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1.
J Biol Inorg Chem ; 29(5): 477-498, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38995397

RESUMO

The global threat posed by antimicrobial resistance (AMR) to public health is an immensurable problem. The effectiveness of treating infections would be more at risk in the absence of effective antimicrobials. Researchers have shown an amplified interest in alternatives, such as developing advanced metallic nanohybrids as new therapeutic candidates for antibiotics due to their promising effectiveness against resistant microorganisms. In recent decades, the antimicrobial activity of monometallic nanoparticles has received extensive study and solid proof, providing new opportunities for developing multimetallic nanohybrid antimicrobials. Advanced metallic nanohybrids are an emerging remedy for a number of issues that develop in the field of medicine. Advanced metallic nanohybrids have shown a promising ability to combat resistant microorganisms due to their overall synergistic activity. Formulating advanced multimetallic nanohybrids falling under the umbrella of the growing field of nanoarchitectonics, which extends beyond nanotechnology. The underlying theory of nanoarchitectonics involves utilizing nanoscale units that follow the concepts of nanotechnology to architect nanomaterials. This review focuses on a comprehensive description of antimicrobial mechanisms of metallic nanohybrids and their enabling future insights on the research directions of developing the nanoarchitectonics of advanced multimetallic nanohybrids as novel antibiotics through their synergistic activity.


Assuntos
Antibacterianos , Antibacterianos/farmacologia , Antibacterianos/química , Nanopartículas Metálicas/química , Humanos , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Sinergismo Farmacológico , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química
2.
BMC Urol ; 24(1): 206, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39313789

RESUMO

Urinary tract infections (UTIs) pose a substantial burden on global healthcare systems. When unraveling the complex pathophysiology of UTIs, bladder models are used to understand complex and multifaceted interactions between different components within the system. This review aimed to bridge the gap between in vitro and in vivo experimental bladder models towards UTI research. We reviewed clinical, animal, and analytical studies and patents from 1959 to the end of 2023. Both in vivo and in vitro models offer unique benefits and drawbacks in understanding UTIs. In vitro models provide controlled environments for studying specific aspects of UTI biology and testing potential treatments, while in vivo models offer insights into how UTIs manifest and progress within living organisms. Thus, both types of models are leading to the development of more effective diagnostic tools and therapeutic interventions against UTIs. Moreover, advanced methodologies involving three-dimensional bladder organoids have also been used to study bladder biology, model bladder-related disorders, and explore new treatments for bladder cancers, UTIs, and urinary incontinence. Narrowing the distance between fundamental scientific research and practical medical applications, these pioneering models hold the key to unlocking new avenues for the development of personalized diagnostics, precision medicine, and ultimately, the alleviation of UTI-related morbidity worldwide.


Assuntos
Bexiga Urinária , Infecções Urinárias , Humanos , Animais , Modelos Animais de Doenças , Modelos Biológicos , Técnicas In Vitro
3.
Med Microbiol Immunol ; 210(4): 211-219, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34164720

RESUMO

The immune response is hypothesized as an important factor in the disease outcome of leptospirosis. Exaggerated immune response may promote tissue damage that lead to severe disease outcome. In this study TNF, IL-10, sTNFR1 levels were measured among sixty-two hospitalized leptospirosis confirmed patients in Sri Lanka. Thirty-one serum samples from healthy individuals were obtained as controls. PCR-RFLP method was used to identify TNF gene polymorphisms and to determine their association with TNF expression and disease severity in leptospirosis. TNF (p = 0.0022) and IL-10 (p < 0.0001) were found to be significantly elevated in leptospirosis patients, while sTNFR1 (p < 0.0001) was significantly suppressed. TNF was not significantly elevated in patients with complications while the anti-inflammatory cytokine IL-10 was significantly elevated among patients with complications (p = 0.0011) and with mortality (p = 0.0088). The ratio of IL-10 to TNF was higher among patients with complications (p = 0.0008) and in fatal cases (p = 0.0179). No association between TNF gene polymorphisms and TNF expression was detected due to the low frequency of heterozygous and mutated genes present in this study population. Thus the findings of the study show that elevated levels of IL-10 in the acute phase of disease could lead to severe outcomes and a high IL-10/TNF ratio is observed in patients with complications due to leptospirosis.


