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3.
Astron Astrophys ; 6472021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34257461

RESUMO

CONTEXT: For all the amides detected in the interstellar medium (ISM), the corresponding nitriles or isonitriles have also been detected in the ISM, some of which have relatively high abundances. Among the abundant nitriles for which the corresponding amide has not yet been detected is cyanoacetylene (HCCCN), whose amide counterpart is propiolamide (HCCC(O)NH2). AIMS: With the aim of supporting searches for this amide in the ISM, we provide a complete rotational study of propiolamide from 6 GHz to 440 GHz. METHODS: Time-domain Fourier transform microwave (FTMW) spectroscopy under supersonic expansion conditions between 6 GHz and 18 GHz was used to accurately measure and analyze ground-state rotational transitions with resolved hyperfine structure arising from nuclear quadrupole coupling interactions of the 14N nucleus. We combined this technique with the frequency-domain room-temperature millimeter wave and submillimeter wave spectroscopies from 75 GHz to 440 GHz in order to record and assign the rotational spectra in the ground state and in the low-lying excited vibrational states. We used the ReMoCA spectral line survey performed with the Atacama Large Millimeter/submillimeter Array toward the star-forming region Sgr B2(N) to search for propiolamide. RESULTS: We identified and measured more than 5500 distinct frequency lines of propiolamide in the laboratory. These lines were fitted using an effective semi-rigid rotor Hamiltonian with nuclear quadrupole coupling interactions taken into consideration. We obtained accurate sets of spectroscopic parameters for the ground state and the three low-lying excited vibrational states. We report the nondetection of propiolamide toward the hot cores Sgr B2(N1S) and Sgr B2(N2). We find that propiolamide is at least 50 and 13 times less abundant than acetamide in Sgr B2(N1S) and Sgr B2(N2), respectively, indicating that the abundance difference between both amides is more pronounced by at least a factor of 8 and 2, respectively, than for their corresponding nitriles. CONCLUSIONS: Although propiolamide has yet to be included in astrochemical modeling networks, the observed upper limit to the ratio of propiolamide to acetamide seems consistent with the ratios of related species as determined from past simulations. The comprehensive spectroscopic data presented in this paper will aid future astronomical searches.

4.
J Hosp Infect ; 112: 96-103, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33839212

RESUMO

BACKGROUND: Gram-negative organisms harbouring carbapenem resistance genes (CRGs) are spreading globally, including in Gulf Cooperation Council (GCC) countries. However, relatively few data are available about carriage of CRGs in hospitalized patients in this region. AIM: To determine prevalence of CRG carriage and risk factors for colonization among patients in GCC hospitals. METHODS: Rectal swabs were obtained from ∼50 intensive care unit (ICU) patients from each of 11 hospitals in five GCC countries between March and November 2019. The swabs were tested for the presence of blaKPC, blaNDM, blaVIM, blaIMP, and blaOXA-48 CRG using a commercial polymerase chain reaction test. Data on risk factors for colonization were collected and analysed. FINDINGS: Of 529 specimens screened, 138 (26.1%) were positive for one or more CRGs. The positivity rates among the hospitals ranged from 8.0% to 67.3%; ∼20% of the positive specimens harboured ≥2 CRGs. The most common CRG detected was blaOXA-48, which was present in 82 specimens (15.5%). Additional CRGs included blaNDM, blaVIM, blaKPC, and blaIMP either alone or in combination. Overall, 31.1% of patients on antibiotics on admission to the ICU were positive for CRGs compared to 16.5% not on antibiotic therapy (P < 0.001). CRG detection was also more common among patients aged >65 years (P = 0.027) and increased with hospital length of stay (P = 0.025). CONCLUSION: The rate of CRGs detected in hospitalized patients in GCC countries varied considerably. Prior antibiotic exposure, increasing age, and prolonged length of stay were associated with CRG detection.


