scholarly journals Microbial Analysis of Contact Lenses

2021 ◽  
pp. 124-131
Author(s):  
Hemaanhini Tamilmani ◽  
N. P. Muralidharan
Keyword(s):  
Saline Solution ◽  
Contact Lenses ◽  
Fungal Infections ◽  
Fungal Growth ◽  
Blood Agar ◽  
Coagulase Negative Staphylococci ◽  
Eye Infections ◽  
Sterile Saline ◽  
Colony Forming Unit ◽  
Microbial Analysis

Introduction: Contact lenses are small, thin lenses which are worn directly on the surface of the eyes. They can be worn aesthetically or to correct vision. Contact lens related eye infections can lead to serious complications such as blindness, and are associated with several risk factors such as sleeping with lenses, exposure to water, not adhering to replacement schedules, and reusing disinfecting solutions, among others. The severity of the infection may vary with the degree of pathogenicity of the microorganism. Hygiene and handling of contact lenses play a very important role. The main aim of this study is to assess the microbial analysis of contact lenses. Materials and Methods: A total of 15 lenses were collected in 2 ml sterile saline solution individually and manually agitated for five minutes. The lens was then removed using a sterile toothpick from the container. The sterile container was stored at 4°C till it was processed. 50 microliter of the sample was transferred using a pipette and inoculated on nutrient agar, blood agar and sabouraud dextrose agar. The microorganism (fungus or bacteria) were identified by standard protocol. Results and Discussion: Bacillus, Staphylococcus aureus and CONS [Coagulase Negative Staphylococci] were found in blood agar. No fungal growth was found among the samples. More importance could be given to contact lenses handling and hygiene to avoid eye related bacterial and fungal infections. Conclusion: In the present study, the total CFU (Colony Forming Unit) was found to be confluent in all the participants who wore contact lenses for 4 months compared to those who have worn contact lenses from 15 and 28 days. Only bacterial growth was seen in the culture plate. There was no fungal growth seen from the samples collected.

Bacterial and Fungal Keratitis: A Retrospective Analysis at a University Hospital in Switzerland

2019 ◽  
Vol 236 (04) ◽  
pp. 358-365 ◽  
Author(s):  
Alexandra Bograd ◽  
Theo Seiler ◽  
Sara Droz ◽  
Stefan Zimmerli ◽  
Beatrice Früh ◽  
...  
Keyword(s):  
Contact Lenses ◽  
Topical Therapy ◽  
Fungal Growth ◽  
Fungal Keratitis ◽  
University Hospital ◽  
Fusarium Spp ◽  
Candida Spp ◽  
Coagulase Negative Staphylococci ◽  
History Of ◽  
Time Periods

Abstract Background Infectious keratitis is a serious corneal disease and may lead to permanent visual deterioration if not treated rapidly and effectively. In order to determine possible changes in the spectrum of pathogens over time, we evaluated the pathogenic organisms of keratitis at a university hospital in Switzerland, comparing two time periods within a decade. Methods In this retrospective study, 417 patients with the clinical diagnosis of bacterial or fungal keratitis in 2006/07 and 2015/16 were enrolled. In an additional analysis, all cases of fungal keratitis between 2006 and 2016 were evaluated. Collected parameters were age, gender, side, use of contact lenses, systemic, neurological and ocular diseases, trauma, previous surgery, and systemic and topical therapy before presentation. In each patient, microbiological results of corneal smears such as growth and antibiotic resistance were analysed. Results A total of 163 and 254 eyes were included in 2006/07 and 2015/16, respectively. In 2006/07, a culture of smears revealed a bacterial cause in 70 eyes (42.9%) and a fungal cause in 4 eyes (2.5%), whereas in 2015/16, bacterial growth was found in 115 eyes (45.3%) and fungal growth in 6 eyes (2.4%). The most common bacteria in 2006/07 and 2015/16 were coagulase-negative Staphylococci (44.3 vs. 49.6%), Pseudomonas aeruginosa (18.6 vs. 13.9%), Staphylococcus aureus (10 vs. 16.5%), Corynebacterium spp. (8.6 vs. 5.2%), and Moraxella spp. (7.1 vs. 9.6%). Candida parapsilosis was the most common fungal isolate in both groups (25 vs. 33.3%). Between 2006 and 2016, fungal keratitis was found in 37 eyes (Candida spp. n = 11, Fusarium spp. n = 11, Aspergillus spp. n = 5, others n = 10). All patients with Fusarium spp. keratitis had a history of wearing contact lenses. Conclusion The most commonly isolated bacterial organisms were Staphylococci and Pseudomonas spp., whereas fungal keratitis was mainly due to Candida spp. or Fusarium spp. No relevant variation in causative pathogens was observed between the two time periods.

