BACKGROUND: Human milk harbors diverse bacterial communities that contribute to infant health. Although pumping and storing milk is a common practice, the viable bacterial composition of pumped milk and the impact of storage practice on these bacteria remains under-explored. This metagenomic observational study aimed to characterize viable bacterial communities in freshly pumped human milk and its changes under different storage conditions. METHODS: In 2023, twelve lactating mothers from the CELSPAC: TNG cohort (Czech Republic) provided freshly pumped milk samples. These samples were stored under various conditions (refrigeration for 24 h, 48 h, or freezing for six weeks) and treated with propidium monoazide (PMA) to selectively identify viable cells. The DNA extracted from individual samples was subsequently analyzed using 16S rRNA amplicon sequencing on the Illumina platform. RESULTS: The genera Streptococcus, Staphylococcus, Diaphorobacter, Cutibacterium, and Corynebacterium were the most common viable bacteria in fresh human milk. The median sequencing depth and Shannon index of fresh human milk samples treated with PMA (+ PMA) were significantly lower than in untreated (-PMA) samples (p < 0.05 for all), which was true also for each time point. Also, significant changes in these parameters were observed between fresh human milk samples and their paired frozen samples (p < 0.05), while no differences were found between fresh human milk samples and those refrigerated for up to 48 h (p > 0.05). Of specific genera, only + PMA frozen human milk samples showed a significant decrease in the central log-ratio transformed relative abundances of the genera Diaphorobacter and Cutibacterium (p < 0.05) in comparison to + PMA fresh human milk samples. CONCLUSIONS: The study demonstrated that the bacterial profiles significantly differed between human milk samples treated with PMA, which represent only viable bacteria, and those untreated. While storage at 4 °C for up to 48 h did not significantly alter the overall diversity and composition of viable bacteria in human milk, freezing notably affected both the viability and relative abundances of some bacterial genera.
- MeSH
- azidy MeSH
- Bacteria * izolace a purifikace genetika klasifikace MeSH
- chlazení MeSH
- dospělí MeSH
- lidé MeSH
- mateřské mléko * mikrobiologie MeSH
- mikrobiota * MeSH
- propidium analogy a deriváty MeSH
- RNA ribozomální 16S MeSH
- skladování potravin * metody MeSH
- zmrazování MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- pozorovací studie MeSH
- MeSH
- antipyretika aplikace a dávkování farmakologie terapeutické užití MeSH
- chlazení metody MeSH
- glukokortikoidy aplikace a dávkování farmakologie terapeutické užití MeSH
- horečka * etiologie farmakoterapie MeSH
- hydratace organismu MeSH
- hypertermie etiologie farmakoterapie MeSH
- infekční nemoci etiologie farmakoterapie MeSH
- lidé MeSH
- nádory * komplikace MeSH
- paraneoplastické syndromy etiologie farmakoterapie MeSH
- protinádorové látky škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
The use of cryopreserved dolphin spermatozoa facilitates the exchange of genetic material between aquatic parks and makes spermatozoa accessible to laboratories for studies to further our understanding of marine mammal reproduction. Sperm cryopreservation in the bottlenose dolphin (Tursiops truncatus) has been developed for the exchange of gametes within the ex situ population. The aim of this study was to develop an effective method for refrigeration of bottlenose dolphin spermatozoa diluted in a commercial extender (BTS). In Experiment 1, the effect of temperature (5 compared with 15 °C) on sperm quality was evaluated during 7 days of storage at 100 × 106 spermatozoa/ml. In Experiment 2, the effect of the storage concentration (100 × 106 compared with 20 × 106 spermatozoa/ml) on sperm quality was assessed during 7 days of storage at 5 °C. In Experiment 1, total motility (including % of rapid sperm) was greater at 5 than 15 °C. When the effect of storage concentration was evaluated (Experiment 2), total motility and ALH were greater at the higher storage concentration (100 × 106 spermatozoa/ml). For both experiments, values for viability, acrosome integrity, and normal morphology variables were consistent throughout the 7 days of refrigeration. In Experiment 3, a microbiological study was performed to evaluate the effect of the refrigeration temperature and days of storage on bacterial growth. The results of microbiological analysis indicated there was Staphylococcus aureus in some samples, however, there was no effect of temperature or days of refrigeration. In conclusion, bottlenose dolphin semen can be refrigerated for a short to medium period of storage and there is maintenance of functionality of sperm when stored at 100 × 106 spermatozoa/ml at 5 °C.
The global SARS-CoV-2 pandemic dictates that anti-contagion strategies should become matters of essential routine in everyday life. Fomite transference is one of the routes of transmission that has been considered for this virus. However, the risks associated with contaminated surfaces of food packaging kept in refrigerators have not yet been adequately assessed. In this study, a surrogate virus, Alphacoronavirus 1, was used to investigate the persistence of coronavirus dried on a plastic carrier at 4 °C. Techniques of wet wiping, with or without disinfectant saturation, were employed to evaluate their effectiveness in the elimination of the virus. If not wiped, the loss of infectivity of the virus on plastic surfaces was, on average, 0.93 log10 (i.e. 83%) per day of storage at 4 °C. Wiping with water-saturated material reduced the initial virus titre on the plastic carrier by 2.4 log10 (99.6%); the same results were achieved through wiping with bactericidal wipes containing ethanol. Wipes saturated with a combination of disinfectant agents (didecyl-dimethyl-ammonium chloride, hydrogen peroxide) decreased the virus titre still more efficiently, by 3.8 log10 (99.98%) and also significantly prevented further transfer of the virus to a secondary surface through wiping. Thus SARS-CoV-2 transmission potential via contaminated plastic packaging and food may be efficiently eliminated by wet-wiping, especially when wipes saturated with specific disinfectants are used.
