Candida Biofilms: Environmental and Clinical Aspects

Candida spp. strains are characterized by their ability to form a biofilm structure on biotic and abiotic surfaces, causing significant problems in many industrial branches and threatening human health. Candida biofilm is a heterogeneous, spatially well-organized structure consisting of planktonic and mycelial yeast forms which are interdependent in the quorum sensing system and surrounded by an extracellular polysaccharide substance. Biofilm-forming microorganisms are characterized by high invasiveness, the ability to cause dangerous and difficult to treat infections. Furthermore, the cells in the biofilm, compared to planktonic forms, show reduced sensitivity to chemical compounds with antifungal activity and increased survival under unfavorable environmental conditions. The chapter focuses on the emergence of antifungal resistance with the development of biofilms. The work presents the examples of antibiotic resistance of a variety of Candida, showing that a group of strains expressing intermediate sensitivity or resistance to the tested antibiotics include both clinical and food-borne isolates. Similarities in enzymatic and biochemical profiles of different origin isolates are discussed. A substantial heterogeneity within Candida albicans group is also underlined. Simultaneously, the incidents of biochemical profiles conformity of some clinical and food-borne isolates are presented, which may be a result of Candida transmission via food

The effect of thyme and tea tree oils on morphology and metabolism of Candida albicans

Members of Candida species cause significant problems in medicine and in many industrial branches also. In order to prevent from Candida sp. development, essential oils are more and more frequently applied as natural, non-toxic, non-pollutive and biodegradable agents with a broad spectrum of antimicrobial activity. The aim of the research was to determine changes in morphology and metabolic properties of Candida albicans in the presence of thyme and tea tree oils. Changes of enzymatic activity of isolates were observed in the presence of both tested essential oils, and they were primarily associated with loss or decrease of activity of all enzymes detected for control. Furthermore, only for 3 out of 11 isolates additional activity of N-acetyl-β-glucosaminidase, α-mannosidase, α-fucosidase and trypsin was detected. Vivid changes in biochemical profiles were found after treatment with tea tree oil and they were related to loss of ability to assimilate d-xylose, d-sorbitol and d-trehalose. The main differences in morphology of isolates compared to the control strain concerned formation of pseudohyphae structures. Both examined essential oils caused changes in cell and colony morphology, as well as in the metabolism of Candida albicans. However, the extent of differences depends on the type and concentration of an essential oil. The most important finding is the broad spectrum of changes in yeast enzymatic profiles induced by thyme and tea tree oils. It can be supposed that these changes, together with loss of ability to assimilate saccharides could significantly impact Candida albicans pathogenicity

Predicting the conversion of mild cognitive impairment to Alzheimer's disease based on the volumetric measurements of the selected brain structures in magnetic resonance imaging

Introduction Mild cognitive impairment (MCI) is defined as abnormal cognitive state, but does not meet the criteria for the diagnosis of dementia. According to the new guidelines Alzheimer's disease (AD) involves not only dementia's phase but also predementia phase which is asymptomatic and pathological process in the brain is already present. For this reason it is very important to determine the suitability of markers which should be positive before onset of the first symptoms. One of these biomarkers is a structural magnetic resonance imaging with hippocampal volumetric assessment. The aim of this study was to investigate the usefulness of structural brain magnetic resonance imaging with volumetric assessment of the hippocampus and entorhinal cortex, posterior cingulate gyrus, parahippocampal gyrus, temporal gyri: superior, medial and inferior, to predict the conversion of MCI to AD. Material and methods Magnetic resonance imaging of brain was performed at the baseline visit in 101 patients diagnosed with MCI. Clinic follow-ups were scheduled after 6.12 and 24 months. Results Amongst 101 patients with MCI, 17 (16.8%) converted into AD within two years of observation. All measured volumes were lower in converters than non-converters. Discriminant analysis was conducted and sensitivity for MCI conversion to AD was 64.7%, specificity 96.4%. 91% of patients were correctly classified (converter or non-converter). Conclusions Volumetric measurements may help clinicians to predict MCI conversion to AD but due to low sensitivity it cannot be use separately. The study group requires further observation