scholarly journals Influence of local tetracycline on the microbiota of alveolar osteitis in rats

2008 ◽  
Vol 19 (2) ◽  
pp. 119-123 ◽  
Author(s):  
Joseane Maria Dias Bosco ◽  
Sérgio Ricardo de Oliveira ◽  
Álvaro Francisco Bosco ◽  
Christiane Marie Schweitzer ◽  
Elerson Gaetti Jardim Júnior
Keyword(s):  
Aqueous Solution ◽  
Wistar Rats ◽  
Blood Agar ◽  
Selective Media ◽  
Sterile Saline ◽  
Alveolar Osteitis ◽  
Microbial Samples

The aim of the present study was to evaluate the effects of local tetracycline on the occurrence of alveolar osteitis in rats, and on the microbiota associated to this infection. Forty Wistar rats were randomly assigned to 4 groups (n=10): I - the rats had the maxillary right incisor extracted and the alveolar wound did not receive any treatment; II - adrenaline and Ringer-PRAS were introduced into the alveolar wound; III - the alveolar wound was irrigated with sterile saline; and IV - the alveolar wound was irrigated with an aqueous solution of tetracycline. Microbial samples from the alveolar wounds were collected 2 days after surgery and inoculated on blood agar (with and without 8 µg/mL of tetracycline) and other selective media, and were incubated in either aerobiosis or anaerobiosis at 37ºC, for 2 to 14 days. It was verified that tetracycline reduced the occurrence of alveolar osteitis in the rats and caused significant changes in the microbiota of the surgical sites, decreasing the number of anaerobes and increasing the participation of tetracycline-resistant and multi-resistant microorganisms.

scholarly journals CD137 Signaling Is Critical in Fungal Clearance during Systemic Candida albicans Infection

2021 ◽  
Vol 7 (5) ◽  
pp. 382
Author(s):  
Vuvi G. Tran ◽  
Na N. Z. Nguyen ◽  
Byungsuk Kwon
Keyword(s):  
Candida Albicans ◽  
Defense Mechanisms ◽  
Tumor Necrosis ◽  
Fungal Infections ◽  
Fungal Growth ◽  
Wild Type ◽  
Agonistic Antibody ◽  
Innate Defense ◽  
Surface Receptor ◽  
Candida Albicans Infection

Invasive fungal infections by Candida albicans frequently cause mortality in immunocompromised patients. Neutrophils are particularly important for fungal clearance during systemic C. albican infection, yet little has been known regarding which surface receptor controls neutrophils’ antifungal activities. CD137, which is encoded by Tnfrsf9, belongs to the tumor necrosis receptor superfamily and has been shown to regulate neutrophils in Gram-positive bacterial infection. Here, we used genetic and immunological tools to probe the involvement of neutrophil CD137 signaling in innate defense mechanisms against systemic C. albicans infection. We first found that Tnfrsf9−/− mice were susceptible to C. albicans infection, whereas injection of anti-CD137 agonistic antibody protected the host from infection, suggesting that CD137 signaling is indispensable for innate immunity against C. albicans infection. Priming of isolated neutrophils with anti-CD137 antibody promoted their phagocytic and fungicidal activities through phospholipase C. In addition, injection of anti-CD137 antibody significantly augmented restriction of fungal growth in Tnfrsf9−/− mice that received wild-type (WT) neutrophils. In conclusion, our results demonstrate that CD137 signaling contributes to defense mechanisms against systemic C. albicans infection by promoting rapid fungal clearance.

scholarly journals Rapidly dissolving microneedle patch of amphotericin B for intracorneal fungal infections

