Abstract：
:Escherichia coli causes various ailments such as septicemia, enteritis, foodborne illnesses, and urinary tract infections which are of concern in the public health field due to antibiotic resistance. Silver nanoparticles (AgNP) are known for their biocompatibility and antibacterial activity, and may prove to be an alternative method of treatment, especially as wound dressings. In this study, we compared the antibacterial efficacy of two polymer-coated silver nanoparticles either containing 10% Ag (Ag 10% + Polymer), or 99% Ag (AgPVP) in relation to plain uncoated silver nanoparticles (AgNP). Atomic force microscopy was used to characterize the nanoparticles, and their antibacterial efficacy was compared by the minimum inhibitory concentration (MIC) and bacterial growth curve assays, followed by molecular studies using scanning electron microscopy (SEM) and (qRT- PCR). AgNP inhibited the growth of E. coli only at 0.621 mg/mL, which was double the concentration required for both coated nanoparticles (0.312 mg/mL). Similarly, bacterial growth was impeded as early as 8 h at 0.156 mg/mL of both coated nanoparticles as compared to 0.312 mg/mL for plain AgNP. SEM data showed that nanoparticles damaged the cell membrane, resulting in bacterial cell lysis, expulsion of cellular contents, and complete disintegration of some cells. The expression of genes associated with the TCA cycle (aceF and frdB) and amino acid metabolism (gadB, metL, argC) were substantially downregulated in E. coli treated with nanoparticles. The reduction in the silver ion (Ag+) concentration of polymer-coated AgNP did not affect their antibacterial efficacy against E. coli.
journal_name
Rev Inst Med Trop Sao Paulojournal_title
Revista do Instituto de Medicina Tropical de Sao Pauloauthors
Ashmore D,Chaudhari A,Barlow B,Barlow B,Harper T,Vig K,Miller M,Singh S,Nelson E,Pillai Sdoi
10.1590/s1678-9946201860018subject
Has Abstractpub_date
2018-01-01 00:00:00pages
e18eissn
0036-4665issn
1678-9946pii
S0036-46652018005000209journal_volume
60pub_type
杂志文章abstract：:A comparative study of the "in vitro" susceptibility of 24 Cryptococcus strains to 5 antifungal drugs (amphotericin B, 5 fluorocytosine, miconazole, itraconazole and ketoconazole), was carried out. These strains were grouped according to species, varieties and isolation's origins. The minimum inhibitory concentration ...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46651989000500009
更新日期：1989-09-01 00:00:00
abstract：:Cystic echinococcosis (CE) is a globally parasitic zoonosis caused by larval stages of Echinococcus granulosus. This study investigated E. granulosus genotypes isolated from livestock and humans in the Golestan province, northern Iran, southeast of the Caspian sea, using partial sequencing data of the cytochrome c oxi...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/S1678-9946201658038
更新日期：2016-01-01 00:00:00
abstract：:Twenty seven cases of neurocysticercosis, with clinical picture of acute meningitis, are described. Twenty (74.1%) patients are male; the age was 4 to 42 years (23.6 +/- 11.7 years). The etiologic diagnosis was defined by the complement fixation test (Weinberg) and/or enzyme-linked immunosorbent assay (ELISA) for cyst...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：
更新日期：1994-01-01 00:00:00
abstract：:Envenomation by coral snakes (Micrurus sp.) is one of the most dangerous injuries in America and it is considered as a serious medical emergency, however bites by these snakes appear to be rare. We analyzed epidemiological data, clinical signs and antivenom use in Argentina during the period between 1979-2003. During ...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652013000100003
更新日期：2013-01-01 00:00:00
abstract：:The aim of the present work was to determine the prevalence of IgG and IgM anti-Toxoplasma gondii antibodies and the factors associated to the infection in pregnant women attended in Basic Health Units in Rolândia, Paraná, Brazil. The sample was divided in two groups: group I (320 pregnant women who were analyzed from...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652011000400002
更新日期：2011-07-01 00:00:00
abstract：:We report a case of a 42 year-old female, who came to a leishmaniasis reference center in Rio de Janeiro, Brazil, presenting a cutaneous leishmaniasis lesion in the right forearm. Treatment with low-dose intramuscular meglumine antimoniate (MA) (5 mg Sb5+/kg/day) was initiated, with improvement after 28 days, although...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652014000400016
更新日期：2014-07-01 00:00:00
abstract：:The availability of an ultramicroanalytic system (SUMA) and species-specific antigen of M. leprae obtained by chemical synthesis, have made possible the standardization and validation of an ultramicroELISA assay for detecting specific human IgM antibodies to this mycobacterium. The specificity of this test to demonstr...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：
