Variation in hsp gene expression and Hsp polymorphism: do they contribute to differential disease susceptibility and stress tolerance?

Auditory brainstem responses (ABR) and distortion product otoacoustic emissions (DPOAE) have been applied to the evaluation of peripheral auditory function. To date, no comparison of their relative sensitivities to aminoglycoside toxicity has been reported. The purpose of this study was to compare click evoked ABR testing and 2f1-f2 DPOAEs as detectors of cochlear damage induced by gentamicin treatment in guinea-pigs. ABR thresholds to click stimuli were recorded. DPOAE amplitude input/output functions were recorded using three different primary tone level conditions. In one condition, L1 was changed relative to a fixed L2. In the next condition, L2 was changed relative to a fixed L1. In the third condition, L1 and L2 were both changed while maintaining a consistent L1-L2 difference. Baseline L1-L2 differences were determined by adjusting L2 to produce the maximum DPOAE amplitude in each ear of each subject. Guinea-pigs were treated for a four week period with intramuscular injections of gentamicin. ABRs and DPOAEs were monitored and compared to baseline recordings or untreated control groups. DPOAE testing detected cochlear damage earlier than ABR testing. Changes in DPOAE input/output functions were noted after two weeks of treatment while changes in ABR threshold were not identified until after three weeks of treatment. The sensitivity of the DPOAE testing was related to the stimulus conditions utilized. L1-L2 differences were determined in the control group and for the initial test session by fixing L1 at 75 dB SPL and lowering L2 until the maximum DPOAE amplitude was obtained for each ear. All subsequent testing was begun using the optimal L1-L2 difference for each ear. The stimulus condition in which only L1 was changed and L2 was fixed resulted in the least sensitive DPOAE indicator of cochlear damage. The condition in which both L1 and L2 were changed, but the L1-L2 difference remained constant, resulted in the most sensitive indicator of damage. The onset and degree of cochlear damage secondary to gentamicin treatment was subject dependent. This study demonstrates that 2f1-f2 DPOAE testing is preferable to click evoked ABR testing for early detection of gentamicin toxicity of the cochlea. It also indicates that DPOAE stimulus parameters must be considered when developing test protocols. Specifically, recording the DPOAE amplitude input/output function while maintaining an effective L1-L2 difference is preferable to changing either L1 or L2 individually.     

The genetic susceptibility to Graves' disease

Graves' disease (GD) develops as a result of a complex interaction between genetic susceptibility genes and likely environmental factors. Most epidemiological data support an important genetic contribution to the development of GD. The concordance rate of GD in monozygotic twins is 30-60% and in dizygotic twins 3-9%, and thyroid autoantibodies have been reported in up to 50% of the siblings of patients with GD. For many years now, HLA studies have consistently shown an increased frequency of HLA-DR3 in Caucasian patients with GD; but with only a risk ratio of 3-5. However, recent advances in human genome mapping techniques have enabled the study of many other candidate genes. Of these additional, non-HLA genes, only CTLA-4 has been consistently found to be associated with GD. Using a linkage based approach which only detects highly significant susceptibility genes we have recently reported preliminary results which demonstrated that a marker located approximately 25 cM from the TSH receptor gene on chromosome 14q31 is linked to GD and in the same vicinity as the IDDM-11 locus. Such results, if confirmed, may signal the presence of a gene family related to endocrine autoimmunity on chromosome 14q31.     

