Spectrum of cutaneous granulomatous lesions: A 5-year experience in a tertiary care centre in Sarawak.

INTRODUCTION: Granulomatous skin lesions can have various histopathological features leading to diagnostic confusion. The study aimed to determine the frequency and pattern of different granulomatous skin lesions. MATERIALS AND METHODS: This was a 5-year retrospective study done between April 2017 and March 2022 at Dermatology Department, Sarawak General Hospital. Subjects with a clinicopathological diagnosis of granulomatous diseases were included in the analysis. RESULTS: A total of 1718 skin biopsies were done during the study periods, with 49 (2.8%) confirmed granulomatous skin lesions. Most patients were aged 40-60 with a male predominance of 51%. Most of the skin biopsy samples were taken from the upper limb (36%). In this study, epitheloid granuloma was the commonest subtype (21, 43%) followed by suppurative granuloma (12, 24%), tuberculoid granuloma (8, 16%) and foreign body granuloma (5, 10%). The commonest aetiology of granulomatous skin lesions in our study was infections (30, 61%) followed by foreign body inoculation (8, 16%). Fungal infection was the most common infective cause, followed by cutaneous tuberculosis. CONCLUSION: The major cause of granulomatous dermatoses in developing countries is still infections, fungal and tuberculosis being the leading causes.

[The association between the whole blood riboflavin level and the occurrence, development and prognosis of esophageal squamous cell carcinoma].

Objective: To investigate the association between the whole blood riboflavin level and the occurrence, development and prognosis of esophageal squamous cell carcinoma (ESCC) in China. Methods: From March 2014 to September 2018, ESCC patients from three hospitals (the Affiliated Hospital of Medical College of Shantou University, Shantou Central Hospital in Southern Chaoshan area and First Affiliated Hospital of Zhengzhou University in Northern Taihang Mountain) were selected as a case group; non-esophageal patients who had a physical examination were selected as a control group. The case and control group were paired by age (±5 years) and a 1:1 ration. A total of 1 528 subjects were enrolled including 764 patients in the case group and 764 patients in the control group. About 3-5 ml venous blood samples were collected, and the erythrocyte glutathione reductase activity coefficient (GRAC) was measured to assess the whole blood riboflavin level. A multivariate conditional logistic regression model was used to analyze the association between the GRAC and the risk of ESCC. The association between the GRAC and the prognosis of ESCC was analyzed by using Cox proportional risk regression model based on 288 patients with complete survival data. They were divided into two groups, the high GRAC group (GRAC≥7.87) group and the low GRAC group (GRAC<7.87) according to the strongest correlation between the total survival time, survival outcome and GRAC (GRAC=7.87). Results: Among the 1 528 patients, 958 patients were from Southern Chaoshan area, including 479 patients in the case group with an average age about (59.90±9.34) years and 479 patients in the control group with an average age about (59.55±8.77) years. Other 570 patients were from Northern Taihang Mountain area, including 285 patients in the case group with an average age (58.39±5.19) years and 285 patients in the control group with an average age about (58.74±4.57) years. The multivariate conditional logistic regression showed that the OR (95%CI) of the GRAC and the risk of ESCC was 1.009 (0.998-1.019). The Cox proportional hazard regression model analysis showed that the HR (95%CI) of the high GRAC group was 1.712 (1.034-2.824) compared with the low GRAC group in the 50-70 years group. Conclusion: The whole blood riboflavin level might not be associated with the occurrence of ESCC. The high whole blood riboflavin level would be more beneficial to the prognosis of ESCC patients aged 50-70 years.

Infections in hospitalized lupus nephritis patients: characteristics, risk factors, and outcomes.

