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1.
Earth Syst Environ ; 6(4): 917-926, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36185412

RESUMO

The government of Saudi Arabia imposed a strict lockdown between March and July 2020 to stop the spread of the coronavirus disease (COVID-19), which has led to a sharp decline in economic activities. The daily temporal variations of PM10, PM2.5, carbon monoxide (CO), nitrogen dioxide (NO2), and ozone (O3) were used to investigate the changes in air quality in response to COVID-19 lockdown control measures from January to December 2020 in Jeddah, Saudi Arabia. Meteorological parameters (wind speed, direction, temperature, relative humidity) were also analyzed to understand the changes during the pandemic. As a result, significant reductions in the concentrations of NO2 (- 44.5%), CO (- 41.5%), and PM2.5, PM10 (- 29.5%, each) were measured in the capital city of Jeddah during the quarantine compared to the pre-lockdown average. In contrast, the lockdown caused a significant increase in O3 by 41%. The changes in air quality during the COVID-19 outbreak by comparing the average pollutant concentration before lockdown (January 1-March 21, 2020) and the following 12 weeks during the partial lockdown (March 22-July 28, 2020), reveal a very significant decrease in pollutants, and consequently a significant improvement in air quality. Observed differences are attributable to changes in point source emissions associated with changes in localized activities, possibly related to decreased economic and industrial activity in response to the lockdown. The results of the present study show during the study period indicated a positive response to lockdown during the COVID-19 pandemic. Furthermore, the results can be used to establish future control measures and strategies to improve air quality.

2.
Sci Total Environ ; 810: 152046, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34856280

RESUMO

Plastic pollution and its impact on marine ecosystems are major concerns globally, and the situation was exacerbated after the outbreak of COVID-19. Clean-up campaigns took place during the summer season (June-August 2020) in two coastal cities in Egypt (Alexandria and Hurghada) and Jeddah, Saudi Arabia to document the abundance of beach debris through public involvement, and then remove it. A total of 3673, 255, and 848 items were collected from Alexandria, Hurghada, and Jeddah daily, respectively. Gloves and face masks (personal protective equipment "PPE") represent represented 40-60% of the total plastic items collected from each of the three cities, while plastic bags represented 7-20% of the total plastics litter collected from the same cities. The results indicated the presence of 2.79, 0.29, and 0.86 PPE item m-2 in Alexandria, Hurghada and Jeddah, respectively. This short focus provides an assessment of the environmental impacts of single-use gloves and masks used for COVID-19 protection from June to August 2020. To the best of our knowledge, this study presents the first such information from the Middle East, specifically Egypt and Saudi Arabia. It highlights the need for further knowledge and action, such as safe, sustainable, and transparent waste management processes related to COVID-19 to reduce the negative impacts now, as well as in future events. Furthermore, this study helps in achieving key components of the United Nation's Sustainable Development Goals (SDGs). This short focus can serve as a multipurpose document, not only for scientists of different disciplines but for social media and citizens in general.


Assuntos
COVID-19 , Equipamento de Proteção Individual , Ecossistema , Egito/epidemiologia , Humanos , Pandemias , Plásticos , SARS-CoV-2 , Arábia Saudita/epidemiologia
3.
Saudi J Kidney Dis Transpl ; 30(3): 710-714, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249238

RESUMO

Takayasu arteritis (TA) is a rare chronic granulomatous inflammatory arterial disease of unknown etiology that affects the aorta, its main branches and pulmonary artery. The clinical presentation is nonspecific, with signs and symptoms that vary according to the affected arterial segment. The most commonly affected vessel is the subclavian artery, while renal artery stenosis is relatively uncommon. We report a case of a 57-year-old male patient with late diagnosis of TA and various related complications including stroke in the left middle cerebral artery territory, predominant left renal artery stenosis, and hypertension with discrepancy of blood pressure between two arms due to predominant left subclavian artery stenosis. Thus, physicians should keep in their mind this late presentation after the age of 40 years. The aim is to increase the awareness of this condition because of early diagnosis and the timely introduction of treatment can lead to improved outcomes in this poorly understood clinical enigma.


