Biofilms are increasingly implicated as playing a major role in waterborne cryptosporidiosis. This review aims to synthesize all currently available data on interactions between
oocysts and biofilms. ...Initially described following a waterborne outbreak, the integration of
oocysts in biofilm has been well demonstrated. Biofilms appear important in the dissemination/protection of oocysts in the environment. Consequently, it has been suggested that substrate-associated biofilms should be systematically considered in oocyst water quality assessment. The influence of physicochemical parameters has been studied on oocyst biofilm retention. Biofilm surface roughness, ionic concentration (especially Ca
), laminar/turbulent flow, shear stress, and electrostatic repulsion forces appear important to consider regarding oocyst release from biofilm. However, data analysis carried out during this review also revealed important gaps in biological interactions within biofilms, offering many perspectives for future work.
Cryptosporidium sp. are common intracellular parasites responsible of severe diarrhea in T-cell-immunocompromised patients. We report the first case of a woman who contracted cryptosporidiosis after ...treatment with fingolimod, a drug labeled for multiple sclerosis and responsible for marked lymphopenia.
A 60-year-old woman was admitted for abdominal pain diarrhea and fever. The patient suffered from multiple sclerosis and had been treated with fingolimod from august 2017 to september 2018 time of occurrence of the first digestive symptoms. Stool culture was negative but parasitological examination was positive for Cryptosporidium sp. Blood biological examination profound lymphopenia of 240/mm
17 CD4/mm
(7%) and 32 CD8/mm
(14%). Fingolimod was stopped, and the patient was put on nitazoxanide 500 mg bid for 7 days. The diarrhea resolved and no relapse was observed. Six other cases were found in the Pharmacovigilance database.
Physicians should be aware of this association and screen for Cryptosporidium in cases of diarrhea in patients treated with fingolimod. Patients should be aware of this risk and advise to take appropriate measures to avoid such contamination.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To determine the Etest-based epidemiological cut-off values (ECVs) for antifungal agents against the most frequent yeast and Aspergillus fumigatus species isolated in 12 French hospitals.
For each ...antifungal agent, the Etest MICs in yeast and A. fumigatus isolates from 12 French laboratories were retrospectively collected from 2004 to 2018. The ECVs were then calculated using the iterative statistical method with a 97.5% cut-off.
Forty-eight Etest ECVs were determined for amphotericin B, caspofungin, micafungin, anidulafungin, fluconazole, voriconazole, posaconazole and itraconazole, after pooling and analysing the MICs of 9654 Candida albicans, 2939 Candida glabrata SC, 1458 Candida parapsilosis SC, 1148 Candida tropicalis, 575 Candida krusei, 518 Candida kefyr, 241 Candida lusitaniae, 131 Candida guilliermondii and 1526 Aspergillus fumigatus species complex isolates. These ECVs were 100% concordant (identical or within one two-fold dilution) with the previously reported Etest-based ECVs (when available), and they were concordant in 76.1% of cases with the Clinical and Laboratory Standards Institute ECVs and in 81.6% of cases with the European Committee on Antimicrobial Susceptibility Testing ECVs.
On the basis of these and other previous results, we recommend the determination of method-dependent ECVs. Etest ECVs should not be used instead of breakpoints, but may be useful to identify non-wild-type isolates with potential resistance to antifungal agents, and to indicate that an isolate may not respond as expected to the standard treatment.
Aims
The study was aimed to understand the depuration process of Cryptosporidium parvum and Toxoplasma gondii oocysts by zebra mussel (Dreissena polymorpha), to consider the use of the zebra mussel ...as a bioremediation tool.
Materials and methods
Two experiments were performed: (i) individual exposure of mussel to investigate oocyst transfers between bivalves and water and (ii) in vivo exposure to assess the ability of the zebra mussel to degrade oocysts.
Results
(i) Our results highlighted a transfer of oocysts from the mussels to the water after 3 and 7 days of depuration; however, some oocysts were still bioaccumulated in mussel tissue. (ii) Between 7 days of exposure at 1000 or 10 000 oocysts/mussel/day and 7 days of depuration, the number of bioaccumulated oocysts did not vary but the number of infectious oocysts decreased.
