Modelling and visualization for the analysis and comprehension of the acoustic performance of buildings through the implementation of a building information modelling-based methodology.

Technical and technological advances have revolutionised the architecture, engineering, and construction industries in recent decades. Building information modelling (BIM) methodology has become essential in the process of information management and the development of building projects. This study aims to analyse the potential advantages of the implementation of BIM-based models for the acquisition of theoretical and procedural knowledge about building acoustics. This procedure was implemented as part of a problem-solving exercise in Science, Technology, Engineering, and Mathematics (STEM) university degrees. For this purpose, three-dimensional (3D) BIM models were generated to assess the contribution of their implementation in the process of visualization, comprehension, and analysis of the acoustic behaviour of buildings. The participants' experiences and satisfaction with the BIM models were measured through a questionnaire. The results showed a high level of satisfaction among the participants and good potential for the application of 3D models based on BIM methodology for the acquisition of knowledge and practical skills in building acoustics. These results highlight the potential of BIM models to provide information for understanding the procedure followed during data collection in the experimental analysis and to facilitate the understanding of system behavior.

Monitoring Intracellular Calcium in Response to GPCR Activation: Comparison Between Microtiter Plates and Microfluidic Assays.

Microfluidic strategies combined with transduction and electronic integration have the promise of enabling miniaturized, combinatorial assays at higher speeds and lower costs, while at the same time mimicking the local chemical concentrations and force fields of the cellular in vivo environment. In this chapter we introduce a microfluidic structure with hydrodynamic cell traps and a culture volume in the nanoliter range (50 nL), to quantitatively evaluate the transient calcium response of the endogenous Muscarinic type 1 receptor (M1) in HEK 293 T cells. The microfluidic fabrication protocol is described as well as a methodology to monitor the cell response in real time, after stimulation with M1 agonists (e.g., carbachol) and antagonists (e.g., Pirenzepine).

Influence of dietary Chlorella vulgaris and carbohydrate-active enzymes on growth performance, meat quality and lipid composition of broiler chickens.

Herein, we investigated the effect of Chlorella vulgaris as ingredient (10% of incorporation) in broiler diets, supplemented or not with 2 formulations of Carbohydrate-Active enZymes (CAZymes; Rovabio Excel AP and a mixture of recombinant CAZymes, composed by an exo-ß-glucosaminidase, an alginate lyase, a peptidoglycan N-acetylmuramic acid deacetylase and a lysozyme), on growth performance, meat quality, fatty acid composition, oxidative stability, and sensory traits. One hundred twenty 1-day-old Ross 308 male birds were randomly assigned to one of the 4 experimental diets (n = 30): corn-soybean meal-basal diet (control), basal diet with 10% C. vulgaris (CV), CV supplemented with 0.005% of a commercial CAZyme cocktail (Rovabio Excel AP), (CV + R), and CV supplemented with 0.01% of a 4-CAZyme mixture previously selected (CV + M) during the experimental period lasted from day 21 to day 35. Body weight gain and feed conversion rate of broilers were not affected by C. vulgaris but digesta viscosity increased more than 2-fold (P < 0.001) relative to the control. In addition, neither cooking loss, shear force, juiciness, flavor nor off-flavor was impaired by dietary treatments (P > 0.05). By contrast, the dietary C. vulgaris increased tenderness, yellowness (b∗) and total carotenoids in breast and thigh meats. However, no additional protective effect against lipid oxidation was observed in meat with the inclusion of microalga. Chlorella vulgaris, independently of CAZymes, had a minor impact on meat fatty acid composition but improved the proportion of some beneficial fatty acids. In summary, our data indicate a slight improvement of broiler meat quality and lipid nutritional value, without impairment of broilers' growth performance, thus supporting the usefulness of this microalga in poultry diets, up to this high level of incorporation. By contrast, the selected CAZyme mixtures used do not significantly improve the release of microalga nutrients in poultry diets, through the disruption of microalga cell wall, which warrants further research.

Diabetes consequences in the fetus liver of the non-obese diabetic mice.

