Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Heliyon ; 9(2): e12501, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36816281

RESUMO

Climate is a vital factor that shapes habitat suitability for many species across space and time. Gazella subgutturosa (Goitered gazelle) is a globally vulnerable mammal already extinct in some areas of Armenia and Georgia and is highly threatened in other areas of its distribution. In this study, new data were gathered for 33 locations in north-eastern Iraq, and then together with literature data, Species Distribution Models (SDMs) were used to explore the geographical distribution of the gazelle under current and future climate change scenarios. We studied the relationship between seven climate variables and 43 occurrence records to predict habitat suitability of the gazelle under the current climate, and also under four future climate scenarios (RCP2.6 and RCP8.5 for both 2050 and 2080). Annual precipitation and isothermality had the most influence on the distribution of Gazella subgutturosa. The most suitable habitat in both the current and future scenarios was located in north-eastern Iraq close to the Iranian border near the Zagros Mountains. There was no difference in habitat suitability for the gazelle inside Iraqi Protected Areas (PAs) compared to outside the PAs. Using the occurrence records and IUCN Red List national assessments, we found Iraqi Goitered gazelle populations to be classified as Endangered (EN). Our results suggest urgent conservation planning is needed to save this species, including the establishment of new PAs. These results contribute new baseline information, which was currently missing Goitered gazelle in about Iraq, to the IUCN SSC Antelope Specialist Group, which will hopefully aid with future global assessments and conservation.

2.
ACS Appl Mater Interfaces ; 13(47): 55953-55965, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34788015

RESUMO

The threat of antibiotic-resistant bacteria is an ever-increasing problem in public health. In this report, we examine the photochemical properties with a proof-of-principle biocidal assay for a novel series of regio-regular imidazolium derivative poly-(3-hexylthiophene)/sodium dodecyl sulfate (P3HT-Im/SDS) materials from ultrafast sub-ps dynamics to µs generation of reactive oxygen species (ROS) and 30 min biocidal reactivity with Escherichia coli (E. coli). This broad series encompassing pure P3HT-Im to cationic, neutral, and anionic P3HT-Im/SDS materials are all interrogated by a variety of techniques to characterize the physical material structure, electronic structure, and antimicrobial activity. Our results show that SDS complexation with P3HT-Im results in aggregate materials with reduced ROS generation and light-induced anti-microbial activity. However, our characterization reveals that the presence of non-aggregated or lightly SDS-covered polymer segments is still capable of ROS generation. Full encapsulation of the P3HT-Im polymer completely deactivates the light killing pathway. High SDS concentrations, near and above critical micelle concentration, further deactivate all anti-microbial activity (light and dark) even though the P3HT-Im regains its electronic properties to generate ROS.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Polieletrólitos/farmacologia , Polímeros/farmacologia , Dodecilsulfato de Sódio/farmacologia , Tiofenos/farmacologia , Antibacterianos/química , Escherichia coli/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Tamanho da Partícula , Processos Fotoquímicos , Polieletrólitos/química , Polímeros/química , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Dodecilsulfato de Sódio/química , Propriedades de Superfície , Tiofenos/química
3.
Photochem Photobiol ; 94(6): 1116-1123, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30222200

RESUMO

Cationic polythiophenes have been shown to be potent antimicrobial compounds due to their ability to absorb visible light and sensitize the production of reactive oxygen species (ROS) as well as their ability to selectively associate with and damage negatively charged cell envelopes. This study demonstrates the ability of differentially sized imidazolium- and tertiary amine-functionalized poly(3-hexylthiophene) (P3HT) to inactivate Gram-negative Escherichia coli and Gram-positive Bacillus atrophaeus under photolysis and dark conditions. Flow cytometry viability assays are used to quantify cell death. Each compound shows high levels of killing at both 1 and 10 µg mL-1 polymer concentrations for each microbial species after photoactivation as well as high levels of dark inactivation in many cases. Tertiary amine-functionalized P3HT is shown to have different killing patterns, shown by transmission electron microscopy, compared to the imidazolium-functionalized derivatives.


