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B Strandberg

Publications and source records attributed to B Strandberg.

At least 19 recordsLinked to original sources
PubMed2002

Sustained cholinesterase inhibition in AD patients receiving rivastigmine for 12 months.

OBJECTIVE: To study the long-term dual inhibitory effects of rivastigmine on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in patients with AD. METHODS: Eleven patients with mild AD received rivastigmine for 12 months. Cholinesterase (ChE) activities in the CSF and plasma were assessed colorimetrically. Immunoblot analysis was used to evaluate AChE isoforms. Neuropsychiatric tests were performed throughout the study. RESULTS: At 12 months, the mean dose of rivastigmine was 8.6 mg/d and specific activities of ChE in the CSF were lower than baseline values (by 36% for AChE and 45% for BuChE), correlating with parallel reductions in the plasma (27% for AChE and 33% for BuChE). The reduction of specific activities in the CSF, but not in the plasma, appeared to be dependent on the dose and duration of treatment. Scores of some of the neuropsychological tests associated with memory and attention were correlated with both plasma and CSF AChE and BuChE inhibition for up to 6 months. Immunoblot analysis revealed up-regulation of the "read-through" AChE isoform (AChE-R), whereas levels of the synaptic isoform were unchanged. CONCLUSIONS: Rivastigmine causes persistent inhibition of AChE and BuChE in CSF as well as plasma. The persistent CSF inhibition contrasts with earlier findings after long-term treatment by the reversible ChE inhibitor tacrine, which demonstrated increased AChE activity in the CSF but not in the blood. Rivastigmine's effects on the preferential up-regulation of the AChE-R isoform may have a favorable effect on disease stabilization.

Acetylcholinesterase↗
PubMed2001

Concentrations and spatial variations of polybrominated diphenyl ethers and other organohalogen compounds in Great Lakes air.

Air samples were analyzed from urban, rural, and remote sites near the Great Lakes to investigate the occurrence, concentrations, and spatial and temporal differences of polybrominated diphenyl ethers (PBDE) in air. The concentrations of PBDEs were compared to those of other organohalogen compounds such as PCBs and organochlorine pesticides. The samples were collected in 1997-1999 as part of the Integrated Atmospheric Deposition Network (IADN). To minimize the variability of the data, we selected only samples taken when the atmospheric temperature was 20 +/- 3 degrees C. PBDEs were found in all samples, indicating that these compounds are widely distributed and that they can be transported through the atmosphere to remote areas. The total concentrations of PBDEs were similar to some of the organochlorine pesticides such as sigmaDDT and ranged from 5 pg/m3 near Lake Superior to about 52 pg/m3 in Chicago. In fact, the spatial trend was well correlated to those of PCBs. Our results indicate a relatively constant level from mid-1997 to mid-1999. At 20 +/- 3 degrees C, about 80% of the tetrabromo homologues are in the gas phase and about 70% of the hexabromo homologues are associated with the particle phase. Thus, particle-to-gas partitioning in the atmosphere is an important process for these compounds.

Air Movements↗
PubMed2001

Concentration of organochlorine pesticides in wine corks.

Wine corks were extracted and analyzed for 23 organochlorine pesticides, including alpha-, beta-, and gamma-hexachlorocyclohexanes (HCH), hexachlorobenzene, DDT, DDE and DDD, chlordane, endosulfan, dieldrin, aldrin, and endrin. This was done to investigate the occurrence, concentrations, composition profiles, and possible sources of organochlorine contamination. All groups of compounds were detected in every sample investigated, with the exception of aldrin and endrin. The total concentrations of organochlorine compounds in all samples ranged from 75-120 ng/g lipid, and for most compounds, the concentrations of organochlorines in cork were consistent with published data for other plant tissues. Differences in the relative abundances of the various classes of organochlorine pesticides were substantial and were probably due to differences in the pesticide usage practices of the various regions in which the cork producing trees were grown.

Agriculture↗
PubMed2001

Dietary uptake and elimination of selected polychlorinated biphenyl congeners and hexachlorobenzene in earthworms.

Earthworms (Eisenia foetida) were given food contaminated with hexachlorobenzene (HxCBz) and 20 tetra- to heptachlorinated biphenyls (PCBs). The PCBs were selected to cover a wide range of physicochemical properties. The uptake efficiencies, uptake rate constants, and elimination rate constants in worms varied between the 20 PCBs. The uptake efficiencies were between 10 and 68%. The PCBs that were eliminated fastest contained few chlorine atoms, had more polar characteristics, and were sterically hindered. Slowest was the elimination for less polar PCBs with six or seven chlorine atoms such as the non-ortho-substituted PCB 169. Elimination half-lives varied between 6 and 25 d. The biomagnification factors (BMFs) for the PCBs and HxCBz averaged 0.1 based on lipids and 0.04 based on wet (worms) and dry (food) weight. Worm cocoons were analyzed for PCBs for the first time. The PCB pattern in the cocoons differed from the adult worms by the comparatively higher load of non-ortho PCBs. By studying congeners covering a large range of PCB physicochemical characteristics, their fate within the environmental and the factors influencing biological responses can be better understood.

