Hypoxia-Induced Radioresistance in Human Non-Small Cell Lung Carcinoma Cell Lines

Lung cancer accounts for 25 % of cancer-related deaths. Non-small cell lung carcinoma (NSCLC) constitutes 85 % of all lung cancers. Radiotherapy is used in treatment of over half of lung cancer patients. Tumor hypoxia is associated with treatment resistance particularly in the context of radiotherapy. Targeting tumor hypoxia to increase radiotherapy efficacy has met limited success clinically with no measurable mortality benefit. High linear energy transfer (LET) carbon ions are being used increasingly in cancer clinical trials and have the theoretical advantage of being less sensitive to the influence of oxygen. Studying DNA damage response (DDR) to low- (X-rays) and high-LET ionizing radiation under hypoxia may help identify molecular processes that can be potentially targeted therapeutically to overcome hypoxia-induced radioresistance. Additionally, tumor cells often experience reversible hypoxia due to tumor shrinkage secondary to treatment, neo-angiogenesis as well as intermittent vasospasm of feeding vessels. Thus, impact of reoxygenation on radioresistance also warrants greater understanding. The Nuclear Factor Kappa B (NF-kB) pathway is associated with cellular inflammatory response to stressors like ionizing radiation and hypoxia and has been associated with enhanced cell survival. However, the role of NF-kB pathway in hypoxia-induced radioresistance remains elusive. Therefore, the radioresistance of NSCLC cells was evaluated under continuous hypoxia and following reoxygenation by performing clonogenic assays following irradiation with the objective of correlating hypoxia induced radioresistance in NSCLC cells to DDR in terms of DNA double strand break (DSB) induction, DSB repair, cell cycle progression as well as activation of pro-survival NF-kB pathway. A549 (p53-wt) and H358 (p53-null) NSCLC cell lines were incubated after seeding for 48 h under hypoxia (0.1 % and 1 % O2) and normoxia (20 % O2) and irradiated using X-rays (200 KeV) and carbon ions (on target energy 25.7 MeV/nucleon). Following irradiation, hypoxic cells were either allowed to reoxygenate (transient hypoxia) or kept hypoxic (continuous hypoxia) till end of experiments. Radioresistance was evaluated in normoxic, continuously hypoxic and transiently hypoxic cells using Puck’s colony forming ability (CFA) assay. DDR four hours following irradiation was assessed at transcriptional level in terms of cell cycle modulation, DNA DSB repair and activation of pro-survival NF-kB pathway by carrying out RNA sequencing and differential expression analysis of relevant genes in continuously and transiently hypoxic cells in comparison to normoxic controls. Cell cycle progression was determined by flow cytometry of cells after staining their nuclei with 4’,6’-diamidino-2-phenylindole (DAPI). DSB induction and repair was assessed using gamma H2AX immunofluorescence microscopy and NF-kB pathway activation was evaluated by p65 (NF-kB subunit) nuclear translocation using p65 immunofluorescence microscopy, and by measuring production of NF-kB target proteins, interleukin (IL) 6 and IL-8. CFA assays revealed that hypoxic cells were more radioresistant compared to normoxic controls when they were given 24 h to repair (late plating) following both X-rays and carbon ions exposure. Radioresistance was higher at 0.1 % O2 compared 1 % O2. Continuously hypoxic cells were more radiosensitive compared to normoxic controls when they were immediately re-seeded for growth of colonies following irradiation (immediate plating). This radiosensitivity was reversed if hypoxic cells were reoxygenated following irradiation (transient hypoxia). Carbon ions had a greater relative biological effectiveness (RBE) in killing hypoxic cells compared to X-rays. Cell cycle progression under hypoxia following both X-rays and carbon ions exposure in A549 and H358 cell lines was slowed as indicated by a greater proportion of cells in G1 phase and smaller population of cells in G2 phase compared to normoxic controls. Phase redistribution was similar at 0.1 % and 1 % O2. Differential expression analysis of cell cycle genes revealed weak transcriptional regulation in both cell lines indicating importance of post-translational cell cycle regulation in response to irradiation under hypoxia. Reoxygenation did not affect cell cycle phase distribution in first 24 h. DSB induction assessment based on H2AX foci count 1 h after irradiation was lower under continuous and transient hypoxia in case of X-rays exposure but not in case of carbon ions exposure. No residual DSBs were observed at a dose of 2 Gy X-rays but DSBs induced by carbon ions took longer to resolve compared to those caused by X-rays. Differential expression analysis of DSB repair genes was unremarkable but that for NF-B target genes showed overexpression of several pro-survival and pro-proliferation genes under hypoxia. The gene expression signature of both cell lines was unique with minimal overlap. Gene expression signature also varied following X-rays and carbon ions exposure. In case of H358 cells, reoxygenation resulted in transcriptional regulation of several genes not regulated under continuous hypoxia. IL-6 (following carbon ions exposure) and IL-8 (following both X-rays and carbon ions exposure) were upregulated in A549 cells while in H358 cells, only IL-8 was upregulated upon reoxygenation. Nuclear translocation of cytosolic p65 was found to occur earlier (at 2 h vs. 6 h) in A549 and H358 cells under continuous hypoxia (1 % O2) following both X-rays and carbon ion exposure compared to normoxia. Reoxygenation had a minimal effect on p65 nuclear translocation in A549 cells. In H358 cells, p65 nuclear localization increased in response to reoxygenation but was not affected by irradiation. Both IL-6 and IL-8 secretion by A549 cells was amplified under hypoxia regardless of reoxygenation and irradiation resulted in its further increase. IL-8 secretion by H358 cells was increased under both continuous and transient hypoxia but irradiation further increased its production only under continuous hypoxia. Hypoxia-induced radioresistance in continuously and transiently hypoxic A549 cells following X-rays and carbon ion exposure was found to be associated with cell cycle phase redistribution toward the radioresistant G1 phase, lesser DSB induction, earlier NF-B activation, greater NF-kB target gene expression and higher NF-B target protein synthesis and secretion. The same was true in case of continuously hypoxic H358 cells following X-rays exposure. However, transiently hypoxic H358 cells behaved differently: reoxygenation increased basal p65 nuclear translocation and IL-8 secretion but irradiation did not lead to further increase in p65 nuclear intensity and IL-8 secretion. Hypoxia-induced radioresistance effects faster growing cells (A549) more than less rapidly dividing cells (H358). Reoxygenation does not alter effects of hypoxia on cell survival, DNA damage and cell cycle but it does affect both cell lines differently in terms of NF-kB pathway activation and transcription of its target genes. While this work does not establish a causal relationship between NF-kB activation and radioresistance seen in hypoxic NSCLC cells, the association does show promise for further investigation into NF-kB as a potential molecular target for therapy in NSCLC. Although NF-kB activation is seen following high LET radiation exposure as well, hypoxic cells are more radiosensitive to carbon ions compared to low LET X-rays. Moreover, IL-6 and IL-8 secretion may serve as potential prognostic indicators of radioresistance

