Biocompatible polysaccharide fabricated graphene oxide nanoparticles: A versatile nanodrug carrier to deliver κ- carrageenan against cancer cells

A graphene oxide mediated hybrid nano system for pH stimuli-responsive and in vitro drug delivery targeted for cancer was described in this study. Graphene oxide (GO) functionalized Chitosan (CS) mediated nanocarrier capped with xyloglucan (XG) was fabricated with and without Kappa carrageenan (κ-C) from red seaweed, Kappaphycus alverzii, as an active drug. FTIR, EDAX, XPS, XRD, SEM and HR-TEM studies were carried out for GO-CS-XG nanocarrier loaded with and without active drugs to understand the physicochemical properties. XPS (C1s, N1s and O1s) confirmed the fabrications of XG and functionalization of GO by CS via the binding energies at 284.2 eV, 399.4 eV and 531.3 eV, respectively. The amount of drug loaded in vitro was 0.422 mg/mL. The GO-CS-XG nanocarrier showed a cumulative drug release of 77 % at acidic pH 5.3. In contrast to physiological conditions, the release rate of κ-C from the GO-CS-XG nanocarrier was considerably higher in the acidic condition. Thus, a pH stimuli-responsive anticancer drug release was successfully achieved with the GO-CS-XG-κ-C nanocarrier system for the first time. The drug release mechanism was carried out using various kinetic models that showed a mixed release behavior depending on concentration and diffusion/swelling mechanism. The best-fitting model which supports our release mechanism are zero order, first order and Higuchi models. GO-CS-XG and κ-C loaded nanocarrier biocompatibility were determined by in vitro hemolysis and membrane stabilization studies. MCF-7 and U937 cancer cell lines were used to study the cytotoxicity of the nanocarrier by MTT assay, which indicates excellent cytocompatibility. These findings support the versatile use of a green renewable biocompatible GO-CS-XG nanocarrier as targeted drug delivery and potential anticancer agent for therapeutic purposes.

Enhancement of Thermal Behaviour of Flax with a Ramie Fibre-Reinforced Polymer Composite

Plant-derived fibres, called lignocellulosic fibres, are a natural alternative to synthetic fibres in polymer composite reinforcement. Utilizing renewable resources, such as fibre-reinforced polymeric composites made from plant and animal sources, has become a crucial design requirement for developing and producing parts for all industrial goods. Natural-fibre-based composites are used for door panels, trays, glove boxes, etc. This study involves developing and thermal analysing a flax fibre reinforced with phenol-formaldehyde resin hybridization with ramie fibre by way of a vacuum infusion process. As per ASTM Standard, eight different sequences were fabricated and thermally characterized. In the present study, three stages of weight loss (%) are shown by the thermogravimetric analysis (TGA). The sample loses less weight during the first stage, more during the second, and more during the third. The sample's overall maximum temperature was recorded at 630 °C. It was discovered that sample D (80.1 °C) had the highest heat deflection temperature, and sample B had the lowest (86.0 °C). Sample C had a low thermal expansion coefficient, while sample G had a high thermal expansion coefficient. Sample E had the highest thermal conductivity, measured at 0.213 W/mK, whereas sample A had the lowest conductivity, at 0.182 W/mK. From the present study, it was found that sample H had better thermal characteristics. The result of the present investigation would generate thermal data regarding hybrid ramie and flax composites, which would be helpful for researchers and practitioners involved in the field of biocomposites.