Assuntos
Antibacterianos/química , Bacillus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fármacos Fotossensibilizantes/química , Tiofenos/química , Aminas/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bacillus/química , Bacillus/crescimento & desenvolvimento , Cátions , Escherichia coli/química , Escherichia coli/crescimento & desenvolvimento , Imidazóis/química , Luz , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Fotólise , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Polimerização , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Tiofenos/síntese química , Tiofenos/farmacologia
4.
Saudi Med J ; 35 Suppl 1: S36-43, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25551110

RESUMO

OBJECTIVE: To describe cases of sirenomelia and severe caudal regression syndrome (CRS), to report the prevalence of sirenomelia, and compare our findings with the literature. METHODS: Retrospective data was retrieved from the medical records of infants with the diagnosis of sirenomelia and CRS and their mothers from 1989 to 2010 (22 years) at the Security Forces Hospital, Riyadh, Saudi Arabia. A perinatologist, neonatologist, pediatric neurologist, and radiologist ascertained the diagnoses. The cases were identified as part of a study of neural tube defects during that period. A literature search was conducted using MEDLINE. RESULTS: During the 22-year study period, the total number of deliveries was 124,933 out of whom, 4 patients with sirenomelia, and 2 patients with severe forms of CRS were identified. All the patients with sirenomelia had single umbilical artery, and none were the infant of a diabetic mother. One patient was a twin, and another was one of triplets. The 2 patients with CRS were sisters, their mother suffered from type II diabetes mellitus and morbid obesity on insulin, and neither of them had a single umbilical artery. Other associated anomalies with sirenomelia included an absent radius, thumb, and index finger in one patient, Potter's syndrome, abnormal ribs, microphthalmia, congenital heart disease, hypoplastic lungs, and diaphragmatic hernia. CONCLUSION: The prevalence of sirenomelia (3.2 per 100,000) is high compared with the international prevalence of one per 100,000. Both cases of CRS were infants of type II diabetic mother with poor control, supporting the strong correlation of CRS and maternal diabetes.


Assuntos
Anormalidades Múltiplas/epidemiologia , Ectromelia/epidemiologia , Meningocele/epidemiologia , Complicações na Gravidez , Região Sacrococcígea/anormalidades , Anormalidades Múltiplas/classificação , Anormalidades Múltiplas/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Ectromelia/classificação , Ectromelia/diagnóstico , Feminino , Humanos , Recém-Nascido , Masculino , Meningocele/classificação , Meningocele/diagnóstico , Gravidez , Prevalência , Estudos Retrospectivos , Arábia Saudita/epidemiologia
5.
Saudi Med J ; 35 Suppl 1: S49-56, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25551112

RESUMO

OBJECTIVE: To ascertain the incidence, and describe the various forms of neural tube defects (NTDs) due to genetic, chromosomal, and syndromic causes. METHODS: We carried out a retrospective analysis of data retrieved from the medical records of newborn infants admitted to the Neonatal Intensive Care Unit with NTDs and their mothers spanning 14 years (1996-2009) at the Security Forces Hospital, Riyadh, Saudi Arabia. The cases were ascertained by a perinatologist, neonatologist, geneticist, radiologist, and neurologist. The literature was reviewed via a MEDLINE search. Only liveborn babies were included. Permission from the Educational Committee at the Security Forces Hospital was obtained prior to the collection of data. RESULTS: Out of 103 infants with NTDs admitted during this period, 20 (19.4%) were found to have an underlying genetic syndromic, chromosomal and/or other anomalies. There were 5 cases of Meckel-Gruber syndrome, 2 Joubert syndrome, one Waardenburg syndrome, one Walker-Warburg syndrome, 2 chromosomal disorders, 2 caudal regression, one amniotic band disruption sequence, one associated with omphalocele, one with diaphragmatic hernia, and 4 with multiple congenital anomalies. CONCLUSION: There is a high rate of underlying genetic syndromic and/or chromosomal causes of NTDs in the Saudi Arabian population due to the high consanguinity rate. Identification of such association can lead to more accurate provisions of genetic counseling to the family including preimplantation genetic diagnosis or early termination of pregnancies associated with lethal conditions.


Assuntos
Aberrações Cromossômicas , Defeitos do Tubo Neural/genética , Transtornos da Motilidade Ciliar/genética , Consanguinidade , Encefalocele/genética , Feminino , Humanos , Recém-Nascido , Masculino , Doenças Renais Policísticas/genética , Retinose Pigmentar , Estudos Retrospectivos , Síndrome
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA