mild (< or = 50%) coronary artery disease in 13.6% of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Comprehensive drug and alcohol treatment programming: a bold new approach

We have witnessed, in the latter half of the 20th century, significant revisions in the manner in which medical, psychiatric, and forensic services are delivered. Specifically, it appears that a wide range of treatment services are moving from modes of intervention that are dominated by primary institutional arrangements towards decentralized, community-based models of care. Missouri's CSTAR program represents a similar shift in alcohol and drug treatment. The CSTAR program provides an array of intensive community services that replaces hospital and residential services. In addition, community-based case management services promote social as well as medically based interventions. Parallels between the CSTAR model and the development of Community Support Services in psychiatric care are offered.

Identification and characterization of a novel Bacillus thuringiensis delta-endotoxin entomocidal to coleopteran and lepidopteran larvae

A new class of Bacillus thuringiensis delta-endotoxins, or insecticidal control proteins (ICPs), is defined by an apparently cryptic protein with a unique primary structure and novel entomocidal specificity for certain coleopteran and lepidopteran species. The discovery of a new group of ICPs will extend the use of this natural insecticide in integrated pest-management systems.

New alternatives in gallstone treatment

Within the past few years, a number of new treatment modalities for gallbladder stones have become available. Laparoscopic cholecystectomy has proved as safe as traditional surgical cholecystectomy, without the discomfort and lengthy recuperation associated with a large abdominal incision. Several other new treatments also have been investigated, including percutaneous cholecystolithotomy, peroral drug chemolysis, extracorporeal shock wave lithotripsy, and methyl-tert-butyl ether lavage. The relative merits and disadvantages of these treatments, compared to each other and to standard cholecystectomy, are described herein.

Periprosthetic knee sepsis. The role of irrigation and debridement

Thirty-three infected total knee arthroplasties were treated by irrigation, debridement, and intravenous antibiotics. These cases were retrospectively reviewed with an average follow-up period of 4.5 years. There were 12 revisions and 21 primary arthroplasties in the series. Thirty-two knees were openly irrigated and debrided, and one was arthroscopically treated. In 20 of 33 knees, infection recurred--a reinfection rate of 61%. The authors attempted to identify factors influencing success and failure of infection eradication. There was a statistically significant improvement in the success rate of knees irrigated and debrided within four weeks of index surgery (p less than .05). No statistically significant correlation was found between success and failure with regard to gender, age, preoperative diagnosis, previous surgery, length of intravenous antibiotics, or time from clinical symptoms to debridement. The authors believe that irrigation and debridement have a role in the immediate postoperative period. Caution should be used in periprosthetic knee infection appearing greater than four weeks from index surgery.

Palliative care in a general teaching hospital. 2. Establishment of a service

OBJECTIVE

To assess the first year of operation of a palliative care service in a general teaching hospital.

DESIGN, SETTING, PATIENTS

A retrospective analysis of 241 terminally ill patients referred to the Austin Hospital Palliative Care Service during its first year of operation.

MAIN OUTCOME MEASURES

The occurrence and relief of pain, the occurrence and management of social and psychological problems, involvement of allied health services and the place of death.

MAIN RESULTS

Unrelieved pain was the most frequent medical problem but, with appropriate medical management as well as input from other members of the multidisciplinary team, all patients achieved satisfactory pain control. The occurrence and severity of social and psychological problems was greater than expected. Most of the patients were discharged home and referred to domiciliary palliative care services; one-quarter of patients were able to die at home, one-third died in an inpatient hospice, and the remainder died in hospital.

CONCLUSIONS

The Service was able to achieve most of its stated aims and has generated a much improved appreciation of the palliative care needs of patients with terminal illness and their families within the Hospital. A multidisciplinary approach to the management of terminally ill patients is crucial, and this Service has been successful despite limited staffing because of the willing involvement of other Units and Services in the Hospital. The difficulties inherent in the evaluation of a palliative care program (quality of life, cost-effectiveness) are discussed.

Caregiver's anticipatory grief in dementia: a pilot study

Twenty-seven wives who care for their spouses suffering from dementia completed the Anticipatory Grief Scale (AGS) and the Hopkins Symptom Checklist--SCL-90-R. The alpha coefficient for the AGS was 0.84, indicating good internal consistency. The AGS was also positively and significantly correlated (p less than 0.001) with the depression, anxiety, and hostility dimensions of the SCL-90-R, demonstrating good validity. The study explores bereavement issues of spouses of patients with dementia and provides preliminary findings on a new instrument to measure anticipatory grief.

The Relationship Between Changing Answers and Performance on Multiple-Choice Nursing Examinations

The purpose of this study was to investigate answer changing among undergraduate nursing students on multiple choice examinations. The sample included 284 students enrolled in the upper division of a baccalaureate nursing program. Answer sheets were examined for erasures to determine the number and direction of changes made. The results of the study indicated that most students changed at least one answer. Analysis of the data indicated that there was a significant difference between changing from wrong to right versus changing from right to wrong. About 55.3% gained points as a result of changing answers while only 18.3% lost points.

