Effects of mesenchymal stem cell on dopaminergic neurons,motor and memory functions in animal models of Parkinson's disease:a systematic review and meta-analysis

Parkinson’s disease is chara cterized by the loss of dopaminergic neurons in the substantia nigra pars com pacta,and although restoring striatal dopamine levels may improve symptoms,no treatment can cure or reve rse the disease itself.Stem cell therapy has a regenerative effect and is being actively studied as a candidate for the treatment of Parkinson’s disease.Mesenchymal stem cells are considered a promising option due to fewer ethical concerns,a lower risk of immune rejection,and a lower risk of teratogenicity.We performed a meta-analysis to evaluate the therapeutic effects of mesenchymal stem cells and their derivatives on motor function,memory,and preservation of dopamine rgic neurons in a Parkinson’s disease animal model.We searched bibliographic databases(PubMed/MEDLINE,Embase,CENTRAL,Scopus,and Web of Science)to identify articles and included only pee r-reviewed in vivo interve ntional animal studies published in any language through J une 28,2023.The study utilized the random-effect model to estimate the 95%confidence intervals(CI)of the standard mean differences(SMD)between the treatment and control groups.We use the systematic review center for laboratory animal expe rimentation’s risk of bias tool and the collaborative approach to meta-analysis and review of animal studies checklist for study quality assessment.A total of 33studies with data from 840 Parkinson’s disease model animals were included in the meta-analysis.Treatment with mesenchymal stem cells significantly improved motor function as assessed by the amphetamine-induced rotational test.Among the stem cell types,the bone marrow MSCs with neurotrophic factor group showed la rgest effect size(SMD[95%CI]=-6.21[-9.50 to-2.93],P=0.0001,I^(2)=0.0%).The stem cell treatment group had significantly more tyrosine hydroxylase positive dopamine rgic neurons in the striatum([95%CI]=1.04[0.59 to 1.49],P=0.0001,I^(2)=65.1%)and substantia nigra(SMD[95%CI]=1.38[0.89 to 1.87],P=0.0001,I^(2)=75.3%),indicating a protective effect on dopaminergic neurons.Subgroup analysis of the amphetamine-induced rotation test showed a significant reduction only in the intracranial-striatum route(SMD[95%CI]=-2.59[-3.25 to-1.94],P=0.0001,I^(2)=74.4%).The memory test showed significant improvement only in the intravenous route(SMD[95%CI]=4.80[1.84 to 7.76],P=0.027,I^(2)=79.6%).Mesenchymal stem cells have been shown to positively impact motor function and memory function and protect dopaminergic neurons in preclinical models of Parkinson’s disease.Further research is required to determine the optimal stem cell types,modifications,transplanted cell numbe rs,and delivery methods for these protocols.

Acute liver failure:A systematic review and network meta-analysis of optimal type of stem cells in animal models

BACKGROUND The therapeutic effects of various stem cells in acute liver failure(ALF)have been demonstrated in preclinical studies.However,the specific type of stem cells with the highest therapeutic potential has not been determined.AIM To validate the efficacy of stem cells in ALF model and to identify the most promising stem cells.METHODS A search was conducted on the PubMed,Web of Science,Embase,Scopus,and Cochrane databases from inception to May 3,2022,and updated on November 16,2022 to identify relevant studies.Two independent reviewers performed the literature search,identification,screening,quality assessment,and data extraction.RESULTS A total of 89 animal studies were included in the analysis.The results of traditional meta-analysis showed that stem cell therapy could significantly reduce the serum levels of alanine aminotransferase[weighted mean difference(WMD)=-181.05(-191.71,-170.39)],aspartate aminotransferase[WMD=-309.04(-328.45,-289.63)],tumor necrosis factor-alpha[WMD=-8.75(-9.93,-7.56)],and interleukin-6[WMD=-10.43(-12.11,-8.76)]in animal models of ALF.Further subgroup analysis and network meta-analysis showed that although mesenchymal stem cells are the current research hotspot,the effect of liver stem cells(LSCs)on improving liver function is significantly better than that of the other five types of stem cells.In addition,the ranking results showed that the possibility of LSCs improving liver function ranked first.This fully proves the great therapeutic potential of LSCs,which needs to be paid more attention in the future.CONCLUSION LSCs may have a higher therapeutic potential.Further high-quality animal experiments are needed to explore the most effective stem cells for ALF.

