Lactobacillus rhamnosus GG ameliorates hyperuricemia in a novel model.

Hyperuricemia (HUA) is a metabolic syndrome caused by abnormal purine metabolism. Although recent studies have noted a relationship between the gut microbiota and gout, whether the microbiota could ameliorate HUA-associated systemic purine metabolism remains unclear. In this study, we constructed a novel model of HUA in geese and investigated the mechanism by which Lactobacillus rhamnosus GG (LGG) could have beneficial effects on HUA. The administration of antibiotics and fecal microbiota transplantation (FMT) experiments were used in this HUA goose model. The effects of LGG and its metabolites on HUA were evaluated in vivo and in vitro. Heterogeneous expression and gene knockout of LGG revealed the mechanism of LGG. Multi-omics analysis revealed that the Lactobacillus genus is associated with changes in purine metabolism in HUA. This study showed that LGG and its metabolites could alleviate HUA through the gut-liver-kidney axis. Whole-genome analysis, heterogeneous expression, and gene knockout of LGG enzymes ABC-type multidrug transport system (ABCT), inosine-uridine nucleoside N-ribohydrolase (iunH), and xanthine permease (pbuX) demonstrated the function of nucleoside degradation in LGG. Multi-omics and a correlation analysis in HUA patients and this goose model revealed that a serum proline deficiency, as well as changes in Collinsella and Lactobacillus, may be associated with the occurrence of HUA. Our findings demonstrated the potential of a goose model of diet-induced HUA, and LGG and proline could be promising therapies for HUA.

Lipid metabolism-related long noncoding RNA RP11-817I4.1 promotes fatty acid synthesis and tumor progression in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common types of tumors. The influence of lipid metabolism disruption on the development of HCC has been demonstrated in published studies. AIM: To establish an HCC prognostic model for lipid metabolism-related long non-coding RNAs (LMR-lncRNAs) and conduct in-depth research on the specific role of novel LMR-lncRNAs in HCC. METHODS: Correlation and differential expression analyses of The Cancer Genome Atlas data were used to identify differentially expressed LMR-lncRNAs. Quantitative real-time polymerase chain reaction analysis was used to evaluate the expression of LMR-lncRNAs. Nile red staining was employed to observe intracellular lipid levels. The interaction between RP11-817I4.1, miR-3120-3p, and ATP citrate lyase (ACLY) was validated through the performance of dual-luciferase reporter gene and RIP assays. RESULTS: Three LMR-lncRNAs (negative regulator of antiviral response, RNA transmembrane and coiled-coil domain family 1 antisense RNA 1, and RP11-817I4.1) were identified as predictive markers for HCC patients and were utilized in the construction of risk models. Additionally, proliferation, migration, and invasion were reduced by RP11-817I4.1 knockdown. An increase in lipid levels in HCC cells was significantly induced by RP11-817I4.1 through the miR-3120-3p/ACLY axis. CONCLUSION: LMR-lncRNAs have the capacity to predict the clinical characteristics and prognoses of HCC patients, and the discovery of a novel LMR-lncRNAs, RP11-817I4.1, revealed its role in promoting lipid accumulation, thereby accelerating the onset and progression of HCC.

A torus source and its application for non-primary radiation evaluation.

Objective. Non-primary radiation doses to normal tissues from proton therapy may be associated with an increased risk of secondary malignancies, particularly in long-term survivors. Thus, a systematic method to evaluate if the dose level of non-primary radiation meets the IEC standard requirements is needed.Approach. Different from the traditional photon radiation therapy system, proton therapy systems are composed of several subsystems in a thick bunker. These subsystems are all possible sources of non-primary radiation threatening the patient. As a case study, 7 sources in the P-Cure synchrotron-based proton therapy system are modeled in Monte Carlo (MC) code: tandem injector, injection, synchrotron ring, extraction, beam transport line, scanning nozzle and concrete reflection/scattering. To accurately evaluate the synchrotron beam loss and non-primary dose, a new model called the torus source model is developed. Its parametric equations define the position and direction of the off-orbit particle bombardment on the torus pipe shell in the Cartesian coordinate system. Non-primary doses are finally calculated by several FLUKA simulations.Main results. The ratios of summarized non-primary doses from different sources to the planned dose of 2 Gy are all much smaller than the IEC requirements in both the 15-50 cm and 50-200 cm regions. Thus, the P-Cure synchrotron-based proton therapy system is clean and patient-friendly, and there is no need an inner shielding concrete between the accelerator and patient.Significance. Non-primary radiation dose level is a very important indicator to evaluate the quality of a PT system. This manuscript provides a feasible MC procedure for synchrotron-based proton therapy with new beam loss model. Which could help people figure out precisely whether this level complies with the IEC standard before the system put into clinical treatment. What' more, the torus source model could be widely used for bending magnets in gantries and synchrotrons to evaluate non-primary doses or other radiation doses.

