Cerebral syphilitic gumma misdiagnosed as brain abscess: A case report

BACKGROUND Cerebral syphilitic gumma is a relatively rare clinical disease.Its clinical manifest-ations are non-specific,and the imaging manifestations are similar to other in-tracranial occupying lesions,often misdiagnosed as tumors or abscesses.There are few reports on this disease in the relevant literature.To our knowledge,we have reported the first case of cerebral syphilitic gumma misdiagnosed as a brain abscess.We report this case and provide useful information for clinical doctors on neurosyphilis diseases.CASE SUMMARY We report the case to explore the diagnostic essentials of cerebral syphilitic gumma and attempt to mitigate the rates of misdiagnosis and missed diagnosis by equipping physicians with knowledge of neurosyphilis characteristics.The cli-nical diagnosis and treatment of a patient with cerebral syphilitic gumma were reported.Clinical manifestations,classifications,and diagnostic points were retro-spectively analyzed.The patient was admitted to the hospital with fever and limb weakness.Brain magnetic resonance imaging showed multiple space-occupying lesions and a positive serum Treponema pallidum gelatin agglutination test.The patient was misdiagnosed as having a brain abscess and underwent a craniotomy.A postoperative pathological diagnosis of syphilis gumma was made.The patient improved and was discharged after penicillin anti-syphilis treatment.Follow-up recovery was satisfactory.CONCLUSION Cerebral syphilitic gumma is rare in clinical practice,and it is often misdiagnosed and missed.Clinical diagnosis should be considered in combination with multiple examinations.

Brain abscess from oral microbiota approached by metagenomic next-generation sequencing: A case report and review of literature

BACKGROUND Brain abscess is a serious and potentially fatal disease caused primarily by microbial infection.Although progress has been made in the diagnosis and treatment of brain abscesses,the diagnostic timeliness of pathogens needs to be improved.CASE SUMMARY We report the case of a 54-year-old male with a brain abscess caused by oral bacteria.The patient recovered well after receiving a combination of metagenomic next-generation sequencing(mNGS)-assisted guided medication and surgery.CONCLUSION Therefore,mNGS may be widely applied to identify the pathogenic microor-ganisms of brain abscesses and guide precision medicine.

Brain abscess caused by Streptococcus anginosus group:Three case reports

BACKGROUND This case series investigated the clinical manifestations,diagnoses,and treatment of cerebral abscesses caused by Streptococcus anginosus.We retrospectively analyzed the clinical characteristics and outcomes of three cases of cerebral abscesses caused by Streptococcus anginosus and conducted a comprehensive review of relevant literature.CASE SUMMARY Case 1 presented with a history of left otitis media and exhibited high fever,confusion,and vomiting as primary symptoms.Postoperative pus culture indicated a brain abscess caused by Streptococcus constellatus infection.Case 2 experienced dizziness for two days as the primary symptom.Postoperative pus culture suggested an intermediate streptococcal brain abscess.Case 3:Enhanced head magnetic resonance imaging(MRI)and diffusion-weighted imaging revealed occupancy of the left temporal lobe,initially suspected to be a metastatic tumor.However,a postoperative pus culture confirmed the presence of a brain abscess caused by Streptococcus anginosus infection.The three cases presented in this case series were all patients with community-acquired brain abscesses resulting from angina caused by Streptococcus group infection.All three patients demonstrated sensitivity to penicillin,ceftriaxone,vancomycin,linezolid,chloramphenicol,and levofloxacin.Successful treatment was achieved through stereotaxic puncture,drainage,and ceftriaxone administration with a six-week course of antibiotics.CONCLUSION Preoperative enhanced head MRI plays a critical role in distinguishing brain tumors from abscesses.Selecting the correct early diagnostic methods for brain abscesses and providing timely intervention are very important.This case series was in accordance with the CARE guidelines.

Isolated cerebral mucormycosis that looks like stroke and brain abscess:A case report and review of the literature

BACKGROUND Cerebral mucormycosis is an infectious disease of the brain caused by fungi of the order Mucorales.These infections are rarely encountered in clinical practice and are often misdiagnosed as cerebral infarction or brain abscess.Increased mortality due to cerebral mucormycosis is closely related to delayed diagnosis and treatment,both of which present unique challenges for clinicians.CASE SUMMARY Cerebral mucormycosis is generally secondary to sinus disease or other disseminated disease.However,in this retrospective study,we report and analyze a case of isolated cerebral mucormycosis.CONCLUSION The constellation of symptoms including headaches,fever,hemiplegia,and changes in mental status taken together with clinical findings of cerebral infarction and brain abscess should raise the possibility of a brain fungal infection.Early diagnosis and prompt initiation of antifungal therapy along with surgery can improve patient survival.

