RESUMO

Risk factors that determine the severity of Covid-19 have not been fully elucidated. The aim of this study was to evaluate the role of coronary artery calcification (CAC) as a risk factor for death or mechanical ventilation (MV) of patients without known heart disease infected with Covid-19. We analyzed 283 consecutive in-patients with acute respiratory symptoms with chest computed tomography (chest-CT), without previous heart disease, and criteria for Covid-19 (RT-PCR positive and/or typical clinical and chest-CT findings). CAC was classified by the number of coronary segments affected as absent (0), mild (1-3), and severe calcification (more than 3). The association between CAC, CAC severity, and death or MV due to severe respiratory failure was assessed by logistic regression. The mean age was 58.7±15.7 years and 54.1% were men. Patients with CAC were older, more likely to have hypertension, and less likely to be obese. CAC was present in 75 patients (26.5%), of which 42 had a mild calcification and 33 had severe calcification, and was associated with death (OR=2.35, 95%CI: 1.01-5.48) or MV (OR=2.72, 95%CI: 1.20-6.20) adjusted for multiple confounders, with significant and increased odds ratio for the severe form of CAC (death: OR=3.70, 95%CI: 1.20-11.42; MV: OR=3.30, 95%CI: 1.09-9.95). We concluded that CAC was an independent risk factor for death or MV in Covid-19 patients without previous heart disease, particularly for those with severe calcification. CAC can be easily visualized on common chest-CT, widely used in evaluation of moderate to severe Covid-19.

Assuntos

RESUMO

Risk factors that determine the severity of Covid-19 have not been fully elucidated. The aim of this study was to evaluate the role of coronary artery calcification (CAC) as a risk factor for death or mechanical ventilation (MV) of patients without known heart disease infected with Covid-19. We analyzed 283 consecutive in-patients with acute respiratory symptoms with chest computed tomography (chest-CT), without previous heart disease, and criteria for Covid-19 (RT-PCR positive and/or typical clinical and chest-CT findings). CAC was classified by the number of coronary segments affected as absent (0), mild (1-3), and severe calcification (more than 3). The association between CAC, CAC severity, and death or MV due to severe respiratory failure was assessed by logistic regression. The mean age was 58.7±15.7 years and 54.1% were men. Patients with CAC were older, more likely to have hypertension, and less likely to be obese. CAC was present in 75 patients (26.5%), of which 42 had a mild calcification and 33 had severe calcification, and was associated with death (OR=2.35, 95%CI: 1.01-5.48) or MV (OR=2.72, 95%CI: 1.20-6.20) adjusted for multiple confounders, with significant and increased odds ratio for the severe form of CAC (death: OR=3.70, 95%CI: 1.20-11.42; MV: OR=3.30, 95%CI: 1.09-9.95). We concluded that CAC was an independent risk factor for death or MV in Covid-19 patients without previous heart disease, particularly for those with severe calcification. CAC can be easily visualized on common chest-CT, widely used in evaluation of moderate to severe Covid-19.

Assuntos

RESUMO

The influence of Toxoplasma gondii on semen variables and sperm morphology of sheep was evaluated in eight reproductive males distributed into three experimental groups: GI, three sheep inoculated with 2.0x10(5) of P strain oocytes; GII, three sheep infected with 1.0x10(6) of RH strain tachyzoites and; GIII two control sheep. Clinical (rectal temperature, cardiac and respiratory frequencies), parasite and serology exams (IIF) were realized. Sperm variables (volume, motility, vigor and concentration) and semen morphology for each sheep were also evaluated. Thus, semen and blood collections were assessed on post-inoculation days (PIDs)-1,3,5,7,11,14 and weekly thereafter up to PID 70. Clinical alterations were observed (hypothermia and anorexia) in infected sheep from groups GI and GII. Parasitic outbreaks were detected in five sheep. All the infected sheep produced antibodies against T. gondii from PID 5 onwards, reaching a peak of 4096 and 8192 for group GI and GII sheep, respectively. Differences (P<0.05) were observed regarding the ejaculate volume between the inoculated groups (oocytes and tachyzoites) and control. Even though experimental toxoplasmic infection resulted in clinical symptomology in the inoculated sheep, the minimal alterations in sperm pathologies could not be directly attributed to T. gondii.