Assuntos
Interleucina-10/sangue , Leptospirose/sangue , Leptospirose/genética , Polimorfismo Genético , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética , Adulto , Citocinas/sangue , Feminino , Humanos , Interleucina-10/imunologia , Leptospirose/imunologia , Masculino , Pessoa de Meia-Idade , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Índice de Gravidade de Doença , Sri Lanka/epidemiologia , Fator de Necrose Tumoral alfa/imunologia
4.
J Wound Care ; 29(1): 12-15, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31930947

RESUMO

Chronically infected diabetic wounds have a polymicrobial aetiology. However, Salmonella Paratyphi A is a very rare cause of wound infection. A 76-year-old female patient with type II diabetes presented with a wound on the left leg of two months' duration. The wound was painful, erythematous and a thick, foul-smelling discharge was present. There was a history of delayed wound healing. Salmonella Paratyphi A and Pseudomonas aeruginosa were isolated from the wound tissue. The patient was treated with cefuroxime and cloxacillin empirically and following the antibiotic susceptibility testing (ABST) report, ciprofloxacin was given for 10 days. The wound was treated with multiple debridements and topical antiseptic. On follow-up, the patient remained afebrile with subsiding discharge from the ulcer. This is the first reported case of Salmonella Paratyphi A from an infected diabetic ulcer in Sri Lanka and it serves to further define the spectrum of illnesses caused by this uncommon pathogen.


Assuntos
Antibacterianos/administração & dosagem , Ciprofloxacina/administração & dosagem , Diabetes Mellitus Tipo 2/complicações , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Úlcera da Perna/microbiologia , Salmonella paratyphi A/isolamento & purificação , Idoso , Anti-Infecciosos Locais/administração & dosagem , Cefuroxima/administração & dosagem , Cloxacilina/administração & dosagem , Desbridamento , Feminino , Infecções por Bactérias Gram-Negativas/etiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Úlcera da Perna/etiologia , Úlcera da Perna/fisiopatologia , Testes de Sensibilidade Microbiana , Febre Paratifoide/tratamento farmacológico , Febre Paratifoide/etiologia , Febre Paratifoide/microbiologia , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/etiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Salmonella paratyphi A/efeitos dos fármacos , Cicatrização
5.
Acta Odontol Scand ; 77(7): 508-516, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31145647

RESUMO

Aims: Oral candidiasis is a major oral manifestation of uncontrolled diabetes mellitus, and a number of cofactors are associated with the pathogenesis of this infection. Here, we describe the prevalence of oral Candida in a Sri Lankan cohort of type 2 diabetes mellitus and risk factors that predispose them to this common fungal infection. Methods: A case-control study was conducted in 250 diabetics with type 2 diabetes and 81 nondiabetic controls. Clinical and demographic data were collected using an interviewer administered questionnaire, and patient records. Oral rinse samples were collected to determine the candidal carriage, and the resultant yeast growth was quantified and speciated using multiplex-PCR and phenotypic analyses. Chi-square test (χ2 test) and Fisher exact test were used for the determination of the significant relationships between risk factors and oral candidiasis. Results: The oral prevalence of Candida species among both groups was similar (81%) although a significantly higher proportion of diabetics (32.8%) yielded >2000 CFU/mL of yeasts compared with only 12.3% of the healthy controls (p < .05). Significant associations were noted between oral candidal carriage amongst diabetics, and (i) denture wearing, (ii) female gender and (iii) cigarette smoking (all, p < .05). Amongst both groups, C.albicans was the most common Candida species isolated followed by C. parapsilosis, C. tropicalis and C. glabrata. Conclusions: The oral infestation of Candida in our Sri Lankan cohort of diabetics is significantly higher than their healthy counterparts, and co-carriage of multiple yeast species is a common finding in the study population. As there are no previous such reports of the latter phenomenon particularly from the Asian region it is noteworthy, mainly in view of the recent data on the emergence of drug-resistant yeast species the world over.


