Ionoregulatory and respiratory responses of brown trout, Salmo trutta, exposed to lethal and sublethal aluminium in acidic soft waters

Soft water acclimated (Ca(2+) 0.02 mM; Na(+) 0.03 mM; K(+) 0.01 mM; pH 7.0), cannulated brown trout (Salmo trutta) were exposed to various pH and aluminium (Al) regimes (pH 7.0, pH 5.0, pH 5.0 plus Al: 50, 25, and 12.5 μg l(-1)) for up to 5 days in order to determine (i) the sublethal concentration of Al at pH 5.0 for this species (ii) their ionoregulatory and respiratory status. No mortality or physiological disturbances were evident at pH 7.0 or pH 5.0. All trout died within 48 h at pH 5.0 in the presence of Al at 50 μg l(-1) and 67% died over the 5 day period at pH 5.0 in the presence of Al at 25 μg l(-1). Fish at these lethal Al concentrations showed significant decreases in arterial blood oxygen content (CaO2) but no changes in plasma osmolarity or the concentrations of plasma Na(+), K(+) and Cl(-). Physiological disturbance was more marked at the 50 μg l(-1) Al concentration. The surviving fish at 25 μg l(-1) showed few signs of physiological recovery while continually exposed to this regime. No fish died during the exposure to water of pH 5.0 containing 12.5 μg l(-1) Al, but physiological disturbance was still apparent. These sublethally-stressed trout showed a transient decline in the plasma concentrations of Na(+) and Cl(-1). Although CaO2 decreased, recovery was evident. The data suggest that in the brown trout, environmental Al concentration is as important as pH and calcium concentration in determining the physiological status of the fish.

Regulation of manganese peroxidase gene transcription by hydrogen peroxide, chemical stress, and molecular oxygen

The expression of manganese peroxidase (MnP) in nitrogen-limited cultures of the lignin-degrading fungus Phanerochaete chrysosporium is regulated at the level of gene transcription by H2O2 and various chemicals, including ethanol, sodium arsenite, and 2,4-dichlorophenol, as well as by Mn(II) and heat shock. Northern (RNA) blot analysis demonstrates that the addition of 1.0 mM H2O2 to 5-day-old cultures grown in the absence of Mn results in the appearance of mnp mRNA within 15 min. Higher levels of mnp mRNA are obtained with simultaneous induction by Mn and H2O2 than with H2O2 alone. Although neither MnP activity nor associated protein is detectable in H2O2-induced cultures grown in the absence of Mn, simultaneous induction with Mn and H2O2 results in a 1.6-fold increase in MnP activity compared with the MnP activity resulting from Mn induction alone. In the presence of Mn, purging of low-nitrogen cultures with 100% O2, in contrast to incubation under air, results in an increase in the accumulation of mnp mRNA and a 13-fold increase in MnP activity on day 5. However, in contrast to the effects of H2O2 and heat shock, O2 purging of Mn-deficient cultures results in negligible accumulation of mnp mRNA.

Comparative genomic hybridization, allelic imbalance, and fluorescence in situ hybridization on chromosome 8 in prostate cancer

Due to problems with primary tumor cell culture, conventional cytogenetics has yielded little insightful information on chromosomal alterations in prostate cancer. The primary aim of this study was to define the ability of comparative genomic hybridization (CGH) to detect and map genetic deletions in prostate tumors. A secondary aim was to apply multiple assays to individual tumors as a means of deciphering the mechanisms of genetic alterations in prostate cancer. CGH results were compared with allelic imbalance measurements at 29 distinct loci on chromosome 8 in 18 specimens (17 malignant and 1 benign). CGH detected no changes in cases where all informative PCR/RFLP loci were retained and detected all p arm deletions consisting of at least two loci. We estimate that in this study, the smallest deletions detected by CGH were approximately 20-30 cM. Physical mapping of subchromosomal arm deletions by CGH correlated well with allelic imbalance mapping by PCR/RFLP: The data agreed at 88% of loci on 8p and 92% of loci on 8q. Fluorescence in situ hybridization (FISH) with multiple centromere probes and DNA content flow cytometry (FCM) also was performed on selected specimens. FISH revealed two cases of chromosome 8 aneusomy. In these two cases and three others, CGH showed simultaneous p arm deletion and q arm gain, suggesting isochromosome 8q formation. Together, these data suggested that, simple chromosomal aberrations were responsible for allelic losses on 8p and allelic gains on 8q in a significant number of prostate tumors. We also used CGH to examine relative DNA sequence copy number throughout the genome. Changes frequently associated with 8p loss include gains of 8q and losses of 13q, 16p, 16q, 17p, 17q, 20q, and Y. Cases with 8p loss exhibited five times the number of alterations as did cases without 8p loss.

