Influence of Saccharomyces cerevisiae fermentation products, SmartCare in milk replacer and Original XPC in calf starter, on the performance and health of preweaned Holstein calves challenged with Salmonella enterica serotype Typhimurium.

This study was designed to investigate the effects of supplementing SmartCare (SC; Diamond V, Cedar Rapids, IA) in milk replacer and Original XPC (XPC; Diamond V) in calf starter on performance and health of preweaned calves following an oral challenge with Salmonella enterica. The study was performed in two 35-d periods with 30 Holstein bull calves (2 ± 1 d of age) per period. In each period, calves were blocked by location in the barn and randomly assigned to treatments that included control, base milk replacer and calf starter with no added Saccharomyces cerevisiae fermentation products; SC, milk replacer with 1 g of SC/calf per day and base calf starter; and SC+XPC, milk replacer with 1 g of SC/calf per day and calf starter with 0.5% XPC on a dry matter basis. Calves were fed 350 g of milk replacer solids at 14% dry matter twice daily at 0700 and 1700 h. Calf starter and water were offered ad libitum and intakes were recorded daily. Calves were challenged with 108 cfu of sulfamethazine-resistant Salmonella enterica serotype Typhimurium orally on d 14 of the study. Fecal Salmonella shedding was determined on d 14 to 21 (daily), 24, 28, and 35 using selective media. Blood samples were collected on d 0, 7, 14, 16, 18, 21, 24, 28, and 35 and analyzed for hematology; plasma were analyzed for haptoglobin concentrations. All data were reported as CON, SC, and SC+XPC, respectively. Calf starter intake was increased from d 22 to 35 among SC+XPC calves and from d 29 to 35 among SC calves. The SC+XPC calves had a lower neutrophil-to-lymphocyte ratio (0.81, 0.83, and 0.69 ± 0.051) throughout the study. The SC+XPC calves also had lower hematocrits (35.1, 35.3, and 33.4 ± 0.54%) and hemoglobin concentrations (10.8, 10.6, and 10.1 ± 0.16 mg/dL) throughout the study. We found a tendency for calves fed SC and SC+XPC to have more solid fecal scores during the week after the challenge. We observed no treatment or treatment × time differences on plasma haptoglobin concentrations (63, 48, and 60 ± 0.5 µg/mL). No treatment differences were observed in the fecal shedding of the Salmonella; however, we noted a tendency for a treatment difference in the percentage of calves positive for Salmonella present in the ileal tissue at d 21 after the challenge (25, 50, and 60%). Supplementing preweaned Holstein calves with both SC in milk replacer and XPC in calf starter improved starter intake and improved fecal consistency immediately after a mild Salmonella enterica challenge, but more data are needed to further understand how these yeast fermentation products influence the immune responses to Salmonella enterica.

Why wait? Three mechanisms selecting for environment-dependent developmental delays.

Many species delay development unless particular environments or rare disturbance events occur. How can such a strategy be favoured over continued development? Typically, it is assumed that continued development (e.g. germination) is not advantageous in environments that have low juvenile/seedling survival (mechanism 1), either due to abiotic or competitive effects. However, it has not previously been shown how low early survival must be in order to favour environment-specific developmental delays for long-lived species. Using seed dormancy as an example of developmental delays, we identify a threshold level of seedling survival in 'bad' environments below which selection can favour germination that is limited to 'good' environments. This can be used to evaluate whether observed differences in seedling survival are sufficient to favour conditional germination. We also present mathematical models that demonstrate two other, often overlooked, mechanisms that can favour conditional germination in the absence of differences in seedling survival. Specifically, physiological trade-offs can make it difficult to have germination rates that are equally high in all environments (mechanism 2). We show that such trade-offs can either favour conditional germination or intermediate (mixed) strategies, depending on the trade-off shape. Finally, germination in every year increases the likelihood that some individuals are killed in population-scale disturbances before reproducing; it can thus be favourable to only germinate immediately after a disturbance (mechanism 3). We demonstrate how demographic data can be used to evaluate these selection pressures. By presenting these three mechanisms and the conditions that favour conditional germination in each case, we provide three hypotheses that can be tested as explanations for the evolution of environment-dependent developmental delays.

A negative selection methodology using a microfluidic platform for the isolation and enumeration of circulating tumor cells.