Conclusion
Results show that D. polymorpha can release oocysts in water via (pseudo)faeces in depuration period. Oocysts remain bioaccumulated and infectious oocyst number decreases during the depuration period in zebra mussel tissues. Results suggest a degradation of bioaccumulated C. parvum and T. gondii oocysts.
Significance and Impact of the Study
This study highlighted the potential use of D. polymorpha as a bioremediation tool to mitigate of protozoan contamination in water resources.
Cryptosporidium spp., a significant cause of foodborne infection, have been shown to be resistant to most chemical food disinfectant agents and infective for weeks in irrigation waters and stored ...fresh vegetal produce. Pulsed UV light (PL) has the potential to inactivate Cryptosporidium spp. on surfaces of raw or minimally processed foods or both. The present study aimed to evaluate the efficacy of PL on viability and in vivo infectivity of Cryptosporidium parvum oocysts present on raspberries, a known source of transmission to humans of oocyst-forming apicomplexan pathogens. The skin of each of 20 raspberries was experimentally inoculated with five 10-μl spots of an oocyst suspension containing 6 × 10(7) oocysts per ml (Nouzilly isolate). Raspberries were irradiated by PL flashes (4 J/cm(2) of total fluence). This dose did not affect colorimetric or organoleptic characteristics of fruits. After immunomagnetic separation from raspberries, oocysts were bleached and administered orally to neonatal suckling mice. Seven days after infection, mice were euthanized, and the number of oocysts in the entire small intestine was individually assessed by immunofluorescence flow cytometry. Three of 12 and 12 of 12 inoculated mice that received 10 and 100 oocysts isolated from nonirradiated raspberries, respectively, were found infected. Four of 12 and 2 of 12 inoculated mice that received 10(3) and 10(4) oocysts from irradiated raspberries, respectively, were found infected. Oocyst counts were lower in animals inoculated with 10(3) and 10(4) oocysts from irradiated raspberries (92 ± 144 and 38 ± 82, respectively) than in animals infected with 100 oocysts from nonirradiated raspberries (35,785 ± 66,221, P = 0.008). PL irradiation achieved oocyst reductions of 2 and 3 log for an inoculum of 10(3) and 10(4) oocysts, respectively. The present pilot-scale evaluation suggests that PL is an effective mode of decontamination for raspberries and prompts further applicability studies in industrial contexts.
Quenching-time characterization is the way to measure the speed of chalcogenide material to transform from the amorphous (RESET) state to the crystalline (SET) one after application of a proper ...programming pulse. It is here proposed to study the impact of process and programming conditions on cell performances, highlighting possible composition variation, and modifications of the physical dimension of the PCM active volume (the dome).
A new challenge for semiconductor industry is to reach low permittivity (
k
<
2.4) required for advanced microelectronic interconnections. Porosity introduction in SiOCH matrix is the main research ...field investigated. Several synthesis ways can be used to deposit these nanoporous SiOCH layers. In this work, plasma enhanced chemical vapor deposition (PECVD) of this material using three different concepts (porogen approach, cyclic precursor, foaming) is studied and compared to spin-coated films. It is shown that the porogen approach, which consists in the co-deposition of a matrix precursor and a sacrificial organic porogen followed by a post-treatment to remove the organic porogen phase, allows to create porosity in a thin SiOCH film. The impact of deposition process and curing on basic film properties such as dielectric constant, porosity and elastic properties are studied. Foaming appears as another attractive way to deposit nanoporous SiOCH using PECVD.
La prévalence de la leishmaniose cutanée a augmenté durant les dix dernières années, et en particulier chez les sujets immunodéprimés vivant en zones d'endémie.
Nous rapportons l'observation ...originale d'une patiente, atteinte de polymyosite corticorésistante, ayant présenté une leishmaniose cutanée dont l'évolution était favorable après instauration d'un traitement par Glucantime
® par voie intralésionnelle.