Variation in electrophoretic karyotype and antifungal susceptibility of clinical isolates of Cryptococcus neoformans at a university-affiliated teaching hospital from 1987 to 1994

Ninety-eight isolates of Cryptococcus neoformans were collected from 30 patients at the University of Iowa Hospitals and Clinics from December 1987 through December 1994. The susceptibility of each isolate was determined against fluconazole, itraconazole, amphotericin B, and flucytosine. Of the 98 isolates, 53 were recovered from blood, 19 were recovered from cerebrospinal fluid (CSF), and 26 were recovered from other sources. Although the strains were isolated from the same institution, DNA typing by electrophoretic karyotype (EK) revealed wide genetic variation. Overall, 23 different EK profiles were identified by computer-aided analysis. An isolate exhibiting a single EK was isolated from 24 of 30 patients (80%), whereas multiple strains with unique EKs were isolated from 6 of 30 (20%) patients. Of the six patients who had multiple strains recovered, only one individual had two strains isolated from unique body sites, one strain from the blood and the other from the CSF. Six strains were isolated from multiple patients. Nine patients had multiple sequential isolates recovered over periods of time ranging from 3 days to 4 months. EK analysis revealed persistence of the same genotype in six of the cases. Three patients, however, appeared to have an isolate with a second distinct EK emerge during therapy. Of the patients with sequential positive cultures, an increase in the MICs for test agents was observed in only one case. C. neoformans isolates were collected over a period of 7 years, during which time MICs at our institution remained stable.     

Genetic susceptibility to visceral obesity and related clinical implications

This paper reviews evidence supporting the notion that genetic factors may have an influence on the determination of body fat distribution, particularly emphasizing the genetic susceptibility of visceral adipose tissue (AT) accumulation. The potential contribution of genetic susceptibility to the development of metabolic alterations in visceral obese individuals will also be reviewed. The contribution of genetic factors to the variation in body fat distribution is supported by studies in which racial differences in body fat distribution were reported. These ethnic differences suggest that body fat distribution may be influenced by some components of the genetic background which are shared among individuals of a given race. Furthermore, the familial aggregation and the resemblance between monozygotic twins that have been observed for anthropometric measurements of body fat distribution and for visceral AT accumulation measured by computed tomography, also suggest that genetic factors are involved in the determination of body fat distribution. Genetic susceptibility may also influence the relationship between visceral AT accumulation and the development of metabolic alterations. In this regard, it has been reported that the polymorphism of some genes (for example, the apolipoprotein (apo) E, apo B100 and lipoprotein lipase genes) is altering the relationship between visceral obesity and plasma lipoprotein-lipid levels. In conclusion, results presented in this paper suggest that genetic factors seem to have a significant influence on the propensity to accumulate AT in the visceral depot and that genetic factors also seem to affect the associations commonly reported between visceral obesity and the development of metabolic alterations.     

Bovine clinical mastitis due to coagulase-negative staphylococci and their susceptibility to antimicrobials

A total of 168 coagulase-negative staphylococci (CNS) strains were isolated from milk samples taken from cows with clinical mastitis. The samples were collected between January 1990 and August 1992 from cows in the veterinary surveillance area of the Ambulatory Clinic, College of Veterinary Medicine, Hautj?rvi, Finland. In 100 cases the effect of antibiotic treatment was evaluated 3-4 weeks after initial sampling. Clinical symptoms of the animals were recorded, and the inflammatory status of their udders was evaluated using the CMT test and assessing milk NAGase activity. CNS mastitis was most common in young cows during early lactation. Staphylococcus hyicus, S. simulans and S. epidermidis were the most frequently isolated CNS. Clinical symptoms were most severe with S. hyicus. Cure rates for CNS induced mastitis were high.     

Variation in the susceptibility of strains of Staphylococcus aureus to oxacillin, cephalothin, and gentamicin

Three cases of staphylococcal bacteremia caused by organisms that were inhibited by low concentrations of oxacillin, but were resistant to the killing effects of oxacillin, stimulated us to screen 60 clinical isolates of Staphylococcus aureus for their susceptibility to oxacillin, cephalothin, and gentamicin. All 60 strains were inhibited by low concentrations of the antibiotics. The antibiotics were bactericidal against 27 of the 60 strains and only bacteriostatic against the other 33 after 24 h of incubation. However, after 48 h of incubation, the antibiotics were also bactericidal against the latter group.     

Genetic susceptibility to the development of autoimmune disease

1. Autoimmune diseases are common conditions which appear to develop in genetically susceptible individuals, with expression of disease being modified by permissive and protective environments. Familial clustering and data from twin studies provided the impetus for the search for putative loci. Both the candidate gene approach in population-based case-control studies and entire genome screening in families have helped identify susceptibility genes in a number of autoimmune diseases. 2. After the first genome screen in type 1 (insulin-dependent) diabetes mellitus it seems likely that most autoimmune diseases are polygenic with no single gene being either necessary or sufficient for disease development. Of the organ-specific autoimmune diseases, genome screens have now been completed in insulin-dependent diabetes mellitus and multiple sclerosis. Furthermore, the clustering of autoimmune diseases within the same individuals suggests that the same genes may be involved in the different diseases. This is supported by data showing that both HLA (human leucocyte antigen) and CTLA-4 (cytotoxic T-lymphocyte-associated-4) appear to be involved in the development of insulin-dependent diabetes mellitus and Graves' disease. 3. Genome screens have also been completed in some of the non-organ-specific autoimmune diseases including rheumatoid arthritis, inflammatory bowel disease and psoriasis. Many candidate genes have also been investigated although these are predominantly in population-based case-control studies. 4. Substantial progress has been made in recent years towards the identification of susceptibility loci in autoimmune diseases. The inconsistencies seen between case-control studies may largely be due to genetic mismatching between cases and controls in small datasets. Family-based association studies are being increasingly used to confirm genetic linkages and help with fine mapping strategies. It will, however, require a combination of biology and genetics, as has been necessary with the major histocompatibility complex in insulin-dependent diabetes mellitus, to identify primary aetiological mutations.     

Hematologic and plasma chemistry values in captive psittacine birds

Organotin compounds including methyl- and butyltin species were determined in selected aquatic specimens (fish muscles, fish liver, mussels, algae) as well as in sediment and water from the mud flats of the German North Sea and the River Elbe. The concentration of tributyltin (TBT) ranged between 27-202 ng/g (fresh mass) in fish muscles, 54-223 ng/g (fresh mass) in fish liver, 10-25 ng/g (fresh mass) in common mussels and 42-97 ng/g (fresh mass) in bladderwrack. The concentration of total organotin compounds (mono-, di-, and trimethyltin + mono-, di-, and tributyltin) in water samples along the River Elbe up to the Elbe estuary ranged between 30-96 ng/l. Retrospective investigation of butylin compounds in mussel samples from the North Sea was performed by the analysis of cryogenically stored samples from 1985. A comparison of the results with that in muscles from 1993 shows that the total tin content and the TBT content decreased from 1985-1993 by a factor of 3.5 and 6.5, respectively. In addition estimated bioconcentration factors (BCF) for organotin compounds in samples from different trophic levels are presented.     

Esophagitis due to a herpesvirus associated with mortality in a psittacine aviary

In a disease outbreak at a psittacine aviary, eight Pionus sp. and Amazon parrots became sick. Three of four Amazon parrots died with severe esophagitis, and epithelial intranuclear inclusion bodies containing herpesvirus were prominent. Focal liver necrosis with rare hepatocyte intranuclear inclusion bodies were found in two of the dead Amazon parrots.     

Catechol-O-methyltransferase genotype and susceptibility to Parkinson's disease in Japan. Short communication

We report -108Met/Val polymorphism of the COMT gene in Japanese patients with Parkinson's disease (PD). The allele frequency for -108Val was higher in PD patients compared with controls, although the differences did not reach the statistical significance. However, the frequency of -108Val homozygotes was significantly higher in PD patients (56.8%) than in control subjects (44.2%), and heterozygotes of -108Met/Val were less in PD. COMT gene polymorphism may constitute a genetic risk factor for PD among Japanese.     

