Comparison of renal function following anesthesia with low-flow sevoflurane and isoflurane

STUDY OBJECTIVE

To evaluate postoperative renal function after patients were administered sevoflurane under conditions designed to generate high concentrations of compound A.

STUDY DESIGN AND SETTING

A multicenter (11 sites), multinational, open-label, randomized, comparative study of perioperative renal function in patients who have received low-flow (< or = 1 L/min) sevoflurane or isoflurane.

PATIENTS

254 ASA physical status I, II and III patients requiring endotracheal intubation for elective surgery lasting more than 2 hours.

INTERVENTIONS

After induction, low-flow anesthesia was initiated at a flow rate < or = 1 L/min. Blood and urine samples were studied to assess postoperative renal function.

MEASUREMENTS AND MAIN RESULTS

Measurements of serum BUN and creatinine, and urine glucose, protein, pH, and specific gravity were used to assess renal function preoperatively and up to 3 days postoperatively. Serum inorganic fluoride ion concentration was measured at preinduction, emergence, and 2, 24 and 72 hours postoperatively. Compound A concentrations were measured at two sites for those patients receiving sevoflurane. Adverse experience data were analyzed. One hundred eighty-eight patients were considered evaluable (98 sevoflurane and 90 isoflurane). Peak serum fluoride concentrations were significantly higher after sevoflurane (40 +/- 16 microM) than after isoflurane (3 +/- 2 microM). Serum creatinine and BUN decreased in both groups postoperatively; glucosuria and proteinuria occurred in 15% to 25% of patients. There were no clinically significant differences in BUN, creatinine, glucosuria, and proteinuria between the low-flow sevoflurane and low-flow isoflurane patients.

CONCLUSIONS

There were no statistically significant differences in the renal effects of sevoflurane or isoflurane in surgical patients undergoing low-flow anesthesia for up to 8 hours. Low-flow sevoflurane anesthesia under clinical conditions expected to produce high levels of compound A appears as safe as low-flow isoflurane anesthesia.

An immunohistochemical study of the distribution of biotin in tissues of pigs and chickens

An optimised indirect peroxidase-anti-peroxidase immunohistochemical technique was used to detect endogenous biotin in frozen tissue sections from biotin-supplemented and biotin-depleted pigs and chickens. A monoclonal anti-biotin antibody was used as primary antibody in this technique. Immunoreactive biotin was detected in many tissues of both species including liver, kidney, pancreas, adipose tissue, adrenal gland, testis, brain, choroid plexus, cardiac and skeletal muscle, epithelium of the respiratory and digestive systems, skin and lymphoid tissues. The specificity of immunostaining for biotin was confirmed by the finding of reduced staining intensities in tissues of biotin-depleted animals compared to those of biotin-supplemented animals. The results of this study suggest that biotin has metabolic functions in a wider range of tissues than previously known. They also indicate that endogenous tissue biotin should be considered as a source of false-positive staining when immunohistochemical or histochemical techniques which use avidin or streptavidin reagents or anti-biotin antibodies as components of the detection system, are applied to tissue sections.

Histopathologic and ultrastructural alterations of white liver disease in sheep experimentally depleted of cobalt

Many cobalt-deficient sheep develop liver lesions known as ovine "white liver" disease, but the etiology of these changes is controversial. It has been suggested that cofactors are required for development of liver damage in cobalt-deficient sheep. In this study, one group of lambs (n = 5) was fed a diet low in cobalt (4.5 micrograms/kg) while a group of control lambs (n = 4) received the same diet after it had been supplemented with cobalt (1000 micrograms/kg). All cobalt-depleted lambs had reduced growth rate, anorexia, lacrimation, and alopecia, and they eventually became emaciated (mean body weight at end of study: 83% of initial body weight). Plasma concentrations of bilirubin and serum activity of glutamate-oxaloacetate transferase were elevated in these animals, while plasma concentrations of vitamin B12 were reduced (less than 220 pmol/L from day 42). Fatty degeneration of the liver associated with reduced concentrations of vitamin B12 (14.5 pmol/g) was seen in these animals at necropsy at 196 days. Microscopic liver lesions included accumulation of lipid droplets and lipofuscin particles in hepatocytes, dissociation and necrosis of hepatocytes, and sparse infiltration by neutrophils, macrophages, and lymphocytes. Ultrastructural hepatocytic alterations included swelling, condensation and proliferation of mitochondria, hypertrophy of smooth endoplasmic reticulum, vesiculation and loss of arrays of rough endoplasmic reticulum, and accumulation of lipid droplets and lipofuscin granules in cytoplasm of hepatocytes. No liver lesions were seen in control lambs. The results of this study indicate that cofactors are not a prerequisite to development of hepatic damage in cobalt-deficient sheep. Reduced activities of the vitamin B12-dependent enzymes, methylmalonyl CoA mutase and methionine synthase, and lipid peroxidation are of likely pathogenetic importance in the development of the lesions.