2021 ◽  
Author(s):  
Alyaa A. Albadr ◽  
Ismaiel A. Tekko ◽  
Lalitkumar K. Vora ◽  
Ahlam A. Ali ◽  
Garry Laverty ◽  
...  
Keyword(s):  
Fungal Infection ◽  
Amphotericin B ◽  
Fungal Infections ◽  
Fungal Growth ◽  
Significant Inhibition ◽  
Corneal Tissue ◽  
Biodegradable Poly ◽  
Invasive Method ◽  
Poorly Soluble ◽  
Microneedle Patch

AbstractChronic fungal infection of the cornea could lead to blindness if not treated properly. Topical amphotericin B (AMP-B) is considered the first treatment of choice for ocular fungal infection. However, factors related to its poor solubility and penetration through intact cornea lead to poor bioavailability. Microneedles (MNs) are emerging as a minimally invasive method to enhance ocular drug delivery. This study aims to investigate the potential use of biodegradable poly(vinylpyrrolidone) (PVP) and hyaluronic acid (HA)–based rapidly dissolving MNs for delivery of AMP-B to treat fungal infection. The data obtained illustrates PVP/HA MN arrays’ reproducibility, good mechanical strength, and faster dissolution with 100% drug recovery. Multiphoton microscopic results revealed that MNs successfully penetrate the corneal tissue and enhance AMP-B permeation through corneal layers. Furthermore, PVP/HA MN arrays showed high solubility. Both PVP and HA successfully decreased AMP-B cytotoxicity when compared to free drug. More interestingly, the biocompatible MN formulations preserved the antifungal activity of AMP-B, as demonstrated by significant inhibition of fungal growth. Therefore, this study shows the feasibility of ocular delivery of the poorly soluble AMP-B using a fast-dissolving MN patch. Graphical abstract

Which Type of Saline Solution for Soft Contact Lenses is Best?

1981 ◽  
Vol 91 (4) ◽  
pp. 540-542
Author(s):  
Frederick T. Fraunfelder ◽  
J. Richard Crout
Keyword(s):  
Saline Solution ◽  
Contact Lenses ◽  
Soft Contact ◽  
Soft Contact Lenses

scholarly journals Case Study: Misdiagnosis of Nonhemolytic Staphylococcus aureus Isolates from Cases of Bovine Mastitis as Coagulase-Negative Staphylococci

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 252
Author(s):  
Valerie E. Ryman ◽  
Felicia M. Kautz ◽  
Steve C. Nickerson
Keyword(s):  
Staphylococcus Aureus ◽  
Bovine Mastitis ◽  
Dairy Farm ◽  
Blood Agar ◽  
Coagulase Negative Staphylococci ◽  
Mannitol Salt Agar ◽  
Lactating Cows ◽  
Presumptive Identification ◽  
Microbiological Techniques

Staphylococcus aureus is one of the most concerning mastitis-causing pathogens in dairy cattle. Using basic microbiological techniques, S. aureus is typically identified by colony characteristics and hemolysis on blood agar where isolates without hemolysis are typically considered to be coagulase-negative staphylococci (CNS) isolates. Herein, we present a decade-long case study where suspected S. aureus isolates from one Georgia dairy farm were further tested to confirm presumptive identification. Presumptive identification of bacterial growth from 222 mammary secretions from bred Holstein heifers and lactating cows was conducted at the time of collection. Presumptive identification of S. aureus on blood agar was based on observation of colony morphology, color, and presence or absence of a broad zone of incomplete hemolysis and a smaller zone of complete hemolysis at 48 h. Those without hemolysis were presumptively characterized as CNS. All isolates were further plated on mannitol salt agar and a coagulase test was performed. A positive for both of these tests together was deemed to be S. aureus. A selection of isolates was tested using API® Staph to biochemically confirm S. aureus identification. Data showed that 63.96% of isolates presumed to be CNS isolates were identified as S. aureus, 9.46% of isolates presumed to be CNS isolates were identified as coagulase-positive staphylococci (CPS) species (but not S. aureus), and 26.58% of samples that were presumed to be CNS isolates were identified correctly.

scholarly journals Finding of coagulase negative staphylococci in the herd with an increased number of somatic cells in milk and their antimicrobial susceptibility

