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1.
Cureus ; 15(11): e48881, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38106789

RESUMO

Background This study aimed to analyze the health and demographic characteristics of blood donors in Makkah, Saudi Arabia, and assess the prevalence and correlation of two markers related to hepatitis B infection: hepatitis B virus surface antigen (HBsAg) and anti-hepatitis B virus surface antibody (HBsAb). Materials and methods The study used a retrospective design and collected data from the Central Blood Bank in Makkah, Saudi Arabia, in 2022. The sample size was 7,875 blood donors. The study used various methods, such as serological testing, nucleic acid testing (NAT), and statistical analysis. The data were analyzed using Pearson correlation to examine the relationships between different variables. Results The predominant age group was 29-39 years, accounting for 46.9% of the total donors. In terms of blood types, O+ve was the most common, representing 40.3% of the donors. The investigation into infectious markers revealed overall low levels of reactivity among donors. For HBsAg, a marker of active hepatitis B infection, only 0.36% of the units were reactive. Conversely, the anti-HBsAb, which indicates immunity to hepatitis B, was reactive in 6.83% of the units. The correlation analysis illuminated some critical relationships. The total number of units tested had a statistically significant, albeit weak, positive relationship with HBsAg reactivity, shown by a Pearson correlation coefficient of 0.030 and a p-value of 0.008. Conversely, the total number of units tested and anti-HBsAb reactivity showed a moderate negative correlation, with a Pearson correlation coefficient of -0.437 and a p-value of less than 0.001. However, no significant correlation was identified between HBsAg and anti-HBsAb reactivity, indicating that active infection and immunity status might not be directly linked. Conclusion This extensive study provides in-depth insights into the sociodemographic characteristics of blood donors and the prevalence of key infectious markers within this population. It underlines the imperative of rigorous screening of blood units, particularly given the low immunity levels to hepatitis B identified. Also, the study showed the importance of screening blood units and vaccinating people against hepatitis B. It also suggested the need for more research on blood safety and infection-immunity relationships.

2.
Pathogens ; 12(9)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37764883

RESUMO

Bloodstream infection (BSI) prevalence in hospitalized patients has increased owing to the spread of antibiotic-resistant pathogens; moreover, antimicrobial resistance in bacteria is a global problem. Here, BSIs are investigated in several patients at a hospital in Saudi Arabia, and the resistance of bacterial isolates to widely used drugs is determined. Throughout 2020, bacteria isolated from patients were identified and subjected to antibiotic susceptibility testing. In total, 1125 bacterial isolates were obtained from 1039 patients; among them, gram-positive bacteria were significantly more abundant than gram-negative bacteria. The most prevalent bacteria were Staphylococcus epidermidis and Klebsiella pneumoniae. Notably, gram-negative bacteria were mainly isolated from adult patients, and 20.63% of the gram-positive isolates were from pediatric patients, which was significantly higher than the corresponding percentages in elders and adults. The gram-positive isolates were mainly resistant to cephalothin, oxacillin, amoxicillin-clavulanate, and erythromycin and susceptible to penicillin, gentamicin, ciprofloxacin, and vancomycin. Additionally, the gram-negative isolates were mainly resistant to ampicillin, cephalothin, and amoxicillin-clavulanate and susceptible to amikacin, ertapenem, aztreonam, colistin, and trimethoprim-sulfamethoxazole. Consequently, the high prevalence of infective multidrug-resistant bacteria may account as a significant health issue; it is considered a hazard in Riyadh hospitals and must be prevented at all costs.

