DJ-1 protects cell death from a mitochondrial oxidative stress due to GBA1 deficiency

BACKGROUND

GBA1 mutations are the most common genetic risk factor for development of Parkinson's disease (PD). The loss of catalytic activity in GBA1, as well as the reduction of the GBA1 protein in certain cellular compartment, may increase disease progression. However, the mechanisms underlying cellular dysfunction caused by GBA1 deficiency are still mostly unknown.

OBJECTIVE

In this study, we focus on the genetic interaction between GBA1 deficiency and PD-causing genes, such as DJ-1, in mitochondrial dysfunction.

METHODS

GBA1 knockout (KO) SH-SY5Y cells were used to assess DJ-1 functions against oxidative stress in vitro. The levels of cellular reactive oxygen species were monitored with MitoSOX reagent. The expression of the PARK7 gene was analyzed using the quantitative real-time PCR (qRT-PCR). To understand the mechanism underlying DJ-1 upregulation in GBA1 KO cells, we assess ROS levels, antioxidant protein, and cell viability in GBA1 KO cells with treatment of ROS inhibitor N-acetyl-cysteine or miglustat, which is an inhibitor of glucosylceramide synthase. Dopaminergic degeneration was assessed from Gba1 L444P heterozygous mice mated with Park7 knockout mice.

RESULTS

We find that DJ-1 is significantly upregulated in GBA1 KO cells. Elevated levels of DJ-1 are attributed to the transcriptional expression of PARK7 mRNA, but not the inhibition of DJ-1 protein degradation. Because DJ-1 expression is highly linked to oxidative stress, we observe cellular reactive oxygen species (ROS) in GBA1 KO cells. Moreover, several antioxidant gene expressions and protein levels are increased in GBA1 KO cells. To this end, GBA1 KO cells are more susceptible to H2O2-induced cell death. Importantly, there is a significant reduction in dopaminergic neurons in the midbrain from Gba1 L444P heterozygous mice mated with Park7 knockout mice, followed by mild motor dysfunction.

CONCLUSION

Taken together, our results suggest that DJ-1 upregulation due to GBA1 deficiency has a protective role against oxidative stress. It may be supposed that mutations or malfunctions in the DJ-1 protein may have disadvantages in the survival of dopaminergic neurons in the brains of patients harboring GBA1 mutations.

P18.04.A Cay10603, HDAC6 inhibitor, enhances radiosensitivity in meningioma via supressing the nuclear beta-catenin accumulation

Background

Meningioma is the most frequent primary central nervous system tumour (PCNST) which account ca 36% of all PCNST. Due to the lack of efficient chemotherapy for meningioma, radiotherapy often become a first-line treatment especially when the tumour is not operable. Radiotherapy plays a crucial role in local control but its efficacy is restricted by radioresistance and by normal tissue radiation tolerance. Therefore, developing and evaluating potential radiosensitisers to enhance therapeutic efficacy are needed.Histone deacetylase (HDACs) expression is generally increased in many cancer types and regulate the expression of numerous proteins involved in tumorigenesis. Targeting HDAC using HDAC inhibitor (HDACi) represent promising radiosensitisers that affect various biological processes, such as cell survival, apoptosis, and DNA repair.

Material and Methods

We investigated whether pre-treatment with the hydroxamate-based HDAC6 inhibitor, Cay10603, impacts radiation-induced DNA double-strand break (DSB) induction, cell survival, cell cycle arrest, and cell death using immunocytochemistry, clonogenic assay, and flow cytometry in meningioma cell lines. Low concentration (100 nM) of Cay10603 was treated 24 hr prior to high energy x-ray irradiation (2 Gy) by a medical linear accelerator (LINAC). To investigate the nuclear localisation of beta-catenin, subcellular fractionation and Western Blotting were conducted.

Results

We found that tumour cells survival was synergistically decreased after combination treatment of Cay10603 and radiation. Combination therapy induced DNA damage with activation of histone gH2AX and increased G2/M arrest compared to drug or radiation alone. Both apoptotic and necrotic cell death were increased after combination therapy. To focus on the mechanisms of action of HDAC6 inhibition followed by radiation, we further investigated nuclear localisation of beta-catenin levels. The results showed the both beta-catenin and c-myc expression in the nucleus was suppressed after combination therapy.

Conclusion

In meningioma cells, radiotherapy in combination with HDAC6 inhibitor reduces the nuclear localisation of beta-catenin and synergistically decreases cell survival. Our findings demonstrate a potential therapeutic strategy of Cay10603 to improve the radiosensitisation for meningioma cells.

