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Saudi J Biol Sci ; 27(12): 3181-3186, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33052188

RESUMO

Face masks are primary line of defense to reduce the transmission risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). World Health Organization (WHO) has already updated the guidelines and advised the use of face masks in public areas essentially. This has dramatically increased the production and use of face masks in many parts of the world. Arabian Peninsula is comprised of six countries where the public perception of following WHO guidelines is high. In this study, we highlight the concerns relating to extensive use of face masks in this region, particularly in the context of (micro-)plastic pollution. We computed the number of face masks to be used in each of the countries of Arabian Peninsula for varying levels of acceptance rate and average number of daily usages. Accordingly, the amount of (micro-)plastic that could come into the terrestrial and marine environment is also reported. Saudi Arabia, being the most populated country in the region may contribute up to 32-235 thousand tons of (micro-)plastic which is nearly half of the amount in the whole Peninsula. On the other hand, an extremely high infection rate in Qatar (25.74%) may also lead to a significant increase of (micro-)plastic content due to high public acceptance rate and living standards. The high (micro-)plastic fraction is of significant concern because it ends up in the marine ecosystems. Further, it allows colonization of several pathogenic microorganisms (bacteria, viruses, fungal filaments, and spores) and might serve as carriers of disease transmission finally affecting the living organisms habituating these ecosystems. It is suggested that appropriate regulations on face masks waste should be devised to avoid any unwanted consequences in the near future.

3.
Enzyme Microb Technol ; 131: 109385, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31615674

RESUMO

From ecological and industrial perspectives, Anoxybacillus flavithermus species that lives in a thermophilic environment, are extremely important bacteria due to their potential in producing highly interesting compounds and enzymes. In order to understand the genetic makeup of these thermophiles, we have performed a comparative genomics study of 12 genome-sequenced strains of Anoxybacillus flavithermus bacteria. The genome size of Anoxybacillus flavithermus strains is from 2.5Mbp to 3.7Mbp and on average containing a low percentage of G + C genomic content (˜41.9%). We show that, on the basis of the total gene-content, Anoxybacillus flavithermus strains are grouped in three different subgroups. In the future, it would be interesting to explore these strain subgroups to further understand the lifestyle of thermophilic bacteria. Focussing on the Anoxybacillus flavithermus AK1 strain, which was isolated from a Hot Spring in Saudi Arabia and closely related to A. flavithermus NBRC strain, we identified a unique list of 75 genes specific to AK1 strain, of which 63 of them have homologs in other taxonomically related species. We speculate that these AK1-specific genes might be resulted due to horizontal gene transfer from other bacteria in order to adapt to the extreme environmental conditions. Moreover, we predicted three potential secondary metabolite gene clusters in the AK1 strain that further need to be experimentally characterised. Genomic annotation, secondary metabolite gene clusters and outcomes of the strain genomic comparisons from this study would be the basis for the strain-specific mathematical model for exploiting the metabolism for the industrial and ecological applications.


Assuntos
Anoxybacillus/genética , Genoma Bacteriano , Genômica , Anoxybacillus/isolamento & purificação , Composição de Bases , Genótipo , Fontes Termais , Arábia Saudita
4.
Biomed Res Int ; 2018: 5862437, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29992154

RESUMO

Brevibacillus borstelensis AK1 is a thermophile which grows between the temperatures of 45°C and 70°C. The present study is an extended genome report of B. borstelensis AK1 along with the morphological characterization. The strain is isolated from a hot spring in Saudi Arabia (southeast of the city Gazan). It is observed that the strain AK1 is rod-shaped, motile, and strictly aerobic bacterium. The whole genome sequence resulted in 29 contigs with a total length of 5,155,092 bp. In total, 3,946 protein-coding genes and 139 RNA genes were identified. Comparison with the previously submitted strains of B. borstelensis strains illustrates that strain AK1 has a small genome size but high GC content. The strain possesses putative genes for degradation of a wide range of substrates including polyethylene (plastic) and long-chain hydrocarbons. These genomic features may be useful for future environmental/biotechnological applications.


Assuntos
Brevibacillus/genética , Sequenciamento Completo do Genoma , Composição de Bases , Fontes Termais , Arábia Saudita
5.
Eur J Pediatr Surg ; 17(6): 428-30, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18072031

RESUMO

Malignant schwannoma (malignant peripheral nerve sheath tumour, MPNST) is a rare high-grade tumour arising from peripheral nerves. We report the case of a 3-year-old male who presented with a non-tender lesion on the dorsum of his penis. The lesion was excised and a formal circumcision performed. Histology of the lesion revealed a spindle cell tumour. Immunohistochemistry showed the tumour cells to be strongly positive for S100 and Vimentin. A diagnosis of intermediate grade malignant peripheral nerve sheath tumour was made. Malignant schwannoma is rare in children and is previously unreported in the penis in the paediatric age group without evidence of neurofibromatosis.