3.
J Infect Public Health ; 16(1): 25-33, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36459708

RESUMO

PURPOSE: To investigate the dematiaceous fungal profile of patients with ocular mycoses attending a tertiary eye care hospital in Coimbatore, India METHODS: The identification of dematiaceous fungus based on their morphology, their genotypes, and the measurement of the minimum inhibitory concentrations (MICs) using microdilution method of routinely used antifungal drugs were all compared. RESULTS: A total of 148 dematiaceous fungi were isolated during a study period of 27 months. Isolates were confirmed as Curvularia spp. (n = 98), Exserohilum spp. (n = 32), Alternaria spp. (n = 14), Exophiala spp. (n = 2), Cladosporium sp. (n = 1) and Aureobasidium sp. (n = 1). Out of 50 well grown isolates characterized genotypically based on the amplification and sequencing of the ITS region of the ribosomal RNA gene cluster and subsequent BLAST analysis, Curvularia lunata (n = 24), C. aeria (n = 1), C. spicifera (n = 8), C. hawaiiensis (n = 1), C. maydis (n = 2), C. papendorfii (n = 2), C. geniculata (n = 3), C. tetramera (n = 2) and Exs. rostratum (n = 7) were identified. In vitro antifungal susceptibilities of the most tested dematiaceous isolates showed that voriconazole had a MIC50 of 0.25 µg ml-1, while amphotericin B had a MIC50 of 0.25 µg ml-1 for Curvularia spp. and Alternaria spp. CONCLUSION: Voriconazole proved to be the most effective drug against the pigmented filamentous fungi, followed by amphotericin B, itraconazole and econazole.


Assuntos
Antifúngicos , Infecções Oculares Fúngicas , Humanos , Antifúngicos/farmacologia , Anfotericina B/farmacologia , Voriconazol/farmacologia , Voriconazol/uso terapêutico , Filogenia , Infecções Oculares Fúngicas/microbiologia , Fungos , Testes de Sensibilidade Microbiana
4.
J Infect Public Health ; 15(4): 379-388, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35299061

RESUMO

BACKGROUND: An ischemic stroke can be caused by thrombosis and ischemia, which is a major public health problem around the world, resulting in severe disability and a high death rate. The goal of this work is to examine and target various heat shock proteins (HSPs) via their interacting partners, which may have an anti-ischemic stroke impact. METHODS: Various heat shock proteins are identified and used for construction of PPI network through STRING webserver. Networks are analysed and visualized using the cytoscape for checking the protein-protein interactions. Along with this, multiple cytoscape based modules are integrated for the analysis of results, and Gene Ontology results are analysed using GOView. RESULTS: The core PPI network was revealed with 129 nodes and 1174 edges. Through Gene ontology (GO) and KEGG enrichment analysis the promising function of HSPs in two important signaling pathways were mainly recorded, representing the HSPs are necessary for repair and activations of brain cells during ischemic stroke. In addition, the study is revelation for targeting multiple HSPs via their interacting partners, which can provide anti-ischemic stroke effect. CONCLUSION: Overall, this finding provides a network-based framework for future research on HSP as therapeutic molecules for anti-ischemic stroke related applications.


Assuntos
Proteínas de Choque Térmico , AVC Isquêmico , Encéfalo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Transdução de Sinais/genética
5.
J King Saud Univ Sci ; 34(4): 101924, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35233153

RESUMO

The function of Immune control, haematopoiesis, and inflammation all depend on the cytokine Interleukin 6 (IL-6), and higher expression of IL-6 is seen in COVID-19 and other diseases. The immune protein IL-6 activation is dependent on binding interactions with IL-6Rα, mIL-6R, and sIL-6R for its cellular function. Termination of these reaction could benefit for controlling the over-expression in COVID-19 patients and that may arise as inhibitors for controlling COVID-19. Traditionally, the goat milk has been prescribed as medicine in ayurvedic practice and through this work, we have explored the benefits of peptides from goat milk as IL-6 inhibitors, and it have the potential of inhibiting the over expression of IL-6 and control the COVID-19 disease. Computational experiments have shown that goat peptides had strong interactions with IL-6, with higher scoring profiles and energy efficiency ranging from -6.00 kcal/mol to -9.00 kcal/mol in docking score and -39.00 kcal/mol in binding energy. Especially the YLGYLEQLLR, VLVLDTDYK and AMKPWIQPK peptides from goat milk holds better scoring and shows strong interactions were identified as the most potential IL-6 inhibitor candidates in this study. Peptides from Goat proteins, which are capable of binding to the IL-6 receptor with strong binding conformations, have no negative effects on other immune system proteins.