Enthalpy and entropy synergistic regulation-based programmable DNA motifs for biosensing and information encryption.

Deoxyribonucleic acid (DNA) provides a collection of intelligent tools for the development of information cryptography and biosensors. However, most conventional DNA regulation strategies rely solely on enthalpy regulation, which suffers from unpredictable stimuli-responsive performance and unsatisfactory accuracy due to relatively large energy fluctuations. Here, we report an enthalpy and entropy synergistic regulation-based pH-responsive A+/C DNA motif for programmable biosensing and information encryption. In the DNA motif, the variation in loop length alters entropic contribution, and the number of A+/C bases regulates enthalpy, which is verified through thermodynamic characterizations and analyses. On the basis of this straightforward strategy, the performances, such as pKa, of the DNA motif can be precisely and predictably tuned. The DNA motifs are finally successfully applied for glucose biosensing and crypto-steganography systems, highlighting their potential in the field of biosensing and information encryption.

Bioinformatics analysis of ferroptosis in spinal cord injury.

Ferroptosis plays a key role in aggravating the progression of spinal cord injury (SCI), but the specific mechanism remains unknown. In this study, we constructed a rat model of T10 SCI using a modified Allen method. We identified 48, 44, and 27 ferroptosis genes that were differentially expressed at 1, 3, and 7 days after SCI induction. Compared with the sham group and other SCI subgroups, the subgroup at 1 day after SCI showed increased expression of the ferroptosis marker acyl-CoA synthetase long-chain family member 4 and the oxidative stress marker malondialdehyde in the injured spinal cord while glutathione in the injured spinal cord was lower. These findings with our bioinformatics results suggested that 1 day after SCI was the important period of ferroptosis progression. Bioinformatics analysis identified the following top ten hub ferroptosis genes in the subgroup at 1 day after SCI: STAT3, JUN, TLR4, ATF3, HMOX1, MAPK1, MAPK9, PTGS2, VEGFA, and RELA. Real-time polymerase chain reaction on rat spinal cord tissue confirmed that STAT3, JUN, TLR4, ATF3, HMOX1, PTGS2, and RELA mRNA levels were up-regulated and VEGFA, MAPK1 and MAPK9 mRNA levels were down-regulated. Ten potential compounds were predicted using the DSigDB database as potential drugs or molecules targeting ferroptosis to repair SCI. We also constructed a ferroptosis-related mRNA-miRNA-lncRNA network in SCI that included 66 lncRNAs, 10 miRNAs, and 12 genes. Our results help further the understanding of the mechanism underlying ferroptosis in SCI.

Molecular Visual Sensing, Boolean Logic Computing, and Data Security Using a Droplet-Based Superwetting Paradigm.

Inspired by information processing and logic operations of life, many artificial biochemical systems have been designed for applications in molecular information processing. However, encoding the binary synergism between matter, energy, and information in a superwetting system remains challenging. Herein, a superwetting paradigm was proposed for multifunctional applications including molecular visual sensing and data security on a superhydrophobic surface. A Triton X-100-encapsulated gelatin (TeG) hydrogel was prepared and selectively decomposed by trypsin, releasing the surfactant to decrease the surface tension of a droplet. Integrating the droplet with the superhydrophobic surface, the superwetting behavior was utilized for visual detection and information encoding. Interestingly, the proposed TeG hydrogel can function as an artificial gelneuron for molecular-level logic computing, where the combination of matters (superhydrophobic surface, trypsin, and leupeptin) acts as inputs to interact with energy (liquid surface tension and solid surface energy) and information (binary character), resulting in superwettability transitions (droplet surface tension, contact angle, rolling angle, and bounce) as outputs. Impressively, the TeG gelneuron can be further developed as molecular-level double cryptographic steganography to encode, encrypt, and hide specific information (including the maze escape route and content of the classical literature) due to its programmability, stimuli responsive ability, and droplet concealment. This study will encourage the development of advanced molecular paradigms and their applications, such as superwetting visual sensing, molecular computing, interaction, and data security.

Feeding Alginate-Coated Liquid Metal Nanodroplets to Silkworms for Highly Stretchable Silk Fibers.

In this study, we fed the larval of Bombyx mori silkworms with nanodroplets of liquid metal (LM) coated with microgels of marine polysaccharides to obtain stretchable silk. Alginate-coated liquid metal nanodroplets (LM@NaAlg) were prepared with significant chemical stability and biocompatibility. This study demonstrates how the fed LM@NaAlg acts on the as-spun silk fiber. We also conducted a series of characterizations and steered molecular dynamics simulations, which showed that the LM@NaAlg additions impede the conformation transition of silk fibroins from the random coil and α-helix to the ß-sheet by the formation of hydrogen bonds between LM@NaAlg and the silk fibroins, thus enhancing the elongation at the breakpoints in addition to the tensile properties. The intrinsically highly stretchable silk showed outstanding mechanical properties compared with regular silk due to its 814 MPa breaking strength and a breaking elongation of up to 70%-the highest reported performance so far. We expect that the proposed method can expand the fabrication of multi-functional silks.

Label-Free Resonance Rayleigh Scattering Amplification for Lipopolysaccharide Detection and Logical Circuit by CRISPR/Cas12a-Driven Guanine Nanowire Assisted Non-Cross-Linking Hybridization Chain Reaction.

Although the CRISPR/Cas system has pioneered a new generation of analytical techniques, there remain many challenges in developing a label-free, accurate, and reliable CRISPR/Cas-based assay for reporting the levels of low abundance biomolecules in complex biological samples. Here, we reported a novel CRISPR-derived resonance Rayleigh scattering (RRS) amplification strategy and logical circuit based on a guanine nanowire (G-wire) assisted non-cross-linking hybridization chain reaction (GWancHCR) for label-free detection of lipopolysaccharide (LPS). In the presence of a target, the protospacer-adjacent motif-inserted aptamer is rationally designed to specifically combine with LPS rather than Cas12a, suppressing the trans-cleavage activity of CRISPR/Cas12a and retaining the reporter probes to trigger non-cross-linking aggregation. Owing to the automatic hybridization chain reaction (HCR), in the presence of Mg2+, the released G-quadruplex sequence aggregated to assemble the G-wire superstructure through non-cross-linking. As a result, a dramatically amplified RRS intensity is observed, allowing for reporting LPS levels in a low detection limit of 0.17 pg/mL and a wide linear range among 1.0-100.0 ng/mL. Moreover, this reaction event is capable of programming to perform classical Boolean logic tree analysis, including basic logic computing and complex integrated logic circuits. This study comprehensively analyzed with respect to information flow, matter (molecular events), and energy (RRS), revealing the potential promise in designing of molecular-level "Internet of Things", intelligent computing, and sensing systems.

pH-Responsive DNA Motif: From Rational Design to Analytical Applications.

pH-responsive DNA motifs have attracted substantial attention attributed to their high designability and versatility of DNA chemistry. Such DNA motifs typically exploit DNA secondary structures that exhibit pH response properties because of the presence of specific protonation sites. In this review, we briefly summarized second structure-based pH-responsive DNA motifs, including triplex DNA, i-motif, and A+-C mismatch base pair-based DNA devices. Finally, the challenges and prospects of pH-responsive DNA motifs are also discussed.

Mechanically Stretched Mesenchymal Stem Cells Can Reduce the Effects of LPS-Induced Injury on the Pulmonary Microvascular Endothelium Barrier.