Animals↗
PubMed2000

[Residues of chlordane in fish in the Gulf of Gdańsk].

Concentrations, composition and spatial variations of the residues of the pesticide Chlordane were determined in several species of fish caught in Gulf of Gdańsk. The residues of Chlordane (cis-i trans-chlordane, cis-i trans-nonachlor, oxychlordane, heptachlor, heptachlor epoxide, MC4, MC5, MC6, MC7, U82 and U83) were found in all fish examined, however, the concentrations noted were low, i.e. from 0.40 to 12 ng/g wet weight. Among the Chlordane constituents and metabolites determined trans-naonachlor, cis-chlordane, oxychlordan, heptachlor epoxide, cis-nonachlor, MC5, MC6 and trans-chlordane were dominated, and MC4, MC7, U82 and U83 were minor compounds. No heptachlor residues were found in fish examined. A small concentrations and specific composition of the residues of Chlordane and its metabolites determined in fish from the Gulf of Gdańsk do indicate on a distant sources of pollution with that pesticide--mainly transported and deposited via the atmosphere.

Animals↗
PubMed1999

[Dieldrin, aldrin, endrin, isodrin, endosulfan 1 and 2 on fish in the Gulf of Gdańsk].

The residues of dieldrin, aldrin, endrin, isodrin, endosulfan 1 and 2 has been determined in a several species of fish caught in the Gulf of Gdańsk in 1992. The method of measurement was capillary gas chromatograph and low resolution mass spectrometry (HRGC/LRMS) after a nondestructive extraction and clean-up step with a further fractionation of the extract on Florisil column. Apart from dieldrin no other cyclodiene pesticides studied were found in fishes in detectable amounts, and for dieldrin concentrations ranged from 0.84 to 6.6 ng/g wet weight.

Animals↗
PubMed1999

[DDT and it metabolites in fish in the Gulf of Gdańsk].

The residues of DDT and its metabolites (DDTs; p,p'-DDT, o,p'-DDT, p,p'-DDD, o,p'-DDD, p,p'-DDE, o,p'-DDE i p,p'-DDMU) has been determined in ten species of edible fish caught in the Gulf of Gdańsk in 1992. The method of measurement was capillary gas chromatography and low resolution mass spectrometry (HRGC/LRMS) after a nondestructive extraction and clean-up step with a further fractionation of the extract on Florisil column. All fish examined contained detectable residues of DDTs, and the concentrations ranged from 28 to 310 ng/g wet weight. o,p'-DDT accounted from 0.4 to 2.5% to DDTs content. The residue concentration of DDTs in herring (110 ng/g wet weight and 1100 ng/g lipid weight) in 1992 was threefold lower than in the years 1979-1983 and fourteen fold lower than in 1969-1973.

Animals↗
PubMed1998

Concentrations, biomagnification and spatial variation of organochlorine compounds in a pelagic food web in the northern part of the Baltic Sea.

Zooplankton, mysis (Mysis sp.) and herring (Clupea harengus) were collected at two pelagic locations in the northern part of the Baltic Sea, one in Bothnian Bay (BB) and the other in the Bothnian Sea (BS), in order to investigate concentrations, composition profiles, biomagnification features and spatial differences of organochlorine contaminants. Compounds included in this study are hexachlorocyclohexanes (HCHs), DDTs, hexachlorobenzene (HCBz), chlordanes (CHLs), dieldrin, mirex and polychlorinated biphenyls (PCBs). All groups of compound were detected in every sample investigated, with the exception of mirex that was detected only in the herring samples. The concentrations of organochlorine compounds in all samples ranged, e.g. from 250 to 1500 ng/g lipid for PCBs and from 6 to 150 ng/g lipid for CHLs. The biomagnification factor (BMF) is calculated as the concentration of the compounds in the organism divided by the concentration in food normalised to lipids. In the zooplankton-mysis-herring food web, large variations in BMFs between the different compound groups were observed. The highest BMFs were obtained for the CHLs followed by the DDTs and the lowest for the HCHs. Nonachlorinated CHLs had the highest BMFs within the group of CHLs and for the DDTs p,p'-DDT had a higher biomagnification potential than its metabolites p,p'-DDE and p,p'-DDD. Finally, concentration and biomagnification differences between the two stations were observed. The herring in the southernmost station (BS) displayed approximately two- to sixfold higher biomagnification than the herring from the north (BB).

Animals↗
PubMed1998

Concentrations and spatial variations of cyclodienes and other organochlorines in herring and perch from the Baltic Sea.

