Preoperative peripheral inflammatory markers are predictors of postoperative central diabetes insipidus in craniopharyngioma patients: a retrospective study.

BACKGROUND: Postoperative central diabetes insipidus (CDI) is commonly observed in craniopharyngioma (CP) patients, and the inflammatory response plays an important role in CPs. We aimed to evaluate the predictive value of preoperative peripheral inflammatory markers and their combinations regarding CDI occurrence in CPs. METHODS: The clinical data including preoperative peripheral inflammatory markers of 208 CP patients who underwent surgical treatment were retrospectively collected and analyzed. The preoperative peripheral white blood cells (WBC), neutrophils, lymphocytes, monocytes, platelet (PLT), neutrophil-to-lymphocyte ratio (NLR), derived-NLR (dNLR), monocyte-to-lymphocyte ratio (MLR) and PLT-to-lymphocyte ratio (PLR) were assessed in total 208 CP patients and different age and surgical approach CP patient subgroups. Their predictive values were evaluated by the receiver operator characteristic curve analysis. RESULTS: Preoperative peripheral WBC, neutrophils, NLR, dNLR, MLR, and PLR were positively correlated and lymphocyte was negatively associated with postoperative CDI occurrence in CP patients, especially when WBC ≥ 6.66 × 109/L or lymphocyte ≤ 1.86 × 109/L. Meanwhile, multiple logistic regression analysis showed that WBC > 6.39 × 109/L in the > 18 yrs age patients, WBC > 6.88 × 109/L or lymphocytes ≤ 1.85 × 109/L in the transcranial approach patients were closely associated with the elevated incidence of postoperative CDI. Furthermore, the area under the curve obtained from the receiver operator characteristic curve analysis showed that the best predictors of inflammatory markers were the NLR in total CP patients, the MLR in the ≤ 18 yrs age group and the transsphenoidal group, the NLR in the > 18 yrs age group and the dNLR in the transcranial group. Notably, the combination index NLR + dNLR demonstrated the most valuable predictor in all groups. CONCLUSIONS: Preoperative peripheral inflammatory markers, especially WBC, lymphocytes and NLR + dNLR, are promising predictors of postoperative CDI in CPs.

Trends and hotspots in research of traumatic brain injury from 2000 to 2022: A bibliometric study.

Traumatic brain injury (TBI) is a major health concern globally, which is characterized by high morbidity and mortality rates. Since the 21st century, TBI has received increasing attention and the number of publications is growing rapidly. This study aimed to characterize the volume and quality of scholarly output on TBI and identify the most impactful literature, research trends, and hotspots from the year 2000-2022. We searched publications on TBI through the Web of Science Core Collection-Science Citation Index Expanded database which were published from 2000 to 2022. Basic information of each paper, including publication year, countries, authors, affiliations, journal, fundings, subject areas, and keywords were collected for further analysis by using Microsoft Excel, VOSviewer, and CiteSpace software. A total of 47231 TBI-related publications were identified through database retrieval. The annual number of publications on TBI has increased steadily over the past twenty years and the number in the year 2022 is sevenfold higher than that in 2000. The United States of America (USA) was the leading country in both numbers of publications and citations, which is consistent with the finding that it had the most funding agencies. Menon DK was the author with the highest influence and the University of California System was the most productive affiliation. Moreover, keywords analysis suggested that the research topics can be mainly divided into six categories: management, rehabilitation, mechanisms, concussion, neuroimaging, and neuroendocrine. This study visualized the trends and focuses of scientific research related to TBI, both quantitatively and qualitatively. The USA had a relatively high academic impact owing to its productive experts and institutions in this field. Neuroinflammation, machine learning, tranexamic acid, and extracellular vesicles are currently hot topics in the field of TBI.

Axial Convex-Shaped Hematoma was Associated with Poor Curative Effect of Surgical Treatment for Traumatic Posterior Fossa Epidural Hematoma in Children.

