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1.
J Dairy Sci ; 107(7): 4461-4475, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38331182

RESUMO

Grain mixes varying in proportions of wheat grain, barley grain, canola meal, and corn grain were fed to grazing dairy cows in early lactation to determine the contribution of canola meal and corn grain to milk yield, BW, BCS, eating behavior, and blood serum metabolite concentrations. The experiment used 80 multiparous, seasonally calving Holstein-Friesian dairy cows during the first 100 d of lactation, the treatment period, and over the subsequent carryover period of 100 d, during which all cows were fed a common diet. Cows were divided into 4 cohorts (blocks) based on calving date and within each cohort, 5 cows were randomly allocated to each of the 4 treatments. Dietary treatments included disc-milled grain mixes comprising (on a DM basis) (1) a control treatment of wheat (25%) and barley (75%); (2) wheat (25%), barley (50%), and canola meal (25%); (3) wheat (25%), barley (50%), and corn (25%), and (4) wheat (25%), barley (25%), canola meal (25%), and corn (25%). Treatment diets were introduced at 19 DIM ± 4.7 d, which included a 7-d adaptation period and were applied up until 100 DIM. Each grain mix was fed at 9 kg of DM/cow per day, offered twice daily, in equal proportions in the parlor at milking times. In addition to the grain mix, all cows grazed perennial ryegrass pasture at a daily allowance of ∼35 kg of DM/cow per day (measured to ground level). Results were analyzed in terms of corn and canola presence or absence in the diet. Including canola meal in grain mixes increased grain intake and pasture intake by 0.6 and 2.1 kg of DM/cow per day, respectively, resulting in an increased milk yield of 2.6 kg/cow per day during the first 100 d of lactation. Including canola meal also increased yields of milk fat and protein, and concentrations of milk fat, as well as increasing mean BW and BCS over the 100 d. The inclusion of canola meal in the grain mixes also resulted in greater blood serum BHB and urea concentrations, compared with feeding grain mixes that did not contain canola meal. The inclusion of corn grain provided no milk production benefits and did not change BW, BCS, or any feeding behavior variables. There were no carryover effects on milk production from either canola meal or corn grain after the treatment period. In summary, the results demonstrate that the provision of canola meal in grain mixes can improve milk production and increase mean BCS. Further, there are no benefits to milk yield when a proportion of barley is substituted for corn, in a wheat and barley grain mix fed to grazing dairy cows in early lactation. However, these results are dependent on the level of inclusion and the feeding system employed.


Assuntos
Ração Animal , Dieta , Lactação , Leite , Zea mays , Animais , Bovinos , Feminino , Leite/metabolismo , Leite/química , Dieta/veterinária , Grão Comestível
2.
J Dairy Sci ; 106(11): 7651-7660, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37641268

RESUMO

Dry matter intake (DMI) is a primary determinant of milk production in grazing dairy cows and an ability to measure the DMI of individual cows would allow herd managers to formulate supplementary rations that consider the amount of nutrients ingested from grass. The 2 related aims of this experiment were to define the mean number of swallowed boli and mass of the swallowed boli in Holstein-Friesian dairy cattle offered a variety of forages commonly fed in the dairy industry of southeastern Australia, and to evaluate 2 indirect methods for counting the number of swallows. Twelve ruminally-fistulated, lactating Holstein-Friesian cows were randomly assigned to 3 replicated 4 × 4 Latin square designs and offered 4 forages: fresh chicory (FC), fresh perennial ryegrass (RP), alfalfa hay (AH), and perennial ryegrass silage (RS). The experiment was conducted over 28 d with each of 4 periods consisting of 7 d with 3 d of measurement. Forage diets were offered to individual cows following the partial evacuation of the rumen. The first 20 min after forage was offered constituted the measurement period, during which all swallowed boli were manually captured by samplers who placed their hand through the ruminal fistula and over the cardia entrance of the rumen of each cow. Concurrently, microphones and video cameras were used for the indirect measurement of swallows. The average swallowed bolus mass overall was 17.4 g dry matter (DM) per bolus with the lowest mass observed in cows offered FC (8.9 g DM/bolus), followed by RP (14.9 g DM/bolus), compared with cows offered AH (23.6 g DM/bolus) and RS (22.3 g DM/bolus). The swallowing rate was greater in cows offered FC (78 swallows/20 min) than in cows offered RP, AH, and RS (62.3 swallows/20 min). The audio recording method showed greater concordance (Lin's concordance correlation coefficient = 0.90) with the physical capturing of the boli through the rumen, than the video recording method did (Lin's concordance correlation coefficient = 0.54). It is concluded that the mass of the swallowed boli is related to forage type and that using a microphone attached to the cow's forehead can provide an accurate measure of the number of swallows when verified against the actual number of swallows counted by manual interception of the boli at the rumen cardia.