DM type 1 (T1D) incidence is increasing around 3% every year and represents risks for maternal and fetal health. The objective of this study was to explore the effects of diabetes on fetus liver cells in non-obese diabetic (NOD) mice. Hyperglycemic NOD (HNOD), normoglycemic NOD (NNOD) and BALB/c females were used for mating, and the fetus livers were collected at 19.5 gestation day (gd). HNOD group had reduced fetal weight (989.5±68.32 vs 1290±57.39 mg BALB/c, P<0.05) at 19.5 gd and higher glycemia (516.66±28.86 mg dl-1, P<0.001) at both 0.5 gd and 19.5 gd compared to other groups. The protein expression of albumin (ALB) was significantly reduced in HNOD group (0.9±0.2 vs 3.36±0.36 NNOD P<0.01, vs 14.1±0.49 BALB/c P<0.001). Reduced gene expression of ALB (1.34±0.12 vs 5.53±0.89 NNOD and 5.23±0.71 BALB/c, P<0.05), Hepatic Nuclear Factor-4 alpha (HNF-4α) (0.69±0.1 vs 3.66±0.36 NNOD, P<0.05) and miR-122 (0.27±0,10 vs 0.88±0.15 NNOD, P<0.05) was present in HNOD group. No difference for alpha-Fetoprotein (AFP) and gene expression was observed. In conclusion, our findings show the impacts of T1D on the expression of ALB, AFP, HNF-4α and miR-122 in fetus liver cells by using NNOD and HNOD mice.

Diabetes consequences in the fetus liver of the non-obese diabetic mice

DM type 1 (T1D) incidence is increasing around 3% every year and represents risks for maternal and fetal health. The objective of this study was to explore the effects of diabetes on fetus liver cells in non-obese diabetic (NOD) mice. Hyperglycemic NOD (HNOD), normoglycemic NOD (NNOD) and BALB/c females were used for mating, and the fetus livers were collected at 19.5 gestation day (gd). HNOD group had reduced fetal weight (989.5 +/- 68.32 vs 1290 +/- 57.39 mg BALB/c, P < 0.05) at 19.5 gd and higher glycemia (516.66 +/- 28.86 mg dl(-1), P < 0.001) at both 0.5 gd and 19.5 gd compared to other groups. The protein expression of albumin (ALB) was significantly reduced in HNOD group (0.9 +/- 0.2 vs 3.36 +/- 0.36 NNOD P < 0.01, vs 14.1 +/- 0.49 BALB/c P < 0.001). Reduced gene expression of ALB (1.34 +/- 0.12 vs 5.53 +/- 0.89 NNOD and 5.23 +/- 0.71 BALB/c, P < 0.05), Hepatic Nuclear Factor-4 alpha (HNF-4a) (0.69 +/- 0.1 vs 3.66 +/- 0.36 NNOD, P < 0.05) and miR-122 (0.27 +/- 0,10 vs 0.88 +/- 0.15 NNOD, P < 0.05) was present in HNOD group. No difference for alpha-Fetoprotein (AFP) and gene expression was observed. In conclusion, our findings show the impacts of T1D on the expression of ALB, AFP, HNF-4a and miR-122 in fetus liver cells by using NNOD and HNOD mice.

Rat visceral yolk sac cells: viability and expression of cell markers during maternal diabetes.

The function of the visceral yolk sac (VYS) is critical for embryo organogenesis until final fetal development in rats, and can be affected by conditions such as diabetes. In view of the importance of diabetes during pregnancy for maternal and neonatal health, the objective of this study was to assess fetal weight, VYS cell markers, and viability in female Wistar rats (200-250 g) with induced diabetes (alloxan, 37 mg/kg) on the 8th gestational day (gd 8). At gd 15, rats from control (n=5) and diabetic (n=5) groups were anesthetized and laparotomized to remove the uterine horns for weighing of fetuses and collecting the VYS. Flow cytometry was used for characterizing VYS cells, and for determining mitochondrial activity, cell proliferation, DNA ploidy, cell cycle phases, and caspase-3 activity. Fetal weight was reduced in the diabetic group. Expression of the cell markers CD34, VEGFR1, CD115, CD117, CD14, CCR2, CD90, CD44, STRO-1, OCT3/4, and Nanog was detected in VYS cells in both groups. In the diabetic group, significantly decreased expression of CD34 (P<0.05), CCR2 (P<0.001), and OCT3/4 (P<0.01), and significantly increased expression of CD90 (P<0.05), CD117 (P<0.01), and CD14 (P<0.05) were observed. VYS cells with inactive mitochondria, activated caspase-3, and low proliferation were present in the rats with diabetes. Severe hyperglycemia caused by maternal diabetes had negative effects on pregnancy, VYS cell viability, and the expression of cell markers.

