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Microbiology Spectrum Jun 2023The lacustrine systems of La Brava and La Punta, located in the Tilopozo sector in the extreme south of Salar de Atacama, are pristine high-altitude Andean lakes found...
The lacustrine systems of La Brava and La Punta, located in the Tilopozo sector in the extreme south of Salar de Atacama, are pristine high-altitude Andean lakes found along the central Andes of South America. This shallow ecosystem suffers from permanent evaporation, leading to falling water levels, causing it to recede or disappear during the dry season. This dynamic causes physicochemical changes in lakes, such as low nutrient availability, pH change, and dissolved metals, which can influence the composition of the microbial community. In this study, we used a metataxonomic approach (16S rRNA hypervariable regions V3 to V4) to characterize the sedimentary microbiota of these lakes. To understand how the water column affects and is structured in the microbiota of these lakes, we combined the analysis of the persistence of the water column through satellite images and physicochemical characterization. Our results show a significant difference in abiotic factors and microbiota composition between La Punta and La Brava lakes. In addition, microbiota analysis revealed compositional changes in the ecological disaggregation (main and isolated bodies) and antagonistic changes in the abundance of certain taxa between lakes. These findings are an invaluable resource for understanding the microbiological diversity of high Andean lakes using a multidisciplinary approach that evaluates the microbiota behavior in response to abiotic factors. In this study, we analyzed the persistence of the water column through satellite images and physicochemical characterization to investigate the composition and diversity in High Andean Lake Systems in a hyperarid environment. In addition to the persistence of the water column, this approach can be used to analyze changes in the morphology of saline accumulations and persistence of snow or ice; for example, for establishing variable plant cover over time and evaluating the microbiota associated with soils with seasonal changes in plants. This makes it an ideal approach to search for novel extremophilic microorganisms with unique properties. In our case, it was used to study microorganisms capable of resisting desiccation and water restriction for a considerable period and adapting to survive in ecological niches, such as those with high UV irradiation, extreme drought, and high salt concentration.
Topics: Lakes; Seasons; Water; RNA, Ribosomal, 16S; Altitude; Microbiota
PubMed: 37102964
DOI: 10.1128/spectrum.05200-22 -
Wellcome Open Research 2023Interferon-γ (IFN-γ) secretion by T cells is a key correlate of immune protection against many pathogens including tuberculosis and the neglected tropical disease...
Interferon-γ (IFN-γ) secretion by T cells is a key correlate of immune protection against many pathogens including tuberculosis and the neglected tropical disease melioidosis. Clinical studies in tropical regions of immune responses to pathogens and vaccine monitoring studies require the collection of samples in resource-limited rural areas and subsequent shipment to central laboratories for downstream assays and long-term storage. Here, we studied the impact of two different shipping temperatures on the viability, composition and function of peripheral blood mononuclear cells (PBMC) using multi-colour flow cytometry and IFN-γ enzyme-linked immunospot assay (IFN-γ ELISpot), in order to provide guidance on sample shipment conditions for future clinical studies. Paired peripheral blood mononuclear cell (PBMC) samples from recovered melioidosis patients were stored in liquid nitrogen (-196°C) and then shipped from Bangkok, Thailand to Oxford, UK at either -80°C (dry ice) or -196°C (dry shipper). After thawing, cell viability and composition were assessed by flow cytometry and antigen specific responses to (BP) were measured using IFN-γ ELISpot. We observed modest lowering of viability in the majority of samples and a reduction in IFN-γ responses to BP which correlated to a decrease of monocytes and natural killer cells in samples shipped at -80°C compared to -196°C. Despite being lower in magnitude antigen-specific responses remained detectable in the majority of samples. Here we demonstrate that shipment of cryopreserved PBMC at -196°C has a benefit on cell viability, recovery and T cell responses to bacterial antigens, although useful information can still be obtained from samples shipped at -80°C, thus providing important guidance for sample management in future clinical trials.
PubMed: 38903244
DOI: 10.12688/wellcomeopenres.18822.1 -
Upsala Journal of Medical Sciences 2023More than two in five Swedish women are overweight or obese when becoming pregnant. Maternal overweight or obesity and excessive pregnancy weight gain are associated...
BACKGROUND
More than two in five Swedish women are overweight or obese when becoming pregnant. Maternal overweight or obesity and excessive pregnancy weight gain are associated with several adverse pregnancy outcomes. The underlying mechanisms that link maternal adiposity, diet, exercise, pregnancy weight gain with pregnancy outcome are incompletely understood.