6.
Saudi J Biol Sci ; 29(2): 984-991, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35197767

RESUMO

Nitric oxide (NO) is one of the major signalling molecules in the mammalian body playing critical role in regulation of blood pressure, cardiovascular disease including stroke, immune activation, neuronal and cell communication. Moreover, hyper production of NO by the activity of nitric oxide synthase (NOS) involved in neuropathic pain, neurodegenerative disorders and stroke. Hence, the search on small molecules from the natural sources for the inhibition of NOS is desirable in therapeutic point of view. The elevated level of NO caused by NOS enzyme become a novel target in finding new inhibitors from natural sources as antistroke agents. The present study focuses on the molecular docking of quercetin and its analogues against NOS. The active site of the enzyme was docked with the ligand and pharmacological properties were analysed. From this result, we suggest the therapeutic property of quercetin and its analogues against NOS.

7.
J Fungi (Basel) ; 7(8)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34436171

RESUMO

The present study was carried out to analyze the potential of fungi isolated from the rhizosphere of soybean, brinjal, tomato, and potato plants. The density of fungi varied in the pot soil and rhizosphere after Paecilomyces formosus MD12 treatment. The P. formosus MD12 population was 6.3 ± 0.13 × 104 CFU g-1 in the pot planted with brinjal, and the population increased in the rhizosphere (6.72 ± 0.41 × 104 CFU g-1). P. formosus MD12 was cultured in the production medium, and the supernatant was used for egg inhibition studies on a root-knot nematode parasite, Meloidogyne incognita. It was revealed that maximum egg inhibition (94.7 ± 6.2%) was obtained at 100% concentration of extract. The culture supernatant from P. formosus MD12 affected the development of M. incognita juvenile, and the mortality rate was maximum after 96 h (95 ± 6%). Mortality was reduced when treated with 25%, 50%, and 75% supernatant. At 1 × 107 mL-1 of spore suspension, we found reductions of 71.6 ± 3.3% nematode populations in the soil, 60.7 ± 2.2% from the root, and 63.6 ± 2.4% egg mass compared with the control in the pot experiment. The culture supernatant applied at the 10% level showed a maximum mean reduction of the nematode population in roots (72.4 ± 2.2%), soil (77.9 ± 2.5%), and egg masses (73.2 ± 1.5%), respectively. The presence of P. formosus MD12 in a soil environment could antagonize nematode parasites and improve soil amendment. The P. formosus MD12 strain showed good biocontrol ability against the root-knot nematode, M. incognita, under in vitro and green house experimental condition.

8.
J Fungi (Basel) ; 7(5)2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33923354

RESUMO

Microbial natural biocides have attracted much more attention in recent years in order to avoid the unrestricted use of chemical biocides in the environment. The aim of this study is to analyze the antibacterial and antifungal activities of secondary metabolites and growth promoting, nematicidal, and soil enzyme activity mediated by Trichoderma hamatum FB10. The bactericidal and fungicidal activities were performed using cell-free extract. Results revealed that the selected strain exert antibacterial activity against Acidovorax avenae, Erutimacarafavora, and Xanthomonas campestris. The selected fungal strain FB10 showed antagonistic activity against fungal pathogens such as, S. sclerotiorum, Rhizoctonia solani, Alternaria radicina, Alternaria citri, and Alternaria dauci. Among the bacterial pathogens, A. avenae showed least MIC (30 ± 2.5 µg/mL) and MBC (70 ± 1.25 µg/mL) values. T. hamatum FB10 strain synthesized bioactive volatile secondary metabolite, which effectively inhibited the growth of bacteria and fungi and indicated the presence of 6-pentyl-alpha-pyrone as the major compound (67.05%). The secondary metabolite synthesized by T. hamatum FB10 showed nematicidal activity against M. incognita eggs. Egg hatch inhibition was 78 ± 2.6% and juvenile stage mortality rate was 89 ± 2.5% when the strain FB10 was treated with nematode. The cell free extract of T. hamatum FB10 showed protease, amylase, cellulase, chitinase, glucanase activities. T. hamatum FB10 inoculated with green gram increased 11% plant height, compared to the control. The fresh weight of the experimental group inoculated with T. hamatum FB10 increased 33.6% more compared to the control group. The green gram seedlings inoculated with T. hamatum FB10 increased 18% more dry weight than control group. Soil enzymes such as, urease, phosphatase, catalase and saccharase were improved in the soil inoculated with T. hamatum FB10. These biochemical components play potent role in soil fertility, energy conversion, and in soil organic matter conversion.