Growth of tumor-infiltrating lymphocytes from human solid cancers: summary of a 5-year experience

Between 1989 and 1993, 255 tumor biopsies representing 4 tumor histologies (melanoma, breast cancer, colon cancer and renal cell cancer) were received by the Surgery Branch of the National Cancer Institute. Tumor-infiltrating lymphocytes (TIL) were grown from single-cell suspensions of tumor biopsies over the course of 30-45 days. The TIL were grown in medium containing IL-2. To obtain numbers suitable for therapy (>10(11)), TIL were expanded using a large-scale system of cell culture and harvesting. While the largest number of biopsies was obtained from melanoma patients, TIL were successfully grown from 160 of 255 tumor biopsies representing all 4 histologies. Under the culture conditions employed, several characteristics of TIL expansion were observed. The cell surface phenotype of TIL which grew out from the tumor biopsies was generally a mix of CD3+/CD4+ or CD3+/CD8+ lymphocytes. Only TIL from melanoma biopsies were found to be consistently cytolytic and, in many cases, lysed autologous tumor cells preferentially. Interestingly, TIL derived from extra-nodal sites of metastatic melanoma biopsies (subcutaneous, lung, bowel; 36 of 67, 54%) were more likely to have these cytolytic characteristics than TIL derived from tumor-involved lymph node biopsies (7 of 39, 18%). The present study summarizes 5 years of laboratory effort and validates the technologies developed for the large-scale growth and harvesting of TIL. In addition, it summarizes the laboratory effort supporting previously published clinical reports on TIL from our group.

Melanoma tumor-infiltrating lymphocytes derived from four distinct anatomic sites obtained from a single patient: comparison of functional reactivity and melanoma antigen recognition

Tumor-infiltrating lymphocytes (TILs) were grown from four distinct anatomic sites from a patient with metastatic melanoma. The metastatic sites included a tumor-involved lymph node, a subcutaneous lesion obtained from the chest wall, a portion of bowel, and adrenal gland. TILs grown from each anatomic site over the course of 20 days in the presence of 6,000 IU/ml recombinant interleukin-2 exhibited comparable growth rates. Between days 30 and 45, the TILs were a mixture of CD3+ CD4+ and CD3+ CD8+ lymphocytes expressing the alpha beta form of the T-cell receptor. TILs derived from each anatomic site specifically lysed autologous tumor obtained from all four anatomic sites. In fine specificity analysis, the TILs exhibited human leukocyte antigen (HLA-A2)-restricted lysis of fresh tumor targets and cultured melanoma cell lines. Each TIL recognized a product of the MART-1 gene, and specifically, the monomer peptide MART-1(27-35). Thus lymphocytes reactive with the MART-1 melanoma antigen appeared to be widely distributed in diverse metastases in this patient. This information, along with previous data on the reactivity of multiple patients to this antigen, attests to its dominance in the immune reactivity of humans to melanoma.

Policy issues surrounding special care units

What is specialized care for Alzheimer's patients? Is it really specialized, or could that word simply be a marketing ploy? Home care agencies that care for patients with Alzheimer's disease will face these questions with their patients and undergo the same questions that the nursing home industry faces.