Assuntos
Candida/isolamento & purificação , Candidíase Bucal/diagnóstico , Complicações do Diabetes , Diabetes Mellitus Tipo 2/diagnóstico , Adulto , Candida/classificação , Candida albicans/isolamento & purificação , Candidíase Bucal/epidemiologia , Candidíase Bucal/microbiologia , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/microbiologia , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco , Distribuição por Sexo , Sri Lanka/epidemiologia
6.
Med Princ Pract ; 28(1): 28-35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30352435

RESUMO

OBJECTIVE: Pseudomonas aeruginosa and Staphylococcus aureus dual-species biofilm infections are notoriously difficult to manage. This study aimed at investigating the influence of four different culture media on the planktonic growth, adhesion, and biofilm formation of P. aeruginosa and S. aureus. MATERIALS AND METHODS: We monitored four different culture media including Nutrient Broth, Brain Heart Infusion (BHI) broth, Luria-Bertani broth, and RPMI 1640 medium on the planktonic growth, adhesion, and biofilm formation of P. aeruginosa (ATCC 27853) and S. aureus (ATCC 25923) using MTT assay and scanning electron microscopy (SEM). RESULTS: The most robust growth of the mono- and dual-species cultures was noted in BHI broth. On the contrary, RPMI 1640 medium promoted maximal initial adhesion of both the mono- and dual-species, but BHI broth fostered the maximal biofilm growth. SEM images showed profuse extracellular polysaccharide production in biofilms, particularly in coculture, in BHI medium. CONCLUSION: Our data demonstrate that BHI broth, relative to the other tested media, is the most conducive for in vitro evaluation of biofilm and planktonic growth kinetics of these two pathogens, both in mono- and coculture.


Assuntos
Biofilmes/crescimento & desenvolvimento , Meios de Cultura , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Humanos , Técnicas Microbiológicas/métodos
7.
Microbiol Immunol ; 2018 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-29704402

RESUMO

Single nucleotide polymorphisms present on the promoter sequence of the TNF-α gene may affect production of TNF-α, a pro-inflammatory cytokine, during immune responses. The presence of TNF-α polymorphisms is also reportedly associated with more severe manifestations of Helicobacter pylori infection. However, the frequency of TNF-α polymorphisms and the associated disease severity vary between different patient groups. In this study, gastric biopsies and blood specimens were collected from 138 patients with dyspepsia undergoing routine upper gastrointestinal endoscopy. Our institution's Ethics Review Committee approved the study and written informed consent was obtained from all participants. The presence of H. pylori was confirmed histologically in all patients. The frequency of TNF-α polymorphisms in the study cohort was investigated using PCR-restriction fragment length polymorphism and expression of serum TNF-α quantitated using a commercial ELISA assay. The proportions of selected TNF-α polymorphisms (TNF-α -238, -308 and -863) were similar in H. pylori-positive and -negative patients. Homozygous mutations of TNF-α polymorphisms were rarely detected in the study group. There was a significant difference in TNF-α concentrations between patients with mild chronic gastritis and TNF-α -308 GG genotype and patients with moderate to severe chronic gastritis (P = 0.008). It was not possible to identify an association between these genotypes and disease severity because of the low frequency of heterozygous and homozygous mutated genes in Sri Lankan patients with dyspepsia.

8.
Can J Infect Dis Med Microbiol ; 2018: 9704532, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30123395

RESUMO

OBJECTIVES: The aim of this study was to determine the level of five different pro- and anti-inflammatory cytokines to study the inflammatory response of leptospirosis. MATERIALS AND METHODS: The serum cytokine levels of IL-10, IL-17A, IL-21, IL-23, and TNF-α were investigated in 57 patients with leptospirosis and 12 healthy controls using a commercially available ELISA kit (Mabtech, Sweden). Statistical analysis was done using Graphpad Prism. RESULTS: Elevation of serum IL-10 and IL-17A levels and significant elevation of serum IL-21 (p=0.002), IL-23 (p=0.002), and TNF-α (p=0.039) were observed among leptospirosis patients compared to the healthy control group. The two major complications observed among these patients were renal failure and liver involvement. Renal failure was significantly associated with elevation of IL-21 and IL-23, while patients with liver involvement had a significant elevation of IL-21, IL-23, and TNF-α. CONCLUSION: Elevation of IL-17A together with the significant elevation of IL-21 and IL-23 suggests a possible involvement of Th17 cells in the immunopathogenesis of leptospirosis.

