46 research outputs found
Identifying needs and barriers to diabetes education in patients with diabetes
Objective: To assess the needs, awareness and barriers to diabetes education for self management and to facilitate the initiation of an education programme promoting self care among diabetics and their families.Methods: A qualitative study was conducted among adult diabetics attending outpatient clinics in a tertiary care teaching hospital in Karachi, Pakistan. Semi-structured interviews were conducted on 27 subjects (11 men; 16 women) to identify dominant themes and priority issues.Results: Participants displayed great deal of variation with respect to level of knowledge and motivation for education. Most believed that diabetes was caused by stress. Family was perceived to be a source of positive support. Relative ease of adherence to pharmacological regimens as compared to diet and exercise was reported. Participants expressed frustration at chronicity of disease and fear of developing certain specific complications and inheritance by their children. Barriers to enhancing knowledge included \u27No need for further information\u27, distance from training institutions and other priorities.CONCLUSION: Knowledge, beliefs and fears about diabetes, family influence and accessibility of healthcare, affects management behaviours and learning. Understanding needs and expectations of people with diabetes is essential in initiating and improving the outcomes of education programme for diabetes self care
Propene Production by Butene Cracking. Descriptors for Zeolite Catalysts
This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Catalysis, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acscatal.0c02799[EN] Among the possible on-purpose technologies for propene production, direct conversion of butene-rich fractions to propene represents an attractive alternative to conventional routes such as steam cracking or fluid catalytic cracking. Here, we present an approach for designing an efficient ZSM-5-based catalyst for the selective cracking of butenes to propene by properly balancing diffusional and compositional effects. Instead of the large coffin-shaped ZSM-5 crystallites with very high Si/Al ratios generally reported, the optimal catalyst in terms of propene selectivity and catalyst life was found to be a ZSM-5 zeolite with a squared morphology, submicron-sized crystals (0.8 x 0.3 x 1.0 mu m), and a Si/Al molar ratio of around 300. For this crystal conformation, the short dimensions of both sinusoidal and straight channels facilitate propene diffusion and reduce its consumption in consecutive reactions, limiting the formation of C5+ oligomers and aromatics and maximizing propene selectivity. Coffin-type ZSM-5 crystals, with higher diffusional restrictions than square-shaped crystals, show faster catalyst deactivation than the latter, independently of the crystal size and Al content. However, among the ZSM-5 zeolite crystallites with a coffin morphology, the one presenting intergrowths on the (010) face, with a larger proportion of sinusoidal channels, shows a lower aromatic selectivity and deactivation rate, whereas the other two, with straight channels open to the clean (010) faces, favor the formation of aromatics by direct cyclization-dehydrogenation of oligomeric intermediates.This work has been supported by Saudi Aramco, by the Spanish Government-MICINN through "Severo Ochoa" (SEV-2016-0683) and RTI2018-101033-B-I00, and by Generalitat Valenciana (AICO/2019/060). We thank the Electron Microscopy Service of the UPV for their help in sample characterization.Del Campo Huertas, P.; Navarro Villalba, MT.; Shaikh, SK.; Khokhar, MD.; Aljumah, F.; Martínez, C.; Corma Canós, A. (2020). Propene Production by Butene Cracking. Descriptors for Zeolite Catalysts. ACS Catalysis. 10(20):11878-11891. https://doi.org/10.1021/acscatal.0c02799S11878118911020Agency, I. E. 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Analysis of the ITQ-12 Zeolite Performance in Propane−Propylene Separations Using a Combination of Experiments and Molecular Simulations. The Journal of Physical Chemistry C, 114(35), 14907-14914. doi:10.1021/jp101744kPalomino, M., Cantín, A., Corma, A., Leiva, S., Rey, F., & Valencia, S. (2007). Pure silica ITQ-32 zeolite allows separation of linear olefins from paraffins. Chem. Commun., (12), 1233-1235. doi:10.1039/b700358gBlay, V., Miguel, P. J., & Corma, A. (2017). Theta-1 zeolite catalyst for increasing the yield of propene when cracking olefins and its potential integration with an olefin metathesis unit. Catalysis Science & Technology, 7(24), 