Experimental Investigation of Bi-Directional Flax with Ramie Fibre-Reinforced Phenol-Formaldehyde Hybrid Composites

Modern research focuses on natural, green, and sustainable materials that can be used to replace conventional materials. Because of their beneficial qualities, natural fibre composites are being thoroughly researched. This research focuses on the development of a flax fibre reinforced with phenol-formaldehyde resin hybridization with ramie fibre through a vacuum infusion process. Eight different sequences were fabricated using a core-sheath structure and were mechanically characterized as per ASTM standards. The fabrication technique influences the adhesion of the matrix with reinforcement. The results also reveal that composite having ramie as a sheath layer and flax as a core delivers good mechanical characteristics compared to vice versa. The laminate H exhibited highest mechanical properties among all the eight laminates produced for this study. It exhibited a tensile strength of 54 MPa, tensile modulus of 0.98 Gpa, elongation of 7.1%, flexural strength of 143 Mpa, and compressive strength of 63.65 Mpa. The stress strain curves revealed that all the laminates exhibited ductile behaviour before failing during the tensile test and flexural test, respectively. The stacking sequence of the laminate H influenced the mechanical properties exhibited by it and its counterparts. A morphological study was carried out to analyse the failure surfaces. Morphological analysis exhibited few defects in the laminate after the tests. The composites developed delivers better mechanical properties than commercial composites available on the market, which can be used in lightweight structural applications.

Energy aware data harvesting strategy based on optimal node selection for extended network lifecycle in smart dust

Smart Dust environment face additional challenges as a result of the use of movable Smart Dust basestation(BS), despite its benefits. The main point of contention is the BS positioning updates to the smart dust nodes. Each smart object ought to be aware of the BS location so that it can send its data to the BS. According to the prevailing Flooding approach, the moveable BS must continuously distribute its location throughout the network in order to inform smart dust nodes about the BS location. In every case, visit positioning upgrades from the BS can result in maximal power usage as well as enhanced network breakdowns. Different sorts of routing architectures can be used to reduce BS position updating. A routing strategy based on the movable BS is successful if it preserves the network network’s power consumption and latencies to a minimum. The study’s main goal is to develop an energy-efficient routing mechanism focused on adaptive movable BS modification. In the Smart Dust Head (SDH) establishing the inferred surroundings, the most latest movable BS location will be preserved. As a result, rather than soliciting SDH in the environment, the location of the BS is propagated to the smart dust nodes located at the sectors in integrated networking. By transmitting request information to the nearest sector, the remaining SDH can find the most current BS location. The message’s recipient is determined based on the information gathered. The best fuzzy related clustering algorithm will be used to accomplish this. The Enhanced Oppositional grey wolf optimization (EOGWO) methodology can be used to perform the improvement. Optimum network throughput, low latency, and other metrics are used to assess performance. To enhance productivity, the findings will be analyzed and compared to previous routing methodologies.

Energy Efficient Secured CH Clustered Routing (E2SCR) in smart dust network

A basic need in smart dust network is to accomplish energy proficiency during routing as sensor nodes have rare energy asset. Node’s mobility in smart dust represents a challenge to intend energy proficient routing algorithm. Clustering accomplishes energy effectiveness by diminishing association complication aloft of network is comparative to quantity of moveable smart dust nodes in network. This research methodology proposes novel Energy Efficient Secured CH Clustered Routing (E2SCR) in Smart Dust tactic. A smart dust node is chosen as cluster head in event that it has high superfluous energy, better communication range and low mobility. Energy responsive (ER) selection method and Maximal Nodal Superfluous Energy assessment method combined with this method to enhance energy conception during routing. Simulation results demonstrate that proposed clustering and routing algorithm is unique and energy efficient smart dust network.

POS0286 CAN PATIENTS WITH CONTROLLED RA RECEIVING ANY CLASS OF TARGETED THERAPY WITH METHOTREXATE (MTX) SUSTAIN DISEASE CONTROL AFTER TAPERING MTX? A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Patients with RA frequently struggle with intolerance of MTX and adherence to MTX remains highly variable. Guidelines conditionally recommend the tapering of MTX before tapering biologic (b)DMARDs, but acknowledge there is an absence of direct evidence. Prior reviews on this topic have focused on tapering of MTX from combination treatment with TNF-inhibitors(i) only1. There have been no updated reviews addressing MTX tapering from other targeted therapies such as IL6-i or JAK-i, nor has there been a systematic review addressing this question.

Objectives

To determine the feasibility of tapering MTX to targeted therapy (bDMARDs or JAKi) alone in patients whose RA is controlled (LDA or remission).