9.
Acta Odontol Scand ; 75(2): 113-122, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27960572

RESUMO

OBJECTIVES: Oral candidiasis is being frequently recognized in patients with diabetes, and is associated with multiple pathogens including Candida albicans, Candida parapsilosis, Candida glabrata and Candida tropicalis. The aim of this study was to evaluate a usefulness of a Multiplex Polymerase Chain Reaction as a rapid diagnostic tool for identification of four oral Candida pathogens in patients with diabetes. MATERIALS AND METHODS: A multiplex PCR was optimized to identify four Candida species in concentrated oral rinse samples. Common reverse primer, ITS4 and four species-specific forward primers targeting ITS1 and ITS2 regions of yeast genome were used. Species-specific single amplicon were detected by agarose gel electrophoresis. Performance efficacy of multiplex PCR was compared with phenotypic identification. RESULTS: Out of 100 oral rinse samples, 72 were culture positive and of these 43 were at risk of oral Candida infection (>600cfu/ml). Multiple Candida species including C. albicans, C. parapsilosis and C. tropicalis were identified in 22 samples which had risk of oral Candida infection. In total, 85 patients were positive for Candida by multiplex PCR and of them 49 had multiple Candida species. All 43 colonized specimens were also positive by multiplex PCR. C. albicans was the most predominant organism (75/85) followed by C. parapsilosis (47/85), C. tropicalis (17/85) and C. glabrata (6/85). In specimens with multiple species, the two most common organisms were C. albicans and C. parapsilosis. Multiplex PCR yielded a sensitivity of 10 Candida cells/ml of oral rinse sample. CONCLUSIONS: Multiplex PCR is found to be rapid, sensitive and specific than phenotypic identification methods in discriminating multiple Candida species in oral rinse specimens.


Assuntos
Candida/isolamento & purificação , Candidíase Bucal/microbiologia , Diabetes Mellitus Tipo 2/microbiologia , Candida albicans/isolamento & purificação , Candida glabrata/isolamento & purificação , Candida tropicalis/isolamento & purificação , Contagem de Colônia Microbiana , DNA Fúngico , Feminino , Humanos , Masculino , Antissépticos Bucais , Reação em Cadeia da Polimerase/métodos
10.
Med Princ Pract ; 26(6): 554-560, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29131083

RESUMO

OBJECTIVE: To determine the effect of glucose, sucrose, and saccharin on growth, adhesion, and biofilm formation of Candida albicans and Candida tropicalis. MATERIALS AND METHODS: The growth rates of mono-cultures of planktonic C. albicans and C. tropicalis and 1:1 mixed co-cultures were determined in yeast nitrogen broth supplemented with 5% (30 mM) and 10% (60 mM) glucose, sucrose, and saccharin, using optical density measurements at 2-h intervals over a 14-h period. Adhesion and biofilm growth were performed and the growth quantified using a standard 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The biofilm architecture was visualized using scanning electron microscopy. One- and two-way analysis of variance (ANOVA) was performed to analyse the differences among multiple means. RESULTS: The highest planktonic growth was noted in 5% glucose after 14 h (p < 0.05). No significant planktonic growth was observed in either concentration of saccharin. Both the concentrations of glucose and sucrose elicited significantly increased adhesion from MTT activity of 0.017 to >0.019 in mono- as well as co-cultures (p < 0.05), whilst the lower concentration of saccharin significantly dampened the adhesion. Maximal biofilm growth was observed in both species with the lower concentration of sucrose (5%), although a similar concentration of saccharin abrogated biofilm development: the highest MTT value (>0.35) was obtained for glucose and the lowest (>0.15) for saccharin. CONCLUSION: In this study, glucose and sucrose accelerated the growth, adhesion, and biofilm formation of Candida species. However, the non-nutritive sweetener saccharin appeared to dampen, and in some instances suppress, these virulent attributes of Candida.


Assuntos
Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Adoçantes não Calóricos/farmacologia , Adoçantes Calóricos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Glucose/farmacologia , Humanos , Microscopia Eletrônica de Varredura , Plâncton/efeitos dos fármacos , Sacarina/farmacologia , Sacarose/farmacologia
11.
BMC Infect Dis ; 16(1): 446, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27554098