Assuntos
Proteínas de Bactérias , beta-Lactamases , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Hospitais , Humanos , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
5.
Astron Astrophys ; 644: A102, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33594292

RESUMO

CONTEXT: S-methyl thioformate CH3SC(O)H is a monosulfur derivative of methyl formate, a relatively abundant component of the interstellar medium (ISM). S-methyl thioformate being, thermodynamically, the most stable isomer, it can be reasonably proposed for detection in the ISM. AIMS: This work aims to experimentally study and theoretically analyze the ground and first torsional excited states for CH3SC(O)H in a large spectral range for astrophysical use. METHODS: S-methyl thioformate was synthesized as a result of a reaction of methyl mercaptan with acetic-formic anhydride. The millimeter-wave spectrum was then recorded for the first time from 150 to 660 GHz with the solid-state spectrometer located at Lille. RESULTS: A set of 3545 lines is determined and combined with 54 previously measured lines in the microwave region, belonging to ground state ν t = 0 as well as 1391 transitions in the first excited state of torsion ν 18 = 1. Some 164 lines were also assigned to ν 18 = 2 for the A-species. A global fit was performed using the BELGI-Cs code taking into account the large splitting of A and E lines due to methyl internal rotation motion with a relatively low barrier, V3 = 127.4846(15) cm-1. CONCLUSIONS: Using our spectroscopy work, a deep search of S-methyl thioformate was carried out in the IRAM 30m and ALMA data of different high-mass star-forming regions (Orion KL and Sgr B2). We derived an upper limit to the CH3SC(O)H column density in these regions.

6.
J Chem Phys ; 151(19): 194302, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31757131

RESUMO

Methoxyphenols (MPs) are a significant component of biomass burning emissions which mainly exists in our atmosphere in the gas phase where they contribute to the formation of secondary organic aerosols (SOAs). Rovibrational spectroscopy is a promising tool to monitor atmospheric MPs and infer their role in SOA formation. In this study, we bring a new perspective on the rovibrational analysis of MP isomers by taking advantage of two complementary devices combining jet-cooled environments and absorption spectroscopy: the Jet-AILES and the SPIRALES setups. Based on Q-branch frequency positions measured in the Jet-AILES Fourier-transform infrared (FTIR) spectra and guided by quantum chemistry calculations, we propose an extended vibrational and conformational analysis of the different MP isomers in their fingerprint region. Some modes such as far-IR out-of-plane -OH bending or mid-IR in-plane -CH bending allow us to assign individually all the stable conformers. Finally, using the SPIRALES setup with three different external cavity quantum cascade laser sources centered on the 930-990 cm-1 and the 1580-1690 cm-1 ranges, it was possible to proceed to the rovibrational analysis of the ν18 ring in-plane bending mode of the MP meta isomer providing a set of reliable excited state parameters, which confirms the correct assignment of two conformers. Interestingly, the observation of broad Q-branches without visible P- and R-branches in the region of the C-C ring stretching bands was interpreted as being probably due to a vibrational perturbation. These results highlight the complementarity of broadband FTIR and narrowband laser spectroscopic techniques to reveal the vibrational conformational signatures of atmospheric compounds over a large infrared spectral range.

7.
J Chem Phys ; 150(10): 104303, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30876373

RESUMO

Because methoxyphenols (MP) are emitted in significant quantities during biomass fires and contribute to the secondary organic aerosols formation which impacts the climate, their gas phase monitoring in the atmosphere is crucial and requires accurate rovibrational cross sections determined with a good knowledge of their ground state (GS) and vibrationally excited state (ES) molecular parameters. Therefore, the rotational spectra of the two isomers, 2-MP (guaïacol) and 4-MP (mequinol), have been measured in absorption and in emission at room temperature using a frequency multiplication chain and a mm-wave Fourier transform chirped-pulse spectrometer, respectively. Guided by quantum chemistry calculations, the conformational landscape has been characterised and the observation of only one rotamer in the spectra of 2-MP and 4-MP has been explained. For 2-MP, the most stable conformation is justified by an intramolecular O-H⋯OCH3 hydrogen-bond which has been characterised by a topology analysis of the electron density. In a global fit including more than 30 000 line assignments, rotational and quartic centrifugal constants of the GS and the three lowest energy ES have been determined allowing to reproduce the millimeter-wave spectra at the experimental accuracy. The same work has been performed on the cis-rotamer of 4-MP highlighting some perturbations marring the fit quality for two vibrationally ES. Finally, the isomeric dependence of the negative inertial defect ΔI agrees with that of the lowest energy out of plane mode ν45, and the variation of ΔI with the degree of vibrational excitation allows a fine estimation of v45 = 1 vibrational wavenumber.

