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Journal of Dairy Science Dec 2021Our objective was to determine the effects of temperature and protein concentration on viscosity increase and gelation of liquid micellar casein concentrate (MCC) at...
Our objective was to determine the effects of temperature and protein concentration on viscosity increase and gelation of liquid micellar casein concentrate (MCC) at protein concentrations from 6 to 20% during refrigerated storage. Skim milk (∼350 kg) was pasteurized (72°C for 16 s) and filtered through a ceramic microfiltration system to make MCC and replicated 3 times. The liquid MCC was immediately concentrated via a plate ultrafiltration system to 18% protein (wt/wt). The MCC was then diluted to various protein concentrations (6-18%, wt/wt). The highest protein concentrations of MCC formed gels almost immediately on cooling to 4°C, whereas lower concentrations of MCC were viscous liquids. Apparent viscosity (AV) determination using a rotational viscometer, gel strength using a compression test, and protein analysis of supernatants from ultracentrifugation by the Kjeldahl method were performed. The AV data were collected from MCC (6.54, 8.75, 10.66, and 13.21% protein) at 4, 20, and 37°C, and compression force test data were collected for MCC (15.6, 17.9, and 20.3% protein) over a period of 2-wk storage at 4°C. The maximum compressive load was compared at each time point to determine the changes in gel strength over time. Supernatants from MCC of 6.96 and 11.61% protein were collected after ultracentrifugation (100,605 × g for 2 h at 4, 20, and 37°C) and the nitrogen distributions (total, noncasein, casein, and nonprotein nitrogen) were determined. The protein and casein as a percent of true protein concentration in the liquid phase around casein micelles in MCC increased with increasing total MCC protein concentration and with decreasing temperature. Casein as a percent of true protein at 4°C in the liquid phase around casein micelles increased from about 16% for skim milk to about 78% for an MCC containing 11.6% protein. This increase was larger than expected, and this may promote increased viscosity. The AV of MCC solutions in the range of 6 to 13% casein increased with increasing casein concentration and decreasing temperature. We observed a temperature by protein concentration interaction, with AV increasing more rapidly with decreasing temperature at high protein concentration. The increase in AV with decreasing temperature may be due to the increase in protein concentration in the aqueous phase around the casein micelles. The MCC containing about 16 and 18% casein gelled upon cooling to form a gel that was likely a particle jamming gel. These gels increased in strength over 10 d of storage at 4°C, likely due either to the migration of casein (CN) out of the micelles and interaction of the nonmicellar CN to form a network that further strengthened the random loose jamming gel structure or to a gradual increase in voluminosity of the casein micelles during storage at 4°C.
Topics: Animals; Caseins; Gels; Micelles; Milk; Viscosity
PubMed: 34531054
DOI: 10.3168/jds.2021-20658 -
Biochimica Et Biophysica Acta.... Nov 2022The human ocular lens consists primarily of elongated, static fibers characterized by high stability and low turnover, which differ dramatically in their composition and...
The human ocular lens consists primarily of elongated, static fibers characterized by high stability and low turnover, which differ dramatically in their composition and properties from other biological membranes. Cholesterol (Chol) and sphingolipids (SL) are present at high concentrations, including saturated SLs, such as dihyrosphingomyelin (DHSM). Past molecular dynamics simulations demonstrated that the presence of DHSM and high Chol concentration contributes to higher order in lipid membranes. This current study simulated more complex models of human lens membranes. Models were developed representing physiological compositions in cataractous lenses aged 74 ± 6 years and in healthy lenses aged 22 ± 4, 41 ± 6, and 69 ± 3 years. With older age, Chol and ceramide concentrations increase and glycerophospholipid concentration decreases. With cataract, ceramide concentration increases and Chol and glycerophospholipid concentrations decrease. Surface area per lipid, deuterium order parameters (S), sterol tilt angle, electron density profiles, bilayer thickness, chain interdigitation, two-dimensional radial distribution functions (2D-RDF), lipid clustering, and hydrogen bonding were calculated for all simulations. All systems exhibited low surface area per lipid and high bilayer thickness, indicative of strong vertical packing. S parameters suggest similarly, with saturated tails in the hydrophobic core of the membrane having elevated order. Vertical packing and acyl tail order increased with both age and cataract condition. Lateral diffusion decreased with age and cataracts, with the older and cataractous models demonstrating increased long-range structure by the 2D-RDF analysis. In future work examining the membrane proteins of the lens, these models can serve as a physiologically accurate representation of the lens lipidome.
