Asynchrony of Gambierdiscus spp. Abundance and Toxicity in the U.S. Virgin Islands: Implications for Monitoring and Management of Ciguatera

Ciguatera poisoning (CP) poses a significant threat to ecosystem services and fishery resources in coastal communities. The CP-causative ciguatoxins (CTXs) are produced by benthic dinoflagellates including Gambierdiscus and Fukuyoa spp., and enter reef food webs via grazing on macroalgal substrates. In this study, we report on a 3-year monthly time series in St. Thomas, US Virgin Islands where Gambierdiscus spp. abundance and Caribbean-CTX toxicity in benthic samples were compared to key environmental factors, including temperature, salinity, nutrients, benthic cover, and physical data. We found that peak Gambierdiscus abundance occurred in summer while CTX-specific toxicity peaked in cooler months (February–May) when the mean water temperatures were approximately 26–28 °C. These trends were most evident at deeper offshore sites where macroalgal cover was highest year-round. Other environmental parameters were not correlated with the CTX variability observed over time. The asynchrony between Gambierdiscus spp. abundance and toxicity reflects potential differences in toxin cell quotas among Gambierdiscus species with concomitant variability in their abundances throughout the year. These results have significant implications for monitoring and management of benthic harmful algal blooms and highlights potential seasonal and highly-localized pulses in reef toxin loads that may be transferred to higher trophic levels.     

注射用A型肉毒毒素联合眼袋整形术治疗眼周皮肤松弛的临床效果

目的 探讨注射用A型肉毒毒素联合眼袋整形术治疗眼周皮肤松弛的效果。方法 选择我院2020年 6月-2022年6月收治的1200例眼周皮肤松弛患者为研究对象,按照随机数字表法分为对照组与观察组, 各600例。对照组使用眼袋整形术治疗,观察组使用注射用A型肉毒毒素联合眼袋整形术治疗,比较两组 临床疗效、并发症发生情况、术后鱼尾纹、睑袋发生情况及满意度。结果 观察组皮肤色泽增强率、睑 袋减轻率、鱼尾纹改善率高于对照组（P＜0.05）;观察组并发症发生率低于对照组,但差异无统计学意 义（P＞0.05）;观察组动态、静态时睑袋及鱼尾纹发生率均低于对照组（P＜0.05）;观察组满意度高于对 照组（P＜0.05）。结论 在眼袋整形术治疗眼周皮肤松弛的基础上给予注射用A型肉毒毒素可进一步提高治 疗效果,促使皮肤色泽改善,预防鱼尾纹、睑袋发生,美学效果及患者满意度较高,值得临床应用。     

Involvement of metabotropic glutamate receptors in Gi- and Gs-dependent modulation of adenylate cyclase activity induced by a novel cognition enhancer NS-105 in rat brain

The effect of a novel cognition enhancer [(+)-5-oxo-

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-prolinepiperidinamide monohydrate] (NS-105) on cAMP formation was investigated in both slices and membranes of the rat cerebral cortex. NS-105 (10⁻⁸–10⁻⁶ M) inhibited forskolin-stimulated cAMP formation in membranes, however, the compound significantly enhanced the cAMP formation in pertussis toxin-pre-treated membranes, an action that was abolished by cholera toxin. In contrast, in digitonin-permeabilized membranes, NS-105 had no influence on Mn²⁺-stimulated cAMP formation. Both of the inhibitory and facilitatory actions of NS-105 on cAMP formation were mimicked by a metabotropic glutamate receptor (mGluR) agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD) and an adrenergic α₂ agonist UK-14,304, and blocked by a mGluR antagonist 2-amino-3-phosphonopropanoate but not by an α₂ antagonist yohimbine. In cortical slices, NS-105 (10⁻⁸–10⁻⁷ M) inhibited forskolin-stimulated cAMP accumulation but enhanced isoproterenol-stimulated cAMP accumulation, as did by a GABA_B agonist (−)baclofen. On the other hand, (−)baclofen, while it significantly inhibited cAMP accumulation in slices, did no longer inhibit cAMP accumulation, when treated with NS-105 (10⁻⁸–10⁻⁵ M). Similarly, (−)baclofen-induced inhibition of the cAMP accumulation was reversed by 1S,3R-ACPD and UK-14,304. NS-105 (10⁻⁶) increased [³⁵S]GTPγS binding in the intact but not digitonin-permeabilized cortical membranes, as produced by UK-14,304, although the compound (10⁻⁹–10⁻³ M) had no influence on various neurotransmitter receptor bindings, including α₂ receptors. These results suggest that NS-105 modulates adenylate cyclase activity by stimulating mGluRs which might coupled to both G_i/G_o and G_s. © 1997 Elsevier Science B.V. All rights reserved.     

