Cerebral fat embolism following autologous fat injection in facial reconstruction:A case report

BACKGROUND Autologous fat injection in facial reconstruction is a common cosmetic surgery.Although cerebral fat embolism(CFE)as a complication is rare,it carries serious health risks.CASE SUMMARY We present a case of a 29-year-old female patient who developed acute CFE following facial fat filling surgery.After the surgery,the patient experienced symptoms including headache,nausea,vomiting,and difficulty breathing,which was followed by neurological symptoms such as slurred speech and left-sided weakness.Comprehensive physical examination and auxiliary investigations,including blood tests,head and neck computed tomography angiography,and cranial magnetic resonance diffusion-weighted imaging,were performed upon admission.The clinical diagnosis was acute cerebral embolism following facial fat filling surgery.Treatment included measures to improve cerebral circulation,dehydration for intracranial pressure reduction,nutritional support,and rehabilitation therapy for left limb function.The patient showed a significant improvement in symptoms after 2 weeks of treatment.She recovered left limb muscle strength to grade 5,had clear speech,and experienced complete relief of headache.CONCLUSION Our case highlights the potential occurrence of severe complications in patients undergoing fat injection in facial reconstruction.To prevent these complications,plastic surgeons should enhance their professional knowledge and skills.

Left ventricular thrombosis caused cerebral embolism during venoarterial extracorporeal membrane oxygenation support: A case report

BACKGROUND Venoarterial(VA)extracorporeal membrane oxygenation(ECMO),an effective short-term circulatory support method for refractory cardiogenic shock,is widely applied.However,retrospective analyses have shown that VA-ECMO-assisted cases were associated with a relatively high mortality rate of approximately 60%.Embolization in important organs caused by complications of left ventricular thrombosis(LVT)during VA-ECMO is also an important reason.Although the incidence of LVT during VA-ECMO is not high,the consequences of embolization are disastrous.CASE SUMMARY A 37-year-old female patient was admitted to hospital because of fever for 4 d and palpitations for 3 d.After excluding the diagnosis of coronary heart disease,we established a diagnosis of“clinically explosive myocarditis”.The patient still had unstable hemodynamics after drug treatment supported by VA-ECMO,with heparin for anticoagulation.On day 4 of ECMO support,a left ventricular thro-mbus attached to the papillary muscle root of the mitral valve was found by transthoracic echocardiography.Left ventricular decompression was performed and ECMO was successfully removed,but the patient eventually died of multiple cerebral embolism.CONCLUSION LVT with high mobility during VA-ECMO may cause embolism in important organs.Therefore,a"wait and see"strategy should be avoided.

Revisiting cerebral endothelial cells in Alzheimer’s disease

Alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory functions.In only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the cases.The amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

Roles of N-cadherin in cerebral cortical development:cooperation with membrane trafficking and actin cytoskeletal regulation

Cell adhesion plays pivotal roles in the morphogenesis of multicellular organisms.Epithelial cells form several types of cell-to-cell adhesion,including zonula occludens(tight junctions),zonula adhaerens(adherens junctions),and macula adhaerens(desmosomes).Although these adhesion complexes are basically observed only in epithelial cells,cadherins,which are the major cell adhesion molecules of adherens junctions,are expressed in both epithelial and non-epithelial tissues,including neural tissues(Kawauchi,2012).The cadherin superfamily consists of more than 100 members,but classic cadherins.

Small extracellular vesicles derived from cerebral endothelial cells with elevated microRNA 27a promote ischemic stroke recovery