METHODS
We describe the design for a cross-sectional study of pregnant women at Uppsala University Hospital, Sweden. All participants delivered by elective cesarean section before the onset of labor. At inclusion, participants answered two questionnaires concerning their dietary and exercise habits. Fasting maternal blood samples (buffy coat, plasma, serum) were collected. During the cesarean section, biopsies of maternal subcutaneous and visceral adipose tissues were obtained. Placental tissue was collected after delivery. All biological samples were processed as soon as possible, frozen on dry ice, and stored at -70 °C. Pregnancy outcomes and supplementary maternal characteristics were collected from medical records.
RESULTS
In total, 143 women were included in the study. Of these women, 33.6% were primiparous, 46.2% had a pre-pregnancy body mass index (BMI) over 25 kg/m, and 11.2% of the offspring were born large for gestational age (LGA). Complete collection, that is both questionnaires and all types of biological samples, was obtained from 81.1% of the participants.
CONCLUSIONS
This study is expected to provide a resource for exploration of the associations between maternal weight, diet, exercise, pregnancy weight gain, and pregnancy outcome. Results from this study will be published in peer-reviewed, international scientific journals. This study was approved by the Regional Ethics Review Board in Uppsala (approval no 2014/353) and with an amendment by the Swedish Ethical Review Authority (approval no 2020-05844).
Topics: Female; Pregnancy; Humans; Overweight; Cross-Sectional Studies; Gestational Weight Gain; Cesarean Section; Placenta; Weight Gain; Obesity; Pregnancy Outcome; Body Mass Index
PubMed: 37056481
DOI: 10.48101/ujms.v128.8832 -
Nature Communications Apr 2023Ice-rich Pleistocene-age permafrost is particularly vulnerable to rapid thaw, which may quickly expose a large pool of sedimentary organic matter (OM) to microbial...
Ice-rich Pleistocene-age permafrost is particularly vulnerable to rapid thaw, which may quickly expose a large pool of sedimentary organic matter (OM) to microbial degradation and lead to emissions of climate-sensitive greenhouse gases. Protective physico-chemical mechanisms may, however, restrict microbial accessibility and reduce OM decomposition; mechanisms that may be influenced by changing environmental conditions during sediment deposition. Here we study different OM fractions in Siberian permafrost deposited during colder and warmer periods of the past 55,000 years. Among known stabilization mechanisms, the occlusion of OM in aggregates is of minor importance, while 33-74% of the organic carbon is associated with small, <6.3 µm mineral particles. Preservation of carbon in mineral-associated OM is enhanced by reactive iron minerals particularly during cold and dry climate, reflected by low microbial CO production in incubation experiments. Warmer and wetter conditions reduce OM stabilization, shown by more decomposed mineral-associated OM and up to 30% higher CO production. This shows that considering the stability and bioavailability of Pleistocene-age permafrost carbon is important for predicting future climate-carbon feedback.
PubMed: 37055417
DOI: 10.1038/s41467-023-37766-5 -
International Journal of Molecular... Mar 2023Climate changes abruptly affect optimum growth temperatures, leading to a negative influence on plant physiology and productivity. The present study aimed to investigate...
Climate changes abruptly affect optimum growth temperatures, leading to a negative influence on plant physiology and productivity. The present study aimed to investigate the extent of low-temperature stress effects on date palm growth and physiological indicators under the exogenous application of silicon (Si). Date palm seedlings were treated with Si (1.0 mM) and exposed to different temperature regimes (5, 15, and 30 °C). It was observed that the application of Si markedly improved fresh and dry biomass, photosynthetic pigments (chlorophyll and carotenoids), plant morphology, and relative water content by ameliorating low-temperature-induced oxidative stress. Low-temperature stress (5 and 15 °C), led to a substantial upregulation of ABA-signaling-related genes ( and ) in non Si treated plants, while Si treated plants revealed an antagonistic trend. However, jasmonic acid and salicylic acid accumulation were markedly elevated in Si treated plants under stress conditions (5 and 15 °C) in comparison with non Si treated plants. Interestingly, the upregulation of low temperature stress related plant plasma membrane ATPase ( and ) and short-chain dehydrogenases/reductases (), responsible for cellular physiology, stomatal conductance and nutrient translocation under silicon applications, was observed in Si plants under stress conditions in comparison with non Si treated plants. Furthermore, a significant expression of was detected in Si plants under stress, leading to the significant accumulation of Si in roots and shoots. In contrast, non Si plants demonstrated a low expression of under stress conditions, and thereby, reduced level of Si accumulation were observed. Less accumulation of oxidative stress was evident from the expression of and . Additionally, Si plants revealed a significant exudation of organic acids (succinic acid and citric acid) and nutrient accumulation (K and Mg) in roots and shoots. Furthermore, the application of Si led to substantial upregulation of the low temperature stress related soybean cold regulated gene () and (), involved in the expression of CBF/DREB (C-repeat binding factor/dehydration responsive element binding factor) gene family under stress conditions in comparison with non Si plants. The current research findings are crucial for exploring the impact on morpho-physio-biochemical attributes of date palms under low temperature and Si supplementation, which may provide an efficient strategy for growing plants in low-temperature fields.