Guidelines for the therapeutic use of botulinum toxin in movement disorders

Since its introduction in the early '80s the use of botulinum toxin has improved the quality of life of the patients affected by movement disorders. Toxin's neuromuscular blocking action allows a symptomatic treatment of those clinical conditions characterised by excessive muscular activity. Although the dosages used are safe and the side-effects are reversible, a correct use of botulinum toxin depends on the knowledge of its clinical pharmacology and of the anatomy of the body segments to be injected. In addition, the treatment of more complex conditions, i.e. laringeal dystonia, imposes an inter-disciplinary approach and specialised injection techniques.In this review, the Italian Study Group on Movement Disorders presents the consensus guidelines for the therapeutic use of botulinum toxin in movement disorders. The main toxin types, their use and administration modalities, and the training guidelines will be presented.

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Sommario Dalla sua introduzione nei primi anni '80, l'uso della tossina botulina ha prodotto un sensibile miglioramento della qualità della vita dei pazienti affetti da disordini del movimento. La sua azione bloccante la trasmissione neuromuscolare ha consentito il trattamento sintomatico di quelle condizioni cliniche caratterizzate da eccessiva attività muscolare. Nonostante la relativa sicurezza dei dosaggi impiegati e l'assenza di effetti collaterali irreversibili l'adeguato uso della tossina botulinica nei disordini del movimento dipende da conoscenze specifiche di farmacologia clinica e di anatomia normale funzionale dei distretti da infiltrare. Inoltre, per il trattamento di patologie più rare o complesse, come ad esempio la disfonia spasmodica, si rendono necessari un approccio interdisciplinare e speciali tecniche di somministrazione.In questo articolo vengono presentate le principali indicazioni alla terapia con tossina botulinica dei disordini del movimento redatte dal Gruppo di Studio per i Disordini del Movimento della S. I. N. Sono inoltre esposti i principali tipi di tossina disponibili sul mercato italiano, le modalità di uso e somministrazione nonché le nozioni di addestramento per il personale medico che intenda attuare tali terapie.

     

Gene therapy for human colorectal carcinoma using human CEA promoter contro led bacterial ADP-ribosylating toxin genes human CEA: PEA & DTA gene transfer

AIM:To establish a tissue-specific gene therapy for colorectal carcinoma using bacterial ADP-ribosylating toxin genes. METHODS:Pseudomonas exotoxin A domain [II+III (PEA) was cloned from genomic DNA of Pseudomonas aeruginosa.PEA and diphtheria toxin A chain gene (DTA) were modified to express eukaryotically. After sequencing, the toxin genes under the control of human carcinoembryonic antigen (CEA)promoter were cloned into retroviral vectors to construct CEAPEA and CEADTA respectively. In vitro cotransfection of the constructs with luciferase vectors and in vivo gene transfer in nude mice were subsequently carried out. RESULTS:Both CEAPEA and CEADTA specifically inhibited the reporter gene expression in the CEA positive human colorectal carcinoma (CRC) cells in vitro. Direct injection of CEAPEA and CEADTA constructs into the established human tumors in BALB/c nude mice led to significant and selective reductions in CRC tumor size as compared with that in control groups.CONCLUSION:The toxin genes, working as therapeutic genes, are suitable for the tissue-specific gene therapy for colorectal carcinoma.     

O148 Shiga toxin-producing Escherichia coli outbreak: microbiological investigation as a useful complement to epidemiological investigation

An outbreak of Shiga toxin-producing Escherichia coli (STEC) O148 infection occurred among wedding attendees in France in June 2002. A retrospective cohort study was performed and ten cases were identified, including two adults with haemolytic uraemic syndrome (HUS). The analytical study revealed that > 80% of affected individuals had eaten lightly roasted mutton and poultry paté, but only the consumption of paté tended to be associated with illness (relative risk 3.4; 95% CI 0.8-14.4). Left-overs (cooked mutton and raw offal) and processed foods (paté) from the same batches as served at the party were sampled. Human, food and environmental samples were examined for the Shiga toxin (stx) gene and virulence traits by PCR. Stx-positive samples were cultured for STEC. HUS cases were tested for serum antibodies against 26 major STEC serogroups. An STEC O26 strain (stx1, eae, ehxA) was isolated from one case with diarrhoea, and an STEC O148 strain (stx2c) from one case of HUS. Serum antibodies against O26 were not detected in either of these patients; antibodies against O148 were not tested. Three STEC strains were isolated from the mutton and the offal (stx2c, O148), and two from the paté (stx2c, O-X and O-Y). The isolates from the mutton were indistinguishable from the human stx2c isolate, whereas the paté isolates differed. Although four different STEC strains were identified in patients and foods, the results of molecular subtyping, in conjunction with analysis of food consumption patterns, strongly suggested that this outbreak was caused by mutton contaminated with STEC O148.     

