Synthesis and characterization of cardo-based phosphorous–containing flame-retardant aromatic polyesters

Phosphorous-containing cardo polyesters were synthesized by interfacial polycondensation of phenylphosphonic dichloride with various bisphenols using a phase-transfer catalyst at ambient temperature. The structure of the synthesized polymers was confirmed using Fourier transform infrared and proton, carbon 13, and phosphorous 31 nuclear magnetic resonance spectroscopic techniques. The thermal properties of the polymers were studied by thermogravimetric analysis (TGA) and differential scanning calorimetry under nitrogen atmosphere. All the polyesters showed high thermal stability, the maximum decomposition temperature being in the range of 475–523°C. The TGA data showed that all the synthesized phosphorous-containing polyesters produce high char yield at 700°C due to the presence of phosphorous atom in the polymer chain and hence have good flame-retardant properties. The synthesized phosphorus-containing polyesters have tensile strength in the range of 38.2–48 MPa, and the percentage of elongation at breaks of 3.3–16.8. The flame retardancy of all synthesized polymers was investigated by limiting oxygen index (LOI) and vertical burning (UL-94) tests. The results showed that the synthesized polymers have excellent flame retardancy, that is, the polymer samples achieved an increased UL-94 rating and the LOI values were in the range of 28.5–34. Broido model has been used to study the thermal degradation kinetic parameters.

Giant Cell Lesions of Lungs: A Histopathological and Morphometric Study of Seven Autopsy Cases

INTRODUCTION

Macrophages undergo fusion to form multinucleated giant cells (MGC) in several pathologic conditions. The exact mechanism of their generation is still unclear. MGC are a common feature of granulomas that develop during various inflammatory reactions.

AIM

To study the histopathological features of giant cell lesions in lungs and correlate the characteristics of giant cells with other histopathological findings. Also, to determine the utility of morphometry to differentiate foreign body and Langhans MGC.

MATERIALS AND METHODS

Seven cases were analysed. Specimen of lungs was grossed, sectioned and processed. Routinely, tissue sections were stained by Haematoxylin and Eosin (H&E) stain. Polarizing microscopy and special stains were employed in selected cases. Granulomas and MGC were counted and measured. Several other parameters like location, distribution, type and number of MGC, associated predominant inflammatory component and nature of granulomas were analysed.

RESULTS

Five patterns of lesions were observed in seven cases. Aspiration pneumonia was seen in three cases (42.85%) and constituted the most common pattern. However, aspiration pneumonia as the only cause of MGC was seen in only one case (14.28%). Pulmonary tuberculosis and asteroid bodies constituted two cases (28.57%) each. Cryptococcal pneumonia and cholesterol clefts constituted one case (14.28%) each. Crypococci were demonstrated to be positively birefringent by polarized microscopy on Ziehl-Neelsen stained sections. Based on statistical analysis of morphometric data, a new index (NP index) was proposed to statistically categorize MGC into foreign body type and Langhans type. NP index value of ≤0.016 was found to be statistically significant (p<0.005) in foreign body MGC. It had high sensitivity and efficacy.

CONCLUSION

MGC may not be always associated with granulomas. The mechanisms that lead to the occurrence of MGC, independent of granuloma needs to be elucidated. Morphometry may serve as a useful aid. But a pathologist has to rely on the morphological details to categorize MGC.

Double Right Coronary Artery Originating from Separate Ostia: A Report of Two Cases

Context:

Coronary artery anomalies are uncommon and most are incidental findings. Double right coronary artery (RCA) is a very rare coronary artery anomaly.

Case Report:

We report two cases of double RCA incidentally found in electrocuted patients. Both cases showed double RCA arising from separate ostia. On microscopy, both right coronaries showed no significant pathology in the first case while in the second case, the posterior RCA showed features of obliterative arteritis.

Conclusion:

Although double coronary artery has been regarded as hemodynamically insignificant, it may be associated with atherosclerosis, acute coronary syndromes, and other anomalies. It is important to know the anatomic variants. Meticulous grossing and careful observation could unearth hidden anomalies.