Axonal remodeling is a critical aspect of ischemic brain repair processes and contributes to spontaneous functional recovery.Our previous in vitro study demonstrated that exosomes/small extracellular vesicles(sEVs)isolated from cerebral endothelial cells(CEC-sEVs)of ischemic brain promote axonal growth of embryonic cortical neurons and that microRNA 27a(miR-27a)is an elevated miRNA in ischemic CEC-sEVs.In the present study,we investigated whether normal CEC-sEVs engineered to enrich their levels of miR-27a(27a-sEVs)further enhance axonal growth and improve neurological outcomes after ischemic stroke when compared with treatment with non-engineered CEC-sEVs.27a-sEVs were isolated from the conditioned medium of healthy mouse CECs transfected with a lentiviral miR-27a expression vector.Small EVs isolated from CECs transfected with a scramble vector(Scra-sEVs)were used as a control.Adult male mice were subjected to permanent middle cerebral artery occlusion and then were randomly treated with 27a-sEVs or Scra-sEVs.An array of behavior assays was used to measure neurological function.Compared with treatment of ischemic stroke with Scra-sEVs,treatment with 27a-sEVs significantly augmented axons and spines in the peri-infarct zone and in the corticospinal tract of the spinal grey matter of the denervated side,and significantly improved neurological outcomes.In vitro studies demonstrated that CEC-sEVs carrying reduced miR-27a abolished 27a-sEV-augmented axonal growth.Ultrastructural analysis revealed that 27a-sEVs systemically administered preferentially localized to the pre-synaptic active zone,while quantitative reverse transcription-polymerase chain reaction and Western Blot analysis showed elevated miR-27a,and reduced axonal inhibitory proteins Semaphorin 6A and Ras Homolog Family Member A in the peri-infarct zone.Blockage of the Clathrin-dependent endocytosis pathway substantially reduced neuronal internalization of 27a-sEVs.Our data provide evidence that 27a-sEVs have a therapeutic effect on stroke recovery by promoting axonal remodeling and improving neurological outcomes.Our findings also suggest that suppression of axonal inhibitory proteins such as Semaphorin 6A may contribute to the beneficial effect of 27a-sEVs on axonal remodeling.

Mimicking aneurysm in a patient with chronic occlusion of the left middle cerebral artery

The chronic occlusion of intracranial arteries generally has no or mild clinical symptoms,and the clinical symptoms of acute cerebral artery occlusion are mostly manifested as severe cerebral infarction symptoms,which often make early diagnosis difficult,thus losing the best treatment opportunity.Once cerebral infarction occurs,the consequences are difficult to recover.This is also an important reason for the high misdiagnosis rate and mortality of this disease.In this paper,the characteristics of the disease were analyzed to provide clinical reference.

Human-induced pluripotent stem cell-derived neural stem cell exosomes improve blood-brain barrier function after intracerebral hemorrhage by activating astrocytes via PI3K/AKT/MCP-1 axis

Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor prognosis.Human-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)have shown potential for brain injury repair in central nervous system diseases.In this study,we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying mechanism.Our results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits,enhanced blood-brain barrier integrity,and reduced leukocyte infiltration in a mouse model of intracerebral hemorrhage.Additionally,hiPSC-NSC-Exos decreased immune cell infiltration,activated astrocytes,and decreased the secretion of inflammatory cytokines like monocyte chemoattractant protein-1,macrophage inflammatory protein-1α,and tumor necrosis factor-αpost-intracerebral hemorrhage,thereby improving the inflammatory microenvironment.RNA sequencing indicated that hiPSC-NSC-Exo activated the PI3K/AKT signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion,thereby improving blood-brain barrier integrity.Treatment with the PI3K/AKT inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these effects.In summary,our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity,in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3K/AKT signaling pathway in astrocytes.

Pulmonary embolism after shoulder surgery:Is it a real threat?

Pulmonary embolism(PE)is a rare but devastating complication of shoulder surgery.Apart from increased morbidity and mortality rates,it may significantly impair postoperative recovery and functional outcome.Its frequency accounts for up to 5.7%of all shoulder surgery procedures with a higher occurrence in women and patients older than 70 years.It is most commonly associated with thrombophilia,diabetes mellitus,obesity,smoking,hypertension,and a history of malignancy.PE usually occurs secondary to upper or lower-extremity deep vein thrombosis(DVT).However,in rare cases,the source of the thrombi cannot be determined.Prophylaxis for PE following shoulder surgery remains a topic of debate,and the standard of care does not routinely require prophylactic medication for DVT prophylaxis.Early ambulation and elastic stockings are important preventative measures for DVT of the lower extremity and medical agents such as aspirin,low-molecular-weight heparin,and vitamin K antagonists are indicated for high-risk patients,long-lasting operations,or concomitant severe acute respiratory syndrome coronavirus 2 infection.The most common symptoms of PE include chest pain and shortness of breath,but PE can also be asymptomatic in patients with intrinsic tolerance of hypoxia.Patients with DVT may also present with swelling and pain of the respective extremity.The treatment of PE includes inpatient or outpatient anticoagulant therapy if the patient is hemodynamically unstable or stable,respectively.Hemodynamic instability may require transfer to the intensive care unit,and cardiovascular arrest can be implicated in fatal events.An important issue for patients with PE in the postoperative period after shoulder surgery is residual stiffness due to a delay in rehabilitation and a prolonged hospital stay.Early physiotherapy and range-of-motion exercises do not adversely affect the prognosis of PE and are highly recommended to preserve shoulder mobility and function.