更新日期：1991-11-01 00:00:00
abstract：:The insecticidal effect of six commercially available plant oils was tested against 4th larval instars of Culex pipiens. Larvae were originally collected from Meit El-Attar, Qalyubia Governorate, Egypt, and then reared in the laboratory until F1 generation. The LC50 values were 32.42, 47.17, 71.37, 83.36, 86.06, and 1...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652008000200008
更新日期：2008-03-01 00:00:00
abstract：:A proven case of human infection caused by Angiostrongylus costaricensis is reported for the first time in Venezuela. The patient was a 57-year-old female surgically operated because of signs of peritonitis with a palpable mass at the lower right quadrant of the abdomen. WBC count reported 16,600 cells/mm3, with 46% e...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章,评审
doi：10.1590/s0036-46652007000300012
更新日期：2007-05-01 00:00:00
abstract：:We report the first case of human ocular sparganosis in the state of Santa Catarina, southern Brazil. A young female patient presented with three periocular moveable inflammatory masses in her right eye, during two years. By surgical excisional biopsy, a helminth larval stage was removed and identified as sparganum. C...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652011000100009
更新日期：2011-01-01 00:00:00
abstract：:Publications are often used as a measure of research work success. Human T-lymphotropic virus (HTLV) type 1 and 2 are human retroviruses, which were discovered in the early 1980s, and it is estimated that 15-20 million people are infected worldwide. This article describes a bibliometric review and a coauthorship netwo...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/S1678-9946201658011
更新日期：2016-01-01 00:00:00
abstract：:A cross-sectional study was carried out among 996 volunteer blood donors enrolled from May 1999 to December 1999 to determine the seroprevalence of hepatitis E virus (HEV) infection among volunteer blood donors of the Regional Blood Bank of Londrina, State of Paraná, Brazil, and to evaluate whether the rate of seropre...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652006000200006
更新日期：2006-03-01 00:00:00
abstract：:Leptospirosis is a reemerging zoonosis caused by bacteria of the genus Leptospira sp. with global importance in the medical and veterinary fields, being responsible for about 59 thousand deaths each year in the world. The use of Geographic Information Systems (GIS) in the health sector is propitious and has been adopt...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/S1678-9946202062035
更新日期：2020-06-05 00:00:00
abstract：:Three autochthonous cases of cutaneous-ganglionar rickettsiosis transmitted by dogs ticks (Amblyomma maculatum in one of them) are reported. Two of the three cases were undoubtely produced by Rickettsia conorii according to the results of the specific indirect immunofluorescence technique IEF-IgM anti R. conorii. A th...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46651990000500001
更新日期：1990-09-01 00:00:00
abstract：:The Authors report a case of paracoccidioidomycosis in a Surui Indian patient from the state of Rondonia, Brazilian Amazon. The subject is an adult male, having been diagnosed on the basis of mycologic, serologic, and radiographic exams. The prescribed therapy was sulphamethoxazole 800 mg associated with trimethoprim ...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：
更新日期：1991-09-01 00:00:00
abstract：:Two cases of spontaneous bacterial peritonitis (SBP) caused by Listeria monocytogenes in cirrhotic patients are reported. In one of the cases, the microorganism was isolated from pleural effusion and ascites. SBP is a serious and common complication of patients with ascites caused by hepatic cirrhosis and the culture ...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652006000500010
更新日期：2006-09-01 00:00:00
abstract：:In order to study the chemoresistance of Plasmodium falciparum to commonly used antimalarial drugs in Brazil the authors have studied ten patients with falciparum malaria, acquired in the Brazilian Amazon region. Patients were submitted to in vivo study of drug sensitivity, after chemotherapy with either 4-aminoquinol...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46651997000200004
更新日期：1997-03-01 00:00:00
abstract：:A total of 73 isolates (57 Enterobacter cloacae and 16 Enterobacter agglomerans), recovered during an outbreak of bacteremia in the Campinas area, São Paulo, Brazil, were studied. Of these isolates, 61 were from parenteral nutrition solutions, 9 from blood cultures, 2 from a sealed bottle of parenteral nutrition solut...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652000000100001
更新日期：2000-01-01 00:00:00
abstract：:An E.L.I.S.A. test for antibody detection, with an exo-antigen of Coccidioides immitis was standardized in 67 humans sera diluted in 1/1000, 1/2000, 1/4000 and 1/8000. Eighteen sera from mycologically proved cases of coccidioidomycosis were studied: 5 were negative and 13 were positive in some dilutions. 3/26 sera of ...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46651991000400007