Assuntos

RESUMO

The human populations of the Brazilian Amazon were formed by interethnic crosses between Europeans, Africans, and Amerindians. The relative contribution of men and women of different ethnic groups was not homogeneous, since the social policies of the first three centuries of Brazilian colonization encouraged mating between European men and indigenous women and, later on, African women. In order to test this model based on historical data, we compared the relative contribution of the Y-DNA and mtDNA of Amerindian and non-Amerindian populations to the formation of the urban population of the town of Belém, in the Amazon region, on the basis of a C-->T mutation at locus DYS199 present in 90% of the Amerindian Y-DNA and of five markers that define 99% of the mitochondrial sequences of Amerindians. The contribution of indigenous men to the formation of this population was less than 5%, whereas the contribution of indigenous women was estimated at more than 50% of the mitochondrial sequences of the same population. Thus, the present results demonstrate that the contribution of indigenous women to the formation of the Belém population was 10 times higher than the contribution of indigenous men, a genetic consequence of social behavior and attitudes of the past; our results also help clarify the process of integration of indigenous communities into the urban societies in Brazil and possibly in other countries.

Assuntos

RESUMO

With the objective of studying the effects of foliar application of uniconazole (S-3307D) on soybean plants (Glycine max (L.) Merrill cv IAC-17), at the beginning of the flowering stage, a field experiment was carried out using uniconazole at the following doses: 2.5; 5.0; 10.0 e 20.0 g a.i./ha. The experimental design consisted of randomized blocks with 5 treatments and 4 replicates; plot size was 10 m2, and the total experimental area 800 m2. The effects of S-3307D on the productivity of soybean plants were evaluated through the following observations, made at harvesting: weight in Kg of plants per 10 m2, number of plants per 10 m2, number of pods per plant, number of seeds per pod, weight of 100 seeds (in grams), height of the plants (in cm) and number of branches. According to the results, it can be concluded that uniconazole at 10.0 g a.i./ha was efficient for increasing the yield of soybean (Glycine max (L.) Merrill cv IAC-17).

O presente trabalho foi conduzido no campo com o objetivo de estudar os efeitos da aplicação foliar de uniconazole (S-3307D) no início da floração em plantas de soja (Glycine max (L.) Merrill cv IAC-17). As dosagens de uniconazole utilizadas foram: 2,5; 5,0; 10,0 e 20,0 g i.a./ha. O delineamento experimental utilizado foi de blocos ao acaso, com 5 tratamentos contendo 4 repetições cada, sendo o tamanho de cada parcela de 40 m2, totalizando 800 m2 de área experimental. Para a avaliação dos efeitos do S-3307D sobre a produtividade de plantas de soja, foram realizadas as seguintes observações, no momento da colheita: produção (peso em Kg das plantas em 10 m2); número de plantas/10 m2; número de vagens/planta; número de grãos/vagem; peso de 100 grãos (em g); altura da planta (em cm) e número de ramos. A partir dos resultados obtidos pode-se concluir que uniconazole a 10,0 g i.a./ha, foi eficiente em aumentar a produtividade da cultura de soja (Glycine max (L.) Merrill cv IAC-17).

RESUMO

With the objective of studying the effects of foliar application of uniconazole (S-3307D) on soybean plants (Glycine max (L.) Merrill cv IAC-17), at the beginning of the flowering stage, a field experiment was carried out using uniconazole at the following doses: 2.5; 5.0; 10.0 e 20.0 g a.i./ha. The experimental design consisted of randomized blocks with 5 treatments and 4 replicates; plot size was 10 m2, and the total experimental area 800 m2. The effects of S-3307D on the productivity of soybean plants were evaluated through the following observations, made at harvesting: weight in Kg of plants per 10 m2, number of plants per 10 m2, number of pods per plant, number of seeds per pod, weight of 100 seeds (in grams), height of the plants (in cm) and number of branches. According to the results, it can be concluded that uniconazole at 10.0 g a.i./ha was efficient for increasing the yield of soybean (Glycine max (L.) Merrill cv IAC-17).