9.
J Infect Public Health ; 13(12): 1907-1911, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33162353

RESUMO

BACKGROUND AND OBJECTIVES: Aspergillus keratitis are in the increasing trend and reported as the second most common cause of mycotic keratitis in developing countries. The present study was designed to isolate, identify Aspergillus spp. from the keratits/corneal ulcer patients attending a tertiary care eye hospital, Coimbatore, South India and to assess the minimum inhibitory concentrations (MICs) against ten clinically used first-line antifungal drugs. METHODS: A total of seventy-three Aspergillus strains isolated from corneal scrapings were included and assessed for a period of one year. All isolates were identified up to the species level by morphological observations. Antifungal drug susceptibilities were determined against a standard panel of antifungal agents. CONCLUSIONS: Five different species of aspergilli, A. flavus (n=53), A. fumigatus (n=14), A. terreus (n=9), A. tamarii (n=6) and A. niger (n=3) were identified based on morphological features. Minimum inhibitory concentration analyses indicated that, voriconazole, natamycin, itraconazole, clotrimazole, econazole followed by ketoconazole shall be the order of choices for the effective treatment for Aspergillus keratitis.


Assuntos
Úlcera da Córnea , Preparações Farmacêuticas , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergillus , Úlcera da Córnea/tratamento farmacológico , Humanos , Índia , Testes de Sensibilidade Microbiana , Níger
10.
Saudi J Biol Sci ; 27(2): 701-705, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32210691

RESUMO

Mycotic/fungal keratitis is a suppurative, generally ulcerative infection of the cornea. The filamentous fungi, Aspergillus spp. are the second leading cause of mycotic keratitis, particularly in India. Aspergillus spp. produce a range of extracellular enzymes that are used to break down complex molecules and used for growth and reproduction, also for survival on/in host organism. The current study was designed with an objective to screen in vitro extracellular enzyme activity of Fusarium and Aspergillus isolates from mycotic keratitis patients and to correlate the same as a putative virulence factor. Extracellular enzymes viz., deoxyribonuclease (DNase), protease, lipase, elastase, keratinase, etc., produced by Aspergillus have key role in keratomycosis and hence their (n = 85) in vitro activities were investigated. It was found that, the majority of the Aspergillus isolates produced protease (n = 75; 88% of 85) followed by lipase (n = 59; 69% of 85), DNase (n = 35; 41% of 85), elastase (n = 26; 31% of 85) and keratinase (n = 13; 15% of 85). The enzyme activity indices (EAI) for DNase, elastase, protease and lipase ranged between 1.01 and 1.98, whereas elastase EAI varied between 1.26 and 1.92. DNase, protease and lipase showed a maximum EAI of 1.98 and lowest EAI value of 1.01, respectively. Extracellular enzymes of Aspergillus spp. may have potential role in the onset and progression of keratitis.

11.
FEMS Microbiol Lett ; 366(21)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816013

RESUMO

Trichoderma species are abundant in different agricultural habitats, but some representatives of this genus, mainly clade Longibrachiatum members are also emerging as causative agents of various human diseases with even fatal outcome. Strains of these species frequently show resistance to commonly used azole antifungals. Based on previous data it is hypothesized that Trichoderma isolates identified in human infections derive from environmental-including agricultural-origins. We examined Trichoderma longibrachiatum Rifai and Trichoderma bissettii Sandoval-Denis & Guarro strains recovered from four novel cases of human mycoses, along with isolates from previous case reports and different agricultural habitats, using multilocus phylogenetic analysis, BIOLOG Phenotype Microarrays and Etest. Strains attributed to T. bissettii were more abundant in both clinical and agricultural specimens compared to T. longibrachiatum. The majority of the isolates of both taxa could tolerate >256, >32 and >32 µg/ml fluconazole, itraconazole and posaconazole, respectively. None of the obtained results revealed characteristic differences between strains of clinical and agricultural origin, nor between the two taxa, supporting that agricultural environments may be significant sources of infections caused by these emerging human fungal pathogens. Furthermore, based on our findings we propose the re-classification of T. bissettii as T. longibrachiatum f. sp. bissettii.


