Prostate-specific antigen flare induced by 223RaCl2 in patients with metastatic castration-resistant prostate cancer.

PURPOSE: Prostate-specific antigen (PSA) flare is a well-known phenomenon in patients with prostate cancer, but its impact during radium-223 dichloride (223RaCl2) therapy is still unclear. This radioisotope has shown to improve overall survival in metastatic castration-resistant prostate cancer (mCRPC). We sought to evaluate the impact of PSA flare on survival and its relation with metabolic parameters on 18F-labeled sodium fluoride PET/CT. METHODS: We conducted a retrospective study of 168 patients with mCRPC (median age 69; median PSA 29.7) receiving 223RaCl2. Overall survival (OS) and progression-free survival (PFS), estimated by the Kaplan-Meier method and compared using a log-rank test, were evaluated for patient groups corresponding to different definitions of PSA flare. Metabolic 18F-fluoride PET/CT data were analyzed as well. RESULTS: Immediate PSA decline was observed in 49 patients (29.2%), whereas no PSA response was observed in 59 patients (35.1%). PSA flare (defined as rise after the first cycle followed by decrease below the baseline) was observed in 20 patients (11.9%) and PSA flare followed by a decrease from peak but not below baseline was observed in 40 (23.8%). The first flare subgroup had a median PFS and OS of 20.8 and 23.9 months, respectively. These outcomes were not significantly different from patients with immediate PSA decrease, but were significantly better than in patients with persistent PSA elevation (3.1 months for PFS and 11.5 months for OS, p < 0.001). Moreover, the PSA flare group showed an alkaline phosphatase (ALP) decrease significantly greater than non-responders (p = 0.003). Metabolic 18F-fluoride PET/CT data were available in 35 patients at baseline and during 233RaCl2 therapy. The tumor burden reduction, expressed by ΔTLF10 and ΔFTV10, was more evident within PSA flare group below baseline than non-responders (p = 0.005 and 0.001, respectively). CONCLUSIONS: This report suggests that a flare does not necessarily indicate lack of response to 223RaCl2 therapy.

Photochemical and microbial alterations of DOM spectroscopic properties in the estuarine system Ria de Aveiro.

The influence of photochemical transformations of chromophoric dissolved organic matter (CDOM) on microbial communities was evaluated in the estuarine system Ria de Aveiro. Two sites, representative of the marine and brackish water zones of the estuary, were surveyed regularly in order to determine seasonal and vertical profiles of variation of CDOM properties. Optical parameters of CDOM indicative of aromaticity and molecular weight were used to establish CDOM sources, and microbial abundance and activity was characterized. Additionally, microcosm experiments were performed in order to simulate photochemical reactions of CDOM and to evaluate microbial responses to light-induced changes in CDOM composition. The CDOM of the two estuarine zones showed different spectral characteristics, with significantly higher values of the specific ultra-violet absorbance at 254 nm (SUVA254) (5.5 times) and of the absorption coefficient at 350 nm (a350) (12 times) and lower SR (S275-295/S350-400) ratio at brackish water compared with the marine zone, reflecting the different amounts and prevailing sources of organic matter, as well as distinct riverine and oceanic influences. At the marine zone, the abundance of bacteria and the activity of Leu-AMPase correlated with a350 and a254, suggesting a microbial contribution to the HMW CDOM pool. The irradiation of DOM resulted in a decrease of the values of a254 and a350 and an increase of the slope S275-295 and of the ratios E2 : E3 (a250/a365) and SR, which in turn increase its bioavailability. However, the extent of photoinduced transformations and microbial responses was dependent on the initial optical characteristics of CDOM. In Ria de Aveiro both photochemical and microbial processes yielded optical changes in CDOM and the overall results of these combined processes determine the fate of CDOM in the estuarine system and have an influence on local productivity and in adjacent coastal areas.

BDE-209: kinetic studies and effect of humic substances on photodegradation in water.