Mesenchymal stem cells (MSCs) may improve the treatment of acute respiratory distress syndrome (ARDS). However, few studies have investigated the effects of mechanically stretched -MSCs (MS-MSCs) in in vitro models of ARDS. The aim of this study was to evaluate the potential therapeutic effects of MS-MSCs on pulmonary microvascular endothelium barrier injuries induced by LPS. We introduced a cocultured model of pulmonary microvascular endothelial cell (EC) and MSC medium obtained from MSCs with or without mechanical stretch. We found that Wright-Giemsa staining revealed that MSC morphology changed significantly and cell plasma shrank separately after mechanical stretch. Cell proliferation of the MS-MSC groups was much lower than the untreated MSC group; expression of cell surface markers did not change significantly. Compared to the medium from untreated MSCs, inflammatory factors elevated statistically in the medium from MS-MSCs. Moreover, the paracellular permeability of endothelial cells treated with LPS was restored with a medium from MS-MSCs, while LPS-induced EC apoptosis decreased. In addition, protective effects on the remodeling of intercellular junctions were observed when compared to LPS-treated endothelial cells. These data demonstrated that the MS-MSC groups had potential therapeutic effects on the LPS-treated ECs; these results might be useful in the treatment of ARDS.

The Anti-Allergic Rhinitis Effect of Traditional Chinese Medicine of Shenqi by Regulating Mast Cell Degranulation and Th1/Th2 Cytokine Balance.

Shenqi is a traditional Chinese polyherbal medicine has been widely used for the treatment of allergic rhinitis (AR). The aim of this study was to investigate the anti-allergic rhinitis activity of Shenqi and explore its underlying molecular mechanism. Ovalbumin (OVA)-induced allergic rhinitis rat model was used to evaluate the anti-allergic rhinitis effect of Shenqi. The effect of Shenqi on IgE-mediated degranulation was measured using rat basophilic leukemia (RBL-2H3) cells. Primary spleen lymphocytes were isolated to investigate the anti-allergic mechanism of Shenqi by detecting the expression of transcription factors via Western blot and the level of cytokines (IL-4 and IFN-γ) via ELISA. In OVA-induced AR rat models, Shenqi relieved the allergic rhinitis symptoms, inhibited the histopathological changes of nasal mucosa, and reduced the levels of IL-4 and IgE. The results from the in vitro study certified that Shenqi inhibited mast cell degranulation. Furthermore, the results of GATA3, T-bet, p-STAT6, and SOCS1 expression and production of IFN-γ and IL-4 demonstrated that Shenqi balanced the ratio of Th1/Th2 (IFN-γ/IL-4) in OVA-stimulated spleen lymphocytes. In conclusion, these results suggest that Shenqi exhibits an obvious anti-allergic effect by suppressing the mast cell-mediated allergic response and by improving the imbalance of Th1/Th2 ratio in allergic rhinitis.

[Recent development of non-steroidal anti-inflammatory drugs on the neuro-inflammation of Alzheimer's disease].

Neuropathological, clinical epidemiology and animal models studies provide clear evidence for the activation of neuroinflammation in Alzheimer's disease (AD), and long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) is linked with reduced risk to develop the disease. But the clinical trials got a negative outcome with traditional NSAIDs treating AD. The therapeutic effects of NSAIDs on Alzheimer's disease are still not clear based on the present research. Profound study for anti-inflammatory mechanisms and standardized clinical trials are needed. As cause and effect relationships between neuroinflammation and AD are being worked out, the challenge is how to realize the effect of traditional NSAIDs on treating AD.

Pinocembrin protects human brain microvascular endothelial cells against fibrillar amyloid-ß(1-40) injury by suppressing the MAPK/NF-κB inflammatory pathways.

Cerebrovascular accumulation of amyloid-ß (Aß) peptides in Alzheimer's disease (AD) may contribute to disease progression through Aß-induced microvascular endothelial pathogenesis. Pinocembrin has been shown to have therapeutic effects in AD models. These effects correlate with preservation of microvascular function, but the effect on endothelial cells under Aß-damaged conditions is unclear. The present study focuses on the in vitro protective effect of pinocembrin on fibrillar Aß(1-40) (fAß(1-40)) injured human brain microvascular endothelial cells (hBMECs) and explores potential mechanisms. The results demonstrate that fAß(1-40)-induced cytotoxicity in hBMECs can be rescued by pinocembrin treatment. Pinocembrin increases cell viability, reduces the release of LDH, and relieves nuclear condensation. The mechanisms of this reversal from Aß may be associated with the inhibition of inflammatory response, involving inhibition of MAPK activation, downregulation of phosphor-IKK level, relief of IκBα degradation, blockage of NF-κB p65 nuclear translocation, and reduction of the release of proinflammatory cytokines. Pinocembrin does not show obvious effects on regulating the redox imbalance after exposure to fAß(1-40). Together, the suppression of MAPK and the NF-κB signaling pathways play a significant role in the anti-inflammation of pinocembrin in hBMECs subjected to fAß(1-40). This may serve as a therapeutic agent for BMEC protection in Alzheimer's-related deficits.