Brain Abscess after COVID-19: Case Report

As the COVID-19 pandemic progresses, complications and unusual presentations of the disease have been described. Among them, the involvement of distinct parts of the neuroaxis. We report a rare case of brain abscess in elderly after SARS-Cov-2 infection readmitted in our health unit. Patient was treated with ceftriaxone, metronidazole and vancomycin with good clinical and therapeutic response. The satisfactory conduct of the case was only possible by the involvement of a multiprofessional team, which sought early diagnosis, surgical intervention and adequate duration of treatment.

Brain Abscess Surgery Outcome: A Comparison between Craniotomy with Membrane Excision versus Burr Hole Aspiration

Introduction: Brain abscess represents 8% of intracranial masses in developing countries. Despite the advances in neuro-imaging, still, the diagnosis of brain abscess is difficult and may need a biopsy in most cases to verify the diagnosis because may even lead to death. CT scan with contrast is a good tool for diagnosing and localizing brain abscesses in late stages, however, it is difficult to diagnose them in the early stages. The development of MRI helps to more accurately diagnose brain abscess. Surgical management of brain abscesses is either medical or surgical through craniotomy or burr holes. Indications of each are still a point of debate among most neurosurgeons. Methodology: This is a descriptive longitudinal prospective study to compare the outcomes of two surgical procedures used in The National Centre for Neurological Sciences-Khartoum-Sudan (NCNS) from 2012 to 2015, craniotomy and excision of the abscess membrane versus burr hole and aspiration of brain abscess in terms of duration of hospitalization, length of antibiotic use, recurrence rate, number of images needed for follow-up, and the final postoperative early and late outcomes. The data was collected through a designed questionnaire and was then analyzed using SPSS version 20. No significant ethical approval was required for this study. Results: Fifty-four patients were operated on through craniotomy (29/54) and burr hole (25/54). Their ages ranged from 1 year to 53 years with an average presentation at 13 years of age. Most patients presented with fever (23.1%), convulsions (16%), vomiting (16.7%) and headache (15.4%). The mean of illness for both groups was almost 2 months. The majority of patients in this study were having no risk factors (38.9%) while the major risk factors seen were cardiac diseases (14.8%), neurosurgical procedures (13%) and otitis media (11.1%). As most patients presented late, the diagnosis of most was made using CT brain with contrast (83.3%). In most of the patients (85.2%) there were no organisms separated in the culture. 8/54 patients had positive cultures, 7/8 were bacterial and only one (1/8) was fungal. Most patients received antibiotics for 45 days postoperatively in both craniotomy and burr hole groups. When both groups were compared, those operated with craniotomy were found to have a relatively higher length of hospital stay, however, no significant difference was found between both groups. Also, it was found that those operated on with craniotomy had a high cure rate and less recurrence in comparison with burr hole group. Deterioration and death were significantly higher among craniotomy group. Only CT brain was used as the imaging modality of choice for follow-up in both groups for 4 months’ duration and it was noted that complete evacuation was significantly higher among craniotomy group while remnants were higher among burr hole group. Conclusion: Brain abscess is still a challenging condition for neurosurgeons in Sudan. The limited number of Sudanese neurosurgeons, neurosurgical centers and diagnostic facilities contributed to delay in diagnosing brain abscess in most patients. It is important to design a strict protocol and precautions for any neurosurgical operation or bedside procedure to prevent infection and subsequent brain abscess development. CT brain with contrast is a good imaging tool for assessing the size, site and stage of brain abscesses. No significant difference between craniotomy or burr hole for clearance from brain abscess in terms of antibiotic used or duration of hospital stay. However, burr hole aspiration is associated with higher rates of recurrences. On the other hand, craniotomy and excision have relatively higher neurologic morbidity postoperative with expectantly higher post-operative hospitalization but no differences in the final outcome. Therefore, the selection of surgical technique should be individualized in each case based on the abscess site size source patient fitness for surgery and neurosurgeon’s preference.

