FPolymer: A Program for 3D Structure Generation and OPLS Topology of Polymers with High Molecular Mass

The need to study polymeric systems with high molecular masses by techniques such as molecular dynamics using free-use software, coupled with the difficulty of parameterizing such systems, led to the creation of the FPolymer program. This program was built in C++ language using the QT-creator framework and has a simple and intuitive interface. The main function of the program is to use previously parameterized trimers of any polymer to generate a structure with the number of repeating units indicated by the user. As output of the program, the user receives a file <file>.pdb containing the structure of the polymer and a file <file>.top with the topology prepared to perform youngest molecular dynamics in the GROMAS program. DOI: http://dx.doi.org/10.17807/orbital.v14i1.1698 &nbsp

FPolymer: A Program for 3D Structure Generation and OPLS Topology of Polymers with High Molecular Mass

The need to study polymeric systems with high molecular masses by techniques such as molecular dynamics using free-use software, coupled with the difficulty of parameterizing such systems, led to the creation of the FPolymer program. This program was built in C++ language using the QT-creator framework and has a simple and intuitive interface. The main function of the program is to use previously parameterized trimers of any polymer to generate a structure with the number of repeating units indicated by the user. As output of the program, the user receives a file .pdb containing the structure of the polymer and a file .top with the topology prepared to perform youngest molecular dynamics in the GROMAS program. DOI: http://dx.doi.org/10.17807/orbital.v14i1.1698

Blood Parameters of Lactating Cows Fed Calcium Salts as Energetic Source

Background: The negative energetic balance of lactating cows that occurs during the few weeks postpartum shifts the hormonal profile of the animal. These alterations may lead to metabolic disturbance as ketosis and lipid infiltration. Hypocalcemia is another metabolic problem that occurs in the peripartum period, it is characterized by the reduction in blood levels of calcium (Ca2+) near birth. Blood parameters illustrates the nutritional status of milking cows. The serum levels of glucose, β-hydroxybutyrate (BHB) and cholesterol are parameters that reveal liver condition and it is very important for the metabolism of milking cows. The objective of this study was to evaluate three additives in the form of a calcium salts on blood parameters of lactating cows.Materials, Methods & Results: Two Latin square 4x4 were used, whereas one comprehended of early lactation cows and the other of mid lactation cows. Animals of 2nd and 3rd parity were used only. Parity was distributed evenly among groups. The trial consisted of 4 groups with 4 treatments as follow: T1: 300 g of calcium acetate, T2: 200 g of calcium propionate, T3: 200 g of calcium salts of fatty acids, and T4: control without any calcium additive. Blood samples were collected for analysis of serial calcium, glucose, β-hydroxybutyrate (BHBA) and cholesterol. The calcium levels were higher in T1 than T3 in early lactation. There was no significant difference of glucose levels between groups. Groups T1 and T2 had lower amounts of BHBA. Cholesterol was higher in T3 and T1 in the early lactation and just in T3 was higher in the mid lactation.Discussion: Adjust the Ca2+ flow due to high feed consumption and milk production near birth is a big challenge for milking cows due to the difficulties to maintain normal serial levels of Ca2+ in the early lactation. The lower serial levels of Ca2+ in the group supplemented with calcium salts of fatty acids is due to its physical characteristics that reduces its effects on ruminal microbiota and also reduced absorption of fatty acids in intestine. The evaluation of total cholesterol can be a parameter to judge the productive capacity of milking cows, because it demonstrates the capacity of corporal fat mobilization and ingestion of energy to produce milk. An increase of total cholesterol in cows supplemented with calcium salts of fatty acids is justified by the higher intake of fatty acids in the feed containing fat, which leads to a greater lipid metabolism in blood. As the literature has limited information about calcium acetate, it is believed that the animals supplemented with calcium acetate showed higher levels of cholesterol because the acetate is converted to Acetyl coenzime A, it is the basis for cholesterol biosynthesis in lactating cows. The BHBA can be considered as an indicator of negative energetic balance due to its correlation between energetic demand and energy reserves. As propionate is produced by ruminal fermentation and is the principal source for gluconeogenesis in peripartum cows, it lowered level of BHBA in the propionate supplemented group. The acetate availability is fundamental to attend the energetic requirements of lactating cows. The acetate enters in the synthesis of fatty acids as Acetyl coenzyme-A or enters in Krebs cycle through condensation with oxaloacetate, this explains the lower serial levels of BHB in group T1. It was concluded that T1 and T2 lowered the values of BHBA in early lactation cows and the animals supplemented with calcium salts of fatty acids and calcium acetate shower higher levels of cholesterol in early lactation and the T3 group in the mid lactation

