Background: Despite the fact that an increasing number of studies have focused on developing therapies for acute lung injury, managing acute respiratory distress syndrome (ARDS) remains a challenge in intensive care medicine.Whether the pathology of animal models with acute lung injury in prior studies differed from clinical symptoms of ARDS, resulting in questionable management for human ARDS. To evaluate precisely the therapeutic effect of trans‑ planted stem cells or medications on acute lung injury, we developed an animal model of severe ARDS with lower lung function, capable of keeping the experimental animals survive with consistent reproducibility. Establishing this animal model could help develop the treatment of ARDS with higher efficiency. Results: In this approach, we intratracheally delivered bleomycin (BLM, 5 mg/rat) into rats’ left trachea via a needle connected with polyethylene tube, and simultaneously rotated the rats to the left side by 60 degrees. Within sevendays after the injury, we found that arterial blood oxygen saturation ­(SpO2 ) significantly decreased to 83.7%, partial pressure of arterial oxygen ­(PaO2 ) markedly reduced to 65.3 mmHg, partial pressure of arterial carbon dioxide ­(PaCO2 )amplified to 49.2 mmHg, and the respiratory rate increased over time. Morphologically, the surface of the left lung appeared uneven on Day 1, the alveoli of the left lung disappeared on Day 2, and the left lung shrank on Day 7. A his‑ tological examination revealed that considerable cell infiltration began on Day 1 and lasted until Day 7, with a larger area of cell infiltration. Serum levels of IL-5, IL-6, IFN-γ, MCP-1, MIP-2, G-CSF, and TNF-α substantially rose on Day 7. Conclusions This modified approach for BLM-induced lung injury provided a severe, stable, and one-sided (left-lobe) ARDS animal model with consistent reproducibility. The physiological symptoms observed in this severe ARDS animal model are entirely consistent with the characteristics of clinical ARDS. The establishment of this ARDS animal model could help develop treatment for ARDS.

Background: Despite the fact that an increasing number of studies have focused on developing therapies for acute lung injury, managing acute respiratory distress syndrome (ARDS) remains a challenge in intensive care medicine.Whether the pathology of animal models with acute lung injury in prior studies differed from clinical symptoms of ARDS, resulting in questionable management for human ARDS. To evaluate precisely the therapeutic effect of trans‑ planted stem cells or medications on acute lung injury, we developed an animal model of severe ARDS with lower lung function, capable of keeping the experimental animals survive with consistent reproducibility. Establishing this animal model could help develop the treatment of ARDS with higher efficiency. Results: In this approach, we intratracheally delivered bleomycin (BLM, 5 mg/rat) into rats’ left trachea via a needle connected with polyethylene tube, and simultaneously rotated the rats to the left side by 60 degrees. Within sevendays after the injury, we found that arterial blood oxygen saturation ­(SpO2 ) significantly decreased to 83.7%, partial pressure of arterial oxygen ­(PaO2 ) markedly reduced to 65.3 mmHg, partial pressure of arterial carbon dioxide ­(PaCO2 )amplified to 49.2 mmHg, and the respiratory rate increased over time. Morphologically, the surface of the left lung appeared uneven on Day 1, the alveoli of the left lung disappeared on Day 2, and the left lung shrank on Day 7. A his‑ tological examination revealed that considerable cell infiltration began on Day 1 and lasted until Day 7, with a larger area of cell infiltration. Serum levels of IL-5, IL-6, IFN-γ, MCP-1, MIP-2, G-CSF, and TNF-α substantially rose on Day 7. Conclusions This modified approach for BLM-induced lung injury provided a severe, stable, and one-sided (left-lobe) ARDS animal model with consistent reproducibility. The physiological symptoms observed in this severe ARDS animal model are entirely consistent with the characteristics of clinical ARDS. The establishment of this ARDS animal model could help develop treatment for ARDS.