8.
Asian Pac J Cancer Prev ; 19(7): 1917-1925, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-30051673

RESUMO

Breast and cervical cancers are global health concerns and major cause of deaths among women. Current treatments such as chemotherapy are associated with several drawbacks that limit their effectiveness. Several anticancer remedies have been found with natural products in the past and the search continues for more examples. Cytotoxic natural compounds may have considerable benefits for cancer therapy either in potentiating the impact of chemotherapy or curtailment of harmful effects. Therefore, discovery and identification of new drugs for breast and cervical cancer treatment are of high priority. The present study addressed the potential role of the ALD (Aucklandia lappa Decne) in suppressing proliferation of T-47D, HeLa and HEp-2 cells in comparison with the non-cancer HCC1937 BL cell line. Treatment with an ALD extract of T-47D, HeLa, and HEp-2 cells resulted in reduction in cell viability in MMT assays. Furthermore, lyophilized ALD principally suppressed cancer cell line growth and proliferation through induction of either intrinsic or extrinsic apoptotic pathways as demonstrated by significantly suppressed release of LDH, and NO production in a dose-dependent manner, and activation of death receptors in T-47D and HeLa cells but not the HEp-2 cell line. Interestingly, lyophilized ALD significantly (p<0.005) repressed the growth of HEp-2 and T-47D cells after treatment for 48hrs while 24hrs treatment significantly suppressed T-47D and HeLa cells. We report for the first time that lyophilized ALD selectively influences apoptosis through alternative apoptotic pathways in both breast and cervical human cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Etanol/química , Extratos Vegetais/farmacologia , Saussurea/química , Neoplasias do Colo do Útero/patologia , Adulto , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/tratamento farmacológico , Adulto Jovem
9.
Genet Mol Res ; 15(2)2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27173197

RESUMO

Toll-like receptors (TLRs) are essential elements of the innate immune response to different infections including the infection with human immunodeficiency virus (HIV). Single nucleotide polymorphisms (SNPs) in TLRs such as TLR4 1063A/G and 1363C/T have been found to be associated with changes in CD4 count, viral load (VL), and disease progression during HIV infection. However, the association of these SNPs with the pathogenesis during HIV infection is controversial. We investigated the frequency of TLR4 1063A/G and 1363C/T SNPs in 168 Omani donors [68 HIV-infected patients (>3% of Omani HIV-infected patients) and 100 healthy controls] and the association of these SNPs with the VL, CD8 and CD4 counts, and the immune recovery after cART as observed by CD4 T cell increase. SNPs were analyzed after the amplification of the regions that contain them by polymerase chain reaction (PCR) and sequencing of the PCR products. The TLR4 1063GG genotype was detected in the HIV-infected group only. No association was found between the studied SNPs and the average VL during 1 year of infection, the average CD4 and CD8 count during 1 year of viremia, the nadir CD4 count, the CD4 count when the patient reached VL < 50 copies/mL due to cART, and the ratio of the CD4 count 3 and 6 months after reaching VL < 50 copies/mL after cART to the last CD4 count before reaching VL < 50 copies/mL. Our study suggests that TLR4 (1063A/G and 1363C/T) SNPs have no association with the VL or the CD4 and CD8 counts during HIV infection.


