Copper exposure leads to changes in chlorophyll content and secondary metabolite profile in Lantana fucata leaves.

Cultivation of plants in environments polluted by metals at toxic levels can affect the biosynthesis of secondary metabolites. Here, we analysed the effect caused by excess copper on the concentration of chlorophylls a and b and the profile of secondary metabolites of Lantana fucata leaves. Five copper (Cu) treatments (mg Cukg-1 soil) were tested: T0, 0; T1, 210; T2, 420; T3, 630; and T4, 840. We found that the concentrations of chlorophylls in the plants decreased when compared to the control. However, this did not lead to a significant reduction in its growth, possibly due to the low translocation of the metal to shoots and the activation of plant defence systems to tolerate the environment in which they are exposed, increasing the emission of lateral roots and activating pathways for the production of secondary metabolites. Therefore, we found a decrease in the concentration of two key compounds in secondary metabolism, p -coumaric and cinnamic acids in treatments with higher copper concentrations. We also found an increase in phenolics. Decreases in p -coumaric and cinnamic acids may have occurred because these are precursors in the synthesis of phenolic compounds, which are increased in the high Cu treatments. Six secondary metabolites were characterised, described for the first time for this plant species. Thus, the presence of excess Cu in the soil may have triggered an increase in the amount of reactive oxygen species in the plants, which that led to the synthesis of antioxidant compounds, as a defence strategy.

Inspiratory resistive loading after all-out exercise improves subsequent performance.

We have previously shown that post-exercise inspiratory resistive loading (IRL) reduces blood lactate ([Lac(b)(-)]). In this study, we tested the hypothesis that IRL during recovery could improve subsequent exercise performance. Eight healthy men underwent, on different days, two sequential 30-s, cycle ergometer Wingate tests. During the 10-min recovery period from test 1, subjects breathed freely or through an inspiratory resistance (15 cm H(2)O) with passive leg recovery. Arterialized [Lac(b)(-)] values, perceptual scores (Borg), cardiac output by impedance cardiography (QT), and changes in the deoxygenation status of the M. vastus lateralis by near-infrared spectroscopy (DeltaHHb), were recorded. [Lac(b)(-)] was significantly reduced after 4 min of recovery with IRL (peak [Lac(b)(-)] 12.5 +/- 2.3 mmol l(-1) with free-breathing vs. 9.8 +/- 1.5 mmol l(-1) with IRL). Effort perception was reduced during late recovery with IRL compared with free-breathing. Cardiac work was increased with IRL, since heart rate and QT were elevated during late recovery. Peripheral muscle reoxygenation, however, was significantly impaired with IRL, suggesting that post-exercise convective O(2) delivery to the lower limbs was reduced. Importantly, IRL had a dual effect on subsequent performance, i.e., improvement in peak and mean power, but increased fatigue index (P < 0.05). Our data demonstrate that IRL after a Wingate test reduces post-exercise effort perception and improves peak power on subsequent all-out maximal-intensity exercise.

Further evaluation of alternative air-filtration systems for reducing the transmission of Porcine reproductive and respiratory syndrome virus by aerosol.

The purpose of this study was to compare 4 methods for the reduction of aerosol transmission of Porcine reproductive and respiratory syndrome virus (PRRSV): high-efficiency particulate air (HEPA) filtration, 2x-low-cost filtration, bag filtration, and use of a filter tested against particles derived from dioctylphthalate (DOP). The HEPA-filtration system used a prefilter screen, a bag filter (Eurovent [EU] 8 rating), and a HEPA filter (EU13 rating). The low-cost-filtration system contained mosquito netting (prefilter), 2 fiberglass furnace filters, and 2 electrostatic furnace filters. Bag filtration involved the use of a filter rated EU8 and a minimum efficiency reporting value (MERV) of 14. The 95%-DOP, 0.3-microm-filtration system involved a pleat-in-pleat V-bank disposable filter with a 95% efficiency rating for particles 0.3 microm or greater in diameter and ratings of EU9 and MERV 15. No form of intervention was used in the control group. The experimental facilities consisted of 2 chambers connected by a 1.3-m-long duct containing the treatments. Recipient pigs, housed in chamber 2, were exposed to artificial aerosols created by a mechanically operated mister containing modified live PRRSV vaccine located in chamber 1. Aerosol transmission of PRRSV occurred in 0 of the 10 HEPA-filtration replicates, 2 of the 10 bag-filtration replicates, 4 of the 10 low-cost-filtration replicates, 0 of the 10 95%-DOP, 0.3-microm-filtration replicates, and all 10 of the control replicates. Using a similar approach, we further evaluated the HEPA- and 95%-DOP, 0.3-microm-filtration systems. Infection was not observed in any of the 76 HEPA-filtration replicates but was observed in 2 of the 76 95%-DOP, 0.3-microm replicates and 42 of the 50 control replicates. Although the difference between the 95%-DOP, 0.3-microm and control replicates was significant (P < 0.0005), so was the level of failure of the 95%-DOP, 0.3-microm system (P = 0.02). In conclusion, under the conditions of this study, some methods of air filtration were significantly better than others in reducing aerosol transmission of PRRSV, and HEPA filtration was the only system that completely prevented transmission.