Topics: Silicon; Phoeniceae; Antioxidants; Temperature; Oxidative Stress
PubMed: 37047009
DOI: 10.3390/ijms24076036 -
International Journal of Circumpolar... Dec 2023A field study was conducted to examine the vulnerability of military divers to non-freezing cold injury (NFCI) during Arctic ice-diving operations. Participants were...
A field study was conducted to examine the vulnerability of military divers to non-freezing cold injury (NFCI) during Arctic ice-diving operations. Participants were instrumented with temperature sensors on the back of their hands and on the bottom of their big toe for each dive to measure cooling of their extremities. While NFCI was not diagnosed in any of the participants during this field study, the data indicate that the feet were particularly vulnerable during the dives given that they were mostly in a temperature zone that could cause pain and performance decrements. The data also show that for short term dives, the dry and wet suits with wet gloves in both configurations were thermally more comfortable for the hands than the dry suit with dry glove configuration; however, the latter would be more protective against potential NFCI during longer dives. Features such as hydrostatic pressure and repetitive diving that are unique to diving but not previously considered as risk factors for NFCI are examined herein and warrant deeper investigation given that symptoms of NFCI might be mistaken as decompression sickness.
Topics: Humans; Diving; Cold Temperature; Temperature; Arctic Regions; Extremities
PubMed: 36966493
DOI: 10.1080/22423982.2023.2190488 -
International Journal of Pharmaceutics Apr 2023Biopharmaceuticals are administered parenterally and therefore sterility is required. Sterility can be obtained via different processes including exposure to steam or...
Biopharmaceuticals are administered parenterally and therefore sterility is required. Sterility can be obtained via different processes including exposure to steam or dry heat. Sterilisation studies on biopharmaceuticals, which are highly sensitive medicinal products, are scarce. This study investigates the effect of different sterilisation processes on recombinant human insulin in solid state (gamma and e-beam irradiation (w/wo dry ice), nitrogen dioxide (NO)) and in aqueous solution (gamma irradiation (w/wo dry ice, w/wo glycerin)) using ultra-high performance liquid chromatography-diode array detection-mass spectrometry. It is observed that NO substantially degrades the solid samples, while gamma and e-beam irradiation result in lower levels of degradation (mean normalized peak areas of 95.2-96.2 % with respect to the non-sterilised samples). Gamma irradiation of insulin solutions with and without dry ice at 2.5 kGy results in mean normalised peak areas of 85 % and <40 % with respect to the non-sterilised samples, respectively. It is concluded that sterilisation using ionising radiation of liquid biopharmaceuticals with insulin and sterilisation of insulin dry powder using NO is less suitable with the set-ups used here because of substantial degradation. In contrast, evidence is presented in favour of sterilisation of insulin dry powder using ionising radiation.
Topics: Humans; Nitrogen Dioxide; Biological Products; Powders; Dry Ice; Gamma Rays; Insulin; Sterilization
PubMed: 36934881
DOI: 10.1016/j.ijpharm.2023.122867 -
Experimental & Applied Acarology Feb 2023Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne infectious disease caused by Dabie bandavirus, commonly called SFTS virus (SFTSV). In the Republic of...
Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne infectious disease caused by Dabie bandavirus, commonly called SFTS virus (SFTSV). In the Republic of Korea (ROK), 1,504 cases of SFTS have been reported since the first human case was identified in 2013 until 2021. However, no case exists to provide molecular evidence between questing tick and patients with confirmed SFTS in the same living environment. In this study, we investigated the presence of ticks near the area of a patient infected with SFTSV. Ticks were collected by flagging and dry ice-baited traps at three spots in the vegetation around the patients' residence in Chuncheon City, Gangwon Province (ROK). Among the tick samples collected, the presence of SFTSV was genetically determined using reverse transcription PCR, followed by the phylogenetic analysis of the tick virus sequences and SFTSV found in the patient. In total 1,212 Haemaphysalis longicornis ticks were collected, and SFTSV was detected at a minimum infection rate of 5.3% (33 pools/618 tested ticks). The sequences of SFTSV in ticks were 99.6-100% identical with the patient's SFTSV in the M segment. To the best of our knowledge, this study is the first case to provide a molecular correlation between SFTSV in questing ticks collected from residence and patient with SFTS in the ROK. The present results provide useful information for the epidemiological investigation of patients with SFTS using ticks as vectors of SFTSV.