Chromosomal aneusomies detected by fluorescent in situ hybridization analysis in clinically localized prostate carcinoma

Fluorescent in situ hybridization using 12 chromosome enumeration probes (for chromosomes 4, 6, 7, 8, 9, 10, 11, 12, 17, 18, X and Y) was used to evaluate fresh tumor touch preparations from 40 randomly selected radical prostatectomy specimens. Of the tumors 16 (40%) contained chromosomal aneusomies. Chromosome 8 was aneusomic in 9 tumors (23%). Gain of chromosome 7 was observed in 8 tumors (20%). Chromosome 17 was aneusomic in 4 cases, and chromosomes 10, 11, 12, 18 and Y were each aneusomic twice. Loss of chromosome 9 was observed in 1 tumor. Chromosomes 4, 6, and X were never aneusomic. The percentage of monosomy 17 nuclei was 2 to 4 times the amount noted with the other autosomes for tumor and benign tissue. Computer analysis demonstrated that these signals contained twice the signal density and were significantly different (p < 0.0001) than the single diploid chromosome 17 signals. This result is consistent with homologous pairing of chromosome 17 in benign and neoplastic prostate tissue. Anomalies of chromosomes 8 and/or 7 were present in 14 of the 16 cases (88%) aneusomic by fluorescent in situ hybridization. High grade tumors were more likely to be aneuploid on fluorescent in situ hybridization (p < 0.001). Tumors with chromosome 8 aneusomies were of higher stage (p < 0.05). Fluorescent in situ hybridization is more sensitive than flow cytometry for the detection of aneusomy/aneuploidy. The prognostic relevance of these findings will require further investigation.

Double-masked placebo-controlled trial of precision spectral filters in children who use coloured overlays

We selected 68 children who reported benefit from individually chosen sheets of coloured plastic placed upon the page when reading, and who used these regularly without prompting. These children viewed text illuminated by coloured light in an apparatus that allowed the separate manipulation of hue (colour) and saturation (depth of colour), at constant luminance. Many of the children reported improvements in perception when the light had a chromaticity within a limited range, which was different for each individual. A pair of plastic spectacle lenses ('experimental' lenses) was dyed so as to provide the appropriate chromaticity under conventional white (F3) fluorescent light. An additional pair was prepared having very similar colour but with a chromaticity outside the range in which perception was reported to improve ('control' lenses). Each pair was provided for 1 month in random order. The children kept diaries (36 completed) recording symptoms of eye-strain and headache. The children and those responsible for their assessment were unable reliably to distinguish 'experimental' from 'control' lenses. Nevertheless, symptoms were less frequent on days when the 'experimental' lenses were worn (P < 0.003).

Aneuploidy and aneusomy of chromosome 7 detected by fluorescence in situ hybridization are markers of poor prognosis in prostate cancer

Fluorescence in situ hybridization is a new methodology which can be used to detect cytogenetic anomalies within interphase tumor cells. We used this technique to identify nonrandom numeric chromosomal alterations in tumor specimens from the poorest prognosis patients with pathological stages T2N0M0 and T3N0M0 prostate carcinomas. Among 1368 patients treated by radical prostatectomy, 25 study patients were ascertained who died most quickly from progressive prostate carcinoma within 3 years of diagnosis and surgery. Tumors from 25 control patients who survival for more than 5 years and who were matched for age, tumor histological grade, and pathological stage also were evaluated. The tumors from all 25 (100%) poor prognosis patients and from 11 of 25 (44%) control patients were found to be aneuploid by fluorescence in situ hybridization (P < 0.0001). Alterations of chromosome 7 were observed in 24 of the tumors (96%) from the poor prognosis patients versus 3 tumors (12%) from the control group (P < 0.0001). Moreover, a characteristic aneuploidy pattern with multiple abnormal chromosomes and a hypertetrasomic population was generally found in tumors from the poor prognosis patients. This preliminary study suggests that fluorescence in situ hybridization studies of prostate cancer specimens may help to identify those patients at highest risk for early cancer death.

