[Objective] To extract hemoglobin (Hb) from red blood cells using osmotic pressure swelling method, expected to achieve a hemoglobin dissolution rate of ≥80% and a cell membrane integrity rate of ≥70%. [Methods] Human umbilical cord blood red blood cells were used as raw materials and phosphate buffer solution was used as the swelling solution for red blood cells. A three factor three-level orthogonal experiment (n=3) was conducted to determine the optimal matching conditions for selecting the osmolality molar concentration of phosphate buffer solution, pH value of hypotonic phosphate buffer solution and volume ratio of hypotonic phosphate buffer solution to washed red blood cells. Red blood cell swelling solution samples (n=6) were prepared by the optimal matching conditions and the original process conditions. The hemoglobin dissolution rate and cell membrane integrity rate were checked. In the expanded comparative experiment, red blood cell swelling solution samples (n=6) were prepared by the optimal matching conditions and the original process conditions, which was filtered by ultrafiltration membranes. The filtration time and hemoglobin yield were checked. [Results] The optimal matching conditions for preparing red blood cell swelling solution were obtained through orthogonal experiment as follows: osmotic pressure molar concentration was 30 mOsmol/Kg, pH was 7.8, and phosphate buffer to red blood cell volume ratio was 6∶1. On the basis of the above conditions, the red blood cell swelling solution sample was compared with the original process sample: the hemoglobin dissolution rate was (82.4±1.8)% vs (78.6±3.0)% (P<0.05), and the cell membrane integrity rate was (65.8±4.0)% vs (28.7±2.3)% (P<0.05). In the expanded comparative experiment, the optimal matching conditions were compared with the original process conditions: filtration time(s) (327±9) vs (434±13) (P<0.05), and hemoglobin yield was (72.3±1.2)% vs (66.0±1.4)% (P<0.05). [Conclusion] Compared with the original preparation process, the hemoglobin extraction process which optimized through orthogonal experiments greatly reduces the cell membrane fragmentation rate and minimizes the entry of cell membrane matrix into the target solution, ensuring a slightly higher hemoglobin dissolution rate, and reducing the preparation difficulty for the subsequent cell membrane separation and further purification.

AIM: To delineate the specific mutation responsible for retinitis pigmentosa(RP)in a Yi pedigree, and to analyze the correlation of RHO gene mutation with clinical phenotype.METHODS:A comprehensive clinical evaluation was conducted on the proband diagnosed with RP and other familial members, complemented by a thorough ophthalmic examination. Peripheral blood samples were obtained from the proband and familial members, from which genomic DNA was extracte. Subsequent whole exome sequencing(WES)was employed to identify the variant genes in the proband. The identified variant gene was validated through Sanger sequencing, then an in-depth analysis of the mutation genes was carried out using genetic databases to ascertain the pathogenic mutation sites. Furthermore, an exhaustive analysis was performed to delineate the genotype and phenotype characteristics.RESULTS:The RP pedigree encompasses 5 generations with 42 members, including 19 males and 23 females. A total of 13 cases of RP were identified, consisting of 4 males and 9 females, which conforms to the autosomal dominant inheritance pattern. The clinical features of this family include an early onset age, rapid progression, and a more severe condition. The patients were found to have night blindness around 6 years old, representing the earliest reported case of night blindness in RP families. The retina was manifested by progressive osteocytoid pigmentation of the fundus, a reduced visual field, and significantly decreased or even vanished a and b amplitudes of ERG. The combined results of WES and Sanger sequencing indicated that the proband had a heterozygous missense mutation of the RHO gene c.1040C>T:p.P347L, where the 1 040 base C of cDNA was replaced by T, causing codon 347 to encode leucine instead of proline. Interestingly, this mutation has not been reported in the Chinese population.CONCLUSION:This study confirmed that the mutant gene of RP in a Yi nationality pedigree was RHO(c.1040C>T). This variant leads to the change of codon 347 from encoding proline to encoding leucine, resulting in a severe clinical phenotype among family members. This study provides a certain molecular, clinical, and genetic basis for genetic counseling and gene diagnosis of RHO.

