The periodicity in the consumption of oxygen in Asellus aquaticus [Translation from: Vestnik ceskoslovenske zoologicke Spolecnosti, 15, 1, 89-97, 1951]

The consumption of oxygen in Asellus aquaticus was measured to find if there existed a periodicity in the consumption of oxygen and how this showed itself during the course of the day, year and in various experimental conditions. From the figures obtained comparative values were calculated and from these curves were plotted of the changes in the consumption of oxygen during the day and year

I Know

A story inspired by my memories

Multi-omics of AML

Acute myeloid leukemia (AML) is one of the most aggressive hematopoietic malignancies and has been recognized as a heterogeneous disease due to a lack of unifying characteristics. It is driven by different genome aberrations, gene expression changes, and epigenomic dysregulations. Therefore a multi-omics approach is needed to unravel the complex biology of this disease. This thesis deals with the challenges of identifying driver events that account for differences in clinical phenotypes and responses to treatment. The work presented here investigates the driver events of AML and epigenetics drug response profiles. The thesis consists of three main projects. The first study identifies recurrent mutations in AML carrying t(8;16)(p11;p13), a rare abnormality. The second project is identifying prospective drivers of mutation- negative nkAML. The third project concentrates on epigenetic changes after AML drugs. t(8;16) AML is a rare and distinguishable clinicopathological entity. Some previous reports that rep- resented the characteristics of patients with this type of AML suggest that the t(8;16) translocation could be sufficient to induce hematopoietic cell transformation to AML without acquiring other genetic alterations. Therefore here I evaluate the frequently mutated genes and compare them with the most frequent mutated genes in AML in general and AML carrying t(8;16) translocation. FLT3 mutation was found in 3 patients of my cohort, a potential target for therapy with tyrosine kinase inhibitors. However, exciting finding was the mutations in EYS, KRTAP9-1, PSIP1, and SPTBN5 that were depicted earlier in AML. Elucidating different layers of aberrations in normal karyotype no-driver acute myeloid leukemia pro- vides better biology insight and may impact risk-group stratification and new potential driver events. Therefore, this study aimed to detect such anomalies in samples without known driver genetic abnor- malities using multi-omic molecular profiling. Samples were analyzed using RNA sequencing (n=43), whole genome sequencing (n=43), and EPIC DNA methylation array (n=42). In 33 of 43 patients, all three layers of data were available. I developed a pipeline looking for a driver in any layer of data by connecting the information of all layers of data and utilizing public genomic, transcriptomic, and clinical data available from TCGA. Genetic alterations of somatic cells can drive malignant clone formation and promote leukemogenesis. Therefore I first built a mutation prioritization workflow that checks each patient’s genomic mutation drivers. Here I use the information on the allele frequency of the specific mu- tation combining information from WGS and RNA sequencing data. Finally, I compared each mutation on a positional level with AML and other TCGA cancer cohorts to assess the causative genomic muta- tions. I found potential driver stopgain mutation in genes implicated in chromosome segregation during mitosis and some tumor suppressor genes. I found new stopgain mutations in cancer genes (NIPBL and NF1). Since fusions are increasingly acknowledged as oncology therapeutic targets, I investigated potential driver fusion events by evaluating high-confidence and in-frame cancer-related fusion findings. As a result, I found specific gene fusion patterns. Kinases activated by gene fusions define a meaningful class of oncogenes associated with hematopoietic malignancies. I identify several novel and recurrent fusions involving kinases that potentially play a role in leukemogenesis. I detected previously unreported fusions involving known cancer-related genes, such as PIM3- RAC2 and PROK2- EIF4E3. In addition, outliers, such as gene expression levels, can pinpoint potential pathogenic events. Therefore, combining my AML cohort with a healthy control group, I determined aberrant gene expression levels as possible pathogenic events using the deep learning method. Finally, I combined the data and looked for a com- parison to the methylation pattern of each patient. Overall, the analysis uncovered a rich landscape of potential drivers. In different data layers, I found an altered genomic and transcriptomic signature of different GTPases, which are known to be involved in many stages of tumorigenesis. My methods and results demonstrate the power of integrating multi-omics data to study complex driver alterations in AML and point to future directions of research that aim to bridge gaps in research and clinical applications. Furthermore, I provide in vitro evidence for antileukemic cooperativity and epigenetic activity between DAC and ATRA. I performed differential methylation analysis on CpG resolution and across genomic and transposable elements regions, enhancing the results’ statistical power and interpretabil- ity. I demonstrated that single-agent ATRA caused no global demethylation, nor did ATRA improve the demethylation mediated by DAC. In summary, combining multi-omics profiling is a powerful tool for studying dysregulated patterns in AML. Furthermore, multi-omics profiling performed on mutation- negative nkAML reveals several promising drivers. My findings not only go beyond augmenting my understanding of the heterogeneity landscape of AML but also may have immediate implications for new targeted therapy studies