BDE-209 is a brominated flame retardant and a priority contaminant, which has been found in several environmental matrices, namely, in water. To date, there are no quantum yield data for BDE-209 photodegradation by sunlight in water, to allow predicting half-life times in aquatic systems. In this work, the kinetics of BDE-209 photodegradation in water was studied and the influence of different fractions of aquatic humic substances (HS) was evaluated. Aqueous solutions of BDE-209 exposed for different periods of time to simulated sunlight were analyzed by HPLC-UV after being concentrated using dispersive liquid-liquid microextraction (DLLME) or solid-phase extraction (SPE). The photodegradation of BDE-209 in aqueous solution followed pseudo-first-order kinetics. The average quantum yield obtained of 0.010 ± 0.001 (about 20-fold lower than the quantum yield determined in ethanol) allow to predict an outdoor half-life time of 3.5 h. The photodegradation percentage of BDE-209 was not significantly affected by the XAD-4 fraction of HS, but it decreased substantially in the presence of humic and fulvic acids. Light screening by the humic substances could not explain this delay, which is probably the result of the association of the compound with the hydrophobic sites of the humic material.

Ex vivo antimicrobial efficacy of the EndoVac system plus photodynamic therapy associated with calcium hydroxide against intracanal Enterococcus faecalis.

AIM: To evaluate the ex vivo efficacy of the EndoVac system and photodynamic treatment (PDT) as adjuncts to chemomechanical debridement associated with calcium hydroxide (CaOH2 ) in reducing the levels of intracanal Enterococcus faecalis. METHODOLOGY: One hundred and twenty-five sterile premolar teeth were conventionally accessed, prepared and then contaminated with E. faecalis (ATCC 29212) for 30 days. Teeth were randomly divided into 4 groups: Control (chemomechanical debridement with conventional irrigation); Endovac (chemomechanical debridement with EndoVac system); PDT (chemomechanical debridement with conventional irrigation and PDT) and Endovac+PDT (chemomechanical debridement with EndoVac and PDT). The irrigants used in all groups were 5.25% sodium hypochlorite and 17% EDTA. After treatment, an intracanal dressing (CaOH2 ) was applied in all canals for 7 days. Samples were obtained before (T1) and after the therapeutic procedures (T2) and, after intracanal medication (T3), plated onto BHI media and incubated (37 °C, 48 h) to determine the colony-forming units (CFU mL(-1) ). RESULTS: The overall mean cell counts (CFU mL(-1) ) of E. faecalis were high at the initial contamination (T1). A significant reduction (P < 0.05) of E. faecalis mean counts was observed in all groups from baseline (T1) to both post-therapy samplings (T2 and T3); no differences amongst the groups were detected. No significant change in bacterial counts from T2 to T3 was detected. CONCLUSION: The adjunctive use of the EndoVac system and the photodynamic treatment, in combination or not, was as effective as the conventional chemomechanical debridement associated with CaOH2 on reducing the counts of intracanal E. faecalis.

Fluorescence and DOC contents of estuarine pore waters from colonized and non-colonized sediments: effects of sampling preservation.

The influence of the colonization of salt marsh sediments with Halimione portulacoides was evaluated by analysing the fluorescent dissolved organic matter (FDOM) in sediment pore waters from a salt marsh at different depths. Cores of sediments at colonized and non-colonized sites were collected from a coastal lagoon (Ria de Aveiro, Portugal). The DOC content of extracted pore waters was determined and characterized by synchronous molecular fluorescence (Deltalambda=60nm) and UV-visible spectroscopies. The common practice of freezing sediment cores for further and later chemical investigation was shown not to be an appropriate methodology of sample preservation. On the contrary, freezing of extracted and filtered pore water seemed not to affect either the DOC content or the fluorescence properties of pore waters. Two types of fluorescent substances were found in the pore waters spectra; one corresponding to humic-like substances and another one resembling proteins. However, major differences were found in the spectra of pore waters depending on both depth and the presence/absence of vegetation colonization.

Antibacterial activity of oxytetracycline photoproducts in marine aquaculture's water.