AIM: To delineate the specific mutation responsible for retinitis pigmentosa(RP)in a Yi pedigree, and to analyze the correlation of RHO gene mutation with clinical phenotype.METHODS:A comprehensive clinical evaluation was conducted on the proband diagnosed with RP and other familial members, complemented by a thorough ophthalmic examination. Peripheral blood samples were obtained from the proband and familial members, from which genomic DNA was extracte. Subsequent whole exome sequencing(WES)was employed to identify the variant genes in the proband. The identified variant gene was validated through Sanger sequencing, then an in-depth analysis of the mutation genes was carried out using genetic databases to ascertain the pathogenic mutation sites. Furthermore, an exhaustive analysis was performed to delineate the genotype and phenotype characteristics.RESULTS:The RP pedigree encompasses 5 generations with 42 members, including 19 males and 23 females. A total of 13 cases of RP were identified, consisting of 4 males and 9 females, which conforms to the autosomal dominant inheritance pattern. The clinical features of this family include an early onset age, rapid progression, and a more severe condition. The patients were found to have night blindness around 6 years old, representing the earliest reported case of night blindness in RP families. The retina was manifested by progressive osteocytoid pigmentation of the fundus, a reduced visual field, and significantly decreased or even vanished a and b amplitudes of ERG. The combined results of WES and Sanger sequencing indicated that the proband had a heterozygous missense mutation of the RHO gene c.1040C>T:p.P347L, where the 1 040 base C of cDNA was replaced by T, causing codon 347 to encode leucine instead of proline. Interestingly, this mutation has not been reported in the Chinese population.CONCLUSION:This study confirmed that the mutant gene of RP in a Yi nationality pedigree was RHO(c.1040C>T). This variant leads to the change of codon 347 from encoding proline to encoding leucine, resulting in a severe clinical phenotype among family members. This study provides a certain molecular, clinical, and genetic basis for genetic counseling and gene diagnosis of RHO.

Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.

Electromagnetic fields can regulate the fundamental biological processes involved in bone remodeling. As a non-invasive physical therapy, electromagnetic fields with specific parameters have demonstrated therapeutic effects on bone remodeling diseases, such as fractures and osteoporosis. Electromagnetic fields can be generated by the movement of charged particles or induced by varying currents. Based on whether the strength and direction of the electric field change over time, electromagnetic fields can be classified into static and time-varying fields. The treatment of bone remodeling diseases with static magnetic fields primarily focuses on fractures, often using magnetic splints to immobilize the fracture site while studying the effects of static magnetic fields on bone healing. However, there has been relatively little research on the prevention and treatment of osteoporosis using static magnetic fields. Pulsed electromagnetic fields, a type of time-varying field, have been widely used in clinical studies for treating fractures, osteoporosis, and non-union. However, current clinical applications are limited to low-frequency, and research on the relationship between frequency and biological effects remains insufficient. We believe that different types of electromagnetic fields acting on bone can induce various “secondary physical quantities”, such as magnetism, force, electricity, acoustics, and thermal energy, which can stimulate bone cells either individually or simultaneously. Bone cells possess specific electromagnetic properties, and in a static magnetic field, the presence of a magnetic field gradient can exert a certain magnetism on the bone tissue, leading to observable effects. In a time-varying magnetic field, the charged particles within the bone experience varying Lorentz forces, causing vibrations and generating acoustic effects. Additionally, as the frequency of the time-varying field increases, induced currents or potentials can be generated within the bone, leading to electrical effects. When the frequency and power exceed a certain threshold, electromagnetic energy can be converted into thermal energy, producing thermal effects. In summary, external electromagnetic fields with different characteristics can generate multiple physical quantities within biological tissues, such as magnetic, electric, mechanical, acoustic, and thermal effects. These physical quantities may also interact and couple with each other, stimulating the biological tissues in a combined or composite manner, thereby producing biological effects. This understanding is key to elucidating the electromagnetic mechanisms of how electromagnetic fields influence biological tissues. In the study of electromagnetic fields for bone remodeling diseases, attention should be paid to the biological effects of bone remodeling under different electromagnetic wave characteristics. This includes exploring innovative electromagnetic source technologies applicable to bone remodeling, identifying safe and effective electromagnetic field parameters, and combining basic research with technological invention to develop scientifically grounded, advanced key technologies for innovative electromagnetic treatment devices targeting bone remodeling diseases. In conclusion, electromagnetic fields and multiple physical factors have the potential to prevent and treat bone remodeling diseases, and have significant application prospects.