2013 ◽  
Vol 67 (3-4) ◽  
pp. 175-185
Author(s):  
Vera Katic ◽  
Natasa Rajic-Savic
Keyword(s):  
Clavulanic Acid ◽  
Somatic Cells ◽  
Inhibition Zone ◽  
Subclinical Mastitis ◽  
Blood Agar ◽  
Penicillin G ◽  
Coagulase Negative Staphylococci ◽  
Milk Samples ◽  
Causative Agents ◽  
Amoxicillin Clavulanic Acid

Coagulase-negative staphylococci (CNS) are generally considered to be opportunistic pathogens. Controlling CNS mastitis is difficult because the epidemiology is not clear, and the CNS group consists of about 40 different Staphylococcus species. Therefore, the aim of this study was to determine the prevalence of coagulasenegative staphylococci in milk of the cows with subclinical mastitis, as well as to determine different CNS species isolated from quarter milk samples for their susceptibility to antimicrobials used commonly for mastitis therapy. On the farm where there was found an increase of somatic cells in bulk milk, 112 dairy cows were examined by mastitis test. From 52 udder quarters where mastitis test showed an increase of somatic cells, milk samples were taken for bacteriological examination. For isolating the causes of mastitis there was used blood agar. Identification of the causative agents of mastitis was carried out on the basis of colony appearance on blood agar and their physiological characteristics. Coagulasepositive staphylococci sensitivity which cause mastitis was tested by Kirby Bauer method. For susceptibility testing there were used commercially produced discs containing: 10 IU penicillin, amoxicillin/clavulanic acid (20 +10 ?g), cloxacillin 25 ?g, 30 ?g amoxicillin, cephalexin 30 ?g, ceftiofur 30 ?g, 15 ?g lincomycin, gentamicin and tetracycline 30 ?g. The sensitivity of microorganisms was evaluated on the basis of inhibition zone diameter recommended by the manufacturer and was labeled as sensitive (S) moderately sensitive (I) or resistant (R). Coagulase-negative staphylococci were isolated from 61.53% of samples from cows with subclinical mastitis, making them the most common cause of subclinical mastitis. The highest resistance of coagulase-negative staphylococci was found to penicillin G (58.33% of isolates). Full sensitivity of coagulase-negative staphylococci was found to amoxicillin / clavulanic acid (100% of isolates), a good sensitivity to ceftiofur (83.33% of isolates), cefalexin (70.83% of isolates) and ceftriaxone (41.66% of isolates).

scholarly journals CD137 Signaling is Critical in Fungal Clearance During Systemic Candida albicans Infection

2021 ◽  
Author(s):  
Vu Vi Giang Tran ◽  
Zen Na Nu Nguyen ◽  
Byungsuk Kwon
Keyword(s):  
Innate Immunity ◽  
Candida Albicans ◽  
Defense Mechanisms ◽  
Tumor Necrosis ◽  
Fungal Infections ◽  
Fungal Growth ◽  
Immunocompromised Patients ◽  
Agonistic Antibody ◽  
Innate Defense ◽  
Surface Receptor

Invasive fungal infections by Candida albicans frequently cause mortality in immunocompromised patients. Neutrophils are particularly important for fungal clearance at the early phase of infections, yet little has been known regarding which surface receptor controls neutrophil phagocytic activities during systemic C. albicans infection. CD137, which is encoded by Tnfrsf9, belongs to the tumor necrosis receptor superfamily and has been shown to regulate neutrophils in Gram-positive bacterial infection. Here, we used genetic and immunological tools to probe the involvement of CD137 signaling in innate defense mechanisms against systemic C. albicans infection. We first found that Tnfrsf9-/- mice were susceptible to C. albicans infection, whereas injection of anti-CD137 agonistic antibody protected the host from infection, suggesting that CD137 signaling is indispensable for innate immunity against C. albicans infection. Priming of isolated neutrophils with anti-CD137 antibody promoted their phagocytic and fungicidal activities through phospholipase C. In addition, injection of anti-CD137 antibody significantly augmented restriction of fungal growth in Tnfrsf9-/- mice that received WT neutrophils. In conclusion, our results demonstrate that CD137 signaling contributes to defense mechanisms against systemic C. albicans infection by promoting rapid fungal clearance whereby harmful immunopathology-induced tissue injuries are minimalized.

