The Skewness of Alpha Beta T Cell Receptors in Peripheral Blood of the Patients with Type 1 Diabetes

AIM

To detect the skewness of TCR Vα and TCR Vβ of patients with type 1 diabetes (T1D).

METHODS

The heparinized venous blood was collected from ten patients with T1D. The peripheral blood lymphocytes (PBL) were isolated and used to extract mRNA. Reverse amplyfication was performed for cDNA synthesis. The skewness of TCR Vα and Vβ was detected with real-time florescence quantitative polymerase chain reaction (RQ-PCR) and analyzed by DNA melting-curve analysis technique, respectively.

RESULTS

Among the TCR Vα genes, the skewness frequency rate (SFR) of Vα22 was 30%; both of Vα5 and Vα24 were 20%; Vα28 was the only restricted-clone gene with the SFR of 10%. In all the Vβ genes, Vβ7 and Vβ17 were the the highest expression genes, and their SFRs were both 60%. Vβ11 was near them with the SFR of 40%; the restricted clonal genes were Vβ18 and Vβ20, their SFRs were 10% and 20%, respectivley.

CONCLUSION

There are skewd genes in TCR Vα and TCR Vβ, which are probably relative to the onset of T1D.

Is frontloaded sputum microscopy an option in active tuberculosis case finding?

SETTING

Active tuberculosis (TB) case finding (ACF) in Phnom Penh, Cambodia using light-emitting diode fluorescence microscopy (FM).

OBJECTIVE

To evaluate the smear-positive yield of frontloaded (same-day) smear microscopy in ACF.

DESIGN

All presumptive TB cases screened through ACF were asked to provide three sputum specimens: two spot specimens on Day 1 and a morning specimen on Day 2 (spot-spot-morning, SSM). Laboratory technicians blinded to previous results read the smears using FM. We considered only SSM series with at least one positive smear to calculate the proportion of TB cases missed and to determine the difference between the spot-spot (SS) and spot-morning (SM) approach.

RESULTS

Of 4616 presumptive TB patients enrolled, 3306 provided three sputum samples. Of 2957 (89.4%) who followed the SSM approach, 188 (6.4%) were smear-positive: 177 on SM and 160 on SS. The incremental yield of the second sputum sample was 18.1% for SM vs. 9.4% for SS. Relative to any smear-positive case detected by SSM, 28/188 (14.9%, 95%CI 10.1-20.8) TB cases would be missed by SS vs. 11/188 (5.9%, 95%CI 3.0-10.2) by SM. The difference in the proportion of missed TB patients was 9.0% (P = 0.006).

CONCLUSION

ACF frontloaded sputum microscopy is inferior in terms of smear-positive yield: the SS approach would have missed a significant proportion of smear-positive TB.

Effects of Feeding Barley Naturally Contaminated with Fusarium Mycotoxins on Growth Performance, Nutrient Digestibility, and Blood Chemistry of Gilts and Growth Recoveries by Feeding a Non-contaminated Diet

The objectives of this study were to investigate the effects of feeding barley naturally contaminated with Fusarium mycotoxins on growth performance, vulva swelling, and digestibility of dry matter, organic matter, and crude protein of gilts and the recovery of gilts fed normal diets immediately after the exposure to contaminated diets by measuring growth performance and vulva swelling. In Exp. 1, four diets were prepared to contain 0%, 15%, 30%, or 45% contaminated barley containing 25.7 mg/kg deoxynivalenol and 26.0 μg/kg zearalenone. Sixteen gilts with an initial body weight (BW) of 33.3 kg (standard deviation = 3.0) were individually housed in a metabolism crate and assigned to 4 diets with 4 replicates in a randomized complete block design based on BW. During the 14-d feeding trial, individual BW and feed consumption were measured weekly and the vertical and horizontal lengths of vulva were measured every 3 d. From d 10, feces were collected by the maker-to-marker method for 4 d. Blood samples were collected on d 14. During the overall period, the average daily gain, average daily feed intake, and gain:feed of pigs linearly decreased (p<0.01) as the dietary concentration of contaminated barley increased. However, the digestibility of crude protein was linearly increased (p = 0.011) with the increasing amounts of contaminated barley. Increasing dietary Fusarium mycotoxin concentrations did not influence vulva size, blood characteristic as well as immunoglobulin level of pigs. In the Exp. 2, a corn-soybean meal-based diet was formulated as a recovery diet. Pigs were fed the recovery diet immediately after completion of the Exp. 1. During the 14-d of recovery period, the individual BW and feed consumption were measured weekly and the vertical and horizontal length of vulva were measured every 3 d from d 0. On d 7, the feed intake of pigs previously fed contaminated diets already reached that of pigs fed a diet with 0% contaminated barley and no significant difference in growth performance among treatments was observed during d 7 to 14 of the recovery period. In conclusion, increasing levels of mycotoxins in diets linearly decreased the growth performance of pigs, and these damages can be recovered in 7 d after the diet was replaced with a normal diet. The vulva size, blood characteristic, immune responses were not affected by increasing level of contaminated barley in the diets fed to pigs.