5847-5859. doi:10.1039/c7cy01502jCorma, A., Corresa, E., Mathieu, Y., Sauvanaud, L., Al-Bogami, S., Al-Ghrami, M. S., & Bourane, A. (2017). Crude oil to chemicals: light olefins from crude oil. Catalysis Science & Technology, 7(1), 12-46. doi:10.1039/c6cy01886fChen, J. Q., Bozzano, A., Glover, B., Fuglerud, T., & Kvisle, S. (2005). Recent advancements in ethylene and propylene production using the UOP/Hydro MTO process. Catalysis Today, 106(1-4), 103-107. doi:10.1016/j.cattod.2005.07.178Al-Khattaf, S. S.; Palani, A.; Bhuiyan, T. I.; Shaikh, S.; Akhtar, M. N.; Aitani, A. M.; Al-Yami, M. A. Dual Catalyst System for Propene Production. U.S. Patent 10,052,618 B2, 2018.Alshafei, F. H.; Khokhar, M. D.; Sulais, N. A.; Alalouni, M. R.; Shaikh, S. K. Multiple-Stage Catalyst System for Self-Metathesis with Controlled Isomerization and Cracking. U.S. Patent 2018/0,208,524 A1, 2018.Khokhar, M. D.; Alshafei, F. H.; Sulais, N. A.; Shaikh, S. K.; Abudawoud, R. H. Dual Catalyst Processes and Systems for Propene Production. U.S. Patent 10,329,225 B2, 2019.Shaikh, S.; Jamal, A.; Zhang, Z. Systems and Methods for Producing Propene. U.S. Patent 9,834,497 B2, 2017.Arudra, P., Bhuiyan, T. I., Akhtar, M. N., Aitani, A. M., Al-Khattaf, S. S., & Hattori, H. (2014). Silicalite-1 As Efficient Catalyst for Production of Propene from 1-Butene. ACS Catalysis, 4(11), 4205-4214. doi:10.1021/cs5009255Lin, L., Qiu, C., Zhuo, Z., Zhang, D., Zhao, S., Wu, H., … He, M. (2014). Acid strength controlled reaction pathways for the catalytic cracking of 1-butene to propene over ZSM-5. Journal of Catalysis, 309, 136-145. doi:10.1016/j.jcat.2013.09.011ZHAO, G., TENG, J., XIE, Z., JIN, W., YANG, W., CHEN, Q., & TANG, Y. (2007). Effect of phosphorus on HZSM-5 catalyst for C4-olefin cracking reactions to produce propylene. Journal of Catalysis, 248(1), 29-37. doi:10.1016/j.jcat.2007.02.027Blay, V., Epelde, E., Miravalles, R., & Perea, L. A. (2018). Converting olefins to propene: Ethene to propene and olefin cracking. Catalysis Reviews, 60(2), 278-335. doi:10.1080/01614940.2018.1432017Shi, J., Wang, Y., Yang, W., Tang, Y., & Xie, Z. (2015). Recent advances of pore system construction in zeolite-catalyzed chemical industry processes. 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Applied Catalysis A: General, 290(1-2), 191-199. doi:10.1016/j.apcata.2005.05.028Zhao, G., Teng, J., Zhang, Y., Xie, Z., Yue, Y., Chen, Q., & Tang, Y. (2006). Synthesis of ZSM-48 zeolites and their catalytic performance in C4-olefin cracking reactions. Applied Catalysis A: General, 299, 167-174. doi:10.1016/j.apcata.2005.10.022SAZAMA, P., DEDECEK, J., GABOVA, V., WICHTERLOVA, B., SPOTO, G., & BORDIGA, S. (2008). Effect of aluminium distribution in the framework of ZSM-5 on hydrocarbon transformation. Cracking of 1-butene. Journal of Catalysis, 254(2), 180-189. doi:10.1016/j.jcat.2007.12.005Epelde, E., Gayubo, A. G., Olazar, M., Bilbao, J., & Aguayo, A. T. (2014). Modified HZSM-5 zeolites for intensifying propylene production in the transformation of 1-butene. Chemical Engineering Journal, 251, 80-91. doi:10.1016/j.cej.2014.04.060Ibáñez, M., Epelde, E., Aguayo, A. T., Gayubo, A. G., Bilbao, J., & Castaño, P. (2017). 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Ethnic differences in out-of-hospital cardiac arrest among Middle Eastern Arabs and North African populations living in Qatar
Aims: There are very few studies comparing epidemiology and outcomes of out-of-hospital cardiac arrest (OHCA) in different ethnic groups. Previous ethnicity studies have mostly determined OHCA differences between African American and Caucasian populations. The aim of this study was to compare epidemiology, clinical presentation, and outcomes of OHCA between the local Middle Eastern Gulf Cooperation Council (GCC) Arab and the migrant North African populations living in Qatar. Methods: This was a retrospective cohort study of Middle Eastern GCC Arabs and migrant North African patients with presumed cardiac origin OHCA resuscitated by Emergency Medical Services (EMS) in Qatar, between June 2012 and May 2015. Results: There were 285 Middle Eastern GCC Arabs and 112 North African OHCA patients enrolled during the study period. Compared with the local GCC Arabs, univariate analysis showed that the migrant North African OHCA patients were younger and had higher odds of initial shockable rhythm, pre-hospital interventions (defibrillation and amioderone), pre-hospital scene time, and decreased odds of risk factors (hypertension, respiratory disease, and diabetes) and pre-hospital response time. The survival to hospital discharge had greater odds for North African OHCA patients which did not persist after adjustment. Multivariable logistic regression showed that North Africans were associated with lower odds of diabetes (OR 0.48, 95% CI 0.25–0.91, p = 0.03), and higher odds of initial shockable rhythm (OR 2.86, 95% CI 1.30–6.33, p = 0.01) and greater scene time (OR 1.02 95% CI 1.0–1.04, p = 0.02). Conclusions: North African migrant OHCA patients were younger, had decreased risk factors and favourable OHCA rhythm and received greater ACLS interventions with shorter pre-hospital response times and longer scene times leading to better survival.Peer reviewedFinal Accepted Versio