Assuntos
Agricultura , Exposição Ambiental , Microbiologia Ambiental , Micoses/microbiologia , Trichoderma/isolamento & purificação , Antifúngicos/farmacologia , Fluconazol/farmacologia , Humanos , Itraconazol/farmacologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Técnicas de Tipagem Micológica , Micoses/epidemiologia , Filogenia , Triazóis/farmacologia , Trichoderma/classificação , Trichoderma/efeitos dos fármacos , Trichoderma/genética
12.
Pathogens ; 9(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861831

RESUMO

Members of the genus Curvularia are melanin-producing dematiaceous fungi of increasing clinical importance as causal agents of both local and invasive infections. This study contributes to the taxonomical and clinical knowledge of this genus by describing two new Curvularia species based on isolates from corneal scrapings of South Indian fungal keratitis patients. The phylogeny of the genus was updated based on three phylogenetic markers: the internal transcribed spacer (ITS) region of the ribosomal RNA gene cluster as well as fragments of the glyceraldehyde-3-phosphate dehydrogenase (gpdh) and translation elongation factor 1-α (tef1α) genes. The maximum likelihood phylogenetic tree constructed from the alignment of the three concatenated loci revealed that the examined isolates are representing two new, yet undescribed, Curvularia species. Examination of colony and microscopic morphology revealed differences between the two species as well as between the new species and their close relatives. The new species were formally described as Curvularia tamilnaduensis N. Kiss & S. Kocsubé sp. nov. and Curvularia coimbatorensis N. Kiss & S. Kocsubé sp. nov. Antifungal susceptibility testing by the broth microdilution method of CLSI (Clinical & Laboratory Standards Institute) revealed that the type strain of C. coimbatorensis is less susceptible to a series of antifungals than the C. tamilnaduensis strains.

13.
Front Microbiol ; 10: 2249, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31649626

RESUMO

Aspergillus tamarii appears to be an emerging aetiological agent of human keratomycoses in South India. The investigated strains were isolated from six suspected fungal keratitis patients attending a tertiary care eye hospital in Coimbatore (Tamil Nadu, India), and were initially identified by the microscopic examinations of the scrapings and the cultures. Our data suggest that A. tamarii could be easily overlooked when identification is carried out based on morphological characteristics alone, while the sequence analysis of the calmodulin gene can be used successfully to recognize this species accurately. According to the collected clinical data, ocular trauma is a common risk factor for the infection that gradually developed from mild to severe ulcers and could be healed with an appropriate combined antifungal therapy. Antifungal susceptibility testing revealed that A. tamarii strains are susceptible to the most commonly used topical or systemic antifungal agents (i.e., econazole, itraconazole and ketoconazole) except for natamycin. Moreover, natamycin proved to be similarly less effective than the azoles against A. tamarii in our drug interaction tests, as the predominance of indifferent interactions was revealed between natamycin and econazole and between natamycin and itraconazole as well. Four and five isolates of A. tamarii were confirmed to produce cyclopiazonic acid (CPA) in RPMI-1640 - which is designed to mimic the composition of human extracellular fluids - and in yeast extract sucrose (YES) medium, respectively, which is a widely used culture medium for testing mycotoxin production. Although a ten times lower mycelial biomass was recorded in RPMI-1640 than in YES medium, the toxin contents of the samples were of the same order of magnitude in both types of media. There might be a relationship between the outcome of infections and the toxigenic properties of the infecting fungal strains. However, this remains to be investigated in the future.