Clinical and Radiological Features in the Cases with Cryptogenic Brain Abscess in Association with Patent Foramen Ovale: A Case Report and Review of the Literature

Brain abscesses are commonly associated with cranial trauma, a contiguous focus of infection, or hematogenous spread from a distant focus. However, no predisposing factors are identified in approximately 4% of the cases, being recognized as a cryptogenic brain abscess (CBA). Here we report a patient with a CBA in the left occipital lobe presumably caused by a periodontal disease. The patient displayed a patent foramen ovale (PFO), through which a spontaneous right-to-left shunt was revealed with transesophageal echocardiography. A literature review indicated that in contrast to cases of general brain abscesses, patients with CBA were older and mostly had dental disorders represented by periodontal diseases and a large PFO. In these patients, the abscess was located predominantly in the posterior circulation area, and their prognosis was worse than that of general cases. Consequently, we emphasize the significance of screening for PFO in cases of advanced age with CBA in the posterior circulation region. Furthermore, to avoid neurological sequelae, we suggest immediate surgical drainage with antibiotic administration and maintenance of oral hygiene.

Infective Endocarditis in Tetralogy of Fallot Complicating Brain Abscess—A Case Report

Aim: To report a case of solitary, parietal lobe abscess in a boy, aged 16 years in Tetralogy of Fallot. Introduction: Infective endocarditis is a serious and fatal complication in congenital heart disease. Following bacterial endocarditis, ventricular septal defect (VSD) and Tetralogy of Fallot (TOF) have less morbidity and higher survival rate in children. Neurological complications were recognized in 20% of cases and brain abscess is a serious infection of brain parenchyma as a result of seeding of infective pathogens in the shunted blood from the right side of the heart. Case Report: A 16 year old boy had Tetralogy of Fallot, presented with altered sensorium of sudden onset. Echocardiography revealed a large vegetation, attached to the ventricular septum and a large VSD with overriding of aorta. CT brain revealed a large abscess cavity in the parietal lobe, which was evacuated by aspiration and treated with antibiotics. Conclusion: Any patient presented with altered sensorium in cyanotic congenital heart disease must be evaluated with CT scanning for brain abscess and also check hematocrit to rule out hyperviscosity syndrome. Lumbar puncture has been considered hazardous in patients with brain abscess and usually performed under a strong suspicion of meningitis or ventriculitis in the absence of increased intracranial pressure.

Brainstem abscesses caused by Listeria monocytogenes:A case report

BACKGROUNDIntracranial Listeria infections are common in newborns and immunocompromisedindividuals, but brainstem abscesses are rare.CASE SUMMARYWe report a rare case of brainstem abscesses caused by Listeria monocytogenes in apreviously healthy adult patient. The patient’s magnetic resonance imagingexamination showed multiple brain abscesses, and his second cerebrospinal fluidculture test indicated the presence of Listeria monocytogenes. Despite earlyempirical therapy, the patient’s condition progressively deteriorated. Because thepatient's abscesses were located in the brainstem and multiple lobes, surgery wasnot possible. The patient died 40 d after admission.CONCLUSIONThis case highlights the importance of rational clinical use of drugs to avoidpotentially serious infectious complications.

Scalp block for brain abscess drainage in a patient with uncorrected tetralogy of Fallot

We report a case of an 11-year-old boy with diagnosed but uncorrected tetralogy of Fallot presented to us for brain abscess drainage. The child was managed successfully with scalp block with sedation.

Rare case of cryptogenic brain abscess caused by Raoultella ornithinolityca

Cerebral abscess is a potentially fatal neurosurgical condition,despite improvements in technology,new antimicrobial agents and modern neurosurgical instruments and techniques.I report the case of a 64-yearold woman,affected by a right frontobasal brain abscess,compressing the homolateral frontal horn of lateral ventricle,with a second mass partially occupying the right orbital cavity.She presented also with inflammatory sinusopathy involving the right maxillary,ethmoid and frontal sinuses.After 14 d of clinical observation and antimicrobial therapy,the patient received a computed tomography scan,which showed growth of the cerebral mass,with a ring of peripheral contrast enhancement and surrounding edema.She promptly underwent neurosurgical treatment and recovered well,except for the sight in her right eye,which remained compromised,as before the operation.This is believed to be the first case of cryptogenic cerebral abscess caused by Raoultella ornithinolityca isolated from the brain,with more than 1-year follow-up.

Perioperative Nursing of a Case of Right Temporal Lobe Brain Abscess Ruptured into the Ventricle

Objective: To explore the perioperative nursing method of brain abscess breaking into the ventricle. Methods: By reviewing the clinical data of 1 case of right temporal lobe brain abscess into the ventricle, the effective nursing methods were summarized. Results: The patient’s condition was advanced quickly, and the diagnosis was treated in time to avoid brain hernia, but the treatment was difficult because of the critical condition. Conclusion: Brain abscess is a very serious intracranial infectious disease. It is of great significance to observe the changes in patients’ condition and take effective nursing measures.

Blood-brain barrier and cerebral blood flow: Age differences in hemorrhagic stroke

Neonatal stroke is similar to the stroke that occurs in adults and produces a significant morbidity and long-term neurologic and cognitive deficits.There are important differences in the factors,clinical events and outcomes associated with the stroke in infants and adults.However,mechanisms underlying age differences in the stroke development remain largely unknown.Therefore,treatment guidelines for neonatal stroke must extrapolate from the adult data that is often not suitable for children.The new information about differences between neonatal and adult stroke is essential for identification of significant areas for future treatment and effective prevention of neonatal stroke.Here,we studied the development of stress-induced hemorrhagic stroke and possible mechanisms underlying these processes in newborn and adult rats.Using histological methods and magnetic resonance imaging,we found age differences in the type of intracranial hemorrhages.Newborn rats demonstrated small superficial bleedings in the cortex while adult rats had more severe deep bleedings in the cerebellum.Using Doppler optical coherent tomography,we found higher stress-reactivity of the sagittal sinus to deleterious effects of stress in newborn vs.adult rats suggesting that the cerebral veins are more vulnerable to negative stress factors in neonatal vs.adult brain in rats.However,adult but not newborn rats demonstrated the stroke-induced breakdown of blood brain barrier(BBB)permeability.The one of possible mechanisms underlying the higher resistance to stress-related stroke injures of cerebral vessels in newborn rats compared with adult animals is the greater expression of two main tight junction proteins of BBB(occludin and claudin-5)in neonatal vs.mature brain in rats.

Abscess in the Splenium of the Corpus Callosum Treated with Direct Drainage via an Occipital Interhemispheric Approach

Lesions in the corpus callosum typically represent malignant tumors such as glioblastoma or lymphoma, because of its compact structure comprising tightly packed white-matter tracts. Brain abscess is rarely seen in the corpus callosum. To the best of our knowledge, solitary bacterial abscess confined to the splenium of the corpus callosum has not been reported previously. We report the case of a 72-year-old woman with rapidly progressing disturbance of consciousness following 1 week of antibiotic treatment for bacterial meningitis. Magnetic resonance imaging demonstrated a ring-enhancing round mass located in the splenium of the corpus callosum on gadolinium-enhanced T1-weighted imaging, also showing a bright signal on diffusion-weighted imaging. The patient underwent occipital craniotomy and direct drainage of the lesion in the splenium through the interhemispheric fissure and achieved complete recovery. Brain abscess should be considered among the differential diagnoses for lesions in the splenium of the corpus callosum. An occipital interhemispheric approach to the splenium might be an important option in cases of brain abscess.

Neonatal Brain Abscess:Case Report of 12 Cases and Literature Review

Objective:To investigate the etiological characteristics,clinical manifestations,and early identification methods of neonatal brain abscess.Methods:The baseline characteristics,clinical manifestations,and laboratory results of 12 neonatal brain abscess cases were retrospectively analyzed.Results:The clinical manifestations were fever,convulsion,and lethargy.A small number of them had respiratory and circulatory failure.The diagnosis made was based on imaging examination.All 12 cases were confirmed by cranial enhanced computed tomography(CT)or magnetic resonance imaging(MRI).Blood cultures of 9 cases were positive,with Escherichia coli in 6 cases,β-hemolytic Streptococcus in 1 case,methicillin-resistant Staphylococcus aureus in 1 case,and Enterococcus faecium in 1 case.However,only 3 of them had positive cerebrospinal fluid(CSF)cultures.All the 12 neonates were treated with antibiotic therapy upon admission,with only 3 cases treated with surgery.Among them,4 recovered and were discharged,while the remaining 8 discontinued their therapy.Conclusion:Escherichia coli is the most common pathogen of neonatal brain abscess in our study.The clinical manifestations of neonatal brain abscess are atypical,and the prognosis is poor.Respiratory and circulatory failure in children with intracranial infection may indicate the presence of brain abscess.For children with suspected brain abscess,cranial enhanced CT or MRI should be performed as soon as possible to make an early diagnosis.The prevention of brain abscess should be prioritized;neonates with sepsis or meningitis should receive prompt and strong antibiotic therapy in an effort to prevent the development of brain abscess.