RESUMO

BACKGROUND: Leptospirosis is a globally emerging zoonotic disease and an important public health threat in developing countries. Diagnosis of leptospirosis is mainly based on clinical presentations in resource poor countries. World Health Organization (WHO) has introduced "Faine's criteria" for diagnosis of leptospirosis. This study was conducted to evaluate the usefulness of modified Faine's criteria (with amendment) 2012 to detect leptospirosis in resource poor settings. METHODS: Blood samples of 168 patients who fulfilled the inclusion criteria admitted between January 2013 to January 2014 were tested by a commercial immunochromatographic assay (Leptocheck WB, India), microscopic agglutination test (MAT) and polymerase chain reaction (PCR) methods. Leptospirosis was confirmed by a single MAT titre ≥1:400 and / or by a positive PCR. Diagnosis of leptospirosis was made using the clinical, epidemiological and laboratory data according to modified Faine's criteria (with amendment) 2012. RESULTS: Leptospirosis was confirmed in 39 % (n = 66) by MAT and/or PCR. When modified Faine's criteria (MAT ≥ 1.400 &/ or PCR), was evaluated against LERG confirmed cases sensitivity, specificity, positive predictive value and negative predictive values were 95.45 %, 56.86 %, 58.88 %, 95.08 % respectively. The modified Faine's criteria with rapid immunochromatographic assay only had a sensitivity, specificity, positive predictive value and negative predictive value 89.39 %, 58.82 %, 58.42 %, and 89.55 % respectively. CONCLUSION: The modified Faine's criteria which utilized only immunochromatographic assay (leptocheck IgM) in Part C was found to be useful tool for diagnosing leptospirosis in a resource poor setting.


Assuntos
Cromatografia de Afinidade/métodos , Leptospirose/diagnóstico , Reação em Cadeia da Polimerase/métodos , Testes de Aglutinação/métodos , Animais , Países em Desenvolvimento , Fazendeiros , Humanos , Leptospira/genética , Leptospira/patogenicidade , Leptospirose/etiologia , Sensibilidade e Especificidade , Sri Lanka , Organização Mundial da Saúde , Zoonoses/diagnóstico
12.
Mem Inst Oswaldo Cruz ; 111(11): 697-702, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27706381

RESUMO

As there are sparse data on the impact of growth media on the phenomenon of biofilm development for Candida we evaluated the efficacy of three culture media on growth, adhesion and biofilm formation of two pathogenic yeasts, Candida albicans and Candida tropicalis. The planktonic phase yeast growth, either as monocultures or mixed cultures, in sabouraud dextrose broth (SDB), yeast nitrogen base (YNB), and RPMI 1640 was compared, and adhesion as well as biofilm formation were monitored using MTT and crystal violet (CV) assays and scanning electron microscopy. Planktonic cells of C. albicans, C. tropicalis and their 1:1 co-culture showed maximal growth in SDB. C. albicans/C. tropicalis adhesion was significantly facilitated in RPMI 1640 although the YNB elicited the maximum growth for C. tropicalis. Similarly, the biofilm growth was uniformly higher for both species in RPMI 1640, and C. tropicalis was the slower biofilm former in all three media. Scanning electron microscopy images tended to confirm the results of MTT and CV assay. Taken together, our data indicate that researchers should pay heed to the choice of laboratory culture media when comparing relative planktonic/biofilm growth of Candida. There is also a need for standardisation of biofilm development media so as to facilitate cross comparisons between laboratories.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/fisiologia , Candida tropicalis/fisiologia , Meios de Cultura , Humanos , Microscopia Eletrônica de Varredura
13.
Acta Odontol Scand ; 74(7): 565-569, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27538681

RESUMO

OBJECTIVES: The study aimed to determine the proportion, known risk factors and etiology for Candida infection in leukoplakia lesions among patients with oral leukoplakia attending the Oral and Maxillofacial Clinic at a Tertiary Care Hospital in Sri Lanka. MATERIALS AND METHODS: Eighty clinically suspected oral leukoplakia patients were included. Two oral swabs each, from leukoplakia patients: one swab from the lesion and the other one from the contralateral unaffected corresponding area (as a control) were collected. Direct microscopy and culture followed by colony count and phenotypic identification were performed to identify pathogenic Candida species. RESULTS: Candida infection was seen in 47% of patients with oral leukoplakia. Candida albicans (94.7%) was the most common Candida species followed by Candida tropicalis (5.3%). Majority of Candida-infected lesions were seen in the buccal mucosa region. Alteration of taste (p = 0.021), having other oral lesions (p = 0.008), angular cheilitis (p = 0.024) and periodontitis (p = 0.041) showed a significant association with Candida-associated leukoplakia. Increasing age showed a significant tendency for Candida infection (p = 0.020). Smoking (p = 0.026) and betel-quid chewing (p = 0.006) were also found to be significantly associated, although alcohol consumption alone did not show a significant association. Oral leukoplakia patients who had all three habits: alcohol consumption, smoking and betel-quid chewing had a significant association with Candida infection (p = 0.004). CONCLUSIONS: Patients who had a combination of risk factors: smoking, betel-quid chewing and alcohol consumption were seen to have a significant association with Candida infection. Further betel-quid chewing alone and smoking singly was also significantly associated with Candida infection in oral leukoplakia.