更新日期：1991-07-01 00:00:00
abstract：:Infrapopliteal mycotic aneurysm resulting from endocarditis is rare, with only a few reported cases. We describe the case of a 28-year-old male patient who was suffering with pain and edema in the right leg. The ultrasound revealed an aneurysm of the right tibioperoneal trunk and a deep vein thrombosis (DVT). The pati...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652012000300010
更新日期：2012-05-01 00:00:00
abstract：:Thirty Candida albicans isolated from oral candidosis patients and 30 C. albicans isolated from control individuals were studied. In vitro susceptibility tests were performed for amphotericin B, fluconazole, 5-flucytosine and itraconazole through the Clinical and Laboratorial Standards Institute (CLSI) reference metho...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652008000100002
更新日期：2008-01-01 00:00:00
abstract：:In order to better understand the biology of Centrocestus formosanus in a definitive host model, mice of Swiss and AKR/J strains were experimentally infected with 100 metacercariae of the parasite. Fourteen days post-infection, the rodents were killed and adult trematodes were recovered from the small intestine. The p...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652013000200013
更新日期：2013-03-01 00:00:00
abstract：:The dissemination of the giant African snail Achatina fulica in several countries has triggered a great number of studies on the mollusk, including those on zoonoses related to health in humans. The current research is a scientific survey on articles published in four databases, namely, PubMed, Bireme, Scielo and Lila...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/S1678-9946201759015
更新日期：2017-04-13 00:00:00
abstract：:We all hope that biotechnology will answer some social and economical unavoidable requirements of the modern life. It is necessary to improve agriculture production, food abundance and health quality in a sustainable development. It is indeed a hard task to keep the progress on taking into account the rational use of ...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 历史文章,杂志文章
doi：10.1590/s0036-46652001000400006
更新日期：2001-07-01 00:00:00
abstract：:In view of the high circulation of migratory birds and the environmental and climatic conditions which favor the proliferation of arthropods, the Brazilian Pantanal is susceptible to circulation of arboviruses. However, the amount of data concerning arbovirus vectors in this area is scarce; therefore the aim of this s...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652010000100003
更新日期：2010-01-01 00:00:00
abstract：:Among the 424 serum samples examined, the prevalence of hepatitis virus infection turned out to be 89.6%, with 15.6% of HBsAg positivity. Some of the samples belonged to an afferent population and some other to workers of a West Africa rural hospital (Pop. Rep. of Benin). 27.3% of the positive subjects presented activ...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46651990000100006
更新日期：1990-01-01 00:00:00
abstract：:The municipality of Cantagalo is an area with sustained transmission of American Cutaneous Leishmaniasis (ACL). Monthly sand fly collections were performed for three years (June 2012 - May 2015) using a CDC light trap. A total of 3,310 specimens belonging to 12 species were trapped: Nyssomyia intermedia, Nyssomyia whi...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/S1678-9946201658050
更新日期：2016-07-11 00:00:00
abstract：:Systemic fungal infections are responsible for high mortality rates. Several species of fungi may be involved, but Candida spp. is the most prevalent. Simvastatin is used to lower cholesterol and also exhibits antifungal action. The aim of this study was to evaluate the synergistic action of simvastatin with fluconazo...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46652012000400003
更新日期：2012-08-01 00:00:00
abstract：:Cryo-microtome sections of larvae of Strongyloides stercoralis and S. ratti respectively obtained from human and rat feces cultures, were used as antigens. Fluoresceinate conjugates against human IgG were employed at the ideal titer of 10 for S. stercoralis and 100 for S. ratti. The sensitivity of the indirect immunof...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46651997000600001
更新日期：1997-11-01 00:00:00
abstract：:This paper reports a case of peritonitis by Nocardia asteroides during continuous ambulatory peritoneal dialysis in a man who had systemic lupus erythematous and chronic renal failure. Diagnosis was established by microscopic examination (Gram and Kinyoun) and culture of centrifuged dialysis fluid and the patient was ...
journal_title：Revista do Instituto de Medicina Tropical de Sao Paulo
pub_type： 杂志文章
doi：10.1590/s0036-46651993000400013
更新日期：1993-07-01 00:00:00