La leishmaniose cutanée est une infection opportuniste. De fait, elle est 100 fois plus fréquente chez les sujets immunodéprimés, le plus souvent infectés par le VIH. Chez notre patiente, les facteurs ayant favorisé l'immunodépression étaient la polymyosite et la corticothérapie ; la prednisone pourrait induire des perturbations de l'immunité cellulaire, comme en témoigne la mise en évidence, chez les patients traités, d'une réduction significative des taux de lymphocytes T (CD4 et CD8) et de cytokines synthétisées par ces lymphocytes T (notamment l'interféron gamma).
The prevalence of cutaneous leishmaniasis is increasing, especially in immunocompromized subjects.
We report a case of particular interest, where a patient with steroid refractory polymyositis developed cutaneous leishmaniasis. Clinical outcome was favorable after institution of intralesional antimony therapy.
Cutaneous leishmaniasis is still recognized to be an opportunistic infection. Its frequency is indeed higher in immunocompromized subjects, mainly HIV-infected patients. In our patient, both polymyositis and steroid therapy were predisposing factors of cutaneous leishmaniasis onset; prednisone therapy has been postulated to be associated with immune dysfunction leading to: reduced blood T cells' levels (CD4 et CD8) as well as decreased cytokine synthesis (e.g. interferon gamma).
Toxoplasma gondii
,
Cryptosporidium parvum
, and
Giardia duodenalis
are human waterborne protozoa. These worldwide parasites had been detected in various watercourses as recreational, surface, ...drinking, river, and seawater. As of today, water protozoa detection was based on large water filtration and on sample concentration. Another tool like aquatic invertebrate parasitism could be used for sanitary and environmental biomonitoring. In fact, organisms like filter feeders could already filtrate and concentrate protozoa directly in their tissues in proportion to ambient concentration. So molluscan shellfish can be used as a bioindicator of protozoa contamination level in a site since they were sedentary. Nevertheless, only a few researches had focused on nonspecific parasitism like protozoa infection on aquatic invertebrates. Objectives of this review are twofold: Firstly, an overview of protozoa in worldwide water was presented. Secondly, current knowledge of protozoa parasitism on aquatic invertebrates was detailed and the lack of data of their biological impact was pointed out.
Cryptosporidiosis is an important though underreported public health concern. Molecular tools might be helpful in improving its diagnosis. In this study, ZR Fecal DNA MiniPrep™ Kit (ZR) and ...NucliSens® easyMAG® (EM) were compared using four
Cryptosporidium
-seeded feces and 29
Cryptosporidium
-positive stools. Thereafter, ZR was selected for prospective evaluation of
Cryptosporidium
detection by 18S rDNA and LAXER quantitative PCR (qPCR) in 69 stools from 56 patients after
Cryptosporidium
detection by glycerin, modified Ziehl–Neelsen (ZN) and auramine–phenol (AP) stainings. The combination of any of the two extraction methods with 18S qPCR yielded adequate detection of
Cryptosporidium
in seeded stools, but the ZR kit showed the best performance. All 29
Cryptosporidium
-positive samples were positive with 18S qPCR, after both ZR and EM extraction. However, false-negative results were found with LAXER qPCR or nested PCR. Cryptosporidiosis was diagnosed in 7/56 patients. All the microscopic methods enabled the initial diagnosis, but
Cryptosporidium
was detected in 12, 13, and 14 samples from these seven patients after glycerin, ZN, and AP staining respectively. Among these samples, 14 and 12 were positive with 18S and LAXER qPCR respectively. In two patients,
Cryptosporidium
DNA loads were found to be correlated with clinical evolution. Although little known, glycerin is a sensitive method for the initial detection of
Cryptosporidium
. When combined with 18S qPCR, ZR extraction, which had not been evaluated so far for
Cryptosporidium
, was an accurate tool for detecting
Cryptosporidium
and estimating the oocyst shedding in the course of infection.
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