Zenodo (CERN European Organization for Nuclear Research), Jun 27, 1994
This event assembled 273 registered participants and some occasional visitors, in all about 300 p... more This event assembled 273 registered participants and some occasional visitors, in all about 300 persons from more than 40 countries, during five days of plenary sessions and round table discussions. Four scientific themes were explored: the mechanisms of harmful bloom formation, identification and dete&"on of responsible species, cellular biochemistry and physiology, and bioaccumulation effects of phycotoxins. These themes were treated in oral communications and 160 posters, while round table discussions were devoted to subjects previously given less consideration, such as toxic Cyanobacteria blooms and the ecology of benthic dinoflagellates.
Zenodo (CERN European Organization for Nuclear Research), Jun 15, 1996
Payment in US$ (30), French Francs (155), or Danish Kroner (175) as cash or cheque, payable to H.... more Payment in US$ (30), French Francs (155), or Danish Kroner (175) as cash or cheque, payable to H. Enevoldsen, IOC. Scientists and libraries in developing countries can request provision free of charge.
Zenodo (CERN European Organization for Nuclear Research), Nov 27, 1994
An investigation into the agent responsible for food poisoning events associated with eating seaf... more An investigation into the agent responsible for food poisoning events associated with eating seafood has led to the incrimination of molluscs collected on the Mediterranean shoreline of Morocco. Their gathering and sale are now banned. The study was carried out on two species currently consumed in the region: the cockle, Cardium tuberculatum , and the hard-shell clam, Cuterce chrome. These species were sampled at regular intervals over a year, from May 1993 to May 1994, in the region of Tetouan at Kaa Stras and Oued Laou, in order to assess the toxicity of the bivalves there. Extracts of the molluscs were prepared according to the official method (Association of Official and Analytical Chemists, 1980). The toxicity of the extracts was assayed on Swiss Albjno mice, Cardium tuberculatum gave the highest toxicities at Kaa Stras, but in both cases toxicity levels remained high throughout the year and produced rapid death, preceded by PSP-type symptoms, while Cuterce chrome gave lower levels, whatever the period of collection. Cardium tuberculatum: Kaa Stras, toxicity 1207 Mouse Units (MU)/100g of meat. Oued Laou, 773 MU/100g Cuterce chrome: 190 MUI100g Comparative investigation of the toxicity in different organs of the cockles showed that toxicity levels were clearly higher in the foot (5580 MU/100g) than in the mantle (1030 MIUl100g). The investigation carried out has shown that biotoxin presence is permanent in cockles in the region of Tetouan, but varies over the year.
Zenodo (CERN European Organization for Nuclear Research), Dec 15, 1993
An IOC Newsletter on toxic algae and algal blooms No. 7 cohorticula, A. findyense, A. fiaterculus... more An IOC Newsletter on toxic algae and algal blooms No. 7 cohorticula, A. findyense, A. fiaterculus, A. minutum, Gymnodinium catenatum, Pyrodinium bahamense var compressum and Prorocentrum minimum, but not by other species of Alexandrium, Gymnodinium and Pyrodinium. Silva (Proc. IV IUPAC Symp. on Mycotoxins and Phycotoxins, Lausanne. Proc. Pathotox Publ. 1979) suggested that dinoflagellate toxin production may be due to bacteria living in association with the dinoflagellate. Recently Kodama & Ogata (Mar. Poll. Bull. 19, 559-564, 1988) also pointed out the possible association of bacteria in cell interiors with toxin production by A. tamarense, and suggested that toxin production is not a hereditary characteristic of A. tamarense. We thought that this hypothesis has not as yet been supported with sufficient evidence, given that (1) the algal cultures were not axenic, and (2) there were only a few bacteria in the nuclei of 10-15% of the many algal cells present. However, we cannot deny the possible association of factors other than bacteria, such as (Cont'd on p. 3) (Cont'd on p. 4)
Zenodo (CERN European Organization for Nuclear Research), Nov 27, 1995
An IOC Newsletter on toxic algae and algal blooms No. 12/13 Florida red tides Gymnodinium breve c... more An IOC Newsletter on toxic algae and algal blooms No. 12/13 Florida red tides Gymnodinium breve cell counts near West Palm Beach, Florida (26.55 N, 80.00 W) and the position of the western edge of the Gulf Stream. Note on an unknown poison HAN issue N° 5 (page 1) carried an account of a toxic event of unknown aetiology in French coastal waters, which lasted from November 1992 until May 1993. No toxic organism had been identified at the time, although the mouse test suggested the presence of PSP. But the toxin was unstable, and chemical analysis failed to detect it. Further details have been made available by Françoise Marco (1) of the Laboratoire côtier in Toulon. Mussels from Toulon screened by J. Minet of the Faculté de P harmacie, Rennes, revealed a flora dominated by Bacillus cereus. Other common pathogens (Salmonella, Staphylococcus, Clostridium) were absent. Acetone extracts of a pure strain of B. cereus injected into mice provoked the same symptoms as mussel extracts.
