Twenty four hour heart rate variability: effects of posture, sleep, and time of day in healthy controls and comparison with bedside tests of autonomic function in diabetic patients

Heart rate variability was measured in 77 healthy controls and 343 diabetic patients by a count of the number of beat-to-beat differences greater than 50 ms in the RR interval during a 24 hour ambulatory electrocardiogram. In the healthy controls the lower 95% tolerance limits for total 24 hour RR interval counts were approximately 2000 at age 25, 1000 at 45, and 500 at 65 years. Six controls confined to bed after injury had normal 24 hour patterns of RR counts, while eight other controls showed loss of diurnal variation in both heart rate and RR counts during a period of sleep deprivation. RR counts in ten controls on and off night duty increased during sleep whenever it occurred. Nearly half (146) the 343 diabetic patients had abnormal 24 hour RR counts. The percentage of abnormal RR counts increased with increasing autonomic abnormality assessed by a standard battery of tests of cardiovascular autonomic function. A quarter of those with normal cardiovascular reflex tests had abnormal 24 hour RR counts. There were close correlations between 24 hour RR count results and the individual heart rate tests (r = 0.6). The assessment of cardiac parasympathetic activity by 24 hour RR counts was reliable. The diurnal variations in RR counts seen in the controls were probably related to sleep rather than either posture or time of day. The method was more sensitive than conventional tests of cardiovascular reflexes.

Pathophysiology of dynamic cardiomyoplasty: a clinico-pathological case study

A 58-year-old man with end-stage ischemic cardiomyopathy underwent dynamic cardiomyoplasty. "On" and "off" studies with the cardiac assist device failed to show any significant hemodynamic changes despite improvement in functional status. The patient's late postoperative course was complicated by two episodes of acute pulmonary edema followed by cardiac arrest. These events were precipitated by ventricular tachycardia. The last episode led to myocardial infarction requiring diastolic counterpulsation and inotropic support. He died 4 1/2 months following the cardiomyoplasty. Postmortem findings revealed an anterior left ventricular infarct with aneurysm. There was fusion of skeletal muscle to the epicardium with minimal fibrosis and atrophy. The latissimus dorsi (LD) flap was viable, but myofibrillar ATPase stain revealed incomplete transformation. Several clinical observations have emerged from the early experience with dynamic cardiomyoplasty: (1) Important arrhythmias and cardiac arrest compromise the vascular supply and thus power of the muscular flap; (2) Resting ejection fraction does not correlate with exercise tolerance, therefore, other parameters must be sought to explain improved functional status; (3) Uniform muscle transformation in humans may be unpredictable with current clinical stimulation protocols. The conformation of LD to the epicardium underscores a potential remodeling phenomenon which may ultimately spare the diseased myocardium by altering its oxygen supply/demand ratio and thus the natural history.

Epidural anesthesia for obstetrics after spinal surgery

The experience of 18 patients with previous spinal surgery who requested epidural anesthesia for obstetric pain was reviewed. Three received epidural anesthetics in two separate pregnancies, producing a total of 21 attempts at epidural anesthesia. All were initiated during labor and three were later extended for Cesarean delivery. Continuous lumbar epidural anesthesia was successfully established in 20 of 21 attempts. Ten were performed easily on the first attempt. There were excessive local anesthetic requirements and/or a patchy block for the remaining 11 attempts. The only complication that could be attributed to the attempts at epidural anesthesia was temporary low back pain in two patients with multiple attempts. No complications were noted on long-term follow-up. Our data, therefore, suggest that epidural anesthesia is safe and generally effective in obstetric patients with previous spinal surgery.

Measles antibody: reevaluation of protective titers

A school blood drive before a measles outbreak permitted correlation of preexposure measles antibody titers with clinical protection using the plaque reduction neutralization (PRN) test and an EIA. Of 9 donors with detectable preexposure PRN titer less than or equal to 120, 8 met the clinical criteria for measles (7 seroconfirmed) compared with none of 71 with preexposure PRN titers greater than 120 (P less than .0001). Seven of 11 donors with preexposure PRN titers of 216-874 had a greater than or equal to 4-fold rise in antibody titer (mean, 43-fold) compared with none of 7 with a preexposure PRN titer greater than or equal to 1052 (P less than .02). Of 37 noncases with preexposure PRN titer less than 1052, 26 (70%) reported one or more symptoms compared with 11 (31%) of 35 donors with preexposure PRN titers greater than or equal to 1052 (P less than .002). By EIA, no case had detectable preexposure antibody; the preexposure geometric mean titer of asymptomatic donors (220) was not significantly higher than that of symptomatic donors who did not meet the clinical criteria for measles (153) (P = .10). The study suggests that PRN titers less than or equal to 120 were not protective against measles disease and illness without rash due to measles may occur in persons with PRN titers above this level.