Comparison of Oven-drying Methods for Determination of Moisture Content in Feed Ingredients

An accurate assessment of moisture content in feed ingredients is important because moisture influences the nutritional evaluation of feedstuffs. The objective of this study was to evaluate various methods for moisture content determination. In Exp. 1, the weight loss on drying (LOD) of corn, soybean meal (SBM), distillers dried grains with solubles (DDGS), whey permeate, whey powder, spray-dried porcine plasma (SDPP), fish meal, and a mixed diet of these 7 ingredients were measured by oven drying at 135°C for 2 h. Additionally, the samples were dried at 105°C for 3, 6, 9, 12, or 15 h. The LOD contents of the DDGS, whey permeate, and whey powder measured by drying at 135°C for 2 h were greater than the values measured by drying at 105°C for 3 h (p<0.05). All samples except SDPP (p = 0.70) dried at 105°C for 6, 9, 12, or 15 h caused more LOD compared with the samples dried for at 105°C for 3 h (p<0.05). The LOD contents of the individual ingredients were additive when dried at 105°C regardless of drying time. In Exp. 2, moisture contents of corn, SBM, wheat, whey permeate, whey powder, lactose, and 2 sources of DDGS (DDGS1 and DDGS2) were measured by the Karl Fischer method, oven drying at 135°C for 2 h, and oven drying at 125°C, 115°C, 105°C, or 95°C for increasing drying time from 1 to 24 h. Drying samples at 135°C for 2 h resulted in higher moisture content in whey permeate (7.5% vs 3.0%), whey powder (7.7% vs 3.8%), DDGS1 (11.4% vs 7.5%), and DDGS2 (13.1% vs 8.8%) compared with the Karl Fischer method (p<0.05). Whey permeate and whey powder were considerably darkened as the drying time increased. In conclusion, drying samples at 135°C for 2 h is not appropriate for determining the moisture content in whey permeate, whey powder, or DDGS as well as the mixed diet containing these ingredients. The oven-drying method at 105°C for 5 to 6 h appears to be appropriate for whey permeate and whey powder, and at 105°C for 2 to 3 h for DDGS.

Ileal Endogenous Amino Acid Flow Response to Nitrogen-free Diets with Differing Ratios of Corn Starch to Dextrose in Pigs