Activity of interneurons within the L4 spinal segment of the cat during brainstem-evoked fictive locomotion

Extracellular recordings from interneurons located in the L4 spinal segment were made during fictive locomotion produced by electrical stimulation of the mesencephalic locomotor region (MLR) in the paralysed decerebrate cat. Only interneurons within the L4 segment which received group II input from quadriceps, sartorius or the pretibial flexor muscle afferents and which had axonal projections to motor nuclei in L7 were selected for analysis. During the fictive step cycle two thirds of these interneurons fired action potentials during the time of activity in the ipsilateral hindlimb flexor neurograms. These cells were also less responsive to peripheral input during the extension phase of the fictive locomotion cycle. The remaining one third of the interneurons examined were not rhythmically active during locomotion. The possible contributions of the midlumbar interneurons to motoneuron activity during locomotion are discussed.

A simple field test for assessing salt balance in heat-stressed miners

A simple colorimetric test for urinary chloride (Fantus test) corrected for urine specific gravity (measured by refractometry) enabled 24-hour urinary sodium excretion rates to be predicted accurately from a single spot sample of urine. In 29 acclimatized miners working in an environment in excess of 40 degrees C, salt-conserving mechanisms, involving renin and aldosterone, were not active until the urinary sodium excretion rate fell below 50 mmol/24 h. A predicted sodium excretion rate greater than 50 mmol/24 h indicates that dietary sodium supplementation is not necessary.

A sensitive and continuous fluorometric assay for phospholipase A2 using pyrene-labeled phospholipids in the presence of serum albumin

Phospholipase A2 activity can be determined fluorometrically in the presence of serum albumin using phospholipids labeled at the sn-2-acyl position with 10-pyrenyldecanoic acid. In the water reaction medium 10-pyrene phospholipids form vesicles and the monomer fluorescence of the pyrene is negligible due to pyrene-pyrene interaction. Upon phospholipid hydrolysis 10-pyrenyldecanoic acids are produced and tightly bind to albumin so that a monomer pyrene fluorescence is observed. We obtained an excellent parallelism between hydrolysis determined by a classical extraction method and that followed by direct and continuous spectrofluorometric recording of the monomer emission of pyrene. This assay can measure picomole amounts of phospholipids hydrolyzed per minute so that picogram quantities of phospholipases A2 from pancreas or from venoms can be measured. Phospholipase activity remains proportional to enzyme concentration over three orders of magnitude. The method can be used to quantify the phospholipase A2 activity of crude extracts of low specific activity.

Research skills and the research environment: a needs assessment of allied health faculty

Allied health faculty are expected to successfully compete with other academic faculty in the research arena, yet many feel unprepared for this role. Most faculty have been trained as clinicians and, thus, bring to academe few skills in research design and methodology. A national study was conducted to assess the research skills and the research milieu of allied health faculty across eleven disciplines. Data are presented from 2,187 survey responses. Unmet needs included skills in obtaining funding, statistical analysis of the data, and publishing research results. Major barriers to research included the undervaluing of research relative to education and service, the lack of financial and administrative support, the absence of professional resources, and the generally low priority given research. Faculty with earned doctorates perceived their research environments more favorably and had fewer gaps in research skills than did faculty with a bachelor's or master's degree.

Research productivity profile of allied health faculty

Many allied health faculty are expected to obtain graduate degrees and engage in scholarly activity to advance knowledge in their professions and fulfill the research mission of their academic institution. A national study of ten allied health disciplines was conducted to assess the level of allied health research productivity and to determine the relationship between the amount of research and faculty characteristics. Research productivity included the number of major paper presentations and research publications, number of times served as project principle investigator, and the time devoted to research per week. Faculty characteristics were the type of employing institution, and the academic degree, rank, and tenure status of the faculty member. Data from 2,187 survey respondents indicated that faculty who are employed by four-year research universities, possess earned doctorates, hold the rank of professor, and are tenured had significantly higher levels of research productivity.

Lipocortin inhibition of extracellular and intracellular phospholipases A2 is substrate concentration dependent

Hydrolysis of Escherichia coli membrane phospholipids by pancreatic phospholipase A2 was inhibited by lipocortin from human monocytes in a substrate dependent manner. Inhibition was completely overcome at substrate concentrations above 250 microM. Lipocortin also inhibited partially purified preparations of two intracellular phospholipases A2 isolated from rat liver mitochondria and rat platelets when these enzymes were assayed at low micromolar concentrations of phosphatidylethanolamine. Inhibition gradually decreased with increasing substrate concentrations both for pancreatic and platelet phospholipase A2 and became completely abolished above 15 and 50 microM phosphatidylethanolamine, respectively.

Modified latissimus dorsi and teres major transfer for external rotation deficit of the shoulder

Variable impairment occurs following birth associated brachial plexus injury. Muscle transpositions have evolved in response to patient need for functional reconstruction. Loss of external rotation limits the ability to perform activities with the arm in an overhead position. A modification of the combined latissimus dorsi and teres major transfer is described by means of which increased excursion of the transfer may be achieved.

Reversal of cholera toxin-induced secretion in rat ileum by luminal berberine

The effect of luminal berberine hydrochloride concentration on cholera toxin-induced water and electrolyte secretion and on normal water and electrolyte transport was determined in vivo in the cannulated, perfused rat ileum using [14C]polyethylene glycol as a nonabsorbable marker. Berberine reduced the cholera toxin-induced secretion of water, Na, Cl, and calculated residual ion (primarily HCO3) in a concentration-dependent manner. The effect of berberine on cholera toxin-induced ileal secretion was evident 60-80 min after exposure and was reversed 60-80 min after removal of berberine from the perfusate. Mild changes in mucosal histology (villous tip edema) due to cholera toxin were also reversed by berberine. Berberine did not significantly alter normal ileal water and electrolyte transport.