Microbial transmission
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V retrospektivní studii byly hodnoceny incidence, diagnostika, vyvolávající agens a výsledky terapie mikrobiálních zánětů očnice. Za období od 1. 1. 1997 do 31. 12. 1999 bylo hospitalizováno 66 dětí s diagnózou zánětu očnice. Průměrný věk v souboru byl 6,2 roku, průměrná délka hospitalizace 10,2 dne. Byla použita Chandlerova klasifikace zánětů očnice. Diagnóza byla stanovena za spolupráce oftalmologa, otolaryngologa a rentgenologa. Hlavní příčinou zánětů očnice byl zánět paranazálních dutin. Nejčastějšími mikrobiálními agens byly zjištěny streptokoky, stafylokoky a Haemophilus influenzae. Všichnipacienti byli léčeni zahospitalizace intravenózněpodávanýmiantibiotiky. Chirurgická léčba byla nutná v 8 případech – u 4 pacientů s orbitálním abscesem a u 4 pacientů se subperiostálním abscesem nereagujícím na konzervativní terapii. Chirurgický výkon byl proveden otolaryngologem výhradně za použití endonazálního přístupu. V našem souboru jsme nezaznamenali žádné trvalé oční komplikace jako následek zánětu očnice.
The author evaluates in a retrospective study the incidence, diagnosis and causal agent and therapeutic results of microbial inflammations of the orbit. During the period from Jan.1 1997 till Dec.31 1999 66 children were hospitalized with the diagnosis of inflammation of the orbit. The mean age of the children was 6.2 years, the mean period of hospitalization 10.2 days. Chandler´s classification of inflammations of the orbit was used. The diagnosis was established in collaboration by an ophthalmologist, otolyryngologist and roentgenologist. The main cause of inflammations of the orbit was inflammation of the paranasal sinuses. The most frequent microbial agents were streptococci, staphylococci and Haemophilus influenzae. All patients were treated during hospitalization by antibiotics administered by the i.v. route. Surgery was necessary in 8 patients - in 4 patients with an orbital abscess and in 4 patients with a subperiostal abscess not responding to conservative treatment. The operation was performed by an otolaryngologist using always the endonasal approach. The authors did not record in their group any permanent ophthalmological complications resulting from the inflammation of the orbit.
- MeSH
- absces diagnóza chirurgie mikrobiologie MeSH
- antibakteriální látky terapeutické užití MeSH
- dítě MeSH
- lidé MeSH
- mikrobiologické techniky MeSH
- nemoci orbity diagnóza mikrobiologie terapie MeSH
- počítačová rentgenová tomografie MeSH
- retrospektivní studie MeSH
- zánět diagnóza klasifikace terapie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- Publikační typ
- přehledy MeSH
Quantitation of viruses is practised widely in both basic and applied virology. Infectious titration in cell cultures, the most common approach to it, is quite labour-intensive and alternative protocols are therefore sought. One of the alternatives is transmission electron microscope (TEM) quantitation using latex particles at a known concentration as a reference for counting virus particles. If virus TCID₅₀ is determined in parallel, the ratio of infectious to non-infectious virus particles may be established. This study employs such an approach to compute the number of virus particles and TCID₅₀, and establish their correlation for three viruses: Canine adenovirus 1 (CAdV-1), Feline calicivirus (FCV) and Bovine herpesvirus 1 (BoHV-1). Each of the viruses was grown in five replicates until complete cytopathology was recorded (time 0), then frozen. They were thawed, filter-sterilised and left for additional periods of 16, 32 and 48 h at 37°C. At each time point, the infectious ability of the virus was characterised by TCID50 and the number of virions quantified by TEM, in order to evaluate the influence of timing on virus harvest. The virus particle count determined by TEM did not change for any of the viruses throughout the experiment. The relationship between virus particle counts with TCID₅₀ at time 0 showed good linearity response; their ratio was almost constant. The virus particle-to-TCID₅₀ ratio varied between 146 and 426 (mean±SD: 282±103) for CAdV-1, between 36 and 79 (57±18) for FCV and between 110 and 249 (167±53) for BoHV-1. The proportion of non-infectious particles did not change throughout the experiment for either CAdV-1 or BoHV-1. However, a decrease in virus infectious ability disclosed by TCID₅₀ indicated that the fraction of non-infectious particles in FCV increased 300,000 times when time 0 and 48 h were compared. The quantitation of viruses with TEM is a simple and rapid protocol for virus quantitation but account must be taken of the type of virus and harvesting time as virus counts need not necessarily correlate with virus infectious ability.