3.
J Dairy Sci ; 104(4): 4350-4361, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33516549

RESUMO

In pasture-based dairy systems, feeding a complex concentrate mix in the parlor during milking that contains cereal grains and protein supplements has been shown to have milk production advantages over feeding straight cereal grain. This experiment had the aim of testing whether further milk production advantages could be elicited by adjusting the composition of the concentrate mix in an attempt to match the expected nutrient intake from pasture during late spring. The experiment used 96 lactating dairy cows, grazing perennial ryegrass pasture offered at a target allowance of 30 kg of dry matter/cow per day (to ground level) during late spring (mid October to November) in southeastern Australia. Cows were allocated into 3 replicates of 4 treatment groups, with 24 cows in each treatment. Each treatment group was offered 1 of 4 dietary treatments in the parlor at milking: control consisting of crushed wheat and barley grains; formulated grain mix (FGM) consisting of crushed wheat, barley, and corn grains and canola meal; designer grain mix 1 (DGM1) consisting of the same ingredients as the FGM grain mix but formulated using the CPM Dairy nutrition model to take into account the expected nutrient intake from pasture; and designer grain mix 2 (DGM2) consisting of the same ingredients as DGM1 but with canola meal replaced by urea and a fat supplement (Megalac, Volac Wilmar, Gresik, Indonesia). Concentrate mixes were offered at 8.0 kg of dry matter/cow per day, except for DGM2 cows, which were offered 7.5 kg of dry matter/cow per day. The experiment ran for a total of 28 d; after a 14-d adaptation period, nutrient intake, milk production, and body weight were measured over a 14-d measurement period. Milk yield (kg) of cows fed the FGM diet was greater than that of the control cows but was not different from that of the DGM1 and DGM2 cows. However, milk fat and protein yields (kg) were greater for cows fed the FGM diet than for all other diets. There was no difference in estimated daily pasture or total dry matter intakes between the 4 treatment groups, despite cows fed the DGM2 treatment consuming less of the concentrate mix (average 6.5 kg of dry matter/cow per day when offered 7.5 kg of dry matter/cow per day). This research has demonstrated the potential for using a nutrition model to take into account the expected nutrient intake from pasture to formulate a concentrate mix (DGM1) to achieve similar milk yields, but also highlighted the need for near real-time analyses of the pasture to be grazed so as to also capture benefits in terms of milk fat and protein yield.


Assuntos
Ração Animal , Lactação , Animais , Austrália , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Ingestão de Alimentos , Feminino , Indonésia , Leite
4.
J Dairy Sci ; 101(11): 9901-9914, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30146295

RESUMO

The effects of different wheat adaptation strategies on ruminal fluid pH, dry matter intake (DMI) and energy-corrected milk (ECM) were measured in 28 late-lactation dairy cows. Cows were fed either perennial ryegrass (PRG) hay or alfalfa hay and had no previous wheat adaptation. Wheat was gradually substituted for forage in 3 even increments, over 6 or 11 d, until wheat made up 40% of DMI (∼8 kg of dry matter/cow per day). We found no differences in DMI between adaptation strategies (6 or 11 d) within forage type; however, cows fed alfalfa hay consumed more overall and produced more ECM. The rate of ruminal pH decline after feeding, as well as the decrease in mean, minimum, and maximum ruminal pH with every additional kilogram of wheat was greater for cows fed alfalfa hay. Cows fed alfalfa hay and on the 6-d adaptation strategy had the lowest mean and minimum ruminal fluid pH on 3 consecutive days and were the only treatment group to record pH values below 6.0. Despite ruminal pH declining to levels typically considered low, no other measured parameters indicated compromised fermentation or acidosis. Rather, cows fed alfalfa hay and adapted to wheat over 6 d had greater ECM yields than cows on the 11-d strategy. This was due to the 6-d adaptation strategy increasing the metabolizable energy intake in a shorter period than the 11-d strategy, as substituting wheat for alfalfa hay caused a substantial increase in the metabolizable energy concentration of the diet. We found no difference in ECM between adaptation strategies when PRG hay was fed, as there was no difference in metabolizable energy intake. The higher metabolizable energy concentration and lower intake of the PRG hay meant the increase in metabolizable energy intake with the substitution of wheat was less pronounced for cows consuming PRG hay compared with alfalfa hay. Neither forage type nor adaptation strategy affected time spent ruminating. The higher intakes likely contributed to the lower ruminal pH values from the alfalfa hay treatments. However, both forages allowed the rumen contents to resist the large declines in ruminal pH typically seen during rapid grain adaptation. Depending on the choice of base forage, rapid grain introduction may not result in poor adaptation. In situations where high-energy grains are substituted for a low-energy, high-fiber basal forage, rapid introduction could prove beneficial over gradual strategies.


Assuntos
Ração Animal , Lactação , Leite , Rúmen/metabolismo , Triticum/metabolismo , Animais , Bovinos , Indústria de Laticínios , Grão Comestível , Metabolismo Energético , Feminino , Fermentação , Lolium , Medicago sativa , Leite/química
5.
Phytopathology ; 100(1): 33-41, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19968547

RESUMO

To understand further the role of deoxynivalenol (DON) in development of Fusarium head blight (FHB), we investigated effects of the toxin on uninfected barley tissues. Leaf segments, 1 to 1.2 cm long, partially stripped of epidermis were floated with exposed mesophyll in contact with DON solutions. In initial experiments with the leaf segments incubated in light, DON at 30 to 90 ppm turned portions of stripped tissues white after 48 to 96 h. The bleaching effect was greatly enhanced by addition of 1 to 10 mM Ca(2+), so that DON at 10 to 30 ppm turned virtually all stripped tissues white within 48 h. Content of chlorophylls a and b and of total carotenoid pigment was reduced. Loss of electrolytes and uptake of Evans blue indicated that DON had a toxic effect, damaging plasmalemmas in treated tissues before chloroplasts began to lose pigment. When incubated in the dark, leaf segments also lost electrolytes, indicating DON was toxic although the tissues remained green. Thus, loss of chlorophyll in light was due to photobleaching and was a secondary effect of DON, not required for toxicity. In contrast to bleaching effects, some DON treatments that were not toxic kept tissues green without bleaching or other signs of injury, indicating senescence was delayed compared with slow yellowing of untreated leaf segments. Cycloheximide, which like DON, inhibits protein synthesis, also bleached some tissues and delayed senescence of others. Thus, the effects of DON probably relate to its ability to inhibit protein synthesis. With respect to FHB, the results suggest DON may have multiple roles in host cells of infected head tissues, including delayed senescence in early stages of infection and contributing to bleaching and death of cells in later stages.


Assuntos
Hordeum/efeitos dos fármacos , Hordeum/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Tricotecenos/farmacologia , Antifúngicos/farmacologia , Carotenoides/metabolismo , Senescência Celular/efeitos dos fármacos , Clorofila/metabolismo , Clorofila A , Cicloeximida/farmacologia , Fusarium/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
6.
J Clin Pathol ; 59(8): 870-4, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16603645

RESUMO

BACKGROUND: The prevalence of isolated tumour cells (ITCs) in regional lymph nodes from colorectal cancer (CRC) is controversial and has never been prospectively assessed in large groups of consecutive patients. pN0 early-relapsing CRC can be explained by lymph node-ITC. AIM: To assess the prevalence of ITCs in regional lymph nodes from 309 consecutive patients with pN0M0 (pathological (p)-tumour-node-metastasis (TNM) staging system) CRCs. PATIENTS AND METHODS: ITCs were assessed by immunohistochemistry (MNF116 monoclonal antibody (1:100); Dako, Glostrup, Denmark) in two serial histological sections obtained from 5016 mesenteric lymph nodes from 309 patients with pN0 CRCs (mean number of lymph nodes per patient = 16.2; p-TNM stage 0, n = 25; p-TNM stage I, n = 123; and p-TNM stage II (A+B), n = 161). Tumour histology, vascular cancer invasion and pathological stage were also recorded. RESULTS: ITCs were detected in the regional lymph nodes of 156 of 309 (50.5%) patients with CRC, mostly in nodes located within 3 cm from the neoplasia. ITC status correlated with (a) tumour p-TNM stage (Pearson's chi(2): p<0; ordered logistic regression: odds ratio (OR) = 4.6; 95% confidence interval (CI) = 2.88 to 7.33; p<0) and (b) pT value (Pearson's chi(2): p = 0; ordered logistic regression: OR = 4.9; 95% CI = 3.1 to 7.7; p<0). By multivariate analysis, including p-TNM stage, vascular invasion and ITC status, both stage (OR = 5.1; 95% CI = 2.9 to 8.9; p<0) and vascular invasion (OR = 4.2; 95% CI = 1.94 to 8.98; p<0) were found to be independent variables associated with ITC+ lymph nodes. CONCLUSION: More than 50% of pN0-CRC patients have ITCs in the mesenteric lymph nodes. ITC status is significantly correlated with cancer stage and vascular cancer invasion. The clinicopathological effect of ITC remains to be prospectively evaluated.


