Application of ImageJ program to the enumeration of Orientia tsutsugamushi organisms cultured in vitro

GelMA loaded with platelet lysate promotes skin regeneration and angiogenesis in pressure ulcers by activating STAT3

Pressure ulcers (PU) are caused by persistent long-term pressure, which compromises the integrity of the epidermis, dermis, and subcutaneous adipose tissue layer by layer, making it difficult to heal. Platelet products such as platelet lysate (PL) can promote tissue regeneration by secreting numerous growth factors based on clinical studies on skin wound healing. However, the components of PL are difficult to retain in wounds. Gelatin methacrylate (GelMA) is a photopolymerizable hydrogel that has lately emerged as a promising material for tissue engineering and regenerative medicine. The PL liquid was extracted, flow cytometrically detected for CD41a markers, and evenly dispersed in the GelMA hydrogel to produce a surplus growth factor hydrogel system (PL@GM). The microstructure of the hydrogel system was observed under a scanning electron microscope, and its sustained release efficiency and biological safety were tested in vitro. Cell viability and migration of human dermal fibroblasts, and tube formation assays of human umbilical vein endothelial cells were applied to evaluate the ability of PL to promote wound healing and regeneration in vitro. Real-time polymerase chain reaction (PCR) and western blot analyses were performed to elucidate the skin regeneration mechanism of PL. We verified PL's therapeutic effectiveness and histological analysis on the PU model. PL promoted cell viability, migration, wound healing and angiogenesis in vitro. Real-time PCR and western blot indicated PL suppressed inflammation and promoted collagen I synthesis by activating STAT3. PL@GM hydrogel system demonstrated optimal biocompatibility and favorable effects on essential cells for wound healing. PL@GM also significantly stimulated PU healing, skin regeneration, and the formation of subcutaneous collagen and blood vessels. PL@GM could accelerate PU healing by promoting fibroblasts to migrate and secrete collagen and endothelial cells to vascularize. PL@GM promises to be an effective and convenient treatment modality for PU, like chronic wound treatment.

A standardized and efficient technique to estimate seed traits in plants with numerous small propagules

Premise

Variation in seed traits is common within and among populations of plant species and often has ecological and evolutionary implications. However, due to the time-consuming nature of manual seed measurements and the level of variability in imaging techniques, quantifying and interpreting the extent of seed variation can be challenging.

Methods

We developed a standardized high-throughput technique to measure seed number, as well as individual seed area and color, using a derived empirical scale to constrain area in Arabidopsis thaliana, Brassica rapa, and Mimulus guttatus. We develop a specific rational model using seed area measured at various spatial scales relative to the pixel count, observing the asymptotic value of the seed area as the modeled number of pixels approaches infinity.

Results

We found that our model has high reliability in estimating seed traits and efficiently processes large numbers of images, facilitating the quantification of seed traits in studies with large sample sizes.

Discussion

This technique facilitates consistency between imaging sessions and standardizes the measurement of seed traits. These novel advances allow researchers to directly and reliably measure seed traits, which will enable tests of the ecological and evolutionary causes of their variation.

Can Superoxide Anions Predict the Malignant Potential of Carotid body Tumor? - A Pilot Study

Currently, there is no consensus on estimating the malignant potential of Carotid Body Tumor (CBT) and the only way to predict a metastatic CBT is through DOTANOC Positron Emission Tomography (PET) scan. There is a well-established correlation between CBT and superoxide anions inside tumor cells. The purpose of this pilot study was to measure superoxide anions inside CBT cells and find if these can be used as marker to predict malignant potential of CBT. The results were also co-related with findings of DOTANOC PET scan retrospectively. The CBT tissue from 10 patients was stained using a fluorogenic dye and superoxide anions were measured by analysis of fluorescent image. The patients were divided into two groups - First group with four patients having potentially malignant CBT based upon clinico-surgical characteristics and second group with the rest of the six patients. It was seen that the superoxide anions were highest in the first group which included patients with metastatic carotid body tumor, patients with multiple paragangliomas and patient with positive family history (p = 0.011). The same patients also had metastasis and multiple tumors detected on DOTANOC PET scan. It was concluded that measuring superoxide anions in excised tumor tissue can be used to estimate malignant potential of CBT and can identify patients who truly require DOTANOC PET scan; without affecting the treatment, as it is an expensive investigation involving ionizing radiation and may not be available in all centres.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-03623-6.