14.
Biomed Res Int ; 2019: 6395840, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30800674

RESUMO

Fungal aetiology of keratitis/corneal ulcer is considered to be one of the leading causes of ocular morbidity, particularly in developing countries including India. More importantly, Fusarium and Aspergillus are reported commonly implicating corneal ulcer and against this background the present work was undertaken so as to understand the current epidemiological trend of the two fungal keratitis. During the project period, a total of 500 corneal scrapings were collected from suspected mycotic keratitis patients, of which 411 (82.2%) were culture positive for bacteria, fungi, and parasites. Among fungal aetiologies, Fusarium (216, 52.5% of 411) and Aspergillus (68, 16.5% of 411) were predominantly determined. While the study revealed a male preponderance with both the fungal keratitis , it further brought out that polyene compounds (natamycin and amphotericin B) and azoles were active, respectively, against Fusarium spp. and Aspergillus spp. Additionally, 94.1% of culture proven Fusarium keratitis and, respectively, 100% and 63.6% of A. flavus and A. fumigatus were confirmed by multiplex PCR. The sensitivity of the PCR employed in the present study was noted to be 10 fg/µl, 1 pg/µl, and 300 pg/µl of DNA, respectively, for Fusarium, A. flavus, and A. fumigatus. Alarming fact was that Fusarium and Aspergillus regionally remained to be the common cause of mycotic keratitis and the Fusarium isolates had a higher antifungal resistance than Aspergillus strains against most of the test drugs.


Assuntos
Antifúngicos/uso terapêutico , Aspergillus/efeitos dos fármacos , Úlcera da Córnea/tratamento farmacológico , Infecções Oculares Fúngicas/tratamento farmacológico , Fusarium/efeitos dos fármacos , Ceratite/tratamento farmacológico , Ceratite/epidemiologia , Adulto , Idoso , Anfotericina B/uso terapêutico , Aspergilose/tratamento farmacológico , Azóis/uso terapêutico , Córnea/microbiologia , Úlcera da Córnea/microbiologia , Farmacorresistência Fúngica/efeitos dos fármacos , Infecções Oculares Fúngicas/microbiologia , Feminino , Fusariose/tratamento farmacológico , Fusariose/microbiologia , Humanos , Índia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Natamicina/uso terapêutico , Adulto Jovem
15.
Front Microbiol ; 9: 1052, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29875757

RESUMO

Members of the Fusarium solani species complex (FSSC) are the most frequently isolated fusaria from soil. Moreover, this complex solely affects more than 100 plant genera, and is also one of the major opportunistic human pathogenic filamentous fungi, being responsible for approximately two-third of fusariosis cases. Mycotic keratitis due to Fusarium species is among the leading causes of visual impairment and blindness in South India, but its management is still challenging due to the poor susceptibility of the isolates to conventional antifungal drugs. Aims of the present study were to isolate South Indian clinical and environmental FSSC strains and identify them to species level, to determine the actual trends in their susceptibilities to antifungal therapeutic drugs and to compare the virulence of clinical and environmental FSSC members. Based on the partial sequences of the translation elongation factor 1α gene, the majority of the isolates-both from keratomycosis and environment-were confirmed as F. falciforme, followed by F. keratoplasticum and F. solani sensu stricto. In vitro antifungal susceptibilities to commonly used azole, allylamine and polyene antifungals were determined by the CLSI M38-A2 broth microdilution method. The first generation triazoles, fluconazole and itraconazole proved to be ineffective against all isolates tested. This phenomenon has already been described before, as fusaria are intrinsically resistant to them. However, our results indicated that despite the intensive agricultural use of azole compounds, fusaria have not developed resistance against the imidazole class of antifungals. In order to compare the virulence of different FSSC species from clinical and environmental sources, a Drosophila melanogaster model was used. MyD88 mutant flies having impaired immune responses were highly susceptible to all the examined fusaria. In wild-type flies, one F. falciforme and two F. keratoplasticum strains also reduced the survival significantly. Pathogenicity seemed to be independent from the origin of the isolates.

16.
Exp Eye Res ; 174: 1-12, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29772229

RESUMO

The conjunctival sac of healthy human harbours a variety of microorganisms. When the eye is compromised, an occasional inadvertent spread happens to the adjacent tissue, resulting in bacterial ocular infections. Microbiological investigation of the conjunctival swab is one of the broadly used modality to study the aetiological agent of conjunctiva. However, most of the time such methods yield unsatisfactory results. Hence, the present study intends to identify the bacterial community in human conjunctiva of pre-operative subjects through 16S rRNA gene libraries. Out of 45 samples collected from preoperative patients undergoing cataract surgery, 36 libraries were constructed with bacterial nested-PCR-positive samples. The representative clones with unique restriction pattern were generated through Amplified Ribosomal DNA Restriction Analysis (ARDRA) which were sequenced for phylogenetic affiliation. A total of 211 representative clones were obtained which were distributed in phyla Actinobacteria, Firmicutes, α-Proteobacteria, ß-Proteobacteria, γ-Proteobacteria, Bacteroidetes, and Deinococcus-Thermus. Findings revealed the presence of polybacterial community, especially in some cases even though no bacterium or a single bacterium alone was identified through cultivable method. Remarkably, we identified 17 species which have never been reported in any ocular infections. The sequencing data reported 6 unidentified bacteria suggesting the possibility of novel organisms in the sample. Since, polybacterial community has been identified consisting of both gram positive and gram negative bacteria, a broad spectrum antibiotic therapy is advisable to the patients who are undergoing cataract surgery. Consolidated effort would significantly improve a clear understanding of the nature of microbial community in the human conjunctiva which will promote administration of appropriate antibiotic regimen and also help in the development of oligonucleotide probes to screen the predominant pathogens for early predisposition.


Assuntos
Técnicas Bacteriológicas/métodos , Túnica Conjuntiva/microbiologia , Infecções Oculares Bacterianas/diagnóstico , Biblioteca Gênica , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos , Bactérias/genética , DNA Bacteriano/genética , Humanos , Filogenia , Reação em Cadeia da Polimerase
17.
Mycopathologia ; 183(3): 603-609, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29374798

RESUMO

We report a case of a 59-year-old male patient with a postoperative fungal infection of the left eye. A dark-pigmented yeast, Exophiala dermatitidis (previously known as Wangiella dermatitidis), was identified from the culture of the biopsy taken from the posterior capsule. The infection was successfully eradicated by a combination of surgical and medical (i.e., voriconazole and fluconazole) treatment. This is the first report of successfully treated E. dermatitidis endophthalmitis, which demonstrates that a prompt and aggressive antifungal therapy combined with surgical intervention is necessary to prevent vision loss in cases of endophthalmitis due to Exophiala species. Beside the case description, we also aim to provide a literature review of previously reported eye infections caused by Exophiala species in order to help the future diagnosis and management of the disease.


Assuntos
Endoftalmite/diagnóstico , Endoftalmite/patologia , Exophiala/isolamento & purificação , Feoifomicose/diagnóstico , Feoifomicose/patologia , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/patologia , Antifúngicos/administração & dosagem , Biópsia , Desbridamento , Endoftalmite/microbiologia , Endoftalmite/terapia , Humanos , Masculino , Técnicas Microbiológicas , Pessoa de Meia-Idade , Feoifomicose/microbiologia , Feoifomicose/terapia , Pigmentos Biológicos/análise , Infecção da Ferida Cirúrgica/microbiologia , Infecção da Ferida Cirúrgica/terapia , Resultado do Tratamento
18.
ACS Omega ; 3(12): 17520-17527, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31458356