Pinocembrin improves cognition and protects the neurovascular unit in Alzheimer related deficits.

Amyloid-ß (Aß) peptides accumulate in the brain and initiate a cascade of pathologic events in Alzheimer's disease. The receptor for advanced glycation end products (RAGE) has been implicated to mediate Aß-induced perturbations in the neurovascular unit (NVU). We demonstrated that pinocembrin exhibits neuroprotection through inhibition of the Aß and/or RAGE pathway, but the therapeutic role and mechanism involved are not ascertained. Here, we report that a 3-month treatment with pinocembrin prevents the cognition decline in APP/PS1 transgenic mice without altering Aß burden and oxidative stress. Instead, pinocembrin is effective in conferring neurovascular protection through maintenance of neuropil ultrastructure, reduction of glial activation and levels of inflammatory mediators, preservation of microvascular function, improving the cholinergic system by conserving the ERK-CREB-BDNF pathway, and modulation of RAGE-mediated transduction. Furthermore, in an in vitro model, pinocembrin provides the NVU protection against fibrillar Aß1₋42, accompanied by regulation of neurovascular RAGE pathways. Our findings indicate that pinocembrin improves cognition, at least in part, attributable to the NVU protection, and highlights pinocembrin as a potential therapeutic strategy for the prevention and/or treatment of Alzheimer's disease.

[Prognostic value of N terminal pro B type natriuretic peptide in critically ill patients].

OBJECTIVE: To investigate whether plasma N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) as measured at admission to intensive care unit (ICU) is an independent predictor of mortality in critically ill patients. METHODS: A prospective observational study of patients in ICU was conducted . One hundred and twenty patients aged>18 years were included during a 6 month period. Among them 88 patients were enrolled for the study. Plasma NT-pro-BNP samples were obtained at admission to ICU. The acute physiology and chronic health evaluation II(APACHEII) score was calculated within 24 hours after admission based on the worst values up to that point. The final evaluation was 28 day mortality. RESULTS: Thirty five patients died within 28 days of ICU admission, the mortality was 39.8%. In 88 patients , the mean plasma NT-pro-BNP levels (ng/L) were 1 221.7 (78.75 500.0), and that in survivor group was significantly lower than non survivor group [781.8 (78.75 066.6) vs. 2 774.5 ( 166.85 500.0 ), P <0.01]. The mean NT-pro-BNP level (ng/L) in male patients was higher than that in females [1 585.5 (103.75 100.0) vs. 794.5 (78.75 500.0), P <0.05]. There was correlation between gender and NT-pro-BNP levels ( r =-0.224, P <0.05). Patients admitted to the ICU because of a severe infection had higher levels of NT-pro-BNP (ng/L) compared with the rest of the cohorts [3 416.1 (103.7 5 100.0) vs. 883.4 (78.75 500.0), P <0.01]. There was correlation between severe infection at admission to ICU and NT-pro-BNP levels ( r =0.285, P <0.01). Areas under the receiver operating characteristic curves (ROC curves) of NT-pro-BNP and APACHEII score were 0.734[95% confidence interval (95% CI ) 0.6280.840] and 0.747 (95% CI 0.6370.858), respectively. Logistic regression analysis showed that the NT-pro-BNP level> 1 418 ng/L and the APACHEII score were independently associated with 28 day mortality [odds ratio ( OR ) 5.235, 95% CI 1.81915.071; OR 1.105, 95% CI 1.81915.071]. With 1 418 ng/L of NT-pro-BNP as the cutoff value, survival rate was significantly lower in the patients with higher NT-pro-BNP level as compared with those with lower values at admission (χ²=16.9, P <0.01). CONCLUSION: The ICU NT-pro-BNP level higher than 1 418 ng/L and APACHEII score at admission are independent prognosis markers of early mortality. NT-pro-BNP might serve as a potent early diagnostic and prognostic marker in critically ill patients.