Alpha1-antichymotrypsin gene polymorphism and susceptibility to Parkinson''s disease

A clinical strain of Vibrio cholerae non-O1 non-O139 isolated in France produced a new beta-lactamase with a pI of 5.35. The purified enzyme, with a molecular mass of 33,000 Da, was characterized. Its kinetic constants show it to be a carbenicillin-hydrolyzing enzyme comparable to the five previously reported CARB beta-lactamases and to SAR-1, another carbenicillin-hydrolyzing beta-lactamase that has a pI of 4.9 and that is produced by a V. cholerae strain from Tanzania. This beta-lactamase is designated CARB-6, and the gene for CARB-6 could not be transferred to Escherichia coli K-12 by conjugation. The nucleotide sequence of the structural gene was determined by direct sequencing of PCR-generated fragments from plasmid DNA with four pairs of primers covering the whole sequence of the reference CARB-3 gene. The gene encodes a 288-amino-acid protein that shares 94% homology with the CARB-1, CARB-2, and CARB-3 enzymes, 93% homology with the Proteus mirabilis N29 enzyme, and 86.5% homology with the CARB-4 enzyme. The sequence of CARB-6 differs from those of CARB-3, CARB-2, CARB-1, N29, and CARB-4 at 15, 16, 17, 19, and 37 amino acid positions, respectively. All these mutations are located in the C-terminal region of the sequence and at the surface of the molecule, according to the crystal structure of the Staphylococcus aureus PC-1 beta-lactamase.     

In vitro susceptibility of clinical yeast isolates to fluconazole and terconazole

OBJECTIVE: Fifty clinical yeast isolates, representing equally Candida albicans, Candida krusei, Candida parapsilosis, Candida tropicalis, and Torulopsis glabrata, were tested in vitro for their susceptibility to terconazole and fluconazole. STUDY DESIGN: The minimal inhibitory concentrations of terconazole and fluconazole were determined by use of a proposed standardized broth macrodilution assay. Also, the response of selected yeast isolates to 25 micrograms of either drug was measured by agarose disk diffusion experiments. RESULTS: For all species the minimum inhibitory concentrations for terconazole were significantly lower than those for fluconazole (p < 0.05). In fact, for each individual isolate the minimum inhibitory concentration of terconazole was consistently lower than that of fluconazole. Differences in the geometric mean of terconazole and fluconazole minimum inhibitory concentrations were largest among C. krusei and T. glabrata, followed by C. parapsilosis, C. tropicalis, and C. albicans, in order of decreasing difference. Disk diffusion experiments suggested that terconazole is a more effective fungistatic agent than fluconazole is. CONCLUSION: Terconazole may be more effective than fluconazole against yeast species other than C. albicans.     

An outbreak of Pacheco's parrot disease in psittacine birds recently imported to Campania, Italy: isolation of psittacid herpesvirus 2

The authors describe an outbreak of Pacheco's Parrot Disease (PPD) which occurred in Italy in recently imported psittacine birds and was caused by Psittacid Herpesvirus type 2 (PsiHV2). The authors stress the different susceptibility to the disease in the species involved. This outbreak showed the failure of the vaccine prophylaxis that had been administered to the birds with ordinary commercial preparations containing Psittacid Herpesvirus type 1. The authors emphasize the necessity of producing a vaccine containing inactivated viruses of all known serotypes.     

Position of the mental foramen in adult black Zimbabwean mandibles: a clinical anatomical study