- MeSH
- bovinní herpesvirus 1 izolace a purifikace fyziologie MeSH
- buněčné linie MeSH
- časové faktory MeSH
- kočičí kalicivirus izolace a purifikace fyziologie MeSH
- kultivace virů MeSH
- mikrobiální viabilita * MeSH
- psí adenoviry izolace a purifikace fyziologie MeSH
- transmisní elektronová mikroskopie metody MeSH
- virová nálož metody MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Antibiotická rezistence dnes představuje globální problém zdravotnictví. Nejenže se zvyšuje incidence onemocnění vyvolaných rezistentními patogenními kmeny bakterií, ale také neúměrně stoupají náklady na léčbu, prodlužuje se doba hospitalizace a nezřídka narůstá i úmrtnost. Proto je třeba při indikaci antibiotické terapie mít stále na paměti, že nadužívání, či zneužívání antibiotik přispívá k šíření genů, jež antibiotickou rezistenci kódují. Stejně tak to platí pro aplikace antibiotik ve veterinární medicíně, zemědělství včetně akvakultur nebo v potravinářském průmyslu. Genetická informace se zejména u prokaryot přenáší také horizontálně (laterálně), přímou výměnou genetického materiálu přes druhové bariéry. U nich je výměna genů nebo celých genových úseků horizontálním přenosem zcela běžná. Mohou tak dynamicky a v relativně krátkém čase vznikat vysoce rozmanité genomy, což vertikální přenos neumožňuje. Díky tomu mohou prokaryota rychle nabývat nové vlastnosti včetně virulence a patogenity, a také rezistence na toxiny včetně antibiotik, které zvyšují jejich adaptabilitu. Proto jsou reinfekce rezistentními mikroorganismy vždy obtížněji léčitelné než infekce vyvolané nerezistentními bakteriemi.
Antibiotic resistance today is a global problem of health care service. Not only does the number of diseases caused by resistant pathogenic strains of bacteria increase, but also the cost of treatment increases disproportionately, the length of hospitalization is prolonged, and mortality is often rising. Therefore, when indicating antibiotic therapy, it is important to keep in mind that both overuse and abuse of antibiotics contribute to the spread of antibiotic resistance genes. This is equally true for antibiotic applications in veterinary medicine, agriculture, including aquacultures, or in the food industry. Genetic information is in prokaryotes transmitted as well horizontally (laterally), by direct exchange of genetic material across species barriers in which the exchange of genes or whole gene segments by horizontal transmission is quite common. They can dynamically and in a relatively short time generate highly diverse genomes, which does not allow the vertical transmission. As a result, prokaryotes can rapidly acquire new properties such as virulence and pathogenicity, as well as resistance to toxins, including antibiotics, by which they increase their adaptability. Therefore, reinfection-resistant microorganisms are always more difficult to treat than infections caused by non-resistant bacteria.
Antibiotics are the most efficient type of therapy developed in the twentieth century. From the early 1960s to the present, the rate of discovery of new and therapeutically useful classes of antibiotics has significantly decreased. As a result of antibiotic use, novel strains emerge that limit the efficiency of therapies in patients, resulting in serious consequences such as morbidity or mortality, as well as clinical difficulties. Antibiotic resistance has created major concern and has a greater impact on global health. Horizontal and vertical gene transfers are two mechanisms involved in the spread of antibiotic resistance genes (ARGs) through environmental sources such as wastewater treatment plants, agriculture, soil, manure, and hospital-associated area discharges. Mobile genetic elements have an important part in microbe selection pressure and in spreading their genes into new microbial communities; additionally, it establishes a loop between the environment, animals, and humans. This review contains antibiotics and their resistance mechanisms, diffusion of ARGs, prevention of ARG transmission, tactics involved in microbiome identification, and therapies that aid to minimize infection, which are explored further below. The emergence of ARGs and antibiotic-resistant bacteria (ARB) is an unavoidable threat to global health. The discovery of novel antimicrobial agents derived from natural products shifts the focus from chemical modification of existing antibiotic chemical composition. In the future, metagenomic research could aid in the identification of antimicrobial resistance genes in the environment. Novel therapeutics may reduce infection and the transmission of ARGs.
Acanthamoeba is known to interact with a plethora of microorganisms such as bacteria, fungi and viruses. In these interactions, the amoebae can be predatory in nature, transmission vehicle or an incubator. Amoebae consume microorganisms, especially bacteria, as food source to fulfil their nutritional needs by taking up bacteria through phagocytosis and lysing them in phagolysosomes and hence play an eminent role in the regulation of bacterial density in the nature and accountable for eradication of around 60% of the bacterial population in the environment. Acanthamoeba can also act as a "Trojan horse" for microbial transmission in the environment. Additionally, Acanthamoeba may serve as an incubator-like reservoir for microorganisms, including those that are pathogenic to humans, where the microorganisms use amoebae's defences to resist harsh environment and evade host defences and drugs, whilst growing in numbers inside the amoebae. Furthermore, amoebae can also be used as a "genetic melting pot" where exchange of genes as well as adaptation of microorganisms, leading to higher pathogenicity, may arise. Here, we describe bacteria, fungi and viruses that are known to interact with Acanthamoeba spp.