Vaccination of newborn pigs in the presence of low levels of pseudorabies colostral antibodies

To test the hypothesis that newborn pigs with pseudorabies virus (PRV) colostral antibodies might be actively immunized with a PRV glycoprotein gIII-deleted vaccine (Omnimark-PRV), 23 piglets were obtained from four sows that had been immunized 4 weeks and 2 weeks before farrowing with this vaccine. Thirteen piglets were immunized with Omnimark-PRV when they were less than 3 days old and ten piglets served as non-vaccinated controls. Piglets were weaned at 28 days of age and challenged with virulent PRV (Shope) when they were 49 days old, at which time the vaccinated and control pigs were seronegative for PRV virus neutralizing (VN) and gIII antibodies, and all control pigs and ten vaccinees were seronegative for PRV antibodies by the latex agglutination test (LAT). Two vaccinees were LAT(+) and one was LAT(+/-). Central nervous system signs and/or respiratory disease signs were observed in six of ten control pigs with the death of one control, while two of 13 vaccinees showed only very mild and transient clinical disease signs and there were no fatalities. Non-vaccinees lost weight until postchallenge day (PCD) 6 and did not regain prechallenge weight until PCD 8. All vaccinees gained weight after challenge and at PCD 11 had mean weight gains nearly twice that of the controls. On PCD 11, the geometric mean titre for VN antibodies of non-vaccinees was 9.3, while that of vaccinees was 49.0, indicating that the vaccinated group had been immunologically primed.

Circumvention of maternal antibody interference by immunization of newborn pigs with glycoprotein gIII-deleted marker vaccine

Maternal antibodies interfere with the immunization of swine by modified live-virus pseudorabies virus (PRV) vaccines. To test the hypothesis that a PRV vaccine attenuated by deletions in the thymidine kinase (TK) and gIII genes might reduce interference by maternal antibodies, pigs with moderate to low levels of colostral PRV antibodies were immunized with the TK- gIII-OMNIMARK-PRV vaccine. Vaccinates and non-vaccinates were challenged intranasally with virulent PRV at 7 weeks of age. In support of the hypothesis, it was found that central nervous system (CNS) and/or respiratory disease developed in six out of 10 controls with a fatal outcome in one, while two out of 13 vaccinates showed only very mild and transient CNS or respiratory disease signs with no fatalities. All vaccinates gained weight while non-vaccinates initally lost weight. At post-challenge day (PCD) 11, vaccinates showed 4.5 lb/pig greater weight gain than non-vaccinates. Virus neutralization (VN) analyses before and after challenge showed that vaccinates had been primed immunologically. In another experiment, newborn pigs from a pseudorabies disease-quarantined herd with high VN antibody titres were vaccinated, respectively, with the gIII-TK-OMNIMARK-PRV vaccine, a TK-gI-gX-vaccine, or no vaccine and challenged with virulent PRV at 14 weeks of age when VN titres were < 1:2. By PCD 9, the TK-gIII-group had outgained the TK-gI-gX- and the control groups, respectively, by 6.0 and 3.2 lb per pig.

Histological, histochemical and ultrastructural features of hyaline inclusions in hepatocytes of striped dolphins (Stenella coeruleoalba)

Many striped dolphins (Stenella coeruleoalba) which died in the recent morbillivirus epizootic in the Mediterranean Sea had hyaline inclusions in hepatocytes. We investigated the histological, histochemical and ultrastructural features of these inclusions in two affected dolphins. Histochemical tests indicated that they contained glycoprotein but not lipid. Ultrastructurally, they consisted of granular, moderately electron-dense material, bounded by a membrane. A central or eccentric core of highly electron-dense material was usually apparent. The inclusions were probably of lysosomal origin.

Coronary angioplasty with gradual versus rapid balloon inflation: initial results and complications

Although a variety of coronary angioplasty balloon inflation protocols are employed, prior studies have not evaluated the relation of rate of inflation to the type and extent of arterial damage produced by angioplasty. We randomized 103 patients to either a gradual (gradual, incremental increase to peak inflation pressure) or rapid inflation protocol (rapid increase to peak inflation pressure). Fifty-one patients with 72 lesions underwent gradual and 52 patients with 73 lesions received rapid inflation protocols. There were no significant group differences with regard to age, sex, artery dilated, number of diseased vessels, presence of unstable angina and lesion morphological characteristics except for more lesions located on a bend in the gradual inflation group (p < 0.02). Although there was a tendency towards a higher success rate in patients with gradual inflation, the complete success rates were high in both groups (100% vs. 93%, p < 0.08). The dissection rate was higher in patients with rapid inflation (43/73 [59%] vs. 26/72 [36%], p < 0.01). The collective complication rate was higher in patients with rapid inflation (19% vs. 6%, p < 0.03). No deaths occurred in either group. Thus a gradual compared to rapid coronary angioplasty balloon inflation protocol reduces the frequency of dissection despite similar inflation pressure and balloon/vessel diameter ratio. Gradual inflations may reduce the frequency of procedure-related complications.