G protein-coupled receptors: an overview of signaling mechanisms and screening assays.

The existence of cellular receptors, a group of specialized biomolecules to which endogenous and exogenous compounds bind and exert an effect, is one of the most exciting aspects of cell biology. Among the different receptor types recognized today, G-protein-coupled receptors (GPCRs) constitute, undoubtedly, one of the most important classes, in part due to their versatility, but particularly, due to their central role in a multitude of physiological states. The unveiling of GPCR function and mode of action is a challenging task that prevails until our days, as the full potential of these receptors is far from being established. Such an undertaking calls for a joint effort of multidisciplinary teams that must combine state-of-the-art technologies with in-depth knowledge of cell biology to probe such specialized molecules. This review provides a concise coverage of the scientific progress that has been made in GPCR research to provide researchers with an updated overview of the field. A brief outline of the historical breakthroughs is followed by a discussion of GPCR signaling mechanisms and by a description of the role played by assay technologies.

Use of ImageJ to recover information from individual cells in a G protein-coupled receptor assay.

Live-cell assays used in GPCR research often rely on fluorescence techniques that generate large amounts of raw image data. Consequently, the capacity to accurately and timely extract useful information from image and video data has become more and more important. Image J is an open-source program that provides powerful tools with a simple interface designed to fit the needs of image analysis of most researchers. In this chapter, Image J routines to extract information from individual cells in a calcium GPCR assay are described. In these routines, individual cells in the same image/video data can be separated using either a progressive threshold or a local threshold method. Both methods can be optimized to either a maximum number of selection or maximum area selected resulting in conceptually distinct selections.

Ocorrência de algas cianofíticas em água de dessedentação de bovinos criados extensivamente / Occurrence of blue-green algae in the drinking water of extensively raised cattle

Na pecuária extensiva, os bebedouros naturais ou artificiais possibilitam o acesso direto dos bovinos ao seu interior e trazem como consequência a degradação da qualidade da água e o aumento dos riscos sanitários. Em tais circunstâncias ocorre a eutrofização e consequentemente a floração de algas, dentre elas cianobactérias toxigênicas. O presente estudo teve por objetivo verificar a ocorrência de cianobactérias de interesse sanitário em água de dessedentação de bovinos e descrever os seus parâmetros físico-químicos pH, temperatura e oxigênio dissolvido. Foram examinadas 19 amostras de água de cacimbas ou bebedouros naturais formados predominantemente em decorrência da precipitação pluviométrica, coletadas em seis propriedades rurais localizadas nas regiões Sudeste e Centro-Oeste, para a presença de cianobactérias e mensurados os valores de pH, temperatura e oxigênio dissolvido. Microcystis e/ou Merismopedia foram detectadas em dois bebedouros; em um dos quais havia intensa floração. Os valores de pH, temperatura e oxigênio dissolvido nas 19 coleções oscilaram entre pH 7,2-9,7, 31-34ºC e 7,8-30mg/l, respectivamente. Foram detectadas ainda algas consideradas não patogênicas de diversos gêneros, em conjunto ou não com a ocorrência das cianofíticas. Nessas condições, as práticas comuns de oferta de água de dessedentação na bovinocultura extensiva, as possibilidades de eutrofização e a contaminação por cianobactérias trazem potenciais riscos à saúde dos animais.

In extensive animal husbandry, natural or artificial ponds allow direct access of cattle to water but result in degradation of water quality and in increased health risks. Under such circumstances eutrophication occurs and consequently algal bloom, among them toxigenic cyanobacteria. The present study aimed to report the occurrence of cyanobacteria in the drinking water of cattle and to describe their physical and chemical parameters, as pH, temperature and dissolved oxygen. Nineteen samples of natural ponds or water troughs formed predominantly as result of rainfall from six farms located in the Southeast and Midwest regions of Brazil were analyzed for the presence of cyanobacteria, and pH, temperature and dissolved oxygen was measured. Microcystis and/or Merismopedia were detected in two ponds; one of them was covered with intense flowering. The values of pH, temperature and dissolved oxygen in 19 collections were pH 7.2-9.7, 31-34ºC and 7.8-30mg/l respectively. Also non-pathogenic algae of several genera were detected besides the occurrence or not of cianogenics. Under these conditions, the common practices of drinking water supply for extensively raised cattle and the possibilities of eutrophication and cyanobacterial growth bring potential risks for animal health.

Transcultural adaptation of the filial responsibility interview schedule for Brazil.