Methods

A systematic literature search combing MeSH terms and keywords was conducted in Medline, Embase and Cochrane Library for studies reporting remission outcomes after tapering MTX from targeted therapies in RA. Non-English and animal studies were excluded. Meta-analyses were conducted using random effects models. Forest and funnel plots were created and heterogeneity was calculated.

Results

Our search identified 5762 citations. After removal of duplicates and screening title/abstract using the COVIDENCE platform, 504 full-text articles were reviewed. Of the 10 articles meeting our inclusion criteria of tapering MTX to monotherapy with a targeted therapy, 3 studies tapered to etanercept, 3 to tocilizumab, 1 to tofacitinib, 1 to certolizumab pegol, 1 to adalimumab and 1 to abatacept monotherapy. Nine studies were RCTs and one was a long-term extension study (LTE) (Table 1). Disease duration was longer in 7 studies (6-11 years) and early in 3 studies (1-9 months). The MTX tapering strategy was gradual in 2 and rapid in 8 studies. Follow-up ranged from 3 -18 months in RCTs, and up to 3 years in the LTE. Studies reporting outcomes up to 1 year after tapering had remission rates ranging 48-76%, but this dropped to 40% in one study reporting 18- month remission outcomes. Our meta-analysis conducted in 2000 RA participants from 10 studies showed that patients who tapered MTX to targeted therapy alone could maintain remission with an overall pooled OR of 0.81 (0.68, 0.97) (Figure 1). There was no heterogeneity among the studies in this group (I2=0.0%, p=0.788). Our funnel plot indicated high precision and potentially less publication bias. No significant difference in remission outcomes between early RA [OR 0.63 (0.33, 1.18)] and established RA [OR 0.84 (0.69, 1.03)] was observed.

Table 1.

Included Studies

Author/ YearnEarly RABaseline treatmentMTX Taper StrategyREM measureFollow-upCurtis 2020253noETA+MTXStopSDAI48 wksEmery 2019147yesABA+MTXStopSDAI48 wksCohen 2019533noTOFA+MTXStopDAS28-CRP48 wksEmery 2019411yesETA+MTXTaper 4 wksDAS2852 wksPablos 2019165noTCZ+MTXStopDAS2828 wksPope 201988noCZP+DMARDStopDAS2818 mosKremer 2018296noTCZ+MTXStopDAS2852 wksEdwards 2017272noTCZ+MTXTaper 24 wksDAS2848 wksKeystone 2016205noETA+MTXStopDAS2818 mosKeystone 2018140yesADA+MTXStopDAS28-CRP3 years

ETA etanercept, ABA abatacept, TOFA tofacitinib, TCZ tocilizumab, CZP certolizumab pegol, ADA adalimumab, REM remission, wk week, mo month, DAS28 Disease Activity Score 28, SDAI Simplified disease activity index.

Conclusion

Patients with controlled RA have a high probability of maintaining disease control after tapering their MTX to targeted therapy alone, up to 18 months. This review may inform patients with controlled disease on any of a range of targeted therapies and MTX, but who are struggling with MTX-related adverse effects and wish to taper it. Longer follow-up studies with attention to radiographic, functional and patient reported outcomes are needed. The possibility of disease worsening must be discussed with the patient in advance with careful follow-up and prompt re-treatment of disease worsening.

References

[1]Subesinghe S, Scott IC. Expert Rev Clin Pharmacol 2015;8:751-60.