O presente trabalho foi conduzido no campo com o objetivo de estudar os efeitos da aplicação foliar de uniconazole (S-3307D) no início da floração em plantas de soja (Glycine max (L.) Merrill cv IAC-17). As dosagens de uniconazole utilizadas foram: 2,5; 5,0; 10,0 e 20,0 g i.a./ha. O delineamento experimental utilizado foi de blocos ao acaso, com 5 tratamentos contendo 4 repetições cada, sendo o tamanho de cada parcela de 40 m2, totalizando 800 m2 de área experimental. Para a avaliação dos efeitos do S-3307D sobre a produtividade de plantas de soja, foram realizadas as seguintes observações, no momento da colheita: produção (peso em Kg das plantas em 10 m2); número de plantas/10 m2; número de vagens/planta; número de grãos/vagem; peso de 100 grãos (em g); altura da planta (em cm) e número de ramos. A partir dos resultados obtidos pode-se concluir que uniconazole a 10,0 g i.a./ha, foi eficiente em aumentar a produtividade da cultura de soja (Glycine max (L.) Merrill cv IAC-17).

RESUMO

The effect of magnesium levels in nutrient solution upon plant height, number of leaves and fruits, and leaf area of common bean was studied. Bean plants (3 per pot) were grown in 6 l pots containing Hoagland & Arnon n. 2 solution, modified for the magnesium concentration. The experimental design was a completely randomized factorial, replicated 3 times, with 5 magnesium levels, and 5 samplings which were done fortnightly. The number of leaves and the leaf area in the 3rd and 4th samplings were increased when the 2.4 ppm magnesium level was employed. Height and number of leaves in the 3rd sampling were increased when the plants were submitted to 24.3 ppm. On the other hand, an increased number of leaves was observed in the 3rd sampling when 72.9 ppm was used. When 97.2 ppm of magnesium was employed, there was an increase in the number of leaves at the 3rd and 5th samplings. Therefore, it can be suggested that, 2,4 ppm of magnesium is sufficient to maintain adequate development of the common bean. These results also suggest that, for the growth and development of the common bean the ideal level of magnesium is between 2.4 and 24.3 ppm.

O presente estudo teve como objetivo avaliar a influência dos níveis de magnésio sobre a altura, número de folhas e frutos e área foliar do feijoeiro (Phaseolus vulgaris L. cv Carioca), que constituem seus parâmetros biométricos. Empregou-se a solução nutritiva nº 2 de Hoagland & Arnon, modificada pela variação da concentração desse mineral, que estabeleceu a diferença entre os tratamentos. Em cada vaso, com capacidade para 6 litros, foram cultivadas 3 plantas. O experimento foi inteiramente casualizado, com 3 repetições, em esquema fatorial, com 5 níveis de magnésio e 5 colheitas, realizadas a intervalos de 14 dias. As plantas apresentaram aumento do número de folhas e da área foliar, na 3ª e 4ª colheitas, quando nutridas com 2,4 ppm de magnésio e aumento de altura e número de folhas, na 3ª colheita, naquelas submetidas a 24,3 ppm. Aumento do número de folhas, na 3ª colheita, foi observado em plantas nutridas com 72,9 ppm e na 3ª e 5ª colheitas naquelas submetidas a 97,2 ppm. Estes resultados sugerem que, nas condições do experimento, 2,4 ppm de Mg foram suficientes para manter o desenvolvimento adequado dos feijoeiros e que o nível ideal deste mineral para crescimento e desenvolvimento das plantas estaria entre 2,4 e 24,3 ppm.

RESUMO

The effects of gibberellins, cytokinins and potassium nitrate on the development of `Rangpur'lime (Citrus limonia Osbeck) rootstocks were studied. Seeds from ripe fruits were washed, dried and stored at 4 - 5o C for 60 days. They were planted in nursery plots in May/1993 and when the seedlings had 10 - 20 cm height, they were transplanted to a second nursery stage. The seedlings were sprayed at 15-day intervals, with plant regulators and potassium nitrate, after reaching the age of 8 months. From January to March/1993, the seedlings were sprayed with: 25, 50 and 75 ppm of GA3; 25, 50 and 75 ppm of GA4+7 + phenylmethyl-aminepurine; 20 ppm of phenylmethylpyranil-aminepurine; 0.2% of KNO3. The seedlings planted in May/1993 did not reach earlier suitable size for budding when compared to the control. The treatments with KNO3 0.2% showed a tendency to inhibit the seedling growth.