Background: Despite the fact that an increasing number of studies have focused on developing therapies for acute lung injury, managing acute respiratory distress syndrome (ARDS) remains a challenge in intensive care medicine.Whether the pathology of animal models with acute lung injury in prior studies differed from clinical symptoms of ARDS, resulting in questionable management for human ARDS. To evaluate precisely the therapeutic effect of trans‑ planted stem cells or medications on acute lung injury, we developed an animal model of severe ARDS with lower lung function, capable of keeping the experimental animals survive with consistent reproducibility. Establishing this animal model could help develop the treatment of ARDS with higher efficiency. Results: In this approach, we intratracheally delivered bleomycin (BLM, 5 mg/rat) into rats’ left trachea via a needle connected with polyethylene tube, and simultaneously rotated the rats to the left side by 60 degrees. Within sevendays after the injury, we found that arterial blood oxygen saturation ­(SpO2 ) significantly decreased to 83.7%, partial pressure of arterial oxygen ­(PaO2 ) markedly reduced to 65.3 mmHg, partial pressure of arterial carbon dioxide ­(PaCO2 )amplified to 49.2 mmHg, and the respiratory rate increased over time. Morphologically, the surface of the left lung appeared uneven on Day 1, the alveoli of the left lung disappeared on Day 2, and the left lung shrank on Day 7. A his‑ tological examination revealed that considerable cell infiltration began on Day 1 and lasted until Day 7, with a larger area of cell infiltration. Serum levels of IL-5, IL-6, IFN-γ, MCP-1, MIP-2, G-CSF, and TNF-α substantially rose on Day 7. Conclusions This modified approach for BLM-induced lung injury provided a severe, stable, and one-sided (left-lobe) ARDS animal model with consistent reproducibility. The physiological symptoms observed in this severe ARDS animal model are entirely consistent with the characteristics of clinical ARDS. The establishment of this ARDS animal model could help develop treatment for ARDS.

Background: Despite the fact that an increasing number of studies have focused on developing therapies for acute lung injury, managing acute respiratory distress syndrome (ARDS) remains a challenge in intensive care medicine.Whether the pathology of animal models with acute lung injury in prior studies differed from clinical symptoms of ARDS, resulting in questionable management for human ARDS. To evaluate precisely the therapeutic effect of trans‑ planted stem cells or medications on acute lung injury, we developed an animal model of severe ARDS with lower lung function, capable of keeping the experimental animals survive with consistent reproducibility. Establishing this animal model could help develop the treatment of ARDS with higher efficiency. Results: In this approach, we intratracheally delivered bleomycin (BLM, 5 mg/rat) into rats’ left trachea via a needle connected with polyethylene tube, and simultaneously rotated the rats to the left side by 60 degrees. Within sevendays after the injury, we found that arterial blood oxygen saturation ­(SpO2 ) significantly decreased to 83.7%, partial pressure of arterial oxygen ­(PaO2 ) markedly reduced to 65.3 mmHg, partial pressure of arterial carbon dioxide ­(PaCO2 )amplified to 49.2 mmHg, and the respiratory rate increased over time. Morphologically, the surface of the left lung appeared uneven on Day 1, the alveoli of the left lung disappeared on Day 2, and the left lung shrank on Day 7. A his‑ tological examination revealed that considerable cell infiltration began on Day 1 and lasted until Day 7, with a larger area of cell infiltration. Serum levels of IL-5, IL-6, IFN-γ, MCP-1, MIP-2, G-CSF, and TNF-α substantially rose on Day 7. Conclusions This modified approach for BLM-induced lung injury provided a severe, stable, and one-sided (left-lobe) ARDS animal model with consistent reproducibility. The physiological symptoms observed in this severe ARDS animal model are entirely consistent with the characteristics of clinical ARDS. The establishment of this ARDS animal model could help develop treatment for ARDS.

Background: Despite the fact that an increasing number of studies have focused on developing therapies for acute lung injury, managing acute respiratory distress syndrome (ARDS) remains a challenge in intensive care medicine.Whether the pathology of animal models with acute lung injury in prior studies differed from clinical symptoms of ARDS, resulting in questionable management for human ARDS. To evaluate precisely the therapeutic effect of trans‑ planted stem cells or medications on acute lung injury, we developed an animal model of severe ARDS with lower lung function, capable of keeping the experimental animals survive with consistent reproducibility. Establishing this animal model could help develop the treatment of ARDS with higher efficiency. Results: In this approach, we intratracheally delivered bleomycin (BLM, 5 mg/rat) into rats’ left trachea via a needle connected with polyethylene tube, and simultaneously rotated the rats to the left side by 60 degrees. Within sevendays after the injury, we found that arterial blood oxygen saturation ­(SpO2 ) significantly decreased to 83.7%, partial pressure of arterial oxygen ­(PaO2 ) markedly reduced to 65.3 mmHg, partial pressure of arterial carbon dioxide ­(PaCO2 )amplified to 49.2 mmHg, and the respiratory rate increased over time. Morphologically, the surface of the left lung appeared uneven on Day 1, the alveoli of the left lung disappeared on Day 2, and the left lung shrank on Day 7. A his‑ tological examination revealed that considerable cell infiltration began on Day 1 and lasted until Day 7, with a larger area of cell infiltration. Serum levels of IL-5, IL-6, IFN-γ, MCP-1, MIP-2, G-CSF, and TNF-α substantially rose on Day 7. Conclusions This modified approach for BLM-induced lung injury provided a severe, stable, and one-sided (left-lobe) ARDS animal model with consistent reproducibility. The physiological symptoms observed in this severe ARDS animal model are entirely consistent with the characteristics of clinical ARDS. The establishment of this ARDS animal model could help develop treatment for ARDS.