A Semi-Automatic Method for the Quantification of Astrocyte Number and Branching in Bulk Immunohistochemistry Images

Immunohistochemical staining of cell and molecular targets in brain samples is a powerful tool that can provide valuable information on neurological mechanisms. However, post-processing of photomicrographs acquired after 3,3'-Diaminobenzidine (DAB) staining is particularly challenging due to the complexity associated with the size, samples number, analyzed targets, image quality, and even the subjectivity inherent to the analysis by different users. Conventionally, this analysis relies on the manual quantification of distinct parameters (e.g., the number and size of cells and the number and length of cell branching) in a large set of images. These represent extremely time-consuming and complex tasks, defaulting the processing of high amounts of information. Here we describe an improved semi-automatic method to quantify glial fibrillary acidic protein (GFAP)-labelled astrocytes in immunohistochemistry images of rat brains, at magnifications as low as 20×. This method is a straightforward adaptation of the Young & Morrison method, using ImageJ's plugin Skeletonize, coupled with intuitive data processing in datasheet-based software. It allows swifter and more efficient post-processing of brain tissue samples, regarding astrocyte size and number quantification, the total area occupied, as well as astrocyte branching and branch length (indicators of astrocyte activation), thus contributing to better understand the possible inflammatory response developed by astrocytes.

Rumen Ciliated Protozoa of the Free-Living European Bison (Bison bonasus, Linnaeus)

This study aims to perform population analysis of the rumen ciliated protozoa of the free-living European bison (wisent, Bison bonasus, Linnaeus). The samples of the rumen fluid from the 18 bison subjected to the controlled culls within the free-ranging population in the Bialowieza primeval forest in Poland were collected and examined. The examined ciliates population consisted of the species of the families Isotrichidae and Ophryoscolecidae. There were 12 genera (Isotricha, Dasytricha, Diplodinium, Elytroplastron, Entodinium, Eodinium, Epidinium, Eremoplastron, Eudiplodinium, Metadinium, Ophryoscolex, and Ostracodinium) and 32 morphospecies of the ciliates. We observed the prevalence of a type B protozoan population (56% animals) with the typical Epidinium and Eudiplodinium genera members. Other examined animals possessed the mixed A-B population with Ophryoscolex genus, distinct for type A ciliate population. The average total ciliates count was 2.77 ± 1.03 × 105/ml (mean ± SD). The most abundant genera were Entodinium, 83%, and Dasytricha, 14%. The abundance of other genera was <1% of the total count. Within the 16 Entodinium species determined, the most abundant species was Entodinium nanellum (16.3% of total ciliates count). The average Shannon-Wiener diversity index was 2.1 ± 0.39, evenness was 0.7 ± 0.11, and species richness was 24 ± 3.0 (mean ± SD). Our study is the first report on the population composition and diversity of rumen ciliates of European bison. The composition and counts of ciliate genera and species were similar to the composition and counts of the rumen ciliated protozoa of American bison and many other kinds of free-living and domestic ruminants. Our European bison ciliate population analysis has shown medium ciliate density and high diversity typical for large free-living ruminants with mixed feeding behavior.

A Clonogenic Assay to Quantify Melanoma Micrometastases in Pulmonary Tissue

Metastatic melanoma is one of the most aggressive types of cancers, diffused worldwide and with a significant percentage of lethality. The employment of animal models to test therapeutic strategies against melanoma growth and metastatic spread is of key relevance for cancer biologists. In this regard, the count of metastatic foci in murine lung tissue is one of the recognized methods to monitor macrometastases of melanoma. Here, we illustrate a clonogenic assay method to detect with high sensitivity the presence of single melanoma cells (micrometastases) at the pulmonary level when metastatic foci are still not detectable in the tissue. This method allows for high precision detection and quantification of melanoma metastatic spread to the lung at early stages.

Long-Term Evaluation of Mesophilic Semi-Continuous Anaerobic Digestion of Olive Mill Solid Waste Pretreated with Steam-Explosion

Steam-explosion is a promising technology for recovering phenolic compounds from olive mill solid waste (OMSW) due to its high impact on the structure of the fibre. Moreover, the recovery of the phenols, which are well-known microbial inhibitors, could improve the subsequent biomethanization of the dephenolized OMSW to produce energy. However, there is a considerable lack of knowledge about how the remaining phenolic compounds could affect a long-term biomethanization process of steam-exploded OMSW. This work evaluated a semi-continuous mesophilic anaerobic digestion of dephenolized steam-exploited OMSW during a long operational period (275 days), assessing different organic loading rates (OLRs). The process was stable at an OLR of 1 gVS/(L·d), with a specific production rate of 163 ± 28 mL CH4/(gVS·d). However, the increment of the OLR up to 2 gVS/(L·d) resulted in total exhaust of the methane production. The increment in the propionic acid concentration up to 1486 mg/L could be the main responsible factor for the inhibition. Regardless of the OLR, the concentration of phenolic compounds was always lower than the inhibition limits. Therefore, steam-exploited OMSW could be a suitable substrate for anaerobic digestion at a suitable OLR.