Catabolic hormones alone fail to reproduce the stress-induced efflux of amino acids

OBJECTIVE

To determine the impact of catabolic hormones on the pattern of amino acid efflux from human skeletal muscle during stress.

DESIGN

Cohort analytical study.

SETTING

Burn intensive care unit and clinical research facility at a university hospital.

PATIENTS

Five patients with severe burns and five healthy volunteers of similar size and age.

INTERVENTIONS AND MEASUREMENTS

The net balance of amino acids across the leg was determined in five healthy volunteers prior to and following a 2-hour infusion of the catabolic hormones epinephrine, cortisol, and glucagon into the femoral artery. These results were compared with amino acid net balance measurements in five severely burned patients.

RESULTS

Hormonal simulation of stress in the normal volunteers increased glutamine efflux from the leg to an extent similar to that of the burn patients. Alanine efflux, however, was not affected by the hormonal infusion. Because alanine efflux constituted a major proportion of the total peripheral amino acid catabolism in the burn patients, there was significantly less total amino acid nitrogen loss from the healthy volunteers receiving the stress hormones.

CONCLUSIONS

Catabolic hormones alone fail to reproduce the stress-induced pattern and quantity of amino acid efflux from human skeletal muscle. This discrepancy is largely due to an unresponsiveness of alanine to hormonally induced muscle protein catabolism.

Arthrography of the contralateral, asymptomatic wrist in patients with unilateral wrist pain

To determine the significance of arthrographic abnormalities in patients with unilateral wrist pain, the authors compared the prevalence and site of intra-articular ligament perforation in asymptomatic and symptomatic wrists of the same group of patients and correlated asymptomatic perforation with age, hand dominance and hand overuse. Thirty-seven patients (29 men and 8 women ranging in age from 19 to 61 years) who had unilateral wrist pain and positive arthrographic findings for the symptomatic wrist underwent radiocarpal arthrography of the asymptomatic wrist. Three radiologists blinded as to the clinical findings examined the images for perforation in the triangular fibrocartilage complex, the lunotriquetral ligament and the scapholunate ligament. Intra-articular ligament perforations were found in 33 (89%) of the 37 asymptomatic wrists. Seventeen (46%) of the 37 patients had symmetric sites of perforation in the two wrists. Perforation of the triangular fibrocartilage complex occurred in 22 (59%) and 19 (51%) of the symptomatic and asymptomatic wrists respectively, of the lunotriquetral ligament in 13 (35%) and 7 (19%) respectively and of the scapholunate ligament in 13 (35%) and 11 (30%) respectively. No significant correlation between asymptomatic perforation and age or hand overuse was found (chi 2 test, Fisher's exact test). The authors conclude that asymptomatic perforation is common, even in young patients, so ligament perforation is not necessarily the cause of wrist pain in patients with such pain. However, for patients with the appropriate clinical findings, arthrography can be used to confirm or exclude ligament perforation.

Exercise-induced upper extremity rhabdomyolysis and myoglobinuria in shipboard military personnel

During a 6-month Amphibious Task Force deployment to the Mediterranean Sea, five sailors and Marines were admitted to the ship's ward with severe upper extremity pain, elevated serum muscle enzymes, and a urinalysis dip positive for blood in the absence of microscopic hematuria-a finding highly suggestive of myoglobinuria. Each patient had begun a vigorous upper-extremity work-out program in the ship's weight room 1 to 3 days prior to development of symptoms. All responded well to vigorous intravenous hydration, mannitol diuresis, alkalinization of the urine, and skeletal muscle rest. No patient developed acute tubular necrosis. With increasing emphasis on physical fitness and body building, this condition is likely to become more frequent. The most important preventive measure is gradual conditioning. Awareness of this entity and early aggressive management are necessary to avoid the potentially severe complication of renal failure.