Neutralization of enterotoxigenic escherichia coli heat‐labile toxin by chicken egg yolk immunoglobulin Y and its antigen‐binding fragments

The protective effect of chicken egg yolk immunoglobulin Y (IgY) and its antigen‐binding FAb’ fragments was studied by their neutralization of heat‐labile toxin (LT) produced by enterotoxigenic Escherichia coli (ETEC) strain H10407. High levels of specific antibodies against LT were produced and maintained over a period of 8 months in eggs of hyper‐immunized hens. The FAb’ fragment produced by peptic digestion was found to be as effective as the whole IgY molecule in neutralizing LT. Removal of the enterotoxin‐specific antibodies eliminated the neutralization activities of both IgY and the FAb’ fragment. Heat pasteurization at 65°C for 15 min and presence of high salt (1.5 M‐NaCl) at pH 7.0 did not change the neutralization activities of either IgY or FAb’. Although incubation at pH of 2.0 for 4 h led to a 16‐fold decrease in the neutralization activities of IgY and FAb’, substantial neutralization activities were retained. The combination of low pH and high salt content, however, resulted in the complete destruction of the neutralization activity of IgY, but not the FAb’ fragment.     

Functional state of the liver in experimental staphylococcal infection

In infection produced by intravenous injection of staphylococci of strain Wood-46 into albino rats, marked changes take place in the liver function and, in particular, the synthesis and liberation of bile acids are sharply inhibited. Their total concentration in the bile falls chiefly on account of taurocholic, glycocholic, and deoxycholic acids, whereas the concentration of cholic acid itself rises, evidently because of inhibition of the conversion of cholesterol into primary bile acids and conjugation of cholic acid with glycine and taurine. The hyperbilirubinocholia observed in the early periods of infection arises on account of hemolysis of the red cells.Department of Pharmacology, Khar'kov Pharmaceutical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. R. Pokrovskii.) Translated from Byulleten Éksperimental'noi Biologii i Meditsiny, Vol. 78, No. 11, pp. 49–51, November, 1974.     

一种新的编码霍乱毒素的丝状噬菌体CTAKΦ

目的 探讨介导霍乱弧菌毒素基因水平转移的一种独特的遗传结构。方法 从O139群霍乱弧菌菌株FJ97129上清中分离出丝状噬菌体颗粒CTAKΦ，并进行电镜观察。从丝状噬菌体颗粒CTAKΦ中纯化出DNA，并进行链型分析。对pCTAK进行酶谱分析。用ctxAB、zot引物对pCTAK进行PCR扩增检测，用RS1探针对pCTAK进行Southern blot检测；用pCTAK转化DH5α和IEM101得到DX29和4329，将pCTAK克隆于pUC18载体并转入DH5α得到UD29，用GM1－ELISA检测DX29、4329、UD29的CT表达。对pCTAK的ctxAB、zot基因片段进行测序，并用DNASTAR软件和BLAST算法，在国际互联网上对测序结果进行序列分析。结果 发现和分离了一种编码霍乱毒素的质粒pCTAK，它以稳定的高拷贝数存在于1株天然的O139霍乱弧菌FJ97129中；酶谱分析发现其明显不同于CTX元件酶谱，在CTX元件中相当保守的酶切位点：BglⅡ、EcoRⅤ、PstⅠ、EcoRⅠ，在pCTAK中没有切点。ctxAB、zot引物对pCTAK的PCR扩增检测呈阳性，RS1探针杂交呈阳性；pCTAK的ctxAB、zot基因序列与已报道的序列有很高的同源性。pCTAK能直接或经载体转化DH5α和IEM101并表达CT。从FJ97129培养上清中分离出丝状噬菌体颗粒CTAKΦ，电镜观察并计算其直径大小为7nm左右。其全基因组大小为8.5kb，为单链DNA。结论 发现了一种新的编码霍乱毒素的丝状噬菌体CTAKΦ。     

幽门螺杆菌全长cagA基因和霍乱毒素B亚单位基因的克隆与表达

目的：构建表达幽门螺杆菌（Hp)细胞毒素相关蛋白（CagA)及粘膜免疫佐剂量霍乱毒素B亚单位（CTB）的重组质粒，并在大肠杆菌中表达获得基因重组蛋白。方法：用PCR方法从幽门螺杆菌扩增CagA基因片段，从霍乱弧菌扩增CTB基因片段，将它们转入原核载体质粒pGEMEX-1，在大肠杆菌DH5α中克隆，并在JM109DE3中表达。结果：重组质粒pEGEMEX-CTB的全长序列经分析与GenBank公布的序列相符；各表达蛋白经SDS－PAGE分析，相对分子量与文献相符；重组蛋白经Westem blot检测有较强的抗原性。结论：基因重组菌表达的融合蛋白有可能作为有效抗原用于幽门螺杆菌疫苗的研制及检测试剂盒的制备。