Disclosure of Interests

Charis Meng: None declared, Diviya Rajesh: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Cytodyn, Walgreens, Omar Bruce: None declared, Bridget Jivanelli: None declared, Vivian Bykerk Consultant of: Amgen, Bristol Myers Squibb, Genzyme, Gilead, Janssen, Pfizer, Sanofi-Aventis, UCB., Grant/research support from: NIH (NIAID/NIAMS) grant 1UH2AR067691-01 GRANT11652401 and The Cedar Hill Foundation; institution received grants from Bristol Myers Squibb and Amgen;

POS0642 THE PROBABILITY OF SUSTAINING RHEUMATOID ARTHRITIS REMISSION IN PATIENTS TAPERING TARGETED THERAPY USED AS MONOTHERAPY: A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Up to 30% of RA patients receive monotherapy with biologic (b)DMARDs or JAK inhibitors (i), often due to intolerance of methotrexate (MTX). Monotherapy with IL-6i and JAK-i has been reported to be effective. The EULAR research agenda includes addressing the question of whether tapering of targeted therapy (bDMARDs and JAK-i) used as monotherapy (targeted monotherapy) is possible1.

Objectives

To assess if it is feasible to taper (stop or reduce) targeted monotherapy with controlled RA using existing clinical trial data.

Methods

A systematic review of the literature (2014-2021), cited in Medline, Embase and the Cochrane Library, was performed. Meta-analyses were conducted using random effects models. Forest and funnel plots were created and heterogeneity calculated.

Results

Our search yielded 5762 citations. After de-duplication, screening of titles/abstracts and review of full text articles, we identified 5 studies comparing tapering of targeted monotherapy (TNF-i, tocilizumab (TCZ), abatacept (ABA) and baricitinib) to continuing therapy or other tapering regimens (Table 1). In our meta-analysis of data from 800 patients we observed a trend for lower odds of remission when tapering of targeted monotherapy vs comparator treatment regimen [pooled OR 0.72 (0.35, 1.48)]. In one study comparing stopping monotherapy to continuing MTX, we saw the lowest OR 0.55 (0.20, 1.48). In studies comparing two tapering regimens the pooled OR was higher 2.17 (1.13, 4.16). There was no heterogeneity in the studies which compared tapering to continuing therapy (I2=0.0%, p=0.437) and moderate heterogeneity in the studies that tapered different treatments in both arms (I2=53.7%, p=0.115). Trials using a gradual tapering strategy had a numerically higher odds of remission [OR 2.15 (0.94, 4.92); 3.61(1.85, 7.04)] compared to a trial implementing abrupt withdrawal [OR 1.19 (0.53, 2.68)]. There was a trend for higher remission outcomes in studies of early RA [pooled OR 1.71 (0.72, 4.05)] compared to established RA [pooled OR 1.12 (0.29, 4.27)] (Figure 1). Funnel plots indicate a paucity of studies, and perhaps publication bias.

Table 1.

Included studies.

Author/yearnEarly RAMean Age RangeBaselineTapering strategyComparison arm interventionRemission OutcomeFollow uptreatmentvan Mulligen 2020189No56-57csDMARD + TNFiTaper csDMARD then TNFiTaper in reverse orderDAS44 < 1.624 mosKaneko102No54-58TCZ+MTXStop TCZContinue MTXDAS28 < 2.6104 wks2018vs TCZBijlsma299Yes54TCZ+MTXGradual taper MTX 1st then TCZGradual taper MTXDAS28 < 2.6+SJC≤4104 wks2016vs TCZvs MTXEmery176Yes45-49ABA+MTXStop ABAStop ABA Taper MTX offDAS28-CRP<2.618 mos2015vs ABAvs MTXTakeuchi69Yes48-53Bari 4mgReduce 2mgContinue 4mgCDAI < 2.848 wks2019

ABA abatacept, Bari baricitinib, CDAI Clinical disease activity index, csDMARDS conventional synthetic DMARDs, DAS28 Disease Activity Score 28, MTX methotrexate, SJC swollen joint count, TCZ tocilizumab, wks weeks, mos months.

Conclusion

There are no trials designed to compare tapering targeted monotherapy to continuing it, indicating a significant gap in knowledge in an area of increasing clinical relevance for our patients. There was insufficient evidence to demonstrate the significant effects of tapering targeted monotherapy in RA. Only one study out of 5 compared stopping targeted monotherapy to continuing therapy (MTX), and reported a low OR of remission. Three studies tapered therapy in both arms and one study performed a dose reduction. Our review suggests that stopping targeted monotherapy is unlikely to maintain disease control. More gradual tapering schemes, dose reduction and early treatment of disease may be associated with more successful tapering. More studies are needed to better inform our patients. Currently, we do not recommend stopping targeted monotherapy in RA.