Effects of ovariectomy and resistance training on oxidative stress markers in the rat liver

OBJECTIVE: The objective of this study was to assess the effects of resistance training on oxidative stress markers in the livers of ovariectomized rats. METHOD: Adult Sprague-Dawley rats were divided into the following four groups (n = 8 per group): sham-operated sedentary, ovariectomized sedentary, sham-operated resistance training, and ovariectomized resistance training. During the resistance training period, the animals climbed a 1.1-m vertical ladder with weights attached to their tails; the sessions were conducted 3 times per week, with 4-9 climbs and 8-12 dynamic movements per climb. The oxidative stress was assessed by measuring the levels of reduced glutathione and oxidized glutathione, the enzymatic activity of catalase and superoxide dismutase, lipid peroxidation, vitamin E concentrations, and the gene expression of glutathione peroxidase. RESULTS: The results showed significant reductions in the reduced glutathione/oxidized glutathione ratio (4.11±0.65 nmol/g tec), vitamin E concentration (55.36±11.11 nmol/g), and gene expression of glutathione peroxidase (0.49±0.16 arbitrary units) in the livers of ovariectomized rats compared with the livers of unovariectomized animals (5.71±0.71 nmol/g tec, 100.14±10.99 nmol/g, and 1.09±0.54 arbitrary units, respectively). Moreover, resistance training for 10 weeks was not able to reduce the oxidative stress in the livers of ovariectomized rats and induced negative changes in the hepatic anti-oxidative/oxidative balance. CONCLUSION: Our findings indicate that the resistance training program used in this study was not able to attenuate the hepatic oxidative damage caused by ovariectomy and increased the hepatic oxidative stress

Calcium Propionate Increased Milk Parameters in Holstein Cows

Background: In the early lactation, dairy cows go through a period of negative energy balance because they do not intake enough food to supply the energetic demand of milk production. In this period, dairy cows are susceptible to metabolic disorders, although has little evidence that milk production contribute to increase diseases occurrence. Some alternatives to minimize metabolic disorders, that reduce milk yield, has been suggested, as increase energy density in the diet of dry cows 21 days before the parturition and include additives in the diet pre and post-partum. The aim of this study was to measure the productive parameters in dairy cows fed calcium salts as energetic source.           Materials, Methods & Results: Two Latin square 4x4 were used, whereas one comprehended of early lactation cows and the other of mid lactation cows. Animals of 2nd and 3rd parity were used only. Parity was distributed evenly among groups. The trial consisted of 4 groups with 4 treatments as follow: T1: 300 g of calcium acetate, T2: 200 g of calcium propionate, T3: 200 g of calcium salts of fatty acids, and T4: control without any calcium additive. The animals were milked twice a day, the first milking at 07:00 am and the second milking at 05:00 pm. Milk samples were collected in plastic containers with potassium dichromate. These samples were sent to the Laboratory of Milk Analysis of the Paranaense Association of Breeders of the Holstein Breed for analysis of fat, protein, lactose and total solids through the infrared method. Throughout the experimental period, the daily production of the animals under study was recorded. The production of milk (kg) was corrected to 3.5% fat using the formula PLA 3.5% = (0.432 + kg milk) + (0.1623 x kg milk x fat content).Discussion: Greater supply of glucose or propionate stimulate milk protein production, but the mechanism of this stimulation is unclear. Milk protein is dependent on energy supply, and deficient energy intake reduces milk protein levels. Calcium propionate provided enough energy supply and increased milk protein levels. The synthesis of lactose has influence in water absorption in mammary gland and lactose determine milk osmolarity. The lactose levels vary according blood glucose, somatic cells count and energy availability for physiological processes. In the literature, rarely has been found greater lactose concentration caused by feed intake, becoming very important the results found in this work. The diet energy concentration and consumption rate determine energy intake, which limit milk yield. Dairy cows in early lactation has marked increased of nutrient requirements to support milk production. Support milk lactose synthesis in the mammary gland is the one of responsible for increase of nutrients requirements. In this period, the glucose demands increases 2 times more than during late gestation. Propionate is converted to glucose in the liver and it will be support lactose synthesis in the mammary gland. Propionate supplementation in this work provided better energetic supply and it is possible to consider, evaluating the milk yield. It was concluded that calcium propionate increased milk parameters like: milk protein, lactose and milk fat. Holstein cows fed calcium propionate had greater milk yield than other groups

