A Conceptual Multi-Layer Framework for the Detection of Nighttime Pedestrian in Autonomous Vehicles Using Deep Reinforcement Learning

The major challenge faced by autonomous vehicles today is driving through busy roads without getting into an accident, especially with a pedestrian. To avoid collision with pedestrians, the vehicle requires the ability to communicate with a pedestrian to understand their actions. The most challenging task in research on computer vision is to detect pedestrian activities, especially at nighttime. The Advanced Driver-Assistance Systems (ADAS) has been developed for driving and parking support for vehicles to visualize sense, send and receive information from the environment but it lacks to detect nighttime pedestrian actions. This article proposes a framework based on Deep Reinforcement Learning (DRL) using Scale Invariant Faster Region-based Convolutional Neural Networks (SIFRCNN) technologies to efficiently detect pedestrian operations through which the vehicle, as agents train themselves from the environment and are forced to maximize the reward. The SIFRCNN has reduced the running time of detecting pedestrian operations from road images by incorporating Region Proposal Network (RPN) computation. Furthermore, we have used Reinforcement Learning (RL) for optimizing the Q-values and training itself to maximize the reward after getting the state from the SIFRCNN. In addition, the latest incarnation of SIFRCNN achieves near-real-time object detection from road images. The proposed SIFRCNN has been tested on KAIST, City Person, and Caltech datasets. The experimental results show an average improvement of 2.3% miss rate of pedestrian detection at nighttime compared to the other CNN-based pedestrian detectors.

Biological screening and docking studies of unique hybrids synthesized by conventional versus microwave assisted techniques

Purpose: To carry out the synthesis of various hybrids of 1,2,4-triazole in search of potential therapeutic enzyme inhibitory agents, and carry out docking and bovine serum albumin (BSA) binding studies on docking and bovine serum albumin (BSA) binding studies on the hybrids. Methods: The target compounds were synthesized by following a multistep protocol. Compound 1 was synthesized from 4-methoxybenzenesulfonyl chloride (a) and ethyl isonipecotate (b). Compound 1 was refluxed with hydrazine to synthesize compound 2, which was converted to compound 3 through two consecutive steps. Compound 4 and different amines (5a-5i), were utilized to synthesize an array of electrophiles (6a-6i). A series of 1,2,4-triazole hybrids (7a-7i) were synthesized at room temperature by stirring together 3 and 6a-6i. The final structures of 7a-7i were elucidated through 1H-NMR, 13C-NMR and EI-MS spectroscopy. The BSA binding studies were performed by fluorometric titration. Furthermore, antioxidant and enzyme inhibition activities were determined colorimetrically. Results: Compound 7d was the most active antioxidant agent, compared to butylated hydroxyanisole (BHA), while compounds 7d, 7e, 7f, 7g and 7i proved to be potent urease inhibitors with half-maximal inhibitory concentration (IC50) values of 19.5 ± 0.12, 21.1 ± 0.68, 18.2 ± 0.78, 19.9 ± 0.77 and 17.9 ± 0.10 µM, respectively, compared to thiourea with an IC50 of 24.3 ± 0.24 µM. Compounds 7a, 7b, 7d, and 7e exhibited high butyrylcholinesterase inhibition potential, compared to eserine. Conclusion: The synthesized compounds require studies further as potential therapeutic enzyme inhibitory agents in view of their urease inhibition as well as antioxidant activity.

Optimization of bio-cement production from cement kiln dust using microalgae

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CKD with microalgae sp. Chlorella kessleri is investigated for maximum bio-cement yields.

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A predictive quadratic model was developed for CaCO₃ yield with R² value of c.a. 92%.

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Low temperature and high pH were found to be important parameters in RSM study.

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Under optimal set, a maximum of 96% Ca was extracted experimentally from CKD.

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FTIR, XRD and EDS analysis confirmed the produced bio-cement compound.