Assuntos
Candidíase Bucal/complicações , Leucoplasia Oral/microbiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas , Areca , Candida/classificação , Candida albicans/isolamento & purificação , Candida tropicalis/isolamento & purificação , Queilite/microbiologia , Contagem de Colônia Microbiana , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/microbiologia , Micologia/métodos , Periodontite/microbiologia , Fenótipo , Saúde Pública , Fatores de Risco , Fumar , Distúrbios do Paladar/microbiologia
14.
Mem Inst Oswaldo Cruz ; 110(4): 485-91, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26061234

RESUMO

Leptospirosis is a re-emerging zoonotic disease all over the world, important in tropical and subtropical areas. A majority of leptospirosis infected patients present as subclinical or mild disease while 5-10% may develop severe infection requiring hospitalisation and critical care. It is possible that several factors, such as the infecting serovar, level of leptospiraemia, host genetic factors and host immune response, may be important in predisposition towards severe disease. Different Leptospira strains circulate in different geographical regions contributing to variable disease severity. Therefore, it is important to investigate the circulating strains at geographical locations during each outbreak for epidemiological studies and to support the clinical management of the patients. In this study immunochromatography, microscopic agglutination test and polymerase chain reaction were used to diagnose leptospirosis. Further restriction fragment length polymorphism and DNA sequencing methods were used to identify the circulating strains in two selected geographical regions of Sri Lanka. Leptospira interrogans, Leptospira borgpetersenii and Leptospira kirschneri strains were identified to be circulating in western and southern provinces. L. interrogans was the predominant species circulating in western and southern provinces in 2013 and its presence was mainly associated with renal failure.


Assuntos
Leptospira/genética , Leptospirose/microbiologia , Adolescente , Adulto , Testes de Aglutinação , Animais , Cromatografia de Afinidade , Feminino , Humanos , Leptospira/classificação , Leptospira/isolamento & purificação , Leptospira interrogans , Leptospirose/epidemiologia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Genético , Estudos Prospectivos , Análise de Sequência de DNA , Índice de Gravidade de Doença , Especificidade da Espécie , Sri Lanka/epidemiologia
15.
Biomater Adv ; 162: 213930, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38909600

RESUMO

An estimated 1.7 million fatalities and 150 million cases worldwide are attributed to fungal infections annually, that are in rise due to immunocompromised patient population. The challenges posed by traditional treatments can be addressed with the help of nanotechnology advancements. In this study, Co, Cu, and Ag-were doped into silica nanoparticles. Then the synthesized monometallic silica nanohybrids were combined to formulate heterometallic silica nanohybrids, characterized structurally and morphologically, compared, and evaluated for antifungal activity based on their individual and synergistic activity. The antifungal assays were conducted by using ATCC cultures of Candida albicans and QC samples of Trichophyton rubrum, Microsporum gypseum, and Aspergillus niger. The MIC (ranging from 49.00 to 1560.00 µg/mL), MFC (ranging from 197.00 to 3125.00 µg/mL), IC50 values (ranging from 31.10 to 400.80 µg/mL), and FICI of nanohybrids were determined and compared. Moreover, well diffusion assay was performed. ABTS assay and DPPH assay were conducted to investigate the radical scavenging activity (RSA) of nanohybrids. SEM analysis clearly evidenced the structural deformations of each fungal cells and spores due to the treatment with trimetallic nanohybrid. According to the results, the trimetallic silica nanohybrids exhibited the most powerful synergistic RSA and the most effective antifungal activity, compared to the bimetallic silica nanohybrids.