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion injury.Autophagy occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains unclear.In this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion injury.We found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced autophagy.Furthermore,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating autophagy.Blocking autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion injury.Findings from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury

The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically reviewed.Here,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion injury.We further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple mechanisms.Inhibition of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

Cerebral and pulmonary embolisms after transcatheter arterial chemoembolization for hepatocellular carcinoma

A cerebral lipiodol embolism is an extremely rare complication of transcatheter arterial chemoembolization for hepatocellular carcinoma. We present a case of cerebral lipiodol embolism that occurred after the third arterial chemoembolization, report the clinical and radiological findings, and review the medical literature.

Pulmonary and cerebral lipiodol embolism after transcatheter arterial hemoembolization in hepatocellular carcinoma

Pulmonary and cerebral lipiodol embolism after transcatheter arterial chemoembolization (TACE) of hepatocellular carcinoma is rare. To our knowledge, only 7 cases have been reported in the literature. We present a case of pulmonary and cerebral lipiodol embolism, and analyzed retrospectively the imaging and clinical data of the patient and conclude the most probable mechanism of pulmonary and cerebral lipiodol embolism, which is different from that of the cases reported previously.

Cerebral lipiodol embolism related to a vascular lake during chemoembolization in hepatocellular carcinoma:A case report and review of the literature

A male patient underwent conventional transcatheter chemoembolization for advanced recurrent hepatocellular carcinoma(HCC). Even after the injection of 7 m L of lipiodol followed by gelatin sponge particles, the flow of feeding arteries did not slow down. A repeat angiography revealed a newly developed vascular lake draining into systemic veins; however, embolization was continued without taking noticing of the vascular lake. The patient's level of consciousness deteriorated immediately after the procedure, and non-contrast computed tomography revealed pulmonary and cerebral lipiodol embolisms. The patient's level of consciousness gradually improved after 8 wk in intensive care. In this case, a vascular lake emerged during chemoembolization and drained into systemic veins, offering a pathway carrying lipiodol to pulmonary vessels, the most likely cause of this serious complication. We should be aware that vascular lakes in HCC may drain into systemic veins and can cause intratumoral arteriovenous shunts.

Cerebral lipiodol embolism following transcatheter arterial chemoembolization for hepatocellular carcinoma

Cerebral lipiodol embolism (CLE) is an extremely rare complication of transcatheter arterial chemoembolization for hepatocellular carcinoma (HCC). The authors present a case of CLE that occurred after the second hepatic arterial chemoembolization for HCC, and attempt to introduce several plausible mechanisms of CLE, after reporting the clinical and radiological findings and reviewing the medical literature.

Cerebral lipiodol embolism after transarterial chemoembolization for hepatic carcinoma:A case report

We report a case of cerebral lipiodol embolism(CLE) after transarterial chemoembolization(TACE) for unresectable hepatic carcinoma(HCC).A 54-year-old man with unresectable HCC underwent TACE via the right hepatic artery and right inferior phrenic artery using a mixture of 40 mg pirarubicin and 30 mL lipiodol.His level of consciousness deteriorated after TACE,and non-contrast computed tomography revealed a CLE.The cerebral conditions improved after supportive therapy.The complication might have been due to hepatic arterio-pulmonary vein shunt caused by direct invasion of the tumor.Even though CLE is an uncommon complication of TACE,we should be aware of these rare complications in patients with high risk factors.