Health care for all: long-term care, the missing piece. A roundtable discussion: Part 3

Long-term care has been described as the "missing piece" in many healthcare reform proposals. Yet the cost of nursing home care often exceeds that of acute care, especially for the elderly with Alzheimer's disease. In this final installment of a three-part roundtable discussion, panelists discuss the options for providing long-term care, such as social insurance, a single-payer system, play or pay, or private insurance models. Alternatives to nursing home care, such as community service centers and home care, are discussed. The panelists conclude with an examination of how these proposed reforms might affect the practices of physicians and the U.S. economy.

Health care for all: comparing proposals for reform. A roundtable discussion: Part 2

Part 1 of this roundtable discussion [Geriatrics 1992; 47(Sept):34-48] examined the flaws in our current healthcare system and factors that are interfering with our nation's ability to achieve reforms. This month, the panelists discuss the benefits and drawbacks of the major healthcare reform proposals, including managed care, single-payer systems, and so-called "play or pay." The practical aspects of any redistribution of healthcare resources are considered as each panelist outlines a favored approach. The influence of special interests, such as the insurance industry, is also discussed.

Age-related changes in binding to excitatory amino acid uptake sites in human cerebellum

In vitro autoradiography and test-tube assay of the sodium-dependent binding of D-[3H]aspartate were used to localize and quantify the uptake site for the excitatory amino acid neurotransmitters glutamate and aspartate in the cerebellar cortex of human cerebellar hemispheres. Autoradiograms revealed a pronounced heterogeneity in the distribution of D-[3H]aspartate binding in cortex from adult brains, with the highest binding density corresponding to the Purkinje cell layer, high binding in molecular layer and low binding in granule cell layer. In contrast, cerebellar cortex from infants at term (40 weeks gestation) had only low binding of the ligand in both the molecular and the Purkinje cell layers. Both methods employed for measuring D-[3H]aspartate binding showed that the number of binding sites in Purkinje and molecular layers increased rapidly from term to 20 weeks postnatal age and achieved levels higher than those found in adult cerebellum. It is concluded that a substantial increase in the numbers of glutamate/aspartate uptake sites takes place in the human cerebellum during the early postnatal period. It is deduced that the excess uptake sites are eliminated as the cerebellum matures.

Age-related changes in binding to excitatory amino acid uptake site in temporal cortex of human brain

The binding of D-[3H]aspartate to the specific uptake site for the excitatory amino acids glutamate and aspartate was measured in homogenates of temporal lobe cortex taken at postmortem from 76 human infant and adult brains. Binding levels were very low in brains of preterm and term infants but increased rapidly during the first 20 postnatal weeks to reach levels which exceeded those in adult brains. Linear regression analysis which compared the amount of D-[3H]aspartate binding with the age of the infant, showed a positive correlation up to 25 postnatal weeks. Saturation analysis showed that the maximum number of D-[3H]aspartate binding sites (Bmax) in temporal cortex from infants aged 20 postnatal weeks was 3 times greater than the number of sites in adult brain. The findings show that the number of excitatory amino acid uptake sites, which may be associated in part with presynaptic terminals, increase in number rapidly after birth. Furthermore, the data may indicate that a slow regression of excitatory amino acid terminals occurs during the later stages of brain development.

Alzheimer's disease. Getting on the federal agenda

Eleven years ago, a handful of family caregivers started a grassroots movement that has raised the nation's awareness of Alzheimer's disease and captured the attention of government policymakers.