Potential markers of prostate cancer aggressiveness detected by fluorescence in situ hybridization in needle biopsies

Fluorescence in situ hybridization (FISH) with centromere-specific probes for chromosomes 7, 8, 11, and 12 was used to evaluate multiple 18-gauge needle biopsy cores from 50 randomly selected radical prostatectomy specimens. FISH analysis detected 26 diploid (52%), 7 tetraploid (14%), and 17 aneuploid tumors (34%). The FISH results were concordant with flow cytometric (FCM) DNA content measurements of the corresponding prostatectomy specimens for 31 tumors. For the 19 FISH/FCM discordant tumors, FISH was more sensitive than FCM for detecting ploidy anomalies. Common numerical chromosome alterations were gains of chromosomes 7 and 8, which were found in 13 (76%) and 10 (59%) aneuploid tumors, respectively. Gain of chromosome 7 was strongly associated with higher Gleason score (> or = 8) (P < 0.0001) and with advanced tumor pathological stages (stages T3 + T4; P < 0.01). Gain of chromosome 8 also correlated with higher Gleason score (P < 0.01). FISH showed intratumoral ploidy heterogeneity in 3 of 41 (7%) studied tumors. Among 17 noncancerous adjacent tissue specimens, chromosome alterations were observed in one, which contained high-grade prostatic intraepithelial neoplasia. Combined FISH and fluorescent leukocyte common antigen staining showed that infiltrating leukocytes do not contribute to the observed gains of chromosomes 7 and 8 in prostate cancer tissue. These results demonstrate that (a) FISH analysis of prostate needle biopsy-sized specimens can be a practical, sensitive method for determination of nuclear ploidy and numerical chromosome alterations; and (b) gains of chromosomes 7 and 8 are common numerical alterations of prostate cancer cells and may be potential markers of tumor behavior and patient prognosis.

Intraductal papillary carcinoma of the pancreas

We report a case of intraductal papillary adenocarcinoma of the distal pancreatic duct. Although a rare subgroup of exocrine pancreatic tumors, their diagnosis is an important one in view of their favorable prognosis with pancreatectomy. Because of the established behavior of villous tumors of the colon, to which they are similar histologically, these tumors should be resected, even if biopsy shows benign disease. Patients should be followed radiologically for recurrence or the development of new adenoma following resection.

Characterisation of angiotensin II binding to glomeruli from rainbow trout Oncorhynchus mykiss adapted to fresh water and seawater

Specific binding of 125I-[Asn1, Val5]-angiotensin II to isolated glomeruli of freshwater-adapted and seawater-adapted rainbow trout, Oncorhynchus mykiss, reached a plateau after 20 min at 10 degrees and was displaced by nonradiolabelled [Asn1, Val5]-angiotensin II. Seawater adaptation increased the rate of dissociation of 125I-[Asn1, Val5]-angiotensin II from putative receptors. Competitive binding experiments revealed a single population of high-affinity receptors with a KD 0.3-0.4 x 10(-10) M, which was unchanged by seawater adaptation. Seawater adaptation did, however, reduce the density (Bmax) of the binding sites, which may reflect down-regulation by the higher plasma concentration of angiotensin II in seawater-adapted trout.

Persistence of Mycobacterium bovis in cattle

Badgers represent a wildlife reservoir for bovine tuberculosis in Britain, which persists in the south west despite almost 20 years of badger control. The influence of landscape structure on patterns of badger urinatory behaviour may be one reason for the localized persistence of the disease in cattle within the region.

The 5' flanking region of the rat beta 3-adrenergic receptor gene: divergence with the human gene and implications for species-specific gene expression

beta 3-adrenergic receptor mRNAs exhibit species-specific expression (human vs. rodent) in distinct anatomical regions and appear to be expressed abundantly within rodent adipose tissue, but only at low levels within corresponding human tissues. In order to determine the genetic basis of the differential expression of the rat and human beta 3-adrenergic receptor genes, we cloned and sequence the rat gene and compared the 5' flanking regions of the two genes to identify potential discriminators in transcriptional regulation. We have found that the rat and human beta 3-adrenergic receptor 5' flanking regions are only 67% similar, unlike the close sequence similarity observed between the coding blocks (> 90%) and also observed between species for the 5' flanking regions of other beta-adrenergic receptor subtype genes (> 90%). In addition, the rat beta 3-adrenergic receptor gene lacks the four potential cAMP responsive elements identified within the 5' flanking region of the human receptor gene. The striking divergence in regulatory sequences between the rat and human beta 3-adrenergic receptor genes may potentially explain the differences in species-specific expression and tissue localization of the rat and human receptor mRNAs.