BACKGROUND: In developed countries, filial responsibility in relation to caring for elderly parents has been systematically studied. In Brazil and other developing countries, however, it is a relatively new topic and has not yet been included in the research agenda on ageing. OBJECTIVE: To describe the process of cross-cultural adaptation of the qualitative phase of the filial responsibility interview schedule into Brazilian Portuguese. METHODS: An expert committee of six team members participated in the study. In addition, individual interviews were held with 11 caregivers of older persons to evaluate the quality of the final Portuguese version of the schedule. The process included examining conceptual, item, semantic and operational equivalencies. Conceptual and item equivalencies were based on a literature review and on discussions with the expert committee. Semantic equivalence was attained through translation, back-translation, expert committee evaluation and pre-testing. The final version was pre-tested in caregivers of older persons enrolled in the home care programme of a primary health care service in Southern Brazil. RESULTS: Conceptual, item, semantic and operational equivalencies were attained. Through the interviews, responses to the open-ended questions concerning filial responsibility in the care for elderly parents pertained to the following categories: possibility of institutionalization of elderly parents, caregiver expectations, difficulties in being a child caregiver and responsibility as a natural process. CONCLUSION: The Portuguese version presented good semantic equivalence and the results showed that the concepts and items are applicable to the Brazilian context.

Action of ANP on the nongenomic dose-dependent biphasic effect of aldosterone on NHE1 in proximal S3 segment.

The rapid (2 min) nongenomic effects of aldosterone (ALDO) and/or spironolactone (MR antagonist), RU 486 (GR antagonist), atrial natriuretic peptide (ANP) and dimethyl-BAPTA (BAPTA) on the intracellular pH recovery rate (pHirr) via NHE1 (basolateral Na⁺/H⁺ exchanger isoform), after the acid load induced by NH4Cl, and on the cytosolic free calcium concentration ([Ca²âº](i)) were investigated in the proximal S3 segment isolated from rats, by the probes BCECF-AM and FLUO-4-AM, respectively. The basal pHi was 7.15±0.008 and the basal pHirr was 0.195±0.012 pH units/min (number of tubules/number of tubular areas=16/96). Our results confirmed the rapid biphasic effect of ALDO on NHE1: ALDO (10⁻¹² M) increases the pHirr to approximately 59% of control value, and ALDO (10⁻6 M) decreases it to approximately 49%. Spironolactone did not change these effects, but RU 486 inhibited the stimulatory effect and maintained the inhibitory effect. ANP (10⁻6 M) or BAPTA (5×10⁻5 M) alone had no significant effect on NHE1 but prevented both effects of ALDO on this exchanger. The basal [Ca²âº](i) was 104±3 nM (15), and ALDO (10⁻¹² or 10⁻6 M) increased the basal [Ca²âº](i) to approximately 50% or 124%, respectively. RU 486, ANP and BAPTA decreased the [Ca²âº](i) and inhibited the stimulatory effect of both doses of ALDO. The results suggest the involvement of GR on the nongenomic effects of ALDO and indicate a pHirr-regulating role for [Ca²âº](i) that is mediated by NHE1, stimulated/impaired by ALDO, and affected by ANP or BAPTA with ALDO. The observed nongenomic hormonal interaction in the S3 segment may represent a rapid and physiologically relevant regulatory mechanism in the intact animal under conditions of volume alterations.

Genomic and nongenomic stimulatory effect of aldosterone on H+-ATPase in proximal S3 segments.

The genomic and nongenomic effects of aldosterone on the intracellular pH recovery rate (pHirr) via H(+)-ATPase and on cytosolic free calcium concentration ([Ca(2+)](i)) were investigated in isolated proximal S3 segments of rats during superfusion with an Na(+)-free solution, by using the fluorescent probes BCECF-AM and FLUO-4-AM, respectively. The pHirr, after cellular acidification with a NH(4)Cl pulse, was 0.064 ± 0.003 pH units/min (n = 17/74) and was abolished with concanamycin. Aldosterone (10(-12), 10(-10), 10(-8), or 10(-6) M with 1-h or 15- or 2-min preincubation) increased the pHirr. The baseline [Ca(2+)](i) was 103 ± 2 nM (n = 58). After 1 min of aldosterone preincubation, there was a transient and dose-dependent increase in [Ca(2+)](i) and after 6-min preincubation there was a new increase in [Ca(2+)](i) that persisted after 1 h. Spironolactone [mineralocorticoid (MR) antagonist], actinomycin D, or cycloheximide did not affect the effects of aldosterone (15- or 2-min preincubation) on pHirr and on [Ca(2+)](i) but inhibited the effects of aldosterone (1-h preincubation) on these parameters. RU 486 [glucocorticoid (GR) antagonist] and dimethyl-BAPTA (Ca(2+) chelator) prevented the effect of aldosterone on both parameters. The data indicate a genomic (1 h, via MR) and a nongenomic action (15 or 2 min, probably via GR) on the H(+)-ATPase and on [Ca(2+)](i). The results are compatible with stimulation of the H(+)-ATPase by increases in [Ca(2+)](i) (at 10(-12)-10(-6) M aldosterone) and inhibition of the H(+)-ATPase by decreases in [Ca(2+)](i) (at 10(-12) or 10(-6) M aldosterone plus RU 486).