Zenodo (CERN European Organization for Nuclear Research), Feb 27, 1996
An IOC Newsletter on toxic algae and algal blooms No. 14 In November 1995, a bloom of Pyrodinium ... more An IOC Newsletter on toxic algae and algal blooms No. 14 In November 1995, a bloom of Pyrodinium bahamense var. compressum was recorded off Acapulco in the state of Guerrero, Mexico. It subsequently moved southeast along the Mexican and Guatemalan coasts in the early days of December. Toxin levels estimated by bioassay reached levels of 8,549 µg/100 g-1 in oyster (ostión) meat, and measures to protect public health were taken. The saxitoxin was identified by HPLC and compared with the results of the bioassay using the same extracts. This bloom was not completely unexpected, since high concentrations of the same species (up to 1.7 x 10 6 cells l-1) occurred in November 1989 in the same region, (1) and off the coast of G u atemala in summer 1987. (2) Th e toxin levels in the recent episode were an order of magnitude higher than in 1989 (811 µg/100 g-1 of meat) using the same method and it is therefore recommended that the region be monitored in a responsible and continuous way. A new outbreak in the area was reported in the second half of February 1996. E l i z abeth Ore l l a n a-C epeda, Unive rs idad Autónoma de Baja Califo rnia, Mex i c o. Pyrodinium toxicity reappears near Acapulco See also article on page 4 for more news on Mexico. After almost four years of preparation, a c o m p re h e n s ive M a nual on Harm f u l Marine Microalgae has been published in the IOC Manual and Guides series as volume No. 33. The 500-page manual includes chapters on taxonomy, field techniques, culturing techniques, algal toxin ch e m i s t ry, detection and quantific ation, as well as description of monitoring and management practices. The manual is edited by Drs. G. Hallegaeff, University of Tasmania (Au s t ra l i a) , D. A n d e rson, Woods Hole O c e a n ographic Institution (USA), and A. Cembella,
Zenodo (CERN European Organization for Nuclear Research), Jun 27, 1995
In 1994 high concentrations of algae were found in water samples off the Dutch Coast, on the Noor... more In 1994 high concentrations of algae were found in water samples off the Dutch Coast, on the Noordwijk transect. The seasonal sequence started with a bloom of Phaeocystis sp. in April. In June we observed Pseudonitzchia pungens forma pungens (Grunow in Cleve & Miiller) Hasle with 380.103 cells/l. Fi n ~u l~ a Dinophysis acuminata bloom of long duration with maximum concentrations of 8.103 cell11 started. In the coloured water masses during August 1994, the Raphidophycean species Heterosigma akashiwo was found, a new species for Dutch coastal waters. The water column was slightly stratified (see table below). In an extra sample, taken from Station 1 (from the pink water), large numbers of small svecies. like Kato-shown at a phytoplankton workshop held in Biisum, Germany, 2-3 March 1995. At that meeting, Dr. Malte Elbrachter from the List Biological Station showed cultures of Heterosigma akashiwo. Good agreement was found between the cultured material and the video taped field material. The material from Dr. Elbrachter as well as the material from the Dutch Coast could not be preserved with Lug01 or Formalin: after preservation no identification could be made; the cells changed into a cluster of small unrecognizable particles. Heterosigma akashiwo was reported by Dr. Elbrachter on 26 August and 15 December 1994, at sampling station Weststrand off List and Wadden Sea 1, respectively, in the German Waddensee. dinium rotundatum, solitary Chaeto-1) FU~UYO, Y. et al. (eds.), 1991. Red tide organisms in Japan. An illustrated taxonomic guide. ceros cells and flagellates were ob-Uchida Rokakuho, Tokyo, 407 DV. served. In this last group we identified 2) Larsen, J. and ~o e s & u~, g.,-f989. Guide to-A the ~~~h i d~~h~~~~~ ~~t~~~~i~ aka-toxic and potentially toxiE marine algae. Fish Inspection Service, Ministry of Fisheries, shiwo with the following details: two Copenhagen, 61 pp. flagellae, width = 20 wm, length = 1 5 i m (with some size variation), numerous yellow/brown chromatophores, more or less flat in side view. The characteristic rotating movement was recorded on video. The total numbers per litre were 2.4 X 106. This species is known to be toxic to fish('s2), but no dead fish were observed. The video tapes with Heterosigma akashiwo from the Dutch Coast were
Zenodo (CERN European Organization for Nuclear Research), Sep 13, 1993
HARMFUL ALGAE NEWS An IOC Newsletter on toxic algae and algal blooms No. 6 tional wisdom that onl... more HARMFUL ALGAE NEWS An IOC Newsletter on toxic algae and algal blooms No. 6 tional wisdom that only phytoflagellates (excepting cyanobacteria) In. 1987 an U~U S U~~ series of human were phycotoxin producers, it illnesses and deaths was detcrmined to came as a surprise to me that the be caused by consumption of mussel.; capacity to synthesize potent contaminated by domoic acid (DA) '. mammalian toxins is shared with This potent ncurotoxin, produced by the diatoms. Under-flagellatedthus PCnnate diatom ~.~~l l h l l i t~.