Molecular analysis distinguishes metastatic disease from second cancers in patients with retinoblastoma
The pediatric ocular tumor retinoblastoma readily metastasizes, but these lesions can masquerade as histologically similar pediatric small round blue cell tumors. Since 98% of retinoblastomas have RB1 mutations and a characteristic genomic copy number “signature”, genetic analysis is an appealing adjunct to histopathology to distinguish retinoblastoma metastasis from second primary cancer in retinoblastoma patients. Here, we describe such an approach in two retinoblastoma cases. In patient one, allele-specific (AS)-PCR for a somatic nonsense mutation confirmed that a temple mass was metastatic retinoblastoma. In a second patient, a rib mass shared somatic copy number gains and losses with the primary tumor. For definitive diagnosis, however, an RB1 mutation was needed, but heterozygous promoter→exon 11 deletion was the only RB1 mutation detected in the primary tumor. We used a novel application of inverse PCR to identify the deletion breakpoint. Subsequently, AS-PCR designed for the breakpoint confirmed that the rib mass was metastatic retinoblastoma. These cases demonstrate that personalized molecular testing can confirm retinoblastoma metastases and rule out a second primary cancer, thereby helping to direct the clinical management
Screening for pineal trilateral retinoblastoma revisited: a meta-analysis
Topic To determine until what age children are at risk for pineal trilateral retinoblastoma (TRb), whether its onset is linked to the age at which intraocular retinoblastomas develop, and the lead time from a detectable pineal TRb to symptoms. Clinical relevance About 45% of patients with retinoblastoma – those with a germline RB1 pathogenic variant – are at risk for pineal TRb. Early detection and treatment is essential for survival. Current evidence is unclear on the usefulness of screening for pineal TRb and, if useful, until what age screening should be continued. Methods We conducted a study according to the MOOSE guideline for reporting meta-analyses of observational studies. We searched PubMed and Embase between January 1, 1966, and February 27, 2019, for published literature. We considered articles reporting patients with TRb with survival and follow-up data. Inclusion of articles was performed separately and independently by two authors, and two authors also independently extracted the relevant data. They resolved discrepancies by consensus. Results One hundred thirty-eight patients with pineal TRb were included. Of 22 asymptomatic patients, 21 (95%) were diagnosed before the age of 40 months (median 16, interquartile range 9–29). Age at diagnosis of pineal TRb in patients diagnosed with retinoblastoma at ≤6 months versus >6 months of age were comparable (P=0.44), suggesting independency between the ages at diagnosis of intraocular retinoblastoma and pineal TRb. The laterality of intraocular retinoblastoma and its treatment were unassociated with the age when the pineal TRb was diagnosed. The lead time from an asymptomatic to a symptomatic pineal TRb was approximately 1 year. By performing a screening magnetic resonance imaging scan every 6 months after the diagnosis of heritable retinoblastoma (median age 6 months) until the age of 36 months, at least 311 and 776 scans would be required to detect one asymptomatic pineal TRb and to save one life, respectively. Conclusion Patients with retinoblastoma are at risk for pineal trilateral retinoblastoma for a shorter period than previously assumed and the age at diagnosis of pineal trilateral retinoblastoma is independent of the age at diagnosis of retinoblastoma. The GRADE level of evidence for these conclusions remains low.Peer reviewe
Asynchronous pineoblastoma is more likely after early diagnosis of retinoblastoma : a meta-analysis