Genomic and nongenomic dose-dependent biphasic effect of aldosterone on Na+/H+ exchanger in proximal S3 segment: role of cytosolic calcium.

The effects of aldosterone on the intracellular pH recovery rate (pHirr) via Na+/H+ exchanger and on the [Ca2+]i were investigated in isolated rat S3 segment. Aldosterone [10(-12), 10(-10), or 10(-8) M with 1-h, 15- or 2-min preincubation (pi)] caused a dose-dependent increase in the pHirr, but aldosterone (10(-6) M with 1-h, 15- or 2-min pi) decreased it (these effects were prevented by HOE694 but not by S3226). After 1 min of aldosterone pi, there was a transient and dose-dependent increase of the [Ca2+]i and after 6-min pi there was a new increase of [Ca2+]i that persisted after 1 h. Spironolactone, actinomycin D, or cycloheximide did not affect the effects of aldosterone (15- or 2-min pi) but inhibited the effects of aldosterone (1-h pi) on pHirr and on [Ca2+]i. RU 486 prevented the stimulatory effect of aldosterone (10(-12) M, 15- or 2-min pi) on both parameters and maintained the inhibitory effect of aldosterone (10(-6) M, 15- or 2-min pi) on the pHirr but reversed its stimulatory effect on the [Ca2+]i to an inhibitory effect. The data indicate a genomic (1 h, via MR) and a nongenomic action (15 or 2 min, probably via GR) on [Ca2+]i and on the basolateral NHE1 and are compatible with stimulation of the NHE1 by increases in [Ca2+]i in the lower range (at 10(-12) M aldosterone) and inhibition by increases at high levels (at 10(-6) M aldosterone) or decreases in [Ca2+]i (at 10(-6) M aldosterone plus RU 486).

Esporos e toxinas de Clostridium botulinum dos tipos C e D em cacimbas no Vale do Araguaia, Goiás / Spores and toxins of Clostridium botulinum in raining ponds used as water supply for cattle in pastures in the Araguaia Valley, State of Goiás, Brazil

Foram avaliadas a ocorrência e distribuição de esporos e toxinas de Clostridium botulinum tipos C e D em 300 cacimbas empregadas como bebedouro de bovinos em 130 propriedades rurais localizadas em 12 municípios do Vale do Araguaia, Estado de Goiás. A presença de esporos foi determinada indiretamente pelo cultivo em meio de cultura, seguido da inoculação e neutralização em camundongo das amostras de sedimento do interior das cacimbas, e do solo superficial e fezes de bovinos, coletadas ao seu redor. A presença de toxina foi avaliada diretamente pela inoculação em camundongo do sedimento filtrado das cacimbas, também seguida da neutralização em camundongo com antitoxinas C e D. A presença de esporos de C. botulinum foi significativamente maior (p<0,05) nas fezes de bovinos (31 por cento), quando comparadas com os resultados das amostras de solo superficial (19 por cento) e dos sedimentos (10 por cento). Foram detectadas toxinas botulínicas dos tipos C, D, ou classificadas como pertencentes ao complexo CD, em seis amostras (2 por cento) das 300 cacimbas. Das 130 propriedades trabalhadas, em 122(93,85 por cento) foram encontrados esporos ou toxinas de Clostridium botulinum em pelo menos uma das variáveis pesquisadas, enquanto somente 8(6,15 por cento) não apresentaram qualquer contaminação A idade e profundidade das cacimbas estiveram associadas com a freqüência de detecção de esporos e toxinas. Assim, quanto mais velhas e rasas, maior a freqüência do isolamento de esporos e toxinas. A contaminação das cacimbas do Vale do Araguaia goiano com esporos e toxinas do Clostridium botulinum tipos C e D demonstra o risco potencial permanente e crescente para a ocorrência da intoxicação botulínica de origem hídrica nos bovinos.