Durable remissions following prolonged plasma exchange in thrombotic thrombocytopenic purpura

We evaluated the efficacy of prolonged plasma exchange (PEX) for attaining durable remissions in thrombotic thrombocytopenic purpura (TTP). A recent review using steroids or PEX in initial management showed an 80% response rate but produced a relapse rate of 67-84%. Records of 50 patients starting PEX treatment for TTP/HUS were reviewed to identify and select those whose course of treatment had ended over 1 year earlier, whether or not the result was satisfactory. Records were evaluated for outcome, especially remission associated with treatment by "prolonged" plasma exchange. "Prolonged" was defined as continuing PEX beyond the stage where a normal platelet count was attained and until evidence of hemolysis was "minimal or at least compensated." If disease activity as judged by the criteria of hemolysis became accelerated or resumed, PEX was increased by volume of FFP (e.g., from 3 to 4 L) or rate (from less than daily to daily). Of 50 consecutive patients treated by PEX for TTP/HUS there were 40 cases after which at least one year had passed since the end of treatment. These 40 patients were evaluated for the results of treatment by PEX. Eight failed to achieve remission, dying in hospital within 1 month of admission. Twenty-eight achieved remission, sustained for 1 year or more in all. These are the reasons for our enthusiasm about this report. Four achieved remission lasting less than 1 year. Splenectomy was performed to obtain a sustained remission in one patient following administration of three 2 mg doses of vincristine and two relapses.(ABSTRACT TRUNCATED AT 250 WORDS)

Further characterization of 19 cases of rea(21q21q) and delineation as isochromosomes or Robertsonian translocations in Down syndrome

We have used 9 conventional RFLPs and 6 dinucleotide repeat polymorphisms on chromosome 21q to demonstrate that 17 of 19 cases of rea(21q21q) were consistent with isochromosomes i(21q) with the remaining 2 being true Robertsonian translocations. Eight of the 17 isochromosomes were of maternal origin and 9 cases were paternally derived. The 2 Robertsonian translocations were both maternally derived. Of the 17 isochromosomes, 7 were dicentric [idic(21q)] and 10 were monocentric [i(21q)]. Both rob(21q21q) were monocentric. Our findings agree with those made in 17 previously published cases of rea(21q21q). The parental origins of the i(21q) were equally divided between maternal (n = 17) and paternal (n = 15) origins. All 4 true rob(21q21q) reported to date are of maternal origin. Collectively, it appears that most homologous rearrangements of chromosome 21 are isochromosomes and only a small proportion are consistent with true Robertsonian translocations.

Medicolegal aspects of treating drug and alcohol addiction

The authors present an overview of different areas of interface between medicine and the law, applicable to the treatment of patients with drug and alcohol problems. The five case reports are a sample of the medicolegal issues that can arise in the treatment of drug addicts and alcoholics.

Novel O-D-galacturonoyl esters in the pectic polysaccharides of suspension-cultured plant cells