BACKGROUND: Posterior fossa epidural hematoma (PFEDH) is rare which accounts for just 4-12.9% of all EDH cases. Since its frequently subtle and nonspecific clinical presentation, CT scan has great importance for early diagnosis and treatment of PFEDH. However, indications for surgery depending on the findings of CT image are still controversial. METHODS: We retrospectively analyzed 40 pediatric cases of PFEDH. Their baseline characteristic, clinical presentation, imaging findings and outcomes were collected and analyzed. The ellipsoid volume equation X × Y × Z/2 was used to measure the hematoma volume. The Glasgow Outcome Scale (GOS) was used to assess the neurologic functional outcome. RESULTS: A total of 40 pediatric PFEH patients were included with 8 patients having poor outcome and 32 patients having a relatively good prognosis. GCS score showed a significant difference between good and poor outcome groups (p < 0.001). Y value on CT image was significantly bigger in poor outcome group than good outcome group (p < 0.01). Similar results were got in X/Z value (p < 0.05) and Y/Z value (p < 0.01) which reflected the shape of hematoma. A predictive model with Y + X/Z showed the largest area under the ROC curve with a sensitivity of 75.0% and specificity of 93.7%. CONCLUSIONS: GCS score at admission was closely related to the prognosis of the pediatric patients with PFEDH. The morphometry of PFEDH has a crucial role in judging the prognosis. Axial convex-shaped hematoma was associated with poor curative effect of surgical treatment.

Spontaneous Hyperventilation Is Common in Patients with Spontaneous Cerebellar Hemorrhage, and Its Severity Is Associated with Outcome.

BACKGROUND: The spontaneous hyperventilation (SHV) accompanying spontaneous cerebellar hemorrhage has yet to attract a sufficient amount of attention. This study aimed to analyze the incidence of SHV in spontaneous cerebellar hemorrhage patients and its risk factors as well as its association with the outcome. METHODS: We retrospectively reviewed the medical records of all spontaneous cerebellar hemorrhage patients who underwent surgical treatment at Tongji Hospital from July 2018 to December 2020. Arterial blood gas (ABG) test results and clinical characteristics, including demographics, comorbidities, imaging features, laboratory tests, and therapy choices, were collected. The Glasgow Outcome Scale was used to assess the outcome at two weeks and six months after admission. RESULTS: A total of 147 patients were included, and of these patients 44.9% had spontaneous hyperventilation. Hypertension (OR, 3.175; CI, 1.332-7.569), usage of sedation drugs (OR, 3.693; CI, 1.0563-8.724), and hypernatremia (OR, 2.803; CI, 1.070-7.340) seemed to positively correlate to SHV occurrence. Hematoma removal had an inverse association with SHV (OR, 0.176; CI, 0.068-0.460). Patients with poor and good outcomes had significant differences in pH, PaCO2, and HCO3- values, and the severity of SHV was associated with the PaCO2 level. CONCLUSIONS: Spontaneous hyperventilation is common in patients with spontaneous cerebellar hemorrhage, and its severity is associated with the outcome.

PDCD10 promotes the aggressive behaviors of pituitary adenomas by up-regulating CXCR2 and activating downstream AKT/ERK signaling.

As the second most common primary intracranial neoplasms, about 40% of pituitary adenomas (PAs) exhibit aggressive behaviors and resulting in poor patient prognosis. The molecular mechanisms underlying the aggressive behaviors of PAs are not yet fully understood. Biochemical studies have reported that programmed cell death 10 (PDCD10) is a component of the striatin-interacting phosphatase and kinase (STRIPAK) complex and plays a dual role in cancers in a tissue- or disease-specific manner. In the present study, we report for the first time that the role of PDCD10 in PAs. Cell proliferation, migration and invasion were either enhanced by overexpressing or inhibited by silencing PDCD10 in PA cells. Moreover, PDCD10 significantly promoted epithelial-mesenchymal transition (EMT) of pituitary adenoma cells. Mechanistically, we showed that the expression of CXCR2, together with phosphorylation levels of AKT and ERK1/2 were regulated by PDCD10. Activation of CXCR2 inversed inactivation of AKT/ERK signal pathways and the tumor-suppressive effects induced by PDCD10 silencing. Finally, the pro-oncogenic effect of PDCD10 was confirmed by in vivo tumor grafting. Taken together, we demonstrate for the first time that PDCD10 can induce aggressive behaviors of PAs by promoting cellular proliferation, migration, invasion and EMT through CXCR2-AKT/ERK signaling axis.

Early Enteral Nutrition Can Reduce Incidence of Postoperative Hydrocephalus in Patients with Severe Hypertensive Intracerebral Hemorrhage.