Circulating tumor cells (CTCs) exist in the peripheral blood stream of metastatic cancer patients at rates of approximately 1 CTC per billion background cells. In order to capture and analyze this rare cell population, various techniques exist that range from antibody-based surface marker positive selection to methods that use physical properties of CTCs to negatively exclude background cells from a CTC population. However, methods to capture cells for functional downstream analyses are limited due to inaccessibility of the captured sample or labeling techniques that may be prohibitive to cell function. Here, we present a negative selection method that leverages a Microfluidic Cell Concentrator (MCC) to allow collection and analysis of this rare cell population without needing cell adhesion or other labeling techniques to keep the cells within the chamber. Because the MCC is designed to allow collection and analysis of non-adherent cell populations, multiple staining steps can be applied in parallel to a given CTC population without losing any of the population. The ability of the MCC for patient sample processing of CTCs for enumeration was demonstrated with five patient samples, revealing an average of 0.31 CTCs/mL. The technique was compared to a previously published method - the ELISPOT - that showed similar CTC levels among the five patient samples tested. Because the MCC method does not use positive selection, the method can be applied across a variety of tumor types with no changes to the process.

[Diagnosis and treatment of infectious pharyngeal inflammation].

Symptoms of viral and/or streptococcal infectious pharyngitis are of interest in the context of different therapeutic strategies. This study involved 3 family medicine clinics, one emergency service department, and 694 patients. Streptococcal pharyngitis occurred in 24% of the adult patients and in 29% of all the patients. The remaining ones had acute viral pharyngitis or a mixed viral/bacterial infection. Medicamentous therapy given to 98% of the patients included local antibiotics (42%), systemic antibacterial monotherapy (12%), and combined antibiotic therapy (44%). Lysozime-containing preparations (larypront, dequalar, etc.) recommended for pathogenetic therapy had the active ingredient in the form of a dequalinium complex to deliver lysozime to pharyngeal mucosa. The frequency of streptococcal infection in patients with secondary sore throat receiving the combined treatment was twice lower (12%) than in the general group. The strategy of therapy was the same as in primary sore throat.

Predictors of retained hemothorax after trauma and impact on patient outcomes.

PURPOSE: Hemo/pneumothoraces are a common result of thoracic injury. Some of these injuries will be complicated by retained hemothorax (RH), which has previously been shown to be associated with longer hospitalizations. It has been proposed that early versus delayed intervention with video-assisted thoracoscopic surgery can reduce the duration of mechanical ventilation, hospital and ICU LOS, and costs in patients with RH. However, little is known regarding the effect of RH on these outcomes relative to patients with uncomplicated hemo/pneumothoraces. The aim of our study was to characterize factors present on admission that may be associated with RH and assess the impact of RH on outcomes. METHODS: A retrospective chart review was conducted and included all patients who underwent tube thoracostomy (TT) for traumatic hemo/pneumothorax admitted to a single urban adult and pediatric level I trauma center from January 2008 to September 2013. RESULTS: The study cohort included 398 patients, 17.6 % developed RH. RH was associated with significantly longer total duration of TT drainage (p < 0.001), hospital LOS (p < 0.001), and total hospital charges (p < 0.001). These associations remained significant in a subgroup analysis excluding patients with traumatic brain injury. Patients with bilateral injuries (OR 4.25, p < 0.001) and patients intubated on the day of admission (OR 2.30, p = 0.002) were significantly more likely to develop RH. There was also a small, but highly significant, association between increasing ISS and the development of RH (OR 1.07, p < 0.001). CONCLUSIONS: Our study suggests patients requiring ventilator support on admission and those with bilateral injuries are at increased risk of developing RH. Early identification of patients at risk for RH may allow for earlier intervention and potential benefits to the patient.

Effects of Saccharomyces cerevisiae fermentation products on the lactational performance of mid-lactation dairy cows.