The occurrence and distribution of Clostridium botulinum spores and toxins type C and D in 300 ponds, used by cattle for drinking on 130 farms located in 12 municipalities of the Rio Araguaia valley, State of Goiás, Brazil, was evaluated. The presence of spores was determined indirectly by cultivation in culture medium, followed by inoculation and neutralization in mice of samples of the sediment from the bottom of the raining ponds, from superficial soil and from cattle feces collected to its circuit. The toxin presence was evaluated directly by inoculation in mice of the filtered sediment of the ponds, followed by the neutralization in mice with antitoxins C and D. The presence of C. botulinum spores was significantly more frequent (p<0,05) in the cattle feces (31 percent), when compared with the results of the superficial soil samples (19 percent) and the sediments (10 percent). Botulinum toxins of type C and D or classified as belonging to the CD compound were detected in 6 samples (2 percent) of the 300 ponds. Of the 130 worked farms, in 122 (93,85 percent) ponds Clostridium botulinum spores or toxins were found in at least one of the researched variables, whilst ponds on only 8 (6,15 percent) farms did not present any contamination. Age and depth of the ponds were associated with the frequency of detection of botulinum spores and toxins. The older and shallower the ponds were, the larger was the frequency of isolation of the spores and toxins. The contamination of the ponds in the Araguaia valley with Clostridium botulinum spores and toxins type C and D demonstrates the permanent and growing potential risk for the occurrence of botulism in cattle through drinking water.

Signaling pathways in the biphasic effect of ANG II on Na+/H+ exchanger in T84 cells.

The effect of ANG II on pH(i), [Ca(2+)](i) and cell volume was investigated in T84 cells, a cell line originated from colon epithelium, using the probes BCECF-AM, Fluo 4-AM and acridine orange, respectively. The recovery rate of pH(i) via the Na(+)/H(+) exchanger was examined in the first 2 min following the acidification of pH(i) with a NH(4)Cl pulse. In the control situation, the pH(i) recovery rate was 0.118 +/- 0.001 (n = 52) pH units/min and ANG II (10(-12) M or 10(-9) M) increased this value (by 106% or 32%, respectively) but ANG II (10(-7) M) decreased it to 47%. The control [Ca(2+)](i) was 99 +/- 4 (n = 45) nM and ANG II increased this value in a dose-dependent manner. The ANG II effects on cell volume were minor and late and should not interfere in the measurements of pH(i) recovery and [Ca(2+)](i). To document the signaling pathways in the hormonal effects we used: Staurosporine (a PKC inhibitor), W13 (a calcium-dependent calmodulin antagonist), H89 (a PKA inhibitor) or Econazole (an inhibitor of cytochrome P450 epoxygenase). Our results indicate that the biphasic effect of ANG II on Na(+)/H(+) exchanger is a cAMP-independent mechanism and is the result of: 1) stimulation of the exchanger by PKC signaling pathway activation (at 10(-12) - 10(-7) M ANG II) and by increases of [Ca(2+)](i) in the lower range (at 10(-12) M ANG II) and 2) inhibition of the exchanger at high [Ca(2+)](i) levels (at 10(-9) - 10(-7) M ANG II) through cytochrome P450 epoxygenase-dependent metabolites of the arachidonic acid signaling pathway.

Effect of D-alpha-tocopherol on tubular nephron acidification by rats with induced diabetes mellitus.

