Molecular phylogenetic evidence for an extracellular Cu Zn superoxide dismutase gene in insects.

Representatives of three ancient gene families of the antioxidant enzyme superoxide dismutase (SOD) can be found in most metazoans. In mammals and Caenorhabditis elegans, there is at least one gene each of the cytoplasmic, mitochondrial and extracellular lineages of SOD genes. The cytoplasmic SOD was one of the first enzymes to be implicated in ageing due to its protection against damaging oxygen free radicals. In contrast to other metazoans, insects were thought to lack a gene for the extracellular SOD. We have cloned and sequenced an SOD mRNA in the ant Lasius niger that appears to belong to this extracellular family. Subsequent searches and analyses of SOD gene sequences in insect databases revealed that insects do indeed express all three SOD genes including the extracellular form. We conclude that insects as well as other metazoans appear to have the full repertoire of the three families of SOD.

Using microsatellite and MHC variation to identify species, ESUs, and MUs in the endangered Sonoran topminnow.

Highly variable loci can provide insight into the recognition of species, evolutionarily significant units (ESUs) and management units (MUs). In general, the ESU and MU categories are thought to be reflective of adaptive differences between them. Here we examine this premise by presenting a comprehensive examination of genetic variation for both microsatellite loci and a major histocompatibility complex (MHC) locus, thought to be of adaptive significance, in the endangered Sonoran topminnow. The extent of variation for the microsatellite loci and the MHC gene within the 13 populations of the Gila topminnow is highly correlated, suggesting that nonselective factors have played an important role in influencing variation within and between populations for the MHC locus. Therefore, using all of these loci, we found that the eight natural populations of the Gila topminnow fell into two different ESUs, one of which had four different MUs. The source of the Boyce Thompson sample, a population that was used extensively for restocking, appeared to be Monkey Spring. The source of the Watson Wash population also appeared to be Monkey Spring (or Boyce Thompson). The newly colonized Santa Cruz River population, which had the most genetic variation of any Gila topminnow population, appeared to descend primarily from Sonoita Creek populations. The Yaqui topminnow, presently considered another subspecies of the Sonoran topminnow, was very distinct for both microsatellite (only two of 25 alleles found in the Yaqui were in any of the Gila topminnow samples) and MHC alleles (nonoverlapping sets of alleles for the two groups). As a result, it appeared that the taxonomic status of the two subspecies should be re-evaluated and that full species status for Gila and Yaqui topminnows was appropriate. There was evidence for the importance of long-term selection at the MHC locus in the higher rate of nonsynonymous than synonymous substitution. In addition, there appeared to have been a duplication of the MHC locus that was present in most of the fish in six of the natural populations of the Gila topminnow.

Optimal use of spironolactone for treatment of heart failure.

Spironolactone has recently been shown to have a favorable impact on the prognosis and functional status of patients with left ventricular systolic dysfunction and severe symptoms who are receiving standard therapy. However, participants in clinical studies of spironolactone represent a selected group. Clinicians managing a less selected group must be mindful of selection criteria and appropriate methods to monitor patients who are initiated on these medications. In this review, two case studies are described that demonstrate the importance of careful selection of candidates for spironolactone, the need for close laboratory and symptom monitoring, and the need for patients' active participation in reporting changes in their clinical status. (c)2001 CHF, Inc.

Early feeding and the incidence of gastrointestinal symptoms after major gynecologic surgery.

OBJECTIVE: To compare early feeding with traditional postoperative dietary management for development of postoperative gastrointestinal symptoms, including ileus after major gynecologic surgery for benign conditions. METHODS: Women who had major gynecologic surgery for benign conditions were randomly allocated to early feeding of low residue diets 6 hours postoperatively or traditional dietary management of clear liquids with normal bowel sounds, and regular diet with passage of flatus. Demographic and perioperative data were collected, and patients answered questionnaires on their perception of bowel function and pain using the McGill Pain Scale. Power analysis found that 130 women were needed to find a twofold greater incidence of ileus in the early feeding group with 80% power and alpha =.05. RESULTS: Complete data were available for 139 women, 67 allocated to the early feeding group and 72 to the late feeding group. The incidence of postoperative ileus for the study population was 4.4% and did not differ between groups (early 3% versus late 5. 8%, P =.68). There were no differences in patient demographics, surgical procedures, anesthesia used, and intraoperative complications between groups. With the exception of more complaints of nausea in the late feeding group (23% versus 13%, P =.04), there were no differences in other postoperative variables, including other perioperative complications, pain medicine requirements, fluid and caloric intake, median pain scores, and gastrointestinal function. The low incidence of perioperative complications made the power to detect differences between groups low. CONCLUSION: Low residue diet 6 hours after major gynecologic surgery for benign indications was not associated with increased postoperative gastrointestinal complaints, including ileus.

