Variations in milk protein fractions affect the efficiency of the cheese-making process

The aim of this study was to assess the influence of the amounts of the α_S1-, α_S2-, β-, and κ-casein (CN) and the α-lactalbumin and β-lactoglobulin protein fractions on the efficiency of the cheese-making process independently of their genetic polymorphisms. The study was carried out on milk samples from 1,271 Brown Swiss cows from 85 herds classified into 4 categories according to management, feeding, and housing characteristics (traditional and modern systems). To assess the efficiency of the cheese-making process, we processed the milk samples according to a laboratory cheese-making procedure (1,500 mL/sample) and obtained the following measures: (1) 3 percentage cheese yields (%CY_curd, %CY_solids, %CY_water), (2) 2 daily cheese yields obtained by multiplying %CY (curd and total solids) by daily milk yields (dCY_curd, dCY_solids), (3) 4 measures of nutrient recovery in the curd (REC_fat, REC_protein, REC_solids, REC_energy), and (4) 2 measures of cheese-making efficiency in terms of the ratio between the observed and theoretical %CY (Ef-%CY_curd, Ef-%CY_solids). All the aforementioned traits were analyzed by fitting 2 linear mixed models with protein fractions as fixed effects expressed as percentage in the milk (model M-%milk) and as percentage of the total casein content (model M-%cas) together with the effects of total casein content (only in model M-%cas), daily milk yield (only in model M-%milk; not for dCY traits), dairy system, herd (random effect), days in milk, parity, and vat. The efficiency of overall cheese yield (Ef-%CY_curd) was mostly positively associated with β-CN content in the milk, whereas Ef-%CY_solids was greater with higher amounts of κ-CN and α_S1-CN (M-%milk) due to the strong influence of both fractions on the recovery rate of milk components in the curd (fat and total solids, protein with α_S1-CN only) when expressed as percentage of milk and of total casein; only β-CN was more important for REC_protein. In contrast, we found β-lactoglobulin to be highly negatively related to all the traits related to the cheese-making process and to the daily cheese yield per cow, whereas α-lactalbumin was positively associated with the latter traits. Additional research on this topic is needed, with particular focus on the genetic and genomic aspects of the role of protein fractions in the cheese-making process and on the associations between genetic polymorphisms in milk protein and milk nutrient recovery in the curd.     

Partitioning and bioaccumulation of PBDEs and PCBs in Lake Michigan

Water from Lake Michigan and fish from all five Great Lakes have been sampled and analyzed for a suite of six polybrominated diphenyl ether (PBDE) congeners and 110 polychlorinated biphenyl congeners (PCBs). The Lake Michigan dissolved phase PBDE congener concentrations (0.2 to 10 pg/L) are similar to dissolved phase PCB congener concentrations (nondetected to 13 pg/L). Partitioning of PBDEs between the particulate and dissolved phases exhibits behavior similar to that of PCBs. Organic-carbon-normalized water-particle partition coefficients (log K(OC)s) ranged from 6.2 to 6.5. Lake trout are depleted in BDE-99 relative to dissolved phase concentrations, and in contrast to what is expected from the PCB congener patterns. This reflects suspected debromination of BDE-99 in the food web of Lake Michigan. A regression of the log of the bioaccumulation factor (BAF) and the log of the octanol-water partition coefficent (K(OW)) indicated a positive relationship for both PCB congeners and PBDE congeners. BDE-99 does not appear to followthe same trend, a further indication that it is subject to biotransformation. Using the PBDE BAFs for Lake Michigan and the PBDE fish concentrations from the other Great Lakes it is expected that the dissolved phase concentrations of congeners in the other lakes would range from 0.04 to approximately 3 pg/L.     

Effects of traumatic brain injury on working memory-related brain activation in adolescents.

Eight adolescents (ages 13-18 years) who sustained traumatic brain injury (TBI) and eight gender- and age-matched typically developing (TD) adolescents underwent event-related functional MRI (fMRI) while performing a Sternberg letter recognition task. Encoding, maintenance, and retrieval were examined with memory loads of one or four items during imaging. Both groups performed above a 70% accuracy criterion and did not differ in performance. TD adolescents showed greater increase in frontal and parietal activation during high-load relative to low-load maintenance than the TBI group. The TBI patients showed greater increase in activation during high-load relative to low-load encoding and retrieval than the TD group. Results from this preliminary study suggest that the capability to differentially allocate neural resources according to memory load is disrupted by TBI for the maintenance subcomponent of working memory. The overrecruitment of frontal and extrafrontal regions during encoding and retrieval following TBI may represent a compensatory process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intraportal lipopolysaccharide suppresses pulmonary antibacterial defense mechanisms