Oxytetracycline (OTC) is one of the most used antibiotics in aquaculture. The main concern related to its use is the bacterial resistance, when ineffective treatments are applied for its removal or inactivation. OTC photo-degradation has been suggested as an efficient complementary process to conventional methods used in intensive fish production (e.g.: ozonation). Despite this, and knowing that the complete mineralization of OTC is difficult, few studies have examined the antibacterial activity of OTC photoproducts. Thus, the main aim of this work is to assess whether the OTC photoproducts retain the antibacterial activity of its parent compound (OTC) after its irradiation, using simulated sunlight. For that, three Gram-negative bacteria (Escherichia coli, Vibrio sp. and Aeromonas sp.) and different synthetic and natural aqueous matrices (phosphate buffered solutions at different salinities, 0 and 21‰, and three different samples from marine aquaculture industries) were tested. The microbiological assays were made using the well-diffusion method before and after OTC has been exposed to sunlight. The results revealed a clear effect of simulated sunlight, resulting on the decrease or elimination of the antibacterial activity for all strains and in all aqueous matrices due to OTC photo-degradation. For E. coli, it was also observed that the antibacterial activity of OTC is lower in the presence of sea-salts, as demonstrated by comparison of halos in aqueous matrices containing or not sea-salts.

Mosquitoes (Diptera: Culicidae) from crepuscular period in an Atlantic Forest area in Southern Brazil.

Crepuscular period is one of the factors that may influence the biting activity of mosquitoes. Many of these insects have a peak activity in this period. The purpose of this study was to investigate the afternoon crepuscular activity of Culicidae in a remaining area of Atlantic Forest in western Santa Catarina, southern Brazil. Moreover, the possible influence of abiotic factors, the abundance and species richness were verified. In order to better analyze the influence of crepuscular period in specific composition and abundance of mosquitoes, the dusk was divided into three periods: pre-sunset, sunset and post-sunset. At the end of the study, nine hundred and eight four specimens distributed in 12 genera and 23 species were collected. Trichoprosopon pallidiventer (Lutz, 1905) (59.76%), Aedes crinifer (Theobald, 1903) (8.13%), Ae. scapularis (Rondani, 1848) (5.89%) were the most abundant species. Spring time presented the greatest abundance and species richness. During the study, among the three periods evaluated, pre-sunset had the greatest abundance and post-sunset the lowest. Pre-sunset and sunset had the greatest similarity between species. Regarding to the abiotic factors evaluated seven and 15 days before sampling, they did not present significant correlation for the three most abundant species. However, temperature had a positive correlation to these species. Moreover, the correlation between collected species and its possible role as vectors of etiological agents of diseases was discussed.

Use of sunlight to degrade oxytetracycline in marine aquaculture's waters.

Oxytracycline (OTC) is a broad spectrum antibiotic authorized for use in European aquaculture. Its photo-degradation has been widely studied in synthetic aqueous solutions, sometimes resorting to expensive methods and without proven effectiveness in natural waters. Thus, this work studied the possibility to apply the solar photo-degradation for removal of OTC from marine aquaculture's waters. For that, water samples were collected at different locals of the water treatment circuit, from two different aquaculture companies. Water samples were firstly characterized regarding to pH, salinity, total suspended solids (TSS), organic carbon and UV-Vis spectroscopic characteristics. Then, the samples were spiked with OTC and irradiated using simulated sunlight in order to evaluate the matrix effects on OTC photo-degradation. From kinetic results, the apparent quantum yields and the outdoor half-life times, at 40°N for midsummer and midwinter days were estimated by the first time for these conditions. For a midsummer day, at sea level, the outdoor half-life time predicted for OTC in these aquaculture's waters ranged between 21 and 25 min. Additionally, the pH and salinity effects on the OTC photo-degradation were evaluated and it has been shown that high pH values and the presence of sea salt increase the OTC photo-degradation rate in aquaculture's waters, compared to results in deionised water. The results are very promising to apply this low-cost methodology using the natural sunlight in aquaculture's waters to remove OTC.

An antibody to CD44 enhances hematopoiesis in long-term marrow cultures.