Potentiation of oxygen-induced lung injury in rats by the mechanism-based cytochrome P-450 inhibitor, 1-aminobenzotriazole.

In this investigation, we tested the hypothesis that the cytochrome P-450 (CYP) inhibitor 1-aminobenzotriazole (ABT) alters the susceptibility of rats to hyperoxic lung injury. Male Sprague-Dawley rats were treated i.p. with ABT (66 mg/kg), i.v. with N-benzyl-1-aminobenzotriazole (1 micromol/kg), or the respective vehicles, followed by exposure to >95% oxygen for 24, 48, or 60 h. Pleural effusion volumes were measured as estimates of hyperoxic lung injury, and lung microsomal ethoxyresorufin O-deethylation (EROD) (CYP1A1) activities and CYP1A1 apoprotein levels were determined by Western blotting. ABT-pretreated animals exposed to hyperoxia died between 48 and 60 h, whereas no deaths were observed with up to 60 h of hyperoxia in vehicle-treated animals. In addition, three of four ABT-treated rats exposed to hyperoxia for 48 h showed marked pleural effusions. Exposure of vehicle-treated rats to hyperoxia led to 6.3-fold greater lung EROD activities and greater CYP1A1 apoprotein levels than in air-breathing controls after 48 h, but both declined to control levels by 60 h. Liver CYP1A1/1A2 enzymes displayed responses to hyperoxia and ABT similar to the effects on lung CYP1A1. N-Benzyl-1-aminobenzotriazole markedly inhibited lung microsomal pentoxyresorufin O-depentylation (principally CYP2B1) activities in air-breathing and hyperoxic animals but did not affect lung EROD or liver CYP activities. In conclusion, the results suggest that induction of CYP1A enzymes may serve as an adaptive response to hyperoxia, and that CYP2B1, the major pulmonary CYP isoform, does not contribute significantly to hyperoxic lung injury.

Major histocompatibility complex (MHC) variation in the endangered Mexican wolf and related canids.

We have examined in Mexican wolves and related canids the amount of genetic variation for a class II gene in the major histocompatibility complex (MHC), thought to be part of the most important genetic basis for pathogen resistance in vertebrates. In Mexican wolves, descended from only seven founders over three lineages, there were five different alleles. These were in three phylogenetic groups, only one of which was shared between lineages. Using single stand conformation polymorphism (SSCP), we found that in samples of animals from the two polymorphic lineages, the observed heterozygosity was 0.74 and the genotypes were not different statistically from Hardy-Weinberg proportions. The Ghost Ranch lineage of Mexican wolves was monomorphic for the locus, consistent with the lower level of variation found previously for microsatellite loci and predicted from pedigree analysis. Samples of grey wolves, red wolves, and coyotes had 16 additional alleles. One Mexican wolf allele was also found in grey wolves and another allele was shared between grey and red wolves. Most of the nucleotide variation resulted in amino acid variation and there were five different amino acids found at two different positions. Only two of the 21 variable amino acid positions had solely synonymous nucleotide variation. The average heterozygosity for eight individual amino acid positions in the Mexican wolves was greater than 0.4. The estimated rate of nonsynonymous substitution was 2.5 times higher than that for synonymous substitution for the putative antigen binding site positions, indicative of positive selection acting on these positions. Examination of the known dog sequences for this locus showed that one of the Mexican wolf alleles was found in dogs and that the allele found in both grey and red wolves is also found in dogs.

Major histocompatibility complex variation in the Arabian oryx.

In the 1960s, the Arabian oryx was one of the most endangered species in the world, extinct in the wild and surviving in only a few captive herds. The present day population of over 2000 descends from a small number of founders and may have restricted genetic variation for important adaptive genes. We have examined the amount of genetic variation for a class II gene in the major histocompatibility complex thought to be the most important genetic basis for pathogen resistance in vertebrates. We found three very divergent alleles, which on average, differed by 24 nucleotides and 15 amino acids in the 236-bp fragment we examined. Using single-strand conformation polymorphism, we found that in a sample of 57 animals, the alleles were in Hardy-Weinberg proportions, although one allele was found only in four heterozygous individuals. The average heterozygosity for the 22 amino acid positions involved in antigen binding was 0.165, three times as high as that for the 56 amino acids not involved with antigen binding. Because the three alleles have such divergent sequences, it is likely that they may recognize peptides from quite different pathogens. As a result, maintenance of these variants should be considered as a goal in the captive breeding program of the Arabian oryx.