References

[1]Smolen JS, Landewé RBM, Bijlsma JWJ, et al.Ann Rheum Dis 2020;79:685-99.

Disclosure of Interests

Charis Meng: None declared, Diviya Rajesh: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Cytodyn, Walgreens, Omar Bruce: None declared, Bridget Jivanelli: None declared, Vivian Bykerk Consultant of: Amgen, Bristol Myers Squibb, Genzyme, Gilead, Janssen, Pfizer, Sanofi-Aventis, UCB, Grant/research support from: NIH (NIAID/NIAMS) grant 1UH2AR067691-01 GRANT11652401 and The Cedar Hill Foundation; institution received grants from Bristol Myers Squibb and Amgen

POS0417 LESS ACPA EPITOPE EXPANSION IS FOUND IN ACPA-POSITIVE IMMUNE CHECKPOINT INHIBITOR ARTHRITIS PATIENTS COMPARED TO ACPA-POSITIVE RHEUMATOID ARTHRITIS PATIENTS

Background

Immune checkpoint inhibitors (ICI) have markedly improved the treatment of many advanced cancers; however, they can result in immune-related adverse events (irAE) including ICI arthritis (ICI-A). ICI-A often resembles rheumatoid arthritis (RA) and ~9% of ICI-A patients are anti-citrullinated peptide antibody (ACPA) positive. In RA, ACPA epitope expansion occurs over the years prior to onset of clinical disease. In this study we examined the degree of ACPA epitope expansion in seropositive ICI-A patients in order to determine whether it is similar to early RA, or more suggestive of the pre-clinical phase of disease1.

Objectives

To compare the number of ACPA epitopes targeted in seropositive ICI-A versus RA.

Methods

We used clinical data and serum from 12 ACPA+ ICI-A patients enrolled in a prospective registry and 39 ACPA+ RA patients enrolled in the CATCH-US early RA cohort. ACPA screening was done using a commercial ELISA (positive >20 units/mL). A custom, bead-based antigen array was used to identify antibody reactivities to 16 putative RA associated citrullinated proteins. Synovial fluid (SF) samples from 3 of the ICI-A patients were also tested using the bead-based microarray. Hierarchical clustering software was used to create heatmaps to identify ACPA levels. Z-scores for fluorescence intensity were also calculated separately for each peptide, and a fluorescence level above the mean (Z-score>0) was defined as a positive ACPA. The number of positive epitopes for each patient was determined and compared categorically between the ICI-A and RA patients using Fischer’s exact test.

Results

Characteristics of ICI-A and early RA patients are listed in Table 1. Compared to RA patients, ICI-A patients were older (mean 71 years vs. 48 years), more likely to have ever smoked (67% vs. 36%) and less likely to have positive rheumatoid factor (RF) (8% vs. 69%). Median symptom duration for ICI-A patients was 3.7 months compared to 6.7 months in RA patients. The median ACPA titer was lower in ICI-A patients than RA patients (42 units/mL vs. 250 units/mL). As demonstrated in Figure 1, lower signal intensities (level of ACPA) and a lower number of distinct ACPA epitopes were seen in the serum of ICI-A patients compared to RA patients. Of ICI-A patients, 67% were positive for 0-4 ACPA epitopes, 8% for 5-10 epitopes and 25% for >10 epitopes, as opposed to 23% of RA patients positive for 0-4 epitopes, 36% for 5-10 epitopes, and 41% for >10 epitopes (p=0.02). The one ICI-A patient who was also RF positive had 12 positive ACPA epitopes. There was no significant difference in the number of ACPA epitopes in ICI-A patients who were smokers vs. nonsmokers, RA-like vs. PMR-like, or who received ICI combination vs. ICI monotherapy. In the 3 ICI-A patients with synovial fluid samples, SF ACPA was not demonstrated.