~~' / l i~ (forcomparatively boring t~ watch lnerly Nitzscliitr) plIflgen5 f. mlrltiunder the microscope (Victorian .Wries'", Was found during late autumdiatom gardens notwithstanding), " " 1 blooms in estuaries of eastem Prince and of limited apparent use other Edward Island (PEI), in Atlantic than in such utilitarian products Canada. The chronology of thcsc as polishing compounds, diatoms ~V C I I~S ' ' and many other aSpCctS of these always seemed to lack a certain phenomena have bcen reviewed rc-'je ne sais quoi' compared to fla-cent1~'4. gellates. Yes, as first among Prior to 1987, it was believed thar equals at the base of marine food PE1 and nearby regions of the Gulf of chains, diatoms are certainly im-Sr. Lawrence were free from h;umful portant, but roughage for "gal problems and no ~rgular monitorcopepods is hardly a sexy role. ing program for phycotoxin-producing Frankly, I'm a bit disappointed to phytoplankton Was in place. Following admit diatoms into the first ranks the tr"iC events of 1987. projects Were of marine 'killer' organisms! Per-undertaken to determine the spatial and baps Pseudonitzschia really pro-temporal patterns of abundance of P. duce pseudo-domoic acid. prii~gens and occun-ences of DA toxicity On a more serious note, the in phyloplanklon and shellfish. A further recent National Shellfisheries AS-;lim Was to acquire a prcdictivc capabisociation Annual Meeting in port-lity by relating the physical, chemical, land, Oregon, USA (31 May-biological and hydrographic parameters 3 June, 1993) hosted a special g~verning the timing and intensity of mini-symposium, sponsored by lhesc SEAGRANT, on 'Harmful Phyto-Large scalc meteorological events plankton and Shellfish Interac-appear to be imponant in determining tions9. was noteworthy that the the magnitude of I ? prriige1l.s blooms.
Zenodo (CERN European Organization for Nuclear Research), Nov 16, 1992
For 30 years the search has gone on for fenses, inadequacies in sanitation, an environmental rese... more For 30 years the search has gone on for fenses, inadequacies in sanitation, an environmental reservoir for cholera clean water, and fuel supply, as well as to help explain seasonal oscillations. the uncontrolled urbanization (eg, Dr Ventura and colleagues(l) demon-Lima's shantytowns) generated by the strate that the growth of Vibrio chole-economic collapse of the 1980s.. rue non-01 on plant,samples in sew-There is now convincing evidence age lagoons is assodated with the sea-for an environmental reservoir for sonality of cholera in Peru. Colwell and cholera. Alterations, due to climatic her colleagues(2) have also detected V. change, in the distribution of watercholerae 0 1 on marine life, in non-based and vector-borne diseases have culturable, viable states, and have de-been predicted(10n11), and the pattern of monstrated that this reservoir is semi-cholera in the Americas may represent tive to environmental changes. the first detectable impact. Of the Under unfavourable conditions, greenhouse gases, carbon emissions cholera bacteria become dormant, reconstitute 50%; and an international emerging to an infectious state with treaty to limit worldwide release was warming and nutrient availability. on the agenda for the UN Conference 'Hibernating' forms of V. chderae m-on the Environment and Development exist with a wide variety of algae and in Rio de Janeiro in June 1992. The planl~ton(~X~), which are also respon-changing distribution of old diseases sive to changes in temperature, pH, (and the emergence of new ones) salinity, and nutrition. Climatologists makes it essential that public health repoa unusually large algae and plank-professiods and scientists participate ton blooms at sea, and plankton centrally in planning developments. sampled in the harbour near Lima, Peru, are contaminated with V. cho-By Paul R. Epstein, Cambridge Hospil e r~e '~). tal, Harvard Medical School, Cam-Phytoplankton and algae help bridge, Massachussetts 02139, USA. modulate our climate(@. They absorb atmospheric carbon (2 of the 7 billion metric tons released annually) and give (l) Ventura, G. et al.
In a conceptual model proposed before, the onset of the upwelling season and availability of Meso... more In a conceptual model proposed before, the onset of the upwelling season and availability of Mesodinium rubrum prey are essential conditions for the initiation of Dinophysis acuminata blooms in the Galician Rías Baixas (NW Spain). Distribution of sexual cysts from the previous year in the top sediment layer is an important parameter in forecasting models of cyst-forming species (e.g. Alexandrium spp.). But the existence of sexual cysts of Dinophysis spp. has not been confirmed, Dinophysis planozygotes can divide and produce vegetative cells directly, and it is possible that species of this genus do not rely on sexual cysts but on some kind of overwintering planktonic form as a seeding mechanism. Here we examine winter conditionspersistence or absence of overwintering cells of Dinophysis within the rías and the adjacent shelf and time of initiation of the upwelling season-from observations in the last 20 years. Our ultimate goal was to explain the abundance and early initiation in April 2012 of an extraordinary bloom of D. acuminata, in what appeared to be a mesoscale event affecting other regions in Western Europe. The dynamics of D. acuminata populations appeared tightly coupled to the upwelling season. Our results suggest that anomalous upwelling patterns (predominance of upwelling in winter) combined with the presence of overwintering (inoculum) cells lead to early initiation of the Dinophysis acuminata growth season.