Assuntos
Adenocarcinoma/secundário , Neoplasias Colorretais/patologia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Vasos Sanguíneos/patologia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Metástase Linfática , Masculino , Mesentério , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Estudos Prospectivos
7.
J Anim Sci ; 94(7): 2981-91, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27482685

RESUMO

During heat stress (HS), livestock reduce metabolic heat production by lowering activity and feed intake. Because this has obvious consequences for productivity, the aim of these experiments was to investigate nutritional methods for reducing digestive metabolic heat production, thereby allowing livestock more opportunity to dissipate excess heat. In the first experiment, the fermentation rates of corn and wheat grains were compared in an in vitro gas production system containing buffered rumen fluid. This experiment showed that corn had a slower (-15%; < 0.001) rate of gas production than wheat and no differences in total amount of gas production after 24 h of incubation. In the second experiment, we hypothesized that the lower rate of fermentation of corn would reduce metabolic heat load in wethers and, in turn, improve tolerance to HS. Twenty-two Merino × Poll Dorset wethers were housed in 2 climate-controlled rooms and were fed either corn grain plus forage (CD; 39% starch) or wheat grain plus forage (WD; 37% starch) during 3 experimental periods: period 1 (P1), which consisted of 7 d of thermoneutral conditions (18 to 21°C and 40 to 50% relative humidity [RH]) and restricted feed intake (1.3 times maintenance); period 2 (P2), which consisted of 7 d of HS (28 to 38°C and 30 to 50% RH) and restricted feed intake; and period 3 (P3), which consisted of 7 d of HS as in P2 with unrestricted feed intake (1.5 times maintenance) in a randomized control experiment. Water was offered ad libitum. The level of HS was quantified by increases in rectal temperature (RT), respiration rate (RR), and left and right flank skin temperature (LFT and RFT, respectively) and blood acid-base balance. Rectal temperature, RR, LFT, and RFT were elevated ( < 0.001) during HS, especially when wethers had unrestricted feed intake (P3). Wethers fed CD had lower RR, RT, LFT, and RFT ( < 0.001) than wethers fed WD, and this benefit was greatest during HS (P2 and P3). The reduction in RR with CD resulted in less CO exhalation (greater partial pressure of CO2) and greater HCO3 ( < 0.05) than with WD, indicating reduced efforts to dissipate heat by evaporative heat loss via panting. The greatest heat from fermentation was apparent in WD wethers, which had elevated LFT compared with RFT ( < 0.001). Crucially, this large difference was not observed with the CD wethers, indicating that the slow rate of fermentation of CD was expressed as low heat released during feed fermentation in the rumen. These data demonstrated that feeding CD may be a useful management strategy to reduce the impact of high environmental heat loads in sheep.


Assuntos
Transtornos de Estresse por Calor/veterinária , Doenças dos Ovinos/prevenção & controle , Equilíbrio Ácido-Base , Ração Animal/análise , Animais , Temperatura Corporal , Regulação da Temperatura Corporal , Digestão , Fermentação , Temperatura Alta , Masculino , Taxa Respiratória , Rúmen , Ovinos , Triticum , Zea mays
8.
J Clin Pathol ; 58(8): 805-10, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16049280