Purpose To determine the risk of patients with an early diagnosis of heritable retinoblastoma being diagnosed with TRb (or pineoblastoma) asynchronously in a later stage and its effect on screening. Methods We updated the search (PubMed and Embase) for published literature as performed by our research group in 2014 and 2019. Trilateral retinoblastoma (TRb) patients were eligible for inclusion if identifiable as unique and the age at which TRb was diagnosed was available. The search yielded 97 new studies. Three new studies and eight new patients were included. Combined with 189 patients from the previous meta-analysis, the database included 197 patients. The main outcome was the percentage of asynchronous TRb in patients diagnosed before and after preset age thresholds of 6 and 12 months of age at retinoblastoma diagnosis. Results Seventy-nine per cent of patients with pineoblastoma are diagnosed with retinoblastoma before the age of 12 months. However, baseline MRI screening at time of retinoblastoma diagnosis fails to detect the later diagnosed pineal TRb in 89% of patients. We modelled that an additional MRI performed at the age of 29 months picks up 53% of pineoblastomas in an asymptomatic phase. The detection rate increased to 72%, 87% and 92%, respectively, with 2, 3 and 4 additional MRIs. Conclusions An MRI of the brain in heritable retinoblastoma before the age of 12 months misses most pineoblastomas, while retinoblastomas are diagnosed most often before the age of 12 months. Optimally timed additional MRI scans of the brain can increase the asymptomatic detection rate of pineoblastoma.Peer reviewe
Paediatric extracranial germ-cell tumours.
Management of paediatric extracranial germ-cell tumours carries a unique set of challenges. Germ-cell tumours are a heterogeneous group of neoplasms that present across a wide age range and vary in site, histology, and clinical behaviour. Patients with germ-cell tumours are managed by a diverse array of specialists. Thus, staging, risk stratification, and treatment approaches for germ-cell tumours have evolved disparately along several trajectories. Paediatric germ-cell tumours differ from the adolescent and adult disease in many ways, leading to complexities in applying age-appropriate, evidence-based care. Suboptimal outcomes remain for several groups of patients, including adolescents, and patients with extragonadal tumours, high tumour markers at diagnosis, or platinum-resistant disease. Survivors have significant long-term toxicities. The challenge moving forward will be to translate new insights from molecular studies and collaborative clinical data into improved patient outcomes. Future trials will be characterised by improved risk-stratification systems, biomarkers for response and toxic effects, rational reduction of therapy for low-risk patients and novel approaches for poor-risk patients, and improved international collaboration across paediatric and adult cooperative research groups.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/S1470-2045(15)00545-
Comparison of carboplatin versus cisplatin in the treatment of paediatric extracranial malignant germ cell tumours: A report of the Malignant Germ Cell International Consortium.
PURPOSE: To compare the outcomes of paediatric and adolescent extracranial malignant germ cell tumour (GCT) patients treated with either carboplatin or cisplatin on clinical trials conducted by the Children's Oncology Group (COG) and the Children's Cancer and Leukaemia Group (CCLG). METHODS: The Malignant Germ Cell International Consortium (MaGIC) has created a database of the GCT clinical trials conducted since 1983 by COG (United States, Canada and Australia), which used cisplatin-based regimens, and by CCLG (United Kingdom), which used carboplatin-based regimens. Using the parametric cure model, this study compared the overall 4-year event-free survival (EFS), stratified by age, stage, site and the a-priori defined MaGIC 'risk' groups: standard risk ((SR) 1 (EFS >80%; age 80%, age ≥ 11y) and poor risk (PR) (EFS ≤ 70%, age ≥ 11y). RESULTS: Cisplatin-based therapy was used in 620 patients; carboplatin was used in 163 patients. In the overall multivariate cure model, the two regimens did not differ significantly (cisplatin: 4-year EFS 86%; 95% confidence interval (CI) 83-89% versus carboplatin 4-year EFS 86%; 95% CI 79-90%; p = 0.87). No significant differences were noted in stratified analyses by site, stage, age and MaGIC risk groups: SR1 (p = 0.20), SR2 (p = 0.55) or PR (p = 0.72) patients. CONCLUSIONS: In these trials conducted contemporaneously, there is no significant difference in outcome observed overall, or any subset of patients, who were treated with regimens containing cisplatin versus carboplatin These results suggested sufficient equipoise to justify a randomised trial to evaluate the effectiveness of carboplatin versus cisplatin in the treatment of children, adolescents and young adults with standard risk GCT, which is currently underway