Assuntos
Infecções por HIV/genética , Polimorfismo de Nucleotídeo Único , Receptor 4 Toll-Like/genética , Adulto , Contagem de Linfócito CD4 , Relação CD4-CD8 , Estudos de Casos e Controles , Feminino , Infecções por HIV/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Omã , Carga Viral
10.
J Chem Phys ; 144(2): 024303, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26772567

RESUMO

Methacrolein is a major oxidation product of isoprene emitted in the troposphere. New spectroscopy information is provided with the aim to allow unambiguous identification of this complex molecule, characterized by a large amplitude motion associated with the methyl top. State-of-the-art millimeter-wave spectroscopy experiments coupled to quantum chemical calculations have been performed. For the most stable s-trans conformer of atmospheric interest, the torsional and rotational structures have been characterized for the ground state, the first excited methyl torsional state (ν27), and the first excited skeletal torsional state (ν26). The inverse sequence of A and E tunneling sub-states as well as anomalous A-E splittings observed for the rotational lines of v26 = 1 state clearly indicates a coupling between methyl torsion and skeletal torsion. A comprehensive set of molecular parameters has been obtained. The far infrared spectrum of Durig et al. [Spectrochim. Acta, Part A 42, 89-103 (1986)] was reproduced, and a Fermi interaction between ν25 and 2ν27 was evidenced.

11.
East Mediterr Health J ; 20(10): 614-22, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25356692

RESUMO

Routine HIV testing of all pregnant women in Oman has been introduced without prior knowledge of women's attitudes towards testing or their behaviour in the event of a positive test. This study recruited 1000 Omani pregnant women from antenatal clinics to explore their knowledge of HIV/AIDS, attitudes towards HIV testing and intended behaviours in the event of a positive test. Mother-to-child transmission was recognized by 86.6% of the women but only 21.0% knew that it was preventable and a few acknowledged the important role of antiviral drugs. Half of the women (51.9%) reported having been tested for HIV and 75.8% agreed about routine HIV testing for all pregnant women. A higher level of knowledge was significantly associated with a favourable intended behaviour related to voluntary testing, disclosure and seeking professional assistance in the event of a positive HIV test. The results are discussed in relation to opt-in and opt-out approaches to voluntary testing during pregnancy.


Assuntos
Sorodiagnóstico da AIDS/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Gestantes/psicologia , Cuidado Pré-Natal/normas , Sorodiagnóstico da AIDS/normas , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Estudos Transversais , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Humanos , Entrevistas como Assunto , Pessoa de Meia-Idade , Omã , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Cuidado Pré-Natal/métodos , Adulto Jovem
12.
Immunol Lett ; 160(1): 58-64, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24747071

RESUMO

BACKGROUND: Toll-like receptors (TLRs) are essential elements of the innate immune response to different infections including HIV-1 infection. The single-nucleotide polymorphisms (SNPs) in TLRs have been associated with CD4T cell count and HIV disease progression. The TLR7 (Gln11Leu) SNP was shown to be associated with a rapid decline of CD4T cell count. A relation between TLR9 (1635A/G) SNP and CD4T cells count in HIV-infected patients is suggested, although the outcome associated with this SNP is still controversial. OBJECTIVES: To determine the relation of the TLR7 (Gln11Leu) and TLR9 (1635A/G) SNPs with the damage to the immune system during HIV infection as reflected by the average CD4T cell count. METHODS: A total of 63 HIV-infected patients and 100 healthy individuals (controls) were enrolled in this study. The above named SNPs were analyzed after amplification of the regions that potentially contain the SNPs by polymerase chain reaction (PCR) and sequencing of the PCR products. The frequency of these SNPs and their relation with the CD4T cell count were investigated. RESULTS: The TLR7 (AA) genotype 'Gln' had a trend toward being associated with a CD4T cell count >400cells/µl after controlling viremia via HAART. Additionally, the TLR9 1635 (GG) genotype was associated with a low average CD4T cell count and the TLR9 1635 (AG) genotype was significantly related to a higher average CD4T cell count during the viremic period in HIV-infected patients. CONCLUSION: The results of this longitudinal study supports the presence of an association between the TLR9 (1635A/G) genotype and the CD4T cell count, which helps clarifying the controversial results regarding this association. It also suggests that the CD4T cell count during the viremic period might be linked to the combination of both TLR7 (Gln11Leu) and TLR9 (1635A/G) genotypes. These results may help predicting the damage to the immune system, and thus impacting the planning for novel anti-HIV strategies.