RESUMO

BACKGROUND/AIMS: In the natural history of gastric cancer, non-invasive neoplasia (NiN) precedes invasive carcinoma. A histological classification of gastric NiN has recently been proposed by a World Health Organisation international panel of experts. Genetic instability is known to be among the molecular pathways involved in gastric oncogenesis. In this retrospective cross sectional study, microsatellite instability (MSI) was analysed in a consecutive series of NiN and NiN related histological alterations from a northern Italian region at high risk for gastric cancer. PATIENTS/METHODS: Fifty five consecutive cases (indefinite for NiN, 29 cases; low grade NiN, 17 cases; high grade NiN, nine cases) were analysed by radioactive polymerase chain reaction and electrophoresis for microsatellite alterations at six loci (BAT25, BAT26, D2S123, D5S346, D17S250, and D3S1317). MSI was defined according to the Bethesda criteria distinguishing: (1) no instability in the analysed loci; (2) low frequency MSI (MSI-L); and (3) high frequency MSI (MSI-H). Immunohistochemical expression of MLH1 and MSH2 proteins was also analysed in all cases. RESULTS: Overall, MSI was found in 11 of 55 cases (indefinite for NiN, five of 29 (MSI-L, four; MSI-H, one); low grade NiN, three of 17 (MSI-L, one; MSI-H, two); high grade NiN, three of nine (MSI-L, one; MSI-H, two). CONCLUSIONS: In an Italian high risk area for gastric cancer, MSI is part of the spectrum of genetic alterations in gastric non-invasive neoplasia. In European populations at high risk of gastric cancer, DNA repair system alterations are thought to be among the early molecular events in gastric carcinogenesis.


Assuntos
Instabilidade Genômica , Repetições de Microssatélites/genética , Neoplasias Gástricas/genética , Proteínas Adaptadoras de Transdução de Sinal , Idoso , Proteínas de Transporte , Estudos Transversais , Proteínas de Ligação a DNA/metabolismo , Feminino , Infecções por Helicobacter/complicações , Helicobacter pylori , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Lesões Pré-Cancerosas/genética , Proteínas Proto-Oncogênicas/metabolismo , Estudos Retrospectivos , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia
9.
Aliment Pharmacol Ther ; 17 Suppl 2: 68-74, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12786616

RESUMO

Pathologists would claim that the most reliable information obtained on gastric diseases is pathology-based. This manuscript summarizes the four major biopsy-based contributions to the current knowledge of non-neoplastic gastric diseases: (i) the in vivo definition of gastritis; (ii) the recognition of the clinicopathological patterns of gastritis; (iii) the morphological links between gastritis and stomach cancer; and finally (iv) the recent information on the possible reversibility of early or advanced precancerous gastric lesions.


Assuntos
Biópsia/métodos , Gastropatias/patologia , Gastrite/complicações , Gastrite/patologia , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori , Humanos , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/prevenção & controle , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/etiologia
10.
AJNR Am J Neuroradiol ; 34(7): 1387-94, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23306008

RESUMO

BACKGROUND AND PURPOSE: The treatment of giant aneurysms of the vertebrobasilar junction remains a challenging task in neurosurgical practice, and the reference standard therapy is still under debate. Through a detailed postmortem study, we analyzed the hemodynamic factors underlying the formation and recanalization of an aneurysm located at this particular site and its anatomic configuration. METHODS: An adult fixed cadaveric specimen with a known VBJ GA, characterized radiographically and treated with endovascular embolization, was studied. 3D computational fluid dynamic models were built based on the specific angioarchitecture of the specimen, and each step of the endovascular treatment was simulated. RESULTS: The 3D CFD study showed an area of hemodynamic stress (high wall shear stress, high static pressure, high flow velocity) at the neck region of the aneurysm, matching the site of recanalization seen during the treatment period. CONCLUSIONS: Aneurysm morphologic features, location, and patient-specific angioarchitecture are the principal factors to be considered in the management of VBJ giant aneurysms. The 3D CFD study has suggested that, in the treatment of giant aneurysms, the intra-aneurysmal environment induced by partial coil or Onyx embolization may lead to hemodynamic stress at the neck region, potentially favoring recanalization of the aneurysm.