Evaluation of systems for reducing the transmission of porcine reproductive and respiratory syndrome virus by aerosol.

The purpose of this study was to compare 3 methods for the reduction of aerosol transmission of Porcine reproductive and respiratory syndrome virus (PRRSV): high-efficiency particulate air (HEPA) filtration, low-cost filtration, and ultraviolet light (UV) irradiation. The HEPA-filtration system involved a pre-filter screen, a bag filter (EU8 rating), and a HEPA filter (EU13 rating). The low-cost-filtration system contained mosquito netting (pre-filter), a fiberglass furnace filter, and an electrostatic furnace filter. For UV irradiation, a lamp emitted UVC radiation at 253.7 nm. No form of intervention was used in the control group. The experimental facilities consisted of 2 chambers connected by a 1.3-m-long duct. Recipient pigs, housed in chamber 2, were exposed to artificial aerosols created by a mechanically operated mister containing modified live PRRSV vaccine located in chamber 1. Aerosol transmission of PRRSV occurred in 9 of the 10 control replicates, 8 of the 10 UVC-irradiation replicates, 4 of the 10 low-cost-filtration replicates, and 0 of the 10 HEPA-filtration replicates. When compared with no intervention, HEPA filtration and low-cost filtration significantly reduced PRRSV transmission (P < 0.0005 and = 0.0286, respectively), whereas UV irradiation had no effect (P = 0.5). However, low-cost filtration and UV irradiation were significantly less effective (P = 0.043 and P < 0.0005, respectively) than HEPA filtration. In conclusion, under the conditions of this study, HEPA filtration was significantly more effective at reducing aerosol transmission of PRRSV than the other methods evaluated.

Gammadelta lymphocyte response to porcine reproductive and respiratory syndrome virus.

Porcine reproductive and respiratory syndrome virus (PRRSV) continues to be one of the most important diseases facing swine industry today. Following PRRSV infection pigs develop both humoral and cell-mediated responses following PRRSV exposure; however, the relative importance in protection and clearance of the virus is not yet completely understood. Swine contain a large percentage of gammadelta T-lymphocytes in peripheral circulation capable of responding to various pathogens in both an innate and specific immune response. The objectives of this study were to determine whether gammadelta lymphocytes functionally respond to PRRSV upon initial exposure and re-exposure. Four month old PRRSV free gilts were intranasally inoculated with a field isolate MN-30100 then assessed at various time points post infection. On day 120, pigs were re-exposed with MN-30100 PRRSV strain and subsequently were bled on days 0, 7, and 14 post re-exposure. Lymphocyte subpopulations, antigen specific proliferation, and IFN-gamma production were evaluated throughout the study. Circulating gammadelta lymphocytes in PRRSV exposed animals expanded between days 14 to 70 (d14-d70, p = 0.016); following antigen stimulation, gammadelta lymphocyte proliferated by day 14 (d0-d14, p = 0.001) continuing through day 60. gammadelta lymphocytes produced IFN-gamma by day 14 pi continuing through day 50 (d0-d50, p = 0.004). Following re-exposure both gammadelta+ and CD4+ lymphocytes increased in IFN-gamma production. These results are not fully conclusive on the role of gammadelta lymphocytes against PRRSV; the data indicate that gammadelta lymphocytes specifically respond to PRRSV.

Evaluation of an air-filtration system for preventing aerosol transmission of Porcine reproductive and respiratory syndrome virus.

The purpose of this study was to evaluate the ability of a commercial air-filtration system to reduce aerosol transmission of Porcine reproductive and respiratory syndrome virus (PRRSV). The system consisted of a pre-filter and 2 filters with EU8 and EU13 ratings. In each of 4 trials, 5 PRRSV-infected donor pigs and 1 naive recipient pig (each 25 kg) were housed in opposing chambers connected by a 1.3-m-long duct. The system filtered air entering 1 recipient-pig chamber (filtered facility) from the donor-pig chamber but not a 2nd recipient-pig chamber (nonfiltered facility). The donor pigs had been experimentally infected with PRRSV MN-184, an isolate previously documented to be shed at a high frequency in contagious aerosols. On days 3 to 7 after infection of the donors, the 2 groups were housed in their respective chambers for 6 h and then in separate facilities, where samples were collected for testing by polymerase chain reaction and enzyme-linked immunosorbent assay over 14 d. Aerosol transmission was observed in 6 of the 20 replicates in the nonfiltered facility, whereas all pigs remained PRRSV-negative in the filtered facility; the difference was significant at P < 0.01. Thus, under the conditions of this study, the air-filtration system evaluated appeared to be highly effective at reducing aerosol transmission of PRRSV.