This study was to evaluate 1 current and 2 newly developed Saccharomyces cerevisiae fermentation products (SCFP, Diamond V Original XPC and 2 test products) on the production efficiency of mid-lactation dairy cows. Eighty mid-lactation (164.5 ± 67.5 d in milk: DIM) Holstein cows (56 multiparous and 24 primiparous) were blocked by parity, DIM, and milk production, and randomly assigned to 1 of 4 treatments. Treatments consisted of: 1) Control (CON): corn silage and haylage based ration; 2) XPC: CON ration with Original XPC added at 14 g/d; 3) Product 1 (P1): CON ration with Product 1 added at 5 g/d; and 4) Product 2 (P2): CON ration with Product 2 added at 19 g/d. Treatments were blended with dried distillers grains and then mixed into a total mixed ration at 454 g/d. The first 14 d of the study (d-14 to 0) was for training cows to use the Calan door feeding system and cows were fed the CON ration during this period followed by an 8 wk continuous experimental period. Dry matter intakes were similar (P > 0.10) when cows were fed all treatments (25.7, 26.1, 25.1, and 26.2 kg/d for CON, XPC, P1, and P2, respectively). Milk production (33.3, 34.4, 35.5, and 36.8 kg/d) was improved (P < 0.05) for cows fed P2 compared to cows fed CON, with cows fed other treatments being intermediate and similar (P > 0.10). Feed efficiency (milk yield/dry matter intake) was improved (P < 0.05) for cows fed P1 and P2, compared to cows fed CON and XPC (1.30, 1.34, 1.49 and 1.41 kg/kg). Milk fat content was reduced (P < 0.05) for cows fed P2 (4.17, 3.93, 4.08, and 3.85%) compared to cows fed CON, with cows fed other treatments being intermediate (P > 0.10). Milk protein and lactose percentages were similar (P > 0.10) among treatments. Cows fed P2 had reduced (P < 0.05) molar proportion of ruminal acetate (63.8, 64.0, 63.1, and 62.3%) and greater (P < 0.05) propionate (18.9, 19.3, 19.7, and 20.6%) than cows fed other treatments. Supplementing a dairy ration with SCFP, such as P2, can improve milk production and feed efficiency of mid-lactation cows.

Inhibition of the virulence, antibiotic resistance, and fecal shedding of multiple antibiotic-resistant Salmonella Typhimurium in broilers fed Original XPC™.

Salmonella carriage is an insidious problem for the poultry industry. While most Salmonella serotypes are avirulent in poultry, these bacteria can contaminate chicken meat during processing, leading to one of the most important food safety hazards. In this study, we examined the anti-Salmonella effects of Diamond V Original XPC™ (XPC) included in the finisher diet fed to commercial broilers. On 3 occasions between day one (D1) and D20, broilers were experimentally infected with multiple antibiotic-resistant Salmonella Typhimurium. After confirming that the chicks were shedding Salmonella in the feces on D21, broiler chicks were fed a diet containing XPC (n = 57 birds; 1.25 kg/MT) or an XPC-free control diet (CON) (n = 57 birds) to D49. Fecal samples were obtained weekly and subjected to selective culture for enumerating and determining the antibiotic resistance of the Salmonella Salmonella isolates were then subjected to an in vitro virulence assay, which predicts the ability of Salmonella to cause illness in a mammalian host. Broilers were euthanized on D49 and a segment of the large intestine was removed and subjected to the same assays used for the fecal samples. When compared to the birds fed the CON diet, Salmonella fecal shedding, virulence (invasion and invasion gene expression), and antibiotic resistance were significantly decreased in birds fed XPC (5-fold, 7.5-fold, 6-fold, and 5.3-fold decreases, respectively). Birds fed XPC exhibited heavier body weight (BW) and greater BW gains than those fed the CON diet. The decrease in virulence was associated with a decreased expression of a genetic regulator of Salmonella invasion into cells (hilA), while the decrease in antibiotic resistance was due to a loss of an integron (SGI1) from the input strain. This study revealed that Original XPC™ inhibits the shedding, downstream virulence, and antibiotic resistance of Salmonella residing in broilers.

Genetic engineering of hybridoma glutamine metabolism.

The murine hybridoma PQXB1/2 cannot be adapted to grow in culture media containing < 0.5 mM glutamine. Transformants selected following electroporation of PQXB1/2 cells with vectors containing a Chinese hamster glutamine synthetase (GS) cDNA under the control of the SV40 early promoter also failed to grow in the absence of glutamine in the culture medium. PQXB1/2 cells have, however, been transformed to glutamine independence following electroporation with a vector containing this glutamine synthetase cDNA under the control of the human cytomegalovirus immediate early promoter. In these cells, sufficient active glutamine synthetase was expressed from one vector per cell to enable growth in glutamine-free media. The specific activity of glutamine synthetase in two transformed cell lines producing parental levels of antibody was increased by 128 and 152%, respectively (0.57 and 0.63 mumol min-1 per 10(6) cells in transformants compared with parental levels of 0.25 mumol min-1 per 10(6) cells). This reprogramming of glutamine synthetase expression and glutamine metabolism is important for developing strategies to deal with ammonia toxicity and the production of cell lines with improved metabolic processes.