Increase in upper tropospheric and lower stratospheric aerosol levels and its potential connection with Asian pollution

Satellite observations have shown that the Asian Summer Monsoon strongly influences the upper troposphere and lower stratosphere (UTLS) aerosol morphology through its role in the formation of the Asian Tropopause Aerosol Layer (ATAL). Stratospheric Aerosol and Gas Experiment II solar occultation and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) lidar observations show that summertime UTLS Aerosol Optical Depth (AOD) between 13 and 18 km over Asia has increased by three times since the late 1990s. Here we present the first in situ balloon measurements of aerosol backscatter in the UTLS from Western China, which confirm high aerosol levels observed by CALIPSO since 2006. Aircraft in situ measurements suggest that aerosols at lower altitudes of the ATAL are largely composed of carbonaceous and sulfate materials (carbon/sulfur elemental ratio ranging from 2 to 10). Back trajectory analysis from Cloud-Aerosol Lidar with Orthogonal Polarization observations indicates that deep convection over the Indian subcontinent supplies the ATAL through the transport of pollution into the UTLS. Time series of deep convection occurrence, carbon monoxide, aerosol, temperature, and relative humidity suggest that secondary aerosol formation and growth in a cold, moist convective environment could play an important role in the formation of ATAL. Finally, radiative calculations show that the ATAL layer has exerted a short-term regional forcing at the top of the atmosphere of -0.1 W/m² in the past 18 years.

KEY POINTS

Increase of summertime upper tropospheric aerosol levels over Asia since the 1990s Upper tropospheric enhancement also observed by in situ backscatter measurements Significant regional radiative forcing of -0.1 W/m².

Proline, glutamic acid and leucine-rich protein-1 is essential for optimal p53-mediated DNA damage response

Proline-, glutamic acid- and leucine-rich protein-1 (PELP1) is a scaffolding oncogenic protein that functions as a coregulator for a number of nuclear receptors. p53 is an important transcription factor and tumor suppressor that has a critical role in DNA damage response (DDR) including cell cycle arrest, repair or apoptosis. In this study, we found an unexpected role for PELP1 in modulating p53-mediated DDR. PELP1 is phosphorylated at Serine1033 by various DDR kinases like ataxia-telangiectasia mutated, ataxia telangiectasia and Rad3-related or DNAPKc and this phosphorylation of PELP1 is important for p53 coactivation functions. PELP1-depleted p53 (wild-type) breast cancer cells were less sensitive to various genotoxic agents including etoposide, camptothecin or γ-radiation. PELP1 interacts with p53, functions as p53-coactivator and is required for optimal activation of p53 target genes under genomic stress. Overall, these studies established a new role of PELP1 in DDRs and these findings will have future implications in our understanding of PELP1's role in cancer progression.

Endovascular coil occlusion of traumatic intradural aneurysm with presentation as carotid cavernous fistula

Carotid cavernous fistulae (CCF) are abnormal communication between cavernous segment of the internal carotid artery and cavernous sinus. These entities are usually encountered in 0.2-0.8% of patients with traumatic skull base fractures. Traumatic cerebral aneurysms are rare and account for less than 1% of intracranial aneurysms. CCF due to ruptured intradural traumatic aneurysm is very rare and difficult to treat by surgical methods. We present one such case of a 40-year-old man with post-traumatic CCF due to a ruptured intradural aneurysm successfully treated with endovascular embolization.

Abstract P5-11-02: Radiation instigates EMT, CSC self renewal and pluripotency signal transduction in non-targeted (bystander) ERa+ and triple-negative breast cancer cells

Ascertaining radiation-induced bystander response in non-targeted tumor cells, particularly on variables pertaining to resistance, relapse and tumor progression, may escort significant clinical implications. Accordingly, in this study, we investigated the radiation induced alterations in factors that drive the epithelial-to-mesenchymal transition (EMT), cancer stem cells (CSCs) self-renewal capacity and pluripotency maintenance in non-targeted breast (ERa+ MCF-7 and triple-negative MDA-MB-468) adenocarcinoma cells. Co-cultures of non-targeted breast cancer cells with irradiated (5Gy) counterparts for 24h were assessed for transcriptional regulation of 93 stem cell related molecules using QPCR profiling. Radiation-induced alterations in the expression of ABCG2, E-Cadherin, N-Cadherin, MYC, Nanog and SOX2 in bystander MCF-7 and MDA-MB-468 were assessed using western blot analysis. Radiation profoundly increased the transcriptional activation of stem-cell related molecules in distant bystander ERα+ MCF-7 (70 genes) and in triple-negative MDA-MB-468 (82 genes) cells. Interestingly, 62 of 70 genes activated in MCF-7 and 81 of 82 genes in MDA-MB-468 showed significant (&gt;2 fold) upregulation. Evidently, radiation induced 66 genes (&gt;2 fold, 58 genes) in bystander breast cancer cells independent of their hormone status. Consistently, immunoblotting revealed increase in the expression of ABCG2, N-Cadherin, MYC, Nanog and SOX2 in both MCF7 and MDA-MB-468. Together, these data demonstrates that radiation activates the EMT, CSCs self-renewal and pluripotency maintaining factors in non-targeted bystander cells and could thus play an instrumental role in breast cancer relapse and progression.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-11-02.