Ultrastructural features of alveolar lesions in induced respiratory syncytial virus pneumonia of calves

Ultrastructural changes occurred in alveolar epithelium in the acute and repair stages of induced respiratory syncytial virus pneumonia induced in eight calves (calf Nos. 1-7, 3 to 6 days old and calf No. 8, 2 weeks old), using a bovine strain of respiratory syncytial virus. Five of the calves were Friesians, three were Hereford x Friesians, and all were male. Tissues from three mock-infected control calves (two Friesian, one Hereford x Friesian) were also examined. Evidence of respiratory syncytial virus infection was observed in both type I and type II pneumocytes from day 4 to day 8 after infection. Infection of type I pneumocytes frequently resulted in necrosis. The response of type II pneumocytes to respiratory syncytial virus infection varied and included hypertrophy, hyperplasia, and syncytial formation. In some infected type II pneumocytes, there were numerous irregular projections of the cell surface, associated with viral budding. Hypertrophy and hyperplasia of type II pneumocytes, epithelial syncytium formation, and irregular cytoplasmic projections from epithelial cells caused considerable thickening of respiratory membrane and occlusion of alveolar lumina. Neutrophils were frequently observed in close association with virus-infected epithelial cells, but evidence of respiratory syncytial virus infection and replication was not observed in alveolar macrophages or neutrophils. Proliferation of type II pneumocytes appeared to play a major role in maintaining the integrity of the alveolar epithelium during the acute stage of the experimental pneumonia. Increased numbers of type II pneumocytes were present on alveolar walls, particularly from 4 to 8 days after infection, and some alveoli were lined entirely by this cell type. In some areas, however, squamous epithelial cells were also involved in covering exposed alveolar basement membrane.

Ultrastructural features of lesions in bronchiolar epithelium in induced respiratory syncytial virus pneumonia of calves

Ultrastructural changes were observed in bronchioles in acute and repair stages of respiratory syncytial virus pneumonia induced in eight young calves (calf Nos. 1-8) using a bovine strain of respiratory syncytial virus. Five of the calves were Friesians and three were Hereford x Friesians and all were male. Tissues from three mock-infected control calves (two Friesian, one Hereford x Friesian) were also examined. Calves were from 3 to 6 days old at the time of first inoculation, with the exception of calf No. 8, which was 2 weeks old. In the acute stage of the induced pneumonia, evidence of respiratory syncytial virus replication and release was demonstrable in both ciliated and non-ciliated bronchiolar epithelial cells, with the virus-releasing process most obvious at 4 and 5 days after infection. Respiratory syncytial virus infection of bronchiolar epithelium was associated with various changes, including hypertrophy, hyperplasia, and formation of syncytia. Necrosis of epithelial cell structures usually appeared to be preceded by their desquamation from bronchiolar walls. Respiratory syncytial virus infection resulted in considerable damage to the bronchiolar ciliary apparatus. Such damage was seen as early as 1 day post-infection and was still obvious at 10 days post-infection. Neutrophils were closely associated with respiratory syncytial virus infected epithelial cells and evidence of neutrophil fusion with infected epithelial cells was seen. These observations suggest that neutrophils may be involved in killing respiratory syncytial virus infected cells and that neutrophils might play an important role in early antiviral defense against respiratory syncytial virus at a time when antibody levels are low and other cellular defenses are not fully in play. Bronchiolar repair was evident from 6 days after infection and was well advanced at 10 and 13 days after infection.

Safety and efficacy of a thymidine kinase negative equine herpesvirus-1 vaccine in young horses

A drug induced equine herpesvirus-1 (EHV-1) mutant lacking thymidine kinase inducing activity was developed and evaluated as a vaccine. The safety and effectiveness of the vaccine to protect against experimentally induced EHV-1 respiratory disease were evaluated in weanling horses free of EHV-1 neutralizing antibody. The vaccine was safe when administered either intramuscularly or intravenously, and EHV-1 was not shed intranasally during the 12 days following administration. Intranasal challenge with virulent EHV-1 was used to evaluate vaccine efficacy. Following challenge, there was a significantly (p less than 0.05) greater increase in peak body temperatures and duration of nasal virus shedding in the nonvaccinates, and a significant (p less than 0.05) increase in serum neutralizing antibody titers in the vaccinates.