Assuntos
Contagem de Linfócito CD4 , Infecções por HIV/genética , Infecções por HIV/imunologia , HIV-1/imunologia , Polimorfismo de Nucleotídeo Único , Receptor 7 Toll-Like/genética , Receptor Toll-Like 9/genética , Adulto , Alelos , Substituição de Aminoácidos , Terapia Antirretroviral de Alta Atividade , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Carga Viral
13.
Int J Immunogenet ; 41(1): 20-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23953748

RESUMO

C-C motif chemokine receptor-5 (CCR5) is a pro-inflammatory receptor that binds to chemokines and facilitates the entry of the R5 strain of HIV-1. A number of polymorphisms were identified within the promoter and coding regions of the CCR5 gene, some of which have been found to affect the protein expression and thus receptor function. Although several CCR5 polymorphisms were shown to vary widely in their distribution among different ethnic populations, there has been no study addressing the potential variants of the CCR5 gene in the Omani population. The aim of this study was to identify the polymorphic sites that exist within the CCR5 gene in Omanis. Blood samples were collected from 89 Omani adult individuals, and genomic DNA was amplified by polymerase chain reaction and sequenced to identify the polymorphic sites. The distribution of the detected variants was examined and compared with the previously published data. Four new indels were detected of 32 variable positions, -2973A/-, -2894A/-, -2827TA/- and -2769T/-, and all were located in the 5'UTR. Furthermore, two new mutations, -2248G/A and +658A/G, were observed for the first time; the -2248G/A was detected in the intron 1 region in one subject and +658A/G in the coding region of the CCR5 in another subject. In silico analysis showed that the novel variations in the 5'UTR may have effects on the transcription factor binding sites. Therefore, this study demonstrates the presence of two new SNPs and four novel indels in the CCR5 gene in the Omani population. Our findings support the wide spectrum of genetic diversity reported within the CCR5 gene region among different ethnic groups.


Assuntos
Polimorfismo Genético , Receptores CCR5/genética , Regiões 5' não Traduzidas , Adulto , Alelos , Sítios de Ligação , Biologia Computacional/métodos , Frequência do Gene , Predisposição Genética para Doença , Infecções por HIV/genética , Haplótipos , Humanos , Mutação INDEL , Desequilíbrio de Ligação , Mutação , Omã , Mapeamento Físico do Cromossomo , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Receptores CCR2/genética , Fatores de Transcrição/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-22666294

RESUMO

The objective of the study is to investigate the anti-snake venom activities of a local plant, Hibiscus aethiopicus L. The H. aethiopicus was dried and extracted with ethanol. Different assays were performed according to standard techniques, to evaluate the plant's acute toxicity and its antivenom activities. The results of evaluating the systemic acute toxicity of the H. aethiopicus extract using "oral and intra-peritoneal" route were normal even at the highest dose (24 g/kg) tested. All guinea pigs (n = 3) when treated with venoms E. c. sochureki (75 µg) alone induced acute skin haemorrhage. In contrast, all guinea pigs (n = 18) treated with both venom and the plant extract at a concentration between 500 and 1000 mg/kg showed no signs of haemorrhage. Moreover, all guinea pigs (n = 18) treated with venom and the plant extract below 400 mg/kg showed acute skin haemorrhage. All guinea pigs treated with venom E. c. sochureki (75 µg) alone induced acute skin haemorrhage after both 24 and 32 hours. In contrast, all guinea pigs treated with both venom and the plant extract (administered independently) at concentrations between 500 and 1000 mg/kg showed no signs of haemorrhage after 32 hours. However, after 24 hours all tested guinea pigs showed less inhibition (<60%) compared to that obtained after 32 hours. The outcome of this study reflects that the extract of H. aethiopicus plant may contain an endogenous inhibitor of venom induced local haemorrhage.