The objective of this study was to determine the responses in the digestibility of dry matter (DM) and amino acid (AA) composition of ileal endogenous flow (IEF) of pigs (initial body weight, 69.1±6.46 kg) fed N-free diets (NFD) formulated with different ratios of corn starch to dextrose. Fifteen pigs fitted with a T-cannula at the distal ileum were fed 5 diets according to a triplicated 5×2 incomplete Latin-square design. Each period consisted of a 5-d adjustment period and 2 d of ileal digesta collection for 12 h on each of d 6 and 7 and between each period, there was a 5-d recovery period to avoid abnormal weight loss. The ratios of corn starch to dextrose investigated were 0:879, 293:586, 586:293, 779:100, and 879:0 for diet numbers 1, 2, 3, 4 and 5, respectively, and chromic oxide (5 g/kg) was used as an indigestible index. Ileal DM digestibility was greater in Diet 1 than that in Diet 4 (89.5% vs 87.3%, p<0.01) but they were not different from Diet 2, 3, or 5. The IEF for most of indispensable AA were not different among diets with the exception of Met, in which a lack of corn starch or dextrose gave lower (p = 0.028) IEF of Met than diets containing corn starch and dextrose. Likewise, the dispensable AA and total AA in the IEF did not differ among diets. The respective IEF of AA (mg/kg of dry matter intake) in pigs fed Diets 1, 2, 3, 4, or 5 were 301, 434, 377, 477,or 365 for Lys, 61, 89, 71, 87, or 61 for Met, and 477, 590, 472, 520, or 436 for Thr. Proline was the most abundant AA in the IEF followed by Gly, Glu, and Asp and together accounted for approximately 50% of the total ileal AA flows of pigs fed NFD. In conclusion, the variation in proportion of corn starch and dextrose in a NFD does not largely affect estimates of IEF of N and AA for growing-finishing pigs.

Ileal digestibility of amino acids in meat meal and soybean meal fed to growing pigs

The objective of this experiment was to determine the concentration and digestibility of crude protein (CP) and amino acid (AA) in meat meal (MM), and to compare these values with the respective values in soybean meal (SBM). Six barrows (initial body weight = 66.9±3.8 kg) surgically fitted with a T-cannula at the distal ileum were allotted to a replicated 3×3 balanced Latin square design with 3 diets and 3 periods. Two experimental diets containing test ingredients as the sole source of AA were prepared to estimate the apparent ileal digestibility (AID) for CP and AA by the direct method. An N-free diet was also prepared to estimate basal endogenous losses of CP and AA. All experimental diets contained 5% chromic oxide as an indigestible index. Each period consisted of a 5-d adaptation period and a 2-d of ileal digesta collection period. Ileal digesta samples were collected from 0900 to 1700 on d 6 and 7 of each period. The concentrations of CP, Lys, Met, and Trp in MM and SBM were analyzed to be 64.1, 3.5, 1.1 and 0.6, and 45.6, 2.8, 0.8, and 0.3%, respectively. The AID of all AA except Gly in MM was less (p<0.05) than in SBM. The AID of Lys, Met, and Trp in MM was estimated to be 56.0, 71.7, and 47.1%, respectively. The SID of all AA in MM was less (p<0.05) than in SBM. The SID of Lys, Met, and Trp was 65.1, 79.2, and 78.5%, respectively. In conclusion, the CP and AA contents in MM were greater than those in SBM whereas the ileal digestibility of all AA in MM was less than in SBM.

Evaluation of amino Acid and energy utilization in feedstuff for Swine and poultry diets

An accurate feed formulation is essential for optimizing feed efficiency and minimizing feed cost for swine and poultry production. Because energy and amino acid (AA) account for the major cost of swine and poultry diets, a precise determination of the availability of energy and AA in feedstuffs is essential for accurate diet formulations. Therefore, the methodology for determining the availability of energy and AA should be carefully selected. The total collection and index methods are 2 major procedures for estimating the availability of energy and AA in feedstuffs for swine and poultry diets. The total collection method is based on the laborious production of quantitative records of feed intake and output, whereas the index method can avoid the laborious work, but greatly relies on accurate chemical analysis of index compound. The direct method, in which the test feedstuff in a diet is the sole source of the component of interest, is widely used to determine the digestibility of nutritional components in feedstuffs. In some cases, however, it may be necessary to formulate a basal diet and a test diet in which a portion of the basal diet is replaced by the feed ingredient to be tested because of poor palatability and low level of the interested component in the test ingredients. For the digestibility of AA, due to the confounding effect on AA composition of protein in feces by microorganisms in the hind gut, ileal digestibility rather than fecal digestibility has been preferred as the reliable method for estimating AA digestibility. Depending on the contribution of ileal endogenous AA losses in the ileal digestibility calculation, ileal digestibility estimates can be expressed as apparent, standardized, and true ileal digestibility, and are usually determined using the ileal cannulation method for pigs and the slaughter method for poultry. Among these digestibility estimates, the standardized ileal AA digestibility that corrects apparent ileal digestibility for basal endogenous AA losses, provides appropriate information for the formulation of swine and poultry diets. The total quantity of energy in feedstuffs can be partitioned into different components including gross energy (GE), digestible energy (DE), metabolizable energy (ME), and net energy based on the consideration of sequential energy losses during digestion and metabolism from GE in feeds. For swine, the total collection method is suggested for determining DE and ME in feedstuffs whereas for poultry the classical ME assay and the precision-fed method are applicable. Further investigation for the utilization of ME may be conducted by measuring either heat production or energy retention using indirect calorimetry or comparative slaughter method, respectively. This review provides information on the methodology used to determine accurate estimates of AA and energy availability for formulating swine and poultry diets.