Dinophysis acuminata and Dinophysis acuta produce lipophilic toxins that cause most shellfish har... more Dinophysis acuminata and Dinophysis acuta produce lipophilic toxins that cause most shellfish harvesting closures in the Atlantic coastal waters of Europe. Dinophysis often exhibit patchy distributions and sampling with conventional methods may fail to detect them. A 6-month calibration study in 2006, plus an additional sampling in 2010 were carried out in Galicia to compare Dinophysis counts obtained from weekly high vertical resolution bottle samples with depth-integrated hose samples. Counts with these two methods were comparable at some depth-ranges, but hose maxima were over one order of magnitude lower under thin-layer scenarios. Estimates from hose samplers should be used with caution in programmes using a "Dinophysis index", either to trigger shellfish sampling or to establish precautionary harvesting closures. In general, hose samplers provide reliable information on the occurrence of Dinophysis except under extreme site-specific hydrodynamic conditions. This study adds new information about the heterogeneous, specific vertical distributions of two Dinophysis spp.
... pH values to be corrected to a temperature of 15°C. Oxygen was measured by the Winkler method... more ... pH values to be corrected to a temperature of 15°C. Oxygen was measured by the Winkler method. ... Chaetoceros didymus Ehrenbcrg Medium-sized oligotnehous ciliates Leptocylindrus danicusCleve Nitzschia senata Cleve Small oligotnehous ciliates RhizosoUma fragihssuna ...
Blooms of Dinophysis spp. associated with lipophilic shellfish toxin outbreaks are common in Nort... more Blooms of Dinophysis spp. associated with lipophilic shellfish toxin outbreaks are common in Northwestern Iberia waters from spring to autumn. Blooms of Dinophysis acuta are very seasonal (late summer-early autumn); they start earlier in Northern Portuguese waters during the upwelling season, and reach their maximum values in the Galician Rías during downwelling events at the end of the upwelling season. There is controversy about whether sudden increases in cell concentrations in the rías result from cross-shelf transport of populations previously established in adjacent shelf waters, or are due to longshore transport that brings populations located off Portugal to the North. In 2005, record concentrations of D. acuta were observed in Portuguese waters (14 Â 10 4 cell L À1) off Aveiro in early September, while concentrations off the Galician coast were very moderate (10 2-10 3 cell L À1). During the autumn transition from upwelling-to downwelling-favourable winds, D. acuta declined abruptly off Portugal while the annual maximum (up to 22 Â 10 3 cell L À1) was found in the Galician Rías. A new approach was used that combined physical observations (SST, current measurements); weekly observations from monitoring programmes in Galicia and Portugal; weekly division rate (m min) estimates of D. acuta in Ría de Vigo, together with monthly transects and additional ad hoc sampling in the Ría. During August and early September, division rates were high in Ría de Vigo but concentrations were low, whereas higher SST values in Portugal (a proxy for thermal stratification) seemed to promote the build up of high densities of D. acuta. During the last week of October and the first week of November, populations declined, whereas in Galicia, maximum concentrations were reached while division rate estimates were almost zero. Results presented here confirm that increased numbers in the Galician Rías are not due to intrinsic growth but to physically driven accumulation; a simple cell concentration budget calculated during the accumulation period suggests that the high net growth observed during downwelling, in the absence of cellular division, must be due to cells imported by longshore transport.
... a CCMM, Conselleria de Pesca, Peirao de Vilaxoán s/n, Vilagarcía de Arousa, Pontevedra, Spain... more ... a CCMM, Conselleria de Pesca, Peirao de Vilaxoán s/n, Vilagarcía de Arousa, Pontevedra, Spain. b Instituto Español de Oceanografía, Cabo Estay, Vigo, Pontevedra, Spain. ... View Within Article. 3.2. Distribution of DAHs and DDPAHs in the Ria de Vigo. ...
Background In past number of methods have been developed for predicting subcellular location of e... more Background In past number of methods have been developed for predicting subcellular location of eukaryotic, prokaryotic (Gram-negative and Gram-positive bacteria) and human proteins but no method has been developed for mycobacterial proteins which may represent repertoire of potent immunogens of this dreaded pathogen. In this study, attempt has been made to develop method for predicting subcellular location of mycobacterial proteins. Results The models were trained and tested on 852 mycobacterial proteins and evaluated using five-fold cross-validation technique. First SVM (Support Vector Machine) model was developed using amino acid composition and overall accuracy of 82.51% was achieved with average accuracy (mean of class-wise accuracy) of 68.47%. In order to utilize evolutionary information, a SVM model was developed using PSSM (Position-Specific Scoring Matrix) profiles obtained from PSI-BLAST (Position-Specific Iterated BLAST) and overall accuracy achieved was of 86.62% with av...