BACKGROUND Hydrocephalus secondary to hypertensive intracerebral hemorrhage (HICH) dramatically affects the prognosis. Early enteral nutrition (EN) is beneficial to severe HICH patients, but the impact of early EN administration on hydrocephalus remains unknown. This study aimed to explore the predictors for hydrocephalus occurrence after HICH, with special focus on the effect of early EN application. MATERIAL AND METHODS We retrospectively analyzed 146 patients with severe HICH who underwent microsurgery between January 2014 and October 2019 in our department. Patients were divided into early EN (≤48 h) and delayed EN (>48 h) group according to the time-point of EN administration. The diagnosis of hydrocephalus was confirmed by both radiological evaluation and an Evan index method. Diagnosis confirmed within 2 weeks after HICH was identified as acute hydrocephalus, otherwise, it was considered as chronic hydrocephalus. RESULTS Twenty-seven patients experienced acute hydrocephalus, while 20 patients developed chronic hydrocephalus. Low preoperative Glasgow coma scale (GCS), subarachnoid hemorrhage (SAH), intraventricular hemorrhage (IVH), delayed EN administration, high levels of postoperative white blood cell, neutrophil, neutrophil-to-lymphocyte ratio, C-reactive protein (CRP), and lactate dehydrogenase were positively related to the occurrence of chronic hydrocephalus (p<0.05), while only IVH was correlated with acute hydrocephalus occurrence (p<0.05). In addition, a multivariate analysis demonstrated that preoperative GCS, SAH, IVH, and early EN administration (p<0.05) were independent predictors for chronic hydrocephalus occurrence. CONCLUSIONS Early EN administration, SAH, IVH, and preoperative GCS were associated with the occurrence of chronic hydrocephalus in severe HICH patients. Early EN administration may inhibit the inflammatory response of brain-gut axis, which in turn reduces chronic hydrocephalus occurrence.

Levels of lncRNA GAS5 in Plasma of Patients with Severe Traumatic Brain Injury: Correlation with Systemic Inflammation and Early Outcome.

Scientific efforts continue to concentrate on elucidating the complex molecular mechanisms underlying traumatic brain injury (TBI), and recent reports suggest that epigenetic regulation including long non-coding RNA (lncRNA) is involved. The present study aimed to investigate the plasma concentration of a long non-coding RNA, named growth arrest-specific 5 (GAS5), in a group of 45 patients with severe TBI (sTBI), and to analyze the correlations of GAS5 with TBI onset, injury severity, systemic inflammation, and early outcome of the patients. It was found that plasma GAS5 levels were substantially increased in sTBI patients compared with the relative controls (p < 0.001). Further, significantly higher expression of plasma GAS5 was observed in patients with a Glasgow Coma Scale (GCS) score of less than five (p = 0.002) or unfavorable outcome at discharge (p < 0.001). Circulating GAS5 expression had a negative correlation with GCS score (r = −0.406, p = 0.006), and positive correlations with white blood cell count (r = 0.473, p = 0.001), neutrophil count (r = 0.502, p < 0.001), and neutrophil/lymphocyte ratio (NLR) (r = 0.398, p = 0.007). Univariate and multivariate logistic regression analyses revealed that GCS score (OR = 0.318, 95% CI 0.132−0.767, p = 0.011) and GAS5 (OR = 2.771, 95% CI 1.025−7.494, p = 0.045) were the two independent predictors for early outcome of patients. The receiver operating characteristic (ROC) curves showed good prognostic values of GCS score (AUC = 0.856, 95% CI: 0.719−0.943) and GAS5 expression (AUC = 0.798, 95% CI: 0.651−0.903). Importantly, the combined use of them can improve the prognostic ability of TBI with an AUC of 0.895 (95% CI: 0.767−0.966). Collectively, our study indicated that the levels of lncRNA GAS5 in circulation were elevated following severe TBI and correlated well with injury severity and inflammatory parameters. In addition, GAS5 as well as GCS scores may have the potential to predict the early outcome of TBI patients.

Hemorrhagic schwannoma of the trochlear nerve: Case report and a review of the literature.