Assuntos
Antifúngicos , Candida albicans , Testes de Sensibilidade Microbiana , Dióxido de Silício , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/síntese química , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Candida albicans/efeitos dos fármacos , Aspergillus niger/efeitos dos fármacos , Nanopartículas/química , Microsporum/efeitos dos fármacos , Sinergismo Farmacológico , Cobre/química , Cobre/farmacologia , Prata/farmacologia , Prata/química , Arthrodermataceae
16.
Indian J Med Microbiol ; 49: 100617, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38763381

RESUMO

PURPOSE: This study investigated to detect serotypes and virulence genes of Group B Streptococcus (GBS) isolated from pregnant women. METHODS: Forty-five samples of GBS isolates from January to August 2019 at antenatal clinics of 4 teaching hospitals in Western Province, Sri Lanka were included. Isolated GBS were carried to identify 9 serotypes by multiplex PCR. Different virulence determinants, including bac, rib and scp(B) have been detected by PCR. RESULTS: Among GBS-positive culture isolates most abundant serotype detected was type III 12/45 (26.7%) while serotype VII, VIII and IX were not seen. Furthermore, serotype Ia (15.6%); II (20%); V (17.8%); VI (15.6%); Ib (2.2%) and IV (2.2%) were identified. Among 5 rectal isolates, 1 isolate was serotype Ia, 2 isolates were serotype II and 2 isolates were serotype III. Forty (40/45) isolates expressed scpB gene (88.8%). Presence of rib gene was confirmed in 17.8%, bac in 13.3% isolates. ScpB, rib and bac were identified in 4.4% isolates, 8.9% isolates were scpB, rib positive and bac negative, 8.9% isolates were scpB, bac positive and rib negative. These three-virulence genes did not express in 8.9% isolates. ScpB gene was found once in serotype Ib and IV and all serotype VI expressed scpB gene. Rib gene was more common among serotype II and it was not found in serotype Ib, IV and VI. Bac gene was more common in serotype V and it was not found in serotype Ia, Ib and IV. There was not significant association between serotypes and virulence gene (p > 0.05). CONCLUSION: Serotype III is the most abundant serotype. In formulation of vaccine against GBS for Sri Lanka, serotype III should be targeted. Prevalence of vaccine candidate virulence protein such as ß antigens of the C protein (bac) and surface protein Rib (rib) genes were low in this study.


Assuntos
Sorogrupo , Infecções Estreptocócicas , Streptococcus agalactiae , Centros de Atenção Terciária , Fatores de Virulência , Streptococcus agalactiae/genética , Streptococcus agalactiae/patogenicidade , Streptococcus agalactiae/classificação , Streptococcus agalactiae/isolamento & purificação , Humanos , Feminino , Sri Lanka/epidemiologia , Fatores de Virulência/genética , Gravidez , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/epidemiologia , Adulto , Complicações Infecciosas na Gravidez/microbiologia
17.
ACS Omega ; 9(24): 26568-26581, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38911717

RESUMO

Postharvest loss is a significant global challenge that needs to be urgently addressed to sustain food systems. This study describes a simple microwave-assisted green synthesis method in developing a nanohybrid material combining natural ilmenite (FeTiO3) and graphene oxide (GO) as a promising antimicrobial fruit peel coating to reduce postharvest loss. The natural ilmenite was calcined in an inert environment and was mixed with GO in a microwave reactor to obtain the nanohybrid. The nanohybrid was then incorporated into an alginate biopolymer to form the fruit coating. Microscopic images revealed successful grafting of FeTiO3 nanoparticles onto the GO sheets. Spectroscopic measurements of Raman, X-ray photoemission, and infrared provided insights into the interactions between the two matrices. The optical band gap calculated from Tauc's relation using UV-vis data showed a significant reduction in the band gap of the hybrid compared to that of natural ilmenite. The antimicrobial activity was assessed using Escherichia coli, which showed a substantial decrease in colony counts. Bananas coated with the nanohybrid showed a doubling in the shelf life compared with uncoated fruits. Consistent with this, the electronic nose (E-nose) measurements and freshness indicator tests revealed less deterioration of the physicochemical properties of the coated bananas. Overall, the results show promising applications for the ilmenite-grafted GO nanohybrid as a food coating capable of minimizing food spoilage due to microbial activity.

18.
Iran J Basic Med Sci ; 26(9): 979-986, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37605731

RESUMO

Hygrophila schulli which is known as "Neermulli'' in the vernacular is an herbaceous plant native to Sri Lanka. Ancient medicinal literature suggests the use of H. schulli whole plant or its parts for the treatment of different communicable and non-communicable diseases including diabetes mellitus and tuberculosis. Active constituents and secondary metabolites including alkaloids, tannins, steroids, proteins, flavonoids, and glycosides are identified to possess antimicrobial, antitumor, antioxidant, hepatoprotective, anthelmintic, nephroprotective, antidiabetic, anticataract, anti-inflammatory, anti-nociceptive, hematopoietic, diuretic, antiurolithiatic, antipyretic, neuroprotection, and anti-endotoxin activities. In this review, we reviewed clinical studies, patents, and analytical studies from the earliest found examples from 1886 to the end of 2021. We critically analyzed and attempt to summarize the information based on bioactivities and chemical composition of H. schulli plant extracts which will be of future use for researchers in this field.