Abstract P6-09-05: Neem leaf extract, rich in nimbolide and azadirachtin targets radiation-induced stemness in surviving breast cancer cells

Recently, we have shown that the neem leaf extract (NLE) rich in Nimbolide and Azadirachtin exerted radiosensitization and alleviates tumor progression in varied solid tumor models. Accordingly, in this study, we investigated its potential in the regulation of radiation (IR)-induced stemness in surviving breast cancer (BCa) cells. Human breast adenocarcinoma (MCF-7) cells either mock-irradiated or exposed to IR (2Gy) with or without NLE (1, 10 or 100μg) pre-treatment (for 3h) and analyzed at 3h or 24h post-IR. Transcriptional alterations of 93 molecules that drive EMT, CSCs self-renewal capacity and pluripotency maintenance were analyzed using QPCR profiling. NANOG, SOX2, ABCG2, N-cadherin, E-cadherin and GSK3β expression was examined by immunoblotting. Radiation profoundly increased 67 stem-cell related molecules in surviving BCa cells. NLE exerted a dose-dependent (1μg, 23; 10μg, 51; 100μg, 64 genes) inhibition of IR-induced stem-cell related molecules. Second-phase observations at 24h post-IR revealed no recovery of NLE-inhibited transcription with complete inhibition of 12, 66 and 64 genes after 1, 10 and 100μg. Gene comparison analysis revealed both ‘dose-independent’ (20genes at 3h and 12genes at 24h) and ‘time-independent’ (6, 50 and 61 genes at 1μg, 10μg and 100μg respectively) inhibition. Interestingly, six genes (BMP4, CDH1, EGF3, FOXA2, GSK3β and HDAC2) showed both ‘time-and-dose-independent’ inhibition. Coherently, immunoblotting revealed a consistent regulation of IR-induced NANOG, SOX2, ABCG2, N-cadherin in the surviving BCa cells. Together these data demonstrate that NLE targets IR-induced stemness in surviving BCa cells and may thus serve as a potential “deliverable” to negate breast cancer relapse and progression.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-09-05.

Abstract P4-16-02: EF24 targets radiation-induced NFkB-dependent stemness in triple negative breast cancer cells

Prognosis of patients with late stage BCa still remains poor, mostly due to development of chemoradioresistance followed by tumor recurrence. Cancer stem cells (CSCs), with higher drug efflux capability, and other stem cell-like properties were proposed to be responsible for resistance, relapse and progression of BCa. We have shown that EF24 alleviates radiation (IR)-orchestrated NFkB mediated clonal expansion. Herein, we investigated the potential of EF24 in the regulation of IR-induced NFkB dependent stemness in triple negative breast cancer cells (TNBC). MDA-MB-231 cells exposed to mock-IR or IR (2Gy) with/without EF24 were examined for transcriptional alterations of 93 EMT, CSCs self-renewal, pluoripotentcy maintenance and other stem cell markers. NFkB (p50/p65) overexpression (with or without EF24) and RelA siRNA knockout (with IR) approach were used to delineate the role of IR-induced NFkB and the selective NFkB targeting of EF24 in this setting. Nanog, Sox-2, ABCG-2, N-Cadherin, POU5F1 and Myc expression was examined with immunoblotting. IR profoundly increased the transactivation of 86 stem-cell related molecules in TNBCs that are involved in cell survival. Interestingly, muting IR-induced NFkB attenuated 85 of those genes. Notably, EF24 suppressed identical 85 genes reproducing the inhibitory signature of NFkB muting. Coherently, activating NFkB induced 87 stem-cell related molecules in TNBC and of which 86 genes were completely suppressed with EF24. Alterations in the cellular expression levels of Nanog, Sox-2, ABCG-2, N-Cadherin, POU5F1 and Myc validates the potential of EF24 in mitigating IR-induced stemness in TNBC. Together these data demonstrates, at least in TNBC cells, IR-induced NFkB mediates increased stem-like characteristics and further imply that EF24 may alleviate stemness by selectively targeting IR-induced NFkB.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-16-02.