scholarly journals Denture Stomatitis: Report of a Case with Rarely Used Treatment Modality and Review of Literature

2020 ◽  
Vol 4 (5) ◽  
pp. 116-119
Author(s):  
Parul Uppal Malhotra ◽  
Neera Ohri ◽  
Yagyeshwar Malhotra ◽  
Anindita Mallik
Keyword(s):  
Candida Albicans ◽  
Candida Species ◽  
Fungal Infections ◽  
Bacterial Colonization ◽  
Oral Candidiasis ◽  
Clinical Signs ◽  
Fungal Growth ◽  
Dimorphic Fungus ◽  
Denture Stomatitis ◽  
Microbial Invasion

Candida albicans is the most common Candida species isolated from the oral cavity both in healthy and diseased. Candida albicans is a dimorphic fungus existing both in blastopore phase (yeast phase) and the hyphal or mycelial phase. Although these organisms typically colonize mucocutaneous surfaces, the latter can be portals of entry into deeper tissues when host defences are compromised. Denture stomatitis is a common form of oral candidiasis that manifests as a diffuse inflammation of the maxillary denture bearing areas & is associated with angular cheilitis. At least 70% of individuals with clinical signs of denture stomatitis exhibit fungal growth & these conditions most likely result from yeast colonization of the oral mucosa combined with Bacterial colonization. Candida species act as an endogenous infecting agent on tissue predisposed by chronic trauma to microbial invasion. At one time, oral fungal infections were rare findings in general dentist's office. They were more commonly seen in hospitalized and severely debilitated patients. However with enhanced medical and pharmaceutical technology, increasing numbers of ambulatory immunosuppressed individuals with oral fungal infections are seeking out general dentists for diagnosis and treatment of these lesions.

Analysis of Fungi on Coix (Coix lacryma-jobi) Seed and the Effect of Its Aqueous Extract on the Growth of Aspergillus flavus

2019 ◽  
Vol 82 (10) ◽  
pp. 1775-1782 ◽  
Author(s):  
XUEMEI LUO ◽  
HONGXIA LI ◽  
DAN JIANG ◽  
JIEQIN MENG ◽  
FAN ZHANG ◽  
...  
Keyword(s):  
Dna Barcoding ◽  
Aspergillus Flavus ◽  
Aqueous Extract ◽  
High Throughput Sequencing ◽  
Rhizopus Oryzae ◽  
Fungal Infections ◽  
Fungal Growth ◽  
Promoting Effect ◽  
Illumina Hiseq ◽  
Coix Seed

ABSTRACT Coix (Coix lacryma-jobi) seeds are susceptible to fungal infections, making their surface fungi complex and diverse. Some fungi can produce mycotoxins under suitable conditions, and fungal growth is closely related to the production of mycotoxins. In this study, the surface fungi of coix seed were identified by Illumina HiSeq high-throughput sequencing. Simultaneously, the fungi cultured by the plate method were identified by microscopy and DNA barcoding; finally, the species of fungi were identified accurately and reliably by combining three methods. The aqueous extract of coix seed was cocultured with Aspergillus flavus spores, and the relationship between the aqueous extract and the growth of A. flavus was studied with the dry weight of mycelium as an indicator. The results showed that there were 89 genera and 96 species of fungi on coix seed, which were mainly distributed in Ascomycota (81.48%) and Basidiomycota (4.08%), and Xeromyces (8.50%), Gibberella (7.25%), and Aspergillus (4.74%) were the predominant genera. Four fungi were isolated from coix seed by plate culture and identified as Aspergillus fumigatus, A. flavus, Aspergillus oryzae, and Rhizopus oryzae by microscopy and DNA barcoding. The aqueous extract of coix seed at low concentrations has a promoting effect on the growth of A. flavus. When the concentration is 3.125%, the promotion effect is the most pronounced, and the promotion rate is 29.17%. These results reveal the diversity of fungi on the coix seed, which can provide a reference for the prevention and control of harmful fungi on coix seed.

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