The main aim of this study was to maximize bio-cement (CaCO₃) production through a waste feedstock of cement kiln dust (CKD) as a source of calcium by deployment of microalgae sp. Chlorella kessleri. The effect of process parameters such as temperature, pH and time-intervals of microalgae cultivation, were set as criteria that ultimately subscribe to a process of optimization. In this regard, a single factor experiments integrated with response surface methodology (RSM) via central composite design (CCD) was considered. A quadratic model was developed to predict the maximum CaCO₃ yield. A ceiling of 25.18 g CaCO₃ yield was obtained at an optimal set of 23 °C, pH of 10.63 and day-9 of microalgae culture. Under these optimized conditions, maximum 96% calcium was extracted from CKD. FTIR, XRD and EDS analyses were conducted to characterize the CaCO₃ precipitates. Compressive modes of mechanical testing seemed to hold conventional cement complimented by CaCO₃ co-presence markedly superior to mere cement performance as far as compressive strength is concerned. The latter criterion exhibited further increase in correspondence with rise in cement to bio-cement ratio. This investigative endeavour at hand offers a simple pivotal platform on the basis of which a scale-up of microalgae-infested bio-cement production might be facilitated in conjunction with the added benefit of alleviation in environmental pollution through cement waste utilization.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

[Association of fallopian tube cancer and polymyositis. Apropos of 1 case]

A 51-year-old woman consulted for pelvic pain, metrorrhagia and leukorrhea. Physical examination revealed a renitent and mobile mass in the pelvis. A right lateral uterine mass with hydroxalpinx was found at ultrasonography. Pathology examination of the right annexectomy specimen provided the definitive diagnosis: fallopian tube cancer with polymyositis. No residual tumor was found at total hysterectomy with total bilateral annexectomy. The patient was lost to follow-up for three years without complementary treatment then consulted later for functional disability of the upper then lower limbs with myalgia, swallowing disorders and left supraclavian node enlargement resulting from pelvic relapse of the right fallopian tube adenocarcinoma and left supraclavian metastasis with paraneoplastic polymositis. The patient was given 6 courses of chemotherapy with radiotherapy (45 Gy) centered on the left clavian region. The patient exhibited a spectacular response, and remains in complete remission 50 months after diagnosis. The association of a fallopian tube tumor with polymyositis is exceptional, requiring rapid anticancer treatment effective against the cancer and the paraneoplastic polymyositis.

[Safety of meningococcal A and C vaccine. Data from the Spanish drug surveillance system. Meningococcal Vaccine Research Group of the Spanish System of Drug Surveillance]

OBJECTIVE

Data on meningococcal vaccines safety are scanty. In 1997 several vaccination campaign took place in Spain. Thus, this situation was used to improve our knowledge about the safety profile of this vaccine.

METHODS

An inquiry was carried out to the Regional Centers of the Spanish Pharmacovigilance System to know the number of vaccinated people and the type and number of suspected cases of adverse reactions.

RESULTS

There were 133 identified cases of suspected adverse reactions associated with meningococcal A and C vaccine until June 1st, 1998. Most of them affected the skin (25,3%) or nervous system (similar proportion). Those of allergic reactions accounted for 35,2%. Two cases were considered as severe, although they were resolved without secuelae.

CONCLUSIONS

Serious risks were not detected. The Spanish Pharmacosurveillance System as an epidemiological surveillance resource has been useful to know the safety problems associated with antimeningococcal vaccine in the community.

Immunohistochemical analysis of metallothionein in astrocytic tumors in relation to tumor grade, proliferative potential, and survival

BACKGROUND

Metallothionein (MT) is the name for a family of predominantly intracellular protein thiol compounds involved in anticancer drug resistance. For certain tumors, MT is related to grade of tumor malignancy and prognosis. The authors evaluated the expression of MT in 114 astrocytic tumors in relation to the proliferative potential of tumors and the survival of patients.

METHODS

Paraffin embedded tissue sections were stained with monoclonal anti-metallothionein and MIB-1 Ki-67 antibodies by avidin-biotin complex immunohistochemistry.