The objective of the present study was to determine if treatment of diabetic rats with D-alpha-tocopherol could prevent the changes in glomerular and tubular function commonly observed in this disease. Sixty male Wistar rats divided into four groups were studied: control (C), control treated with D-alpha-tocopherol (C + T), diabetic (D), and diabetic treated with D-alpha-tocopherol (D + T). Treatment with D-alpha-tocopherol (40 mg/kg every other day, ip) was started three days after diabetes induction with streptozotocin (60 mg/kg, ip). Renal function studies and microperfusion measurements were performed 30 days after diabetes induction and the kidneys were removed for morphometric analyses. Data are reported as means +/- SEM. Glomerular filtration rate increased in D rats but decreased in D + T rats (C: 6.43 +/- 0.21; D: 7.74 +/- 0.45; D + T: 3.86 +/- 0.18 ml min-1 kg-1). Alterations of tubular acidification observed in bicarbonate absorption flux (JHCO3) and in acidification half-time (t/2) in group D were reversed in group D + T (JHCO3, C: 2.30 +/- 0.10; D: 3.28 +/- 0.22; D + T: 1.87 +/- 0.08 nmol cm-2 s-1; t/2, C: 4.75 +/- 0.20; D: 3.52 +/- 0.15; D + T: 5.92 +/- 0.19 s). Glomerular area was significantly increased in D, while D + T rats exhibited values similar to C, suggesting that the vitamin prevented the hypertrophic effect of hyperglycemia (C: 8334.21 +/- 112.05; D: 10,217.55 +/- 100.66; D + T: 8478.21 +/- 119.81 microm(2)). These results suggest that D-alpha-tocopherol is able to protect rats, at least in part, from the harmful effects of diabetes on renal function.

Effect of D-alpha-tocopherol on tubular nephron acidification by rats with induced diabetes mellitus

The objective of the present study was to determine if treatment of diabetic rats with D-alpha-tocopherol could prevent the changes in glomerular and tubular function commonly observed in this disease. Sixty male Wistar rats divided into four groups were studied: control (C), control treated with D-alpha-tocopherol (C + T), diabetic (D), and diabetic treated with D-alpha-tocopherol (D + T). Treatment with D-alpha-tocopherol (40 mg/kg every other day, ip) was started three days after diabetes induction with streptozotocin (60 mg/kg, ip). Renal function studies and microperfusion measurements were performed 30 days after diabetes induction and the kidneys were removed for morphometric analyses. Data are reported as means ± SEM. Glomerular filtration rate increased in D rats but decreased in D + T rats (C: 6.43 ± 0.21; D: 7.74 ± 0.45; D + T: 3.86 ± 0.18 ml min-1 kg-1). Alterations of tubular acidification observed in bicarbonate absorption flux (JHCO3) and in acidification half-time (t/2) in group D were reversed in group D + T (JHCO3, C: 2.30 ± 0.10; D: 3.28 ± 0.22; D + T: 1.87 ± 0.08 nmol cm-2 s-1; t/2, C: 4.75 ± 0.20; D: 3.52 ± 0.15; D + T: 5.92 ± 0.19 s). Glomerular area was significantly increased in D, while D + T rats exhibited values similar to C, suggesting that the vitamin prevented the hypertrophic effect of hyperglycemia (C: 8334.21 ± 112.05; D: 10,217.55 ± 100.66; D + T: 8478.21 ± 119.81æm²). These results suggest that D-alpha-tocopherol is able to protect rats, at least in part, from the harmful effects of diabetes on renal function.

Botulismo em bovinos de corte e leite alimentados com cama de frango / Botulism in beef and dairy cattle fed with poultry litter

Surtos de botulismo causados pelos tipos C e D da toxina botulínica são freqüentes no país, estando originalmente associados à osteofagia e à ingestão de alimentos e água contaminados. No presente trabalho são descritos os aspectos epidemiológicos, clínico-patológicos e laboratoriais de sete surtos da intoxicação em bovinos de corte e leite alimentados com cama de frango, ocorridos nos estados de São Paulo e Minas Gerais entre 1989 e 2000. Cinco surtos ocorreram em rebanhos de corte confinados ou criados extensivamente e suplementados com o subproduto, e dois em propriedades leiteiras. De um total de 1.535 animais alimentados regularmente com a cama de frango, 455 (29,64 por cento) morreram em um período que variou de 2 a 4 semanas. A morbidade nos sete surtos estudados variou de 3,47 a 100 por cento, da mesma forma que a mortalidade. Em uma das propriedades a letalidade foi de 60,52 por cento, e em todos os outros surtos ela foi acima de 88,43 por cento; em três propriedades o coeficiente foi de 100 por cento. Os sinais clínicos de paralisia progressiva, dificuldade na locomoção, decúbito e estado mental aparentemente normal, diminuição do tônus da musculatura da língua e cauda, sialorréia e dificuldade respiratória caracterizaram o quadro clínico. A necropsia de 30 animais não foi observada qualquer alteração macroscópica digna de nota. A presença de esporos de Clostridium botulinum foi detectada em amostras de cama de frango colhidas nas sete propriedades. Nas amostras de fígado, líquido ruminal e intestinal, provenientes dos 30 animais necropsiados, foi possível detectar toxinas botulínicas tipos C (5) ou D (9), ou classificada como pertencente ao complexo CD (1), em pelos menos um dos materiais provenientes de 15 animais, confirmando assim o diagnóstico clínico-patológico e epidemiológico de botulismo.

