Mating disruption by a synthetic sex pheromone in the white grub beetle Dasylepida ishigakiensis (Coleoptera: Scarabaeidae) in the laboratory and sugarcane fields.

A serious sugarcane pest, Dasylepida ishigakiensis, remains in the soil during most of its life cycle except for a short period for mating. Mating disruption by an artificial release of the sex pheromone (R)-2-butanol (R2B), therefore, may be a feasible method to control this pest. We examined the effects of artificial release of R2B and its related compounds, (S)-2-butanol (S2B) and the racemic 2-butanol (rac-2B), on the mating success of this beetle both in the laboratory and in the field. In flight tunnel experiments, almost all males orientated towards a R2B-releasing source and 40% of them landed on the source. When the atmosphere was permeated with R2B, the frequency of males landing on the model was significantly reduced. Both rac-2B and S2B were less effective, but substantial reduction in landing success by males was achieved at higher rac-2B concentrations. R2B released from polyethylene dispensers in sugarcane plots greatly reduced not only the proportion of females mated with males but also the number of males caught by R2B-baited traps, indicating that male mate-searching behaviour was strongly affected by the released R2B. Similar inhibitory effects on male behaviour were also observed when tube- or rope-type dispensers released high rac-2B concentrations in the field. These results indicate that it would be highly possible to control D. ishigakiensis through the disruption of the sexual communication by releasing either synthetic R2B or rac-2B.

Coma due to ciguatera poisoning in Rhode Island.

A patient is presented who developed an acute gastrointestinal and neurologic syndrome progressing to coma after ingestion of a fish soup made in Rhode Island. Laboratory studies confirmed the clinical diagnosis of ciguatera poisoning. Physicians should be aware of the diagnostic features of this disease even in non-endemic areas.

Inductive effect on hepatic enzymes and toxicity of congeners of PCBs and PCDFs.

The present paper describes a marked induction of liver microsomal cytochrome P-450 and cytosolic DT-diaphorase to cause possible disorder of steroid homeostasis and promotion of carcinogenicity of 4-nitroquinoline N-oxide (4-NQO) in rats by pretreatment with 3,4,5,3',4'-pentachlorobiphenyl (PenCB) or 2,3,4,7,8-pentachlorodibenzofuran (PenCDF). The animals were sacrificed 5 days after the pretreatment. These induction experiments showed that 7 alpha-hydroxylation of both progesterone and testosterone in liver microsomes was selectively increased to a great extent, but hydroxylations at the 2 alpha-, 6 beta- and 16 alpha-positions were depressed, together with 5 alpha-reduction. From the same microsomes, three of the strongly induced P-450 isozymes, i.e., high- and low-spin P-448s and P-452, were purified. The last isozyme was most responsible for 7 alpha-hydroxylation of testosterone. The pretreatment, also increased activity of DT-diaphorase and reduction of 4-NQO about 10-fold in liver 9000g supernatants. This reduction of 4-NQO was solely catalyzed by DT-diaphorase and the only product was 4-hydroxylaminoquinoline N-oxide, a proximate carcinogen, indicating that the pretreatment strongly increased production of a proximate carcinogen from 4-NQO. Such an enhancement of the metabolic activation of 4-NQO by the pretreatment was also observed to some extent in the lung and the skin. Persistency of PenCB and PenCDF in the liver of rats was also discussed.

Purification and characterization of two forms of chicken liver cytochrome P-450 induced by 3,4,5,3',4'-pentachlorobiphenyl.

3,4,5,3',4'-Pentachlorobiphenyl (PenCB), one of the most potent 3-methylcholanthrene (MC)-type inducers of hepatic enzymes in animals, caused a remarkable induction of liver microsomal monooxygenases, particularly 7-ethoxyresorufin (7-ER) O-deethylase, benzo(a)pyrene (BP) 3-hydroxylase, and testosterone 16 alpha-hydroxylase in chickens, but not NADPH-cytochrome c(P-450) reductase and cytochrome b5. Two forms of cytochrome P-450 (P-450) in liver microsomes of PenCB-treated chickens were purified and characterized. The absorption maxima of the CO-reduced difference spectra of both enzymes (chicken P-448 L and chicken P-448 H) were at 448 nm. From the oxidized form of their absolute spectra, chicken P-448 L was a low-spin form and chicken P-448 H was a high-spin form. They had molecular masses of 56 and 54 kDa, respectively. In a reconstituted system, 7-ER O-deethylation, BP 3-hydroxylation, and testosterone 16 alpha-hydroxylation were catalyzed at high rates by chicken P-448 L but not by chicken P-448 H. Chicken P-448 L also catalyzed N-demethylation of aminopyrine, benzphetamine, and ethylmorphine with relatively low activity. On the other hand, chicken P-448 H functioned only in catalyzing estradiol 2-hydroxylation. These results were supported by an inhibition study of microsomal monooxygenases using an antibody against each enzyme. Immunochemical studies revealed that the enzymes differ from each other but are both inducible by PenCB-treatment. Chicken P-448 L and chicken P-448 H respectively comprise about 82 and 7% of the total P-450 content in chicken liver microsomes.