Background: Schwannomas of the trochlear nerve with the absence of systemic neurofibromatosis are considerably uncommon, especially complicated by intra-tumoral hemorrhage. Due to the lack of typical clinical manifestations and imaging findings, a definite diagnosis of trochlear schwannomas before surgery is particularly difficult. Case presentation: We report the case of a 64-year-old female patient who presented with a unilaterally intermittent headache of 2-month duration and without a remarkable neurological deficit at admission. Imaging studies revealed a well-demarcated cystic-solid lesion with mixed signals beside the brainstem and suprasellar cisterna. The patient underwent a surgical operation with total resection of the tumor by a subtemporal surgical approach. The tumor was intraoperatively found to originate from the trochlear nerve and was pathologically confirmed as a hemorrhagic schwannoma with cystic degeneration. Conclusions: We describe this case in detail and conduct a concomitant survey of the literature, summarizing the clinical presentations, radiological features, surgical treatment, and the possible mechanisms of hemorrhage in relevance to trochlear nerve schwannoma.

Comparative Analysis of Trigeminal Neuralgia Caused by Sole Arterial and Venous Compression: Clinical Features and Surgical Outcomes From 222 Cases.

Background: Compared with trigeminal neuralgia (TN) caused by arterial neurovascular conflict (NVC), the clinical characteristics and managements for TN with venous NVC are not well-established. This study aims to comparatively summarize the clinical features and surgical outcomes of microvascular decompression (MVD) for patients with TN caused by sole arterial and venous compression, with a particular focus on the morphological features of posterior cranial fossa (PCF). Methods: A total of 222 patients with TN caused by sole arterial NVC (188/84.7%) and venous NVC (34/15.3%) underwent MVD in our department from January 2014 to December 2018. The patient data were analyzed retrospectively. Particularly, we focused on the potential impact of PCF on surgical outcomes. Results: Compared with arterial NVC, V3 branch of the trigeminal nerve was more frequently involved in venous NVC (p = 0.009). The most common compression site was root entry zone for arterial NVC (68.6%) and midcisternal segment for venous NVC (76.5%) (p < 0.001). No serious post-operative complication was observed in the two groups. Both short- and long-term outcomes were relatively worse in venous NVC cases compared with arterial NVC cases (p = 0.001 and p = 0.030, respectively); and a dominantly higher rate of delayed cure was demonstrated in venous NVC cases (p < 0.001). TN patients with venous NVC revealed a more flat-shaped PCF than those with arterial NVC. Moreover, flat-shaped PCF morphometry was negatively correlated with surgical outcomes of TN patients with arterial NVC, but not with those of venous NVC cases. Conclusions: MVD is an effective and safe treatment for patients with TN caused by either arterial or venous NVC. Patients with a more flat-shaped PCF might be vulnerable to venous compression. Our study demonstrated that PCF morphometry only affected the surgical outcomes of patients with TN caused by arterial NVC, but not the outcomes of those with venous NVC.

Interferon regulatory factor transcript levels correlate with clinical outcomes in human glioma.

Members of the interferon regulatory factor (IRF) gene family are crucial regulators of type I interferon signaling, which may play a role in the resistance of glioma to immune checkpoint blockade. However, the expression profiles, potential functions, and clinical significance of IRF family members remain largely unknown. Here, we examined IRF transcript levels and clinicopathological data from glioma patients using several bioinformatic databases, including ONCOMINE, GEPIA, TCGA, and cBioPortal. We found that IRF1, IRF2, IRF5, IRF8 and IRF9 were significantly upregulated in glioma compared to normal brain tissue. Higher IRF1, IRF2, IRF3, IRF4, IRF5, IRF7, IRF8 and IRF9 mRNA levels correlated with more advanced tumor grades and poorer outcomes. Moreover, although IRFs mutation rates were low (ranging from 0.5% to 2.3%) in glioma patients, genetic alterations in IRFs were associated with more favorable patient survival. Functional analysis showed that IRFs participated in glioma pathology mainly through multiple inflammation- and immunity-related pathways. Additionally, correlations were identified between IRFs and infiltration of immune cells within glioma tissues. Collectively, these results indicate that IRF family members, including IRF1, IRF2, IRF5, IRF8 and IRF9, may serve as prognostic biomarkers and indicators of immune status in glioma patients.

Prognostic significance of ARL9 and its methylation in low-grade glioma.