Background There are limited studies documenting infection epidemiology in lupus nephritis (LN) patients. We aimed to study infection incidences and risk characteristics and ascertain possible predictors of infective outcomes in a multiethnic Asian population. Methods This retrospective study from 2006 to 2012 included newly diagnosed LN patients. We collected admissions, immunosuppression, and infection data until end-stage renal failure, death, last follow-up, or the year 2015. The infection incidence rates were evaluated and a generalized linear latent and mixed models (GLLAMM) analysis was carried out to evaluate potential predictors of infection. Results Our cohort of 101 patients consisted of mainly Chinese (75.2%), females (78.2%), and a median age of 38 years (IQR 26-49). The median time of follow-up was 72.8 months (IQR 49.5-94.0). Six out of 14 patient deaths were infection related. Seventy-eight out of 200 admissions, with a total of 102 episodes of infection, occurred in 46 patients. The incidence of infection rates leading to admissions was 10.3 per 100 person-years and the incidence of infection episodes rates was 17.6 per 100 person-years. Cytomegalovirus (CMV) was the most common organism identified. Univariate GLLAMM analysis showed Malay compared to Chinese ethnicity (HR 2.833 (95% CI 1.088-7.373)), use of oral cyclophosphamide (HR 6.618 (95% CI 1.015-43.154)) and rituximab (HR 3.967 (95% CI 1.157-13.603)) as predictors of infection-related admissions. Malay ethnicity and rituximab remained significant in the multivariate GLLAMM analysis. Conclusions Our study highlights substantial infection incidences in patients with LN and its contribution to deaths.

Effect of skeletal muscle fibers on porcine meat quality at different stages of growth.

In this study, we examined changes in meat quality and content of muscle types during porcine growth. The influence of the longissimus dorsi muscle fiber composition on meat quality and the correlation between 2 fiber-typing methods (histochemistry and real-time quantitative polymerase chain reaction) were examined. Type IIx and type IIb fibers accounted for most of the total number of fibers; the proportion of these fibers increased during porcine growth (75.42, 80.09, and 79.88%, respectively, at 3 different stages of growth). There was a strong positive correlation between the 2 fiber-typing methods; the correlation coefficients of type I, IIa, and IIx+IIb fiber contents were 0.65, 0.88, and 0.92, respectively. The a* value of meat color was significantly lower at 98 days and negatively correlated with white fiber content (r = -0.69, P < 0.01). Water-holding capacity decreased during porcine growth. The drip loss parameter was positively correlated with type IIx+IIb fiber content (r = 0.55, P < 0.05). Decreased pH was strongly positively correlated with type IIx+IIb fiber content (r = 0.61, P < 0.01) and negatively correlated with type IIa fiber content (r = -0.44, P < 0.05). Therefore, we found that the composition of muscle fibers influenced the establishment of meat quality and its alteration during the early postmortem period.

Synthesized prevention and control of one decade for mother-to-child transmission of syphilis and determinants associated with congenital syphilis and adverse pregnancy outcomes in Shenzhen, South China.

The purpose of this investigation was to assess the effectiveness of an intervention program on mother-to-child transmission (MTCT) of syphilis and investigate determinants of congenital syphilis (CS) and adverse pregnancy outcomes (APOs). The Shenzhen local government initiated an intervention program of MTCT of syphilis in 2001. Based on this program, maternal and paternal factors associated with CS and APOs among syphilitic women were investigated from 2007 to 2012 by a prospective cohort study. From 2002 to 2012, 2,441,237 pregnant women were screened and screening coverage reached 97.2 % in 2012. In the background of continuing growth of CS in China, CS in Shenzhen significantly decreased from 109.3 cases in 2002 to 9.9 cases in 2012 per 100,000 live births. Maternal education (adjusted odds ratio [aOR]CS = 0.65; aORAPOs = 0.79) and history of syphilis (aORCS = 0.28; aORAPOs = 0.61), as well as paternal age (aORCS = 0.62; aORAPOs = 0.86) and education (aORCS = 0.66; aORAPOs = 0.86) were negatively associated with CS and APOs, but maternal unmarried status (aORCS = 1.95; aORAPOs = 2.61), inadequate antenatal care (ANC) (aORCS = 3.61; aORAPOs = 1.79), more sexual partners (aORCS = 1.51; aORAPOs = 1.39), every week of delay in treatment (aORCS = 2.82; aORAPOs = 1.27), higher baseline titers of nontreponemal antibodies (aORCS = 5.65; aORAPOs = 1.47), early syphilis (aORCS = 23.24; aORAPOs = 26.95), and non-penicillin treatment (aORCS = 3.00; aORAPOs = 2.16), as well as paternal history of cocaine use (aORCS = 2.70; aORAPOs = 2.44) and positive (aORCS = 4.14; aORAPOs = 1.50) or unknown (aORCS = 2.37; aORAPOs = 2.06) status of syphilis increased the risk of CS and APOs. Condom use (aOR = 0.70) decreased MTCT of syphilis. A ten-year program consisting of screening and treatment, early ANC, health education, partners tracking, detection, and treatment, follow-up visits, and information management is an effective means to block MTCT of syphilis. Maternal and paternal factors constituted two separate profiles associated with MTCT of syphilis.