Translocation of enteric bacteria or their components (or both) has been postulated to play a role in precipitating sepsis or the systemic inflammatory response syndrome. To simulate the effects of translocation on pulmonary host defenses, lipopolysaccharide was injected into the portal vein of normal rats that were subsequently challenged by aerosol inoculation with Pseudomonas aeruginosa. Injection of LPS into the portal vein resulted in increased serum tumor necrosis factor (TNF)-alpha levels and reduction in lung clearance of P. aeruginosa after aerosol challenge. There were corresponding reductions in alveolar neutrophil recruitment, diminished alveolar macrophage phagocytosis and superoxide anion (O2-) production, and diminished lung TNF recovered by bronchoalveolar lavage. Furthermore, prior intravenous injection of recombinant TNF-alpha reproduced the defective bacterial clearance, the altered recruitment of airspace neutrophils, and the defective alveolar macrophage phagocytosis. Thus, systemic TNF-alpha is important in altering pulmonary defenses, and this work supports the concept that bacterial translocation may adversely affect host defenses in distant organs.     

Early transition to oral antibiotic therapy for community-acquired pneumonia: duration of therapy, clinical outcomes, and cost analysis

Our objective was to compare therapeutic outcome and analyse cost-benefit of a 'conventional' (7-day course of i.v. antibiotic therapy) vs. an abbreviated (2-day i.v. antibiotic course followed by 'switch' to oral antibiotics) therapy for in-patients with community-acquired pneumonia (CAP). We used a multicenter prospective, randomized, parallel group with a 28 day follow-up, at the University-based teaching hospitals: The Medical Center of Louisiana in New Orleans, LA and hospitals listed in the acknowledgement. Ninety-five patients were randomized to receive either a 'conventional' course of intravenous antibiotic therapy with cefamandole 1 g i.v. every 6 h for 7 days (n = 37), or an abbreviated course of intravenous therapy with cefamandole (1 g i.v. every 6 h for 2 days) followed by oral therapy with cefaclor (500 mg every 8 h for 5 days). No difference was found in the clinical courses, cure rates, survival or the resolution of the chest radiograph abnormalities among the two groups. The mean duration of therapy (6.88 days for the conventional group compared to 7-30 days for the early oral therapy group) and the frequencies of overall symptomatic improvement (97% vs. 95%, respectively) were similar in both groups. Patients who received early oral therapy had shorter hospital stays (7.3 vs. 9.71 days, P = 0.01), and a lower total cost of care ($2953 vs. $5002, P < 0.05). It was concluded that early transition to an oral antibiotic after an abbreviated course of intravenous therapy in CAP is substantially less expensive and has comparable efficacy to conventional intravenous therapy. Altering physicians' customary management of hospitalized patients with CAP can reduce costs with no appreciable additional risk of adverse patient outcome.     

Will the Revolution be Tweeted or Facebooked? Using Digital Communication Tools in Immigrant Activism

Considering the debate over U.S. immigration reform and the way digital communication technologies increasingly are being used to spark protests, this qualitative study examines focus group discourse of immigration activists to explore how digital media are transforming the definitions of “activism” and “activist.” Analysis suggests technologies are perhaps pacifying would‐be activists, convincing them they are contributing more than they actually are. Thus, “slacktivism,” or “clicktivism” that takes just a mouse click is potentially diluting “real” activism.     

Correlates of social problem solving during the first year after traumatic brain injury in children.

Effects of pediatric traumatic brain injury (TBI) on social problem-solving were examined in a longitudinal study of 103 children with moderate-to-severe TBI (n = 52) or orthopedic injury (OI; n = 51) using the Interpersonal Negotiation Strategies task (INS). Children solved age-appropriate hypothetical social conflicts, with responses for four problem-solving steps scored by developmental level. The OI group performed better than the TBI group, but rate of change in performance over time did not differ between groups, suggesting improvement in children with TBI was not due to recovery from injury. Strong relations between INS performance and memory and language skills emerged, but emotional processing was only weakly related to INS performance. Frontal focal lesions influenced INS performance in younger (but not older) children with TBI. Diffusion tensor imaging (DTI), revealed strong relationships between the INS and increased apparent diffusion coefficient (ADC) measures indexing connectivity in the dorsolateral and cingulate regions in both TBI and OI groups, and in the temporal and parietal regions in the TBI group. These findings inform studies of social problem-solving skills during the first year post TBI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)