Using three-dimensional digital models to establish alveolar morphotype

Background: The aim of the study was to propose a classification of alveolar morphotype and assess a relationship between extraction/non-extraction orthodontic treatment and changes to the alveolar process.Materials and methods: Seventy-five subjects (mean age = 23.2, SD = 5.1) were selected. Areas of the sections of the alveolar process (ASAP) at three different levels (0, 2, and 4 mm) were measured on pre- and post-treatment three-dimensional digital models. Method reliability was analysed using Dahlberg’s formula, intraclass correlation coefficient, and paired t-tests.Results: The mean ASAP was smallest at level 0 and largest at level 4. Pre-treatment ASAP < 773 mm2, < 863.9 mm2, and < 881.1 mm2 at levels 0, 2, and 4 mm, respectively, should be described as a “thin” alveolar morphotype. Regression models showed that pre-treatment ASAP was a predictor of the change of the alveolus during treatment only at level 2.Conclusions: Patients for whom pre-treatment ASAP is < 773 mm2, < 863.9 mm2, and < 881.1 mm2 at levels 0, 2, and 4 mm, respectively, should be described as having a “thin” alveolar morphotype. In these patients, extraction treatment, associated with a decrease in the alveolus area, should be exercised with caution

Targeted Doxorubicin Delivery to Brain Tumors via Minicells: Proof of Principle Using Dogs with Spontaneously Occurring Tumors as a Model

BACKGROUND: Cytotoxic chemotherapy can be very effective for the treatment of cancer but toxicity on normal tissues often limits patient tolerance and often causes long-term adverse effects. The objective of this study was to assist in the preclinical development of using modified, non-living bacterially-derived minicells to deliver the potent chemotherapeutic doxorubicin via epidermal growth factor receptor (EGFR) targeting. Specifically, this study sought to evaluate the safety and efficacy of EGFR targeted, doxorubicin loaded minicells (designated EGFRminicellsDox) to deliver doxorubicin to spontaneous brain tumors in 17 companion dogs; a comparative oncology model of human brain cancers. METHODOLOGY/PRINCIPLE FINDINGS: EGFRminicellsDox were administered weekly via intravenous injection to 17 dogs with late-stage brain cancers. Biodistribution was assessed using single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI). Anti-tumor response was determined using MRI, and blood samples were subject to toxicology (hematology, biochemistry) and inflammatory marker analysis. Targeted, doxorubicin-loaded minicells rapidly localized to the core of brain tumors. Complete resolution or marked tumor regression (>90% reduction in tumor volume) were observed in 23.53% of the cohort, with lasting anti-tumor responses characterized by remission in three dogs for more than two years. The median overall survival was 264 days (range 49 to 973). No adverse clinical, hematological or biochemical effects were observed with repeated administration of EGFRminicellsDox (30 to 98 doses administered in 10 of the 17 dogs). CONCLUSIONS/SIGNIFICANCE: Targeted minicells loaded with doxorubicin were safely administered to dogs with late stage brain cancer and clinical activity was observed. These findings demonstrate the strong potential for clinical applications of targeted, doxorubicin-loaded minicells for the effective treatment of patients with brain cancer. On this basis, we have designed a Phase 1 clinical study of EGFR-targeted, doxorubicin-loaded minicells for effective treatment of human patients with recurrent glioblastoma

Prognostic Value of Hepatocyte Growth Factor, Syndecan-1, and Osteopontin in Multiple Myeloma and Monoclonal Gammopathy of Undetermined Significance

Our aim was to compare serum levels of selected biological parameters in different phases of multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS) to determine their diagnostic and prognostic potential. A cohort of 234 individuals was assessed for serum levels of hepatocyte growth factor (HGF), syndecan-1/CD138 (SYN), and osteopontin (OPN). The patients with MM (N = 156) were divided into 3 groups: at the time of diagnosis (N = 45), in relapse/progression (N = 56), and in remission (N = 50). The analysis revealed significant differences of all three parameters in comparison of active and remission phase MM. Moreover, the parameters in active myeloma were significantly higher than in MGUS. Within the comparison of active disease (newly diagnosed and relapsing), there was no significant difference. Similar results were in remission phase MM and MGUS. There was no relationship of pretreatment levels of the parameters to therapeutic response. We conclude that serum levels of HGF, OPN, and SYN correspond to the activity of MM and might become useful in differentiation of MGUS, asymptomatic MM, and overt/symptomatic form of MM. The levels of all three parameters behave accordingly with MM activity. Pretreatment measurement without the assessment of their kinetics, however, has no relationship to therapeutic response