Why People Trust Something Other than Science: Cases of Acupuncture and Four Pillars of Destiny in Korea

In modern society, people are expected to make scientific decisions and rational actions over a range of personal and social problems. There have been a number of studies on students' and adults' decision-making over socio-scientific issues under the name of scientific literacy. In this study, we investigated the social and cultural backgrounds of Korean people's actions and trust over their personal problems (e.g. health, career choice), by conducting in-depth interviews with ten Korean adults on their experience related to acupuncture and Four Pillars of Destiny (FPD), two representative examples of unorthodox sciences. The analysis of the data reveals that their actions concerning acupuncture and FPD are influenced by socio-cultural factors (esp. family culture, social system) and by their understandings of the nature of science. In addition, we found that there are a different set of reasons and varying degrees of people's trust between acupuncture and FPD. Based on the results, we discussed the needs to introduce wider concepts of the nature of science and of the scopes of science education.

[Clinical analysis of children with cardiac syncope caused by anomalous origin of the left coronary artery from the right sinus]

Objective: To analysis the clinical characteristics and to summarize therapy experience of pediatric patients with cardiac syncope caused by anomalous origin of the left coronary artery from the right sinus (ALCA-R). Methods: We retrospectively analyzed the clinical data including clinical manifestations, myocardial injury biomarkers, radiological features, treatments and prognoses of pediatric patients with ALCA-R who were admitted to Beijing Children's Hospital from November 2015 to June 2018. Results: Four female patients were included in this analysis, age of onset was 7 to 14 years. All the patients presented with exercise-induced syncope and acute myocardial infarction. During the course, three patients presented with acute left heart failure, and one patient had history of sudden cardiac arrest. Laboratory data showed significant elevation of both the creatine kinase and troponin levels in four patients. All electrocardiogram (ECG) showed left main coronary artery occlusion, echocardiography suggested the possible anomalous origin of the left coronary artery in one child. Coronary CT angiography (CTA) revealed there was no coronary ostium in the left coronary sinus, and the left coronary artery had an anomalous origin from the right sinus. The left main coronary artery passed between the ascending artery and the root of the main pulmonary artery, which was compressed by these two large vessels. Two patients underwent cardiac magnetic resonance examination, which detected late gadolinium enhancement in ALCA-R with an interarterial course. Unroofing of the left coronary ostium (cut-back procedure) was performed in two patients, and the other two patients who were not operated were recommended to restrict their physical activities. During a regular follow-up period of 12-43 months, all the children survived without recurrent cardiovascular event. Conclusion: If an adolescent presents with exercise-induced syncope, acute myocardial infarction and even sudden death, and ECG shows left main coronary artery occlusion characteristics, we should consider the possibility of developmental abnormality of coronary artery, particularly the ALCA-R. Once diagnosed as ALCA-R, patients should be recommended to avoid strenuous activities，early recognition and surgical treatment are imperative for these patients.

[Analysis of four children with anomalous origin of the left coronary artery from the right sinus with interarterial course]

Objective: To investigate the clinical features and improve the diagnosis and treatment of anomalous origin of the left coronary artery from the right coronary sinus with an interarterial course (ALCA-R-IAC) between the ascending aorta and main pulmonary artery in children. Methods: A retrospective analysis of the clinical manifestation, laboratory test, radiological feature, treatment and prognosis were conducted in four female children presented with ALCA-R-IAC in Beijing Children's Hospital from November 2015 to June 2018. Results: The four girls with onset age of 7.5-14.7 years were diagnosed with ALCA-R-IAC by CT coronary angiography (CTCA). Four children presented with exercise-induced syncope and clinical manifestations of acute myocardial infarction including 3 patients with acute left heart failure, 1 cardiogenic shock and 1 cardiac arrest. Nervous system involvement was found in one patient. Troponin I increased significantly to 20.65-50.00 μg/L in the four patients. Electrocardiogram (ECG) developed signs of left main coronary artery involvement. Echocardiography revealed reduced left ventricular ejection fraction (LVEF) of 25%-45% in three children and suspected anomalous origin of the left coronary artery in one child. CTCA showed an anomalous left coronary artery originating from the right coronary sinus, which had an interarterial course between the aorta and pulmonary artery leading to a slim left main coronary trunk. Two children underwent unroofing procedure and the other two children in whom physical activities were restricted received conservative managements. During a regular follow-up period of 12-43 months, all the children survived without recurrent symptoms and had good prognosis. Conclusions: ALCA-R-IAC can present as exercise-related syncope and acute myocardial infarction, even sudden death in children and adolescents. CTCA is helpful to clarify the early diagnosis of ALCA-R-IAC. Surgical intervention is the main treatment for ALCA-R-IAC and strenuous physical activities should be avoided.