OBJECTIVE: To provide some anatomical information on the shape, size, and position of the mental foramen among Black Zimbabweans that could be used as reference material by dental and other health practitioners during clinical practice in Zimbabwe. DESIGN: Cross sectional anatomical study. SETTING: Department of Anatomy, Faculty of Medicine, University of Zimbabwe, Mount Pleasant, Harare, Zimbabwe. SUBJECTS: 32 mandibles derived from adult Black Zimbabweans. MAIN OUTCOME MEASURES: The shape of the mental foramen, its relation to the lower teeth and its position in relation to the mandibular symphysis, the posterior border of the ramus of the mandible, the lower border of the mandible, and the alveolar margin. RESULTS: The shape of the mental foramen was round in 14 out of 32 mandibles (43.8%) and was oval in the remaining 18 (56.3%). The percentage of occurrence of the mental foramen was highest below the lower second premolar tooth on the right side (position 4) and posterior to it on the left side (position 5). In the vertical plane, the mental foramen lay slightly below the midpoint of the distance between the lower border of the mandible and the alveolar margin (44.1% and 45.5% for the right and left sides respectively). In the horizontal plane, it lay approximately one quarter (27.3% for the right and 27.4% for the left sides) of the distance from the mandibular symphysis to the posterior border of the ramus of the mandible. CONCLUSION: The percentage distribution of the mental foremen in relation to the lower teeth in the adult Black Zimbabwean mandible was at variance with that of other population groups. However, the quantitative position of the mental foremen was bilaterally symmetrical in the adult Black Zimbabwean mandible. The latter observation is of clinical significance to dental and other health practitioners in Zimbabwe with regards to the achievement of effective mental nerve block anaesthesia and the prevention of damage to the mental nerve during surgical procedures on the lower jaw.     

Arabidopsis enhanced disease susceptibility mutants exhibit enhanced susceptibility to several bacterial pathogens and alterations in PR-1 gene expression

To identify plant defense responses that limit pathogen attack, Arabidopsis eds mutants that exhibit enhanced disease susceptibility to the virulent bacterial pathogen Pseudomonas syringae pv maculicola ES4326 were previously identified. In this study, we show that each of four eds mutants (eds5-1, eds6-1, eds7-1, and eds9-1) has a distinguishable phenotype with respect to the degree of susceptibility to a panel of bacterial phytopathogens and the ability to activate pathogenesis-related PR-1 gene expression after pathogen attack. None of the four eds mutants exhibited observable defects in mounting a hypersensitive response. Although all four eds mutants were also capable of mounting a systemic acquired resistance response, enhanced growth of P. s. maculicola ES4326 was still apparent in the secondarily infected leaves of three of the eds mutants. These data indicate that eds genes define a diverse set of previously unknown defense responses that affect resistance to virulent pathogens.     

Comparative susceptibility of Glossina longipennis and G. brevipalpis to pathogenic species of Trypanosoma

A 56-year-old woman was admitted to our hospital with the chief complaint of left back pain. We detected left pleural effusion on chest X-ray and performed chest drainage. No malignant cells were detected in the effusion. Chest CT demonstrated a tumor shadow over the left diaphragm and left pleural effusion 6 months later. She underwent en bloc resection of the tumor and left diaphragm. Histological evaluation revealed malignant fibrous histiocytoma (MFH). Recurrent tumors were found in the abdomen 8 months after the operation, and she underwent resection of the abdominal recurrent tumors. Histological evaluation of the recurrent tumors also showed MFH. The patient died 28 months after the first operation.     

Klebsiella pneumoniae clinical isolates: susceptibility to some antibiotics and surface hydrophobicity

The susceptibility of Klebsiella pneumoniae strains isolated from the respiratory tract (55), urinary tract (19) and other human body sites (8) to the antibiotics, amoxycillin/clavulanate, cefuroxime, ceftazidime, gentamicin, norfloxacin, colistine, cotrimoxazole and oxolinic acid, as well as their surface hydrophobicity, were studied. The strains expressed a very high sensitivity to the antibiotics (94.7-100%). The surface hydrophobicity of the strains was evaluated by means of three assays and was minimal. The hydrophobicity manifested by adherence to xylene ranged between 0 and 10% for 96.4% of the respiratory strains, and for 100% of the urinary and other sites. Weak binding of Congo red (10-29 micrograms/10(10) cells) showed 96.4% of respiratory isolates as well as 100% of the urinary and other strains. Results of the salt aggregation test showed that 96.4% of respiratory strains and 100% of urinary and other strains aggregated only at 1.5 M, 2 M or higher concentrations.     