Phase I trial of intraperitoneal recombinant interleukin-2/lymphokine-activated killer cells in patients with ovarian cancer

Ten patients with ovarian cancer refractory to conventional therapy were treated with intraperitoneal (i.p.) recombinant interleukin-2 (rIL-2) and lymphokine-activated killer cells (LAK). The 28-day protocol consisted of 6 priming i.p. rIL-2 infusions on days 0, 4, 6, 8, 10, and 12. Leukapheresis was performed for mononuclear cell collection on days 15, 16, 17, and 18 and lymphokine-activated killer cells were given i.p. with the rIL-2 on days 19 and 21. Three additional i.p. rIL-2 infusions were given on days 23, 25, and 27. Three dose levels of rIL-2 were tested: 5 X 10(5), 2 X 10(6), and 8 X 10(6) units/m2 body surface area. The dose-limiting toxicity was abdominal pain secondary to ascites accumulation with significant weight gain. Other toxic effects included decreased performance status, fever, nausea and vomiting, diarrhea, and anemia. Peripheral lymphocytosis and eosinophilia were seen at all dose levels. The maximum tolerated dose is 8 X 10(6) units/m2/dose. Peripheral and peritoneal IL-2 levels were measured with a bioassay using an IL-2-dependent cell line. At the highest dose level, serum IL-2 was greater than 10 units/ml for 18 h. After the first infusion, a 2-log dilution of the i.p. IL-2 was measured in the serum. In the postleukapheresis i.p. IL-2-dosing period less IL-2 was detected in the serum than in the earlier i.p. IL-2-priming period. The induction and persistence of LAK activity were studied. Peritoneal LAK activity was detected as early as 4 days after the first i.p. infusion, by day 11 in all evaluable patients, and persisted for the 6-day interval between priming IL-2 and LAK/IL-2 infusion. Peritoneal lytic activity persisted until day 28 in 5 tested patients. These peritoneal cells retained lytic activity 48 h in culture medium without rIL-2 present. Peritoneal LAK activity correlated with the percentage of mononuclear cells and the percentage of CD56-positive mononuclear cells in the peritoneum. The yield of peripheral lymphocytes after the six i.p. priming doses of rIL-2 correlated with the dose level of rIL-2 infused. Peripheral blood LAK activity showed a minimal, however progressive, increase during the treatment protocol. LAK activity could be enhanced if rIL-2 was present during the 4-h assay. These studies indicate that i.p. rIL-2 infusion induced durable regional LAK activity and primes peripheral blood cells for LAK activity if exposed briefly to additional IL-2.

Identification of a nucleocapsid protein as a specific serological marker of human herpesvirus 6 infection

Enveloped whole virions and nucleocapsids of human herpesvirus 6 (HHV-6) strain Z29 were purified from supernatant fluids of infected human cord blood lymphocytes by filtration through polyvinylpyrrolidone-treated filters, banding on a Nycondenz step gradient, and centrifugation through two successive continuous sucrose gradients. More than 20 proteins ranging in molecular weight from less than 30,000 to more than 200,000 were identified in preparations of purified whole virions labeled with [35S]methionine and [35S]cysteine. Immunogenic virion proteins of HHV-6 were identified in immunoblot assays with human immune sera, immune sera generated from mice immunized with purified whole virions or purified nucleocapsids, and a monoclonal antibody generated from a mouse immunized with purified nucleocapsids. The sera and the monoclonal antibody reacted strongly with a 101-kilodalton protein in the immunoblots, suggesting that the protein is a component of the nucleocapsid. Human sera lacking HHV-6-specific antibodies and seropositive for one or more of the other human herpesviruses failed to react with this protein, indicating that it is a specific serologic marker for HHV-6 infection.

Large volumes of apple juice preoperatively do not affect gastric pH and volume in children

The effect on gastric pH and volume of 0, 6 and 10 ml.kg-1, of apple juice given 2.5 hours before surgery to children aged five to ten years was investigated in this prospective, randomized, single-blind study. Gastric contents were aspirated after induction of anaesthesia, and the volume measured. The pH of the gastric aspirate was then assessed using pH paper. Neither gastric volume nor pH immediately following the induction of general anaesthesia were significantly different among the three groups. Gastric volumes after 0, 6 and 10 ml.kg-1, of juice averaged (mean +/- SD) 0.45 +/- 0.31, 0.66 +/- 0.79 and 0.71 +/- 0.76 ml.kg-1, respectively; gastric pH averaged 1.7 +/- 0.6, 1.7 +/- 0.6 and 1.8 +/- 0.8, respectively. On the basis of questions asked immediately before induction of anaesthesia, patients who drank 6 ml.kg-1 of apple juice had decreased thirst and were less irritable and upset before anaesthesia than those who had not (P less than 0.05). It is concluded that drinking large volumes of clear apple juice 2.5 hours before scheduled surgery does not have a measurable effect on gastric volume and pH and may offer benefits such as improved patient comfort.