Effects of outdoor access on growth performance, carcass composition, and meat characteristics of broiler chickens.

The present study was conducted to investigate the effects of outdoor access on the growth performance and meat quality of broiler chickens. Thirty-five-day-old female broilers were divided into 3 groups with 6 replicates of 124 birds each: (1) birds reared indoors (control group); (2) birds reared with outdoor access since 36 d of age (35-d group); and (3) birds reared with outdoor access since 71 d of age (70-d group). The results showed that outdoor access had no effect on growth performance, carcass yield, meat yield, muscle protein content, muscle fiber characteristics, or water-holding capacity (P > 0.05). Chickens from the outdoor access groups had a better appearance and degree of evenness. Birds in the outdoor access groups had a significantly lower lung percentage than birds in the control group (P < 0.05), whereas the kidney percentage of the 35-d group was significantly lower than that of the control group (P < 0.05). The meat of chickens in the 35-d group had higher L* values than that of the control group (P < 0.05). Compared with rearing indoors, outdoor access significantly increased the shear force of the breast muscle in both the 35 d and 70-d group (P < 0.05) and decreased the fat content of the thigh muscle in the case of 35-d group (P < 0.05). Birds in the 35-d group also had lower fat content in their thigh muscles than did the birds in the 70-d group (P < 0.05). The thigh muscles of the birds in the 35-d group showed lower levels of MUFA and higher levels of PUFA than those of the control group and 70-d group (P < 0.05). In conclusion, outdoor access had no effect on growth performance and yield traits but could improve the meat quality; birds reared with outdoor access from 36 d of age had better appearance and meat quality than those with outdoor access from 71 d of age.

Nutrient density and slaughter age have differential effects on carcase performance, muscle and meat quality in fast and slow growing broiler genotypes.

1. A 2 × 2 factorial design was used to investigate the differences in carcase, muscle and meat characteristics between fast and slow growing genotypes fed on low nutrient (LND) or high nutrient diets (HND) at their respective slaughter ages. 2. The birds were randomly assigned to treatments with 5 replicates of 145 birds for Wens Yellow-Feathered Chicken (WYFC, 5·75 birds/m(2)) or 115 birds for White Recessive Rock Chicken (WRRC, 7·25 birds/m(2)), according to the commercial recommendations for the two breeds and were fed on HND or LND. Birds were slaughtered at 63 d and 105 d of age. 3. The results showed WRRC had higher carcase yield and meat yield than that of WYFC, lower fat content, higher moisture content and lower cooking loss. The meat from WRRC was less tender and contained lower levels of polyunsaturated fatty acids (PUFA). 4. Birds fed on HND had higher breast meat yield, myofiber area and protein content in the breast muscle and lower fat content than birds fed on LND. The thigh muscle of birds fed on HND had higher levels of PUFA. Age had a positive effect on carcase parameters, but a negative effect on pH, meat tenderness and cooking loss, and the two genotypes exhibited different responses to the influence of nutrient density and age. 5. Genotype and age had the largest effect on carcase performance and meat quality. LND benefited meat quality and WRRC had larger responses in meat yield and shear force when fed on HND.

Effects of breed and dietary nutrient density on the growth performance, blood metabolite, and genes expression of target of rapamycin (TOR) signalling pathway of female broiler chickens.