Zenodo (CERN European Organization for Nuclear Research), Jun 27, 1994
This event assembled 273 registered participants and some occasional visitors, in all about 300 p... more This event assembled 273 registered participants and some occasional visitors, in all about 300 persons from more than 40 countries, during five days of plenary sessions and round table discussions. Four scientific themes were explored: the mechanisms of harmful bloom formation, identification and dete&"on of responsible species, cellular biochemistry and physiology, and bioaccumulation effects of phycotoxins. These themes were treated in oral communications and 160 posters, while round table discussions were devoted to subjects previously given less consideration, such as toxic Cyanobacteria blooms and the ecology of benthic dinoflagellates.
Zenodo (CERN European Organization for Nuclear Research), Jun 15, 1996
Payment in US$ (30), French Francs (155), or Danish Kroner (175) as cash or cheque, payable to H.... more Payment in US$ (30), French Francs (155), or Danish Kroner (175) as cash or cheque, payable to H. Enevoldsen, IOC. Scientists and libraries in developing countries can request provision free of charge.
Zenodo (CERN European Organization for Nuclear Research), Nov 27, 1994
An investigation into the agent responsible for food poisoning events associated with eating seaf... more An investigation into the agent responsible for food poisoning events associated with eating seafood has led to the incrimination of molluscs collected on the Mediterranean shoreline of Morocco. Their gathering and sale are now banned. The study was carried out on two species currently consumed in the region: the cockle, Cardium tuberculatum , and the hard-shell clam, Cuterce chrome. These species were sampled at regular intervals over a year, from May 1993 to May 1994, in the region of Tetouan at Kaa Stras and Oued Laou, in order to assess the toxicity of the bivalves there. Extracts of the molluscs were prepared according to the official method (Association of Official and Analytical Chemists, 1980). The toxicity of the extracts was assayed on Swiss Albjno mice, Cardium tuberculatum gave the highest toxicities at Kaa Stras, but in both cases toxicity levels remained high throughout the year and produced rapid death, preceded by PSP-type symptoms, while Cuterce chrome gave lower levels, whatever the period of collection. Cardium tuberculatum: Kaa Stras, toxicity 1207 Mouse Units (MU)/100g of meat. Oued Laou, 773 MU/100g Cuterce chrome: 190 MUI100g Comparative investigation of the toxicity in different organs of the cockles showed that toxicity levels were clearly higher in the foot (5580 MU/100g) than in the mantle (1030 MIUl100g). The investigation carried out has shown that biotoxin presence is permanent in cockles in the region of Tetouan, but varies over the year.
Zenodo (CERN European Organization for Nuclear Research), Dec 15, 1993
An IOC Newsletter on toxic algae and algal blooms No. 7 cohorticula, A. findyense, A. fiaterculus... more An IOC Newsletter on toxic algae and algal blooms No. 7 cohorticula, A. findyense, A. fiaterculus, A. minutum, Gymnodinium catenatum, Pyrodinium bahamense var compressum and Prorocentrum minimum, but not by other species of Alexandrium, Gymnodinium and Pyrodinium. Silva (Proc. IV IUPAC Symp. on Mycotoxins and Phycotoxins, Lausanne. Proc. Pathotox Publ. 1979) suggested that dinoflagellate toxin production may be due to bacteria living in association with the dinoflagellate. Recently Kodama & Ogata (Mar. Poll. Bull. 19, 559-564, 1988) also pointed out the possible association of bacteria in cell interiors with toxin production by A. tamarense, and suggested that toxin production is not a hereditary characteristic of A. tamarense. We thought that this hypothesis has not as yet been supported with sufficient evidence, given that (1) the algal cultures were not axenic, and (2) there were only a few bacteria in the nuclei of 10-15% of the many algal cells present. However, we cannot deny the possible association of factors other than bacteria, such as (Cont'd on p. 3) (Cont'd on p. 4)
Zenodo (CERN European Organization for Nuclear Research), Nov 27, 1995
An IOC Newsletter on toxic algae and algal blooms No. 12/13 Florida red tides Gymnodinium breve c... more An IOC Newsletter on toxic algae and algal blooms No. 12/13 Florida red tides Gymnodinium breve cell counts near West Palm Beach, Florida (26.55 N, 80.00 W) and the position of the western edge of the Gulf Stream. Note on an unknown poison HAN issue N° 5 (page 1) carried an account of a toxic event of unknown aetiology in French coastal waters, which lasted from November 1992 until May 1993. No toxic organism had been identified at the time, although the mouse test suggested the presence of PSP. But the toxin was unstable, and chemical analysis failed to detect it. Further details have been made available by Françoise Marco (1) of the Laboratoire côtier in Toulon. Mussels from Toulon screened by J. Minet of the Faculté de P harmacie, Rennes, revealed a flora dominated by Bacillus cereus. Other common pathogens (Salmonella, Staphylococcus, Clostridium) were absent. Acetone extracts of a pure strain of B. cereus injected into mice provoked the same symptoms as mussel extracts.