Herring (Clupea harengus) and perch (Perca fluviatilis) were collected in the northern and southern Baltic Sea and analyzed for the presence of the cyclodiene pesticides chlordane (CHL), heptachlor, aldrin, dieldrin, endrin, isodrin, endosulfan and mirex, as well as other organochlorine contaminants, hexachlorocyclohexanes (HCHs), DDTs, hexachlorobenzene (HCBz) and polychlorinated biphenyls (PCBs) in order to investigate concentrations, accumulation and differences in geographical distribution. In the northern part of the Baltic Sea, Gulf of Bothnia, herring were collected at two pelagic stations, one in the Bothnian Bay (BB) and the other in the Bothnian Sea (BS), respectively; perch were collected at four coastal locations along the Swedish coast. All these locations were selected to represent background areas except one in the vicinity of an industrialised and contaminated area. Both specimens were also caught in the southern part of the Baltic Sea, in the Gulf of Gdansk (GG), Poland, a potentially highly polluted area. From the eight cyclodiene pesticides analyzed, three were detected in herring and perch samples, including 12 different CHL-related compounds, dieldrin and mirex. To our knowledge, it is the first time that mirex has been detected in samples from the Baltic Sea. Neither heptachlor, aldrin, endrin, isodrin nor endosulfan were found. However, HCHs, DDTs, HCBz and PCBs were found in every sample investigated, and the concentrations ranged e.g. for the cyclodiene chemicals dieldrin and CHL-related compounds from 30 to 170 ng/g lipid and for PCBs from 360 to 5400 ng/g lipid, both fish species included. Differences in contamination burden between the sites can be seen, e.g. for herring the BB and GG locals were similar, and generally lower than BS for all chemicals except that of DDT where GG was the highest. For the perch samples the industrialised location had markedly higher concentrations of HCBz and PCBs than the other locations. This species also identifies GG as the most DDT contaminated site among the three studied areas.

Animals↗
PubMed1998

Dialysis with semipermeable membranes as an efficient lipid removal method in the analysis of bioaccumulative chemicals.

Herein is a procedure described using a semipermeable membrane (SPM) for enrichment of organic chemicals from lipid-containing samples. Dialysis with SPMs in an organic solvent can separate organochlorine contaminants such as non-, mono-, and di-o-PCBs, PCDDs, PCDFs, PCDTs, PCNs, pesticides, and PAHs from lipids. The method is nondestructive and more than 20 g of lipid can be dialyzed in a single membrane with acceptable recoveries of the internal standards, nearly independent of amount and type of lipid dialyzed. The lipid removal process shows good consistency between subsamples, and the lipid content can be reduced by 90-99%, depending on species and amount lipid. Neither triglycerides nor phospholipids were obtained in the dialysate fraction. The utility and reliability of the method is displayed by good precision for 72 PCBs and 27 organochlorine pesticides in the concentration range 0.05-50 micrograms/sample for triplicate subsamples, by the consistency in PCDD/F levels compared to a classic analytical procedure, and by the analysis of the above listed chemicals in approximately 200 biological samples of a wide variety of types. This technique can also be used as an enrichment device for contaminants when huge amounts of lipids are extracted for toxicological studies. Moreover, it is possible to use SPM to cleanup other samples from molecules with relatively high masses, e.g. sediments, soil, compost, and tar materials.

Animals↗
PubMed1997

Concentrations and biomagnification of polychlorinated naphthalenes in black cormorants Phalacrocorax carbo sinensis from the Gulf of Gdańsk, Baltic Sea.

Black cormorants, Phalacrocorax carbo sinensis (the breast muscles and liver) originating from the colony near Katy Rybackie on the south coast of the Gulf of Gdańsk, Baltic Sea, were collected in 1992 and analysed for polychlorinated naphthalenes. PCNs were determined employing a multi-residue procedure including a non-destructive wide-bore open-tube extraction step, cleanup using semipermeable polyethylene membrane, HPLC fractionation of planar compounds on activated carbon column and final separation and identification and quantification with HRGC/HRMS. Tetra- to hepta-CNs were found in all samples examined, and penta- and next tetra-CNs were dominating homologue groups. Dominating members in the fingerprint of PCNs in black cormorants were 1,3,5,7-T4CN (no. 42); 1,2,3,5,7-/1,2,4,6,7-P5CN (no. 52/60); 1,2,4,6,8-P5CN (no. 61); 1,2,3,4,6,7-/1,2,3,5,6,7-H6CN (no. 66/67); 1,2,4,6-/1,2,4,7-/1,2,5,7-T4CN (no. 33/34); 1,2,4,5,7-P5CN (no. 58); and 1,2,4,7,8-P5CN (no. 62). When related to potential food items, black cormorants biomagnify in their body many PCNs and the congeners no. 42 and 66/67 show highest biomagnification factor (BMF) values.