19.
Indian J Med Microbiol ; 42: 71-76, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36400647

RESUMO

PURPOSE: This study was conducted to determine the biofilm formation of coagulase negative Staphylococcus species (CoNS) isolated from patients with catheter related blood stream infection (CRBSI) and colonized central venous catheters (CVC) and their antibiotic susceptibility patterns and in situ biofilm formation of CVC tips. METHODS: Eighty-two CoNS isolated from intensive care unit (ICU) patients with CRBSI (n â€‹= â€‹8) or colonized CVC (n â€‹= â€‹74) were included. Species identification and antibiotic susceptibility test were done. All isolates were screened for biofilm formation using crystal violet and 3-(4,5-dimethylthiazole-2-yl)-2-5-diphenyl-2H-tetrazolium bromide (MTT) assays and categorized as strong or moderate biofilm formers. CVC tips were subjected to crystal violet stain and scanning electron microscopy (SEM) to detect in-situ biofilm formation. RESULTS: Staphylococcus haemolyticus (n â€‹= â€‹34; 41%) was the commonest to cause both CRBSI and CVC colonization. All 82 CoNS produced biofilms. Among them 77 (93.90%) were strong biofilm formers including all from CRBSI patients and 05 (6.10%) were moderate biofilm formers as detected by both methods. SEM showed bacteria adhered to surfaces of CVC tips with microbial-aggregates embedded in extracellular matrix. Mean crystal violet absorbance of CVC from CRBSI patients (0.6628) was significantly higher than colonized CVC (mean value 0.5592) (p â€‹= â€‹0.030). S. haemolyticus showed higher resistance to cloxacillin compared to other CoNS (p â€‹= â€‹0.039). CONCLUSION: Majority of CoNS isolated were strong biofilm formers. In-situ biofilm formation on CVC tips were significantly evident in CRBSI patients compared to CVC colonized patients. S. haemolyticus is the commonest to cause both CRBSI and CVC colonization and shows significantly higher cloxacillin resistance rate.


Assuntos
Infecções Relacionadas a Cateter , Cateteres Venosos Centrais , Humanos , Cateteres Venosos Centrais/efeitos adversos , Coagulase , Violeta Genciana , Infecções Relacionadas a Cateter/microbiologia , Staphylococcus , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Resistência Microbiana a Medicamentos , Unidades de Terapia Intensiva , Cloxacilina , Biofilmes
20.
Cancers (Basel) ; 15(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36900301

RESUMO

The incidence of oral squamous cell carcinoma (OSCC), and its precursor, oral epithelial dysplasia (OED), is on the rise, especially in South Asia. OSCC is the leading cancer in males in Sri Lanka, with >80% diagnosed at advanced clinical stages. Early detection is paramount to improve patient outcome, and saliva testing is a promising non-invasive tool. The aim of this study was to assess salivary interleukins (lL1ß, IL6, and IL8) in OSCC, OED and disease-free controls in a Sri Lankan study cohort. A case-control study with OSCC (n = 37), OED (n = 30) patients and disease-free controls (n = 30) was conducted. Salivary lL1ß, IL6, and IL8 were quantified using enzyme-linked immuno-sorbent assay. Comparisons between different diagnostic groups and potential correlations to risk factors were assessed. Salivary levels for the three tested interleukins increased from disease-free controls through OED, and were highest in OSCC samples. Furthermore, the levels of IL1ß, IL6, and IL8 increased progressively with OED grade. The discrimination between patients (OSCC and OED) and controls, as assessed by AUC of receiver operating characteristic curves, was 0.9 for IL8 (p = 0.0001) and 0.8 for IL6 (p = 0.0001), while IL1ß differentiated OSCC from controls (AUC 0.7, p = 0.006). No significant associations were found between salivary interleukin levels and smoking, alcohol, and betel quid risk factors. Our findings suggest that salivary IL1ß, IL6, and IL8 are associated with disease severity of OED, and are potential biomarkers for predicting disease progression in OED, and the screening of OSCC.

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