Major histocompatibility complex variation in the endangered Przewalski's horse.

The major histocompatibility complex (MHC) is a fundamental part of the vertebrate immune system, and the high variability in many MHC genes is thought to play an essential role in recognition of parasites. The Przewalski's horse is extinct in the wild and all the living individuals descend from 13 founders, most of whom were captured around the turn of the century. One of the primary genetic concerns in endangered species is whether they have ample adaptive variation to respond to novel selective factors. In examining 14 Przewalski's horses that are broadly representative of the living animals, we found six different class II DRB major histocompatibility sequences. The sequences showed extensive nonsynonymous variation, concentrated in the putative antigen-binding sites, and little synonymous variation. Individuals had from two to four sequences as determined by single-stranded conformation polymorphism (SSCP) analysis. On the basis of the SSCP data, phylogenetic analysis of the nucleotide sequences, and segregation in a family group, we conclude that four of these sequences are from one gene (although one sequence codes for a nonfunctional allele because it contains a stop codon) and two other sequences are from another gene. The position of the stop codon is at the same amino-acid position as in a closely related sequence from the domestic horse. Because other organisms have extensive variation at homologous loci, the Przewalski's horse may have quite low variation in this important adaptive region.

Major histocompatibility complex differentiation in Sacramento River chinook salmon.

The chinook salmon of the Sacramento River, California, have been reduced to a fraction of their former abundance because of human impact and use of the river system. Here we examine the genetic variation at a major histocompatibility complex class II exon in the four Sacramento chinook salmon runs. Examination of the alleles found in these and other chinook salmon revealed nucleotide patterns consistent with selection for amino acid replacement at the putative antigen-binding sites. We found a significant amount of variation in each of the runs, including the federally endangered winter run. All of the samples were in Hardy-Weinberg proportions. A significant amount of genetic differentiation between runs was revealed by several measures of differentiation. Winter run was the most genetically divergent, while the spring, late-fall, and fall runs were less differentiated.

Genotypic differences between C57BL/6 and A inbred mice in anxiolytic and sedative actions of diazepam.

The role of genotype in susceptibility to the behavioral actions of benzodiazepines is not well characterized. To develop a model for such studies, we have characterized the anxiolytic and sedative activities of diazepam in C57BL/6J and A/J inbred mice. C57BL/6J mice were more responsive than A/J mice to diazepam-induced anxiolytic-like activity in the mirrored chamber aversion assay and the elevated plus-maze assay. Basal activity of the two strains did not differ in either assay. In contrast, the two strains were equally responsive to the anxiolytic effects of the 5-HT1A receptor partial agonist, buspirone. C57BL/6J mice were also more susceptible to the sedative effects of diazepam than were A/J mice. Flumazenil blocked the effects of diazepam in these behavioral assays. Measurement of diazepam and nordiazepam in blood and brain suggested that the response differences are of a pharmacodynamic rather than a pharmacokinetic nature. Taken together, these findings indicate that C57BL/6J and A/J mice provide a valuable tool for behavioral genetic studies of the mechanisms underlying the pharmacological actions of benzodiazepines.

Sudden death due to tricuspid valve myxoma with massive pulmonary embolism in a 15-month old male.

Myxomas of the tricuspid valve are extremely rare, with only 13 cases reported in the world literature. We report the case of a 15-month old male with tricuspid valve myxoma and massive myxomatous pulmonary emboli discovered at autopsy.

Geographic variations in eosinophil concentration in normal colonic mucosa.

We reviewed 256 mucosal biopsy specimens from the descending and sigmoid colon obtained from surgical pathology departments in several areas of the United States. Only specimens of normal colonic mucosa were included, i.e., no specimens with acute or chronic colitis or adenomatous change, or in which eosinophils invaded the crypts or muscularis mucosae. The mean number of eosinophils per intercryptal space was highest in the southern United States, and there was a 35-fold difference between the mean eosinophil concentrations of patients in New Orleans and Boston. The reason for geographic variation is unknown, but it might be related to allergens in the environment or diet. Normal variations in mucosal eosinophil concentrations should be measured within a specific region before evaluating colonic biopsy specimens for eosinophilia.