Mesenchymal stem cells in the treatment of inflammatory and autoimmune diseases in experimental animal models

Multipotent mesenchymal stromal cells [also known as mesenchymal stem cells(MSCs)] are currently being studied as a cell-based treatment for inflammatory disorders. Experimental animal models of human immune-mediated diseases have been instrumental in establishing their immunosuppressive properties. In this review, we summarize recent studies examining the effectiveness of MSCs as immunotherapy in several widely-studied animal models, including type 1 diabetes, experimental autoimmune arthritis, experimental autoimmune encephalomyelitis, inflammatory bowel disease, graft-vs-host disease, and systemic lupus erythematosus. In addition, we discuss mechanisms identified by which MSCs mediate immune suppression in specific disease models, and potential sources of functional variability of MSCs between studies.

Challenges in animal modelling of mesenchymal stromal cell therapy for inflammatory bowel disease

Utilization of mesenchymal stromal cells(MSCs) for the treatment of Crohn's disease and ulcerative colitis is of translational interest.Safety of MSC therapy has been well demonstrated in early phase clinical trials but efficacy in randomized clinical trials needs to be demonstrated.Understanding MSC mechanisms of action to reduce gut injury and inflammation is necessary to improve current ongoing and future clinical trials.However, two major hurdles impede the direct translation of data derived from animal experiments to the clinical situation:(1) limitations of the currently available animal models of colitis that reflect human inflammatory bowel diseases(IBD).The etiology and progression of human IBD are multifactorial and hence a challenge to mimic in animal models; and(2) Species specific differences in the functionality of MSCs derived from mice versus humans.MSCs derived from mice and humans are not identical in their mechanisms of action in suppressing inflammation.Thus, preclinical animal studies with murine derived MSCs cannot be considered as an exact replica of human MSC based clinical trials.In the present review, we discuss the therapeutic properties of MSCs in preclinical and clinical studies of IBD.We also discuss the challenges and approaches of using appropriate animal models of colitis, not only to study putative MSC therapeutic efficacy and their mechanisms of action, but also the suitability of translating findings derived from such studies to the clinic.

Induced pluripotent stem cells: Mechanisms, achievements and perspectives in farm animals

Pluripotent stem cells are unspecialized cells withunlimited self-renewal, and they can be triggered to differentiate into desired specialized cell types. These features provide the basis for an unlimited cell source for innovative cell therapies. Pluripotent cells also allow to study developmental pathways, and to employ them or their differentiated cell derivatives in pharmaceutical testing and biotechnological applications. Via blastocyst complementation, pluripotent cells are a favoured tool for the generation of genetically modified mice. The recently established technology to generate an induced pluripotency status by ectopic co-expression of the transcription factors Oct4, Sox2, Klf4 and c-Myc allows to extending these applications to farm animal species, for which the derivation of genuine embryonic stem cells was not successful so far. Most induced pluripotent stem(i PS) cells are generated by retroviral or lentiviral transduction of reprogramming factors. Multiple viral integrations into the genome may cause insertional mutagenesis and may increase the risk of tumour formation. Non-integration methods have been reported to overcome the safety concerns associated with retro and lentiviral-derived i PS cells, such as transient expression of the reprogramming factors using episomal plasmids, and direct delivery of reprogramming m RNAs or proteins. In this review, we focus on the mechanisms of cellular reprogramming and current methods used to induce pluripotency. We also highlight problems associated with the generation of i PS cells. An increased understanding of the fundamental mechanisms underlying pluripotency and refining the methodology of i PS cell generation will have a profound impact on future development and application in regenerative medicine and reproductive biotechnology of farm animals.

Neuroprotective Effects of Sodium Ferulate and Its Antidepressant-Like Effect Measured by Acute and Chronic Experimental Methods in Animal Models of Depression