Thymic squamous cell carcinoma in a cat

Background: The most common cranial mediastinal masses affecting dogs and cats include lymphoma and thymic epithelial tumors. In this report, a cat with a cranial mediastinal mass was diagnosed with a thymic carcinoma subtype squamous cell carcinoma, which has rarely been reported in cats. Management of this subtype with a combination of surgery and chemotherapy has so far not been reported. This case report describes the treatment with surgical management followed by intracavitary carboplatin. Case Description: A 12-year-old male neutered domestic short hair cat was referred for lethargy, hyporexia, and weight loss, and was diagnosed with a cranial mediastinal mass radiographically. Initial cytology through fine needle aspirates was suggestive of carcinoma. Computed tomography was performed which did not show evidence of other primary tumor sources or metastases, and hence surgical resection was recommended. Intraoperative findings revealed local invasion of the surrounding tissues, including major vasculature and nerves, although histopathological assessment showed no local lymph node involvement. Intracavitary carboplatin chemotherapy was administered 2 weeks postsurgery. The patient was humanely euthanized 4 weeks postsurgery due to evidence of local recurrence causing significant respiratory compromise. Conclusion: A combination of surgical excision as well as intracavitary carboplatin does not seem to be effective for the treatment of this thymic carcinoma subtype, with evidence of early recurrence and return of clinical signs

Evaluation of hoof horn quality by tensile test and hardness test using acoustic emission

The research aimed to explore the use of tensile tests and hardness tests in combination with acoustic emission to evaluate the physical properties of hoof horn quality in dairy cows. Lameness is a significant issue in dairy farms worldwide, with a prevalence ranging from 14-31%. Reducing its occurrence is essential to minimize economic losses in farms. Lameness can cause production, reproduction, and welfare problems, leading to high costs of hoof treatment, lower milk production, and premature culling of animals from breeding. Even small changes in breeding management, nutrition, or technology can disrupt the formation of keratin and lead to changes in the horn. Evaluating the mechanical properties of the horn could be one of the tools to control the quality of the horn and prevent animal lameness. The goal of the experiment was to record the acoustic emission when the material broke and investigate the differences in the physical properties of the biological material. Both tests found high variability in sample resistance and acoustic signals depending on the sampling location. Samples taken from the hoof wall showed greater hardness, while samples taken from the heel were more elastic. These parameters and possible differences could be used to evaluate horn quality, which plays a fundamental role in the development of hoof disease and lameness

Analysis of Snail-1, E-Cadherin and Claudin-1 Expression in Colorectal Adenomas and Carcinomas

We report the expression of Snail-1, E-cadherin and claudin-1 by indirect immunohistochemistry in colonic neoplasia. Snail-1 is a zinc finger transcription factor expressed in cells that already have undergone almost complete epithelial-mesenchymal transition (EMT) and have already evaded from the tumor. The main mechanism by which Snail induces EMT is downregulation of E-cadherin, of which expression was shown to be frequently downregulated in many different types of tumors, where it accompanies the invasiveness and metastatic behavior of malignant cells. Moreover, Snail-1 may downregulate the expression of claudin-1, a cell-cell adhesion protein which plays a likely role in progression and dissemination during tumorigenesis. Snail-1 was expressed in both carcinoma and adenoma cells with histologically normal epithelium in the mucosa, adjacent to the tumors, without significant differences, and predominant strong intensity of staining. Statistically significant differences were revealed between normal and tumorous epithelium (p = 0.003) at the subcellular level, where the shift of the protein to the cytoplasm with combined cytoplasmic/nuclear or pure cytoplasmic expression was observed. E-cadherin expression was present in 100% of cases of both adenocarcinomas and adenomas, with prevailing strong membranous immunoreactivity and no differences between protein expression in tumors and normal mucosa. Predominating strong positivity of claudin-1 was detected in tumor cells of adenocarcinomas and adenomas. Marked differences were seen in protein localization, where membranous staining, typical for nontumorous epithelium, changed to combined membranous/cytoplasmic expression in adenocarcinomas (p = 0.0001) and adenomas (0.0002), in which cytoplasmic shift was associated with a higher degree of dysplasia. Furthermore, membranous/cytoplasmic localization was more frequent in the carcinoma group (87%) in comparison with adenomas (51%) (p = 0.0001). We conclude that dystopic subcellular localizations of Snail-1 and claudin-1 may participate in changes of cellular morphology and behavior which might be associated with altered effectory pathways of proteins and thus substantially contribute to the cancer development