A comprehensive management system for heart failure improves clinical outcomes and reduces medical resource utilization.

The effectiveness of heart failure management in clinical practice is limited by physicians' suboptimal utilization of effective medications, patients' poor adherence to dietary sodium limitation and optimal drug therapy, and the lack of systematic monitoring of patients after hospitalization. The present study evaluated the feasibility and safety of MULTIFIT, a physician-supervised, nurse-mediated, home-based system for heart failure management that implements consensus guidelines for pharmacologic and dietary therapy using a nurse manager to enhance dietary and pharmacologic adherence and to monitor clinical status by frequent telephone contact. Fifty-one patients with the clinical diagnosis of heart failure were followed for 138 +/- 44 days. Daily dietary sodium intake fell by 38%, from 3,393 to 2,088 mg (p = 0.0001); average daily medication doses increased significantly (lisinopril: 17 to 23 mg, p <0.001; hydralazine: 140 to 252 mg, p = 0.01). Functional status and exercise capacity improved significantly (p = 0.01). Compared with the 6 months before enrollment and normalized for variable follow-up, the frequency of general medical and cardiology visits declined by 23% and 31%, respectively (both p <0.03); emergency room visits for heart failure and for all causes declined 67% and 53%, respectively (both p <0.001). Hospitalization rates for heart failure and for all causes declined 87% and 74%, respectively (p = 0.001), compared with the year before enrollment. The MULTIFIT system enhanced the effectiveness of pharmacologic and dietary therapy for heart failure in clinical practice, improving clinical outcomes and reducing medical resource utilization.

Aspergillosis of the sphenoid sinus: presentation as a pituitary mass and postoperative gallium-67 imaging.

Invasive aspergillosis of the paranasal sinuses is an uncommon, but well-recognized, form of fungal infection. We describe an elderly female patient with invasive aspergillosis of the sphenoid sinus and associated osteomyelitis of the skull base, with clinical presentation as a pituitary mass. Postoperative gallium scan showed intense uptake in the sphenoid sinus, which resolved after treatment with amphotericin-B. This case demonstrates some of the pathologic and clinical features of invasive aspergillosis and suggests a potential role for gallium-67 imagining in monitoring clinical response to therapy.

Soft tissue oncocytoma.

We describe a case of a novel soft tissue neoplasm, composed of a monotonous population of cells. Their cytoplasm was parked with mitochondria, and had no immunohistochemical or ultrastructural evidence of differentiation. The neoplasm, located within the thigh of a 50-year old man, was well-circumscribed but unencapsulated. The patient was clinically free of neoplasm at 1 year follow-up, after complete local excision. We propose the term "soft tissue oncocytoma" for this lesion, because of the similarity of this neoplasm to oncocytomas of other reported sites.

Fatal post-cesarean endometritis: report of two Alabama cases.

Postpartum endometritis remains a major cause of morbidity in the puerperium with a fatal outcome on occasion. We present two cases of fatal, post-cesarean endometritis which occurred within a fifteen month period in Alabama. We discuss the features of endometritis including pathophysiology, causative organisms, risk factors and complications.

Acute isopropanol ingestion: pharmacokinetic parameters in the infant.

We describe a case of isopropanol intoxication in a 2-month-old infant. The source of isopropanol and both the route and time of ingestion could be clearly identified. Serial measurements of isopropanol and acetone provided data for calculating their respective elimination half-lives. Isopropanol (half-life = 5.8 hr) clearance was similar to values reported for adults; acetone (half-life = 10.8 hr) was eliminated twice as rapidly as in adults.

Delayed ethanol analysis of breath specimens: long-term field experience with commercial silica gel tubes and breathalyzer collection.

Delayed ethanol analysis was performed on breath specimens collected with commercial silica gel tubes using multiple Breathalyzer instruments. Eleven hundred and nine results were obtained from an ethanol testing program over a five-year period. Only 2.5% of the specimens had apparent collection errors. For the valid specimens, the most frequent result was 0.11 g/210 L and the mean result was 0.14 g/210 L. For 642 specimens, delayed results were compared with direct results. Direct results were greater than delayed results for 55%, less than for 27%, and equal to for 18% of the pairs. When fixed tolerance limits of +/- 0.03 were used, 81% of the direct results were confirmed. The confirmation percentage was best in the critical range of direct results, 0.05 to 0.15 g/210 L. The collection tubes showed no substantial variability in retaining ethanol during storage and releasing ethanol for analysis.