Reference Intervals for Reticulocyte Hemoglobin Content, Mean Reticulocyte Volume and Reticulocyte Count Percentage in Healthy Han Ethnic Adults of Chengdu.

BACKGROUND: The goals of this study are to determine the RIs of RHE, MRV, and reticulocyte count percentage (RET) in healthy Han ethnic adults of Chengdu. METHODS: A total of 691 Han adults without iron deficiency, aged 20 to 90 years were included in the study. The RIs were defined as mean ± 1.96 SD. RESULTS: After statistical analysis the RIs were 29.95 - 35.12 pg (RHE), 99.76 - 115.97 fL (MRV) in males and 29.77 - 34.52 pg (RHE), 98.72 - 113.83 fL (MRV) in females. RET reference interval was 0.485 - 1.504%. CONCLUSIONS: In our study, we established RHE, MRV, and RET RIs of the Han ethnic population in Chengdu for the first time.

Establishment of Reference Intervals for Serum Cytokeratin-19 Fragment and Neuron Specific Enolase by Indirect Method Using Data Obtained from Healthy Chinese Population in Chengdu.

BACKGROUND: In order to establish suitable reference intervals (RIs) of serum cytokeratin-19 fragment (Cyfra211) and neuron specific enolase (NSE) for the healthy Chinese population in Chengdu, China, an indirect method was developed using the data from the people presented for routine health check-up. METHODS: All results for 4,988 healthy persons serum cytokeratin-19 fragment and 3,293 healthy persons neuron specific enolase were collected in our laboratory information system between January 2016 and December 2018. Outliers were identified and excluded using the stem-and-leaf and box plot methods. Mann-Whitney U test was used to observe the difference between sexes. Spearman's rank correlation analysis was used to evaluate the correlation between serum results and age. The RIs were defined by nonparametric 95th percentile interval. RESULTS: After statistical analysis the indirect RIs were 0.0 - 3.70 ng/mL (Cyfra211) and 0 - 17.26 ng/mL (NSE) in males and 0.0 - 3.35 ng/mL (Cyfra211) and 0.0 - 16.29 ng/mL (NSE) in females. Cyfra211 and NSE levels in males and females had no correlation with age. Therefore, there was no need to establish RIs according to age group. RIs of Cyfra211 and NSE were verified and passed the verification in the end. CONCLUSIONS: Using health check-up persons' laboratory data values is a relatively easy and cheap method of establishing laboratory specific references. This method deserves to be promoted and applied by other clinical laboratories.

Identification of synthetic peptides that inhibit lipopolysaccharide (LPS) binding to myeloid differentiation protein-2 (MD-2).

Many studies have suggested that the synergic effect of myeloid differential protein-2 (MD-2) on bacterial lipopolysaccharide (LPS) stimulation of toll-like receptor 4 (TLR4) may be a critical step during the LPS-TLR4 response signaling pathway. We performed a bioinformatic analysis on the MD-2 protein and identified the amino acid sequence NH2-FSKGKYKCV-COOH (K128-132) as a possible key sequence involved in the binding between MD-2 and LPS. We then screened a random phage display peptide library using this sequence as bait in order to identify antagonistic peptides. After 3 rounds of selection, 3 positive clones were identified. All 3 peptides were shown to inhibit, in a dose-dependent manner the production of tumor necrosis factor-α and interleukin-6 in human U937 and THP-1 cell lines as well as human peripheral blood monocytes stimulated by LPS. Only 2 of the 3 peptides were able to bind MD-2 directly as shown by sulfo-SBED biotin label transfer experiments. BALB/C mice were used to estimate the protection of these peptides from LPS challenge, and 2 of the 3 peptides (Lys-Thr-Val-Pro-Asp-Asn-His and Ile-Gly-Lys-Phe-Leu-Tyr-Arg) reduced mortality of the challenged mice from 100% to 53.8%. This study has demonstrated that interfering with the binding between MD-2 and LPS might be a potential therapeutic strategy for treating LPS-induced sepsis, and in doing so has identified 2 potential peptide candidates.

[Heterogeneity changes in secretion ability of monocyte/macrophage and its significance after trauma hemorrhage in rat].

OBJECTIVE: To investigate the relationship between the heterogeneity in secretion ability of monocyte (Mo)/macrophage and the immune dysfunction after severe trauma. METHODS: Twenty-four healthy Wistar rats were randomly divided into normal control group and trauma hemorrhage 1, 4 and 7 days groups. The contents of interleukin-6 (IL-6) and IL-10 secretion of Mo/macrophage from different anatomical regions were determined by radioimmunoassay. RESULTS: (1)In normal rats, the ability to secrete IL-6 and IL-10 was different among alveolar macrophages (AM), peritoneal macrophages (PM) and Mo. PM showed the highest ability to secrete IL-10 while Mo had the highest ability to secrete IL-6. (2)After trauma hemorrhage, the secretion of IL-6 and IL-10 by AM were increased dramatically. On the contrary, the secretion of IL-6 by PM was declined from the 1st day to the 4th day, then increased even over that of the normal control group on the 7th day. However, the secretion of IL-10 by PM was significantly elevated on the 1st day after trauma hemorrhage, peaking on the 4th day, and only slight lowering was found on the 7th day. The secretion of IL-6 by Mo was declined gradually all the time, reaching the lowest point on the 7th day. On the contrary, the secretion of IL-10 by Mo was increasing, reaching its peak on the 7th day. CONCLUSION: The heterogeneity of secretion ability of Mo/macrophage obtained from different anatomical regions is present under normal condition, and is more obvious following a severe injury. This change may play an important role in the immune dysfunction and the development of complications after trauma.