This study aimed to determine the value of ARL9 expression or methylation as a biomarker for LGG survival. We investigated the expression, methylation, prognosis and immune significance of ARL9 through bioinformatics analysis. ARL9 is negatively regulated by ARL9 methylation, leading to its low expression in LGG tissues. Both low ARL9 expression and hypermethylation predicted favorable OS and PFS in LGG patients, according to the TCGA database. Cox regression demonstrated that low ARL9 expression and ARL9 hypermethylation were independent biomarkers for OS. Moreover, three other glioma databases were utilized to verify the prognostic role of ARL9 in LGG, and the similar results were reached. A meta-analysis revealed that low ARL9 expression was closely relevant to better OS. Finally, ARL9 expression exhibited a close correlation with some immune cells, especially CD8+ T cells. ARL9 could constitute a promising prognostic biomarker, and probably plays an important role in immune cell infiltration in LGG.

Preliminary Recommendations for Surgical Practice of Neurosurgery Department in the Central Epidemic Area of 2019 Coronavirus Infection.

Since December 2019, an outbreak of coronavirus disease 2019 (COVID-19) has posed significant threats to the public health and life in China. Unlike the other 6 identified coronaviruses, the SARS-Cov-2 has a high infectious rate, a long incubation period and a variety of manifestations. In the absence of effective treatments for the virus, it becomes extremely urgent to develop scientific and standardized proposals for prevention and control of virus transmission. Hereby we focused on the surgical practice in Neurosurgery Department, Tongji Hospital, Wuhan, and drafted several recommendations based on the latest relevant guidelines and our experience. These recommendations have helped us until now to achieve 'zero infection' of doctors and nurses in our department, we would like to share them with other medical staff of neurosurgery to fight 2019-nCoV infection.

Microsurgical Treatment of Epilepsy with Parenchymal Neurocysticercosis.

Parenchymal neurocysticercosis is the most common form of neurocysticercosis in the central nervous system (CNS), which mainly causes epilepsy and usually responses well to routine medications. However, there are appreciable cases of relapses refractory to medical treatment. We investigated microsurgical treatment of epilepsy with parenchymal neurocysticercosis. Nine cases of epilepsy caused by parenchymal neurocysticercosis from 2002 to 2018 were analyzed retrospectively. Cysts in 7 cases were completely removed. No case died of operation and no new dysfunction of the nervous system was observed after surgery. Among the other 9 cases, 8 cases became seizure-free or controlled by medicine according to the postoperative follow-up for 6 months to 9 years. One case was lost for follow-up. It was suggested that epilepsy with parenchymal neurocysticercosis can usually be controlled after routine medications. However, surgery is still indicated in some cases and careful microsurgery is associated with satisfactory clinical outcomes in appropriately selected cases.

Solitary Fibrous Tumor/Hemangiopericytoma of Spinal Cord: A Retrospective Single-Center Study of 16 Cases.

OBJECTIVE: In this study, we retrospectively reviewed our experience in the surgical management of solitary fibrous tumor (SFT)/hemangiopericytomas (HPCs) of the spinal cord. METHODS: Sixteen patients with SFT/HPCs of the spinal cord were enrolled in this study. Data on clinical presentation, radiologic findings, histopathologic features, surgical treatment, adjuvant therapy, and prognosis were retrospectively reviewed. Kaplan-Meier curves and log-rank tests were used to identify the prognostic factors for recurrence and overall survival (OS). RESULTS: Our series included 6 men and 10 women, with a male/female ratio of 1:1.7. Magnetic resonance imaging (MRI) showed slightly hyperintense lesions on T2-weighted images for all 16 patients. All tumors showed positive immunohistochemical staining for signal transducer and activator of transcription 6. Statistical analysis of clinical data showed that age, gender, tumor location, tumor size, medullary compartment location, and Ki-67 index were not associated with recurrence and OS (P > 0.05). However, World Health Organization grade III was significantly associated with recurrence (P < 0.01). Gross total resection (GTR) and postoperative radiotherapy significantly reduced recurrence (P < 0.01 and P < 0.05), but only GTR showed remarkable benefits to improve OS (P < 0.05). CONCLUSIONS: SFT/HPCs of spinal cord are rare neoplasms with a propensity to recur. Hyperintensity on T2-weighted magnetic resonance imaging combined with positive immunohistochemical staining for signal transducer and activator of transcription 6 are important clues for classification and differentiation of these tumors. The extent of resection, World Health Organization grade, and postoperative radiotherapy might be predictive factors for recurrence. Complete tumor resection should be sought whenever possible, and adjuvant radiotherapy is recommended after surgical resection. Moreover, regular and long-term follow-up is mandatory to monitor recurrence.