This study was conducted to compare the effects of exchanged diets with identical energy level on characteristics of slow-growing (WENs Yellow-Feathered Chicken, WYFC) and fast-growing (White Recessive Rock Chicken, WRRC) female chickens. A total of 1450 WYFC and 1150 WRRC 1-day-old female hatchlings were used. A high-nutrient-density (HND) diet and a low-nutrient-density (LND) diet were formulated for three phases. A completely randomized experimental design with a 2 × 2 factorial arrangement (diet and breed), each with five replicates of 145 and 115 birds, was applied. The results showed that WRRC had a higher body weight (BW), average daily feed intake and average daily gain than WYFC throughout the experiment (p<.05). WYFC that were provided with HND groups had a higher BW only in the starter and grower phases, whereas WRRC had a higher BW in the HND group than in LND groups throughout the experiment. The feed:gain ratio and protein efficiency ratio (PER) were better for WRRC in the starter and grower phases; however, these ratios were better for WYFC in the finisher period. The LND groups had a higher PER throughout the experiment for both breeds (p<0.05). The breast and leg muscle weights were higher for WRRC compared with WYFC during the grower and finisher phases (p<0.05). WRRC had a lower liver index but higher serum UA and alkaline phosphatase (ALP) concentrations than WYFC (p<0.05). No diet effect was observed on organ indices, muscle yields or blood responses. The gene expressions of Rheb, TOR, S6K1 and 4E-BP1 in gastrocnemius muscle were the highest in the WYFC-LND groups at 63 and 105 days (p<0.05). These findings suggested that different genotypes respond differently to changes in dietary nutrient density and that lower-nutrient-density diets are optimal for the long-term housing of broiler chickens.

Using corn starch as basal diet to determine the true metabolizable energy of protein feedstuffs in Chinese Yellow chickens.

Two experiments were conducted to investigate the feasibility of using corn starch as the basal diet to determine the ME of protein feedstuffs using the TME assay in Chinese Yellow chickens. In the first experiment, the TME of corn starch were determined by force-feeding 25 or 40 g of feed. To test the repeatability of the bioassay, the same experiment was repeated 4 times. In the second experiment, the TME of soybean meal and cottonseed meal was determined by considering corn starch as the basal diet, while corn was fed alone to the chickens. To test the accuracy of the TME assay for individual ingredients, the additivity was evaluated by determining the TME of 3 mixed diets: corn-soybean meal diet, corn-cottonseed meal diet, and corn-soybean meal-cottonseed meal diet. In experiment 1, the value of endogenous energy loss was 16.76 to 18.46 kcal/48 h, and no significant differences between the 4 assays were noted. The TME and energy metabolizability of the 25-g corn starch treatment (4.06 kcal/g and 98.06%) were higher than those of the 40-g treatment (3.79 kcal/g and 91.45%; P < 0.01); whereas the CV were less than that of the 40-g treatment, indicating that it is reasonable to use the TME value of the 25-g treatment in feed formulation. In experiment 2, the TME values for corn, soybean meal, and cottonseed meal were 4.02, 3.39, and 2.92 kcal/g, respectively. The observed and predicted TME values of the corn-soybean meal, corn-cottonseed meal, and corn-soybean meal-cottonseed meal diets were in high agreement with differences ranging from -0.02 to 0.01 kcal/g. None of the differences was significant, indicating an accurate measure of the TME of the individual ingredients. Thus, using corn starch as the basal diet to determine the TME of protein feedstuffs was validated.

Effects of dietary protein source on the digestive enzyme activities and electrolyte composition in the small intestinal fluid of chickens.

An experiment was conducted to investigate the effects of dietary protein source on the digestive enzymes and electrolyte composition of digesta fluid in the duodenum, jejunum, and ileum of chickens. A 2 × 3 factorial and completely randomized design that used 2 types of diets that differed only in their protein source [a corn-soybean meal-miscellaneous meal diet (CSMD) and a corn-miscellaneous meal diet (CMD)] and 3 types of cannulated roosters (duodenal, jejunal, and ileal cannulations) was adopted. The experiments included 5 replicates for each of the 6 treatments, and each replicate involved 3 cannulated chickens. The digesta samples were collected for 1 h every 4 h between 09:30 and 18:30 h on d 31, 33, and 35 of the experiment. The amylase, lipase, trypsin, and chymotrypsin activities and the electrolyte composition in the duodenal, jejunal, and ileal fluid were determined. In general, no significant differences between the 2 dietary groups were observed for the mean of duodenal, jejuna, and ileal amylase, trypsin, chymotrypsin, and lipase, respectively. However, the duodenal amylase activity was lower in the CMD group than the CSMD group (P < 0.05), which was probably related to the lower duodenal pH value that was observed in this group (P < 0.01). A higher jejunal Mg(2+) concentration was observed in chickens that were fed the CMD (P < 0.05), whereas the differences in the Na(+), K(+), Cl(-), and Ca(2+) concentrations in the small intestine were not significant between the 2 diets (P > 0.05). In conclusion, the digestive enzymes and electrolytes in the small intestinal fluid of chickens adapted to the protein source of the diet, and each segment of the small intestine displayed different modifications.