Objective: To investigate the characteristics of malignant tumor incidence and mortality in cancer registration areas of Sichuan Province in 2021. Methods: Cancer registration data from 142 registries in Sichuan Province in 2021 were collected via the China Cancer Registry Platform. Crude incidence and crude mortality were calculated. The Chinese population-standardized incidence and world population-standardized incidence were standardized using the age structure of the standard population from the Fifth National Population Census in 2000 and Segi's world standard population. Descriptive analyses examined the distribution of rates by genders, urban/rural areas, and ages, and the ranking of leading cancer sites. Results: In 2021, there were 248 600 new malignant tumor cases reported in Sichuan Province, with a crude incidence of 296.37/100 000. The Chinese population-standardized incidence and world population-standardized incidence were 164.67/100 000 and 160.47/100 000, respectively. There were 158 673 malignant tumor deaths, with a crude mortality of 189.16/100 000. The Chinese population-standardized mortality and world population-standardized mortality were 92.47/100 000 and 92.00/100 000, respectively. The Chinese population-standardized incidence and mortality in males were higher than in females (179.56/100 000 vs. 151.62/100 000, 125.09/100 000 vs. 60.35/100 000). The Chinese population-standardized incidence and mortality in urban areas were higher than in rural areas (175.74/100 000 vs. 157.54/100 000, 93.63/100 000 vs. 91.82/100 000). Both the crude incidence and crude mortality increased with age. The top ten malignant tumors by crude incidence were lung cancer, colorectal cancer, liver cancer, breast cancer, esophageal cancer, gastric cancer, cervical cancer, prostate cancer, thyroid cancer, and corpus uteri cancer, accounting for 76.33% of all new cases. The top ten by crude mortality were lung cancer, liver cancer, esophageal cancer, colorectal cancer, gastric cancer, breast cancer, pancreatic cancer, cervical cancer, prostate cancer, and brain tumors, accounting for 82.39% of all cancer deaths. Conclusions In registration areas of Sichuan Province, the incidence and mortality of malignant tumors are relatively low. Key populations such as males, urban residents, and the elderly require focused prevention and control efforts. Comprehensive measures should be prioritized for malignant tumors including lung cancer, liver cancer, esophageal cancer, gastric cancer, colorectal cancer, and breast cancer.

The present study aimed to explore whether hydrogen sulfide (H₂S) improved hypoxic pulmonary hypertension (HPH) in rats by inhibiting aerobic glycolysis-pyroptosis. Male Sprague-Dawley (SD) rats were randomly divided into normal group, normal+NaHS group, hypoxia group, and hypoxia+NaHS group, with 6 rats in each group. The control group rats were placed in a normoxic (21% O₂) environment and received daily intraperitoneal injections of an equal volume of normal saline. The normal+NaHS group rats were placed in a normoxic environment and intraperitoneally injected with 14 μmol/kg NaHS daily. The hypoxia group rats were placed in a hypoxia chamber, and the oxygen controller inside the chamber maintained the oxygen concentration at 9% to 10% by controlling the N₂ flow rate. An equal volume of normal saline was injected intraperitoneally every day. The hypoxia+NaHS group rats were also placed in an hypoxia chamber and intraperitoneally injected with 14 μmol/kg NaHS daily. After the completion of the four-week modeling, the mean pulmonary artery pressure (mPAP) of each group was measured using right heart catheterization technique, and the right ventricular hypertrophy index (RVHI) was weighed and calculated. HE staining was used to observe pathological changes in lung tissue, Masson staining was used to observe fibrosis of lung tissue, and Western blot was used to detect protein expression levels of hexokinase 2 (HK2), pyruvate dehydrogenase (PDH), pyruvate kinase isozyme type M2 (PKM2), nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), GSDMD-N-terminal domain (GSDMD-N), Caspase-1, interleukin-1β (IL-1β) and IL-18 in lung tissue. ELISA was used to detect contents of IL-1β and IL-18 in lung tissue. The results showed that, compared with the normal control group, there were no significant changes in all indexes in the normal+NaHS group, while the hypoxia group exhibited significantly increased mPAP and RVHI, thickened pulmonary vascular wall, narrowed lumen, increased collagen fibers, up-regulated expression levels of aerobic glycolysis-related proteins (HK2 and PKM2), up-regulated expression levels of pyroptosis-related proteins (NLRP3, GSDMD-N, Caspase-1, IL-1β, and IL-18), and increased contents of IL-1β and IL-18. These changes of the above indexes in the hypoxia group were significantly reversed by NaHS. These results suggest that H₂S can improve rat HPH by inhibiting aerobic glycolysis-pyroptosis.
Animals ; Rats, Sprague-Dawley ; Male ; Hypertension, Pulmonary/metabolism* ; Glycolysis/drug effects* ; Hydrogen Sulfide/therapeutic use* ; Hypoxia/complications* ; Rats ; Pyroptosis/drug effects*