RESULTS

MT expression was observed in 2 of 6 pilocytic astrocytomas, in 10 of 24 Grade 2 astrocytomas, in 16 of 25 anaplastic astrocytomas, and in 47 of 59 glioblastomas. In addition to the tumor cells, microvascular endothelial proliferation and smooth muscle of tumor vessel walls were frequently MT positive. The glioblastomas had a significantly higher percentage of MT positive cells compared with low grade (P < 0.0001) and anaplastic (P < 0.04) astrocytomas. MT expression in astrocytomas had no correlation with tumor recurrence. The mean Ki-67 labeling index (LI) was significantly higher in the high grade (3-4) compared with the low grade (1-2) astrocytomas. MT positive astrocytic tumors had statistically significantly higher mean Ki-67 LI compared with MT negative tumors, irrespective of histologic grade. Although the levels of MT and Ki-67 LI varied in individual tumors, the mean Ki-67 LI increased in parallel to the increasing MT staining grade, and this difference attained statistical significance only for glioblastoma. MT positive anaplastic astrocytoma and glioblastoma patients did not survive as long as the MT negative patients, although this difference attained statistical significance only for anaplastic astrocytoma.

CONCLUSIONS

The current study suggests that MT might play a significant role in the growth of astrocytic tumors, with an acquired enhanced ability to produce MT as the malignant potential of a tumor increases.

Role of UEV-1A, a homologue of the tumor suppressor protein TSG101, in protection from DNA damage

The open reading frame YGL087c in the budding yeast Saccharomyces cerevisiae genome encodes a polypeptide highly similar to the human UEV (ubiquitin-conjugating E2 enzyme variant) proteins, which have been proposed to belong to a family of putative dominant negative ubiquitin regulators. Deletion of the YGL087c open reading frame yields viable cells which are sensitive to UV irradiation or methyl methanesulfonate, but not to hydroxyurea. This phenotype is reminiscent of that of rad mutants and suggests that the YGL087c-encoded protein functions in a process related to tolerance to DNA damage. We also show that the mutant phenotype is fully complemented by expression of the human UEV-1A cDNA and we propose that UEV-1 proteins could also have a role in protecting higher eukaryotic cells from DNA damaging agents.

Immunohistochemical analysis of progesterone receptor and Ki-67 labeling index in astrocytic tumors

BACKGROUND

Intracranial tumors such as meningiomas express steroid hormone receptors but little is known regarding progesterone receptor (PR) in astrocytic tumors. The authors evaluated expression of PR in 86 astrocytic tumors in relation to tumor proliferative potential.

METHODS

Paraffin embedded tumor sections were stained with polyclonal antiprogesterone antibody by the peroxidase-antiperoxidase method and with monoclonal MIB-1-Ki-67 antibody by avidin-biotin complex immunohistochemistry.

RESULTS

Sixty-three of the 86 astrocytic tumors (73%) showed positive PR immunoreactivity. PR expression was observed in 4 of 9 pilocytic astrocytomas, 13 of 24 Grade 2 astrocytomas, 15 of 20 anaplastic astrocytomas, and 31 of 33 glioblastomas. In addition to the tumor cells, cells of microvascular endothelial proliferation and the smooth muscle of tumor vessel walls were frequently PR positive. Glioblastomas had a significantly higher percentage of PR positive cells compared with anaplastic (P < 0.0008) and low grade (P < 0.0001) astrocytomas. Patients with PR positive astrocytomas were of an older age than patients with PR negative astrocytomas (48.71 +/- 21.95 years vs. 37.09 +/- 24.69 years; P < 0.04). The mean Ki-67 labeling index (LI) was significantly higher in the high grade (3-4) astrocytomas compared with low grade (1-2) astrocytomas (P < 0.0001). PR positive astrocytic tumors had higher Ki-67 LI than PR negative tumors. PR expression was not correlated with tumor recurrence and patient survival.

CONCLUSIONS

The current study suggests that PR in the astrocytic tumors correlates with histologic grade and PR may participate in the growth of these tumors and tumor angiogenesis. The measurement of PR in these tumors may indirectly represent tumor growth potential.