Animals↗
PubMed1997

Presentation of a foreign peptide on the surface of tomato bushy stunt virus.

A 13-amino-acid peptide derived from the V3 loop of human immunodeficiency virus (HIV-1) glycoprotein 120 (gp120) was attached as a C-terminal gene fusion to the coat protein of tomato bushy stunt virus (TBSV). The architecture of this plant virus permitted external display of the foreign sequence 180 times on the surface of the chimaeric virus particle. The chimaera replicated to a level similar to wild-type TBSV and the foreign sequence was retained through six sequential passages in plants. The HIV epitope was detected on the surface of the virus capsid by a V3-specific monoclonal antibody and by human sera from HIV-1-positive patients, demonstrating the potential of using plant-derived chimaeric particles for diagnostic purposes. Chimaeric virus also induced a specific immune response to the foreign HIV epitope when injected into NMRI mice.

Animals↗
PubMed1997

[Compounds from the chlordane group in adipose tissue of harbour seals from the Gulf of Gdansk].

The composition and the concentration of chlordanes were shown in blubber of harbour porpoises collected from the Gulf of Gdańsk, Baltic Sea, in 1991-1992. Chlordanes were determined using capillary gas chromatography and low resolution mass spectrometry (HRGC/LRMS). The range of CHLs concentration in blubber was between 420-1000 ng/g wet weight (470-1300 ng/g lipid weight). The composition of CHLs residues was similar in males and females, with trans-nonachlor (37%) as a most abundant compound, and followed by heptachlor epoxide (15%), cis-chlordane (14%), cis-nonachlor (14%), oxychlordane (11%), MC6 (3%), MC5 (2%), trans-chlordane, MC7, U82 and MC4 (< 1%).

Adipose Tissue↗
PubMed1996

[Investigation on spatial distribution of chloronaphthalenes in flounder Platychtis flesus from the gulf of Gdansk].

Flounders from the three different and relatively distant sites in the Gulf of Gdańsk were collected in august and october 1992 and analysed to investigate a potential differences in concentration and composition of chloronaphthalenes. The method of PCNs measurement was capillary gas chromatography and high resolution mass spectrometry (HRGC/HRMS) after a nondestructive extraction and cleanup step via dialysis with polyethylene membrane and than HPLC preseparation on a activated carbon column. Chloronaphthalenes were separated and quantified on RTx-5 capillary column using an electron impact (EI) mode and selective ion recording (SIR). All samples contained detectable concentrations of many tetra-, penta- and heksachloronaphthalenes, and the total PCNs concentration ranged from 1700 to 3900 pg/gwet weight. A substantial difference in pattern and concentration of PCNs residues in flounders between some of the sampling sites were found.

Animals↗
PubMed1996

[Polychlorinated naphthalenes in Harbour porpoises Phocoena phocoena].

Concentration and composition of chloronaphthalenes (PCNs) were determined in blubber of two male and two female porpoises from the Gulf of Gdańsk. Porpoises examined died in the fishing nets in 1992. Polychlorinated naphthalenes were determined using capillary gas chromatography and high resolution mass spectrometry (HRGC/HRMS) after nondestructive cleanup with polyethylene membrane, and pre-separation of planar compounds on carbon HPLC column. 28 peaks from chloronaphthalenes were identified and quantified on a chromatogram. Concentration of total PCNs in blubber of male porpoises were 1.7-2.4 ng/glipid weight, and of female 2.0-2.4 ng/g. Among of the PCN congeners found 1,2,3,4,6,7-/1,2,3,5,6,7-hexachloronaphthalene (PCN nr 66/67) and 1,2,4,6-/1,2,5,7-tetrachloronaphthalene (PCN nr 3/34/37) were dominating compounds, followed by 1,4,6,7-tetrachloronaphthalene (PCN nr 47), 1,2,3,5-/1,3,5,8-tetrachloronaphthalene (PCN nr 28/43) and 1,2,3,5,7-/1,2,4,6,7-pentachloronaphthalene (PCN nr 52/60), and others were minor contributors.

Adipose Tissue↗
PubMed1996

[Dioxins and furans in edible species of fish from the Gulf of Gdańsk].

The levels of PCDDs and PCDFs in samples of lamprey, perch, herring, cod, flounder, round goby, eelpout and pikeperch caught in the Gulf of Gdańsk were determined by HRGC/HRMS. The results are expressed as TCDD equivalents, calculated according to international (I-TEQs), nordic (N-TEQs) models. The levels (pg TEQs/g wet weight) were from 0.263 in lamprey to 6.047 in herring (I-TEQs). Except of herring nearly all fish species sampled contained PCDDs and PCDFs in concentration below 1 pg TEQs/g wet wt, and only for pikeperch it was 1.025 pg S-TEQs/g.

Adipose Tissue↗