Driselase digestion of uronate-6-14C-labeled primary walls of cultured spinach (Spinacia oleracea L.) cells yielded about 18 novel uronate-containing compounds, most of which could be hydrolyzed by cold dilute alkali to yield oligo-[14C]galacturonides. One typical Driselase digestion product (compound 17) yielded alpha-(1-->4)-D-[14C]galacturonotriose(GalA3) upon very mild treatment with alkali (50% yield of GalA3 in 7.2 min at pH 11 and 25 degrees C). One of the three galacturonate residues in compound 17 was reducible to a galactose residue with sodium borohydride, indicating that that GalA residue was esterified, via its--COOH group, to a putative alcohol. Compound 17 had a higher mobility than GalA3 on paper chromatography, indicating that the putative alcohol was relatively nonpolar. The putative alcohol could not have been methanol because Driselase readily hydrolyzed mono-, di-, and trimethyl esters of GalA3 to yield free galacturonic acid. Another Driselase digestion product (compound 12) was a derivative of GalA3 that apparently possessed two nonpolar esterified substituents: one about as labile as in compound 17, and the other approximately 10 times more stable. Compounds 12 and 17 could not labeled by in vivo feeding of [U-14C]cinnamate, suggesting that they were not phenolic conjugates. Similar but chromatographically distinguishable uronate-14C-labeled esters were obtained by Driselase digestion of walls of cultured carrot (Daucus carota L.), Paul's Scarlet rose (Rosa sp.), and tall fescue (Festuca arundinacea Schreber) cells. In spinach, the novel compounds constituted about 5% of the total galacturonate residues of the cell wall. The observations suggest that pectic polysaccharides are linked, via O-D-galacturonoyl ester bonds, to relatively hydrophobic constituents of the primary cell wall. Their possible role in wall architecture is discussed.

Characterization of putative glomerular receptors for angiotensin II in the rainbow trout Oncorhynchus mykiss using the antagonists Losartan, PD 123177, and saralasin

Isolated glomeruli from the rainbow trout Oncorhynchus mykiss have been examined for the presence of receptors specific for angiotensin II (AII). Specific binding of 125I-Asp1Val5-AII was saturable, plateaued after 20 min, and increased with glomerular protein. Saralasin (Sar1Val5Ala8-AII), a nonselective peptide AII receptor antagonist of AII binding to mammalian tissues, was a poor inhibitor of 125I-Asn1Val5-AII binding to trout glomeruli. However, the nonpeptide antagonist, Losartan (= DuP 753), which is specific for AII subtype AT1 receptors in mammalian tissues, was an effective inhibitor of binding of both 125I-Asp1Val5-AII and 125I-Asn1Val5-AII to trout glomeruli. The IC50 for Losartan inhibition of binding of Asp1Val5-AII was 1.25 +/- 0.07 x 10(-8) M while that for inhibition of binding of Asn1Val5-AII was 2.73 +/- 0.45 x 10(-8) M. Statistical analysis of logistic curve fits confirmed the easier displacement of Asp1Val5-AII than of Asn1Val5-AII. PD 123177, a nonpeptide antagonist specific for AII subtype AT2 receptors in mammalian systems, was ineffective as an antagonist of AII binding to trout glomeruli. These results are consistent with the presence of a specific AII receptor in the trout glomerulus and imply a novel receptor configuration.

Badgers (Meles meles), cattle and bovine tuberculosis (Mycobacterium bovis): a hypothesis to explain the influence of habitat on the risk of disease transmission in southwest England

Badgers are believed to be responsible for a high proportion of the cases of bovine tuberculosis in cattle in southwest England where, despite the onset of badger control operations in 1975, comparatively high numbers of cattle continue to fail the tuberculin test. To determine why the disease remains a problem in these areas, data on badger densities and patterns of land use were examined. Areas subject to repeated badger control operations had greater landscape heterogeneity and a higher density of linear habitat features. These habitat features were not related to badger density, measured as the mean number of social groups per square kilometre. Environmental contamination by infected badger urine is thought to be the main mode for the transmission of bovine tuberculosis. Field studies in an area with tuberculosis in both badgers and cattle showed that badgers may urinate on pasture after crossing through a linear feature, and that the number of these crossing-point urinations increases with the number of linear features crossed. The hypothesis is presented that these crossing-point urinations are a major source of bovine tuberculosis infection in cattle, and that areas with increased numbers of linear features have greater levels of contamination of pasture with badger urine and hence increased opportunities for disease transmission.

Management of ventilation tubes: preventing premature extrusion

The Goode T-tube provides a safe and efficient method of ventilating the middle ear space for an extended period of time without random premature extrusion. Each patient needs to be evaluated and followed closely while these tubes are in position. The criteria for the length of time that tubes are retained and the low complication rate are presented. Selective measures for removal of these tubes have provided a reasonable, safe and cost effective means of handling chronic secretory otitis.