Os efeitos de reguladores vegetais do grupo das giberelinas e citocininas, bem como do nitrato de potássio, foram estudados no crescimento e desenvolvimento do porta-enxerto de limoeiro `Cravo' (Citrus limonia Osbeck). As sementes foram extraídas de frutos maduros, lavadas, secas à sombra e armazenadas em câmara fria (4 - 5oC) durante sessenta dias, até o mês de maio/1993, quando foram semeadas nos canteiros de semeadura. As pulverizações com os fitorreguladores foram realizadas no viveiro e tiveram início com as plantas aos 8 meses de idade, contados a partir da semeadura, sendo efetuadas um total de 4 pulverizações, realizadas a intervalos quinzenais. Os tratamentos corresponderam a: 25, 50 e 75 ppm de GA3; 25, 50 e 75 ppm de GA4+GA7+fenilmetil-aminopurina; 20 ppm de fenilmetilpiranil-aminopurina; 0,2% de KNO3 e testemunha (sem pulverização). Os resultados obtidos permitiram concluir que as pulverizações com os reguladores vegetais e com o nitrato de potássio, realizadas no período de janeiro a março (verão), não tiveram efeito na diminuição do tempo de formação das plantas jovens de limoeiro `Cravo', tendo inclusive, o tratamento com KNO3 0,2%, exercido efeito depressivo no desenvolvimento das mesmas.

RESUMO

The effects of a plant regulator were studied for rangpur lime seedlings sprayed at 14-day intervals, from the 70th day until the 210th. The seedlings were sprayed with: T1 = 0; T2 = 25; T3 = 50; T4 = 100; T5 = 150 ppm of gibberellic acid. The applications of gibberellic acid on the seedlings of rangpur lime rootstocks resulted in significant increases in plant height (T5 = 150 ppm) and stem diameter (T2 = 25 ppm and T3 = 50 ppm). The seedlings reached the buddable size in shorter time through the positive effects of the plant regulator. The stem diameter was higher with gibberellic acid at concentrations of 25 and 50 ppm. Shortening this time would benefit nurserymen by reducing various production inputs and costs.

O presente trabalho foi instalado em condições de campo com plântulas de limão `Cravo'(Citrus limonia Osbeck), em delineamento inteiramente casualizado, com três repetições no esquema de parcelas sub-divididas, onde os tratamentos principais foram 5 concentrações de ácido giberélico: T1 = 0, T2 = 25, T3 = 50, T4 = 100 e T5 = 150 ppm, parceladas em quatro pulverizações. Os tratamentos secundários foram as coletas do material, realizadas dos 70 aos 210 dias, em intervalos de 14 dias. Pelos resultados obtidos, o fitorregulador promoveu efeito favorável com relação ao incremento do comprimento do caule, sendo o tratamento de 150 ppm superior aos demais. O diâmetro do caule atingiu maiores dimensões com aplicação de ácido giberélico 50 e 25 ppm.

RESUMO

The effects of a plant regulator were studied for rangpur lime seedlings sprayed at 14-day intervals, from the 70th day until the 210th. The seedlings were sprayed with: T1 = 0; T2 = 25; T3 = 50; T4 = 100; T5 = 150 ppm of gibberellic acid. The applications of gibberellic acid on the seedlings of rangpur lime rootstocks resulted in significant increases in plant height (T5 = 150 ppm) and stem diameter (T2 = 25 ppm and T3 = 50 ppm). The seedlings reached the buddable size in shorter time through the positive effects of the plant regulator. The stem diameter was higher with gibberellic acid at concentrations of 25 and 50 ppm. Shortening this time would benefit nurserymen by reducing various production inputs and costs.

O presente trabalho foi instalado em condições de campo com plântulas de limão `Cravo'(Citrus limonia Osbeck), em delineamento inteiramente casualizado, com três repetições no esquema de parcelas sub-divididas, onde os tratamentos principais foram 5 concentrações de ácido giberélico: T1 = 0, T2 = 25, T3 = 50, T4 = 100 e T5 = 150 ppm, parceladas em quatro pulverizações. Os tratamentos secundários foram as coletas do material, realizadas dos 70 aos 210 dias, em intervalos de 14 dias. Pelos resultados obtidos, o fitorregulador promoveu efeito favorável com relação ao incremento do comprimento do caule, sendo o tratamento de 150 ppm superior aos demais. O diâmetro do caule atingiu maiores dimensões com aplicação de ácido giberélico 50 e 25 ppm.