- MeSH
- antibakteriální látky MeSH
- Betacoronavirus MeSH
- bezpečnost potravin * MeSH
- chlazení * MeSH
- Coronavirus MeSH
- COVID-19 MeSH
- dezinfekce metody MeSH
- dezinficiencia MeSH
- ethanol MeSH
- fomity virologie MeSH
- koronavirové infekce epidemiologie prevence a kontrola virologie MeSH
- kvartérní amoniové sloučeniny MeSH
- lidé MeSH
- obaly potravin * MeSH
- pandemie prevence a kontrola MeSH
- peroxid vodíku MeSH
- plastické hmoty * MeSH
- SARS-CoV-2 MeSH
- skladování potravin metody MeSH
- virová pneumonie epidemiologie prevence a kontrola virologie MeSH
- voda MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Klíčová slova
- chlazení hlavy,
- MeSH
- alopecie * prevence a kontrola MeSH
- chlazení metody MeSH
- hlava MeSH
- lidé MeSH
- nádory prsu farmakoterapie MeSH
- protinádorové látky škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
Intoxication by staphylococcal enterotoxins (SE) is among the most common causes of food-poisoning outbreaks resulting from the consumption of raw milk or products made thereof. The aim of our study was to analyze the thermal stability of SE and evaluate the inactivation of SE types A, B, and C (SEA, SEB, SEC) by autoclaving at 100°C, 110°C, and 121°C. Milk samples were inoculated with 38 Staphylococcus aureus strains that possessed the ability to produce SEA, SEB, or SEC and incubated at 37°C for 24 h. This incubation was followed by heat treatment at 100°C, 110°C, or 121°C for 3 min. Samples were analyzed by Staph. aureus plate count method on Baird-Parker agar and specifically for the presence of SE. An enzyme-linked immunofluorescent assay (ELFA) on a MiniVIDAS analyzer (bioMérieux, Marcy l'Étoile, France) was used to detect SE, which were determined semi-quantitatively based on test values. The obtained results were analyzed by means of nonparametric statistical methods. All samples (100%; 38/38) were SE-positive before heat treatment, and the positivity rates decreased after heat treatment at 100°C, 110°C, and 121°C to 36.8% (14/38), 34.2% (13/38), and 31.6% (12/38), respectively. The rates of positive samples differed between SEA, SEB, and SEC producers: SEA was detected in the highest amounts both before and after heat treatment. The amount of SE (expressed as test values) decreased significantly after heat treatment. Comparing amounts of SE in positive and negative samples before and after heat treatment, we can conclude that the success of SE inactivation depends on the amount present before heat treatment. The highest amount of SE and the highest rate of SE-positive samples after all heat treatments were found in samples with strains producing SEA. For SEB and SEC, lower amounts of enterotoxin were present and were inactivated at 100°C. Although temperatures of 100°C, 110°C, and 121°C may inactivate SE in milk, the key measures in prevention of staphylococcal enterotoxicosis are avoiding initial contamination of milk by Staph. aureus, promoting consumption of heat-treated milk, and preventing disruption of the cold chain during milk production and processing.
- MeSH
- chlazení MeSH
- enterotoxiny analýza chemie MeSH
- mastitida skotu mikrobiologie MeSH
- mléko chemie mikrobiologie MeSH
- potravinářská mikrobiologie metody MeSH
- skot MeSH
- stabilita léku MeSH
- stafylokokové infekce veterinární MeSH
- Staphylococcus aureus metabolismus MeSH
- vysoká teplota * MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- chlazení metody MeSH
- lidé MeSH
- předškolní dítě MeSH
- rozvojové země MeSH
- skladování léků * metody MeSH
- vakcinace MeSH
- vakcíny * zásobování a distribuce MeSH
- Check Tag
- lidé MeSH
- předškolní dítě MeSH
- Publikační typ
- práce podpořená grantem MeSH
V letech 2015 a 2016 šetřili pracovníci Krajské hygienické stanice Moravskoslezského kraje se sídlem v Ostravě (KHS MSK) onemocnění legionelózou u třech osob pracujících v průmyslových areálech, které přišly do kontaktu s aerosolem teplé vody ze sprch a aerosolem technologické vody chladicích věží. Kolektiv autorů se zabývá průkazem spojitosti vzniku onemocnění a kontaminované matrice - aerosolu teplé vody ze sprch a aerosolu technologické vody chladicích věží, přičemž dochází k závěru, že šetřená onemocnění byla způsobena kontaminovanou technologickou vodou otevřených okruhů chladicích věží. Ke kazuistikám onemocnění je v článku přiřazeno environmentální šetření odebraných vod, včetně identifikace původce nákazy pomocí biologických molekulárních metod ve vodách chladicích věží.
Between 2015 and 2016, workers from the Regional Public Health Authority of the Moravian Silesian Region (RPHA) examined legionella disease in three people working in industrial premises, which came into contact with hot water aerosol from showers and the aerosol of technological water of cooling towers. The team of authors deals with the demonstration of the connection the of disease with the contaminated matrix - the aerosol of hot water from the showers and aerosol of technological water of the cooling towers, concluding that the investigated diseases were caused by the contaminated technological water of the open circuits of the cooling towers. Cases of the disease are supplement with an environmental survey of collected water, including the identification of the origin of the disease by means of biological molecular methods in the water of the cooling towers.
- MeSH
- chlazení přístrojové vybavení MeSH
- hygiena práce MeSH
- Legionella MeSH
- legionelóza * etiologie přenos MeSH
- lidé MeSH
- nemoci z povolání * MeSH
- potravinářský průmysl přístrojové vybavení MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