Assuntos
Neurilemoma/diagnóstico , Neurofibromatoses/diagnóstico , Neoplasias Penianas/diagnóstico , Biomarcadores Tumorais/metabolismo , Pré-Escolar , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Masculino , Neurilemoma/metabolismo , Neurilemoma/cirurgia , Neoplasias Penianas/metabolismo , Neoplasias Penianas/cirurgia , Proteínas S100/metabolismo , Procedimentos Cirúrgicos Urológicos Masculinos/métodos
6.
J Pediatr Urol ; 13(1): 57.e1-57.e5, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27670783

RESUMO

INTRODUCTION: Anogenital distance (AGD) is a recognised marker of in utero androgen action. OBJECTIVE: This study aimed to evaluate the relationship between severity of hypospadias and AGD. STUDY DESIGN: Boys undergoing hypospadias repair in a single tertiary centre between May 2012 and February 16 were included in the study. Anogenital distance was measured from the centre of the anus to the base of the penis, and anoscrotal distance (ASD) from the centre of the anus to the junction between the smooth perineal skin and scrotal skin. Trained paediatric urologists made all measurements using digital callipers. RESULTS: Fifty-nine boys with hypospadias and 31 age-matched controls undergoing circumcision (median age 1.37 years, range 1.01-1.96) had AGD and ASD measured under anaesthetic. The patients were divided into two groups, according to hypospadias severity: group 1 - distal penile/subcoronal/glandular (n = 40); and group 2 - perineal/penoscrotal/midshaft (n = 19). The median AGD for controls was 74.0 mm (range 53.2-87.8) and for hypospadias it was 72.3 mm (range 50.7-90.0) (P = 0.816). The median ASD for controls was 42.3 mm (range 31.0-56.1) and for hypospadias it was 39.4 mm (range 20.7-77.0) (P = 0.224). Considering severity of hypospadias, the median AGD for group 1 and group 2 was 73.7 mm (range 50.7-90.0) and 63.3 mm (range 53.6-77.0), respectively (P < 0.001). The median ASD was also higher in group 1, at 41.3 mm (range 20.7-65.0), compared to 35.2 mm (range 23.5-77.0) in group 2 (P = 0.119) (Summary Fig.). DISCUSSION: This study showed that more severe forms of hypospadias are associated with shorter AGD and ASD. These findings agree with two previous studies that identified reduced AGD in boys with hypospadias. However, these studies did not investigate an association with severity of hypospadias. As hypospadias is multifactorial, only a small proportion of cases are thought to be associated with impaired in utero androgen exposure. The shorter AGD in boys with severe hypospadias compared with mild hypospadias would indicate that AGD is a marker of the severity of androgen production. This may also suggest that less severe forms of hypospadias have a different aetiology involving a later stage of development, and that they are not the result of reduced androgen exposure in the male programming window between the 8-14 weeks gestation. CONCLUSION: This study identified that boys with more severe hypospadias are more likely to have a shorter AGD and ASD than boys with mild hypospadias. This may indicate that there is a more profound impairment of in utero androgen action in severe hypospadias.


Assuntos
Hipospadia/diagnóstico , Hipospadia/cirurgia , Períneo/anatomia & histologia , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Canal Anal , Estudos de Casos e Controles , Circuncisão Masculina/métodos , Humanos , Lactente , Masculino , Pênis , Cuidados Pré-Operatórios , Estudos Prospectivos , Valores de Referência , Medição de Risco , Escroto , Índice de Gravidade de Doença , Resultado do Tratamento , Pesos e Medidas
8.
Bioinorg Chem Appl ; 2013: 458943, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23606820

RESUMO

Water disinfection has attracted the attention of scientists worldwide due to water scarcity. The most significant challenges are determining how to achieve proper disinfection without producing harmful byproducts obtained usually using conventional chemical disinfectants and developing new point-of-use methods for the removal and inactivation of waterborne pathogens. The removal of contaminants and reuse of the treated water would provide significant reductions in cost, time, liabilities, and labour to the industry and result in improved environmental stewardship. The present study demonstrates a new approach for the removal of Escherichia coli (E. coli) from water using as-produced and modified/functionalized carbon nanotubes (CNTs) with 1-octadecanol groups (C18) under the effect of microwave irradiation. Scanning/transmission electron microscopy, thermogravimetric analysis, and FTIR spectroscopy were used to characterise the morphological/structural and thermal properties of CNTs. The 1-octadecanol (C18) functional group was attached to the surface of CNTs via Fischer esterification. The produced CNTs were tested for their efficiency in destroying the pathogenic bacteria (E. coli) in water with and without the effect of microwave radiation. A low removal rate (3-5%) of (E. coli) bacteria was obtained when CNTs alone were used, indicating that CNTs did not cause bacterial cellular death. When combined with microwave radiation, the unmodified CNTs were able to remove up to 98% of bacteria from water, while a higher removal of bacteria (up to 100%) was achieved when CNTs-C18 was used under the same conditions.

10.
Phys Chem Chem Phys ; 9(10): 1247-54, 2007 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-17325771

RESUMO

We studied computationally the activation of H(2) on clean planar (111), (110) and stepped (221) as well as oxygen pre-covered silver surfaces using a density functional slab model approach. In line with previous data we determined clean silver to be inert towards H(2) dissociation, both thermodynamically and kinetically. The reaction is endothermic by approximately 40 kJ mol(-1) and exhibits high activation energies of approximately 125 kJ mol(-1). However, oxygen on the surface, modeled by the reconstructed surface p(2 x 1)O/Ag(110) that exhibits -O-Ag-O- added rows, renders H(2) dissociation clearly exothermic and kinetically feasible. The reaction was calculated to proceed in two steps: first the H-H bond is broken at an Ag-O pair with an activation barrier E(a) approximately 70 kJ mol(-1), then the H atom bound at an Ag center migrates to a neighboring O center with E(a) approximately 12 kJ mol(-1).

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