15.
Rev Med Suisse ; 8(323): 23-7, 2012 Jan 11.
Artigo em Francês | MEDLINE | ID: mdl-22303735
16.
Plant Dis ; 96(6): 852-858, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30727347

RESUMO

A study was conducted to investigate phenotypic and genotypic changes within Pythium aphanidermatum populations during the period 2006 to 2011. In total, 92 isolates of P. aphanidermatum (59 in 2006 and 33 in 2011) were obtained from different planting sites (soil) of cucumber from a single greenhouse. Generated sequences of the internal transcribed spacer (ITS) ribosomal DNA showed that all, except one isolate, share an identical sequence of the ITS region. Most (89%) P. aphanidermatum isolates were found to be aggressive on cucumber seedlings, with no significant differences in the aggressiveness level between populations obtained from different planting rows or different years. Sensitivity to metalaxyl among populations of P. aphanidermatum increased significantly from concentration resulting in 50% growth inhibition levels of 0.070 to 1.823 (average 0.824 µg ml-1) in 2006 to 0.002 to 0.564 (average 0.160 µg ml-1) in 2011. Amplified fragment length polymorphism analysis of the 92 isolates produced 92 different genotypes and 985 polymorphic loci. P. aphanidermatum populations from 2006 and 2011 were found to have low levels of genetic diversity (H = 0.1425), which implies introduction of the isolates into the greenhouse via common sources. Results from analysis of molecular variance (FST = 0.0307 in 2006 and 0.0222 in 2011) provided evidence for frequent exchange of Pythium inoculum between different planting locations within the same year. However, the analysis showed moderate levels (FST = 0.1731) of genetic differentiation among populations from the 2 years. This was supported by unweighted pair group method with arithmetic means analysis, which showed clustering of many of the 2006 isolates in separate clusters. The change in the metalaxyl sensitivity of the populations from 2006 to 2011 accompanied by the genetic differences among these two populations may suggest that many of the isolates from 2006 were lost and were replaced by new and highly sensitive P. aphanidermatum isolates by 2011.

17.
Rev Med Suisse ; 7(277): 30-2, 34-5, 2011 Jan 12.
Artigo em Francês | MEDLINE | ID: mdl-21309171

RESUMO

In 2010, a study emphasizes the difficulty to predict disability trajectories in the last year of life. A meta analysis shows the effectiveness of post-acute geriatric rehabilitation in reducing functional decline after hospitalisation. Several studies evaluated pneumococcal and herpes zoster vaccines' efficacy. A short and simple intervention is effective in reducing benzodiazepine use. The effect of vitamine D on falls and fractures has been further evaluated in several studies. Diagnostic criteria for dementias, including Alzheimer's disease, are moving to better acknowledge their preclinical stages.


Assuntos
Geriatria/tendências , Idoso , Humanos
18.
Asian Pac J Trop Biomed ; 1(3): 173-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23569753

RESUMO

OBJECTIVE: To investigate the antibacterial activity of henna (Lawsonia inermis Linn) obtained from different regions of Oman against a wide array of micro-organisms. METHODS: Fresh henna samples were obtained from different regions of Oman as leaves and seeds. 100 g fresh and dry leaves and 50 g of fresh and dry seeds were separately soaked in 500 mL of ethanol for three days, respectively, with frequent agitation. The mixture was filtered, and the crude extract was collected. The crude extract was then heated, at 48 °C in a water bath to evaporate its liquid content. The dry crude henna extract was then tested for its antibacterial activity using well-diffusion antibiotic susceptibility technique. Henna extracts were investigated for their antibacterial activity at different concentrations against a wide array of different micro-organisms including a laboratory standard bacterial strain of Pseudomonas aeruginosa (NCTC 10662) (P. aeruginosa) and eleven fresh clinical isolates of P. aeruginosa obtained from patients attending the Sultan Qaboos University Hospital (SQUH). 2-Hydroxy-p-Nathoqinone-Tech (2-HPNT, MW=174.16, C10H6O3) was included as control (at 50% concentration) along with the henna samples tested. RESULTS: Henna samples demonstrated antibacterial activity against all isolates but the highest susceptibility was against P. aeruginosa with henna samples obtained from Al-sharqyia region. CONCLUSIONS: Omani henna from Al-sharqyia region demonstrates high in vitro anti-P. aeruginosa activity compared with many henna samples from different regions of Oman.


Assuntos
Antibacterianos/farmacologia , Lawsonia (Planta)/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Componentes Aéreos da Planta/química
19.
Artigo em Inglês | MEDLINE | ID: mdl-20936075

RESUMO

Envenoming by Echis saw-scaled viper is the leading cause of death and morbidity in Africa due to snake bite. Despite its medical importance, there have been few investigations into the toxin composition of the venom of this viper. Here, we report the cloning of cDNA sequences encoding four groups or isoforms of the haemostasis-disruptive Serine protease proteins (SPs) from the venom glands of Echis ocellatus. All these SP sequences encoded the cysteine residues scaffold that form the 6-disulphide bonds responsible for the characteristic tertiary structure of venom serine proteases. All the Echis ocellatus EoSP groups showed varying degrees of sequence similarity to published viper venom SPs. However, these groups also showed marked intercluster sequence conservation across them which were significantly different from that of previously published viper SPs. Because viper venom SPs exhibit a high degree of sequence similarity and yet exert profoundly different effects on the mammalian haemostatic system, no attempt was made to assign functionality to the new Echis ocellatus EoSPs on the basis of sequence alone. The extraordinary level of interspecific and intergeneric sequence conservation exhibited by the Echis ocellatus EoSPs and analogous serine proteases from other viper species leads us to speculate that antibodies to representative molecules should neutralise (that we will exploit, by epidermal DNA immunization) the biological function of this important group of venom toxins in vipers that are distributed throughout Africa, the Middle East, and the Indian subcontinent.


Assuntos
Análise de Sequência de DNA/métodos , Serina Proteases , Venenos de Víboras , Viperidae , Sequência de Aminoácidos , Animais , Antígenos , Sequência de Bases , DNA Complementar/química , Bases de Dados Genéticas , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Serina Proteases/química , Serina Proteases/genética , Especificidade da Espécie , Venenos de Víboras/química , Venenos de Víboras/genética
20.
J Toxicol ; 2010: 837864, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20628507

RESUMO

The objective of the study is to investigate whether the Hibiscus aethiopicus L. plant has neutralization activity against venoms of two clinically important snakes. The H. aethiopicus was dried and extracted with water. Different assays were performed to evaluate the plant's acute toxicity and its anti-snake venom activities. The results showed that H. aethiopicus extract alone had no effect on the viability of C(2)C(12) muscle cells, but significantly (P < .05) protected muscle cells against the toxic effects of E. ocellatus venom at 55, 150, and 300 mug/mL. The maximum protective effect of the extract was exhibited at 75 mug/mL. The extract significantly (P < .001) inhibited the cytotoxic effects of E. ocellatus venom at 300 mug/mL. All rabbits (n = 10) and guinea pigs (n = 10) were alive after the two weeks of given the lethal dosage 16 g/Kg of the H. aethiopicus extract herbal solution. No abnormal behaviour was observed of both groups of animals. All guinea pigs (n = 3) treated with venoms alone (5 mg/kg) died. However, all guinea pigs (n = 21) treated with venom (5 mg/kg) and the extract (400 to 1000 mg/kg) survived. Guinea pigs (n = 3) treated with Naja n. nigricollis venom alone (2.5 mg/kg) and guinea pigs (n = 21) venom with the extract (400 to 1000 mg/kg) died. The H. aethiopicus completely (100%) blocked the haemorrhagic activity of E. ocellatus in the egg embryo at 3.3 mg/mL of extract. These findings suggest that H. aethiopicus may contain an endogenous inhibitor of venom-induced haemorrhage.

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