Variation of nitrate reductase genes in selected grass species

In order to study the variation of nitrate reductase (NR) genes among grass species, gene number, intron size and number, and the heme-hinge fragment sequence of 25 grass species were compared. Genomic DNA cut with six restriction enzymes and hybridized with the barley NAD(P)H and NADH NR gene probes revealed a single NAD(P)H NR gene copy and two or more NADH NR gene copies per haploid genome in most of the species examined. Major exceptions were Hordeum vulgare, H. vulgare ssp. spontaneum, and Avena strigosa, which appeared to have a single NADH NR gene copy. The NADH NR gene intron number and lengths were examined by polymerase chain reaction amplification. Introns I and III appeared to be absent in at least one of the NADH NR genes in the grass species, while intron II varied from 0.8 to 2.4 kilobases in length. The NADH NR gene heme-hinge regions were amplified and sequenced. The estimated average overall nucleotide substitution rate in the sequenced region was 7.8 x 10(-10) substitutions/site per year. The synonymous substitution rate was 2.11 x 10(-9) substitutions/synonymous site per year and the nonsynonymous substitution rate was 4.10 x 10(-10) substitutions/nonsynonymous site per year. Phylogenetic analyses showed that all of the wild Hordeum species examined clustered in a group separate from H. vulgare and H. vulgare ssp. spontaneum.     

Phospholipid and cholesteryl ester transfer activities in plasma from 14 vertebrate species. Relation to atherogenesis susceptibility

1. In this study, the underlying mechanism of stimulation of respiratory burst by kazinol B, a natural isoprenylated flavan, in rat neutrophils in vitro was investigated. 2. Kazinol B concentration-dependently stimulated the superoxide anion (O2*-) generation, with a lag but transient activation profile, in neutrophils but not in a cell-free system. The maximum response (13.2+/-1.4 nmol O2*- 10 min(-1) per 10(6) cells) was observed at 10 microM kazinol B. 3. Pretreatment of neutrophils with phorbol 12-myristate 13-acetate (PMA) or formylmethionyl-leucyl-phenylalanine (fMLP) significantly enhanced the O2*- generation following the subsequent stimulation of cells with kazinol B. 4. Cells pretreated with EGTA or a protein kinase inhibitor staurosporine effectively attenuated the kazinol B-induced O2*- generation. However, a p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 and a phosphoinositide 3-kinase (PI3K) inhibitor wortmannin had no effect on the kazinol B-induced response. 5. Kazinol B significantly stimulated [Ca2+]i elevation in neutrophils, with a lag and slow rate of rise activation profile, and this response was attenuated by a phospholipase C (PLC) inhibitor U73122. Kazinol B also stimulated the inositol bis- and trisphosphate (IP2 and IP3) formation with a 1 min lag time. 6. The membrane-associated PKC-alpha and PKC-theta but not PKC-iota were increased following the stimulation of neutrophils with kazinol B. It was more rapid and sensitive in the activation of PKC-theta than PKC-alpha by kazinol B. Kazinol B partially inhibited the [3H]phorbol 12,13-dibutyrate ([3H]PDB) binding to the neutrophil cytosolic PKC. 7. Neither the cellular mass of phosphatidic acid (PA) and phosphatidylethanol (PEt), in the presence of ethanol, nor the protein tyrosine phosphorylation were stimulated by kazinol B. In addition, the kazinol B-induced O2*- generation remained relatively unchanged in cells pretreated with ethanol or a tyrosine kinase inhibitor genistein. 8. Collectively, these results indicate that the stimulation of the respiratory burst by kazinol B is probably mediated by the synergism of PKC activation and [Ca2+]i elevation in rat neutrophils.