Monoclonal antibody S5, which is specific for CD44, facilitates engraftment of major histocompatibility complex (MHC)-mismatched canine bone marrow (BM) when infused into recipient animals before total body irradiation (TBI) and marrow infusion. The precise mechanism by which S5 facilitates engraftment is not known. Previously published data in a murine long-term bone marrow culture (LTBMC) model with other anti-CD44 monoclonal antibodies (mAbs) demonstrated an abrogation of myelo- and lymphopoiesis in LTBMC. To address this issue in an in vitro setting, the effect of S5 on canine myelopoiesis in LTBMC was investigated. The data indicate that treatment of LTBMC with S5 causes an absolute increase in the number of progenitor cells as measured by a colony-forming unit-granulocyte/macrophage (CFU-GM) assay compared to cultures treated with control mAb (p < 0.0001). This effect was not observed with three other anti-CD44 mAbs used (Hermes-1, S3, and IM7). In addition, a concomitant decrease in the production of nonadherent cells was noted (p < 0.0001). These effects were evident in both autologous and allogeneic LTBMC systems. mAb S5 has been shown to enhance natural killer (NK) activity, and more recent data indicate the increased cytoxic effect to be partially mediated through CD18. Thus, a possible role for modulation of the CD18 antigen in LTBMC by S5 was assessed by addition of the anti-CD18 mAb 60.3. While the S5-induced reduction in total nonadherent cell production was not changed by addition of 60.3, the increase in progenitor cells stimulated by S5 was abrogated. These findings suggest a role for anti-CD44 antibody in changes in the marrow microenvironment that may be responsible for facilitation of donor engraftment and, at least in part, CD18 may be involved in this phenomenon. The establishment of this in vitro LTBMC model will enable the mechanism to be further dissected.

Lysis of keratinocytes by IL-2-activated peripheral blood lymphocytes.

Interleukin 2 (IL-2)-activated peripheral blood mononuclear cells (PBMC) have been reported to lyse tumor cells while essentially sparing normal cells in vitro. This report concerns IL-2-induced anti-keratinocyte (anti-KC) cytotoxic effectors that lyse normal human keratinocytes (KC) in vitro. Effectors were generated by culturing PBMC for 1-8 d in various concentrations of recombinant IL-2 and then assayed against 51Cr-labeled targets. Effectors stimulated with 10(3) U/ml of IL-2 for 8 d readily lysed adherent or trypsinized autologous or allogeneic KC cultured in serum-free medium. Induction of anti-KC effectors was IL-2 dose-dependent, with as little as 12-25 U/ml of IL-2 inducing increased anti-KC activity after 24 h of treatment. Although anti-KC activity was increased after overnight culture in IL-2, maximal effector potency in terms of lytic units (LU) per 10(6) effector cells required 4 d of IL-2 treatment. Maximal effector yield in terms of LU per input PBMC occurred after 8 d of IL-2 treatment. Antibody plus complement depletion studies showed that the anti-KC effectors predominantly have a CD16 --/CD3 --/CD2+ phenotype. A natural killer (NK)-like specificity of the effectors was suggested by two findings: unlabeled K562 cells totally inhibited lysis of 51Cr-KC in cold target competition assays, and interferon gamma (IFN-g) treatment (2.5 U/ml-500 U/ml of recombinant IFN-g for 48-72 h) down-regulated KC susceptibility to lysis by these effectors. Thus, IL-2 treatment of PBMC induces non-T cell, natural killer-like effectors that can lyse both autologous and allogeneic KC. Furthermore, KC resemble other cell types that become resistant to non-MHC-restricted lysis after treatment with IFN-g. Finally, the contrasting effects of IFN-g treatment on KC lysis by these effectors, as opposed to lysis by specific T cells, suggests that IFN-g could promote a shift from non-MHC-restricted to MHC-restricted KC lysis during epidermal immune responses in vivo.

Recognition of keratinocytes by cytotoxic T cells specific for conventional HLA class-I alloantigen.