The aim of this study was to investigate the contribution of lung zinc ions to pathogenesis of lung ischemia/reperfusion (I/R) injury in rats. Male Sprague Dawley (SD) rats were randomly divided into control group, lung I/R group (I/R group), lung I/R + low-dose zinc chloride group (LZnCl₂+I/R group), lung I/R + high-dose ZnCl₂ group (HZnCl₂+I/R group), lung I/R + medium-dose ZnCl₂ group (MZnCl₂+I/R group) and TPEN+MZnCl₂+I/R group (n = 8 in each group). Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure the concentration of zinc ions in lung tissue. The degree of lung tissue injury was analyzed by observing HE staining, alveolar damage index, lung wet/dry weight ratio and lung tissue gross changes. TUNEL staining was used to detect cellular apoptosis in lung tissue. Western blot and RT-qPCR were used to determine the protein expression levels of caspase-3 and ZIP8, as well as the mRNA expression levels of zinc transporters (ZIP, ZNT) in lung tissue. The mitochondrial membrane potential (MMP) of lung tissue was detected by JC-1 MMP detection kit. The results showed that, compared with the control group, the lung tissue damage, lung wet/dry weight ratio and alveolar damage index were significantly increased in the I/R group. And in the lung tissue, the concentration of Zn²⁺ was markedly decreased, while the cleaved caspase-3/caspase-3 ratio and apoptotic levels were significantly increased. The expression levels of ZIP8 mRNA and protein were down-regulated significantly, while the mRNA expression of other zinc transporters remained unchanged. There was also a significant decrease in MMP. Compared with the I/R group, both MZnCl₂+I/R group and HZnCl₂+I/R group exhibited significantly reduced lung tissue injury, lung wet/dry weight ratio and alveolar damage index, increased Zn²⁺ concentration, decreased ratio of cleaved caspase-3/caspase-3 and apoptosis, and up-regulated expression levels of ZIP8 mRNA and protein. In addition, the MMP was significantly increased in the lung tissue. Zn²⁺ chelating agent TPEN reversed the above-mentioned protective effects of medium-dose ZnCl₂ on the lung tissue in the I/R group. The aforementioned results suggest that exogenous administration of ZnCl₂ can improve lung I/R injury in rats.
Animals ; Reperfusion Injury/pathology* ; Male ; Rats, Sprague-Dawley ; Rats ; Chlorides/administration & dosage* ; Lung/pathology* ; Zinc Compounds/administration & dosage* ; Apoptosis/drug effects* ; Caspase 3/metabolism* ; Cation Transport Proteins/metabolism*