Snake venom proteinase inhibitors. III. Isolation of five polypeptide inhibitors from the venoms of Hemachatus haemachatus (Ringhal's corbra) and Naja nivea (Cape cobra) and the complete amino acid sequences of two of them.

Five proteinase inhibitors which all inhibit the activity of bovine trypsin [EC 3.4.21.4] were isolated from African Elapid venoms of Hemachatus haemachatus (HHV, Ringhal's cobra) and Naja nivea (NNV, Cape cobra). All the inhibitors were essentially homogeneous by polyacrylamide gel electrophoresis in the presence or absence of sodium dodecylsulfate. Amino acid analysis and terminal analysis also supported their chemical homogeneities, except for one of the two inhibitors from Hemachatus haemachatus venom. The isolated inhibitors had a molecular weight of about 6,500, consisting of 52 to 57 amino acid residues, and they were all devoid of tryptophan. However, their amino acid compositions differed from each other. One of the three inhibitors isolated from Naja nivea venom, designated NNV inhibitor Ia, was unique, in that 4 half-cystinyl residues per mole fof the polypeptide were present, whereas all the others contained six residues. Of the isolated proteinase inhibitors, the complete amino acid sequences of two major inhibitors were established by manual and automatic Edman degradations and standard enzymatic techniques. Each of the inhibitors, designated HHV inhibitor II and NNV inhibitor II, consisted of 57 amino acid with arginine and glycine at the NH2- and COOH-termini, respectively. Both contained six half-cystines in disulfide linkages, and their overall amino acid sequences were similar, showing 91% homology. The two inhibitors differed in sequence by only five amino acid replacements, Asp-3 to Arg; Tyr-17 to Arg; Leu-25 to Arg; Gln-32 to Glu; and Arg-52 to His, in the 57 residue peptide chain. Comparing the amino acid sequences of these two cobra venom inhibitors with those of Russell's viper venom inhibitor II and bovine pancreatic trypsin inhibitor (BPTI), about 50% homology was found in their sequences. The 6 half-cystinyl residues of these inhibitors were in the same linear positions. Moreover, the regions which are structurally and functionally important in the well-known BPTI molecule were found with extremely high sequence homology in the cobra venom inhibitors. These findings strongly suggest that the cobra venom inhibitors as well as Russell's viper inhibitor II have very similar conformations to that established for BPTI.

Comparison of DT-diaphorases purified from the liver cytosol of untreated, and 3,4,5,3',4'-pentachlorobiphenyl- and 3-methylcholanthrene-treated rats.

DT-Diaphorase purified from the liver cytosol of rats treated with a highly toxic PCB congener, 3,4,5,3',4'-pentachlorobiphenyl (PenCB), was compared to those from 3-methylcholanthrene (MC)-treated and untreated rats. Treatments with PenCB and MC resulted in about 8- and 7-fold increases of cytosolic DT-diaphorase activity, respectively. Purification of the enzyme preparations from untreated, and PenCB- and MC-treated rats were conducted by using DE-52, DEAE-Sephadex A-50, hydroxylapatite, and Bio-Gel P-150 column chromatographies. Both Sephadex G-100 gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that all of the final preparations from the three origins were homogeneous and had the same molecular weight of 59,000, consisting of two subunits with molecular weights of 30,000. Further studies on amino acid composition, Km value, optimum pH, and catalytic activities for various substrates also indicated that both PenCB- and MC-inducible DT-diaphorases were identical with that from the untreated rats. All three DT-diaphorases contained about 2 mol of FAD per mol of enzyme. Partial digestion of the enzymes by trypsin and subsequent analysis by HPLC revealed that the three preparations were indistinguishable. The identity among the three purified DT-diaphorases was finally confirmed by Ouchterlony immunodiffusion employing anti-serum raised against each enzyme preparation.

Amino acid sequence of Japanese horseshoe crab (Tachypleus tridentatus) coagulogen B chain: completion of the coagulogen sequence.