Topics: Cataract; Ceramides; Cholesterol; Glycerophospholipids; Humans; Molecular Dynamics Simulation
PubMed: 35944665
DOI: 10.1016/j.bbamem.2022.184025 -
Medicine and Science in Sports and... Jul 2022This study aimed to examine the effects of fatiguing power loading on neuromuscular properties, force production, and metabolic capacities during four phases of the...
PURPOSE
This study aimed to examine the effects of fatiguing power loading on neuromuscular properties, force production, and metabolic capacities during four phases of the menstrual cycle (MC): menstruation (M), midfollicular (mid FOL), ovulation (OV), and midluteal (mid LUT).
METHODS
Sixteen eumenorrheic women performed sessions of maximal explosive leg press (2 × 10 at 60% one-repetition maximum load with 2-min recovery between sets). Serum hormones and neuromuscular responses were measured.
RESULTS
The loading protocol significantly decreased power (between -14.2% and -12.5%; P < 0.001) and maximal force production (between maximum voluntary force (MVC); -15.0% and -7.8%; P < 0.001-0.05), while decreasing activation level (between AL; -6.9% and -2.2%; P < 0.001-0.05) in all MC phases. The decreases in AL were greater during mid LUT (P < 0.01) compared with OV. Changes in MVC and AL were associated (r2 = 0.53; P < 0.01) at all MC phases. The decrease in EMG during MVC did not differ between the MC phases; however, mean power frequency was higher during M (+7.7%; P < 0.05) and mid LUT (+3.1%; P < 0.05) compared with OV (-7.5%). Resting twitch force decreased during mid FOL (-6.9%; P < 0.05) and mid LUT (-16.2%; P < 0.001), and these values were significantly decreased (P < 0.05) compared with OV. In addition, resting twitch force at mid LUT was lower (P < 0.01) compared with M. Blood lactate levels increased more (P < 0.05) during M compared with mid LUT. Some serum hormone concentrations were associated with fatigue-induced changes in neuromuscular properties and force production, but these correlations behaved differently between the MC phases.
CONCLUSIONS
OV may offer a more favorable hormonal milieu for acute neural responses, whereas mid FOL and mid LUT seem to be superior for acute muscular responses.
Topics: Electromyography; Female; Hormones; Humans; Menstrual Cycle; Menstruation; Muscle Fatigue; Muscle, Skeletal; Rest; Weight Lifting
PubMed: 35320150
DOI: 10.1249/MSS.0000000000002904 -
Genes Oct 2022Oxidative stress has been implicated in the initiation of acute pancreatitis (AP). HDL is considered to be a preventing factor against cell membrane oxidation, thanks to...
Importance of Polymorphisms in the Gene of Paraoxonase-1 (SNP rs662) and Apolipoprotein A-I (SNP rs670 and rs5069) in Non-Smoking and Smoking Healthy Subjects and Patients with Acute Pancreatitis.
Oxidative stress has been implicated in the initiation of acute pancreatitis (AP). HDL is considered to be a preventing factor against cell membrane oxidation, thanks to the presence on its surface of apolipoprotein A-I (apoA-I) and paraoxonase-1 (PON1), which activity can be modified by genetic and environmental factors. The impact of SNP rs662 in the gene and SNP rs670 and rs5069 in the gene on PON1 activities and its concentration in the population of AP patients and healthy volunteers was investigated. In the group of patients with AP, a decreased HDL concentration and PON1 activities were observed. A decrease in the aryloesterase and lactonase activities of PON1 in AP patients with the TT genotype for SNP rs662 (especially in smokers) was found. In the group of patients with the AA genotype (rs670), the highest concentrations of HDL and apoA-I were observed, which were gradually decreasing in the course of AP. Changes in the concentration of apoA-I were associated with the changes in the concentration and activities of PON1 in the AP patients with the AA genotype for SNP rs670. A decreasing apoA-I concentration contributing to lowering PON1 concentration and its activities during the hospitalization of AP patients with the CC genotype for SNP rs5069 were shown. Therefore, more susceptibility of persons with the CC genotype for SNP rs5069 to pro/antioxidative imbalance was shown. In this process, an important role was played by the HDL level and its interaction with PON1 and apoA-I.