RESUMO

Remediation process produces high-value functional material from low-cost or valueless waste feedstock. Current research demonstrates an innovative solvothermal approach to effectively react sulfuric acid on polyethylene (PE) chains, modifying the PE at a moderate temperature. In this process, the polymer undergoes a cross-linking step above 120 °C, whereas above 500 °C, it transforms into turbostratic carbon structures. Scanning electron micrographs confirmed the free-standing carbon sheet architecture. Raman spectroscopy and X-ray diffraction verified the amorphous/disordered sp2/sp3 hybrid carbon structure in the produced carbons. A high Brunauer-Emmett-Teller surface area of 752.3 and 673.5 m2/g for low-density PE-derived carbon (LDPE-C) and high-density PE-derived carbon (HDPE-C), respectively, was recorded. Thermogravimetric analysis analysis established a total mass retention of 50 and 46% for LDPE and HDPE, respectively, from sulfonated materials. Li-ion battery composite anode comprising LDPE-C and HDPE-C, with a binder and a carbon additive (vs lithium), produced 230 and 350 mA h/g specific capacities for LDPE-C and HDPE-C, respectively, when cycled at room temperature at C/5 rate. Elevated temperature (50 °C) battery cycling produced 290 and 440 mA h/g specific capacities for LDPE-C and HDPE-C, respectively, at C/5 rate. On the basis of the literature survey, this is the first report, which demonstrates that a solvothermal sulfonation process followed by thermal treatment successfully converts waste LDPE and HDPE plastic bags to functional energy-storing carbons.

19.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-732391

RESUMO

@#Aims: To isolate and characterise actinomycetes from various sources of soil samples (fruit orchard, dipterocarp forest and oil palm plantation) and to screen these isolates forantibacterial activity against multi-drug resistant bacteria.Methodology and results: A total of 158 fast-growing actinomycete isolates with different colony morphologywere subjected to primary cross-streak and secondary well diffusion screening. Six isolates (OP1E, OP7A, OP2A-C, MG1A, UT9C1 and UT7E)were found to inhibit atleast one of the seven multi-drug resistant (MDR) bacteria. MG1A exhibited the strongest and broadest spectrum of antibacterial activity against 6 MDR bacteria tested. These isolates were identified as Streptomyces species based on 16S rRNA gene sequence analysis. Further morphological and biochemical analysis revealed that MG1A was highly similar to S. griseocarneus (98.36%)whereas OP1E and OP2A-C were similar to S. parvulus(99.93% and 99.51% respectively). Preliminary identification using LCMS/MS and database search revealed that the major compound in the extract of OP2A-C could be dactinomycin (1255.4170 g/mol). Other antibacterial compounds in the extracts remain to be identified. Conclusion, significance and impact of study: Soil actinomycetes with antibacterial activity against MDR bacteria were isolated not only from undisturbed natural soils but cultivated soils. These isolates were characterised, identified and the antibacterial compounds were extracted for further study. The isolates could serveas a potential source for the development of new and sustainable compounds against MDR bacteria.

20.
J Basic Microbiol ; 57(11): 899-909, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28902962

RESUMO

Aspergillus flavus is a filamentous fungus which is widespread on agricultural products and also able to cause various human diseases. This species is frequently isolated from indoor air as well, furthermore, it is known as a common causal agent of keratomycosis, particularly in subtropical and tropical areas. It is also able to produce aflatoxins, one of the most carcinogenic mycotoxins which are harmful to animals and humans. In this study, 59 A. flavus isolates from four different habitats and 1 A. minisclerotigenes isolate were investigated. The isolates were identified and confirmed at the species level by the sequence analysis of a part of their calmodulin gene. Applying a combined analysis of UP-PCR, microsatellite, and calmodulin sequence data, the four group of isolates formed separate clusters on the phylogenetic tree. Examining the distribution of mating type genes MAT1-1 and MAT1-2, a ratio of approximately 3:1 was determined, and no correlation was found between the carried mating type gene and the aflatoxin production capability. HPLC analysis revealed that none of the examined isolates collected from indoor air or maize in Central Europe were able to produce aflatoxins, while about half of the isolates from India produced these mycotoxins under the test conditions.


Assuntos
Aspergillus flavus/classificação , Aspergillus flavus/isolamento & purificação , Genótipo , Aflatoxinas/genética , Aflatoxinas/metabolismo , Microbiologia do Ar , Animais , Aspergillus flavus/genética , Calmodulina/genética , DNA Fúngico , Ecossistema , Genes Fúngicos/genética , Humanos , Índia , Micotoxinas/genética , Filogenia , Análise de Sequência , Especificidade da Espécie , Zea mays/microbiologia
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