The complete amino acid sequence of the B chain derived from Tachypleus tridentatus coagulogen was determined. It consisted of a total of 129 amino acid residues with a NH2-terminal glycine and COOH-terminal phenylalanine. Sequence studies of the whole B chain and the fragments obtained from the digests with trypsin, alpha-chymotrypsin, thermolysin and Staphylococcal protease V8 showed the following sequence: (sequence; see text) These structural studies of the B chain and the previously established amino acid sequences of the A chain and peptide C derived from T. tridentatus coagulogen, now make it possible to complete the whole sequence of coagulogen consisting of 175 amino acid residues with the molecular weight of 19,723.

Immunologic basis for the pathogenesis of pterygium.

We examined surgically excised pterygial tissues from 26 patients for the various immunoglobulin classes by direct immunofluorescence. Of the 26 patients, 19 (73.1%) showed positive staining with goat anti-human IgG fluorescein-labeled antibody. Direct immunofluorescence with goat anti-human IgE fluorescein-labeled antibody was found in all 26 samples, varying in fluorescent intensity from 1+ to 4+. Routine histologic staining disclosed an infiltration of small lymphocytes and plasma cells into the pterygium. These results suggest that an immunologic mechanism, possibly Type 1 hypersensitivity, may contribute to the pathogenesis of pterygium.

A rapid, simplified enzyme immunoassay stick test for the detection of ciguatoxin and related polyethers from fish tissues.

A simplified and rapid enzyme immunoassay stick test is presented in this study. The salient feature of this test is the use of a coating (Liquid Paper) on the stick to adsorb the lipid ciguatoxin and its related polyether toxins onto the stick. This rapid solid phase stick test has been able to differentiate clinically implicated fishes (14 samples) from non-toxic (60 samples) with P less than 0.005. Comparison of the stick test with the enzyme immunoassay procedure with the positive fish samples demonstrated a good correlation. All samples were positive by both procedures. Further comparison of the stick test, enzyme immunoassay and the mouse bioassay with unknown fish samples showed good relationships between the three procedures. Examination of 71 Seriola dumerili, a fish generally implicated in ciguatera poisoning, with the stick test procedure showed that 89% of the fishes were non-toxic and thus consumed without any incidence of ciguatera poisoning. Analysis of graded concentrations of ciguatoxin, in ng/ml of methanol, showed a typical immunological precipitation pattern. The stick test as conceived is simple and rapid, while retaining its sensitivity and specificity to detect ng levels of ciguatoxin and its related polyether toxins. It is suggested that the stick test will be valuable in the screening of ciguatoxin and related polyether toxins in contaminated fish tissues.

Variations in symptomatology of ciguatera poisoning.

Ciguatera poisoning reports were examined for patterns of symptomatology when different types of fishes were consumed. Consumption of surgeon fish (Ctenochaetus strigosus), amberjack (Seriola dumerili) and jack (Caranx sp.) resulted in different symptom profiles with a number of statistically significant differences in the reported frequencies of specific symptoms. The results support the contention that the large variability in symptoms associated with ciguatera poisoning is caused by several closely related but distinct toxins.

Aplysiatoxin and debromoaplysiatoxin as the causative agents of a red alga Gracilaria coronopifolia poisoning in Hawaii.

The causative toxins of a red alga Gracilaria coronopifolia poisonings in Hawaii, which broke out in succession in September of 1994, were studied. Two major toxins were isolated from both extracts of the two original algal samples which caused separate poisonings. By spectroscopic method, these toxins were shown to be completely identical with aplysiatoxin and debromoaplysiatoxin which have previously been obtained from the sea hare and also from blue green algae. The human symptoms and the amount of these toxins in the original algal samples indicate that aplysiatoxin and debromoaplysiatoxin were the causative agents of the human poisoning incidents. This is the first reported case of the implication of aplysiatoxin and debromoaplysiatoxin in food poisoning. The existence of these toxins in the residue of algae washed in saline was confirmed by HPLC analysis. Furthermore, we observed blue-green algal parasitism on the surface of the toxic G. coronopifolia. Therefore, epiphytic organisms such as blue-green algae might be the true origin of the toxins in G. coronopifolia.

The first reported case of human ciguatera possibly due to a farm-cultured salmon.

This study is an individual case report of an imported cultured salmon which may have caused ciguatera. The individual's documented clinical symptoms, along with our immunological tests and bioassays (hemolytic, mouse toxicity and guinea-pig atrial assays) of the salmon extracts, strongly suggest that the salmon may have contained a ciguatoxin-like toxin (or toxins). The unique ability of the toxin(s) to block the sodium channel of the guinea-pig atrium, however, distinguishes it from ciguatoxin-1 isolated from moray eel liver.

A rapid enzyme-immunoassay for the detection of ciguatoxin in contaminated fish tissues.