Topics: Humans; Animals; Ticks; Severe Fever with Thrombocytopenia Syndrome; Phylogeny; Phlebovirus; Republic of Korea
PubMed: 36928542
DOI: 10.1007/s10493-023-00783-6 -
Clinical Ophthalmology (Auckland, N.Z.) 2023Validation of the novel Lexitas modified NEI scale for use in assessment of corneal fluorescein staining.
PURPOSE
Validation of the novel Lexitas modified NEI scale for use in assessment of corneal fluorescein staining.
PATIENTS AND METHODS
A series of 18 illustrations and 14 clinical photographs depicting varying severity levels of corneal fluorescein staining were assessed by 3 independent examiners. Regions of the cornea were graded for staining severity based on 3 different grading scales: the original NEI staining scale (density-based scoring; 0-3 scale), a structured version of the NEI scale (dot-count scoring; 0-3 scale), and the Lexitas modified NEI staining scale (0-4 scale with half-point increments). Kappa statistics (simple and weighted) were computed to determine intra-examiner image grading repeatability for each examiner over 2 separate assessments. Inter-examiner assessment reliability utilized the scores from the first read of each examiner, and pairs of examiners to compute kappa statistics.
RESULTS
Data was analyzed from the scores provided by the examiners from each gradable corneal region on 32 images (18 illustrations and 14 photographs) for a total of 154 corneal regions across the 3 grading scales for each validation run. The mean intra-examiner simple/weighted kappa values using the NEI density, NEI dot count, and the Lexitas modified NEI staining scales were 0.67/0.72, 0.91/0.94, 0.80/0.92 for the graded illustrations, and 0.83/0.88, 0.76/0.85, 0.77/0.88 for the graded photographs, respectively. The mean inter-examiner simple/weighted kappa values using the NEI density, NEI dot count, and the Lexitas modified NEI staining scales were 0.59/0.65, 0.86/0.90, and 0.78/0.91 for the graded illustrations, and 0.80/0.88, 0.84/0.89, 0.69/0.88 for the graded photographs, respectively.
CONCLUSION
The expanded scale of the Lexitas modified NEI staining scale demonstrated a high degree of reliability and repeatability of grading assessments within and across individual examiners, comparing favorably with the original NEI staining scale. A future investigation into the in-office utility of the Lexitas modified NEI staining scale is warranted.
PubMed: 36915716
DOI: 10.2147/OPTH.S398843 -
Physiology and Molecular Biology of... Feb 2023Drought alters rice morphophysiology and reduces grain yield. This study hypothesized that the combined analysis of morphophysiological and agronomic traits enables a...
UNLABELLED
Drought alters rice morphophysiology and reduces grain yield. This study hypothesized that the combined analysis of morphophysiological and agronomic traits enables a systemic approach to responses to water deficit, allowing the selection of resistance markers to upland rice. The objectives were to evaluate the effects of water deficit applied at the reproductive stage in plant water status, leaf gas exchanges, leaf non-structural carbohydrate contents, and agronomic traits in upland rice genotypes; and to verify if the analyzed variables may be applied to group the genotypes according to their tolerance level. Water deficit was induced by irrigation suppression in eight genotypes at R2-R3. Physiological and biochemical traits were evaluated at the end of the water deficit period, thenceforth irrigation was restored until grain maturation for the analysis of the agronomic traits. Water deficit reduced: Ψ (63.64%, average); g (28-90%); transpiration rate (40.63-65.45%); RWC from Serra Dourada to Esmeralda (43.36-61.48%); net CO assimilation from Serra Dourada to Primavera (70.04-99.91%); WUE from Esmeralda to Primavera (83.98-99.85%); CE in Esmeralda (99.92%); 100-grain weight in CIRAD and Soberana (13.65-20.63%); and grain yield from Primavera to IAC 164 (34.60-78.85%). Water deficit increased C from Cambará to Early mutant (79.64-215.23%), and did not affect the tiller number, shoot dry biomass, fructose, and sucrose contents. The alterations in the variables distinguished groups according to the water regime. RWC, Ψ, leaf gas exchanges, and CE were valuable traits to distinguish the water regime treatments, but not to group the genotypes according to the drought tolerance level.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s12298-023-01287-8.
PubMed: 36875723
DOI: 10.1007/s12298-023-01287-8