皮疽诺卡菌致多发脑脓肿1例并文献复习

目的 分析皮疽诺卡菌累及中枢神经系统的临床特征、诊断及治疗,以期提高对该疾病的认识,精准抗感染治疗。方法 报告清华大学附属北京清华长庚医院感染性疾病科收治的1 例皮疽诺卡菌感染致多发脑脓肿的病例,并以“Nocardiafarcinica”为关键词检索PubMed 1967年1月1日-2022年9月18日的英文文献共433篇,分别以“皮疽奴卡菌”“ 皮疽诺卡菌”“鼻疽奴卡菌”“ 鼻疽诺卡菌”为关键词在万方数据库、维普数据库检索 1999 年 10 月 1 日-2022 年 9 月 18 日的中文文献,共153 篇,收集并分析总结70 例皮疽诺卡菌中枢神经系统感染的病例资料。结果 该院这例患者以“头痛伴意识障碍”入院,入院后脑脊液宏基因组二代测序(mNGS)提示为皮疽诺卡菌,以复方磺胺甲唑为主联合美罗培南、莫西沙星、阿米卡星为治疗方案,治疗1 个月病灶吸收,院外口服复方磺胺甲唑、莫西沙星,总疗程为1 年。文献70 例皮疽诺卡菌中枢神经系统感染患者男性51 例,占72.8%,平均年龄(58.6±15.3)岁,57.1% 患者有糖皮质激素使用史,57.1% 患者同时合并其他脏器播散,80.0%(56 例)的患者通过传统细菌培养明确病原学诊断,其余通过聚合酶链反应或mNGS 诊断。抗感染用药以复方磺胺甲唑为主(85.7%),死亡率24.2%。结论 皮疽诺卡菌中枢神经系统感染,以发热、肢体活动障碍、头痛为主要临床表现,除中枢神经系统受累外,易全身播散,且有较高的死亡率。该病临床表现缺乏特异性,诊断及治疗相对困难,病死率较高,包括mNGS 在内的多种检测手段可协助尽早明确病原学诊断。

艾迪注射液联合常规化疗对肺癌脑转移患者的临床疗效

目的观察艾迪注射液联合化疗对肺癌脑转移患者认知障碍的缓解情况。方法回顾性分析2018年6月至2020年6月在浙江省丽水市人民医院就诊的80例肺癌脑转移患者的临床资料,按照不同治疗方法分为常规化疗组和艾迪组,常规化疗组患者采用顺铂联合多西他赛的化疗方案,艾迪组在常规化疗组基础上予以艾迪注射液。观察2组患者的近期疗效、认知功能以及毒副作用,评价联合艾迪注射液治疗的有效性和安全性。结果常规化疗组患者近期有效率50%,艾迪组患者近期有效率73%,2组差异有统计学意义(χ^(2)=4.266,P=0.039)。治疗开始前,常规化疗组和艾迪组患者的蒙特利尔认知评估量表(MoCA)评分和简易智能量表(MMSE)评分差异无统计学意义。治疗后2周,与常规化疗组比较,艾迪组患者的MoCA评分和MMSE评分均增加,差异具有统计学意义(t=-3.462、-2.507,P=0.001、0.047);治疗后2周艾迪组患者的Karnofsky评分和生活质量量表(QOL)评分升高,差异具有统计学意义(t=-4.634、-4.050,P<0.01)。与常规化疗组比较,艾迪组患者骨髓抑制和眩晕情况减轻,差异具有统计学意义(χ^(2)=4.126、4.050,P=0.042、0.044),恶心呕吐等胃肠道反应和脱发情况差异无统计学意义(P>0.05)。80例患者均因本病死亡。常规化疗组患者平均生存期为(15±3)个月,艾迪组患者的中位生存期为(18±4)个月,2组差异无统计学意义(χ^(2)=17.752,P<0.01)。结论艾迪注射液联合常规化疗方案治疗肺癌脑转移患者可提升近期疗效,缓解认知障碍,减轻化疗的毒副作用,但对于患者的生存期无明显影响。