Abstract P6-09-02: Associations between hereditary cancer panel predisposition genes and breast cancer histological subtypes

Background: Clinical panel testing has become routine practice for patients that are diagnosed with breast cancer at a young age and/or have a personal or family history of cancer. Associations with known breast cancer genes and breast cancer subtypes have been previously identified, such as BRCA1 associations with estrogen receptor negative (ER-) and triple negative (ER-/PR-/HER2-) breast cancers. However, the cancer predisposition genes associated with each of the four clinical subtypes of breast cancer have not been fully defined. We evaluated 24,901 Caucasian female breast cancer cases receiving clinical panel testing for 23 cancer predisposition genes and assessed associations between mutations in each gene and breast cancer subtypes.

Methods: Germline hereditary cancer multigene panel testing results for cancer predisposition genes were obtained for 24,901 Caucasian female breast cancer cases evaluated by a clinical testing laboratory. Information on tumor histology, personal and family history of cancer, age at diagnosis, and previous genetic testing was provided by clinical care providers of patients receiving clinical cancer genetic testing. Breast cancer cases were classified into clinical breast cancer subtypes based on estrogen/progesterone hormone receptor status (HR) and HER2 status: Luminal A (HR+/HER2-), Luminal B (HR+/HER2-), HER2 subtype (HR-/HER2+), and Triple Negative (HR-/HER2-). The frequency of pathogenic or likely pathogenic mutations observed in each subtype was compared against the Exome Aggregation Consortium (ExAC) non-TCGA non-Finnish European population to estimate risks.

Results: ATM was associated with moderate risks (odds ratio (OR)>2.0) of Luminal A, Luminal B, and HER2 subtypes of breast cancer, but was not associated with the Triple Negative subtype. PALB2 was associated with moderate risk for Luminal B subtype, but high risk (OR>5.0) for Luminal A, HER2, and triple negative subtypes. TP53 was associated with high risks for Luminal B and HER2 tumors. NBN, MRE11A, and RAD50 were not associated with any subtype of breast cancer.

Conclusions: Identifying associations between inherited mutations (odds ratio (OR)>2.0) and breast cancer subtypes can inform clinical risk management, treatment options, and therapeutic development efforts.

Citation Format: Lilyquist J, Laduca H, Hu C, Na J, Polley EC, Hart SN, Pesaran T, Tippin-Davis B, Goldgar DE, Dolinsky JS, Couch FJ. Associations between hereditary cancer panel predisposition genes and breast cancer histological subtypes [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-09-02.

In vivo skin reactions from pulsed-type, bipolar, alternating current radiofrequency treatment using invasive noninsulated electrodes

BACKGROUND

Bipolar, alternating current radiofrequency (RF) conduction using invasive noninsulated electrodes consecutively generates independent tissue coagulation around each electrode and then, the converged coagulation columns.

METHODS

Two pulsed-type RF models at the on-time pulse width/pulse pack of 30 and 40 milliseconds were designed to amplify the early stage of RF-induced tissue reaction using hairless mouse skin in vivo. Then, structural and ultrastructural changes were evaluated in hairless mouse skin samples at baseline and immediately 1 day, 3 days, 7 days, and 14 days after treatment.

RESULTS

Immediately after pulsed-RF treatment, a few chrysanthemum-like zones of electrothermal coagulation and hypereosinophilic collagen fibers were found in the dermis and dermo-subcutaneous fat junction. Histochemical staining for periodic acid-Schiff and immunohistochemical staining for type IV collagen revealed marked thickening of basement membranes. Transmission electron microscopy demonstrated that pulsed-RF treatment resulted in higher electron-dense and remarkably thicker lamina densa, as well as increases in anchoring fibrils, compared with untreated control specimens. Furthermore, CD31-positive blood vessels were smaller in size with a slit-like luminal appearance, without excessive damage to endothelial cells.

CONCLUSION

Our data indicated that pulse-type, bipolar RF energy induces structural and ultrastructural changes in basement membranes and vascular components in hairless mouse skin.