Analyses of prognosis-related factors of intracranial solitary fibrous tumors and hemangiopericytomas help understand the relationship between the two sorts of tumors.

Increasing evidence has suggested a close relationship between solitary fibrous tumors (SFTs) and hemangiopericytomas (HPCs) in the central nervous system (CNS). However, CNS SFTs differentiate from HPCs in their clinical behavior and patient prognoses. Analyses of prognosis-related factors can help clarify the relationship between SFT and HPC. The intracranial SFT and HPC cases treated in our departments from January 2002 to December 2012 were retrospectively reviewed. The SFT and HPC cases were also combined into an SFT/HPC group. The factors associated with patient progression-free survival (PFS) and overall survival (OS) were statistically analyzed using uni- and multivariate analyses. Fifty-eight intracranial SFT/HPC patients including 38 SFT patients and 20 HPC patients were treated during this period. The "Marseille grading" evaluated upon the histological aggressive phenotypes was applied in this study. The grading reflected a malignant progression ranging from "conventional" SFTs (grade I) to WHO III HPCs (grade III), and grade was negatively correlated with the PFS and OS of the SFT, HPC and SFT/HPC patients (P < 0.05).The multivariate analyses revealed that gross total resection (GTR) was significantly positively correlated with PFS and OS in the SFT, HPC and SFT/HPC patients and that radiotherapy was significantly positively correlated with PFS in the HPC and SFT/HPC patients (P < 0.05). In conclusion, the intracranial SFTs and HPCs share common prognostic factors including extent of surgery and pathology, moreover, the histological grading of the aggressive phenotypes supports the unifying of the CNS SFT and HPC into one tumor entity of SFT/HPC.

Extraventricular neurocytoma in pediatric populations: A case report and review of the literature.

Extraventricular neurocytomas (EVNs) are rare neuronal tumors included in the definition of neoplasms in the 2007 World Health Organization classification of tumors of the central nervous system. Although a small case series of EVNs in adults has been previously reported, EVNs in pediatric populations are extremely rare. The current case report presents the clinicopathological features of an EVN in a 2-year-old female who presented with nausea and vomiting that had lasted for five days. In addition, an analysis of the imaging features, histology, treatment and prognosis of these reported rare lesions is presented. Immunohistochemically, EVNs are characterized by the robust expression of synaptophysin, but with a lack of oligodendrocyte transcription factor 2, isocitrate dehydrogenase enzyme isoform 1 (IDH1) R132/IDH2 R172 mutations and p53 immunoexpression. The treatment for EVNs in pediatric and adult populations is gross total resection, with post-operative radiation reserved for subtotal resection or recurrent disease. In addition, drop metastasis must be carefully avoided.

Conus medullaris schistosomiasis.

OBJECT: The authors performed a study to investigate the clinical manifestations, treatment strategies, and possible pathogenesis of conus medullaris schistosomiasis. METHODS: Six cases collected from the authors' experience and four cases reported in the literature were studied retrospectively for clinical manifestations, treatment outcomes, and prognosis. All patients experienced progressive lower-extremity weakness and functional bowel and bladder impairment. Although the magnetic resonance (MR) imaging results suggested the presence of a conus medullaris tumor, schistosomiasis was diagnosed based on pathological results obtained in the 10 patients. The results of surgery followed by pyquiton and hormone treatment confirmed the diagnosis, and the patients' prognoses were good. CONCLUSIONS: This pathological entity is predominantly found in adults, and the clinical manifestations have no specificity, although the MR imaging may provide some clues. As a form of ectopic schistosomiasis, conus medullaris schistosomiasis deserves special consideration and further exploration. If an early diagnosis can be made and pyquiton and hormone therapy is given, surgery can be avoided and the prognosis will remain good.

[Molecular mechanism of LRIG1 cDNA-induced apoptosis in human glioma cell line H4].