This study analyzed whether human keratinocytes (KC) express conventional HLA class-I molecules as detected by class-I-specific cytotoxic T lymphocytes (CTL), and whether exposure of KC to interferon-gamma (IFN-g) is required for CTL recognition. Basal KC grown in serum-free medium and exposed to recombinant IFN-g for 24-96 h were used as targets in 51Cr-release assays. Target-cell susceptibilities to lysis were compared by analyzing the lytic unit (LU) activity of a given CTL population against IFN-g-treated and untreated KC. CTL effectors were cloned from alloantigen-primed cultures by limiting dilution in the presence of antigenic B lymphoblastoid cells (BCLL) and IL-2. These T-cell clones lysed appropriate BCLL and PHA blasts but not third-party BCLL or K562. Lysis of antigenic BCLL was specifically blocked by antibodies against CD3 or class-I antigens. Specificity of the clones for conventional class-I antigen was demonstrated by cytotoxicity tests employing a panel of HLA-typed BCLL. The clones specifically lysed KC syngeneic with the original effector immunogen, and lysis was also blocked by anti-class-I antibodies. The effect of IFN-g treatment was to increase KC susceptibility to lysis by these clones. From 3-25 times more LU were measured against IFN-g-treated KC than against nontreated KC, and the degree of enhancement was similar for KC treated with concentrations of IFN-g ranging from 2.5-200 U/ml. This effect of IFN-g treatment on KC lysis by CTL, which was detected after only 24 h at all doses tested, emphasizes the potential role of IFN-g in enhancing CTL-mediated antiviral epidermal immunity and in exacerbating epidermal disease mediated by specific lytic T cells. In addition, the finding that normal human KC can be recognized by MHC class-I-specific CTL demonstrates that KC do express conventional class-I-antigens and that KC lysis by CTL can occur independently of exogenous cytokines.

The use of an anti-TCRalphabeta monoclonal antibody to control host-versus-graft reactions in canine marrow allograft recipients conditioned with low dose total body irradiation.

BACKGROUND: A limitation in the application of marrow transplantation has been complications related to the conditioning regimens that have been intensified to the point where organ toxicities have been common, resulting in morbidity and mortality. METHODS: A conditioning regimen consisting of low-dose total body irradiation (TBI*) was used to test whether postgrafting therapy with a monoclonal antibody (mAb) against the T cell receptor (TCR)alphabeta facilitated sustained engraftment of marrow from dog leukocyte antigen (DLA)-identical canine littermates. The anti-TCRalphabeta mAb 15.9D5 was selected for in vivo studies because it induced hyporesponsiveness to allogeneic stimulator cells in mixed leukocyte culture and was not mitogenic in vitro. RESULTS: When recipients of genotypically DLA-identical marrow were conditioned by the barely "lethal" dose of 450 cGy TBI alone, almost 60% of grafts failed (n=39). The remainder engrafted, either in the form of stable mixed donor/host or all donor hematopoietic chimerism. In contrast to results in controls, 5 of 6 dogs that were given, in addition, a loading dose of mAb 15.9D5 of 1 mg/kg on day -1, 450 cGy TBI on day 0, followed by mAb at 0.3 mg/kg/day until day +7, showed sustained engraftment (P=.058). To accomplish a comparable rate of engraftment in the absence of anti-TCRalphabeta antibody, 920 cGy TBI were needed for pretransplant conditioning. CONCLUSIONS: Results strongly suggested that in vivo administration of a mAb against TCRalphabeta prevented rejection of allogeneic marrow grafts in the setting of conditioning with a relatively nontoxic but otherwise suboptimal dose of 450 cGy TBI. In vivo administration of m Ab 15.9D5 was well tolerated without any noticeable side effects. The exact mechanism by which the mAb works in vivo is as yet poorly understood, but it does not involve CD3/TCR complex modulation or elimination of T cells from the circulation.

Metabolic cholesterol depletion hinders cell-surface trafficking of the nicotinic acetylcholine receptor.