Abstract S2-01: Breast cancer risks associated with mutations in cancer predisposition genes identified by clinical genetic testing of 60,000 breast cancer patients

Clinical genetic testing panels are broadly used to gather information about cancer predisposition in individuals with personal and/or family history of breast cancer. However, the involvement of several of the genes on clinical testing panels in predisposition to breast cancer, such as MRE11A and RAD50, has recently come into question. In addition, accurate risk estimates for breast and other cancer are not well defined for the majority of genes on testing panels. We studied 60,000 women diagnosed with breast cancer who were tested for germline cancer predisposing mutations using hereditary cancer gene panels. Information on personal and family cancer history, age of diagnosis, and ethnicity of patients was obtained from test requisition forms. Greater than 90% met National Comprehensive Cancer Network HBOC testing criteria. To estimate gene-specific risks for breast cancer, case-control analyses were performed comparing the frequencies of pathogenic mutations from Caucasian cancer cases with frequencies from Caucasian, non-Finnish, non-TCGA controls from the Exome Aggregation Consortium (ExAC) database. Mutations were detected in 9% of breast cancer patients. Twelve genes displayed a significant association (p<0.05) with breast cancer. Nine of these genes, including ATM, RAD51D, NF1, and MSH6, were associated with moderate risk (RR>2.0) of breast cancer and three genes (BRCA1, BRCA2, PALB2) were associated with high risk (RR>5.0) of breast cancer. Cumulative age-dependent risk models were developed for each gene. This large clinical testing dataset of 60,000 women with breast cancer provides useful data for many predisposition genes previously lacking risk estimates, and should prove useful for clinical risk management of patients with inherited mutations in these genes.

Citation Format: Couch FJ, Hu C, Lilyquist J, Shimelis H, Akinhanmi M, Na J, Polley EC, Hart SN, McFarland R, LaDuca H, Huether R, Goldgar DE, Dolinsky JS. Breast cancer risks associated with mutations in cancer predisposition genes identified by clinical genetic testing of 60,000 breast cancer patients [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S2-01.

Abstract P5-09-03: Associations between breast cancer subtypes and mutations in cancer predisposition genes identified by clinical genetic testing of breast cancer patients

Clinical genetic testing of individuals with a personal or family history of breast and ovarian cancer using panels for BRCA1/2 and other candidate cancer predisposition genes has become routine clinical practice. Several of the genes on hereditary cancer testing panels have been strongly associated with specific subtypes of breast cancer. In particular, individuals with germline mutations in BRCA1 predominantly develop estrogen receptor (ER)-negative and triple negative (TN) (estrogen receptor negative, progesterone receptor negative, HER2 negative) breast tumors. In contrast, CHEK2 and ATM mutations have been associated with ER-positive breast cancer. In this study, associations between mutations in panel genes and breast cancer subtypes were evaluated. A cohort of 60,000 breast cancer patients tested for germline cancer predisposing mutations using hereditary cancer gene panels was utilized. Information on personal and family cancer history, age of diagnosis, tumor pathology, and ethnicity of patients was obtained from test requisition forms or by follow up with ordering health care providers. Mutations in each gene were combined into four histological subtypes (triple negative; HER2 positive; ER-positive,HER2-positive; and ER-positive,HER2 negative). Associations for each subtype were estimated by case-control analyses comparing the frequencies of pathogenic mutations in each subtype with frequencies from non-TCGA controls from the Exome Aggregation Consortium (ExAC) database. In addition, case-case analyses were conducted to assess enrichment of gene mutations in specific breast cancer subtypes. Among the observed associations between genes and breast cancer subtypes, mutations in CHEK2 and ATM were highly enriched in luminal breast cancers and BARD1 was specifically associated with TN breast cancer. Refining the spectrum of pathological correlates with mutations in hereditary breast cancer genes will aid gene specific cancer risk management, and may accelerate the development of novel gene-specific therapeutic interventions.

Citation Format: Couch FJ, Lilyquist J, Na J, Hu C, Polley EC, Shimelis H, Akinhanmi M, McFarland R, LaDuca H, Goldgar DE, Dolinsky JS. Associations between breast cancer subtypes and mutations in cancer predisposition genes identified by clinical genetic testing of breast cancer patients [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-09-03.

CT angiography of the lower extremity and coronary arteries using 256-section CT: a preliminary study

AIM

To investigate the possible use of a 256-section computed tomography (CT) prospective electrocardiography (ECG)-gated wide volume scanning protocol for combined angiography of the lower extremity and coronary arteries, after a single injection of contrast medium, in patients with lower extremity peripheral arterial disease (PAD).

MATERIALS AND METHODS

Thirty-four patients with suspected PAD underwent CT angiography (CTA) with a prospective ECG-gated protocol that covered the level of the tracheal bifurcation to the foot sole. Digital subtraction angiography (DSA) of the lower extremity arteries was performed on patients requiring therapeutic intervention. Image quality and stenosis of the coronary and lower extremity arteries were assessed.

RESULTS

A total of 93.1% of the coronary segments were adequate for diagnosis. 17 (50%) patients showed coronary artery stenosis ≥50%. A total of 95.8% of the lower extremity arterial segments were adequate for diagnosis. Twenty-eight patients with severe lower extremity arterial stenosis or occlusion underwent DSA. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CTA for the detection of significant lower arterial stenosis (≥50%) was 94.8%, 97.2%, 95.3%, 96.9%, and 96.3%, respectively.