Virological and immunological responses to porcine reproductive and respiratory syndrome virus in a large population of gilts.

Porcine reproductive and respiratory syndrome virus (PRRSV) causes a prolonged active infection followed by a persistent infection in lymphoid tissues lasting for several months. Pigs develop both an antibody and cell-mediated immune response following PRRSV infection, but the specific role of each type in the development of protective immunity and clearance of the virus is not yet known. The aims of this study were to characterize the dynamics of PRRSV persistence from 0 to 135 d post infection (pi), characterize the kinetics of the antibody mediated immune response following PRRSV infection, and characterize the cell mediated immune responses to PRRSV infection. Eighty, 4-month-old PRRSV-free gilts were obtained from a source known to be negative for PRRSV. On day 0, gilts were infected intranasally with 10(2.4) TCID/50 MN 30-100 PRRSV. Following infection, animals were bled between days 0 to 135 pi. Viremia was detected up to day 30. Serum antibody response (by enzyme-linked immunosorbent assay [ELISA] and virus neutralization antibody) was detected from day 14 to 120 pi. Cell-mediated immune response represented by interferon gamma (IFN-gamma) was detected from day 14 to 120 pi. Persistence of PRRSV in tissues was confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) between days 30 to 135. These results indicate that serum neutralizing antibodies and IFN-gamma play an important role in the clearance of PRRSV. Nevertheless none of the parameters measured (virus neutralizing antibodies), either alone or in combination, are solely responsible for the clearance of the virus from the host and the development of sterilizing immunity.

The level of virus-specific T-cell and macrophage recruitment in porcine reproductive and respiratory syndrome virus infection in pigs is independent of virus load.

Porcine reproductive and respiratory syndrome virus (PRRSV) is the most important infectious disease agent of pigs worldwide, causing reproductive failure in pregnant sows and respiratory problems in nursing and growing pigs. PRRSV infection is characterized by a prolonged viremia of 30 or more days and an extended persistent infection of lymphoid tissues. To better understand the immunological basis for prolonged acute and persistent PRRSV infection, we have examined the cell-mediated immune (CMI) response throughout the course of infection and compared the results to the local distribution and abundance of PRRSV in infected tissues. PRRSV-specific T cells, enumerated by gamma interferon enzyme-linked immunospot assay, did not appear until 2 weeks after PRRSV inoculation, and their abundance exhibited substantial variation over time and among animals. In all cases the T-cell response was transient. High levels of viral RNA were present in lymphoid tissues of all animals in the acute phase of infection. Viral loads were decreased 1,000-fold or more in persistent infections, with the primary sites of persistence being tonsil, sternal lymph node, and inguinal lymph node. The abundance of virus-specific T cells in either acutely or persistently infected animals was highly variable and showed no correlation to the level of virus in lymphoid tissues. No significant difference in antigen-specific T-cell abundance was observed in secondary lymphoid tissues in either acute or persistent infection except for tonsil, in which the number of responding cells was extremely low. CD4(+)- and CD8(+)-T-cell frequencies did not change after PRRSV infection, though a decrease in gammadelta T cells was observed. Macrophages, the permissive cell type for PRRSV, were present in various levels in all tissue preparations and were not in proportion to local virus load. These findings indicate that a weak CMI response contributes to prolonged PRRSV infection and suggests that PRRSV suppresses T-cell recognition of infected macrophages. Thus, the slow but eventual resolution of PRRSV infection may be dependent on limiting permissive macrophages and on innate immune factors.

Assessing the duration of persistence and shedding of porcine reproductive and respiratory syndrome virus in a large population of breeding-age gilts.

Porcine reproductive and respiratory syndrome virus (PRRSV) is an RNA virus in the order Nidovirales, family Arteriviridae, genus Arterivirus. The virus induces a prolonged viremia, replicates in macrophages, and produces persistent infection. The purpose of this study was to determine if PRRSV could persist for 90 d or more in a large population of breeding-age gilts housed under environmental conditions typical of commercial swine production and to determine if experimentally infected gilts could shed virus to naive sentinel gilts beyond 90 d postinfection. Using the intranasal route, we inoculated 120 PRRSV-naïve gilts, 4 mo of age, with 5 mL of cell culture fluid containing a total dose of 10(2.4) TCID50 of a field isolate (MN-30100) of PRRSV. The index gilts were organized into 3 groups (A, B, and C), 40 gilts per group. To assess the dynamics of the experimental infection, a monitor group of 30 index gilts was blood-tested on days 0, 3, 7, 14, 30, 60, 90, 120, 150, and 180 postinfection. PRRSV viremia was detected with the polymerase chain reaction (PCR) on days 3, 7, and 14 and by virus isolation (VI) on days 7 and 14. PRRSV antibodies were detected from day 14 by enzyme-linked immunosorbent assay (ELISA). To assess shedding, 30 PRRSV-naïve sentinel gilts were commingled with the index gilts on day 90 postinfection and tested by PCR, VI, and ELISA every 15 d until 180 d postinfection; all samples were negative. To assess persistence, 40 index and 10 sentinel gilts were slaughtered at 120 (group A), 150 (group B), or 180 (group C) d postinfection. Evidence of PRRSV was not detected by PCR or VI in any tissue samples from the 120 index gilts. These results indicate that persistence and shedding of PRRSV are of short duration in breeding-age gilts.