Table 1.

Baseline Characteristics of ACPA+ ICI-A and RA Patients

ICI-A (N=12)Early RA (N=39)Age in years, mean (SD)71.0 (8.3)48.2 (14.6)Female Sex7 (58%)33 (85%)White/Caucasian9 (75%)27 (69%)Symptom Duration in months, median [IQR]3.7 [1.0,11.3]6.7 [4.0,9.7]RF Positive1 (8%)27 (69%)ACPA level (units/mL), median [IQR]42.2 [29.4,70.5]250 [107.5,251.0]Obese (BMI≥30)3 (25%)9 (23%)Current/Past Smoker8 (67%)14 (36%)Cancer Typeǂ Melanoma4 (33%) Renal Cell Carcinoma3 (25%)ICI Regimen PD-1/PD-L17 (58%) CTLA-4+PD-15 (42%)ICI-A Phenotype RA-like9 (75%) PMR-like3 (25%)

ǂOther cancer types in ICI-A patients included urothelial carcinoma (n=2), non-small cell lung cancer (n=2), and head and neck cancer (n=1).

Figure 1.

Heat Map of ACPA repertoire in RA Patients and ICI-A Patients.

Conclusion

ICI-A patients had lower ACPA titers and targeted fewer ACPA epitopes than early RA patients. It remains to be determined if ICI-A represents an accelerated model of RA pathogenesis with ICI triggering an early transition from pre-clinical to clinical disease. This would require sequential sampling and analysis.

References

[1]Sokolove J. et al. PLoS One. 2012;7(5)e35296

Disclosure of Interests

Diviya Rajesh: None declared, Nilasha Ghosh: None declared, Jessica Kirschmann: None declared, Karmela Kim Chan: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Walgreens, and Cytodyn, Susan Goodman Consultant of: UCB Data Monitoring and Safety Board, Grant/research support from: Novartis, Vivian Bykerk Consultant of: Amgen, Bristol Myers Squibb, Genzyme, Gilead, Janssen, Pfizer, Sanofi-Aventis, and UCB, Grant/research support from: Bristol Myers Squibb, Amgen, and The Cedar Hill Foundation, William Robinson: None declared, Anne Bass: None declared.

Comparison of the efficacy of liraglutide with pioglitazone on dexamethasone induced hepatic steatosis, dyslipidemia and hyperglycaemia in albino rats

Objectives:

To evaluate the efficacy of liraglutide with pioglitazone for prevention of dexamethasone induced hepatic steatosis, dyslipidemia and hyperglycemia in Albino rats.

Materials and Methods:

There were four groups of six rats each. First group received dexamethasone alone in a dose of 8 mg/kg intraperitoneally for 6 days to induce metabolic changes and considered as dexamethasone control. Second group received liraglutide 1.8 mg/kg subcutaneously 6 days before dexamethasone and 6 days during dexamethasone administration. Third group received pioglitazone 45 mg/kg orally 6 days before dexamethasone and 6 days during dexamethasone administration. Fourth group did not receive any medication and was considered as normal control. Fasting blood sugar, lipid profile, blood sugar 2 h after glucose load were measured. Liver weight, liver volume, and histopathological analysis were done.

Results:

Dexamethasone caused hepatomegaly, dyslipidemia, and hyperglycemia. Both pioglitazone and liraglutide significantly reduced hepatomegaly, dyslipidemia and hyperglycemia (P < 0.01). Reduction of blood sugar levels after glucose load was significant with pioglitazone when compared with liraglutide (P < 0.01).

Conclusion:

Liraglutide has comparable efficacy to pioglitazone in prevention of dexamethasone induced hepatomegaly, dyslipidemia and fasting hyperglycemia.