Influence of growth phase on the harvesting of Scenedesmus acuminatus using ultrafiltration

Cellular characteristics and algogenic organic matter (AOM) properties change with culture time. This study aims to understand the changes throughout the growth phase, and their effect on Scenedesmus acuminatus harvesting using ultrafiltration. The variations in cellular particle size distribution, cellular EPS content, and the biochemical composition and molecular weight of AOM were analyzed, followed by the membrane harvesting of the original S. acuminatus suspension, AOM-free cells and cell-free AOM. The results showed that the average flux for the original suspension increased with growth phase and reached an increase of 36.3% in the declining phase. AOM played a greater role than S. acuminatus cells in flux decline for all growth phases. Exponential-phase AOM contained a greater high-MW fraction and more carbohydrates, and the exponential cells were smaller cells and had a higher EPS content; these characteristics resulted in a reduced average flux.

Performance evaluation of mesophilic semi-continuous anaerobic digestion of high-temperature thermally pre-treated olive mill solid waste

The aim of the present work was to evaluate the effects of a thermal pre-treatment of olive mill solid waste (OMSW) and phenol extraction process on the semi-continuous anaerobic digestion of this pre-treated waste during a prolonged operational period (275 days) in order to assess the organic loading rates (OLR) of 1 ad 2 g Volatile Solids (VS)/(L·d). The anaerobic digestion of thermally pre-treated and de-phenolized OMSW was stable at an OLR of 1 g VS/(L·d), which permitted a specific production rate of 172 ± 60 mL CH₄/(g VS·d). However, the system was not able to operate at an OLR of 2 g VS/(L·d), which resulted in the total failure of the process. Regardless of the applied OLR, the phenolic compounds were effectively degraded and the inhibition thresholds were not reached. The inhibition of the anaerobic digestion process at an OLR of 2 g VS/(L·d) was probably due to the overloading of the system, indicated by the accumulation of organic matter and volatile fatty acids. The operation of the anaerobic digester under stable conditions allowed for high profitability for the proposed bio-refinery concept, which would still be profitable at a phenol extract price above 51.8 €/kg, which is 90% lower than the current price of 520 €/kg.

Automated quantitative image analysis for ex vivo metastasis assays reveals differing lung composition requirements for metastasis suppression by KISS1

Imaging is broadly used in biomedical research, but signal variation complicates automated analysis. Using the Pulmonary Metastasis Assay (PuMA) to study metastatic colonization by the metastasis suppressor KISS1, we cultured GFP-expressing melanoma cells in living mouse lung ex vivo for 3 weeks. Epifluorescence images of cells were used to measure growth, creating large datasets which were time consuming and challenging to quantify manually due to scattering of light from outside the focal plane. To address these challenges, we developed an automated workflow to standardize the measurement of disseminated cancer cell growth by applying statistical quality control to remove unanalyzable images followed and a filtering algorithm to quantify only in-focus cells. Using this tool, we demonstrate that expression of the metastasis suppressor KISS1 does not suppress growth of melanoma cells in the PuMA, in contrast to the robust suppression of lung metastasis observed in vivo. This result may suggest that a factor required for metastasis suppression is present in vivo but absent in the PuMA, or that KISS1 suppresses lung metastasis at a step in the metastatic cascade not tested by the PuMA. Together, these data provide a new tool for quantification of metastasis assays and further insight into the mechanism of KISS1 mediated metastasis suppression in the lung.