Growth hormone responsive dermatosis in three dogs.

Growth hormone responsive dermatosis was diagnosed in three dogs. Each dog showed truncal hair loss, and two animals also had alopecia of the ventral neck, tail and thighs. The diagnosis in two cases was made by eliminating other causes of hormonal alopecia and demonstrating little increase in plasma growth hormone concentration after the intravenous administration of xylazine. All three dogs responded favourably to the subcutaneous administration of recombinant human somatotropin.

Direct quantification of norepinephrine spillover and hormone output from the pancreas of the conscious dog.

To estimate pancreatic neural activity and to assess the potential role of the pancreatic nerves in the regulation of hormone secretion, the methodology necessary to quantify neurotransmitter spillover and hormone output in the conscious dog was developed. A femoral artery and the superior pancreaticoduodenal vein (SPDV) were chronically cannulated, and a flow probe was placed on the SPDV. Hormone output was calculated using the pancreatic arteriovenous concentration difference and the SPDV plasma flow. Basal glucose levels were 103 +/- 1 mg/dl; the pancreatic outputs of insulin, glucagon, and pancreatic polypeptide (PP, an index of parasympathetic neural activity) were 2,900 +/- 700 microU/min, 1,900 +/- 400 pg/min, and 9.3 +/- 4.6 ng/min, respectively. Pancreatic norepinephrine (NE) spillover was calculated similarly; however, pancreatic extraction of epinephrine was used as an index of NE extraction. Basal NE spillover was 3,600 +/- 700 pg/min, greatly exceeding that reported using anesthetized, laparotomized dogs. Intravenous glucose infusion increased plasma glucose to 146 +/- 13 mg/dl, increased insulin output approximately twofold, and suppressed glucagon output by approximately 50%. Hyperglycemia markedly reduced PP output. Hyperglycemia failed to influence pancreatic NE spillover. Insulin-induced hypoglycemia (36 +/- 2 mg/dl) completely suppressed insulin output and stimulated glucagon output (> 10-fold). Hypoglycemia increased NE spillover and PP output to 19,900 +/- 4,600 pg/min and 117 +/- 22 ng/min, respectively. We conclude that pancreatic neurotransmitter spillover in the basal state is much higher than previously appreciated and that neural signaling to the pancreas is responsive to physiological and pathophysiological changes in the metabolic state.

Enhancement of monoclonal antibody yield by hybridoma fed-batch culture, resulting in extended maintenance of viable cell population.

Hybridoma batch cultures were extended using feed formulations based on nutrient consumption measured during different batch culture phases when (a) growth but negligible antibody production was taking place; (b) maximum antibody production rate and declining viable cell growth rate were observed. Strategy (a) was the more successful (2.8-fold compared with 1.8-fold antibody titer increase) and maintained cell viability for longer. Analysis of the effects of omitting individual amino acids yielded results which were consistent with those from the feeding experiment.

A three-phase pattern in growth, monoclonal antibody production, and metabolite exchange in a hybridoma bioreactor culture.

The use of partial cubic spline data interpolation for the calculation of volumetric metabolite exchange rates suggested the existence of three distinct metabolic phases during bioreactor culture of a hybridoma cell line. During phase 1, a rapid amino acid uptake rate and ammonia release rate were observed. The growth rate was low and glutamine synthetase activity fell. In phase 2, maximum growth rate and minimum glutamine assimilation and ammonium production rates were observed. Attempts to corroborate the apparent ammonia assimilation in this phase using (15)NH(4)Cl resulted in low incorporation rates into alanine and glutamine. Maximum glutamine synthetase activity took place during this period. Maximum antibody production rate was observed during phase 3 during which peaks in glutamine assimilation, ammonia release, and glutamine synthetase activity were observed. The apparent existence of the three phases prompted us to carry out Northern blot analysis of glutamine synthetase RNA at appropriate times during the process. This revealed a pattern of appearance and dis-appearance of mRNA consistent with the three phases indicated by the fermentation parameters.