The retinoids - drug with broad opportunities for use in dermatological diseases

Przedmiotem pracy jest obszerna grupa leków jaką stanowią retinoidy i ich wykorzystanie w leczeniu wielu różnorodnych schorzeń dermatologicznych. Są to pochodne witaminy A, na których budowę składa się pierścień β-jononu i łańcuchy izoprenoidowe. Do tej grupy substancji należą: retinol, retinal i kwas retinowy oraz ich dalsze metabolity i izomery.W organizmie człowieka retinoidy spełniają wiele ważnych funkcji. Głównym ich zadaniem jest udział w procesie widzenia oraz rozwoju płodu. Z punktu widzenia dermatologii bardzo ważnym zadaniem jest wpływ na różnicowanie i proliferację komórek nabłonka oraz normalizacja procesów złuszczania naskórka. W pracy omówiono choroby skóry, w których terapii wykorzystywane są retinoidy. Przedstawiono krótki opis schorzeń oraz dawkowanie, stosowanie i przybliżony czas leczenia pochodnymi witaminy A. W literaturze naukowej najobszerniej opisana jest terapia trądziku pospolitego z zastosowaniem retinoidów. Leki te regulują procesy rogowacenia i normalizują wydzielanie łoju, dzięki czemu udrażniają ujścia gruczołów łojowych i zapobiegają ich zaczopowaniu, a w konsekwencji hamują powstawanie wykwitów trądzikowych. Wpływając na przemiany kwasu arachidonowego, zależne od lipooksygenazy, zmniejszają powstawanie stanów zapalnych. Dzięki temu ograniczają one powstawanie rumienia, występowanie grudek i krost oraz redukują już powstałe teleangiektazje. Właściwości te czynią je bardzo przydatnymi lekami w terapii trądziku różowatego, jednak do tej pory nie posiadają one rejestracji do stosowania w tym schorzeniu i terapia nimi jest „off-label”. Dzięki swojemu wpływowi na funkcjonowanie układu odpornościowego, regulacji działania komórek Langerhansa w skórze oraz hamowaniu czynników chemotaktycznych, pochodne witaminy A są najczęściej i z wielkim powodzeniem stosowane także w terapii łuszczycy. Choroby autoimmunologiczne stanowią duży problem w dzisiejszych czasach. W terapii schorzeń takich jak toczeń rumieniowaty znalazły zastosowanie retinoidy pochodzące z różnych generacji m.in. izotretynoina, alitretynoina oraz acytretyna. Wpływ retinoidów na proliferację i różnicowanie komórek naskórka, hamowanie nadmiernego złuszczania lub normalizacja rogowacenia, w przypadku gdy zachodzi ono zbyt wolno pozwala na leczenie wielu chorób grudkowo – złuszczających takich jak liszaj płaski czy czerwony łupież mieszkowy oraz wielu schorzeń z zaburzeniami procesu złuszczania komórek naskórka. Do takich schorzeń zalicza się różnego rodzaju genodermatozy takie jak choroba Dariera, rybia łuska oraz skóra pergaminowa.Szerokie spektrum działania pochodnych witaminy A pozwala również na skuteczną terapię zmian skórnych wywodzących się z chorób wirusowych. Dzięki wpływowi na procesy keratynizacji retinoidy mogą być stosowane w leczeniu brodawek płaskich oraz mięczaka zakaźnego. Ze względu na wiele działań niepożądanych nie powinny być jednak wykorzystywane jako leki I rzutu. Badania kliniczne przeprowadzone na przestrzeni ostatnich lat potwierdziły skuteczność retinoidów w zapobieganiu, powstawaniu i leczeniu stanów przednowotworowych oraz nowotworów szczególnie skóry. Przeprowadzanych jest wiele nowych badań klinicznych, które mają na celu sprawdzenie skuteczności tych leków w leczeniu nowotworów o różnej etiologii. Retinoidy znajdują zastosowanie w preparatach kosmetycznych. Szczególnie polecane są do pielęgnacji skóry dojrzałej, z objawami starzenia. Wpływają na produkcję kolagenu i proliferację fibroblastów, dzięki czemu skóra staję się lepiej uwodniona i zregenerowana. Odbijają promieniowanie UV, a co za tym idzie mają działanie fotoprotekcyjne. Stosując leki zawierające pochodne witaminy A należy pamiętać o wielu działaniach niepożądanych towarzyszących tym substancjom. Do najważniejszych z nich należy działanie teratogenne, dlatego należy zachować szczególną ostrożność oraz przed zastosowaniem retinoidów skonsultować się z