A Review of Scrub Typhus (Orientia tsutsugamushi and Related Organisms): Then, Now, and Tomorrow

Scrub typhus and the rickettsial diseases represent some of the oldest recognized vector-transmitted diseases, fraught with a rich historical aspect, particularly as applied to military/wartime situations. The vectors of Orientia tsutsugamushi were once thought to be confined to an area designated as the Tsutsugamushi Triangle. However, recent reports of scrub typhus caused by Orientia species other than O. tsutsugamushi well beyond the limits of the Tsutsugamushi Triangle have triggered concerns about the worldwide presence of scrub typhus. It is not known whether the vectors of O. tsutsugamushi will be the same for the new Orientia species, and this should be a consideration during outbreak/surveillance investigations. Additionally, concerns surrounding the antibiotic resistance of O. tsutsugamushi have led to considerations for the amendment of treatment protocols, and the need for enhanced public health awareness in both the civilian and medical professional communities. In this review, we discuss the history, outbreaks, antibiotic resistance, and burgeoning genomic advances associated with one of the world's oldest recognized vector-borne pathogens, O. tsutsugamushi.

The effects of high dose of two manganese supplements (organic and inorganic) on the rumen microbial ecosystem

Little is known about the effects of the high dose and types of manganese supplements on rumen environment at manganese intake level close above the limit of 150 mg/kg of dry feed matter. The effects of high dose of two manganese supplements (organic and inorganic) on rumen microbial ecosystem after four months of treatment of 18 lambs divided into three treatment groups were studied. We examined the enzyme activities (α-amylase, xylanase, and carboxymethyl cellulase), total and differential microscopic counts of rumen ciliates, total microscopic counts of bacteria, and fingerprinting pattern of the eubacterial and ciliates population analyzed by PCR-DGGE. Lambs were fed a basal diet with a basal Mn content (34.3 mg/kg dry matter; control) and supplemented either with inorganic manganous sulfate or organic Mn-chelate hydrate (daily 182.7, 184 mg/kg dry matter of feed, respectively). Basal diet, offered twice daily, consisted of ground barley and hay (268 and 732 g/kg dry matter per animal and day). The rumens of the lambs harbored ciliates of the genera of Entodinium, Epidinium, Diplodinium, Eudiplodinium, Dasytricha, and Isotricha. No significant differences between treatment groups were observed in the total ciliate number, the number of ciliates at the genus level, as well as the total number of bacteria. Organic Mn did decrease the species richness and diversity of the eubacterial population examined by PCR-DGGE. No effects of type of Mn supplement on the enzyme activities were observed. In comparison to the control, α-amylase specific activities were decreased and carboxymethyl-cellulase specific activities were increased by the Mn supplements. Xylanase activities were not influenced. In conclusion, our results suggested that the intake of tested inorganic and organic manganese supplements in excess may affect the specific groups of eubacteria. More studies on intake of Mn supplements at a level close to the limit can reveal if the changes in microbial population impact remarkably the other rumen enzymatic activities.

Development of SimCells as a novel chassis for functional biosensors

This work serves as a proof-of-concept for bacterially derived SimCells (Simple Cells), which contain the cell machinery from bacteria and designed DNA (or potentially a simplified genome) to instruct the cell to carry out novel, specific tasks. SimCells represent a reprogrammable chassis without a native chromosome, which can host designed DNA to perform defined functions. In this paper, the use of Escherichia coli MC1000 ∆minD minicells as a non-reproducing chassis for SimCells was explored, as demonstrated by their ability to act as sensitive biosensors for small molecules. Highly purified minicells derived from E. coli strains containing gene circuits for biosensing were able to transduce the input signals from several small molecules (glucarate, acrylate and arabinose) into the production of green fluorescent protein (GFP). A mathematical model was developed to fit the experimental data for induction of gene expression in SimCells. The intracellular ATP level was shown to be important for SimCell function. A purification and storage protocol was developed to prepare SimCells which could retain their functions for an extended period of time. This study demonstrates that SimCells are able to perform as ‘smart bioparticles’ controlled by designed gene circuits.

Strategies for detecting rickettsiae and diagnosing rickettsial diseases

Rickettsial diseases and scrub typhus constitute a group of the oldest known vector-borne diseases. The cosmopolitan distribution of the vectors that transmit rickettsiae and orientiae leads to a worldwide prevalence of these diseases. Despite their significant historical status, detection and diagnosis of these diseases are still evolving today. Serological methods remain among the most prevalent techniques used for the detection/diagnosis of rickettsial diseases and scrub typhus. Molecular techniques have been instrumental in increasing the sensitivity/specificity of diagnosis, identifying new Rickettsia and Orientia species and have enhanced epidemiological capabilities when used in combination with serological methods. In this review, we discuss these techniques and their associated pros and cons.