Impacts of trace carbon on the microstructure of as-sintered biomedical Ti-15Mo alloy and reassessment of the maximum carbon limit

The formation of grain boundary (GB) brittle carbides with a complex three-dimensional (3-D) morphology can be detrimental to both the fatigue properties and corrosion resistance of a biomedical titanium alloy. A detailed microscopic study has been performed on an as-sintered biomedical Ti-15Mo (in wt.%) alloy containing 0.032 wt.% C. A noticeable presence of a carbon-enriched phase has been observed along the GB, although the carbon content is well below the maximum carbon limit of 0.1 wt.% specified by ASTM Standard F2066. Transmission electron microscopy (TEM) identified that the carbon-enriched phase is face-centred cubic Ti2C. 3-D tomography reconstruction revealed that the Ti2C structure has morphology similar to primary α-Ti. Nanoindentation confirmed the high hardness and high Young's modulus of the GB Ti2C phase. To avoid GB carbide formation in Ti-15Mo, the carbon content should be limited to 0.006 wt.% by Thermo-Calc predictions. Similar analyses and characterization of the carbide formation in biomedical unalloyed Ti, Ti-6Al-4V and Ti-16Nb have also been performed.

Energy value of distillers dried grains with solubles and oilseed meals for pigs

The energy values of 3 distillers dried grains with solubles (DDGS) derived from corn, triticale, and sorghum and 3 oil seed meals including canola meal (CM), cottonseed meal (CSM), and sunflower meal (SFM) were determined in 2 experiments. For both of experiments, 24 crossbred barrows (initial BW: 28.0 ± 1.60 and 28.0 ± 2.0 kg for Exp. 1 and 2, respectively) were grouped by weight into 6 blocks and placed in a metabolism crate with 1 pig per crate. There were 4 diets in each experiment consisting of a corn-soybean meal reference diet and 3 test diets. The test diet consisted of each of 3 DDGS (Exp. 1) or 3 oil seed meals (Exp. 2) that partly replaced the energy yielding sources in the reference diet at 300 (Exp. 1) or 200 g/kg (Exp. 2) such that same ratios were maintained for all energy ingredients across all experimental diets. The DE, apparent ME (AME), and N-corrected AME (AMEn) of the test ingredients were determined by the difference method in 2 experiments each consisting of a 5-d adjustment and 5 d of total but separate collection of feces and urine. The respective DM or GE of corn DDGS, triticale DDGS, sorghum DDGS, CM, CSM, and SFM were 918, 927, 904, 912, 907, and 898 g/kg or 5,429, 5,298, 5,295, 5,063, 5,327, and 4,589 kcal/kg of DM. Addition of DDGS to reference diet in Exp. 1 decreased (P < 0.01) dietary DE, AME, and AMEn of the test diet. However, in Exp. 2, the respective energy values of the test diet were not affected by the addition of oil seed meals to reference diet except for SFM, which decreased (P < 0.01) the energy values. The respective DE, AME, and AMEn were 3,751, 3,559, and 3,361 kcal/kg of DM for corn DDGS, 3,720, 3,537, and 3,315 kcal/kg of DM for triticale DDGS, and 3,520, 3,355, and 3,228 kcal/kg of DM for sorghum DDGS. There was no difference in any of energy values among 3 DDGS evaluated in the current study. Furthermore, the respective DE, AME, and AMEn were 3,577, 3,428, and 3,087 kcal/kg of DM for CM and 3,281, 3,139, and 2,892 kcal/kg of DM for CSM, which were greater (P < 0.01) than those for SFM at 2,449, 2,253, and 2,071 kcal/kg of DM. In conclusion, the DE, AME, AMEn evaluated by difference method in the current experiment was not different among 3 DDGS derived from corn, triticale, and sorghum whereas the respective energy concentration was less in SFM than those in CM and CSM.