Assuntos
Infarto da Artéria Cerebral Média/etiologia , Obstrução da Artéria Renal/etiologia , Arterite de Takayasu/complicações , Fármacos Cardiovasculares/uso terapêutico , Glucocorticoides/uso terapêutico , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Obstrução da Artéria Renal/diagnóstico por imagem , Obstrução da Artéria Renal/tratamento farmacológico , Arterite de Takayasu/diagnóstico por imagem , Arterite de Takayasu/tratamento farmacológico , Resultado do Tratamento
4.
Appl Environ Microbiol ; 79(12): 3582-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23542629

RESUMO

In recent years, glycerol has become an attractive carbon source for microbial processes, as it accumulates massively as a by-product of biodiesel production, also resulting in a decline of its price. A potential use of glycerol in biotechnology is the synthesis of poly(3-hydroxypropionate) [poly(3HP)], a biopolymer with promising properties which is not synthesized by any known wild-type organism. In this study, the genes for 1,3-propanediol dehydrogenase (dhaT) and aldehyde dehydrogenase (aldD) of Pseudomonas putida KT2442, propionate-coenzyme A (propionate-CoA) transferase (pct) of Clostridium propionicum X2, and polyhydroxyalkanoate (PHA) synthase (phaC1) of Ralstonia eutropha H16 were cloned and expressed in the 1,3-propanediol producer Shimwellia blattae. In a two-step cultivation process, recombinant S. blattae cells accumulated up to 9.8% ± 0.4% (wt/wt [cell dry weight]) poly(3HP) with glycerol as the sole carbon source. Furthermore, the engineered strain tolerated the application of crude glycerol derived from biodiesel production, yielding a cell density of 4.05 g cell dry weight/liter in a 2-liter fed-batch fermentation process.


Assuntos
Biotecnologia/métodos , Enterobacteriaceae/metabolismo , Glicerol/metabolismo , Ácido Láctico/análogos & derivados , Polímeros , Álcool Desidrogenase/genética , Aldeído Desidrogenase/genética , Engenharia Celular/métodos , Enterobacteriaceae/genética , Escherichia coli , Vetores Genéticos/genética , Ácido Láctico/biossíntese , Pseudomonas putida/enzimologia
5.
AMB Express ; 2(1): 59, 2012 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-23164136

RESUMO

Isolation of polyhydroxyalkanoates (PHAs) from bacterial cell matter is a critical step in order to achieve a profitable production of the polymer. Therefore, an extraction method must lead to a high recovery of a pure product at low costs. This study presents a simplified method for large scale poly(3-hydroxybutyrate), poly(3HB), extraction using sodium hypochlorite. Poly(3HB) was extracted from cells of Ralstonia eutropha H16 at almost 96% purity. At different extraction volumes, a maximum recovery rate of 91.32% was obtained. At the largest extraction volume of 50 L, poly(3HB) with an average purity of 93.32% ± 4.62% was extracted with a maximum recovery of 87.03% of the initial poly(3HB) content. This process is easy to handle and requires less efforts than previously described processes.

6.
J Water Health ; 7(3): 380-91, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19491490

RESUMO

Diarrhoeal disease is still one of the major causes of mortality and morbidity of children in developing countries. Our objective was to assess the prevalence of diarrhoeal disease among male schoolchildren in Jeddah and to identify the associated risk factors, especially those related to drinking water and sanitation disposal. This cross-sectional study was conducted randomly where self-administered questionnaires were issued to parents through the schools. The data were collected from 1,064 respondents indicating that 14.9% of the children had diarrhoea during the previous month. The main risk factors were: the number of children under five years living in the same house (OR per child 1.34, 95% confidence intervals 1.15-1.56), being of Saudi nationality (OR 1.75, 1.08-2.84), reporting sewage spillage near the home (OR 1.69, 1.14-2.53), eating out after school hours (OR 1.74, 1.16-2.60), not drying hands after washing them (OR 1.66, 1.10-2.51), using reusable cloths or sponges to dry dishes (OR 1.70, 1.14-2.52).


Assuntos
Diarreia/epidemiologia , Exposição Ambiental/efeitos adversos , Saúde Pública , Abastecimento de Água , Criança , Estudos Transversais , Humanos , Masculino , Prevalência , Fatores de Risco , Saneamento , Arábia Saudita/epidemiologia , Fatores Socioeconômicos
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