Zenodo (CERN European Organization for Nuclear Research), Feb 27, 1996
An IOC Newsletter on toxic algae and algal blooms No. 14 In November 1995, a bloom of Pyrodinium ... more An IOC Newsletter on toxic algae and algal blooms No. 14 In November 1995, a bloom of Pyrodinium bahamense var. compressum was recorded off Acapulco in the state of Guerrero, Mexico. It subsequently moved southeast along the Mexican and Guatemalan coasts in the early days of December. Toxin levels estimated by bioassay reached levels of 8,549 µg/100 g-1 in oyster (ostión) meat, and measures to protect public health were taken. The saxitoxin was identified by HPLC and compared with the results of the bioassay using the same extracts. This bloom was not completely unexpected, since high concentrations of the same species (up to 1.7 x 10 6 cells l-1) occurred in November 1989 in the same region, (1) and off the coast of G u atemala in summer 1987. (2) Th e toxin levels in the recent episode were an order of magnitude higher than in 1989 (811 µg/100 g-1 of meat) using the same method and it is therefore recommended that the region be monitored in a responsible and continuous way. A new outbreak in the area was reported in the second half of February 1996. E l i z abeth Ore l l a n a-C epeda, Unive rs idad Autónoma de Baja Califo rnia, Mex i c o. Pyrodinium toxicity reappears near Acapulco See also article on page 4 for more news on Mexico. After almost four years of preparation, a c o m p re h e n s ive M a nual on Harm f u l Marine Microalgae has been published in the IOC Manual and Guides series as volume No. 33. The 500-page manual includes chapters on taxonomy, field techniques, culturing techniques, algal toxin ch e m i s t ry, detection and quantific ation, as well as description of monitoring and management practices. The manual is edited by Drs. G. Hallegaeff, University of Tasmania (Au s t ra l i a) , D. A n d e rson, Woods Hole O c e a n ographic Institution (USA), and A. Cembella,
Zenodo (CERN European Organization for Nuclear Research), Jun 27, 1995
In 1994 high concentrations of algae were found in water samples off the Dutch Coast, on the Noor... more In 1994 high concentrations of algae were found in water samples off the Dutch Coast, on the Noordwijk transect. The seasonal sequence started with a bloom of Phaeocystis sp. in April. In June we observed Pseudonitzchia pungens forma pungens (Grunow in Cleve & Miiller) Hasle with 380.103 cells/l. Fi n ~u l~ a Dinophysis acuminata bloom of long duration with maximum concentrations of 8.103 cell11 started. In the coloured water masses during August 1994, the Raphidophycean species Heterosigma akashiwo was found, a new species for Dutch coastal waters. The water column was slightly stratified (see table below). In an extra sample, taken from Station 1 (from the pink water), large numbers of small svecies. like Kato-shown at a phytoplankton workshop held in Biisum, Germany, 2-3 March 1995. At that meeting, Dr. Malte Elbrachter from the List Biological Station showed cultures of Heterosigma akashiwo. Good agreement was found between the cultured material and the video taped field material. The material from Dr. Elbrachter as well as the material from the Dutch Coast could not be preserved with Lug01 or Formalin: after preservation no identification could be made; the cells changed into a cluster of small unrecognizable particles. Heterosigma akashiwo was reported by Dr. Elbrachter on 26 August and 15 December 1994, at sampling station Weststrand off List and Wadden Sea 1, respectively, in the German Waddensee. dinium rotundatum, solitary Chaeto-1) FU~UYO, Y. et al. (eds.), 1991. Red tide organisms in Japan. An illustrated taxonomic guide. ceros cells and flagellates were ob-Uchida Rokakuho, Tokyo, 407 DV. served. In this last group we identified 2) Larsen, J. and ~o e s & u~, g.,-f989. Guide to-A the ~~~h i d~~h~~~~~ ~~t~~~~i~ aka-toxic and potentially toxiE marine algae. Fish Inspection Service, Ministry of Fisheries, shiwo with the following details: two Copenhagen, 61 pp. flagellae, width = 20 wm, length = 1 5 i m (with some size variation), numerous yellow/brown chromatophores, more or less flat in side view. The characteristic rotating movement was recorded on video. The total numbers per litre were 2.4 X 106. This species is known to be toxic to fish('s2), but no dead fish were observed. The video tapes with Heterosigma akashiwo from the Dutch Coast were
Zenodo (CERN European Organization for Nuclear Research), Sep 13, 1993
HARMFUL ALGAE NEWS An IOC Newsletter on toxic algae and algal blooms No. 6 tional wisdom that onl... more HARMFUL ALGAE NEWS An IOC Newsletter on toxic algae and algal blooms No. 6 tional wisdom that only phytoflagellates (excepting cyanobacteria) In. 1987 an U~U S U~~ series of human were phycotoxin producers, it illnesses and deaths was detcrmined to came as a surprise to me that the be caused by consumption of mussel.; capacity to synthesize potent contaminated by domoic acid (DA) '. mammalian toxins is shared with This potent ncurotoxin, produced by the diatoms. Under-flagellatedthus PCnnate diatom ~.~~l l h l l i t~.