Phenotypic characterization of bovine lymphoblastoid cell lines

Cytochemical and immunological markers were used to phenotype the bovine lymphoblastoid cell lines BL-3*, EBL-1, and EBL-2. Southern blot experiments were also performed to test these lines for the presence of proviral bovine leukemia virus (BLV). The BL-3* cell line, originally derived from a case of sporadic bovine leukosis (non BLV-associated) but later infected with BLV in vitro, was found to contain BLV provirus and expressed the BLV-encoded envelope glycoprotein BLV-gp51. BL-3* cells express surface IgM and cytoplasmic IgM as well as class II antigens, and greater than 95% were negative for the T-cell markers B26A, sheep erythrocyte (E) receptors and alpha-naphthyl butyrate esterase (alpha-NB). BL-3* thus appears to be B-cell derived. EBL-1 and EBL-2 were derived from cows with enzootic bovine lymphosarcoma; however, these cell lines were found not to be infected with BLV. Phenotypically, EBL-1 and EBL-2 are mature T-cells, as they were positive for the B26A epitope, alpha-NB, and E receptors. These cell lines also express class II major histocompatibility antigens, indicating an activated state. The T-cell phenotype of EBL-1 and EBL-2 raises interesting questions concerning the possible role of other retroviruses and non BLV-infected transformed T-cells in the development of EBL tumors.

Acute effects of doxorubicin on human left ventricular systolic and diastolic function

Although the long-term cardiotoxic effects of cumulative doses of doxorubicin are well established, the short-term effects on cardiac function are uncertain. Therefore we examined the short-term effects of doxorubicin on left ventricular systolic and diastolic function following a total of 56 doses of doxorubicin in 15 patients with normal resting left ventricular function. Resting radionuclide ventriculography was performed 1 hour before and 4 hours after each dose of doxorubicin. Left ventricular ejection fraction increased significantly from 64 +/- 1% to 67 +/- 1% (p less than 0.001) after doxorubicin. In addition, peak ejection rate (p less than 0.005) and peak filling rate (p less than 0.0005) increased significantly following short-term doxorubicin administration. There was no relationship between either the individual or cumulative dose of doxorubicin and the acute ejection fraction, peak ejection rate, or peak filling rate response. Our data suggest that doxorubicin acutely increases left ventricular systolic and diastolic function.

Homoharringtonine-induced hyperglycemia

Homoharringtonine (HHT) has been reported to induce hyperglycemia. This report describes a study conducted to characterize the effect of HHT on insulin production and action. Our data indicate that HHT-induced hyperglycemia results from the development of insulin resistance. A review of the literature suggests that patients receiving HHT continuous infusions of 5 mg/m2/d or greater and patients greater than 10 years of age may be at increased risk for the development of HHT-induced hyperglycemia. We recommend that patients with these risk factors, as well as diabetic patients and patients concurrently receiving asparaginase and/or prednisone, have their blood glucoses routinely monitored for hyperglycemia.

Breast cancer and aging

While many of the basic principles of breast cancer management are the same for younger and older women, a number of breast cancer issues particularly important for elderly women have not been resolved. Many of these management questions need answers based on data that are better than that currently available. At what age should the clinician consider cessation of screening mammography? For which very elderly patients might tamoxifen alone be adequate treatment for primary operable breast cancer? How can we develop better guidelines for the selection and administration of cytotoxic chemotherapy in an elderly population? What is the appropriate systemic adjuvant therapy, if any, for the patient over the age of 70? These and other questions may be answered through the development of clinical trials directed specifically at the elderly population.

The effect of preoperative apple juice on gastric contents, thirst, and hunger in children

The effect of 3 ml.kg-1 of apple juice given 2.6 +/- 0.4 hours preoperatively was investigated in 80 healthy children of ages five to ten years in this prospective, randomized, single blind study. The children who drank apple juice preoperatively had decreased gastric volume, thirst, and hunger (p less than 0.05). The gastric volume in the control group was 0.43 +/- 0.46 ml.kg-1 and in the patients who received apple juice the gastric volume was 0.24 +/- 0.31 ml.kg-1. The gastric pH was not significantly different, with the control group's gastric pH being 1.7 +/- 0.6 and the treated group's pH was 2.2 +/- 1.2. Further studies of the effects of different volumes and timing of preoperative clear fluids are indicated in paediatric patients.