The effects of metabolic inhibition of cholesterol biosynthesis on the trafficking of the nicotinic acetylcholine receptor (AChR) to the cell membrane were studied in living CHO-K1/A5, a Chinese hamster ovary clonal line that heterologously expresses adult alpha2betadeltaepsilon mouse AChR. To this end, we submitted CHO-K1/A5 cells to long-term cholesterol deprivation, elicited by Mevinolin, a potent inhibitor of 3-hydroxy-3-methyl-glutaryl-CoA reductase and applied a combination of biochemical, pharmacological and fluorescence microscopy techniques to follow the fate of the AChR. When CHO-K1/A5 cells were grown for 48 h in lipid-deficient medium supplemented with 0.5 microM Mevinolin, total cholesterol was significantly reduced (40%). Concomitantly, the maximum number of binding sites (Bmax) of the cell-surface AChR for the competitive antagonist alpha-bungarotoxin was reduced from 647+/-30 to 352+/-34 fmol/mg protein, i.e. by 46%. The apparent dissociation constant (Kdapp) for alpha-bungarotoxin of the AChRs remaining at the cell surface was not modified by cholesterol depletion. Similarly, the half-concentration inhibiting the specific binding of the radioligand (IC50) for another competitive antagonist, d-tubocurarine, did not differ from that in control cells. The decrease in cell-surface AChR was paralleled by an increase in intracellular AChR levels, which rose from 44+/-2.1% in control cells to 74+/-3.3% in Mevinolin-treated cells. When analyzed by wide-field fluorescence microscopy, the fluorescence signal arising from alpha-bungarotoxin labeled cell-surface AChRs was reduced by approximately 70% in Mevinolin-treated cells. The distribution of intracellular AChR also changed: Alexa594-alpha-bungarotoxin-labeled AChR exhibited a highly compartmentalized pattern, concentrating at the perinuclear and Golgi-like regions. Temperature-arrest of protein trafficking magnified this effect, emphasizing the Golgi localization of the AChR. Colocalization studies using the transiently expressed fluorescent trans-Golgi/trans-Golgi network marker pEYFP/human beta1,4-galactosyltransferase and the trans-Golgi network marker syntaxin 6 provided additional support for the Golgi localization of intracellular AChRs. The low AChR cell-surface expression and the increase in intracellular AChR pools in cholesterol-depleted cells raise the possibility that cholesterol participates in the trafficking of the receptor protein to the plasmalemma and its stability at this surface location.

An anti-CD44 antibody does not enhance engraftment of DLA-identical marrow after low-dose total body irradiation.

920 cGy total body irradiation (TBI) is adequate for consistently successful engraftment of marrow from dog leukocyte antigen (DLA)-identical littermates; however, the dose is inadequate to ensure a marrow graft from DLA-nonidentical unrelated donors. Such mismatched grafts are successful only after 1800 cGy, given in three fractions. While anti-T-cell reagents enhance engraftment of DLA-identical littermate marrow after 920 cGy, they fail to be effective in the DLA-nonidentical setting. However, a monoclonal antibody (mAb) to CD44, S5, was found to be very effective in enhancing engraftment of DLA-nonidentical marrow. The current study asked whether mAb S5 was also effective in the setting of DLA-identical littermate transplants. To this purpose, the TBI dose was lowered to 450 cGy, a dose after which 70% of such grafts failed. Four dogs were treated with antibody S5, 0.2 mg/kg on days -7 through -2 (per previously published protocol), given 450 cGy TBI followed by marrow grafts from their DLA-identical littermates. All four dogs rejected their grafts; two of these died from marrow aplasia, and two survived with endogenous marrow recovery. This result was not statistically significantly different from that in 17, historical (n = 5) and concurrent (n = 12), control dogs where 11 of 17 animals rejected. Even if ten experimental animals were transplanted and all six remaining dogs engrafted, the results still would not have been significantly different from control. This result is in contrast to the successful engraftment promoted by pretreatment with antibody S5 of DLA-nonidentical unrelated dogs, consistent with the notion that different host cells are involved in graft rejection in the two disparate histocompatibility settings.

Myogenic differentiation of the muscle clonal cell line BC3H-1 is accompanied by changes in its lipid composition.