Investigations on luminescence performance of Sm3+ ions activated in multi-component fluoro-phosphate glasses

Different metal oxide based fluoro-phosphate glasses doped with Sm(3+) ions are investigated using XRD, SEM with EDS, FTIR, Raman spectra, optical absorption and photo-luminescence techniques. These glass matrices have been prepared by conventional melt quenching technique. The glassy nature of the present glass matrices are confirmed by XRD profiles and SEM photographs. The composition of the glasses is checked by EDS. Based on FTIR and Raman spectra, the authors have analyzed functional groups that are present in the glass matrices. Judd-Ofelt intensity parameters, Ωλ (λ=2,4,6) have been evaluated from absorption spectra. Radiative parameters such as radiative transition probabilities (AR), radiative lifetimes (τR), integrated absorption cross sections (Σ) and branching ratios (βR) are calculated using Judd-Ofelt intensity parameters. From the photoluminescence spectra, experimental branching ratios (βexp) and stimulated emission cross-sections (σP) for all the observed emission transitions are calculated. To investigate luminescence potentiality of (4)G5/2→(6)H7/2 emission level of Sm(3+) doped different fluorophosphate glasses, experimental radiative lifetimes (τexp) are obtained from decay curve analysis for all glass matrices. Finally, these observed results are discussed and compared with the literature data.

Spectroscopic investigations on Pr³+ and Nd³+ doped strontium-lithium-bismuth borate glasses

Spectroscopic investigations on different concentrations (0.1, 0.5, 1.0, 1.5 and 2.0mol%) of Pr(3+) and Nd(3+) doped strontium lithium bismuth borate glasses have been done. X-ray diffraction, SEM with EDS, absorption and luminescence spectra were recorded for all the glass matrices and analyzed. X-ray diffraction profiles and SEM images conformed amorphous nature of investigated glass samples. EDS spectra of host glass and Pr(3+)doped glass matrices gave information about the chemical composition of glass samples. From the absorption spectra of Pr(3+) and Nd(3+) ions, Judd-Ofelt (J-O) intensity parameters (Ω(λ),λ=2, 4 and 6) have been calculated and compared with other glass matrices. The emission characteristics such as radiative lifetimes (τ(R)), measured and calculated branching ratios (β) and stimulated emission cross-sections (σ(P)) have been obtained for the observed emission transitions of Pr(3+) and Nd(3+) ions in the above glass matrix for all the concentrations. From the emission spectra of Pr(3+) and Nd(3+) doped glass matrices, the effect of concentration on the quenching of intensity of (1)D(2)→(3)H(4) transition of Pr(3+) ion and (4)F(3/2)→(4)I(9/2), (4)I(11/2) and (4)I(13/2) transitions of Nd(3+) have been studied and discussed.

Introducing operations research into management and policy practices of a non-governmental organization (NGO): a partnership between an Indian leprosy NGO and an international academic institution

This paper reports on a partnership between LEPRA, a non-governmental organization (NGO), and the London School of Hygiene and Tropical Medicine (LSHTM) to explore the feasibility and appropriateness of incorporating operations research into the management and decision-making of a leprosy NGO. A pilot study in Orissa was used to determine the advantages and disadvantages of introducing operations research to assist in decision-making and programme implementation within the organization. The results highlight the difficulty and complexity of the process, but point to several important themes: partnership, changing perspectives, use of time and priority-setting, identification of gaps in systems, and building institutional and personal capabilities. The results of the study provide support to encourage NGOs to become actively involved in research. Because of their work and service to local communities, NGOs have the opportunity to collect information about the perceptions, resources and constraints of individuals, families and the communities themselves in accessing appropriate care. Their proximity to communities gives them a feeling of responsibility for ensuring that this information is translated to the district, national and ultimately international level. This will help to ensure the creation of appropriate infectious disease control policies that support the needs of patients. 'Outside' academic institutions can help NGOs to facilitate this up-stream flow of information from the local to the national and international level, to help to ensure that international disease control policies are appropriately serving local communities.