Anticoagulant treatment for pulmonary embolism in patient with cerebral hemorrhage secondary to mechanical thrombectomy: A case report

BACKGROUND Cerebral hemorrhage secondary to cerebral embolism after mechanical thrombectomy is characterized by high morbidity,disability and mortality.If the patient also has severe pulmonary embolism(PE)at the same time,the treatment becomes more complex.This report describes the treatment strategy for a patient with PE and cerebral hemorrhage secondary to cerebral embolism after mechanical thrombectomy.CASE SUMMARY A 70-year-old woman presented to our emergency department with right-sided hemiplegia and mixed aphasia of 2.5 h duration.She was diagnosed with left cerebral embolism,left internal carotid artery occlusion,PE and left calf intramuscular vein thrombosis.Following mechanical thrombectomy,brain magnetic resonance imaging showed cerebral infarction with basal ganglia hemorrhage.We observed changes in cerebral hemorrhage on serial monitoring of brain computed tomography and adjusted the dose of anticoagulant drugs.After 3 wk of treatment,the patient’s neurological and respiratory symptoms significantly improved,and a favorable prognosis was obtained.CONCLUSION Anticoagulation could be a potential option for PE accompanied by hemorrhagic transformation of an ischemic infarct.

Cerebral Fat Embolism Syndrome from Penetrating Trauma: A Rare Cause-and-Effect

A 42 year-old male sustained an accidental rifle gunshot wound to his left foot, resulting in fracture deformities of the calcaneus, navicular, cuneiform, 1st and 2nd metatarsal bases, and talus. As he was transported to our trauma center, he developed progressive encephalopathy. Urgent external fixator placement under general anesthesia was postponed due to his encephalopathy of unknown etiology. Brain magnetic resonance imaging demonstrated a “starfield” pattern of infarcts, consistent with cerebral fat embolism syndrome. Subsequently, he underwent uneventful general anesthesia. The patient was managed supportively and continued to have persistent neurologic dysfunction two months after injury.

Cerebral air embolism complicating transbronchial lung biopsy: A case report

BACKGROUND In this case report we describe an extremely rare case of cerebral air embolism following transbronchial lung biopsy(TBLB).Only a few cases of this rare complication were described previously.Every bronchologist should recognize this severe adverse event.Prompt recognition of this complication is mandatory in order to initiate supportive measures and consider hyperbaric oxygen therapy.CASE SUMMARY In this case report we describe an extremely rare case of cerebral air embolism following TBLB.Only a few cases of this rare complication were described previously.Our patient had an incidental finding of lung tumour and pulmonary emphysema.Cerebral air embolism developed during bronchoscopy procedure,immediately after the third trans-bronchial lung biopsy sample and caused cerebral ischaemia of the right hemisphere and severe left-sided hemiplegia.Despite timely initiation of hyperbaric oxygen therapy hemiplegia didn´t resolve and the patient died several weeks later.Cerebral air embolism is an extremely rare complication of TBLB.This condition should be considered in case the patient remains unresponsive or presents with acute neurological symptoms in the postintervention period since early recognition,diagnosis and hyperbaric oxygen therapy initiation are key factors determining the patient´s outcome.CONCLUSION Within this report,we conclude that air/gas embolism is an extremely rare complication after TBLB,which should be considered in case the patient remains unresponsive or presents with acute neurological symptoms in the postintervention period after bronchoscopy.The current gold standard for diagnosis is computed tomography scan of the head.After recognition of this complication we suggest immediate hyperbaric oxygen therapy,if available.

Blood-brain barrier pathology in cerebral small vessel disease

Cerebral small vessel disease is a neurological disease that affects the brain microvasculature and which is commonly observed among the elderly.Although at first it was considered innocuous,small vessel disease is nowadays regarded as one of the major vascular causes of dementia.Radiological signs of small vessel disease include small subcortical infarcts,white matter magnetic resonance imaging hyperintensities,lacunes,enlarged perivascular spaces,cerebral microbleeds,and brain atrophy;however,great heterogeneity in clinical symptoms is observed in small vessel disease patients.The pathophysiology of these lesions has been linked to multiple processes,such as hypoperfusion,defective cerebrovascular reactivity,and blood-brain barrier dysfunction.Notably,studies on small vessel disease suggest that blood-brain barrier dysfunction is among the earliest mechanisms in small vessel disease and might contribute to the development of the hallmarks of small vessel disease.Therefore,the purpose of this review is to provide a new foundation in the study of small vessel disease pathology.First,we discuss the main structural domains and functions of the blood-brain barrier.Secondly,we review the most recent evidence on blood-brain barrier dysfunction linked to small vessel disease.Finally,we conclude with a discussion on future perspectives and propose potential treatment targets and interventions.