Phospholipid and neutral lipid composition was studied in the course of myogenic differentiation of the clonal cell line BC3H-1. Total phospholipid content increased during differentiation, predominantly in the major classes of choline and ethanolamine glycerophospholipids. The contents of other lipids, such as triacylglycerols, diminished more than 50% during this period. The content and distribution of fatty acids also underwent marked differentiation-dependent changes. The polyunsaturated (tetrapenta- and hexaenoic) fatty acid species of several phospholipid classes diminished during differentiation, especially those in choline, serine and inositol glycerophospholipids. Most noticeable were the changes in phosphatidylserine; long-chain fatty acids having 20 to 22 carbon atoms and 4 to 6 double bonds decreased from about 30 to about 10 mol%. Although increased levels of saturation in other phospholipid fatty acyl chains appear to accompany the myogenic changes of BC3H-1 cells, some unsaturated fatty acids, such as oleic acid (18:1), increased by as much as 80% during the same period, suggesting the activation of a delta 9 desaturase. Sphingomyelin contained only saturated and monoenoic fatty acids and exhibited a four- to five-fold decrease in its content of monoenoic acyl groups. Diacylglycerols became enriched in arachidonate and docosahexaenoate. The amount of cholesterol and its esters increased slightly during differentiation of BC3H-1 cells. The data show that several metabolic pathways change during myogenic differentiation of the BC3H-1 clonal cell line, particularly de novo biosynthetic pathways, elongation/desaturation reactions, and acyl chain turnover.(ABSTRACT TRUNCATED AT 250 WORDS)

Extracorporeal photopheresis combined with pentostatin in the conditioning regimen for canine hematopoietic cell transplantation does not prevent GVHD.

Extracorporeal photopheresis (ECP) and the purine analog pentostatin exert potent immunomodulatory effects. We evaluated the use of these treatment modalities to prevent GVHD in a canine model of unrelated dog leukocyte Ag-mismatched hematopoietic cell transplantation, after conditioning with 920 cGy TBI. We have shown previously in this model that 36/40 dogs given MTX alone as postgrafting immunosuppression engrafted and that 25 of 40 dogs had severe GVHD and median survival of 21 days. In the current study, nine dogs received conditioning with 920 cGy TBI and postgrafting MTX either with ECP on days -2 to -1 alone (n=5) or ECP on days -6 and -5 combined with two doses of pentostatin (days -4 to -3) (n=4). Seven of nine dogs achieved engraftment. Six dogs developed severe acute GVHD (four in the group with ECP alone and two with pentostatin and ECP). We failed to demonstrate a positive impact of ECP and pentostatin for the prevention of GVHD compared with historical control dogs.

Kinetics of the PO4-P adsorption onto soils and sediments from the Mondego estuary (Portugal).

In order to assess the status of a North Atlantic Ocean Ecoregion (Mondego system, Portugal) after the implementation of a management programme, a study on PO4-P sorption was carried out. Considering that sorption velocity markedly determines the systems promptness to phosphorus external loading, the kinetics of the sorption of PO4-P onto estuarine sediments and the upstream agricultural soils was studied. The pseudo-second order kinetic equation gave an appropriate description of PO4-P sorption onto these soils and sediments, allowing for a quantitative comparison. For soils, the kinetic constants (k2*, µg(-1) g h(-1)) ranged between 0.007 and 0.017 µg(-1) g h(-1) while, in the case of sediments these ranged between 0.008 and 0.012 µg(-1) g h(-1). Results showed that the reduction of water residence time after the management action was relevant for the system status, affecting its reaction capacity to phosphorus loading.

Photodegradation of the fungicide thiram in aqueous solutions. Kinetic studies and identification of the photodegradation products by HPLC-MS/MS.