Antidepressants with novel targets and without side effects are in great demand. Ferulic acid (FA) is a ubiquitous phenolic acid of low toxicity, and sodium ferulate (SF) is its sodium salt. Our previous studies have revealed that FA and SF show significant protective effect on excitotoxicity, we now test its potential neuroprotective and antidepressant-like effects. MTT assay and morphological analysis by fluorescence microscopy were adopted to measure the neuroprotective effects of SF;forced-swimming, tail-suspension, and chronic mild stress (CMS) tests were performed to assess its antidepressant-like activity. The results showed that SF had protection against H2O2-induced oxidative damage and dexamethasone (DXM)-induced neurotoxicity pheochromocytoma (PC12) cells. Acute administration of SF markedly decreased the duration of immobility during forced-swimming in rats and mice and tail-supension tests in mice. However, SF has no any effects on reserpine-induced hypothermia, 5-hydroxytryptophan-induced head-twitch response, and potentiation of noradrenaline toxicity in mice. Chronic administration of SF reversed the effects of CMS on consumption of food and sucrose solution, weight gain, and histopathology of hippocampus by light microscopy, and potently shortened the immobility time during forced-swimming test following CMS in rats. This study provides evidence that SF possesses obviously antidepressant-like activity, and the antidepressant-like effect may result from its neuroprotective effects.

Mechanism of hyperproteinemia-induced blood cell homeostasis imbalance in an animal model

Hyperproteinemia is a metabolic disorder associated with increased plasma protein concentration(PPC)and is often clinically complicated by malignant diseases or severe infections.At present,however,research on the molecular mechanism underlying high PPC(HPPC)is scant.Here,an animal model of primary hyperproteinemia was constructed in an invertebrate(Bombyx mori)to investigate the effects of HPPC on circulating blood cells.Results showed that HPPC affected blood cell homeostasis,leading to increased reactive oxygen species levels,and induced programmed cell death dependent on the endoplasmic reticulum-calcium ion signaling pathway.HPPC induced the proliferation of blood cells,mainly granulocytes,by activating the Janus kinase/signal transducer and activator of transcription(JAK/STAT)signaling pathway.Supplementation with the endocrine hormone active substance 20 E significantly reduced the impact of HPPC on blood cell homeostasis.Thus,we identified a novel signaling pathway by which HPPC affects blood cell homeostasis,which differs from hyperglycemia,hyperlipidemia,and hypercholesterolemia.In addition,we showed that down-regulation of gene expression of the hematopoietic factor Gcm could be used as a potential early detection indicator for hyperproteinemia.

Effect of Traditional Chinese Medicine Antiviral Capsules On Animal Model Genital Herpes and HSV-2 in Cell Culture

Objective: To study the effect of traditional Chinese medicine antiviral capsules in the treatment of genital herpes. Methods: Using female guinea pig genital herpes as the animal model, this study used oral administration of two formulations of antiviral capsules (AC) and observed the effect on vaginal HSV-2 titers and vulvar symptoms. Cell cultures were also used to examine the direct inactivation of HSV-2 by the antiviral capsules and the suppression of HSV-2 via three drug administration methods. Results: There was no significant difference of mean vaginal virus titers between the antiviral capsule groups and that of the positive acyclovir (ACV) control (P>0.05). Mean vulvarsymptom scores of the two antiviral capsule groups were also significantly lower than that of the saline negative control group on days 2, 3, 5, 7 and 8 (P<0.05) and similar to that of the ACV control (P>0.05). Cell culture showed the minimum inhibitory concentrations of antiviral capsules No. 1 and No. 2 were 0.390625 mg/ml and 1.5625 mg/ml, respectively. Conclusion: The traditional Chinese medicine antiviral capsules had suppressive effects on HSV-2 in both animal model GH and in vitro cell culture.

Experimental animal models and infl ammatory cellular changes in cerebral ischemic and hemorrhagic stroke

Stroke, including cerebral ischemia, intracerebral hemorrhage, and subarachnoid hemorrhage, is the leading cause of long-term disability and death worldwide. Animal models have greatly contributed to our understanding of the risk factors and the pathophysiology of stroke, as well as the development of therapeutic strategies for its treatment. Further development and investigation of experimental models, however, are needed to elucidate the pathogenesis of stroke and to enhance and expand novel therapeutic targets. In this article, we provide an overview of the characteristics of commonly-used animal models of stroke and focus on the inflammatory responses to cerebral stroke, which may provide insights into a framework for developing effective therapies for stroke in humans.