Womens\u27 perceptions regarding obstetric complications and care in a poor fishing community in Karachi

Objective: To assess the knowledge of women about obstetric complications and care.Methods: The study was conducted in a remote coastal community in Karachi in 1999, where the Department of Community Health Sciences of Aga Khan University is operating its primary health care project since 1996. The information was collected using a structured questionnaire, interviewing a representative sample of 329 married-women of reproductive age, selected systematically from the community.Results: The mean age of the respondents was 29 years. On average they were married for 11 years and had four living children. Almost half of them had no antenatal care in their last pregnancy and 75% delivered at home. The findings indicate a poor knowledge of common and serious pregnancy related complications based on their perception related to danger signs. Five percent of the women perceived absent/decreased fetal movement as a danger sign of pregnancy. Other reported danger signs included premature uterine contraction by 3%, premature rupture of membranes by 3%, convulsions by 13%, obstructed labor by 23% and bleeding by 39%. Moreover, the women\u27s perception regarding obstetric care suggests that unsafe practices prevail: 86% of women thought that a case of ante-partum hemorrhage should be examined internally and 50% thought that no precaution is required to sterilize the instrument for cutting the cord.CONCLUSION: There is a clear need to create awareness regarding obstetric complications through a targeted community based health educational intervention aiming to promote early recognition of the obstetric emergency at the household level and also to create a demand of safe obstetric practices