In this study, the relevance of photodegradation processes on the persistence of the fungicide thiram in waters was investigated. The photodegradation of thiram in Milli-Q water and in aqueous solutions of humic and fulvic acids, as well as the photodegradation in spiked river water were studied. Both pure thiram and one of its commercial formulations were used to prepare the solutions which were irradiated in a solar light simulator. In general, thiram photodegradation follows pseudo-first order kinetics. The half-life time of thiram 2mgL(-1) in Milli-Q water was 28min. However, the degradation rate of thiram was significantly increased (p=0.02) by the inert components of the thiram commercial formulation as well as by commercial humic acids and by fulvic acids isolated from river water (p<0.004). Thus, the half-life time of thiram decreased to 24min in the presence of the inert formulation components, while, in the presence of both humic and fulvic acids (10mgL(-1)) it decreased to 22min. Furthermore, thiram photodegradation in natural river water showed that there is a significant enhancement of the degradation rate constant of thiram relatively to Milli-Q water, corresponding to a decrease of about 38% in its half-life time. This increase of the degradation rate in river water seems to be higher than that observed in the presence of FA, suggesting that beyond organic matter, other natural river components can increase the thiram photodegradation rate. These results allow us to conclude that photodegradation by solar radiation can be an important degradation pathway of thiram in natural waters. HPLC-MS/MS allowed to identify, for the first time, three products of the photodegradation of thiram in aqueous solution. Three compounds were identified and their structure was corroborated by the MS(n) spectra fragmentation profile. Pathways for the formation of the products from thiram photodegradation are proposed and discussed.

Mosquitoes (Diptera: Culicidae) from crepuscular period in an Atlantic Forest area in Southern Brazil / Mosquitos (Diptera: Culicidae) do período crepuscular em área de Floresta Atlântica no sul do Brasil

Abstract Crepuscular period is one of the factors that may influence the biting activity of mosquitoes. Many of these insects have a peak activity in this period. The purpose of this study was to investigate the afternoon crepuscular activity of Culicidae in a remaining area of Atlantic Forest in western Santa Catarina, southern Brazil. Moreover, the possible influence of abiotic factors, the abundance and species richness were verified. In order to better analyze the influence of crepuscular period in specific composition and abundance of mosquitoes, the dusk was divided into three periods: pre-sunset, sunset and post-sunset. At the end of the study, nine hundred and eight four specimens distributed in 12 genera and 23 species were collected. Trichoprosopon pallidiventer (Lutz, 1905) (59.76%), Aedes crinifer (Theobald, 1903) (8.13%), Ae. scapularis (Rondani, 1848) (5.89%) were the most abundant species. Spring time presented the greatest abundance and species richness. During the study, among the three periods evaluated, pre-sunset had the greatest abundance and post-sunset the lowest. Pre-sunset and sunset had the greatest similarity between species. Regarding to the abiotic factors evaluated seven and 15 days before sampling, they did not present significant correlation for the three most abundant species. However, temperature had a positive correlation to these species. Moreover, the correlation between collected species and its possible role as vectors of etiological agents of diseases was discussed.

Resumo O período crepuscular é um dos fatores que pode influenciar na atividade hematofágica dos mosquitos. Muitos desses insetos iniciam ou terminam suas atividades nesse período. O objetivo deste trabalho foi estudar os Culicidae que ocorrem no crepúsculo vespertino em uma área de Floresta Atlântica no oeste de Santa Catarina, sul do Brasil. Além disso, foi analisada a possível influência de fatores abióticos, bem como abundância e riqueza de espécies. Para melhor avaliar a influência do período crepuscular na composição das espécies e na abundância destas, o crepúsculo foi dividido em três períodos: pré-crepúsculo, crepúsculo e pós-crepúsculo. Ao final do estudo foram coletados 984 exemplares distribuídos em 12 gêneros e 23 espécies. Trichoprosopon pallidiventer (Lutz, 1905) (59,76%), Aedes crinifer (Theobald, 1903) (8,13%) e Ae. scapularis (Rondani, 1848) (5,89%) foram as espécies mais abundantes. A maior abundância e riqueza de espécies se deram na primavera. Dentre os três períodos estudados, o pré-crepúsculo apresentou a maior abundância de mosquitos, em contrapartida, o pós-crepúsculo apresentou a menor abundância. Os períodos pré-crepuscular e crepuscular apresentaram maior similaridade entre si com relação à composição das espécies. Relacionando os fatores abióticos e as três espécies mais abundantes, não foi observada correlação significativa nos dados avaliados nos sete e 15 dias anteriores às coletas. Entretanto, a temperatura apresentou uma correlação positiva para estas três espécies. A relação entre as espécies coletadas e a potencial transmissão de agentes etiológicos causadores de doenças foi comentada.