Effect of arginine vasopressin and ANP on intracellular pH and cytosolic free [Ca2+] regulation in MDCK cells.

BACKGROUND: The effects of arginine vasopressin (AVP) on intracellular pH (pHi) are not clearly defined, and may vary with cell membrane surface and the hormonal doses being studied. Since cytosolic free calcium concentration ([Ca2+]i) has an important effect on cellular H+ extrusion and it was shown that AVP increases [Ca2+]i while atrial natriuretic peptide (ANP) reduces it, there may be some interaction between AVP and ANP during the regulation of pHi. METHODS: The effects of AVP and/or ANP on pHi and [Ca2+]i were investigated in Madin-Darby canine kidney (MDCK) cells by the fluorescent probes BCECF-AM and Fluo 4-AM, respectively. The pHi recovery rate was examined in the first two minutes following the acidification of pHi with a NH4Cl pulse. RESULTS: AVP (10(-12) or 10(-9) mol/L) stimulated the rate of the Na+-dependent pHi recovery, but AVP (10(-6) mol/L) impaired it. At the apical membrane surface, specific V1 or V2 receptor antagonists did not alter the effects of AVP. At the basolateral membrane surface, the V1 antagonist returned both the stimulatory and inhibitory effects of AVP to control levels, and the V2 antagonist converted the inhibitory effect of AVP to a stimulatory effect. ANP (10(-6) mol/L) or dimethyl-BAPTA-AM (50 micromol/L) impaired both the stimulatory and inhibitory effects of AVP. AVP increased [Ca2+]i in a dose-dependent manner. ANP or dimethyl-BAPTA-AM decreased [Ca2+]i, and the subsequent addition of AVP caused only a partial recovery of [Ca2+]i. CONCLUSIONS: The results are compatible with stimulation of the Na+/H+ exchanger by increases of [Ca2+]i in the lower range (at 10(-12) or 10(-9) mol/L AVP, via basolateral V1 receptors) and inhibition at high [Ca2+]i levels (at 10(-6) mol/L AVP, via basolateral V1 and V2 receptors). ANP, by impairing the path causing the increase in [Ca2+]i, blocks both the stimulatory and inhibitory effects of AVP on Na+-dependent pHi recovery.

Interaction of angiotensin II and atrial natriuretic peptide on pH(i) regulation in MDCK cells.

The effect of ANG II and atrial natriuretic peptide (ANP) on intracellular pH (pH(i)) and cytosolic free calcium concentration ([Ca(2+)](i)) was investigated in Madin-Darby canine kidney cells by using the fluorescent probes 2', 7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein-acetoxymethyl ester (AM) and fura 2-AM or fluo 4-AM. pH(i) recovery rate was examined in the first 2 min after the acidification of pH(i) with a NH(4)Cl pulse. In the control situation, the pH(i) recovery rate was 0.088 +/- 0.014 pH units/min (n = 14); in the absence of external Na(+), this value was decreased. ANG II (10(-12) or 10(-9) M) caused an increase in this value, but ANG II (10(-7) M) decreased it. ANP (10(-6) M) or dimethyl-1,2-bis(2-aminophenoxy)ethane-N,N,N', N'-tetraacetic acid (BAPTA)-AM (50 microM) alone did not affect this value but impaired both stimulatory and inhibitory effects of ANG II. ANG II (10(-12), 10(-9), or 10(-7) M) increased [Ca(2+)](i) progressively from 99 +/- 10 (n = 20) to 234 +/- 7 mM (n = 10). ANP or dimethyl-BAPTA-AM decreases [Ca(2+)](i), and the subsequent addition of ANG II caused a recovery of [Ca(2+)](i) but without reaching ANG II values found in the absence of these agents. The results indicate a role for [Ca(2+)](i) in regulating the process of pH(i) recovery mediated by the Na(+)/H(+) exchanger, stimulated/impaired by ANG II, and not affected by ANP or ANG II plus ANP. This hormonal interaction may represent physiologically relevant regulation in conditions of volume alterations in the intact animal.