Effect of tumor necrosis factor-alpha on the permeability of bovine brain microvessel endothelial cell monolayers

The administration of chemotherapy to patients with tumors of the central nervous system is often blocked by the blood-brain barrier. Tumor necrosis factor-alpha (TNF-alpha) is a cytokine that promotes vascular permeability in addition to its pro-inflammatory effects. However, no direct evidence exists as to whether TNF-alpha may increase permeability of the BBB. We evaluated the effect of TNF-alpha on the transport of cisplatin (CDDP) or high molecular weight dextran labeled with fluorescein isothiocyanate (FITC-dextran) across bovine brain microvessel endothelial cell (BMEC) monolayers that was conducted on side-by-side diffusion chambers in vitro. The permeability coefficient for the transport of CDDP across the untreated monolayer was 3.80 x 10(-5) cm sec-1 at 30 minutes. After treating the BMEC monolayer with TNF-alpha (50 U ml-1 and 500 U ml-1) for 36 hours, the PC of CDDP increased significantly to 8.94 x 10(-5), and 14.43 x 10(-5) cm sec-1 respectively (p < 0.01). TNF-alpha had no effect on the transport of FITC-dextran across the BMEC monolayers. Electron microscopy showed that the tight junctions between the BMECs persisted even after treatment with TNF-alpha, whereas they had been partially disrupted following exposure to mannitol, 1600 mOsm kg-1. TNF-alpha selectively promoted the in vitro permeability of the blood-brain barrier to CDDP without disrupting tight junctions. This system could be used as a model for experimental studies of chemotherapy. Findings suggested that the combined administration of TNF-alpha and CDDP may be clinically useful.

Sequence analysis of a 12 801 bp fragment of the left arm of yeast chromosome XV containing a putative 6-phosphofructo-2-kinase gene, a gene for a possible glycophospholipid-anchored surface protein and six other open reading frames

The DNA sequence of a 12,801 bp fragment located near the left telomere of chromosome XV has been determined. Sequence analysis reveals eight open reading frames (ORFs) encoding polypeptides larger than 100 residues. ORFs AOE129 and AOAA121 are in opposite strands and they overlap at their 3' ends. AOE397 has similarity with phosphofructokinase genes from other organisms and may code for a second 6-phosphofructo-2-kinase of Saccharomyces cerevisiae. Sequence of AOA471 shows significant similarity with yeast genes coding for glycophospholipid-containing proteins. AOD1341 would code for a 1341 amino acids long protein with a predicted ATP/GTP-binding site and a transmembrane domain.

Sequence analysis of a 13.4 kbp fragment from the left arm of chromosome XV reveals a malate dehydrogenase gene, a putative Ser/Thr protein kinase, the ribosomal L25 gene and four new open reading frames

A 13421 bp fragment located near the left telomere of chromosome XV (cosmid pEOA461) has been sequenced. Seven non-overlapping open reading frames (ORFs) encoding polypeptides longer than 100 residues have been found (AOB859, AOC184, AOE375, AOX142i, AOE423, AOA476 and AOE433). An additional ORF (AOE131) is found within AOA476. Three of them (AOC184, AOA476 and AOE433) show no remarkable identity with proteins deposited in the data banks. ORF AOB859 is quite similar to a hypothetical yeast protein of similar size located in chromosome VI, particularly within the C-terminal half. AOE375 encodes a new member of the glycogen synthase kinase-3 subfamily of Ser/Thr protein kinases. AOX142i is the gene encoding the previously described ribosomal protein L25. AOE423 codes for a protein virtually identical to the MDH2 malate dehydrogenase isozyme. However, our DNA sequence shows a single one-base insertion upstream of the reported initiating codon. This would produce a larger ORF by extending 46 residues the N-terminus of the protein. The existence of this insertion has been confirmed in three different yeast strains, including FY1679.