Ixodes ricinus tick saliva-activated transmission of Borrelia burgdorferi sensu stricto spirochetes was studied on the C3H/HeN mouse model. The influence of the feeding of uninfected nymphs on the proliferation and distribution of intradermally inoculated spirochetes was compared with the effect of co-inoculated saliva or salivary gland extract (SGE), respectively. Spirochete loads in murine tissues were evaluated using real-time q-PCR. SGE induced significantly increased spirochete numbers in the skin on the days 4 and 6 post-infection (p.i.). On the other hand, decreased bacterial load in the heart of SGE-treated mice was demonstrated in comparison with control animals. The inoculation of tick saliva increased spirochete load in the urinary bladder on day 6 p.i., while the number of spirochetes in the heart declined on day 6 p.i. The feeding of I. ricinus nymphs raised the spirochete load in the bladder on the days 4 and 6 p.i. On day 6, the number of spirochetes found in the heart was significantly lower than in controls. The prevalence of spirochetes in ticks infected by feeding on mice was more than 10 times higher when the mice were infected with the mixture of spirochetes and saliva or SGE, in comparison with spirochetes alone. The presence of SGE in the infectious inoculum increased the spirochete burden per tick from 0 to almost 28,000. Taken together, these results show a very early effect of tick saliva on the proliferation and distribution of Borrelia spirochetes in the host, probably due to the effect of saliva on the host innate immunity mechanisms.
- MeSH
- Borrelia burgdorferi růst a vývoj MeSH
- klíště mikrobiologie MeSH
- kůže mikrobiologie MeSH
- lymeská nemoc mikrobiologie přenos veterinární MeSH
- močový měchýř mikrobiologie MeSH
- myši inbrední C3H MeSH
- myši MeSH
- počet mikrobiálních kolonií MeSH
- sliny mikrobiologie MeSH
- srdce mikrobiologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
OBJECTIVE: Water-pipe smoking has become a serious public health threat worldwide. In order to raise awareness of adverse effects and transmission of bacteria via water-pipe smoking, we aimed to identify the bacteria and their antimicrobial resistance profiles that colonize different parts of waterpipes. METHODS: We examined totally 182 water pipes from 7 lounges (in Turkey) used in public places and we collected 728 culture samples in total by microbiological methods. We used disposable sterile swabs to sample the inside and outside of the mouthpiece, and the handling piece and sterile injectors were used to collect 5 mL of water from the water pipe bowl. RESULTS: There was a significant (p < 0.05) difference in microbial contamination (growth/presence of bacteria and fungi) among the parts of the water pipes sampled. There was a significant (p < 0.05) difference in the number of bacteria growing (microbial load) among the parts of the water pipes. Only one narghile lounge out of seven, which had 13 water pipes, had a hygiene procedure. The water jars are often contaminated with Gram-negative bacteria. CONCLUSION: Water pipes, especially the interior and outer part of the mouthpieces and the handle, are colonized by microbes and pose a risk of infection. Procedures for water pipe hygiene should be developed, periods should be defined, and the owners and employees of establishments and water-pipe smokers should be educated in this regard. Water-pipe smoking is a threat to public health and should be regulated by the state.
- MeSH
- hodnocení rizik MeSH
- infekce epidemiologie MeSH
- kouření vodní dýmky škodlivé účinky MeSH
- lidé MeSH
- vodní dýmky mikrobiologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Turecko MeSH
PURPOSE: Contact lenses can be contaminated with various microorganisms, including pathogenic yeasts of the genus Candida, which are known for their ability to adhere to abiotic surfaces, including plastic materials used for various medical purposes. Microbial contamination of the lenses can lead to infection of the wearer's eyes. The purpose of this study was to simulate the contamination of contact lenses with C. albicans and C. parapsilosis, analyze the interaction of the microorganisms with the lens material, and optimize the protocol for PCR-based analysis of the microbial agents responsible for lens contamination. METHODS: Hilafilcon lenses were exposed to C. albicans and C. parapsilosis cultures, washed, and examined for their ability to further spread the contamination. Scanning electron microscopy was used to analyze the attachment of yeast cells to the lenses. Infrared spectroscopy was used to examine the potential changes in the lens material due to Candida contamination. The protocol for DNA isolation from contaminated lenses was established to enable PCR analysis of microbes attached to the lenses. RESULTS: Hilafilcon lenses contaminated with Candida were able to spread the contamination even after washing with saline or with a commercial cleaning solution. In the present experimental settings, the yeasts did not grow into the lenses but began to form biofilms on the surface. However, the ability of the lenses to retain water was altered. The PCR-based protocol could be used to help identify the type of contamination of contact lenses. CONCLUSION: Once contaminated with Candida albicans or Candida parapsilosis, Hilafilcon contact lenses are difficult to clean. Yeasts began to form biofilms on lens surfaces.