[Effects of cholinergic anti-inflammatory pathway on ventilator-induced lung injury in rats].

OBJECTIVE: To investigate the effects of cholinergic anti-inflammatory pathway on ventilator-induced lung injury (VILI) in rats. METHODS: Thirty-six healthy Sprague-Dawley (SD) rats were randomly divided into three groups: control group, in which rats did not receive ventilation; high-tidal volume (HVT) ventilation group; nicotine treatment (HVT+nicotine) group, in which rats received intraperitoneal injection of nicotine (2 mg/kg) 10 minutes before HVT ventilation; equal amount of normal saline was given to rats in other two groups. A rat model of VILI was reproduced by volume-controlled mechanical ventilation with HVT. Hemodynamic parameters were measured throughout the study period. Arterial blood gases were measured every 1 hour. After maintaining ventilation for 2 hours, rats were sacrificed and lung tissue specimens were harvested. Lung wet-dry weight ratio (W/D) and myeloperoxidase (MPO) activity were measured. Interleukin-8 (IL-8) level in bronchoalveolar lavage fluid (BALF) and intercellular adhesion molecule-1 (ICAM-1) level in lung tissue homogenate were measured by enzyme-linked immunosorbent assay (ELISA), respectively. After hematoxylin and eosin (HE) staining, pathological examination of lung tissue was performed, and diffuse alveolar damage (DAD) score was estimated. RESULTS: Mean pH of arterial blood in HVT group and HVT+nicotine group tended to be higher than the baseline value during the ventilation. Mean partial pressure of oxygen in arterial blood (PaO2), mean partial pressure of carbon dioxide in arterial blood (PaCO2), and mean arterial pressure (MAP) in HVT group and HVT+nicotine group were lower than baseline value during the ventilation. Mean PaO2 (mm Hg, 1 mm Hg=0.133 kPa) in HVT+nicotine group was significantly higher than that in HVT group after 2 hours of ventilation (85+/-4 vs. 76+/-3, P<0.05). Mean W/D ratio and mean MPO activity in HVT group were significantly higher than those in control group [W/D ratio: 5.66+/-0.33 vs. 4.53+/-0.21, P<0.01; MPO (U/g): 1.73+/-0.50 vs. 0.89+/-0.17, P<0.05]. Mean W/D ratio (5.02+/-0.37) and mean MPO activity (1.11+/-0.33) in HVT+nicotine group were significantly lower than those in HVT group (both P<0.05). Compared with control group, DAD scores in HVT group and HVT+nicotine group (10.40+/-1.85, 7.90+/-1.67 vs. 1.60+/-1.20), IL-8 concentration (ng/L: 1 625.3+/-271.7, 965.5+/-310.5 vs. 428.5+/-120.6) and ICAM-1 concentration (microg/L: 589.4+/-87.5, 452.5+/-89.3 vs. 247.5+/-73.7) were significantly higher (all P<0.01). But DAD score, IL-8 concentration, ICAM-1 concentration in HVT+nicotine group were significantly lower than those in HVT group (P<0.05 or P<0.01). CONCLUSION: Activation of cholinergic anti-inflammatory pathway can protect the lung against VILI by suppressing IL-8 and ICAM-1 expression, inhibiting neutrophil aggregation and infiltration.

[Mitochondrial DNA D-loop variation types in Tibet mini-pigs in association with the blood parameters].

OBJECTIVE: To analyze the mitochondrial DNA (mtDNA) D-loop region sequence variation in Tibet Mini-Pigs in relation to the blood parameters and provide the molecular genetic basis for developing new species of laboratory animals. METHODS: The genomic DNA was extracted from the whole blood samples of 59 Tibet mini-pigs to amplifying the mtDNA D-loop for sequence analysis. Nine physiological and nine biochemical blood parameters of Tibet mini-pigs were measured . RESULTS: Based on the variation of the tandem repeat motif, the mtDNA D-loop region of Tibet mini-pigs was classified into two types, namely type A and B with the percentage of 57.6% and 42.4%, respectively, roughly matching the 3 transform sites (305, 500, 691) at the 5' end. In the 18 blood parameters, only red blood cell count showed significant differences between types A and (P<0.01). CONCLUSION: Based on the sequence variation of the mtDNA D-loop region, Tibet mini-pigs can be divided into two types that show a significant difference in red blood cell count.