Assuntos
Artéria Basilar/fisiopatologia , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/fisiopatologia , Modelos Biológicos , Artéria Vertebral/fisiopatologia , Adulto , Angiografia/métodos , Angiografia Digital/métodos , Artéria Basilar/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Viscosidade Sanguínea/fisiologia , Cadáver , Simulação por Computador , Embolização Terapêutica/instrumentação , Procedimentos Endovasculares , Hemorreologia/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Recidiva , Retratamento , Stents , Estresse Mecânico , Trombose/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Resistência Vascular/fisiologia , Artéria Vertebral/diagnóstico por imagem
11.
Antonie Van Leeuwenhoek ; 63(1): 23-7, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8480989

RESUMO

Botrytis allii and Collectotrichum dematium are onion pathogens which can infect in the field and cause decay in storage. Some phenolics can hinder development of these fungi, but the effect of cytokinins is not clear. Cytokinins (kinetin or 6-benzyladenine) or phenolics (caffeic or chlorogenic acids) were added to agar at concentrations of 0 to 10(-3) M. Cultures were continuously irradiated with fluorescent light or maintained in the dark for 6 days. On unamended media, final mycelial elongation was 45 or 17.8 mm and sporulation was 28 or 10.6 x 10(4) spores/ml for Botrytis and Colletotrichum, respectively. For Botrytis, mycelial elongation was slightly (5%) but significantly increased and sporulation increased by 21% by incubation on phenolics as compared to cytokinins. Mycelial extension of Colletotrichum was not affected by amendment. Sporulation of Colletotrichum on kinetin was 16 to 28% greater than on the other amendments. As amendments concentration increased elongation of mycelia of both fungi decreased. Sporulation of Botrytis increased by 60% as amendment concentration increased from 0 to 10(-5) M and then decreased 25% at 10(-3) M. As amendment concentration increased from 0 to 10(-3) M, sporulation of Colletotrichum increased by 45%. Incubation in light increased mycelial extension 3 to 17% for Botrytis and Colletotrichum respectively, and sporulation was increased approximately 78% for both fungi. These compounds do not appear to inhibit development of these Botrytis or Colletotrichum species in culture.


Assuntos
Fungos Mitospóricos/crescimento & desenvolvimento , Meios de Cultura , Citocininas/farmacologia , Escuridão , Luz , Fungos Mitospóricos/efeitos dos fármacos , Fungos Mitospóricos/fisiologia , Fenóis/farmacologia , Plantas/microbiologia , Especificidade da Espécie , Esporos Fúngicos/fisiologia
12.
Plant Foods Hum Nutr ; 58(3): 231-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15366264

RESUMO

Beta-galactosidase and peroxidase are enzymes reported to have roles in pepper maturation. Fertilizer rate may affect activity of these enzymes in fruit maturing on the plant. Nine pepper cultivars, five non-pungent and four pungent, were fertilized at two rates in field plots in 1997 and 1998 at Lane, OK, USA. Fruit were harvested at mature green, turning, and red color developmental stages, and assayed for beta-galactosidase and peroxidase activity. Overall fruit beta-galactosidase activity increased as fertilizer rate increased, and was highest in red fruit. Fertilizer rate and fruit developmental stage did not affect peroxidase activity in 1997, but peroxidase activity was highest in red fruit in 1998. Enzyme activity appeared to be cultivar dependent, and patterns differed in both years. Activities of both enzymes were higher at the red stage in many of the non-pungent peppers than in pungent peppers. These data suggest that increased fertilizer affects the activity of at least one enzyme in fruit maturing on the plant. Cultural practices affecting enzyme activity may be used to modify concentrations of components in plants that are important for human consumption.


Assuntos
Capsicum/enzimologia , Fertilizantes/efeitos adversos , Peroxidase/efeitos dos fármacos , beta-Galactosidase/efeitos dos fármacos , Capsicum/efeitos dos fármacos , Capsicum/crescimento & desenvolvimento , Manipulação de Alimentos/métodos , Humanos , Valor Nutritivo , Peroxidase/metabolismo , Fatores de Tempo , beta-Galactosidase/metabolismo
13.
Gut ; 52(8): 1111-6, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12865267