Cell reprogramming therapy for Parkinson’s disease

Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic neurons to treat Parkinson’s disease.The initial strategy for cell replacement therapy used human fetal ventral midbrain and human embryonic stem cells to treat Parkinson’s disease,which could substantially alleviate the symptoms of Parkinson’s disease in clinical practice.However,ethical issues and tumor formation were limitations of its clinical application.Induced pluripotent stem cells can be acquired without sacrificing human embryos,which eliminates the huge ethical barriers of human stem cell therapy.Another widely considered neuronal regeneration strategy is to directly reprogram fibroblasts and astrocytes into neurons,without the need for intermediate proliferation states,thus avoiding issues of immune rejection and tumor formation.Both induced pluripotent stem cells and direct reprogramming of lineage cells have shown promising results in the treatment of Parkinson’s disease.However,there are also ethical concerns and the risk of tumor formation that need to be addressed.This review highlights the current application status of cell reprogramming in the treatment of Parkinson’s disease,focusing on the use of induced pluripotent stem cells in cell replacement therapy,including preclinical animal models and progress in clinical research.The review also discusses the advancements in direct reprogramming of lineage cells in the treatment of Parkinson’s disease,as well as the controversy surrounding in vivo reprogramming.These findings suggest that cell reprogramming may hold great promise as a potential strategy for treating Parkinson’s disease.

Transplantation of bone marrow mesenchymal stem cells improves cognitive deficits and alleviates neuropathology in animal models of Alzheimer’s disease: a meta-analytic review on potential mechanisms

Background Alzheimer’s disease is a neurodegenerative disorder.Therapeutically,a transplantation of bone marrow mesenchymal stem cells(BMMSCs)can play a beneficial role in animal models of Alzheimer’s disease.However,the relevant mechanism remains to be fully elucidated.Main body Subsequent to the transplantation of BMMSCs,memory loss and cognitive impairment were significantly improved in animal models with Alzheimer’s disease(AD).Potential mechanisms involved neurogenesis,apoptosis,angiogenesis,inflammation,immunomodulation,etc.The above mechanisms might play different roles at certain stages.It was revealed that the transplantation of BMMSCs could alter some gene levels.Moreover,the differential expression of representative genes was responsible for neuropathological phenotypes in Alzheimer’s disease,which could be used to construct gene-specific patterns.Conclusions Multiple signal pathways involve therapeutic mechanisms by which the transplantation of BMMSCs improves cognitive and behavioral deficits in AD models.Gene expression profile can be utilized to establish statistical regression model for the evaluation of therapeutic effect.The transplantation of autologous BMMSCs maybe a prospective therapy for patients with Alzheimer’s disease.

Effectiveness and mechanisms of adiposederived stem cell therapy in animal models of Parkinson’s disease:a systematic review and meta-analysis

Animal models provide an opportunity to assess the optimal treatment way and the underlying mechanisms of direct clinical application of adipose-derived stem cells(ADSCs).Previous studies have evaluated the effects of primitive and induced ADSCs in animal models of Parkinson’s disease(PD).Here,eight databases were systematically searched for studies on the effects and in vivo changes caused by ADSC intervention.Quality assessment was conducted using a 10-item risk of bias tool.For the subsequent meta-analysis,study characteristics were extracted and effect sizes were computed.Ten out of 2324 published articles(n=169 animals)were selected for further meta-analysis.After ADSC therapy,the rotation behavior(10 experiments,n=156 animals)and rotarod performance(3 experiments,n=54 animals)were improved(P<0.00001 and P=0.0003,respectively).The rotation behavior test reflected functional recovery,which may be due to the neurogenesis from neuronally differentiated ADSCs,resulting in a higher pooled effect size of standard mean difference(SMD)(−2.59;95%CI,−3.57 to−1.61)when compared to that of primitive cells(−2.18;95%CI,−3.29 to−1.07).Stratified analyses by different time intervals indicated that ADSC intervention exhibited a long-term effect.Following the transplantation of ADSCs,tyrosine hydroxylase-positive neurons recovered in the lesion area with pooled SMD of 13.36[6.85,19.86].Transplantation of ADSCs is a therapeutic option that shows long-lasting effects in animal models of PD.The potential mechanisms of ADSCs involve neurogenesis and neuroprotective effects.The standardized induction of neural form of transplanted ADSCs can lead to a future application in clinical practice.