Additivity of amino acid digestibility in corn and soybean meal for broiler chickens and White Pekin ducks

A total of 256 broiler chickens and 208 White Pekin ducks were used in a 5-d trial to test additivity of the apparent (AID) and standardized ileal digestibility (SID) of amino acids (AA) in corn and soybean meal (SBM). A nitrogen-free diet was used for standardization of apparent digestibility. Two diets contained corn or SBM as the sole source of CP and AA. Another diet was prepared by mixing corn and SBM. Chromic oxide was included as an indigestible marker. Birds received a standard starter diet from d 1 to 21 and thereafter the 4 experimental diets for 5 d in a randomized complete block design. On d 26, digesta from the distal section of the ileum was collected. To test additivity of digestibility values, the difference between measured values in mixed diet and predicted values calculated with measured values in individual ingredients was examined. The estimated basal endogenous losses of N and AA were higher in ducks compared with broilers (P < 0.05). Regardless of species, the calculated proportion of basal endogenous losses of CP and AA in calculating SID was higher (P < 0.01) in corn than that in SBM. The measured AID of His, Leu, Lys, Met, Phe, Glu, Pro, and Tyr in mixed diets for broilers were higher than predicted values (P < 0.05), whereas measured and predicted SID did not differ except for Cys. For ducks, the differences between the measured and predicted AID were significant (P < 0.05) for CP and all AA except for 8 AA (Arg, Ile, Thr, Val, Asp, Gly, Pro, and Tyr). Similar to the result from broiler study, there was no difference between the predicted and measured SID of CP and all AA except for Cys. The results showed that AID of some AA for corn and SBM were not additive in the mixed diet, but SID values were additive irrespective of the ingredients and species used. Moreover, extent of difference between measured and predicted values in ducks were higher than that in broilers.

Comparative amino acid digestibility for broiler chickens and White Pekin ducks

A total of 608 three-week-old male broiler chickens and White Pekin ducks were used in a 5-d trial to compare ileal amino acid (AA) digestibility of soybean meal (SBM) and canola meal (CM) using the regression method. A corn-casein-cornstarch-based diet was mixed to contain 15% CP. Cornstarch was replaced with test ingredient (SBM or CM) to contain 18 or 21% of CP in 4 other diets. A nitrogen-free diet (NFD) was used for standardization of apparent digestibility. Birds received a standard starter diet (23% CP) from d 0 to 14 posthatch and then 6 experimental diets for 5 d. On d 19 posthatch, birds were asphyxiated with CO(2), and digesta from the distal section of ileum was collected. The ileal digestibility of AA from the test ingredients was assessed by multiple linear regression analysis using data on daily apparent ileal digestible AA and total AA intakes. The basal endogenous losses of N and all AA for ducks were significantly higher than those for broilers. For ileal AA digestibility by regression of apparent digestible AA intake against AA intake, there was a higher (P < 0.05) digestibility for Cys and Pro in ducks compared with broilers (P < 0.05). Within species, digestibility was not different between SBM and CM except for Lys of ducks, and Lys and Pro of broilers (P < 0.05). The results of this study showed that ducks have higher basal endogenous AA losses compared with broiler chickens as well as higher ileal Cys and Pro digestibility estimates derived from regression approach, indicating that data obtained from broilers should not be used to formulate diets for ducks.