Objective:To prepare the chitin/hyaluronic acid/collagen hydrogel loaded with mouse adipose-derived stem cells and to explore its effects on wound healing of full-thickness skin defects in rats.Methods:The research was an experimental research. Chitin nanofibers were prepared by acid hydrolysis and alkaline extraction method, and then mixed with hyaluronic acid and collagen to prepare chitin/hyaluronic acid/collagen hydrogels (hereinafter referred to as hydrogels). Besides, the hydrogels loaded with mouse adipose-derived stem cells were prepared. Thirty male 12-week-old guinea pigs were divided into negative control group, positive control group, and hydrogel group according to the random number table, with 10 guinea pigs in each group. Ethanol, 4-aminobenzoic acid ethyl ester, or the aforementioned prepared hydrogels without cells were topically applied on both sides of back of guinea pigs respectively for induced contact and stimulated contact, and skin edema and erythema formation were observed at 24 and 48 h after stimulated contact. Adipose-derived stem cells from mice were divided into normal control group cultured routinely and hydrogel group cultured with the aforementioned prepared hydrogels without cells. After 3 d of culture, protein expressions of platelet-derived growth factor-D (PDGF-D), insulin-like growth factor-Ⅰ (IGF-Ⅰ), and transforming growth factor β 1 (TGF-β 1) were detected by Western blotting ( n=3). Eight male 8-week-old Sprague-Dawley rats were taken and a circular full-thickness skin defect wound was created on each side of the back. The wounds were divided into blank control group without any treatment and hydrogel group with the aforementioned prepared hydrogels loaded with adipose-derived stem cells applied. Wound healing was observed at 0 (immediately), 2, 4, 8, and 10 d after injury, and the wound healing rate was calculated at 2, 4, 8, and 10 d after injury. Wound tissue samples at 10 d after injury were collected, the new tissue formation was observed by hematoxylin-eosin staining; the concentrations of interleukin-1α (IL-1α), IL-6, IL-4, and IL-10 were detected by enzyme-linked immunosorbent assay method; the expressions of CD16 and CD206 positive cells were observed by immunohistochemical staining and the percentages of positive cells were calculated. The sample numbers in animal experiment were all 8. Results:At 24 h after stimulated contact, no skin edema was observed in the three groups of guinea pigs, and only mild skin erythema was observed in 7 guinea pigs in positive control group. At 48 h after stimulated contact, skin erythema was observed in 8 guinea pigs and skin edema was observed in 4 guinea pigs in positive control group, while no obvious skin erythema or edema was observed in guinea pigs in the other two groups. After 3 d of culture, the protein expression levels of PDGF-D, IGF-I, and TGF-β 1 in adipose-derived stem cells in hydrogel group were significantly higher than those in normal control group (with t values of 12.91, 11.83, and 7.92, respectively, P<0.05). From 0 to 10 d after injury, the wound areas in both groups gradually decreased, and the wounds in hydrogel group were almost completely healed at 10 d after injury. At 4, 8, and 10 d after injury, the wound healing rates in hydrogel group were (38±4)%, (54±5)%, and (69±6)%, respectively, which were significantly higher than (21±6)%, (29±7)%, and (31±7)% in blank control group (with t values of 3.82, 3.97, and 4.05, respectively, Pvalues all <0.05). At 10 d after injury, compared with those in blank control group, the epidermis in wound in hydrogel group was more intact, and there were increases in hair follicles, blood vessels, and other skin appendages. At 10 d after injury, the concentrations of IL-1α and IL-6 in wound tissue in hydrogel group were significantly lower than those in blank control group (with tvalues of 8.21 and 7.99, respectively, P<0.05), while the concentrations of IL-4 and IL-10 were significantly higher than those in blank control group (with tvalues of 6.57 and 9.03, respectively, P<0.05). The percentage of CD16 positive cells in wound tissue in hydrogel group was significantly lower than that in blank control group ( t=8.02, P<0.05), while the percentage of CD206 positive cells was significantly higher than that in blank control group ( t=7.21, P<0.05). Conclusions:The hydrogel loaded with mouse adipose-derived stem cells is non-allergenic, can promote the secretion of growth factors in adipose-derived stem cells, promote the polarization of macrophages to M2 phenotype in wound tissue in rats with full-thickness skin defects, and alleviate inflammatory reaction, thereby promoting wound healing.

Objective To carry out rigid-body inverse dynamics modelling and analysis of a self-designed 6RSS parallel bio-inspired masticatory robot.Methods Firstly,the functions of kinematic variables including translational/rotational velocities and accelerations were derived for rigid-body inverse dynamics modelling.Secondly,the rigid-body inverse dynamics model was established with the Newton-Euler's law.Finally,the chewing motion trajectories of the oral health volunteers were tracked and numerical calculations were carried out in the case where the robot was subjected to a chewing reaction force.Results Numerical calculations showed that the driving torque and the constraint force of the robot peaked when the chewing reaction force was at its maximum.Conclusion The external force has a large impact on the inverse dynamics of the robot,and theoretical references are provided for the motion control and optimal design of the robot.[Chinese Medical Equipment Journal,2024,45(3):16-22]