Endothelin receptor in microvessels isolated from human meningiomas: quantification with radioluminography

1. We characterized specific 125I-endothelin-1 (125I-ET-1) binding sites in microvessels isolated from human meningiomas, using an in vitro quantitative receptor autoradiographic technique coupled to a radioluminographic imaging plate system. 2. This newly developed and highly sensitive method revealed high-affinity ET receptors present in pellet sections of the microvessels from all the meningiomas studied, regardless of histological subtypes (dissociation constant, 1.2 +/- 0.3 nM; maximum binding capacity, 185 +/- 56 fmol/mg; means +/- SE for nine tumors). 3. In five cases of meningiomas, ET-3 competed for 125I-ET-1 binding to microvessels from those tumors with a low affinity [50% inhibiting concentration (IC50) of 1.6 +/- 0.4 x 10(-6) M], and a selective ETB receptor agonist, sarafotoxin S6c, up to 10(-6) M, did not displace ET binding from the sections. 4. In the sections of microvessels from four other tumors, biphasic competition curves were obtained in the case of incubation in the presence of increasing concentrations of ET-3, with an IC50 of 1.1 +/- 0.2 x 10(-9) M for the high-affinity component and 1.6 +/- 0.3 x 10(-6) M for the low-affinity component, respectively. In addition, S6c competed for ET binding to those sections (IC50 = 2.3 +/- 0.2 x 10(-10) M) and 10(-6) M S6c displaced 30% of the control, corresponding to the high-affinity component of competition curves obtained in the presence of ET-3. 5. Our results suggest that (a) capillaries in human meningiomas express a large number of high-affinity ETA (non-ETB) receptors with a small proportion of ETB receptors, and (b) ET may have a role in neovascularization, tumor blood flow, and/or function of the blood-tumor barrier in meningioma tissues by interacting with specific receptors present on the surface of the endothelium.

Immunohistochemical expression of the estrogen receptor-related antigen (ER-D5) in human intracranial tumors

BACKGROUND

Expression of the estrogen receptor-related antigen (ER-D5) has been reported in some normal and neoplastic tissues. The authors evaluated the expression of ER-D5 in 143 intracranial tumors of different histologic types.

METHODS

Formalin fixed, paraffin embedded tumor sections were stained with the monoclonal D5 antibody by avidin-biotin complex immunohistochemistry.

RESULTS

Eighty-eight (62%) of the 143 brain tumors showed positive ER-D5 immunoreactivity. ER-D5 expression was observed in 9/30 low grade astrocytomas, in 6/13 anaplastic astrocytomas, in 16/27 glioblastomas, in 2/5 ependymomas, in 5/8 medulloblastomas, in 10/15 meningiomas, in 20/23 schwannomas, in 11/11 hemangioblastomas, in 9/9 germ cell tumors, in 0/2 oligodendrogliomas, and in 17/28 pediatric and childhood brain tumors. The mean percentage of ER-D5-positive cells varied in different tumor types, was lowest in the meningotheliomatous meningiomas, and was highest in the hemangioblastomas. ER-D5 immunoreactivity was also observed in the microvascular endothelial proliferations and in tumor blood vessels. ER-D5 expression in tumors was not related to the overall tumor grades, but a statistically significant higher percentage of ER-D5-positive cells was noted in the glioblastomas compared with the low grade astrocytomas (P < 0.05) and in the combined high grade tumors compared with the low grade tumors (P < 0.005) if vascular-origin tumor hemangioblastomas are considered a separate entity from other brain tumors.

CONCLUSION

The current study suggests that the ER-D5 antigen may participate in the growth of the intracranial tumors and tumor angiogenesis. ER-D5 in embryonal and germ cell brain tumors suggests that ER-D5 may be a developmentally regulated protein.

Expression of the small heat shock protein (hsp) 27 in human astrocytomas correlates with histologic grades and tumor growth fractions