[Morphological and molecular identification of trematode isloates from laying ducks in Nanchang City].

OBJECTIVE: To identify the species of trematodes isolated from laying ducks in Nanchang City using morphological and molecular approaches. METHODS: Trematodes were isolated from the hepatobiliary duct, gallbladder and large intestine of market-sold laying ducks in Nanchang City. Following morphological characterization, total DNA was extracted from all trematode specimens, and internal transcribed spacer region (ITS) and cytochrome C oxidase subunit 1 (Cox1) genes were amplified using PCR assay and sequenced. Sequence alignment was performed using the Blast software, and homology and phylogenetic analyses were done in the trematode isolates based on ITS and Cox1 gene sequences. RESULTS: The morphological characteristics of two trematode isolates from the large intestine of laying ducks were similar to those of Echinostoma revolutum and E. miyagawai, and the morphological characteristics of eight trematode samples isolated from the hepatobiliary duct and gallbladder of laying ducks were similar to those of Amphimerus anatis. The ITS and Cox1 gene sequences of the two trematode isolates from the large intestine of laying ducks had 99.3% and 98.9%-99.4% homology with E. miyagawai, and the phylogenetic analysis showed that two trematode isolates had the closest genetic relationship with E. miyagawai based on ITS and Cox1 gene sequences. The ITS gene sequences of eight trematode isolates from the hepatobiliary duct and gallbladder of laying ducks shared 95.1%-95.5% with Opisthorchis sudarikovi and Clonorchis sinensis, while the Cox1 gene sequences of eight trematode isolates from the hepatobiliary duct and gallbladder of laying ducks shared 86.3%-86.4% and 85.5%-85.7% with O. viverrini and O. sudarikovi. ITS gene sequence-based phylogenetic analysis showed that the duck-derived trematode isolates had the closest genetic relationship with C. sinensis, and Cox1 gene sequence-based phylogenetic analysis showed that the duck-derived trematode isolates had the closest genetic relationship with Metorchis orientalis and O. viverrini. CONCLUSIONS: The trematode isolates from the large intestine of laying ducts in Nanchang City may be E. miyagawai, and the trematode isolates from the hepatobiliary duct and gallbladder may be an unidentified trematode species of the family Opisthorchiidae.

Comparison of amino acid digestibility and its additivity determined with slaughter or cecectomy method for yellow-feather chicken.

The objective of this experiment was to compare the slaughter and cecectomy methods to determine amino acid (AA) digestibility of corn and soybean meal and their additivity in a corn-soybean meal diet. A completely randomized design was adopted to determine endogenous AA losses (EAAL) and AA digestibility in each of corn, soybean meal, and a corn-soybean meal diet using either slaughter or cecectomy methods. Each treatment contained 6 replicates with 3 chickens per replicate. The endogenous loss (EL) of histidine and glycine was lower and the EL of methionine and phenylalanine was greater when determined by slaughter vs. cecectomy (P < 0.05). The EL of arginine, isoleucine, leucine, lysine, methionine, phenylalanine, valine, alanine, aspartic acid, glutamic acid, and serine determined by slaughter were 1.2 to 3.2 times of those from cecectomy. The standard error (SE) of EL of 14 AA (excluding histidine and glycine) obtained by slaughter method was 2.1 to 9.6 times of those by cecectomy method. The apparent and standardized digestibility was not affected by methods for most AA except apparent digestibility of methionine, phenylalanine and glycine, and standardized digestibility of glycine in corn. The apparent and standardized digestibility of most AA except apparent digestibility of glycine and standardized digestibility of lysine, cysteine and glycine were less for slaughter versus cecectomy methods in soybean meal (P < 0.05). Using slaughter method resulted in reduced apparent digestibility of 15 AA (except glycine) and reduced standardized digestibility of 7 AA (arginine, isoleucine, leucine, valine, aspartic acid, glutamic acid, and proline) relative to cecectomy method (P < 0.05), but the standardized digestibility of glycine was greater when determined by slaughter vs. cecectomy methods in corn-soybean meal diet (P < 0.05). The mean value of SE of 16 AA digestibility in slaughter method was 2.9 times of that by cecectomy method. The apparent digestibility of 2 and 9 of 16 AA and the standardized digestibility of 15 and 7 of 16 AA were additive when using slaughter and cecectomy determinations, respectively. In conclusion, compared to the slaughter method, cecectomy method had less SE and EAAL but greater apparent digestibility of methionine and phenylalanine in corn, and the apparent digestibility of 15 AA (except glycine) in soybean meal and corn-soybean meal diet. Additivity in apparent and standardized AA digestibility was more inconsistent when determined with slaughter vs. cecectomy methods. These findings suggest that the cecectomy method is more suitable than the slaughter method to determine the digestibility of AA.