Blood Parameters of Lactating Cows Fed Calcium Salts as Energetic Source

Background: The negative energetic balance of lactating cows that occurs during the few weeks postpartum shifts the hormonal profile of the animal. These alterations may lead to metabolic disturbance as ketosis and lipid infiltration. Hypocalcemia is another metabolic problem that occurs in the peripartum period, it is characterized by the reduction in blood levels of calcium (Ca2+) near birth. Blood parameters illustrates the nutritional status of milking cows. The serum levels of glucose, β-hydroxybutyrate (BHB) and cholesterol are parameters that reveal liver condition and it is very important for the metabolism of milking cows. The objective of this study was to evaluate three additives in the form of a calcium salts on blood parameters of lactating cows.Materials, Methods & Results: Two Latin square 4x4 were used, whereas one comprehended of early lactation cows and the other of mid lactation cows. Animals of 2nd and 3rd parity were used only. Parity was distributed evenly among groups. The trial consisted of 4 groups with 4 treatments as follow: T1: 300 g of calcium acetate, T2: 200 g of calcium propionate, T3: 200 g of calcium salts of fatty acids, and T4: control without any calcium additive. Blood samples were collected for analysis of serial calcium, glucose, β-hydroxybutyrate (BHBA) and cholesterol. The calcium levels were higher in T1 than T3 in early lactation. There was no significant difference of glucose levels between groups. Groups T1 and T2 had lower amounts of BHBA. Cholesterol was higher in T3 and T1 in the early lactation and just in T3 was higher in the mid lactation.Discussion: Adjust the Ca2+ flow due to high feed consumption and milk production near birth is a big challenge for milking cows due to the difficulties to maintain normal serial levels of Ca2+ in the early lactation. The lower serial levels of Ca2+ in the group supplemented with calcium salts of fatty acids is due to its physical characteristics that reduces its effects on ruminal microbiota and also reduced absorption of fatty acids in intestine. The evaluation of total cholesterol can be a parameter to judge the productive capacity of milking cows, because it demonstrates the capacity of corporal fat mobilization and ingestion of energy to produce milk. An increase of total cholesterol in cows supplemented with calcium salts of fatty acids is justified by the higher intake of fatty acids in the feed containing fat, which leads to a greater lipid metabolism in blood. As the literature has limited information about calcium acetate, it is believed that the animals supplemented with calcium acetate showed higher levels of cholesterol because the acetate is converted to Acetyl coenzime A, it is the basis for cholesterol biosynthesis in lactating cows. The BHBA can be considered as an indicator of negative energetic balance due to its correlation between energetic demand and energy reserves. As propionate is produced by ruminal fermentation and is the principal source for gluconeogenesis in peripartum cows, it lowered level of BHBA in the propionate supplemented group. The acetate availability is fundamental to attend the energetic requirements of lactating cows. The acetate enters in the synthesis of fatty acids as Acetyl coenzyme-A or enters in Krebs cycle through condensation with oxaloacetate, this explains the lower serial levels of BHB in group T1. It was concluded that T1 and T2 lowered the values of BHBA in early lactation cows and the animals supplemented with calcium salts of fatty acids and calcium acetate shower higher levels of cholesterol in early lactation and the T3 group in the mid lactation

Effects of ovariectomy and resistance training on oxidative stress markers in the rat liver

OBJECTIVE: The objective of this study was to assess the effects of resistance training on oxidative stress markers in the livers of ovariectomized rats. METHOD: Adult Sprague-Dawley rats were divided into the following four groups (n = 8 per group): sham-operated sedentary, ovariectomized sedentary, sham-operated resistance training, and ovariectomized resistance training. During the resistance training period, the animals climbed a 1.1-m vertical ladder with weights attached to their tails; the sessions were conducted 3 times per week, with 4-9 climbs and 8-12 dynamic movements per climb. The oxidative stress was assessed by measuring the levels of reduced glutathione and oxidized glutathione, the enzymatic activity of catalase and superoxide dismutase, lipid peroxidation, vitamin E concentrations, and the gene expression of glutathione peroxidase. RESULTS: The results showed significant reductions in the reduced glutathione/oxidized glutathione ratio (4.11±0.65 nmol/g tec), vitamin E concentration (55.36±11.11 nmol/g), and gene expression of glutathione peroxidase (0.49±0.16 arbitrary units) in the livers of ovariectomized rats compared with the livers of unovariectomized animals (5.71±0.71 nmol/g tec, 100.14±10.99 nmol/g, and 1.09±0.54 arbitrary units, respectively). Moreover, resistance training for 10 weeks was not able to reduce the oxidative stress in the livers of ovariectomized rats and induced negative changes in the hepatic anti-oxidative/oxidative balance. CONCLUSION: Our findings indicate that the resistance training program used in this study was not able to attenuate the hepatic oxidative damage caused by ovariectomy and increased the hepatic oxidative stress