lekarzem w sprawie skutecznych metod antykoncepcyjnych w trakcie i po zakończeniu terapii.The topic of this dissertation paper is vast group of retinoid medications and their application in the treatment of various dermatological diseases. Retinoids are the derivatives of vitamin A, consisting of β-ionone ring and isoprene chains. To this group of substances belong retinol, retinal, retinoic acid and their further metabolites and isomers. Their main task is to participate in the process of seeing and fetal development. From the point of view of dermatology and cosmetology, their very important task is their influence on differentiation and proliferation of epithelial cells and on the processes of exfoliation. This dissertation discusses skin diseases, in treatment of which retinoids are used. The thesis provides a short description of diseases with dosage, usage and approximate time of curation with retinoids. Scientific literature provides the most extensive description of acne (acne vulgaris) therapy using retinoid medications. These medications regulates processes of keratinization and normalizes seborrhea (seborrheic dermatitis), what restores patency of sebaceous glands and prevents their obstruction, in consequence restraining acne efflorescence. They reduce the inflammation by influencing conversion of arachidonic acid, dependent on lipoxygenase. Due to these processes, they limit the creation of erythema, occurrence of papules and pimples as well as reduce already arisen telangiectasia. Such properties make them very useful medications in rosacea therapy, however, they are still not registered to be used for this disease, and therefore such therapy is considered “off-label”. Due to their positive influence on the immune system, by regulating Langerhans cells’ functionality in the skin and restraining chemotactic factors, retinoids are the most often and very successfully applied in the therapy of psoriasis. As autoimmune diseases are a large issue nowadays, retinoids coming from different generation, e.g. isotretinoin, alitretinoin and acitretin, are used in the treatment of lupus erythematosus and other diseases. The influence of retinoids on proliferation and differentiation of epidermis, restraining excessive efflorescence, normalization of keratosis pilaris, when it occurs too slowly allows for treatment of many follicular and exfoliative diseases such as lichen planus or pityriasis rubra pilaris and other diseases causing disorders in inflammation process. Such diseases include different type of genodermatoses like Darier’s disease, ichthyosis or xeroderma pigmentosum. Wide spectrum of influence of vitamin A’s derivatives allows for the successful therapy skin changes coming from virus diseases. Thanks to influence on the processes of keratinization, retinoids can be used for the treatment of flat warts and water warts (molluscum contagiosum). As they cause plenty of side effects, they should not be applied as a first line therapy. Plenty clinical trials performer during last years, proved effectiveness of retinoids in prevention of formation and treatment of precancerous conditions as well as cancers (mostly skin cancer). Nowadays, many clinical trials are performed to check effectiveness of retinoid medications in the treatment of cancers of different etiology. Retinoids are also applied in cosmetic specimens. Especially, they are recommended for mature skin care, with signs of aging. They influence on the production of collagen and proliferation of fibroblasts, so that the skin becomes more hydrated and regenerated. They also reflect UV rays, so they are photoprotective. While using medications or cosmetics including vitamin A’s derivatives, many side effects must be taken into consideration. Among them is teratogenicity. Therefore, special care must be applied and the doctor should be consulted before using retinoids to find out about effective methods of contraception during and after the therapy