- MeSH
- biofilmy MeSH
- Candida albicans izolace a purifikace fyziologie MeSH
- Candida izolace a purifikace fyziologie MeSH
- kandidóza * mikrobiologie MeSH
- kontaktní čočky mikrobiologie MeSH
- kontaminace zdravotnického vybavení * MeSH
- lidé MeSH
- měkké kontaktní čočky mikrobiologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Topical microbicides to stop sexually transmitted diseases, such as herpes simplex virus type 2 (HSV-2), are urgently needed. The emerging field of nanotechnology offers novel suitable tools for addressing this challenge. Our objective was to study, in vitro and in vivo, antiherpetic effect and antiviral mechanisms of several polyanionic carbosilane dendrimers with anti-HIV-1 activity to establish new potential microbicide candidates against sexually transmitted diseases. Plaque reduction assay on Vero cells proved that G2-S16, G1-S4, and G3-S16 are the dendrimers with the highest inhibitory response against HSV-2 infection. We also demonstrated that our dendrimers inhibit viral infection at the first steps of HSV-2 lifecycle: binding/entry-mediated events. G1-S4 and G3-S16 bind directly on the HSV-2, inactivating it, whereas G2-S16 adheres to host cell-surface proteins. Molecular modeling showed that G1-S4 binds better at binding sites on gB surface than G2-S16. Significantly better binding properties of G1-S4 than G2-S16 were found in an important position for affecting transition of gB trimer from G1-S4 prefusion to final postfusion state and in several positions where G1-S4 could interfere with gB/gH-gL interaction. We demonstrated that these polyanionic carbosilan dendrimers have a synergistic activity with acyclovir and tenofovir against HSV-2, in vitro. Topical vaginal or rectal administration of G1-S4 or G2-S16 prevents HSV-2 transmission in BALB/c mice in values close to 100%. This research represents the first demonstration that transmission of HSV-2 can be blocked by vaginal/rectal application of G1-S4 or G2-S16, providing a step forward to prevent HSV-2 transmission in humans.
- MeSH
- acyklovir farmakologie MeSH
- antiinfekční látky farmakologie MeSH
- antivirové látky farmakologie MeSH
- aplikace rektální MeSH
- Cercopithecus aethiops MeSH
- dendrimery chemie MeSH
- epitelové buňky účinky léků virologie MeSH
- herpes simplex MeSH
- koncentrace vodíkových iontů MeSH
- lidé MeSH
- lidský herpesvirus 2 účinky léků MeSH
- molekulární modely MeSH
- myši inbrední BALB C MeSH
- polymery chemie MeSH
- rektum účinky léků virologie MeSH
- silany chemie MeSH
- tenofovir farmakologie MeSH
- vagina účinky léků virologie MeSH
- Vero buňky MeSH
- virové proteiny metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Background: Controlling hepatitis C virus (HCV) transmission among people who inject drugs (PWID) has focused on preventing sharing syringes and drug preparation paraphernalia, but it is unclear whether HCV incidence linked to sharing paraphernalia reflects contamination of the paraphernalia or syringe-mediated contamination when drugs are shared. Methods: In experiments designed to replicate real-world injection practices when drugs are shared, the residual contents of HCV-contaminated syringes with detachable or fixed needled were passed through the "cookers" and filters used by PWID in preparing drugs for injection and then introduced into a second syringe. All items were tested for the presence of infectious HCV using a chimeric HCV with a luciferase gene. Results: Hepatitis C virus could not be recovered from cookers regardless of input syringe type or cooker design. Recovery was higher when comparing detachable needles to fixed needles for residue in input syringes (73.8% vs 0%), filters (15.4% vs 1.4%), and receptive syringes (93.8% vs 45.7%). Conclusions: Our results, consistent with the hypothesis that sharing paraphernalia does not directly result in HCV transmission but is a surrogate for transmissions resulting from sharing drugs, have important implications for HCV prevention efforts and programs that provide education and safe injection supplies for PWID populations.
- MeSH
- Hepacivirus izolace a purifikace fyziologie MeSH
- hepatitida C přenos MeSH
- injekční stříkačky virologie MeSH
- intravenózní abúzus drog komplikace MeSH
- lidé MeSH
- mikrobiální viabilita * MeSH
- mikrobiologie životního prostředí * MeSH
- přenos infekční nemoci MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Research Support, N.I.H., Extramural MeSH