An enzyme-immunoassay procedure for the detection of ciguatoxin has been developed using the sheep anti-ciguatoxin serum described earlier in the radioimmunoassay method for ciguatoxin. In the enzyme-immunoassay procedure, the sheep anti-ciguatoxin was coupled to horseradish peroxidase. Analyses of fish tissues showed that the enzyme-immunoassay procedure distinguished between clinically documented toxic and nontoxic tissues (P less than 0.001). Comparisons of the enzyme-immunoassay method with the radioimmunoassay for ciguatoxin and with a mouse bioassay demonstrated significant associations (P less than 0.001 and P less than 0.01, respectively). Preliminary studies showed that purified ciguatoxin inhibited the binding of sheep anti-ciguatoxin horseradish peroxidase to toxic fish tissues. Results suggest that the enzyme-immunoassay procedure may be valuable for routine direct assessment of ciguatoxin in fish tissues because of its practicality, sensitivity and specificity.

Gambierdiscus toxicus in gut content of the surgeonfish Ctenochaetus strigosus (herbivore) and its relationship to toxicity.

Flesh of surgeonfish, Ctenochaetus strigosus, obtained from corresponding catches of C. strigosus implicated in ciguatera poisoning outbreaks was examined for ciguatoxin and related polyethers by the stick test enzyme immunoassay. Simultaneously, gut contents of the fish were examined under phase microscopy for the presence of Gambierdiscus toxicus. Eighty-seven per cent of the fish were stick EIA positive, while 98% were positive for G. toxicus in gut contents. The data obtained suggest a relationship between G. toxicus in gut content and tissue toxicity levels. This is in agreement with previous studies which demonstrated a relationship between G. toxicus in fish gut content and toxicity of the flesh to animals and humans.

Clinical and laboratory findings implicating palytoxin as cause of ciguatera poisoning due to Decapterus macrosoma (mackerel).

A near fatal case of ciguatera-related intoxication following consumption of smoked Decapterus macrosoma is documented. In addition to some of the hallmark symptoms of ciguatera poisoning, the patient exhibited acute respiratory distress and severe muscle spasms. Laboratory results showed large elevations in a number of blood enzymes, indicative of muscle damage. The responsible agent was extracted from corresponding fish samples and identified as palytoxin.

Comparison of three different assays for the assessment of ciguatoxin in fish tissues: radioimmunoassay, mouse bioassay and in vitro guinea pig atrium assay.

Moderate correlation was shown between the following tests: RIA: mouse bioassay (r = 0.58); RIA: guinea pig atrium assay (r = 0.62); guinea pig atrium assay: mouse bioassay (r = 0.62). All three assay procedures showed good correlation when ciguatoxin was present in tissues in high concentrations. The results also suggest that more than one structurally related toxin may be present in the fish tissues.

Kahalalide K: A new cyclic depsipeptide from the hawaiian green alga bryopsis species

Kahalalide K (1), a new cyclic depsipeptide, was isolated from the Hawaiian green alga Bryopsis sp. Kahalalide K was determined to possess a new array of three L- and three D-amino acids, including a 3-hydroxy-9-methyldecanoic acid that had been previously reported in kahalalides E, H, and J.

Malyngamides M and N from the Hawaiian Red Alga Gracilaria coronopifolia

Two new malyngamides, M and N (1, 2), were isolated along with malyngamide I acetate (3) from the Hawaiian red alga Gracilaria coronopifolia. Our results suggest that malyngamide N (2) is a revised structure of deacetoxystylocheilamide (5). The absolute configuration of malyngamide I acetate was deduced to be 3 using the reversed octant rule.

A growth-hormone--producing pituitary adenoma and an internal carotid artery aneurysm.

The case of a growth-hormone-producing pituitary adenoma which was in direct contact with a right internal carotid, medial-type aneurysm is reported. Direct clipping of the aneurysm and subcapsular removal of the adenoma were performed through a right frontotemporal craniotomy. The rarity of this direct contact and the cause of formation and enlargement of the aneurysm are discussed. The importance of angiography in cases of pituitary adenoma is stressed.

Trigeminal pain caused by a parapontine epidermal cyst.

A case of trigeminal neuralgia caused by a parapontine epidermal cyst is reported. The trigeminal inlet zone at the pons was completely surrounded by the tumor. No vascular element was detected around the trigeminal nerve root. Neurological symptoms were completely normal except for typical tic douloureux. Pain was controlled initially by carbamazepine, later by radiofrequency trigeminal nerve coagulation, and finally by microsurgical decompression. Review of the literature suggested the importance of lesions of the middle fossa as another etiological factor. When surgery is performed by the posterior route, the possibility of overlooking these lesions may exist.