Wpływ obciążenia chorobami naczyniowymi na progresję łagodnych zaburzeń poznawczych do choroby Alzheimera

Introduction: Mild cognitive impairment does not meet the criteria for the diagnosis of dementia, but reaching this diagnosis raises concern about the future state of a patient due to the possibility of the conversion to Alzheimer’s disease. Although the aetiology of Alzheimer’s disease is neurodegenerative, the impact of vascular diseases is also taken into consideration. The aim of this study was to assess the impact of vascular diseases in patients diagnosed with mild cognitive impairment on the conversion to Alzheimer’s disease. Material and methods: In each of 101 patients with a diagnosis of mild cognitive impairment, a detailed medical history was taken, taking into account: hypertension, ischaemic heart disease, arrhythmias, myocardial infarction, stroke, diabetes as well as thyroid diseases, head injuries, alcohol abuse, smoking, exposure to toxic substances, surgery under general anaesthesia and the family character of dementia. Clinical follow-ups were scheduled after 6, 12 and 24 months. Results: Amongst 101 patients with mild cognitive impairment, 17 (16.8%) converted to Alzheimer’s disease within two years of observation. The analysis of the distribution of independence tests showed that the conversion is significant for two variables: ischaemic heart disease and myocardial infarction.Wstęp: Łagodne zaburzenia poznawcze nie spełniają kryteriów rozpoznania zespołu otępiennego, jednakże ustalenie tego rozpoznania wzbudza obawę o przyszły stan pacjenta, w związku z zagrożeniem konwersją do choroby Alzheimera. Mimo etiologii zwyrodnieniowej choroby Alzheimera brany pod uwagę jest również wpływ chorób naczyniowych na rozwój tej choroby. Celem pracy była ocena wpływu obciążenia chorobami naczyniowymi u pacjentów ze zdiagnozowanymi łagodnymi zaburzeniami poznawczymi na konwersję do choroby Alzheimera. Materiał i metody: U 101 pacjentów z rozpoznaniem łagodnych zaburzeń poznawczych przeprowadzono szczegółowy wywiad chorobowy, uwzględniający: nadciśnienie tętnicze, chorobę niedokrwienną serca, zaburzenia rytmu serca, zawał serca, udar mózgu, cukrzycę, a ponadto choroby tarczycy, urazy głowy, nadużywanie alkoholu, nikotynizm, kontakt z substancjami toksycznymi, operacje w znieczuleniu ogólnym i rodzinność otępienia. Zaplanowano wizyty kliniczne po 6, 12, 24 miesiącach. Wyniki: Spośród 101 pacjentów z rozpoznaniem łagodnych zaburzeń poznawczych u 17 osób (16,8%) stwierdzono konwersję do choroby Alzheimera w ciągu 2 lat obserwacji. Analiza testów niezależności rozkładów wykazała, że konwersja jest istotna dla dwóch zmiennych: choroby niedokrwiennej serca oraz zawału serca w wywiadzie

Impact of vascular diseases on the progression of mild cognitive impairment to Alzheimer’s disease

Introduction: Mild cognitive impairment does not meet the criteria for the diagnosis of dementia, but reaching this diagnosis raises concern about the future state of a patient due to the possibility of the conversion to Alzheimer’s disease. Although the aetiology of Alzheimer’s disease is neurodegenerative, the impact of vascular diseases is also taken into consideration. The aim of this study was to assess the impact of vascular diseases in patients diagnosed with mild cognitive impairment on the conversion to Alzheimer’s disease. Material and methods: In each of 101 patients with a diagnosis of mild cognitive impairment, a detailed medical history was taken, taking into account: hypertension, ischaemic heart disease, arrhythmias, myocardial infarction, stroke, diabetes as well as thyroid diseases, head injuries, alcohol abuse, smoking, exposure to toxic substances, surgery under general anaesthesia and the family character of dementia. Clinical follow-ups were scheduled after 6, 12 and 24 months. Results: Amongst 101 patients with mild cognitive impairment, 17 (16.8%) converted to Alzheimer’s disease within two years of observation. The analysis of the distribution of independence tests showed that the conversion is significant for two variables: ischaemic heart disease and myocardial infarction