Impact of sudarshan kriya yoga on mean arterial blood pressure and biochemical parameters in medical students

Background: Yogic life style and various yogic practices help man to strengthen his body and mind. Yogic breathing is defined as a manipulation of breath movement. The practice of yoga has beneficial effect on biochemical and physiological functions.Methods: This study was planned to see the effect of sudarshan kriya yoga on blood pressure and biochemical parameters in medical students at medical college. The study conducted on 30 medical students of age 18-21 years, at LLRM Medical College, Meerut, U.P (India) over a period of three months.Results: The result showed that yoga had beneficial effect on blood pressure, blood glucose level and cholesterol level. The mean blood pressure shows highly significant reduction after 3 months of yoga practice. It was also found that there is significant improvement in Lipid Profile parameters after sudarshan kriya yoga practices.Conclusions: Living a happy and healthy life on all planes is possible through the unified practice of sudarshan kriya yoga (SKY) along with asana and pranayam. The practice of SKY seems to be beneficial on mean blood pressure and biochemical parameters in normal healthy individuals. This unique breathing practice is a potent energizer

Vitamin D accelerates clinical recovery from tuberculosis: results of the SUCCINCT Study [Supplementary Cholecalciferol in recovery from tuberculosis]. A randomized, placebo-controlled, clinical trial of vitamin D supplementation in patients with pulmonary tuberculosis\u27.

BACKGROUND: Vitamin D enhances host protective immune responses to Mycobacterium tuberculosis by suppressing Interferon-gamma (IFN-g) and reducing disease associated inflammation in the host. The objectives of this study were to determine whether vitamin Dsupplementation to patients with tuberculosis (TB) could influence recovery. METHODS: Two hundred and fifty nine patients with pulmonary TB were randomized to receive either 600,000 IU of Intramuscular vitamin D3 or placebo for 2 doses. Assessments were performed at 4, 8 and 12 weeks. Early secreted and T cell activated 6 kDa (ESAT6) and Mycobacterium tuberculosis sonicate (MTBs) antigen induced whole blood stimulated IFN-g responses were measured at 0 and 12 weeks. Statistical comparisons between outcome variables at 0 and 12 weeks were performed using Student\u27s t-test and Chi2 tests. RESULTS: After 12 weeks, the vitamin D supplemented arm demonstrated significantly greater mean weight gain (kg)+3.75, (3.16-4.34) versus+2.61 (95% CI 1.99-3.23) p 0.009 and lesser residual disease by chest radiograph; number of zones involved 1.35 v/s 1.82 p 0.004 (95% CI 0.15, 0.79) and 50% or greater reduction in cavity size 106 (89.8%) v/s 111 (94.8%), p 0.035. Vitamin D supplementation led to significant increase in MTBs-induced IFN-g secretion in patients with baseline \u27Deficient\u27 25-hydroxyvitamin D serum levels (p 0.021). CONCLUSIONS: Supplementation with high doses of vitamin D accelerated clinical, radiographic improvement in all TB patients and increased host immune activation in patients with baseline \u27Deficient\u27 serum vitamin D levels. These results suggest a therapeutic role for vitamin D in the treatment of TB

Requirements for large-scale adoption of rapid manufacturing technologies

Despite the use of Additive Manufacturing (AM) technologies in a lot of applications including the production of some high-value products for end use, it is still very much an untapped potential. There is an increase in usage of AM technology for the manufacture of end-use products (Rapid Manufacturing (RM)) in recent years, but mass use of the technology in terms of speed, cost and quality, which is acceptable by the general consumer, is still not widely in existence today. The concept of RM as a viable production process is still not understood by many businesses/consumers, with thinking still dominated by the AM technologies for Rapid Prototyping (RP) applications. A key difference between RM and RP is in the supply chain. The RM supply chain is much more complicated than the RP supply chain. This research conducted a Delphi Study to identify the requirements or prerequisites necessary for the use of RM technologies as a viable means to manufacture end used products (RM application of AM) in mass scale. The paper identifies 36 requirements or pre-requisites and classified them into various classes of importance in order to highlight their significance. In addition to supply chain issues, the requirements unearthed are factors or features about RM technology (equipment), materials and processes that need modification, upgrading or creation