Therapeutic effects of dental pulp stem cells on vascular dementia in rat models

Dental pulp stem cells are a type of adult stem cells with strong proliferative ability and multi-differentiation potential. There are no studies on treatment of vascular dementia with dental pulp stem cells. In the present study, rat models of vascular dementia were established by two-vessel occlusion, and 30 days later, rats were injected with 2 × 10^(7) dental pulp stem cells via the tail vein. At 70 days after vascular dementia induction, dental pulp stem cells had migrated to the brain tissue of rat vascular dementia models and differentiated into neuronlike cells. At the same time, doublecortin, neurofilament 200, and Neu N m RNA and protein expression levels in the brain tissue were increased, and glial fibrillary acidic protein m RNA and protein expression levels were decreased. Behavioral testing also revealed that dental pulp stem cell transplantation improved the cognitive function of rat vascular dementia models. These findings suggest that dental pulp stem cell transplantation is effective in treating vascular dementia possibly through a paracrine mechanism. The study was approved by the Animal Ethics Committee of Harbin Medical University(approval No. KY2017-132) in 2017.

Stem cell therapy for Alzheimer’s disease:An overview of experimental models and reality

Alzheimer's disease(AD)is a neurodegenerative disorder.The pathology of AD is characterized by extracellular amyloid beta(Aβ)plaques,neurofibrillary tangles com-posed of hyperphosphorylated tau,neuronal death,synapse loss,and brain atrophy.Many therapies have been tested to improve or at least effectively modify the course of AD.Meaningful data indicate that the transplantation of stem cells can alleviate neuropathology and significantly ameliorate cognitive deficits in animal models with Alzheimer's disease.Transplanted stem cells have shown their inherent advantages in improving cognitive impairment and memory dysfunction,although certain weak-nesses or limitations need to be overcome.This review recapitulates rodent models for AD,the therapeutic efficacy of stem cells,influencing factors,and the underlying mechanisms behind these changes.Stem cell therapy provides perspective and chal-lenges for its clinical application in the future.

Metastatic human hepatocellular carcinoma models in nude mice and cell line with metastatic potential

Metastatic human HCC model is needed for the studies on mechanism and intervention of metastatic recurrence. By using orthotopic implantation of histologically intact tissues of 30 surgical specimens, a patient like metastatic model of human HCC in nude mice (LCI-D20)and a Iow metastatic model of human HCC in nude mice LCI-D35 ) have been established. All mice with transplanted LCI-D20 tumors exhibited extremely high metastatic ability including spontaneous metastasis to liver, lungs, lymph nodes and peritoneal seeding.Remarkable difference was also found in expression of some of the invasiveness related genes and growth factors between the LCI-D20 and LCI-D35 tumors. PAI-Iincreased gradually following tumor progression in LCID20 model, and correlated with tumor size and AFP level,Phasic expression of tissue intercellular adhesion molecule-I in this model was also observed. Using corneal micropocket model, it was demonstrated that the vascular response induced by LCI-D20 tumor was stronger than that induced by LCI-D35 tumor. Similar report on metastatic human HCC model in nude mice and human HCC cell line with metastatic potential was rarely found in the literature. This LCI-D20 model has been widely used for the studies on intervention of metastasis, including antiangiogenesis, antisense approach, metalloproteinase inhibitor, differentiation inducer, etc. It is concluded that the establishment of metastatic human HCC model in nude mice and human HCC cell line with metastatic potential will provide important models for the in vivo and in vitro study of HCC invasiveness, angiogenesis as well as intervention of HCC recurrence.

Neuroprotective effect of mesenchymal stem cellderived extracellular vesicles on optic nerve injury in chronic ocular hypertension

Mesenchymal stem cells have neuroprotective effects that limit damage to the retina and photoreceptors,and which may be mediated by extracellular vesicles(or exosomes)released by mesenchymal stem cells.To investigate the neuroprotective effect of extracellular vesicles derived from umbilical cord mesenchymal stem cells on glaucoma,we established rat models of chronic ocular hypertension by injecting conjunctival fibroblasts into the anterior chamber to mimic optic nerve injury caused by glaucoma.One week after injury,extracellular vesicles derived from umbilical cord-derived mesenchymal stem cells were injected into the vitreous cavity.We found that extracellular vesicles derived from mesenchymal stem cells substantially reduced retinal damage,increased the number of retinal ganglion cells,and inhibited the activation of caspase-3.These findings suggest that mesenchymal stem cell-derived extracellular vesicles can help alleviate optic nerve injury caused by chronic ocular hypertension,and this effect is achieved by inhibiting cell apoptosis.