[Comparison of training models for master of public health between China and other countries].

With the accelerating globalization and the implementation of "Belt and Road" initiative proposed by our government, communication and exchanges between China and foreign countries have become more and more frequent than before, and much more international students have chosen to study in China's universities as candidates of master of public health (MPH). However, because China only launched the MPH program in recent years, with the training models being highly similar to the program of master of science in China but quite different from those of main international MPH programs, hindering China's MPH program to become an international one. This paper systematically evaluated existing training models of MPH programs both at home and abroad through literature review and identified major differences and deficiencies of China's MPH program compared to those from other countries: (1) requirement for medical background only; (2) comparatively longer period to complete the program; (3) incomplete curriculum; (4) overemphasizing scientific research competencies but somewhat neglecting practical abilities; and (5) limited career choices, and put forward some suggestions to improve the MPH program of China, including removing requirement for medical background only, shortening the period of MPH program, improving the curriculum of MPH program, and enhancing the training of practical abilities.

[Machine learning and its epidemiological applications].

As an important branch of artificial intelligence, machine learning is widely used in various fields. Machine learning has similarity to classical statistical methods, but can solve many problems which are difficult for traditional statistics, so it is one of the important tools in epidemiological research. This paper introduced 9 common algorithms of machine learning and summarized their characteristics and applications in epidemiological research. Readers could choose appropriate machine learning method according to the research purpose for the better application of machine learning in epidemiological research.

Sensitivity of in vitro digestible energy determined with computer-controlled simulated digestion system and its accuracy to predict dietary metabolizable energy for roosters.

Two experiments were conducted to validate the sensitivity and accuracy of in vitro digestible energy (IVDE) determined with a computer-controlled simulated digestion system (CCSDS) to predict metabolizable energy (ME) of diets for roosters. In experiment 1, soybean hulls were added to a basal diet (calibration diet 1) at 2.06, 4.12, 6.17, 8.23, 10.28, 12.32, or 14.37% of the diets (calibration diets 2-8) to produce an interval of approximately 80 kcal ME/kg. The sensitivity was measured by comparing the determined and actual IVDE of the diets. With these data, a linear model was developed to predict ME from IVDE. In experiment 2, validation diets were identical except they were composed of different cereal ingredients. For each diet, the correlations and ratios between IVDE and ME were analyzed to test the sensitivity of IVDE to predict ME across different ingredients. In experiment 1, a slope of 0.9899 was calculated in a linear regression of determined IVDE on actual IVDE (R2 = 0.9998; P < 0.01). The ratio of determined IVDE to actual IVDE was 0.9878. The ratio of IVDE to apparent metabolizable energy (AME) and to nitrogen-corrected AME (AMEn) was 1.03 and 1.05, respectively. The linear models to predict ME from IVDE were AME = 0.8449 × IVDE + 451 (R2 = 0.9812, residual standard deviation [RSD] = 28 kcal/kg; P < 0.01) and AMEn = 0.8357 × IVDE + 436 (R2 = 0.9821, RSD = 27 kcal/kg; P < 0.01). In experiment 2, a significant simple correlation was observed between the IVDE and AME or AMEn of validation diets (r > 0.97; P < 0.01). The ratio of IVDE to AME and to AMEn was 1.04 and 1.05, respectively. Predicted and determined AME or AMEn of 8 validation diets differed by less than 100 kcal/kg. The regression of determined AME or AMEn against predicted AME or AMEn (R2 ≥ 0.9466; P < 0.01) resulted in an overlapped line where Y = X. These results suggest the IVDE determined with CCSDS is highly sensitive and can be used to accurately predict the ME of diets for roosters across a wide range of cereal grains.