洛菲氏不动杆菌感染性多发鼻窦炎导致鼻窦沟通脑脓肿1例

脑脓肿多因邻近组织感染扩散导致。洛菲氏不动杆菌是一种需氧的革兰氏阴性杆菌,定植于口咽部、皮肤、会阴部等,为一种机会性致病菌,在人体免疫力低下时引起免疫系统受损并导致感染。洛菲氏不动杆菌导致鼻窦沟通脑脓肿临床罕见。本文报道1例洛菲氏不动杆菌感染性多发鼻窦炎继发导致鼻窦沟通脑脓肿,24岁男性,因突发头痛半个月入院,入院血常规、血清CRP和降钙素原未见异常;脑脊液常规、生化、细菌及真菌培养未见异常;头颅CT、MRI检查考虑左侧额叶多发脓肿,左侧上颌窦和右侧蝶窦囊肿;脑脊液病原微生物检测DNA、RNA检测显示洛菲不动杆菌。给予万古霉素、美罗培南、奥硝唑治疗1周后,复查头颅CT示颅内低密度灶减少。完善术前准备后,行经鼻内镜下左侧鼻窦病损切除+左侧上颌窦、筛窦、额窦切开术。术后1个月复查头部CT及增强MRI示左额叶多发脑脓肿吸收、减少。术后3个月电话随访头痛明显好转。这提示临床上怀疑脑脓肿时,可行CT及MRI检查,以明确诊断,并经验性给予抗生素治疗。当培养不能发现病原菌时,可行基因检测增加检出率。

脑脓肿诊疗现状及研究进展

脑脓肿(BA)是一种中枢神经系统化脓性感染性疾病,可在脑实质中形成一个包膜包裹的脓腔。BA进展快、预后差的特点使其临床诊疗具有巨大挑战性。对于BA的诊疗形成了一定的共识,同时无论是新致病菌的发现、新诊断技术的推出、该疾病预后的新发现,还是仍在探究的许多争议,如糖皮质激素的使用及其治疗效果的影响、手术方式的选择等均代表着该疾病研究领域的蓬勃发展。本文针对BA的诊疗现状及其研究进展进行综述,以期为BA的临床诊疗提供参考。

大鼠骨髓间充质干细胞的分离培养及CM-Dil标记的脑内示踪

目的建立大鼠骨髓间充质干细胞(BMSCs)的分离和培养方法 ,并探讨采用氯甲基苯甲酰胺(CM-Dil)对BMSCs进行体外标记和体内示踪的可行性。方法全骨髓贴壁法分离获取BMSCs,收集第3代细胞,流式细胞术检测CD34、CD44和CD29的表达率。加入CM-Dil对BMSCs进行体外标记,荧光倒置显微镜下观察24h、21d和30d时的标记情况,通过描绘生长曲线明确CM-Dil对体外培养BMSCs生长特性的影响。制作局灶性脑缺血大鼠模型,将CM-Dil标记的BMSCs立体定向移植至大脑纹状体区,于移植后7、14、21d取脑组织制备冰冻切片,荧光显微镜下观察标记细胞在脑内的存活及分布情况。结果 BMSCs贴壁培养至第3代后呈成纤维细胞样,形态均一、排列有序,CD34、CD44和CD29表达率分别为1.71%、80.32%和84.89%。体外CM-Dil标记24h的BMSCs发出红色荧光,标记率为100%;21d后,经传代培养的BMSCs荧光强度与24h时点相近,但30d后荧光有所淬灭。标记后细胞的生长、增殖特性未受影响,形态无改变。脑组织冰冻切片发现移植的BMSCs在7、14、21d时主要位于针道附近,并向周围扩散,数量逐渐减少,呈椭圆形或不规则形。结论通过贴壁培养可以从大鼠骨髓中分离培养出较纯的BMSCs。CM-Dil染色简单、有效、无细胞毒性,体外标记BMSCs的最长时限为21d,可作为BMSCs脑内定向移植的体内示踪方法 。