Uloga prijeoperacijskog karcinoembrijskog antigena u recidiviranju resektabilnog kolorektalnog karcinoma

In colorectal carcinoma, carcinoembryonic antigen (CEA) is a recommended marker for surveillance after curative resection. The aim of the present study was to determine the association of preoperative CEA with recurrence of colorectal carcinoma in our population. The study included 55 patients with all operable stages of colorectal adenocarcinoma treated during the 2012-2014 period, evaluated retrospectively and followed-up for recurrence for 2 years. Data on the baseline (preoperative) CEA levels were retrieved from patient files. On data analysis, SPSS 16.0 was used. In patients with normal preoperative CEA, the rate of recurrence was significantly low (p=0.008) and the likelihood of no recurrence 1.55-fold greater as compared to patients with raised initial CEA levels (p=0.028). In patients with raised preoperative CEA, the risk of recurrence was 5.26-fold greater as compared to those with normal CEA levels (p=0.028). A significant weak positive correlation (rs=0.297) was found between raised CEA and recurrence. A highly significant (p=0.002) moderate positive correlation was recorded in patients aged <50 and moderate positive correlation of borderline significance in males (rs=0.324, p=0.058). Sensitivity was 94.4% and specificity 32.4% in predicting recurrence. Accordingly, preoperative elevated CEA showed a significant weak positive correlation with recurrence while normal preoperative CEA moderately decreased the likelihood of recurrence.U kolorektalnom karcinomu preporuča se karcinoembrijski antigen (CEA) kao biljeg u praćenju bolesnika nakon resekcije karcinoma. Cilj ovoga istraživanja bio je utvrditi udruženost prijeoperacijske razine CEA s recidiviranjem kolorektalnog karcinoma u našoj populaciji. U istraživanje je bilo uključeno 55 bolesnika sa svim operabilnim stadijima kolorektalnog adenokarcinoma liječenih u razdoblju od 2012. do 2014. godine. Bolesnici su retrospektivno procijenjeni i praćeni zbog recidiva tijekom dvije godine. Podaci o bazalnim (prijeoperacijskim) razinama CEA preuzeti su iz medicinske dokumentacije bolesnika. Analiza podataka provedena je pomoću SPSS 16.0. Kod bolesnika s normalnom prijeoperacijskom razinom CEA stopa recidiva bila je značajno niža (p=0,008), a vjerojatnost izostanka recidiva 1,55 puta veća u usporedbi s bolesnicima s povišenim početnim razinama CEA (p=0,028). Kod bolesnika s povišenim prijeoperacijskim razinama CEA rizik od recidiva bio je 5,26 puta veći u usporedbi s onim u bolesnika s normalnim razinama CEA (p=0,028). Značajna slabo pozitivna korelacija (rs=0,297) utvrđena je između povišene razine CEA i recidiva. Visoko značajna (p=0,002) umjereno pozitivna korelacija zabilježena je u bolesnika mlađih od 50 godina te umjereno pozitivna korelacija granične značajnosti kod muškaraca (rs=0,324, p=0,058). Utvrđena je osjetljivost od 94,4% i specifičnost od 32,4% u predviđanju recidiva. Dakle, povišena prijeopearcijska razina CEA pokazala je značajnu slabo pozitivnu korelaciju s recidivima, dok je normalna prijeoperacijska razina CEA umjereno snizila vjerojatnost recidiva

Analytical Model for Underwater Wireless Sensor Network Energy Consumption Reduction