Research Note: Effect of dietary cottonseed meal and soybean oil concentration on digesta passage time and amino acids digestibility in roosters.

Two experiments were conducted to study the effect of dietary cottonseed meal (CM) and soybean oil (SO) on passage time of digesta and standardized ileal digestibility (SID) of amino acids (AA). The experimental design was a 2 × 2 factorial arrangement evaluating the levels of CM (20 or 40 %) and SO (0 or 10 %). Experiment 1 estimated the effect of CM and SO on the passage time of digesta. Twenty-five Chinese yellow-feathered roosters (BW = 2.61 ± 0.08 kg; 26-wk-old) were individually weighed and allocated to 5 diets in 5 randomized complete blocks by initial BW. Experimental diet 1 contained 20% CM and 0 SO, diet 2 contained 20% CM and 10% SO, diet 3 contained 40% CM and 0% SO, diet 4 contained 40% CM and 10% SO, and a nitrogen-free diet was also fed. Passage time through the total digestive tract was determined by time-relative cumulation of dry excreta. Experiment 2 estimated the effect of CM and SO on SID of AA in CM. Thirty Chinese yellow-feathered roosters (BW = 2.91 ± 0.05 kg; 26-wk-old) were allocated to the 5 experimental diets in 6 randomized complete blocks by initial BW to determine the SID of AA. Increasing CM concentration significantly reduced the time for 50% relative cumulation of dry excreta (P < 0.05). Adding 10% SO tended to increase the time for 50% relative cumulation of dry excreta (0.05 < P < 0.10) relative to diets without SO. Dietary CM and SO did not affect the SID of indispensable AA or dispensable AA of CM significantly, but increasing dietary CM tended to reduce the SID of Lys (0.05 < P < 0.10). Increasing SO tended to reduce the SID of Met (0.05 < P < 0.10). There were no significant interactive effects of SO and CM (P > 0.10). These results suggest passage time is increased with dietary SO, and reduced with dietary CM, but digestibility of AA in CM was not significantly affected by dietary CM and SO.

[An epidemiologic thinking on the diagnosis criteria of COVID-19].

The diagnosis of COVID-19 is based on the positive of etiological test. The current etiological test of COVID-19 cost long time, and have high false negative rate, may resulting delay the measures of disease treatment and prevention. We suggested that COVID-19 should be diagnosed as 3 types: suspected case, clinical diagnosed case, and definite diagnosed case.

[A sequential conditional mean model for assessing total effects of exposure in longitudinal data].

In prospective cohort study, multi follow up is often necessary for study subjects, and the observed values are correlated with each other, usually resulting in time-dependent confounding. In this case, the data generally do not meet the application conditions of traditional multivariate regression analysis. Sequential conditional mean model (SCMM) is a new approach that can deal with time-dependent confounding. This paper mainly summarizes the basic theory, steps and characteristics of SCMM.

Understanding the dynamics of COVID-19; implications for therapeutic intervention, vaccine development and movement control.

The COVID-19 disease is caused by the SARS-CoV-2 virus, which is highly infective within the human population. The virus is widely disseminated to almost every continent with over twenty-seven million infections and over ninety-thousand reported deaths attributed to COVID-19 disease. SARS-CoV-2 is a single stranded RNA virus, comprising three main viral proteins; membrane, spike and envelope. The clinical features of COVID-19 disease can be classified according to different degrees of severity, with some patients progressing to acute respiratory distress syndrome, which can be fatal. In addition, many infections are asymptomatic or only cause mild symptoms. As there is no specific treatment for COVID-19 there is considerable endeavour to raise a vaccine against SARS-CoV-2, in addition to engineering neutralizing antibody interventions. In the absence of an effective vaccine, movement controls of varying stringencies have been imposed. Whilst enforced lockdown measures have been effective, they may be less effective against the current strain of SARS-CoV-2, the G614 clade. Conversely, other mutations of the virus, such as the Δ382 variant could reduce the clinical relevance of infection. The front runners in the race to develop an effective vaccine focus on the SARS-Co-V-2 Spike protein. However, vaccines that produce a T-cell response to a wider range of SARS-Co-V-2 viral proteins, may be more effective. Population based studies that determine the level of innate immunity to SARS-CoV-2, from prior exposure to the virus or to other coronaviruses, will have important implications for government imposed movement control and the strategic delivery of vaccination programmes.