~~' / l i~ (forcomparatively boring t~ watch lnerly Nitzscliitr) plIflgen5 f. mlrltiunder the microscope (Victorian .Wries'", Was found during late autumdiatom gardens notwithstanding), " " 1 blooms in estuaries of eastem Prince and of limited apparent use other Edward Island (PEI), in Atlantic than in such utilitarian products Canada. The chronology of thcsc as polishing compounds, diatoms ~V C I I~S ' ' and many other aSpCctS of these always seemed to lack a certain phenomena have bcen reviewed rc-'je ne sais quoi' compared to fla-cent1~'4. gellates. Yes, as first among Prior to 1987, it was believed thar equals at the base of marine food PE1 and nearby regions of the Gulf of chains, diatoms are certainly im-Sr. Lawrence were free from h;umful portant, but roughage for "gal problems and no ~rgular monitorcopepods is hardly a sexy role. ing program for phycotoxin-producing Frankly, I'm a bit disappointed to phytoplankton Was in place. Following admit diatoms into the first ranks the tr"iC events of 1987. projects Were of marine 'killer' organisms! Per-undertaken to determine the spatial and baps Pseudonitzschia really pro-temporal patterns of abundance of P. duce pseudo-domoic acid. prii~gens and occun-ences of DA toxicity On a more serious note, the in phyloplanklon and shellfish. A further recent National Shellfisheries AS-;lim Was to acquire a prcdictivc capabisociation Annual Meeting in port-lity by relating the physical, chemical, land, Oregon, USA (31 May-biological and hydrographic parameters 3 June, 1993) hosted a special g~verning the timing and intensity of mini-symposium, sponsored by lhesc SEAGRANT, on 'Harmful Phyto-Large scalc meteorological events plankton and Shellfish Interac-appear to be imponant in determining tions9. was noteworthy that the the magnitude of I ? prriige1l.s blooms.
Zenodo (CERN European Organization for Nuclear Research), Nov 16, 1992
For 30 years the search has gone on for fenses, inadequacies in sanitation, an environmental rese... more For 30 years the search has gone on for fenses, inadequacies in sanitation, an environmental reservoir for cholera clean water, and fuel supply, as well as to help explain seasonal oscillations. the uncontrolled urbanization (eg, Dr Ventura and colleagues(l) demon-Lima's shantytowns) generated by the strate that the growth of Vibrio chole-economic collapse of the 1980s.. rue non-01 on plant,samples in sew-There is now convincing evidence age lagoons is assodated with the sea-for an environmental reservoir for sonality of cholera in Peru. Colwell and cholera. Alterations, due to climatic her colleagues(2) have also detected V. change, in the distribution of watercholerae 0 1 on marine life, in non-based and vector-borne diseases have culturable, viable states, and have de-been predicted(10n11), and the pattern of monstrated that this reservoir is semi-cholera in the Americas may represent tive to environmental changes. the first detectable impact. Of the Under unfavourable conditions, greenhouse gases, carbon emissions cholera bacteria become dormant, reconstitute 50%; and an international emerging to an infectious state with treaty to limit worldwide release was warming and nutrient availability. on the agenda for the UN Conference 'Hibernating' forms of V. chderae m-on the Environment and Development exist with a wide variety of algae and in Rio de Janeiro in June 1992. The planl~ton(~X~), which are also respon-changing distribution of old diseases sive to changes in temperature, pH, (and the emergence of new ones) salinity, and nutrition. Climatologists makes it essential that public health repoa unusually large algae and plank-professiods and scientists participate ton blooms at sea, and plankton centrally in planning developments. sampled in the harbour near Lima, Peru, are contaminated with V. cho-By Paul R. Epstein, Cambridge Hospil e r~e '~). tal, Harvard Medical School, Cam-Phytoplankton and algae help bridge, Massachussetts 02139, USA. modulate our climate(@. They absorb atmospheric carbon (2 of the 7 billion metric tons released annually) and give (l) Ventura, G. et al.
In a conceptual model proposed before, the onset of the upwelling season and availability of Meso... more In a conceptual model proposed before, the onset of the upwelling season and availability of Mesodinium rubrum prey are essential conditions for the initiation of Dinophysis acuminata blooms in the Galician Rías Baixas (NW Spain). Distribution of sexual cysts from the previous year in the top sediment layer is an important parameter in forecasting models of cyst-forming species (e.g. Alexandrium spp.). But the existence of sexual cysts of Dinophysis spp. has not been confirmed, Dinophysis planozygotes can divide and produce vegetative cells directly, and it is possible that species of this genus do not rely on sexual cysts but on some kind of overwintering planktonic form as a seeding mechanism. Here we examine winter conditionspersistence or absence of overwintering cells of Dinophysis within the rías and the adjacent shelf and time of initiation of the upwelling season-from observations in the last 20 years. Our ultimate goal was to explain the abundance and early initiation in April 2012 of an extraordinary bloom of D. acuminata, in what appeared to be a mesoscale event affecting other regions in Western Europe. The dynamics of D. acuminata populations appeared tightly coupled to the upwelling season. Our results suggest that anomalous upwelling patterns (predominance of upwelling in winter) combined with the presence of overwintering (inoculum) cells lead to early initiation of the Dinophysis acuminata growth season.