Antibiotics sensitivity of Candida clinical and food-borne isolates

Candida is a yeast species recognized as the most frequent etiological agent of systemic and invasive thrush in humans. Invasions can affect all tissues, organs and systems of human in various stages of development. In the last 10 years Candida infections have increased 15 times. The purpose of our study was to determine the sensitivity of four antibiotics belonging to three different groups of antifungal agents against clinical and food-borne Candida strains. Our studies showed that of all tested strains, 7% was resistant to nystatin, 32% to fluconazole, 23% to voriconazole, and no strains grew in the presence of caspofungin. Despite the differences in biochemical profiles of clinical and food-borne isolates of Candida, a group of strains showing resistance to antibiotics include both types of isolates. At the same time circulating of antibiotic-resistant strains outside the hospital environment and the yeast infection via food is possible

Combined use of biochemical and volumetric biomarkers to assess the risk of conversion of mild cognitive impairment to Alzheimer’s disease

Introduction : The aim of our study was to evaluate the usefulness of several biomarkers in predicting the conversion of mild cognitive impairment (MCI) to Alzheimer’s disease (AD): β-amyloid and tau proteins in cerebrospinal fluid and the volumetric evaluation of brain structures including the hippocampus in magnetic resonance imaging (MRI). Material and methods : MRI of the brain with the volumetric assessment of hippocampus, entorhinal cortex, posterior cingulate gyrus, parahippocampal gyrus, superior, medial and inferior temporal gyri was performed in 40 patients diagnosed with mild cognitive impairment. Each patient had a lumbar puncture to evaluate β-amyloid and tau protein (total and phosphorylated) levels in the cerebrospinal fluid. The observation period was 2 years. Results : Amongst 40 patients with MCI, 9 (22.5%) converted to AD within 2 years of observation. Discriminant analysis was conducted and sensitivity for MCI conversion to AD on the basis of volumetric measurements was 88.9% and specificity 90.3%; on the basis of β-amyloid and total tau, sensitivity was 77.8% and specificity 83.9%. The combined use of the results of volumetric measurements with the results of proteins in the cerebrospinal fluid did not increase the sensitivity (88.9%) but increased specificity to 96.8% and the percentage of correct classification to 95%

Radiological evaluation of strategic structures in patients with mild cognitive impairment and early Alzheimer's disease

BACKGROUND: The aim of the study was to evaluate the diagnostic value of two measurement techniques in patients with cognitive impairment - automated volumetry of the hippocampus, entorhinal cortex, parahippocampal gyrus, posterior cingulate gyrus, cortex of the temporal lobes and corpus callosum, and fractional anisotropy (FA) index measurement of the corpus callosum using diffusion tensor imaging. MATERIAL AND METHODS: A total number of 96 patients underwent magnetic resonance imaging study of the brain - 33 healthy controls (HC), 33 patients with diagnosed mild cognitive impairment (MCI) and 30 patients with Alzheimer's disease (AD) in early stage. The severity of the dementia was evaluated with neuropsychological test battery. The volumetric measurements were performed automatically using FreeSurfer imaging software. The measurements of FA index were performed manually using ROI (region of interest) tool. RESULTS: The volumetric measurement of the temporal lobe cortex had the highest correct classification rate (68.7%), whereas the lowest was achieved with FA index measurement of the corpus callosum (51%). The highest sensitivity and specificity in discriminating between the patients with MCI vs. early AD was achieved with the volumetric measurement of the corpus callosum - the values were 73% and 71%, respectively, and the correct classification rate was 72%. The highest sensitivity and specificity in discriminating between HC and the patients with early AD was achieved with the volumetric measurement of the entorhinal cortex - the values were 94% and 100%, respectively, and the correct classification rate was 97%. The highest sensitivity and specificity in discriminating between HC and the patients with MCI was achieved with the volumetric measurement of the temporal lobe cortex - the values were 90% and 93%, respectively, and the correct classification rate was 92%. CONCLUSIONS: The diagnostic value varied depending on the measurement technique. The volumetric measurement of the atrophy proved to be the best imaging biomarker, which allowed the distinction between the groups of patients. The volumetric assessment of the corpus callosum proved to be a useful tool in discriminating between the patients with MCI vs. early AD