CONCLUSION

Using the prospective ECG-gated wide volume CTA protocol, images of the coronary and lower extremity arteries suitable for diagnosis can be acquired simultaneously after a single injection of contrast agent. In addition to accurately diagnosing PAD, combined angiography may be used to screen for coronary heart disease in patients with PAD.

Hydrogen peroxide reduces lead-induced oxidative stress to mouse brain and liver

Lead (Pb) intoxication may initiate many disorders in human and animals. This study investigates the role of exogenous hydrogen peroxide (H(2)O(2)) in inducing mouse tolerance to Pb exposure. Results showed that the simultaneous application of 1.2 microg H(2)O(2) per kg body weight efficiently protected mice against the Pb-caused injury, as revealed by decreased growth suppression caused by the Pb stress, increased antioxidative enzyme activity, reduced lipid peroxidation, and the protective effect on the nuclear DNA integrity. To our knowledge, this is the first finding of this sort.

Physiological Characterization of Synaptic Inputs to Inhibitory Burst Neurons From the Rostral and Caudal Superior Colliculus

The caudal superior colliculus (SC) contains movement neurons that fire during saccades and the rostral SC contains fixation neurons that fire during visual fixation, suggesting potentially different functions for these 2 regions. To study whether these areas might have different projections, we characterized synaptic inputs from the rostral and caudal SC to inhibitory burst neurons (IBNs) in anesthetized cats. We recorded intracellular potentials from neurons in the IBN region and identified them as IBNs based on their antidromic activation from the contralateral abducens nucleus and short-latency excitation from the contralateral caudal SC and/or single-cell morphology. IBNs received disynaptic inhibition from the ipsilateral caudal SC and disynaptic inhibition from the rostral SC on both sides. Stimulation of the contralateral IBN region evoked monosynaptic inhibition in IBNs, which was enhanced by preconditioning stimulation of the ipsilateral caudal SC. A midline section between the IBN regions eliminated inhibition from the ipsilateral caudal SC, but inhibition from the rostral SC remained unaffected, indicating that the latter inhibition was mediated by inhibitory interneurons other than IBNs. A transverse section of the brain stem rostral to the pause neuron (PN) region eliminated inhibition from the rostral SC, suggesting that this inhibition is mediated by PNs. These results indicate that the most rostral SC inhibits bilateral IBNs, most likely via PNs, and the more caudal SC exerts monosynaptic excitation on contralateral IBNs and antagonistic inhibition on ipsilateral IBNs via contralateral IBNs. The most rostral SC may play roles in maintaining fixation by inhibition of burst neurons and facilitating saccadic initiation by releasing their inhibition.

Thalamic terminal morphology and distribution of single corticothalamic axons originating from layers 5 and 6 of the cat motor cortex

We investigated the axonal morphology of single corticothalamic (CT) neurons of the motor cortex (Mx) in the cat thalamus, using a neuronal tracer, biotinylated dextran amine (BDA). After localized injection of BDA into the Mx, labeled CT axons were found ipsilaterally in the thalamic reticular nucleus (TRN), the ventroanterior-ventrolateral complex (VA-VL), the central lateral nucleus (CL), the central medial nucleus, and the centromedian nucleus, but with the primary focus in the VA-VL. The terminals in the VA-VL formed a large laminar cluster, which extended approximately in parallel with the internal medullary lamina. The laminar organization mirrored morphologic features of single CT axons. We reconstructed the trajectories of 25 single CT axons that arose from layer V (16 axons) or layer VI (9 axons) and terminated in the VA-VL. Terminals of single CT axons that originated from both layer V and layer VI were confined within a laminar structure about 700 microm thick, suggesting the existence of laminar input organization in the VA-VL. Otherwise, the two groups of the CT axons showed contrasting features. All of the CT axons derived from layer VI gave rise to a few short collaterals to the TRN and then formed extensive arborization with numerous small, drumstick-like terminals in the VA-VL. On the other hand, the CT axons arising from layer V gave rise to collaterals whose main axons descended into the cerebral peduncle. Each collateral projected to the VA-VL or CL without projection to the TRN and formed a few small clusters of giant terminals. The two groups of CT neurons in the same cortical column had convergent rather than segregated termination in the VA-VL. However, the terminals of layer VI CT neurons were distributed diffusely and widely in the VA-VL, whereas the terminals of layer V CT neurons were much more focused and surrounded by the terminals of the former group. These contrasting features of the two types of CT projections appear to represent their different functional roles in the generation of motor commands and control of movements in the Mx.