Se debe usar siempre la nutrición perioperatoria en el cancer gástrico / We should use always in the nutrition perioperative in the gastric cancer?

La nutrición perioperatoria es discutida, ya que se ha planteado que puede aumentar las complicaciones postoperatorias. Prospectivamente se realizó un estudio de cánceres gástricos que serian operados sin complicaciones agudas. A los mismos se les dividió en 2 grupos, no al azar, uno de los cuales (PRE) recibió nutrición preoperatoria por lo menos 7 días y otro (POS), solo en el posoperatorio. Unicamente se incluyeron pacientes curados macroscopicamente de su enfermedad con la operación y sin complicaciones intra o postoperatorias inmediatas. La evaluación se realizó por parametros antropometricos y bioquímicos considerandose de mayor valor la perdida de peso y la albuminemia. La nutrición fue parenteral predominante. La morbilidad se consideró para dehiscencias (anastomotica o parietal) e infecciosas. Los resultados de la evaluación mostraron un significativo menor peso actual para el PRE (media: 50,1 kg+/-5,3; POS media: 61,6 kg +/-9,7p<0,001), presentando el 72,7 por ciento del total de los pacientes una perdida mayor del 10 por ciento. No hubo diferencias importantes entre las evaluaciones iniciales y finales de los grupos. El gasto Metabolico Basal fue de media: 1293 +/- 154; las calorías aportadas superaron ese valor en un 20 por ciento y no difirieron entre grupos. Los ingresos y egresos de Nitrogeno, tampoco fueron diferentes entre PRE y POS. La morbilidad fue de 10/33; 30, 3 por cientopara el "PRE" 3/11; 27,2 por ciento y 7/22; 31,8 por ciento para el "POS"x2=NS. La mortalidad fue de 1/33, 3,3 por ciento Una sola complicación fue imputable a la nutrición (neumotorax). La duración de la nutrición fue de media: 18+/-13 días (604 días total). El grupo "PRE" tuvo una media...

Se debe usar siempre la nutrición perioperatoria en el cancer gástrico / We should use always in the nutrition perioperative in the gastric cancer?

La nutrición perioperatoria es discutida, ya que se ha planteado que puede aumentar las complicaciones postoperatorias. Prospectivamente se realizó un estudio de cánceres gástricos que serian operados sin complicaciones agudas. A los mismos se les dividió en 2 grupos, no al azar, uno de los cuales (PRE) recibió nutrición preoperatoria por lo menos 7 días y otro (POS), solo en el posoperatorio. Unicamente se incluyeron pacientes curados macroscopicamente de su enfermedad con la operación y sin complicaciones intra o postoperatorias inmediatas. La evaluación se realizó por parametros antropometricos y bioquímicos considerandose de mayor valor la perdida de peso y la albuminemia. La nutrición fue parenteral predominante. La morbilidad se consideró para dehiscencias (anastomotica o parietal) e infecciosas. Los resultados de la evaluación mostraron un significativo menor peso actual para el PRE (media: 50,1 kg+/-5,3; POS media: 61,6 kg +/-9,7p<0,001), presentando el 72,7 por ciento del total de los pacientes una perdida mayor del 10 por ciento. No hubo diferencias importantes entre las evaluaciones iniciales y finales de los grupos. El gasto Metabolico Basal fue de media: 1293 +/- 154; las calorías aportadas superaron ese valor en un 20 por ciento y no difirieron entre grupos. Los ingresos y egresos de Nitrogeno, tampoco fueron diferentes entre PRE y POS. La morbilidad fue de 10/33; 30, 3 por cientopara el "PRE" 3/11; 27,2 por ciento y 7/22; 31,8 por ciento para el "POS"x2=NS. La mortalidad fue de 1/33, 3,3 por ciento Una sola complicación fue imputable a la nutrición (neumotorax). La duración de la nutrición fue de media: 18+/-13 días (604 días total). El grupo "PRE" tuvo una media... (AU)