The effect of mechanical stimulation on mineralization in differentiating osteoblasts in collagen-I scaffolds

Developing a viable and functional bone scaffold in vitro that is capable of surviving and bearing mechanical load in vivo requires an understanding of the cell biology of osteoprogenitor cells, particularly how they are influenced by mechanical stimulation during cell differentiation and maturation. In this study, mechanical load was applied using a modified FlexCell plate to impart confined compression to collagen-I scaffolds seeded with undifferentiated murine embryonic stem cells. The activity, presence, and expression of osteoblast-cadherin (OB-Cad) and connexin-43, as well as various pluripotent and osteogenic markers were examined at 5-30 days of differentiation as cells were stimulated to differentiate to osteoblasts with and without applied mechanical load. Fluorescence recovery after photobleaching, immunofluorescence, viability, von Kossa, and real-time polymerase chain reaction assessments revealed that mechanical prestimulation of this cell-seeded scaffold altered the expression of OB-Cad and connexin-43 and resulted in significant differences in the structure and organization of mineralization present in the collagen matrix. Specifically, cells in gels that were loaded for 40 h after 5 days of differentiation and then left to fully differentiate for 30 days produced a highly structured honeycomb-shaped mineralization in the matrix; an outcome that was previously shown to be indicative of late osteoblast/early osteocyte activity. This study highlights the potential of mechanical load to accelerate differentiation and enhance osteoblast communication and function during the differentiation process, and highlights a time point of cell differentiation within this scaffold to apply load in order to most effectively transduce a mechanical signal.

In vitro Antagonism between Cefotaxime and Anti-Rickettsial Antibiotics against Orientia tsutsugamushi

We have investigated the in vitro antimicrobial effects of antibiotic combinations against Orientia tsutsugamushi, the causative agent of scrub typhus. ECV304 cells were infected with the Boryong strain of O. tsutsugamushi and incubated in a medium containing doxycycline (4 µg/mL), azithromycin (0.5 µg/mL), rifampin (4 µg/mL), ciprofloxacin (25 µg/mL), gentamicin (5 µg/mL), cefotaxime (2 µg/mL), or combinations of these agents for 7 days, after which immunofluorescent staining for O. tsutsugamushi was performed. The percentages of infective foci in cultures containing antibiotics compared to those in cultures without antibiotics were 6.2% for doxycycline, 9.6% for azithromycin, 8.8% for rifampin, 96.6% for cefotaxime, 29.7% for doxycycline plus cefotaxime, 23.6% for azithromycin plus cefotaxime, and 41.4% for rifampin plus cefotaxime. These findings show an in vitro antagonism between anti-rickettsial agents and cefotaxime against O. tsutsugamushi. These results suggest that the efficacy of antibiotic combinations involving cefotaxime for the treatment of patients with scrub typhus, particularly those with severe pneumonia, needs to be investigated.

In vitro Synergism between Chloroquine and Antibiotics against Orientia tsutsugamushi

BACKGROUND

To investigate whether chloroquine enhances the effect of antibiotics against Orientia tsutsugamushi, the causative organism of scrub typhus, we compared the effect of antibiotics in combination with chloroquine with the effect of antibiotics alone in vitro.

MATERIALS AND METHODS

The Boryong or AFSC-4 strain was inoculated into ECV304 cells, and incubated in medium containing doxycycline (4 µg/mL), rifampin (4 µg/mL), azithromycin (0.5 µg/mL), chloroquine (1 µg/mL), and each of these antibiotics in combination with chloroquine for 7 d. Immunofluorescence (IF) staining for O. tsutsugamushi was performed 4 hr and 7 d after inoculation of the bacteria, and IF-positive foci were enumerated.

RESULTS

Chloroquine inhibited the growth of O. tsutsugamushi by 15.5%. In combination with chloroquine, the antimicrobial effects increased by 4.4% for doxycycline (a 92.9% reduction of bacterial numbers for doxycycline versus a 97.3% reduction for doxycycline plus chloroquine), 4.6% for rifampin (90.0% versus 94.6%), and 8.3% for azithromycin (86.9% versus 95.2%). The antimicrobial effect of the antibiotics alone was significantly different compared to the combined effect of antibiotics and chloroquine (Wilcoxon signed-rank test, P = 0.001).

CONCLUSIONS

The combined use of chloroquine with an antibiotic for the treatment of O. tsutsugamushi infections may be useful for increasing the efficacy of the antibiotics.