Lessons in integration--operations research in an Indian leprosy NGO

Since the Alma Ata Declaration in 1978, health systems supporting the treatment and control of infectious diseases like leprosy and tuberculosis have been encouraged to 'integrate' into the primary health care structure within countries. Now, more than 20 years later, countries are still grappling with the concept of integration and looking for ways to achieve it. This study reports findings from a leprosy/Tuberculosis/AIDS awareness pilot project conducted by LEPRA India, a leprosy non-governmental organization (NGO), between 1996 and 2000 in Koraput district, Orissa. The project addressed the issue of integration on two levels. On the one hand LEPRA used the context of the project to explore ways in which to integrate TB services into their existing leprosy control structure. On the other hand, lessons from the pilot study were intended to help the organization find ways of linking with the government health care structure. Following a 'qualitative approach', this operations research project assessed the perceptions of communities and providers about leprosy and tuberculosis services. Providers across the spectrum of this plural healthcare system were asked to provide comment on developing stronger networks with each other, with NGOs and with government, while patients and communities were asked to describe the resources available to them and the constraints they face in accessing health care in general, and for leprosy and TB in particular. LEPRA staff from top management to the outreach workers were also approached for their views. Patients and communities noted that physical access to treatment was a major constraint, while the existence of local providers and family support structures facilitated health and health care. Providers expressed a willingness to collaborate (with LEPRA and the government), but lacked training, adequate staff support and the appropriate equipment/technical resources. Also lacking were adequate information campaigns to inform the public about these diseases and their treatment. This information has provided LEPRA with an understanding of how they might best fill gaps in the existing system and therefore assist in the process of integrating services in their own organization and through the primary health care structure. To achieve this aim, LEPRA will increasingly become involved in developing relationships and partnerships with government in the delivery of training and services and in infrastructure development.

Ras mutation, irrespective of cell type and p53 status, determines a cell's destiny to undergo apoptosis by okadaic acid, an inhibitor of protein phosphatase 1 and 2A

Okadaic acid (OA), a toxin from the black sponge Halicondria okadai, is a specific inhibitor of serine/threonine protein phosphatases 1 (PP1) and 2A (PP2A). OA is a tumor promoter but also induces apoptosis in some tumor cell lines. In this study, we determined whether ras mutation and/or p53 status are characteristics associated with the cell's sensitivity to the induction of apoptosis by OA. Several cell lines that differed in ras and p53 mutations were treated with OA (10-100 nM). At 24 to 48 h after treatment, the percentage of cells undergoing apoptosis was quantitated. The cell lines with mutations in either H-ras (human bladder carcinoma cell line T24 and mouse keratinocyte cell line 308), or K-ras (human colon carcinoma cell lines DLD-1 and HCT116; human prostate cancer cell lines LNCaP and PC-3; human lung cancer cell lines Calu-6 and SKLU-1; and human pancreatic cancer cell line MIAPaCa2) were more sensitive to OA-induced apoptosis (3- to 10-fold) than the cell lines that lacked the ras mutation (mouse epidermal cell lines C50 and JB6; murine fibroblast cell line NIH3T3; human colon cancer cell line HT29; human kidney epithelial cell line Hs715.K; and human pancreatic cancer cell line Bx-PC3). Similarly, using isogenic cell lines we found that overexpression of mutated H-ras in NIH3T3 and in SV40 immortalized human uroepithelial cells (SVHUC) enhanced their sensitivity to undergo apoptosis in response to OA treatment. The T24, DLD-1, SKLU-1, Calu-6, and MIAPaCa2 cell lines express mutated p53. The SVHUC as well as their ras-transfected counterparts have inactive p53 due to complex formation between large "T" antigen and p53. Taken together, these results imply that OA-induced apoptosis may involve a p53-independent pathway. The transfectants (NIH3T3-ras and SVHUC-ras), which express mutated H-ras, have up-regulated PP2A activity. OA treatment inhibited in vivo the levels of PP1 and PP2A activity, and induced apoptosis in SVHUC-ras and other cell lines. We conclude that OA-induced cell death pathway in ras-activated cell lines may involve a cross talk between PP1 and PP2A and ras signaling pathways. In light of the present results, the current theory that OA promotes mouse skin tumor formation by selective expansion of initiated cells that harbor ras mutations needs reevaluation.