Topics: Humans; Aryldialkylphosphatase; Apolipoprotein A-I; Healthy Volunteers; Acute Disease; Pancreatitis
PubMed: 36360205
DOI: 10.3390/genes13111968 -
Frontiers in Veterinary Science 2020To evaluate the hematologic components of platelet-rich plasma (PRP) generated using feline blood with two commercially available centrifuge-based systems. Twenty...
To evaluate the hematologic components of platelet-rich plasma (PRP) generated using feline blood with two commercially available centrifuge-based systems. Twenty healthy adult cats were enrolled in this prospective study from November 2018 to January 2019. Feline blood samples were obtained for analysis of whole blood (WB) cellular components and preparation of PRP product. PRP was prepared using two commercial systems and complete blood count (CBC) testing was performed on both WB and PRP samples. The cellular composition of the PRP product was compared to the WB sample for each patient. Both systems showed significant decrease of median RBC concentration in PRP products compared to WB samples ( = 0.002 for both systems). System 1 significantly decreased median WBC concentration ( = 0.002). System 2 decreased WBC concentration, though statistical significance was not reached ( = 0.63). Median platelet concentration was decreased by 3% using System 1, and increased by 187% using System 2. Platelet aggregation presented a challenge with 8/20 (40%) of samples demonstrating platelet aggregation. Commercial systems available for generation of PRP may be useful for creating a feline sourced product and in this study showed promise in decreasing RBC and WBC concentration. Neither system tested achieved 2-5 times platelet concentration from baseline. Platelet aggregation presented a significant obstacle to reliable generation of PRP products using feline blood. This treatment modality may be particularly beneficial for feline patients with osteoarthritis and soft tissue injuries, though first characterizing the PRP product made using feline blood is critical to validate its use in further clinical studies.
PubMed: 32596269
DOI: 10.3389/fvets.2020.00322 -
Membranes Nov 2022Cell membrane lipid composition, especially cholesterol, affects many functions of embedded enzymes, transporters and receptors in red blood cells (RBC). High membrane... (Review)
Review
Cell membrane lipid composition, especially cholesterol, affects many functions of embedded enzymes, transporters and receptors in red blood cells (RBC). High membrane cholesterol content affects the RBCs' main vital function, O and CO transport and delivery, with consequences on peripheral tissue physiology and pathology. A high degree of deformability of RBCs is required to accommodate the size of micro-vessels with diameters significantly lower than RBCs. The potential therapeutic role of high-density lipoproteins (HDL) in the removal of cholesterol and its activity regarding maintenance of an optimal concentration of RBC membrane cholesterol have not been well investigated. On the contrary, the focus for HDL research has mainly been on the clearance of cholesterol accumulated in atherosclerotic macrophages and plaques. Since all interventions aiming at decreasing cardiovascular diseases by increasing the plasma level of HDL cholesterol have failed so far in large outcome studies, we reviewed the potential role of HDL to remove excess membrane cholesterol from RBC, especially in sickle cell disease (SCD). Indeed, abundant literature supports a consistent decrease in cholesterol transported by all plasma lipoproteins in SCD, in addition to HDL, low- (LDL) and very low-density lipoproteins (VLDL). Unexpectedly, these decreases in plasma were associated with an increase in RBC membrane cholesterol. The concentration and activity of the main enzyme involved in the removal of cholesterol and generation of large HDL particles-lecithin cholesterol ester transferase (LCAT)-are also significantly decreased in SCD. These observations might partially explain the decrease in RBC deformability, diminished gas exchange and tendency of RBCs to aggregate in SCD. We showed that incubation of RBC from SCD patients with human HDL or the HDL-mimetic peptide Fx5A improves the impaired RBC deformability and decreases intracellular reactive oxygen species levels. We propose that the main physiological role of HDL is to regulate the cholesterol/phospholipid ratio (C/PL), which is fundamental to the transport of oxygen and its delivery to peripheral tissues.