BACKGROUND & OBJECTIVE: Leucine-rich repeats and immunoglobulin-like domains 1(LRIG1)is a kind of transmembrane glycoprotein,which is induced by epidermal growth factor (EGF),and develops inhibitory negative feedback by specific binding with epidermal growth factor receptor (EGFR). This research was to explore the molecular mechanism of LRIG1 inhibiting EGFR signal pathway. METHODS: Plasmid p3XFLAG-CMV9-LRIG1 was transfected into neuroglioma cell line H4. Changes of LRIG1 and EGFR expression at mRNA and protein levels were measured by RT-PCR and Western blot, respectively. Changes of cell proliferation and apoptosis were analyzed by MTT and flow cytometry methods. RESULTS: LRIG1 mRNA level in p3XFLAG-CMV9-LRIG1 transfected H4 cells (1.997+/-0.114) was significantly higher than that in control H4 cells (0.500+/-0.031),and p3XFLAG-CMV9 transfected group (0.357+/-0.035) (P< 0.001). LRIG1 protein level in p3XFLAG-CMV9-LRIG1 transfected H4 cells (1.790+/-0.119) was significantly higher than that in control H4 cells (0.717+/-0.038, P< 0.001), and p3XFLAG-CMV9 transfected H4 cells (0.930+/-0.076, P=0.001). EGFR mRNA level in p3XFLAG-CMV9-LRIG1 transfected H4 cells (0.463+/-0.033) was significantly lower than that in control H4 cells (1.157+/-0.067, P< 0.001), and p3XFLAG-CMV9 transfected H4 cells (0.933+/-0.058, P=0.002). EGFR protein level in p3XFLAG-CMV9-LRIG1 transfected H4 cells (0.703+/-0.067) was significantly lower than that in control H4 cells (1.280+/-0.078, P=0.003),and p3XFLAG-CMV9 transfected H4 cells (1.163+/-0.068,P=0.009). Apoptosis rate in LRIG1-transfected H4 cells (18.89%)was lower than that in control H4 cells (3.11%), and vector-transfected H4 cells (5.42%, P< 0.001). CONCLUSION: LRIG1 participates in construction of negative feedback loop of EGFR, which may inhibits growth of glioma cells.

Dosimetric characteristics of the Leipzig surface applicators used in the high dose rate brachy radiotherapy.

The nucletron Leipzig applicator is designed for (HDR) 192Ir brachy radiotherapy of surface lesions. The dosimetric characteristics of this applicator were investigated using simulation method based on Monte Carlo N-particle (MCNP) code and phantom measurements. The simulation method was validated by comparing calculated dose rate distributions of nucletron microSelectron HDR 192Ir source against published data. Radiochromic films and metal-oxide-semiconductor field-effect transistor (MOSFET) detectors were used for phantom measurements. The double exposure technique, correcting the nonuniform film sensitivity, was applied in the film dosimetry. The linear fit of multiple readings with different irradiation times performed for each MOSFET detector measurement was used to obtain the dose rate of each measurement and to correct the source transit-time error. The film and MOSFET measurements have uncertainties of 3%-7% and 3%-5%, respectively. The dose rate distributions of the Leipzig applicator with 30 mm opening calculated by the validated MC method were verified by measurements of film and MOSFET detectors. Calculated two-dimensional planar dose rate distributions show similar patterns as the film measurement. MC calculated dose rate at a reference point defined at depth 5 mm on the applicator's central axis is 7% lower than the film and 3% higher than the MOSFET measurements. The dose rate of a Leipzig applicator with 30 mm opening at reference point is 0.241+/-3% cGy h(-1) U(-1). The MC calculated depth dose rates and profiles were tabulated for clinic use.

Microelectrode-guided technique for treatment of Parkinson's diseases.

From May, 2000 to June, 2001, 27 patients with Parkinson disease (PD), including 10 cases of rigidity, 13 cases of tremor, 4 cases of rigidity and tremor, were treated by microelectrode-guided technique. Among them, phlebotomy was carried out in 17 cases and thalamotomy in 10 cases. All the targets of lesion were anatomically located by using MR and neurophysiological signals on microelectrode. Our results showed that the efficiency of microelectrode-guided technique for treatment of PD was 98%. The postoperative unified parkinson disease rating scale were 12.3 +/- 9.1 and 13.2 +/- 8.9 respectively, which significantly improved as compared with those before operation. It was concluded that by recognizing special electrical signals in neurons microelectrode-guided neuropsychological techniques can locate target at cellular level, which overcomes the individual difference in anatomy and function, and allow more accuracy, safety and efficiency of operation. This is especially true of PD patients who fail to respond to medical treatment.