[Primitive neuroectodermal tumor of bone and soft tissue]

OBJECTIVE

To study the pathological characteristics of primitive neuroectodermal tumor (PNET) of bone and soft tissue.

METHOD

Five patients with bone and soft tissue of PNET (2 men and 3 women) were studied by light microscope and immunohistochemistry. The age of the patients was 18, 18, 43, 14, 32 years and the primary sites of involvement were the ilium (n = 2), axillary fossa (n = 1), condyle of femur (n = 1), and diploe (n = 1). X-ray films showed bone osteolytic destruction, and no periosteal reaction or calcification. Surgery was performed in the patients.

RESULT

All patients received combined chemotherapy and 3 received radiotherapy. Three patients died of metastatic tumor of lung 20, 13, and 5 months after invasion. 1 patient metastatic tumor of lung 20 months after invasion, and 1 patient bone extensive metastasis 1.5 months after surgery.

CONCLUSION

The treatment of PNET of bone and soft tissue awaits further study.

[Clinico-pathologic study of Ewing's sarcomas of bone and soft tissue and peripheral primitive neuroectodermal tumors]

OBJECTIVE

To study the diagnosis and differentiation of EW and PNET.

METHODS

Fourteen cases of Ewing's sarcomas (EW) and peripheral primitive neuroectodermal tumors (PNET) were studied by light microscopy, immunohistochemistry and electron microscopy (EM). Twelve cases were followed up. Schmidt criterion was used for the differential diagnosis of EW and PNET.

RESULTS

There were 6 cases of EW and 8 cases of PNET. Six of 8 PNET cases had Homer-Wright (H-W) rosettes. In this series, 12/14 cases were positive for O13 (HBA71) staining. NSE was positive in 3 cases of EW. All PNET cases were positive for neural markers, and 5 of them were positive for more than two of these markers. Electronmicroscopically, there were neurosecretory granules (4/4 cases), nerve-like protrusions and microfilaments (1/4 case) in PNET. In 3 of 6 EW and 1 of 6 PNET, PAS staining was positive. During the follow-up period from 2 months to 5 years, 3 cases with intraosseous EW remain alive and free of tumor. The remaining patients are dead or having their tumors metastasized.

CONCLUSION

EW is more primitive in cell differentiation, while PNET has more neural differentiation. The presence of H-W rosettes is an important morphologic feature of PNET. To differentiate EW from PNET is of clinical significance O13 is a useful marker for the diagnosis of EW/PNET.

Cerebellar input to corticothalamic neurons in layers V and VI in the motor cortex

To investigate whether corticothalamic (CT) neurons in the motor cortex (Mx) receive cerebellar input via the ventroanterior-ventrolateral nucleus of the thalamus (VA-VL), we recorded intracellular potentials from neurons in the Mx of anesthetized cats and examined effects of stimulation of the VA-VL and the brachium conjunctivum on them. After this electrophysiological identification, horseradish peroxide (HRP) was injected iontophoretically into the recorded neurons for morphological analysis. We identified 34 neurons as CT neurons by their antidromic response to stimulation of the VA-VL, of which 13 were layer VI CT neurons and 21 were layer V CT neurons. A majority of the CT neurons of both layers VI and V received monosynaptic excitatory postsynaptic potentials (EPSPs) from the VA-VL and di- or polysynaptic EPSPs from the cerebellum. The laminar distribution and morphological characteristics of single CT neurons receiving cerebellar input were analyzed on 19 HRP-labeled CT neurons. Eight layer V and six layer VI CT neurons were reconstructed from serial sections. All the reconstructed layer VI CT neurons were modified pyramidal neurons whose apical dendrites ended in layer III or V, and all the stained layer V CT neurons were typical pyramidal neurons, although the laminar and tangential distribution of recurrent collaterals of these neurons varied from neuron to neuron.

Four convergent patterns of input from the six semicircular canals to motoneurons of different neck muscles in the upper cervical cord

This study was performed to investigate the pattern of input and the pathways from the six semicircular canals to motoneurons of various neck muscles in anesthetized cats. Intracellular postsynaptic potentials from neck motoneurons were recorded in response to electrical stimulation of the six ampullary nerves. The results showed that motoneurons of a particular neck muscle have a homogeneous convergent pattern of input from the six semicircular canals; there are four patterns of input from the six semicircular canals to motoneurons of various neck muscles; and the trisynaptic connection between the semicircular canal nerves and neck motoneurons was identified in addition to the disynaptic connection.