The relationship between anti-idursulfase antibody status and safety and efficacy outcomes in attenuated mucopolysaccharidosis II patients aged 5 years and older treated with intravenous idursulfase

In the pivotal phase II/III trial of idursulfase administered intravenously to treat mucopolysaccharidosis II, approximately half of the patients developed antibodies to idursulfase. This post-hoc analysis of data from the phase II/III trial and extension study examined the relationship between antibody status and outcomes. A total of 63 treatment-naïve patients received 0.5 mg/kg of intravenous idursulfase weekly for two years. Thirty-two patients (51%) were positive for anti-idursulfase IgG antibodies, 23 of whom (37%) became persistently positive. All patients who developed an antibody response did so by their scheduled Week 27 study visit. Positive antibody status appeared to have no statistically significant effect upon changes in six-minute walk test distance, percent predicted forced vital capacity, or liver and spleen volume. All patients showed significant decreases in urinary GAG levels, although the antibody positive group maintained somewhat higher urinary GAG levels than their antibody-negative counterparts at the end of study (138.7 vs. 94.7 μg/mg creatinine, p = 0.001). Antibody positivity was not associated with a higher event rate for serious adverse events. Among patients who had no prior infusion-related reactions, antibody positive patients were 2.3 times more likely to have a first infusion-related reaction than those who would remain negative (p = 0.017); the risk increased to 2.5 times more likely for those who were persistently positive (p = 0.009). These differences in risk disappeared among patients with a previous infusion-related reaction, likely because of preventive measures. A genotype analysis for the 36 patients with available data found that patients with nonsense or frameshift mutations may be more likely to develop antibodies, to experience infusion-related reactions, and to have a reduced uGAG response than those with missense mutations, suggesting the possibility that antibodies are not a driver of clinical outcomes but rather a marker for genotype.

Synthesis, spectral and thermal characterization of polyester derived from 1,1-bis(4-hydroxyphenyl)cyclohexane

A series of polyesters with pendant cyclohexane ring as a cardo group were synthesized by reacting 1,1-bis(4-hydroxyphenyl)cylcohexane (bisphenol-Z (BPZ)) with diacid chlorides. The molecular structures of the monomer and polymers were confirmed by spectral analyses. Thermal properties were studied using thermogravimetric analysis and differential scanning calorimetry. The thermogravimetric data revealed that the polymers are stable up to 190°C and start to degrade thereafter. The thermal stability initially increases with increase in spacer length and then decreases due to negative effects of the spacer. In the present study, Arrhenius, Broido and Horowitz–Metzger models have been used to calculate the degradation kinetic parameters.

Synthesis, spectral and thermal degradation kinetics of novolac resins derived from cardanol

The cardanol formaldehyde resin (CFR) has been synthesized by the condensation of cardanol with formaldehyde (ratio of 1:0.7) in the presence of oxalic acid catalyst. Synthesized CFR was epoxidized using epichlorohydrin (ECH) with 1:10 molar ratio. Cardanol was also directly epoxidized using ECH with the above-mentioned ratio. Synthesized resins have been characterized by Fourier-transform infrared and nuclear magnetic resonance spectroscopic analyses. Thermal properties have been studied by thermogravimetric analysis. Decomposition kinetics have been studied by various kinetic models of the synthesized compounds. In the present study, Horowitz–Metzger, Broido and Coats–Redfern models have been used to calculate the activation energy ( Ea), pre-exponential factor ( A) and rate constant ( K). Ea calculated from all the three models mentioned above was close to each other.

Pattern of refractive errors among the Nepalese population: a retrospective study

INTRODUCTION

Refractive errors are a major cause of visual impairment in the population.

PURPOSE

To find the pattern of refractive errors among patients evaluated in a tertiary care hospital in the western region of Nepal.

MATERIALS AND METHODS

The present hospital-based retrospective study was conducted in the Department of Ophthalmology of the Manipal Teaching Hospital, situated in Pokhara, Nepal. Patients who had refractive error of at least 0.5 D (dioptre) were included for the study.

RESULTS

During the study period, 15,410 patients attended the outpatient department and 10.8% of the patients were identified as having refractive error. The age of the patients in the present study ranged between 5 - 90 years. Myopia was the commonest refractive error followed by hypermetropia. There was no difference in the frequency of the type of refractive errors when they were defined using right the eye, the left eye or both the eyes. Males predominated among myopics and females predominated among hypermetropics. The majority of spherical errors was less than or equal to 2 D. Astigmatic power above 1D was rarely seen with hypermetropic astigmatism and was seen in around 13 % with myopic astigmatism. "Astigmatism against the rule" was more common than "astigmatism with the rule", irrespective of age.

CONCLUSION

Refractive errors progressively shift along myopia up to the third decade and change to hypermetropia till the seventh decade. Hyperopic shift in the refractive error in young adults should be well noted while planning any refractive surgery in younger patients with myopia.