1. Cellular expression and distribution of the stress response small heat shock protein 27 (hsp27) in 39 high-grade astrocytomas (27 glioblastoma multiformes, 12 anaplastic astrocytomas) and in 27 low-grade astrocytomas (grade I-II) were analyzed immunohistochemically. 2. The correlation between hsp27 expression and tumor growth fractions of the astrocytomas was examined following Ki-67 immunostaining. 3. The hsp27 staining was cell cytoplasmic. The hsp27 immunopositive rate was significantly higher in high-grade astrocytomas; the rates was 74% for glioblastomas, 58% for anaplastic astrocytomas, and 37% for low-grade astrocytomas. The small and large tumor cells, especially in glioblastomas, multinucleated tumor giant cells, tumor cells in the pseudopalisading and necrotic areas, cells of the microvascular endothelial proliferations, and tumor vascular smooth muscles were usually hsp27 positive. The mean percentage of hsp27-positive cells was significantly higher in the glioblastomas alone and in the combined high-grade astrocytomas, compared to the low-grade, and in recurrent rather than in primary high-grade astrocytomas. 4. The high-grade astrocytomas had a highly statistical significant Ki-67 labeling index. The Ki-67 labeling indices were significantly higher in the hsp27-positive than the hsp27-negative astrocytomas, irrespective of the histological grade. In the high-grade astrocytomas with a Ki-67 labeling index of five and above, 81% of those tumors were hsp27 positive. 5. Thus, a large number of human astrocytomas express hsp27, and hsp27 expression correlates with histological grades of astrocytoma and with tumor growth fractions. This being the case, hsp27 is likely to have a role in the growth of human astrocytomas.

Enhanced expression of an endothelin ETA receptor in capillaries from human glioblastoma: a quantitative receptor autoradiographic analysis using a radioluminographic imaging plate system

We identified and characterized 125I-endothelin-1 (125I-ET-1) binding sites in tumor capillaries isolated from human glioblastomas, using the quantitative receptor autoradiographic technique with pellet sections. Quantification was done using the computerized radioluminographic imaging plate system. High-affinity ET receptors were localized in capillaries from glioblastomas and the surrounding brain tissues (KD = 4.7 +/- 1.0 x 10(-10) and 1.6 +/- 0.3 x 10(-10) M, respectively; Bmax = 161 +/- 38 and 140 +/- 37 fmol/mg, respectively; mean +/- SEM, n = 5). BQ-123, a selective antagonist for the ETA receptor, potently competed for 125I-ET-1 binding to sections of the microvessels with IC50 values of 5.1 +/- 0.3 and 5.1 +/- 1.5 nM, and 10(-6) M BQ-123 displaced 84 and 58% of ET binding to capillaries from tumors and brains, respectively. In addition, competition curves obtained in the presence of increasing concentrations of ET-3 showed two components (IC50 = 5.7 +/- 2.5 x 10(-10) and 1.4 +/- 0.2 x 10(-6) M for tumor microvessels, 1.8 +/- 0.6 x 10(-10) and 1.1 +/- 0.3 x 10(-6) M for brain microvessels, respectively). Our results indicate that (a) the method we used is simple and highly sensitive for detecting and characterizing various receptors in tumor capillaries, especially in the case of a sparse specimen, and (b) capillaries in glioblastomas express specific high-affinity ET binding sites, candidates for biologically active ET receptors, which predominantly belong to the ETA subtype.

Immunohistochemical study of estrogen receptor-related antigen, progesterone and estrogen receptors in human intracranial meningiomas

BACKGROUND

The estrogen receptor-related antigen (ER-D5) is a serine phosphoprotein associated with the estrogen receptor that is present only in estrogen receptor- (ER) positive tissues and has no relation with progesterone receptor (PR). This study was performed to evaluate whether immunostaining of these proteins correlated with the proliferative potential of meningiomas as evaluated by clinicopathologic features.

METHODS

Immunohistochemical staining of ER-D5, ER, and PR were performed on paraffin embedded sections of meningiomas from 34 patients.

RESULTS

Twenty two (64.7%) of the 34 meningiomas tested were positive for ER-D5 with exclusively cytoplasmic immunostaining. All of the cases were positive for PR but not for ER. Progesterone receptors in meningiomas were cytoplasmic and/or nuclear. The correlation of ER-D5 reactivity with histologic subtypes showed positivity rates for meningotheliomatous meningiomas of 71.4%, fibroblastic 41.7%, transitional 80%, anaplastic 100% and hemangiopericytic 100%. ER-D5 positivity rates in primary and recurrent meningiomas were 59.3% and 85.7%, respectively. Normal arachnoid tissue was positive for PR but negative for ER-D5 and ER. Patient age and sex has no significant influence on the positivity rate of meningiomas. The mean number of AgNORs in ER-D5-positive and -negative meningiomas had no statistical significance.