In an Underwater Wireless Sensor Network (UWSN), extreme energy loss is carried out by the early expiration of sensor nodes and causes a reduction in efficiency in the submerged acoustic sensor system. Systems based on clustering strategies, instead of each node sending information by itself, utilize cluster heads to collect information inside the clusters for forwarding collective information to sink. This can effectively minimize the total energy loss during transmission. The environment of UWSN is 3D architecture-based and follows a complex hierarchical clustering strategy involving its most effecting unique parameters such as propagation delay and limited transmission bandwidth. Round base clustering strategy works in rounds, where each round comprises three fundamental stages: cluster head selection, grouping or node association, and data aggregation followed by forwarding data to the sink. In UWSN, the energy consumed during the formation of clusters has been considered casually or completely evaded in the previous works. In this paper, the cluster head setup period has been considered the main contributor to extra energy utilizer. A numerical channel model is proposed to compute extra energy. It is performed by using a UWSN broad model. The results have shown that extra maximum energy consumption is approximately 12.9 percent of the system total energy consumed in information transmissions

Low-Carbon Energy Technologies: Potentials of Solar and Nuclear Energy Sources for Sustainable Economic Development in Bangladesh

Electricity shortage has become a major challenge to continued economic growth in Bangladesh. The country is growing in terms of GDP growth at a rate of 7% a year. Bangladesh is expected to move towards 23rd position globally by 2050 from its position 31 in 2014, in terms of GDP at purchasing power parity (PPP). The demand for electricity is forecasted to be 61,164 MW within the same period. Currently, electricity generation in Bangladesh is highly dependent on fossil fuels, nearly 59% is produced from natural gas followed by furnace oil, diesel and coal, while only 3% from renewables. Electricity generation is the largest single source of GHG (greenhouse gas) emissions in Bangladesh, and thus finding alternative energy source has become imperative for the country. Solar and nuclear energy sources have the potentials to be utilized for low-carbon energy sector and thus for a sustainable economic development in Bangladesh. Barriers to solar and nuclear energy will be reduced significantly in coming years with technological advancement. However, energy policies need to be revised to facilitate low-carbon energy technologies. Besides, more international collaboration is highly required not only to import new technologies but also to enhance the capacity of research and development (R&amp;D) as well as overall adoption of the technologies

Adaptive energy efficient circular spinning protocol for dynamic cluster based UWSNs

Under Water Sensor Network (UWSN) is a novel paradigm for exploring marine environments such as offshore and mineral exploration, underwater surveillance, and sea habitat monitoring. However, a good quality underwater communication is difficult to achieve due to different constraints such as limited bandwidth, acoustic propagation issues, delays, battery replacement hitches, etc. In recent works, efficient energy-based designing and overall performance evaluation of the UWSN has become a major consideration. Cluster-based sensor networks have proven to be a successful way to increase the network's load congruency and scalability while lowering the system's total energy consumption. Usually, clustering algorithms work in three phases; cluster setup, data collection, and transmission to sink. In these types of dynamic cluster-based networks, energy consumed in cluster setup has been considered insignificant. Since these network energy consumptions are not part of data communication, we consider it extra energy consumption. In this paper, a new Energy Efficient Circular Spinning (EECS) dynamic clustering algorithm has been proposed to provide an improved cluster setup system and to minimize energy usage in re-clustering or cluster setup. Our proposed EECS mechanism suggests that system performance can improve by reducing the Cluster Head (CH) selection phase or cluster setup phase and can ultimately minimize the energy consumption of networks. It is demonstrated that by reducing the transmission of superfluous control messages during the cluster arrangement stage, approximately 21.5% to28.4% of the total network energy expended can be saved. This paper also compares the extra energy consumption, total network energy consumption, and life of the network in our proposed EECS mechanism to two different mechanisms, (1) Adaptive LEACH for UW, (2) UMOD-LEACH. The optimum value of cluster head has been calculated from energy consumption of different protocols and results show that our proposed EECS can prolong network lifetime by 21.5% and 28.4%from the above-mentioned algorithms consequently. In future, we will extend outwork for multi-hop dynamic cluster base mechanism for UW