PubMed: 36422126
DOI: 10.3390/membranes12111134 -
Acta Haematologica 2021Congenital fibrinogen deficiency is an inherited disorder due to genetic mutations with diverse presentations arising from reduced fibrinogen levels... (Review)
Review
Congenital fibrinogen deficiency is an inherited disorder due to genetic mutations with diverse presentations arising from reduced fibrinogen levels (hypofibrinogenemia), absence of fibrinogen in circulation (afibrinogenemia), abnormal functioning (dysfibrinogenemia) or both reduced levels and abnormal functioning (hypodysfibrinogenemia) of fibrinogen. The decreased fibrinogen concentration in congenital fibrinogen deficiency necessitates fibrinogen replacement therapy with fresh frozen plasma, cryoprecipitate, or human fibrinogen concentrate. However, the use of fresh frozen plasma and cryoprecipitate is limited owing to their longer transfusion time, requirement of high doses, volume overload, risk of viral transmission, and other safety concerns. The availability of human fibrinogen concentrate has made it the preferred replacement alternative due to its reduced risk of viral transmission, smaller infusion volume, and accurate dosing. The hemostatic efficacy and safety of human fibrinogen concentrate in congenital fibrinogen deficiency is well established in the literature. We review the prevalence of congenital fibrinogen deficiency in India and the current role of human fibrinogen concentrate in its management.
Topics: Afibrinogenemia; Blood Transfusion; Fibrinogen; Guidelines as Topic; Humans; India; Plasma
PubMed: 34091452
DOI: 10.1159/000516339 -
Journal of Dairy Science May 2022The objective of this study was to investigate whether the CH mitigation potential of 3-nitrooxypropanol (3-NOP) in dairy cattle was affected by basal diet (BD)...
The objective of this study was to investigate whether the CH mitigation potential of 3-nitrooxypropanol (3-NOP) in dairy cattle was affected by basal diet (BD) composition. The experiment involved 64 Holstein-Friesian dairy cows (146 ± 45 d in milk at the start of trial; mean ± SD) in 2 overlapping crossover trials, each consisting of 2 measurement periods. Cows were blocked according to parity, d in milk, and milk yield, and randomly allocated to 1 of 3 diets: a grass silage-based diet (GS) consisting of 30% concentrates and 70% grass silage (DM basis), a grass silage- and corn silage-mixed diet (GSCS) consisting of 30% concentrates, 42% grass silage, and 28% corn silage (DM basis), or a corn silage-based diet (CS) consisting of 30% concentrates, 14% grass silage, and 56% corn silage (DM basis). Two types of concentrates were formulated, viz. a concentrate for the GS diet and a concentrate for the CS diet, to meet the energy and protein requirements for maintenance and milk production. The concentrate for the GSCS diet consisted of a 50:50 mixture of both concentrates. Subsequently, the cows within each type of BD received 2 treatments in a crossover design: either 60 mg of 3-NOP/kg of DM (NOP60) and a placebo with 0 mg of 3-NOP/kg of DM (NOP0) in one crossover or 80 mg of 3-NOP/kg of DM (NOP80) and NOP0 in the other crossover. Diets were provided as total mixed ration in feed bins, which automatically recorded feed intake. Additional concentrate was fed in the GreenFeed system that was used to measure emissions of CH and H. The CS diets resulted in a reduced CH yield (g/kg DMI) and CH intensity (g/kg milk). Feeding 3-NOP resulted in a decreased DMI. Milk production and composition did not differ between NOP60 and NOP0, whereas milk yield and the yield of major components decreased for NOP80 compared with NOP0. Feed efficiency was not affected by feeding 3-NOP. Interactions between BD and supplementation of 3-NOP were observed for the production (g/d) and yield (g/kg DMI) of both CH and H, indicating that the mitigating effect of 3-NOP depended on the composition of the BD. Emissions of CH decreased upon 3-NOP supplementation for all BD, but the decrease in CH emissions was smaller for GS (-26.2% for NOP60 and -28.4% for NOP80 in CH yield) compared with both GSCS (-35.1% for NOP60 and -37.9% for NOP80 for CH yield) and CS (-34.8% for NOP60 and -41.6% for NOP80 for CH yield), with no difference between the latter 2 BD. Emissions of H increased upon 3-NOP supplementation for all BD, but the H yield (g/kg DMI) increased 3.16 and 3.30-fold, respectively, when NOP60 and NOP80 were supplemented to GS, and 4.70 and 4.96 fold, respectively, when NOP60 and NOP80 were supplemented to CS. In conclusion, 3-NOP can effectively decrease CH emissions in dairy cows across diets, but the level of CH mitigation is greater when supplemented in a corn silage-based diet compared with a grass silage-based diet.