CONCLUSIONS

This study suggests that ER-D5 has some role in the growth of the meningioma and that the expression of ER-D5 in human meningioma is independent of ER as it is in breast cancer. The localization of PR in the meningioma cells indicate that at least some of these cells are functionally active.

A selective endothelin ETA antagonist, BQ-123, inhibits 125I-endothelin-1 (125I-ET-1) binding to human meningiomas and antagonizes ET-1-induced proliferation of meningioma cells

1. We studied the effects of BQ-123, a selective ETA receptor antagonist, on 125I-endothelin-1 (125I-ET-1) binding to cell surface receptors in surgically exercised human meningiomas and on ET-1-induced DNA synthesis in cultured human meningioma cells in vitro, using a quantitative receptor autoradiographic technique with radioluminography and 3H-thymidine incorporation, respectively. 2. All of the human meningiomas expressed high-affinity binding sites for 125I-ET-1, regardless of differences in histological subtypes (Kd = 2.6 +/- 0.2 nM, Bmax = 374 +/- 93 fmol/mg; mean +/- SE; n = 9). 3. BQ-123 competed for 125I-ET-1 binding to sections of meningiomas with IC50S of 3.2 +/- 0.9 x 10(-7) M, and 10(-4) M BQ-123 displaced 80% of the binding. 4. ET-1 significantly stimulated DNA synthesis in cultured human meningioma cells, up to 170% of the basal level in the presence of 10(-9) M ET-1. BQ-123 inhibited ET-1 (10(-9) M)-induced DNA synthesis in meningioma cells, in a dose-dependent manner, and 10(-5) M BQ-123 reduced it to 120% of the basal level. 5. The number of meningioma cells determined after 4 days in culture was dose dependently increased in the presence of ET-1 (10(-9) and 10(-7) M). The growth rate of meningioma cells, incubated with 10(-9) M ET-1, was reduced by 50% in the presence of 10(-7) M BQ-123.(ABSTRACT TRUNCATED AT 250 WORDS)

Biphasic effects of suramin on 125I-epidermal growth factor binding to human meningiomas

1. We studied the effects of suramin, a nonspecific growth factor antagonist, on epidermal growth factor (EGF) binding to cell surface receptors in surgically excised human meningiomas, using quantitative receptor autoradiographic methods with radioluminography. 2. High concentrations (10(-4) - 10(-2) M) of suramin inhibited 125I-EGF binding to meningioma sections with IC50's of 3.2 +/- 0.4 x 10(-4) M, whereas lower concentrations (10(-5) - 10(-4) M) of the drug significantly enhanced EGF binding to the tumor. Scatchard analysis of EGF binding profile revealed significant increases in binding affinity following incubation in the presence of 5 x 10(-5) M suramin, without significant alterations in maximal binding capacity. 3. The addition of 10(-3) M suramin to the incubation buffer rapidly dissociated 125I-EGF previously bound to meningioma tissues as a function of time (dissociation half-life, T1/2 = 12.4 min). 4. Preincubation in the presence of 5 x 10(-5) M suramin resulted in significant increases in the subsequent binding of 125I-EGF to meningiomas, compared to findings in the control. 5. Our data indicate that (a) suramin exerts biphasic effects on EGF binding to the tissue sections of meningiomas in vitro, depending on the concentration of the drug; and (b) low concentrations of suramin enhance the affinity of the EGF receptor in the tumor sections, probably by interacting with the EGF receptor molecule rather than with the EGF peptide. 6. The functional role of increased EGF receptor affinity in meningioma sections in the presence of lower concentrations of suramin remains to be determined.

Abnormalities of chromosome 11Q in three cases of acute myeloid leukemia

The haematological findings and case history of 3 patients with the association of acute myeloid leukemia and translocation involving the long arm of chromosome no. 11 are presented. The recipient chromosome for the translocated material from chromosome 11 differs in all the three cases being namely chromosomes 1, 10 and 17.