Malaria modeling: In vitro stem cells vs in vivo models

The recent development of stem cell research and the possibility of generating cells that can be stably and permanently modified in their genome open a broad horizon in the world of in vitro modeling. The malaria field is gaining new opportunities from this importantbreakthrough and novel tools were adapted and opened new frontiers for malaria research. In addition to the new in vitro systems, in recent years there were also significant advances in the development of new animal models that allows studying the entire cell cycle of human malaria. In this paper, we review the different protocols available to study human Plasmodium species either by using stem cell or alternative animal models.

An insight on established retinal injury mechanisms and prevalent retinal stem cell activation pathways in vertebrate models

Implementing different tools and injury mechanisms in multiple animal models of retina regeneration,researchers have discovered the existence of retinal stem/pro-genitor cells.Although they appear to be distributed uniformly across the vertebrate lineage,the reparative potential of the retina is mainly restricted to lower vertebrates.Regenerative repair post-injury requires the creation of a proliferative niche,vital for proper stem cell activation,propagation,and lineage differentiation.This seems to be lacking in mammals.Hence,in this review,we first discuss the many forms of retinal injuries that have been generated using animal models.Next,we discuss how they are utilized to stimulate regeneration and mimic eye disease pathologies.The key to driving stem cell activation in mammals relies on the information we can gather from these models.Lastly,we present a brief update about the genes,growth factors,and signaling pathways that have been brought to light using these models.

Towards system genetics analysis of head and neck squamous cell carcinoma using the mouse model,cellular platform,and clinical human data

Head and neck squamous cell cancer(HNSCC)is a leading global malignancy.Every year,More than 830000 people are diagnosed with HNSCC globally,with more than 430000 fatalities.HNSCC is a deadly diverse malignancy with many tumor locations and biological characteristics.It originates from the squamous epithelium of the oral cavity,oropharynx,nasopharynx,larynx,and hypopharynx.The most frequently impacted regions are the tongue and larynx.Previous investigations have demonstrated the critical role of host genetic susceptibility in the progression of HNSCC.Despite the advances in our knowledge,the improved survival rate of HNSCC patients over the last 40 years has been limited.Failure to identify the molecular origins of development of HNSCC and the genetic basis of the disease and its biological heterogeneity impedes the development of new therapeutic methods.These results indicate a need to identify more genetic factors underlying this complex disease,which can be better used in early detection and prevention strategies.The lack of reliable animal models to investigate the underlying molecular processes is one of the most significant barriers to understanding HNSCC tumors.In this report,we explore and discuss potential research prospects utilizing the Collaborative Cross mouse model and crossing it to mice carrying single or double knockout genes(e.g.Smad 4 and P53 genes)to identify genetic factors affecting the development of this complex disease using genome-wide association studies,epigenetics,micro RNA,long noncoding RNA,lnc RNA,histone modifications,methylation,phosphorylation,and proteomics.

高频超声在构建SD大鼠皮下移植性乳腺癌模型中的应用

目的:应用MADB-106大鼠乳腺癌细胞悬液皮下移植法建立SD大鼠乳腺癌移植性肿瘤动物模型,并使用高频超声监测肿瘤生长情况。方法:选取7~8周龄雌性SD乳鼠16只,将处于对数生长期的MADB-106大鼠乳腺癌细胞悬液于大鼠腹股沟皮下接种,应用高频超声观察成瘤率、肿块大小、血供情况及其它声像图特征。结果:SD大鼠接种成功率为100%,死亡2只,剩余14只生长良好;超声检查肿块为类圆形,内部低回声且稍不均匀,边界尚清,后方回声衰减,彩色多普勒扫查肿块内部及周边可见较丰富血流信号;3周后切除瘤体组织,大体观肿块成灰白色,多呈椭圆形,部分边缘呈分叶状改变,肿瘤血管较丰富,镜下可见肿瘤细胞大小形状各异,核大深染,异型性明显。结论:通过MADB-106大鼠乳腺癌细胞接种于雌性SD大鼠腹股沟皮下,成功建立了大鼠乳腺癌移植性肿瘤动物模型。高频超声技术可以在SD大鼠乳腺癌皮下成瘤过程中对肿物的大小、形态、边界、内部回声及血流等生物学情况进行动态检测,是观察和评价瘤体动态变化过程的重要技术手段。