Dinophysis acuminata and Dinophysis acuta produce lipophilic toxins that cause most shellfish har... more Dinophysis acuminata and Dinophysis acuta produce lipophilic toxins that cause most shellfish harvesting closures in the Atlantic coastal waters of Europe. Dinophysis often exhibit patchy distributions and sampling with conventional methods may fail to detect them. A 6-month calibration study in 2006, plus an additional sampling in 2010 were carried out in Galicia to compare Dinophysis counts obtained from weekly high vertical resolution bottle samples with depth-integrated hose samples. Counts with these two methods were comparable at some depth-ranges, but hose maxima were over one order of magnitude lower under thin-layer scenarios. Estimates from hose samplers should be used with caution in programmes using a "Dinophysis index", either to trigger shellfish sampling or to establish precautionary harvesting closures. In general, hose samplers provide reliable information on the occurrence of Dinophysis except under extreme site-specific hydrodynamic conditions. This study adds new information about the heterogeneous, specific vertical distributions of two Dinophysis spp.
... pH values to be corrected to a temperature of 15°C. Oxygen was measured by the Winkler method... more ... pH values to be corrected to a temperature of 15°C. Oxygen was measured by the Winkler method. ... Chaetoceros didymus Ehrenbcrg Medium-sized oligotnehous ciliates Leptocylindrus danicusCleve Nitzschia senata Cleve Small oligotnehous ciliates RhizosoUma fragihssuna ...
Blooms of Dinophysis spp. associated with lipophilic shellfish toxin outbreaks are common in Nort... more Blooms of Dinophysis spp. associated with lipophilic shellfish toxin outbreaks are common in Northwestern Iberia waters from spring to autumn. Blooms of Dinophysis acuta are very seasonal (late summer-early autumn); they start earlier in Northern Portuguese waters during the upwelling season, and reach their maximum values in the Galician Rías during downwelling events at the end of the upwelling season. There is controversy about whether sudden increases in cell concentrations in the rías result from cross-shelf transport of populations previously established in adjacent shelf waters, or are due to longshore transport that brings populations located off Portugal to the North. In 2005, record concentrations of D. acuta were observed in Portuguese waters (14 Â 10 4 cell L À1) off Aveiro in early September, while concentrations off the Galician coast were very moderate (10 2-10 3 cell L À1). During the autumn transition from upwelling-to downwelling-favourable winds, D. acuta declined abruptly off Portugal while the annual maximum (up to 22 Â 10 3 cell L À1) was found in the Galician Rías. A new approach was used that combined physical observations (SST, current measurements); weekly observations from monitoring programmes in Galicia and Portugal; weekly division rate (m min) estimates of D. acuta in Ría de Vigo, together with monthly transects and additional ad hoc sampling in the Ría. During August and early September, division rates were high in Ría de Vigo but concentrations were low, whereas higher SST values in Portugal (a proxy for thermal stratification) seemed to promote the build up of high densities of D. acuta. During the last week of October and the first week of November, populations declined, whereas in Galicia, maximum concentrations were reached while division rate estimates were almost zero. Results presented here confirm that increased numbers in the Galician Rías are not due to intrinsic growth but to physically driven accumulation; a simple cell concentration budget calculated during the accumulation period suggests that the high net growth observed during downwelling, in the absence of cellular division, must be due to cells imported by longshore transport.
... a CCMM, Conselleria de Pesca, Peirao de Vilaxoán s/n, Vilagarcía de Arousa, Pontevedra, Spain... more ... a CCMM, Conselleria de Pesca, Peirao de Vilaxoán s/n, Vilagarcía de Arousa, Pontevedra, Spain. b Instituto Español de Oceanografía, Cabo Estay, Vigo, Pontevedra, Spain. ... View Within Article. 3.2. Distribution of DAHs and DDPAHs in the Ria de Vigo. ...
Background In past number of methods have been developed for predicting subcellular location of e... more Background In past number of methods have been developed for predicting subcellular location of eukaryotic, prokaryotic (Gram-negative and Gram-positive bacteria) and human proteins but no method has been developed for mycobacterial proteins which may represent repertoire of potent immunogens of this dreaded pathogen. In this study, attempt has been made to develop method for predicting subcellular location of mycobacterial proteins. Results The models were trained and tested on 852 mycobacterial proteins and evaluated using five-fold cross-validation technique. First SVM (Support Vector Machine) model was developed using amino acid composition and overall accuracy of 82.51% was achieved with average accuracy (mean of class-wise accuracy) of 68.47%. In order to utilize evolutionary information, a SVM model was developed using PSSM (Position-Specific Scoring Matrix) profiles obtained from PSI-BLAST (Position-Specific Iterated BLAST) and overall accuracy achieved was of 86.62% with av...
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