Ki-67 antigen expression in hepatocellular carcinoma using monoclonal antibody MIB1. A comparison with proliferating cell nuclear antigen

To evaluate the prognostic significance and clinicopathologic correlation of proliferative activity in patients with hepatocellular carcinoma, Ki-67 antigen expression was examined using immunohistochemical staining with monoclonal antibody MIB1. Seventy-two patients (65 men, 7 women; age range 24-77 years, mean, 52 years) having hepatocellular carcinoma surgically resected were studied. Tumor and nontumorous tissues were stained with monoclonal antibody MIB1 with microwave oven pretreatment. Tumor and nontumor MIB1 (T-MIB1 and NT-MIB1) scores were assessed by counting the positive staining nuclei per 1,000 cells. The T-MIB1 score ranged from 5-630 per 1,000 cells (mean +/- standard deviation [SD] = 145 +/- 162). It was found to be significantly higher in less well-differentiated tumors (Edmondson's grades III and IV) than in well-differentiated ones (Edmondson's grades I and II) (P = .017). The T-MIB1 score was also higher in nonencapsulated tumors than in encapsulated ones, although it did not reach statistical significance (P = .069). It had no influence on tumor size, tumor invasiveness, the background disease in the nontumorous livers, patients' HBsAg status, or serum alpha-fetoprotein levels. Diseases in the nontumorous livers or patients' HBsAg status had no influence on the NT-MIB1 scores. When the tumors were stratified into two groups with T-MIB1 score < or = 20 and T-MIB1 score > 20, those patients with score < or = 20 had significantly longer disease-free survival (DFS) than those with scores > 20 (median DFS: 34 months and 4.7 months, respectively; P = .011). In addition, MIB1 and PCNA were closely correlated (P < .01). The authors conclude that proliferative activity in hepatocellular carcinoma, as defined by MIB1 immunohistochemical analysis, is significantly related to tumor cellular differentiation. It is also a potentially valuable prognostic factor in patients with this tumor.

Design of an optical content-addressable parallel processor for expert systems

The slow execution speed of current rule-based systems (RBS's) has restricted their application areas. To improve the speed of RBS's, researchers have proposed various electronic multiprocessor systems as well as optical systems. However, the electronic systems still suffer in performance from the large amount of required time-consuming pattern-matching and comparison operations at the core of RBS's. And optical systems do not fully exploit the available parallelism in RBS's. We propose an optical content-addressable parallel processor for expert systems. The processor executes the three basic RBS operations, match, select, and act, in a highly parallel fashion. Additionally, it extracts and exploits all possible parallelism in a RBS. Distinctive features of the proposed system include the following: (1) two-dimensional representation of data (knowledge) and control information to exploit the parallelism of optics in the three RBS units; (2) capability of processing general-domain knowledge expressed in terms of variables, numbers, symbols, and comparison operators such as greater than and less than; (3) the parallel optical match unit, which performs the two-dimensional optical pattern matching and comparison operations; (4) a novel conflict-resolution algorithm to resolve conflicts in a single step within the optical select unit. The three units and the general-knowledge representation scheme are designed to make the optical content-addressable parallel processor for expert systems suitable for any high-speed general-purpose RBS.

Cerebellar and cerebral inputs to corticocortical and corticofugal neurons in areas 5 and 7 in the cat

1. In the parietal cortex (Px, areas 5 and 7), the organization and characteristics of cerebellar and cerebral inputs and their effects on efferent neurons were investigated with the use of intracellular and extracellular recording techniques in the anesthetized cat. 2. Evoked field potential analysis revealed that two regions of the Px, the caudal bank of the ansate sulcus (Ans. S.) and the crown of the suprasylvian gyrus (Ssyl. G.), received converging input from the dentate and the interpositus nucleus. The cerebellar input to the caudal bank of the Ans. S. was relayed via the ventrolateral region of the ventroanterior-ventrolateral (VA-VL) complex of the thalamus, whereas the cerebellar input to the crown of the Ssyl. G. was relayed via the dorsomedial region of the VA-VL complex. 3. A total of 176 neurons was recorded intracellularly in the Px to examine inputs from the cerebellum. Of these, 72 neurons were corticocortical neurons projecting to the motor cortex (Mx), and 48 were corticofugal neurons to the pontine nucleus (PN). Intracellular staining with horseradish peroxidase revealed that the former corticocortical neurons were layer III pyramidal neurons and the latter corticofugal neurons were layer V pyramidal neurons. 4. Stimulation of the brachium conjunctivum (BC) produced di- or polysynaptic excitatory postsynaptic potentials (EPSPs) in corticocortical neurons projecting to the Mx and corticofugal neurons to the pontine nucleus in the Px. The characteristics of BC-evoked EPSPs were different between the bank of the Ans. S. and the crown of the Ssyl. G. In the bank of the Ans. S., the slope of the rising phase of the BC-evoked EPSPs was steeper, and their minimum latency was shorter by 0.8 ms than those in the crown of the Ssyl. G. These differences may reflect differences in the terminal distribution and conduction velocity of the thalamocortical fibers relaying cerebellar input to these two parietal areas. 5. Stimulation of the Mx produced mono- or disynaptic EPSPs in both corticocortical neurons projecting to the Mx and corticofugal neurons projecting to the pontine nucleus in the Px. For each neuron, effective sites for inducing EPSPs were distributed very widely and sometimes covered both areas 4 and 6. Extensive corticocortical projection from the Mx to the Px was confirmed by injection of an anterograde tracer into the Mx. 6. These data indicate that neurons in the Px receive inputs from both the cerebellum and the Mx and send outputs to the Mx and the cerebellum.(ABSTRACT TRUNCATED AT 400 WORDS)