Topics: Animals; Cattle; Diet; Female; Lactation; Methane; Poaceae; Pregnancy; Propanols; Silage; Zea mays
PubMed: 35221072
DOI: 10.3168/jds.2021-20782 -
Food Research International (Ottawa,... Nov 2023New processes are needed to produce concentrated milk feedstocks with tailored calcium content, due to the direct link between calcium concentration and final product...
New processes are needed to produce concentrated milk feedstocks with tailored calcium content, due to the direct link between calcium concentration and final product texture and functionality. Skim milk treatment with cation exchange resin 1% (w/v) or 2% (w/v) prior to ultrafiltration to a volumetric concentration factor (VCF) of 2.5 or 5 successfully decreased the calcium concentration by 20-30% and produced concentrates with solids content at ∼22-24 g 100 g at a VCF of 5. Calcium reduction partially solubilized the casein micelles, increasing the concentration of soluble protein and individual caseins, leading to decreased turbidity but increased protein hydration and hydrophobicity. Decalcification (2% (w/v) resin treatment) reduced thermal stability, significantly decreasing the denaturation temperature of α-lactalbumin and β-lactoglobulin in the milk by ∼3 °C and ∼1 °C respectively. Filtration was also altered, reducing permeation flux and the gel concentration and increased filtration time. When combined, calcium reduction and filtration altered functional properties including soluble calcium, soluble protein and sedimentable solids, with increased milk protein hydration also contributing to increased viscosity. This study provides a route to produce calcium-reduced milk concentrates with potential for use in retentate-based dairy products with tailored functionality.
Topics: Animals; Ultrafiltration; Calcium; Ion Exchange; Food Handling; Milk; Caseins; Calcium, Dietary
PubMed: 37803619
DOI: 10.1016/j.foodres.2023.113305 -
Kidney & Blood Pressure Research 2023Hemodialysis is one of the most resources consuming medical intervention. Due to its concept, the proper amount of dialysis fluid passed through dialyzer is crucial to... (Review)
Review
BACKGROUND
Hemodialysis is one of the most resources consuming medical intervention. Due to its concept, the proper amount of dialysis fluid passed through dialyzer is crucial to obtain the expected outcomes. The most frequent source of dialysis fluid is production from liquid concentrate (delivered in containers or plastic bags) in dialysis machine. Alternatively, concentrates for dialysis may be produced in dialysis center by dilution in mixing devices dry or semidry premixed compounds connected with system of central dialysis fluid delivery system. Dialysate consumption depends on various factors like type of hemodialysis machine, session duration, prescribed flow, etc. Summary: Modern hemodialysis machines are equipped with the modules which automatically reduce flow rate of dialysis fluid to the patient blood flow and minimize dialysate consumption during preparation and after reinfusion. Smart using of available options offered by manufacturers allows to save additional portion of acid concentrate and water. The weight of concentrates to be delivered to the dialysis center is the major factor influencing the cost (financial and environmental) of transportation from the manufacturer to the final consumer. The crisis on the energy carriers market and extremely high fuel prices made the transportation cost one of the significant costs of the treatment, which must be bear by supplier and finally influence on the price of goods.
KEY MESSAGES
The careful choice of the concentrate delivery system can improve cost-effectiveness of dialysis. Such solutions implemented in dialysis unit helps make significant savings and decrease the impact on natural environment by carbon footprint reduction.
Topics: Humans; Renal Dialysis; Dialysis Solutions
PubMed: 37166319
DOI: 10.1159/000530439