Continuous infusion homoharringtonine (NSC 141633) in refractory acute nonlymphocytic leukemia. An ECOG pilot study

Single-agent homoharringtonine (HH) was evaluated as induction therapy in 20 patients with advanced acute nonlymphocytic leukemia (ANLL) in a pilot study of the Eastern Cooperative Oncology Group (ECOG). HH was given by continuous intravenous (i.v.) infusion at 3.5 mg/m2 on the first day and at 6.0 mg/m2/day on days 2-8. Fourteen men and six women with a median age of 43 years were treated. Sixteen patients had clearing of peripheral blasts, 10 patients achieved marrow hypoplasia, and 2 patients had progressive disease. No complete remission occurred. Drug-induced hypotension was the most significant toxicity, causing a delay in treatment in 8 patients. The median survival was 15 weeks (range 1-65 weeks) from the start of HH treatment. Despite a definite antileukemic effect, HH as a single agent cannot be recommended as a useful salvage regimen in patients with far advanced ANLL.

Peripheral B lymphocyte percentage as an indicator of subclinical progression of bovine leukemia virus infection

The relationship between percentage of B cells in peripheral blood and subclinical bovine leukemia virus infection was examined in a herd of 240 Holstein-Friesian cows. Absolute leukocyte count and absolute lymphocyte count were significantly positively correlated with B cell percentage in cows that were seropositive to bovine leukemia virus envelope glycoprotein, but these parameters were not correlated in seronegative cows. The B cell percentage was not affected by age. Cows that had persistent lymphocytosis and hematologically normal seropositive cows had greater mean B cell percentages (78 and 45%, respectively) than did seronegative herdmates (37%). To evaluate B cell percentage as a means of detecting subclinical progression of bovine leukemia virus infection, an index was developed based upon the distribution of B cell percentages in seronegative cows. When this index was compared with a standard hematological key (the European Community's Leukosis Key), which is based on absolute lymphocyte count and age, 29% of seropositive, hematologically normal cows had B cell percentages two standard deviations above the mean of their seronegative herdmates. The B cell percentage was thus shown to be more effective than absolute lymphocyte count for detecting subclinical progression of bovine leukemia virus infection in individual cows.

Provocation-neutralization: a two-part study. Part I. The intracutaneous provocative food test: a multi-center comparison study

This study investigated the clinical usefulness of the intracutaneous provocative-neutralization food test (IPFT). Thirty-seven patients were tested for five identical food allergies by eight physicians in different geographical locations. Throughout the study, comparison was made between the IPFT when interpreted by skin response (IPFT SK) and when interpreted by symptom provocation (IPFT PR). Double-blind IPFT results were compared with those of previously accomplished oral challenge food tests (OCFT). IPFT reliability was determined by a double-blind comparison of the initial IPFT, with two subsequent IPFTs performed 7 days apart. Correlation of the IPFT SK and IPFT PR with the OCFT provided validity coefficients of 0.78 and 0.61 respectively, both significant beyond the 0.01 level of confidence. Reliability of the IPFT SK and IPFT PR was shown to be 0.68 and 0.40, respectively. The IPFT SK was significant beyond the 0.01 level of confidence and the IPFT PR was significant beyond the 0.05 level of confidence.

Phase I clinical and pharmacokinetic study of trimetrexate using a daily x5 schedule

Trimetrexate (TMQ; NSC 352122) is a potent inhibitor of dihydrofolate reductase with good activity against murine i.p.-implanted B16 melanoma and colon 26 tumors. Preclinical antineoplastic activity, demonstrated schedule dependency, and data suggesting effectiveness against methotrexate-resistant cells prompted a Phase I clinical and pharmacokinetic study of trimetrexate using an i.v. daily x5 schedule. Forty-three good performance status patients were treated with 12 dose levels using daily doses varying from 0.5 to 15 mg/m2/d. Plasma and urine samples were obtained for pharmacokinetic analysis using a high-performance liquid chromatographic method. Myelosuppression was dose limiting and 15 mg/m2/d x5 was the maximum tolerated dose. White blood cell (WBC) and platelet toxicity were noted at doses of 1.6 mg/m2 and above. Median WBC and platelet nadirs occurred on approximately Days 11-12 with recovery by Days 15-18. Nonhematological toxicity included mucositis, nausea and vomiting, stomatitis, diarrhea, and rash. Evidence for antitumor activity was seen in seven patients. Trimetrexate elimination from plasma could be represented as either a bi- or triexponential process. Terminal elimination half-lives were in the range of 5-14 h in patients represented by a triexponential model. Approximately 10-20% of the dose administered was excreted in urine over a 24-h period. The recommended starting dose for patients in Phase II trials using the d x5 i.v. schedule is 8.0 mg/m2/d repeated every 21 days. Dose escalations may be possible depending on the extent of prior therapy and individual tolerance of the drug.