Constant-time parallel sorting algorithm and its optical implementation using smart pixels

Sorting is a fundamental operation that has important implications in a vast number of areas. For instance, sorting is heavily utilized in applications such as database machines, in which hashing techniques are used to accelerate data-processing algorithms. It is also the basis for interprocessor message routing and has strong implications in video telecommunications. However, high-speed electronic sorting networks are difficult to implement with VLSI technology because of the dense, global connectivity required. Optics eliminates this bottleneck by offering global interconnects, massive parallelism, and noninterfering communications. We present a parallel sorting algorithm and its efficient optical implementation. The algorithm sorts n data elements in few steps, independent of the number of elements to be sorted. Thus it is a constant-time sorting algorithm [i.e., O(1) time]. We also estimate the system's performance to show that the proposed sorting algorithm can provide at least 2 orders of magnitude improvement in execution time over conventional electronic algorithms.

Modeling and simulation methodology for digital optical computing systems

A modeling and simulation methodology for digital optical computing systems is introduced in this paper. The methodology predicts maximum performance of a given optical computing architecture and evaluates its feasibility. As an application example, we apply this methodology to evaluate the feasibility and performance of the optical content-addressable parallel processor proposed in Appl. Opt. 31, 3241 (1992). The approach consists of two major phases. The first phase involves analytical studies of the effects of design parameters such as cross talk, diffraction-limited beam spot diameter, and pitch on system performance parameters such as signal packing density and skew time. In the second phase, a simulation model and a simulator are introduced by the use of GLAD (General Laser Analysis and Design, an optical software package developed by Applied Optics Research) to evaluate the combined effects of bit-error rate, bit rate, optical power efficiency, available source power, and signal contrast on the perfor ance parameters such as signal packing density, misalignment tolerance, and distance between devices. The methodology presented here investigates the model, not on a component-by-component basis, but as a whole, which produces a more realistic representation of the actual laborator prototype. The proposed methodology is intended to reduce the optical computing system design time as well as the design risk associated with building a prototype system.

Parallel electro-optical rule-based system for fast execution of expert systems

The slow execution speed of current rule-based systems has restricted their application areas. Multiprocessor architectures have been proposed to overcome this limitation. However, as the number of processors in a multiprocessor system grows, so does the cost of communication between processors or between processor and memory units. The use of optics for a fast and parallel implementation of rule-based systems is proposed. The proposed optical system is hybrid in nature, using electronics for the user interface and optics for the rule-based inference engine. The proposed system uses twodimensional planes as basic computational entities and is therefore able to provide concurrent rule processing. Furthermore, it provides highly efficient implementation of the basic operations needed in rule-based systems; namely, matching, selection, and rule firing. The execution speed of the proposed system is theoretically estimated and is shown to be potentially of orders of magnitude faster than current electronic system.

[Relation of HLA-I and HLA-DR to HBV-infected liver]

HLA-I and HLA-DR antigenic profiles of 34 livers with HBV infection and 15 non-HBV infected livers were analyzed. HLA-I antigen was detected on the membrane of the hepatocytes in 19 infected livers, but not in the non-HBV infected livers except in one congenital polycystic liver. The number of HLA-I Ag positive hepatocytes were correlated with the extent of the liver damage, and the positive rate of HLA-I was lower in the livers of the high HBV reduplication group (HBeAg+, HBeAb-) in comparing with the group with low HBV duplication (HBeAg-, HBeAb+). Only in two cases of chronic active hepatitis, HLA-DR Ag was detected to be expressed on the membrane of hepatocytes. The expression of HLA-I Ag on the membrane of liver cells may play a role in the recognition of hepatocytes as targets for cytotoxic T-lymphocytes which may represent an important event in the pathogenesis of hepatocellular necrosis.