ObjectivePhotoacoustic pump-probe imaging can effectively eliminate the interference of blood background signal in traditional photoacoustic imaging, and realize the imaging of weak phosphorescence molecules and their triplet lifetimes in deep tissues. However, background differential noise in photoacoustic pump-probe imaging often leads to large fitting results of phosphorescent molecule concentration and triplet lifetime. Therefore, this paper proposes a novel triplet lifetime fitting method for photoacoustic pump-probe imaging. By extracting the phase of the triplet differential signal and the background noise, the fitting bias caused by the background noise can be effectively corrected. MethodsThe advantages and feasibility of the proposed algorithm are verified by numerical simulation, phantom and in vivo experiments, respectively. ResultsIn the numerical simulation, under the condition of noise intensity being 10% of the signal amplitude, the new method can optimize the fitting deviation from 48.5% to about 5%, and has a higher exclusion coefficient (0.88>0.79), which greatly improves the fitting accuracy. The high specificity imaging ability of photoacoustic pump imaging for phosphorescent molecules has been demonstrated by phantom experiments. In vivo experiments have verified the feasibility of the new fitting method proposed in this paper for fitting phosphoometric lifetime to monitor oxygen partial pressure content during photodynamic therapy of tumors in nude mice. ConclusionThis work will play an important role in promoting the application of photoacoustic pump-probe imaging in biomedicine.

[Objective] To investigate the protective effect of Salvia miltiorrhiza injection (SMI) on the kidneys of HBOC-CHP01 resuscitated haemorrhagic shock rats. [Methods] A 50% haemorrhagic shock rat model was established, with 12 rats divided into two groups: SMI + HBOC-CHP01 group and HBOC-CHP01 group, with 6 rats in each group. The rats in the SMI+ HBOC-CHP01 group were given an equal volume of HBOC-CHP01 for resuscitation after haemorrhagic shock, and an 8 mL/kg dose of SMI. Rats in the HBOC-CHP01 group were resuscitated by administering an equilibrium blood loss volume of HBOC-CHP01 and given an 8 mL/kg dose of 0.9% NaCl solution. Blood was taken from rats at five points: before bloodletting (baseline), during haemorrhagic shock (HS), immediately after resuscitation (RS0h), 1 h after resuscitation (RS1h), and 24 h after resuscitation (RS24h). A blood gas analyser was used to detect the lactate level (Lac), glucose content (Glu), residual base (BEecf), pH, bicarbonate (HCO3-), high iron haemoglobin (MetHb). White blood cells (WBC), platelets (PLT), haemoglobin content (Hb), carboxyhaemoglobin (COHb) were detected using a quintuple classification. Blood creatinine (SCr), uric acid (UA), kidney-related indexes were detected using biochemistry instrument. Kidney tissues of the rats were taken after 24 h of resuscitation and after execution, and the inflammation of kidneys of the rats of the two groups was analyzed using HE staining. Fluorescence staining was used to detect the level of ROS in the kidneys of rats in both groups. [Results] At RS 0h, the Beecf, Glu and Lac levels of rats in the SMI+HBOC-CHP01 group were significantly lower than those of rats in the HBOC-CHP01 group, and the pH level of rats in the SMI+HBOC-CHP01 group was significantly higher than that of rats in the HBOC-CHP01 group, and the Glu levels of rats in the SMI+HBOC-CHP01 group were significantly lower than those of rats in the HBOC-CHP01 group at RS 1h. At RS 0h, the WBC, PLT and COHb contents of rats in the SMI+HBOC-CHP01 group were all significantly higher than those of rats in the HBOC-CHP01 group, and at RS 1h, the WBC content of rats in the SMI+HBOC-CHP01 group was significantly higher than that of rats in the HBOC-CHP01 group; at RS 1h, the UA content of rats in the SMI+HBOC-CHP01 group was significantly lower than that of rats in the HBOC-CHP01 group; at RS 24h, the SCr content of rats in the SMI+HBOC-CHP01 group was significantly lower than that of rats in the HBOC-CHP01 group; at RS 24h, the inflammation level of kidney tissues of rats in the SMI+HBOC-CHP01 group was significantly lower than that of rats in the HBOC -CHP01 group rats, and the ROS and MPO levels in the kidney tissues of rats in the SMI+HBOC-CHP01 group were significantly lower than those of rats in the HBOC-CHP01 group. [Conclusion] The combination of Salvia miltiorrhiza injection during the resuscitation of rats with severe haemorrhagic shock by HBOC-CHP01 can alleviate renal injury by reducing inflammatory response and oxidative stress.