RESUMO

BACKGROUND: The cancer risk associated with gastric non-invasive neoplasia (formerly dysplasia) is debated. This prospective long term follow up study investigates the clinicopathological behaviour of non-invasive gastric neoplasia (and related lesions), focusing on the cancer risk associated with each different histological phenotype. PATIENTS AND METHODS: A total of 118 consecutive cases (nine indefinite for non- invasive neoplasia; 90 low grade non-invasive neoplasia; 16 high grade non- invasive neoplasia; and three suspicious for invasive adenocarcinoma) with a histological follow up of more than 12 months (average 52 months; range 12-206) were prospectively followed up with a standardised protocol. Patients in whom gastric cancer was detected within 12 months from the initial diagnosis of non-invasive neoplasia were excluded, assuming that invasive carcinoma had been missed at the initial endoscopy procedure. RESULTS: Non-invasive neoplasia was no longer detectable in 57/118 cases (48%), was unchanged in 32 (30%), and evolved into gastric cancer in 20 patients (17%). Evolution to invasive adenocarcinoma was documented in both low and high grade non-invasive neoplastic lesions (8/90 low grade; 11/16 high grade) and correlated with histological severity (low versus high grade) at baseline (p<0.001). Seventy five per cent of cancers occurring during the long term follow up were stage I. CONCLUSIONS: The risk of invasive gastric cancer increases with the histological grade of the non-invasive neoplasia. Following up non-invasive gastric neoplasia increases the likelihood of gastric cancer being detected in its early stages.


Assuntos
Adenocarcinoma/patologia , Lesões Pré-Cancerosas/patologia , Neoplasias Gástricas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Progressão da Doença , Feminino , Infecções por Helicobacter/patologia , Helicobacter pylori , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos
14.
Gut ; 52(11): 1543-7, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14570720

RESUMO

BACKGROUND AND AIM: There are few data on the course of Helicobacter pylori infection in asymptomatic subjects. The aim of this study was to assess the effect of eradication therapy on the development of dyspeptic and gastro-oesophageal reflux disease in a cohort of asymptomatic individuals observed over a prolonged period. METHODS: A total of 169 blood donors infected with H pylori who had volunteered for studies on eradication in 1990 formed the cohort. To be included in this cohort subjects had to have no symptoms, as determined by a validated symptom questionnaire at the baseline visit. Eighty eight subjects were infected with H pylori while 81 had successfully undergone eradication therapy. Subjects were followed up (annually) using the same symptom questionnaire and in 2000 they underwent repeat endoscopy. RESULTS: Thirteen subjects developed symptoms during follow up. The incidence of symptoms in H pylori positive subjects was 1.893/100 person-years of follow up and in H pylori negative individuals 0.163/100 person-years of follow up. H pylori infected subjects were significantly more likely to develop symptoms (log rank test, p=0.003) as well as those infected with CagA positive strains (log rank test, p=0.017). The development of symptomatic gastro-oesophageal reflux disease was no different in individuals with and without eradication (odds ratio 0.57 (95% confidence interval 0.26-1.24); p=0.163). CONCLUSIONS: H pylori eradication prevents the development of dyspeptic symptoms and peptic ulcer disease in healthy asymptomatic blood donors and is not associated with an increase in the incidence of symptomatic gastro-oesophageal reflux disease.


Assuntos
Dispepsia/microbiologia , Refluxo Gastroesofágico/microbiologia , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Anticorpos Antibacterianos/análise , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Úlcera Duodenal/microbiologia , Duodenite/microbiologia , Endoscopia Gastrointestinal , Esofagite/microbiologia , Feminino , Gastrite/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/microbiologia , Estudos Prospectivos , Inquéritos e Questionários
15.
Mol Pathol ; 53(4): 207-10, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11040944

RESUMO

BACKGROUND: Determining both the frequency and the spectrum of p53 gene mutation in young patients with gastric cancer might provide clues to the host related genetic mechanism(s) in gastric carcinogenesis. PATIENTS AND METHODS: p53 mutations were assessed (by means of polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), followed by DNA sequencing) in a cohort of 105 consecutive Italian patients in whom gastric cancer was ascertained before the age of 41. RESULTS: A low prevalence of p53 mutations (eight of 105) was observed, with no significant difference between intestinal (three of 31; 10%) and diffuse (five of 74; 7%) phenotypes. A significantly higher prevalence of p53 mutations was associated with the cardiac location (odds ratio, 7.09; confidence interval, 1.56 to 32.11). In all but one case, p53 mutations were associated with a stage higher than I. All eight mutations were located at CpG sites, where G : C to A : T transitions have been associated with frequent methylation at the C5 position of cytosine. CONCLUSIONS: These findings show that, unlike what has been consistently demonstrated in the general population, p53 mutations are uncommon in gastric cancer occurring in young patients, and in such patients, p53 alterations are significantly associated with the cardiac location.


Assuntos
Cárdia , Genes p53 , Mutação , Neoplasias Gástricas/genética , Adolescente , Adulto , Idade de Início , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Neoplasias Gástricas/patologia
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