ObjectiveTo evaluate the clinical efficacy and safety of Baoshen prescription in the treatment of stage Ⅳ diabetic nephropathy （DN） in the patients with syndromes of Qi-Yin deficiency and kidney collateral stasis and obstruction， and to explore the mechanism of this prescription delaying the disease progression. MethodsA randomized， controlled， double-blind， multicenter clinical trial was conducted， in which 94 stage Ⅳ DN patients with syndromes of Qi-Yin deficiency and kidney collateral stasis and obstruction were randomly assigned into Baoshen prescription and control groups （47 cases）. The treatment lasted for 12 weeks. The primary efficacy indicators were mainly renal function indexes， including urine albumin-to-creatinine ratio （UACR）， 24-hour urine total protein （24 h-UTP）， serum creatinine （SCr）， and estimated glomerular filtration rate （eGFR）. The secondary efficacy indicators were metabolic memory of hyperglycemia， podocyte epithelial-to-mesenchymal transdifferentiation-related indexes， and TCM syndrome score. ResultsAfter 12 weeks of treatment， the Baoshen prescription group showed lowered levels of advanced glycation end products （lgAGEs）， connective tissue growth factor （CTGF）， type Ⅳ collagen （Col-Ⅳ）， receptor of AGEs （RAGE）， urinary fibroblast-specific protein-1 （FSP-1）， UACR， 24 h-UTP， and glycated hemoglobin （HbAlc） （P<0.05）， and an upward trend of miR-21 mRNA. The control group showed elevated levels of SCr and UREA and lowered levels of urinary FSP-1， eGFR， and HbAlc （P<0.05）. After treatment， the Baoshen prescription group had lower levels of lgAGEs， CTGF， urinary FSP-1， SCr， UACR， and 24 h-UTP and higher levels of Col-Ⅳ and eGFR than the control group （P<0.05）. In addition， the Baoshen prescription group showed statistically significant differences in SCr， eGFR， UACR， and 24 h-UTP before and after treatment （P<0.05）. ConclusionBaoshen prescription can effectively improve the renal function， reduce the urinary protein level， and alleviate clinical symptoms in stage Ⅳ DN patients with syndromes of Qi-Yin deficiency and kidney collateral stasis and obstruction. The mechanism may be related to the metabolic memory of hyperglycemia and epithelial-to-mesenchymal transdifferentiation of podocytes.

BACKGROUND:We have successfully established an animal model of small ear pig in southern Yunnan province with internal tension relieving technique combined with autologous Achilles tendon for anterior cruciate ligament reconstruction,and verified the stability and reliability of the model.However,whether internal tension relieving technique can promote the ligamentalization process of autologous Achilles tendon graft has not been studied. OBJECTIVE:To investigate the differences in the process of ligamentalization between conventional reconstruction and internal reduction reconstruction of the anterior cruciate ligament by gross view,histology and electron microscopy. METHODS:Thirty adult female small ear pigs in southern Yunnan province were selected.Anterior cruciate ligament reconstruction was performed on the left knee joint with the ipsilateral knee Achilles tendon(n=30 in the normal group),and anterior cruciate ligament reconstruction was performed on the right knee joint with the ipsilateral knee Achilles tendon combined with the internal relaxation and enhancement system(n=30 in the relaxation group).The autogenous right forelimb was used as the control group;the anterior cruciate ligament was exposed but not severed or surgically treated.At 12,24,and 48 weeks after surgery,10 animals were sacrificed,respectively.The left and right knee joint specimens were taken for gross morphological observation to evaluate the graft morphology.MAS score was used to evaluate the excellent and good rate of the ligament at each time point.Hematoxylin-eosin staining was used to evaluate the degree of ligament graft vascularization.Collagen fibers and nuclear morphology were observed,and nuclear morphology was scored.Ultrastructural remodeling was evaluated by scanning electron microscopy and transmission electron microscopy. RESULTS AND CONCLUSION:(1)The ligament healing shape of the relaxation group was better at various time points after surgery,and the excellent and good rate of MAS score was higher(P<0.05).Moreover,the relaxation group could obtain higher ligament vascularization score(P<0.05).(2)The arrangement of collagen bundles and fiber bundles in the two groups gradually tended to be orderly,and the transverse fiber connections between collagen gradually increased and thickened,suggesting that the strength and shape degree of the grafts were gradually improved,but the ligament remodeling in the relaxation group was always faster than that in the normal group at various time points after surgery.(3)The diameter,distribution density,and arrangement degree of collagen fibers in the relaxation group were better than those in the normal group at all time points,especially in the comparison of collagen fiber diameter between and within the relaxation group(P<0.05).