Frozen section diagnosis (FSD) is a method implemented within the field of clinical histopathology and is used primarily intraoperatively to guide the surgical team, with regard to, for example, the severity and spread of the affliction. However, medical professionals typically refrain from relying on FSD due to the poor morphological outcome when compared to paraffin sectioning. There are several contributing factors for the lesser quality of FSD sections with one being the type of tissue evaluated and a prominent example of this is lung tissue.Optimizing the quality of sections obtained from FSD could provide more accurate diagnoses for patients.This thesis aims to assess various parameters related to FSD procedures to improve the morphological outcome. Comparisons between no injection and the injection of different solutions pre-freezing were made. Additionally, two different methods that are referred to as freehand- and tape-sectioning were compared. The results of the injections indicate that using O.C.T improves both the architecture of the tissue as well as the morphology. For practical reasons, O.C.T diluted 1:1 with saline was determined to be the best alternative to use in a clinical laboratory. When comparing the different sectioning methods, the Cryo-Jane tape transfer system produced a better section quality in the cases with injected O.C.T. Freehand sectioning did produce better results regarding connective tissue as well as cytoplasm. This means that depending on what parameters are deemed most important by the pathologist both methods have their distinct advantages.

Introduction: Chronic Achilles Tendinopathy (CAT) is a common sports injury that affects a substantial portion of the population. One of the clinical treatments of CAT is ultrasound guided sclerosis (UGS), the efficacy of which is both supported and contested in a numberof previous reports.  Aim: The aim of the study was to assess current and former CAT diagnosed patients’ experiences of stiffness, pain and function of the Achilles tendon (AT) before and after UGS, in order to determine the treatment efficacy. Methods: A retrospective study based on a modified Victorian Institute of Sports Assessment – Achilles – Survey (VISA-A-S). VISA-A-S questionnaire, with 123 study participants, allof whom were treated at Uppsala University Hospital between 2016-2020 and who had experienced stiffness, pain, and dysfunction of AT before and after UGS. Statistical analysis was performed Wilcoxon Signed-Rank tests. Results: The response rate to the survey questionnaire was 62%. In total, 80% of all study participants reported that they were satisfied with the treatment. After UGS, 74% reported shorter period of morning stiffness, 85% had less pain and 84% experienced improved function, as compared to before the treatment (P<0.0001 for all). Conclusion: The results of this study were both statistically and clinically significant. Based on the results of this retrospective study, it is reasonable to conclude that UGS is an effective clinical procedure in treating CAT. This means that this study confirms conclusions of a part of previous studies on the effectiveness of the UGS treatment, which had indicated that UGS is an effective treatment of CAT.

Neuroendocrine tumors (NET) are an unusual form of cancer that can occur in many different organs, commonly in the small intestinal. NET can be detected with the help of immunohistochemistry (IHC). IHC uses antibodies that bind to an antigen in the tissue. NET can be studied through this bond, which forms a colored product during an enzyme reaction, using a chromogenic or fluorescence-based method. Usually, NETs are analyzed with synaptophysin, chromogranin A, and CD56 markers. Novel studies have been conducted on insulin-associated protein 1(INSM1), a new emerging NET marker suggested to have higher specificity and sensitivity than the markers mentioned above.   The work aimed to investigate the optimal protocol for INSM1, test an appropriate control, and evaluate if the INSM1 antibody works according to the description in the scientific literature and is suitable to be introduced into the routine practice and used as a diagnostic marker at the department for pathology and cytology in Växjö.  The evaluation of INSM1 was performed on sectioned tissue samples with NET. NET staining was evaluated by dilution of the INSM1 antibody, different pretreatments and visualizing kits were used. The staining’s of INSM1 were assessed microscopically together with a pathologist.   The analysis showed that the optimal result was gained by using 1 mg/ml of the INSM1 antibody. The staining intensity was preferable using the OptiView compared to UltraView. The INSM1-antibodies showed better binding to the antigen when using the “standard” pretreatment and the color intensity was more intense compared to the “mild” pretreatment. The evaluation showed that OptiView and standard pretreatment, gave the optimal result for NET diagnostics using the INSM1 antibody. Based on the work herein, the antibody INSM1 could be introduced into the routine practice at the department of pathology and cytology in Växjö.

The current study utilized laboratory tasks (Conners' Continuous Performance Test, CPT; Behavioral Inhibition Task, BIT) to examine the relationships among motivation, executive functioning, and parent and teacher-reported attention, internalizing, and externalizing problems in a clinical sample of 132 children with or without Attention-Deficit/Hyperactivity Disorder, Combined Type (ADHD-C; 69% male, mean age = 9.88). Specificity was examined through total, unique, and interactive effects via hierarchical regression. Higher CPT scores (i.e., executive disinhibition) were related to greater externalizing problems in total and unique effect analyses, while a relationship between lower CPT scores (i.e., executive inhibition) and greater internalizing problems was found only in unique effect analyses. No significant effects were found for motivational inhibition (i.e., low BIT) or disinhibition (i.e., high BIT). ADHD-C was associated with greater attention and externalizing problems in total effect analyses, but only externalizing problems showed a significant relationship in unique effect analyses. Interactive effects were found for ADHD-C and executive functioning, as lower levels of CPT (i.e., executive inhibition) coupled with ADHD-C resulted in greater parent-reported attention problems. In addition, higher CPT scores (i.e., executive disinhibition) were associated with greater parent-reported externalizing problems in Non-ADHD-C children. Although some main effects were predicted, the interactive effects were somewhat surprising, particularly in relation to ADHD-C, executive inhibition, and parent-reported attention problems. Exploratory analyses revealed that this effect may have been due to greater internalizing problems in ADHD-C children at lower levels of CPT (i.e., executive inhibition). Results are discussed in relation to past studies and laboratory task validity. / Master of Science

With the rapidly increasing importance placed by industry upon the development, treatment, examination and testing of metals and their alloys, there follows increasing stress on sound fundamentale in metallurgical laboratory practice as employed by the student majoring in this field. Following a study of the requirements which must usually be met by the graduate who intends to continue his work in metallurgy, a series of experiments has been carefully planned, performed, and thoroughly studied to determine their value to the student. This work was done under the direction and direct supervision of Professor H. V. White, Head of the Department of Metallurgical Engineering of Virginia Polytechnic Institute, and with the facilities of the laboratory under his charge. General instructions in the selected experiments and typical laboratory reports are contained in the pages which follow. Since a large part of the experimental work was done with laboratory equipment developed for these specific experiments, description of apparatus and certain explanations are included in Section II, Experiment Reports. / Master of Science

Stem cell niches serve as vital reservoirs, maintaining stem cells in a dormant state through specific niche components. Various biomarkers associated with stem cell niches have been identified in different tissues, including cardiac tissue, particularly at the atrioventricular junction. This study collected mouse, donor, and explanted cardiac tissue from the right side of the heart, focusing on the atrioventricular junction. Additionally, left ventricle samples from donor hearts were harvested. All samples were examined via immunohistochemistry to detect niche-related biomarkers. The study aimed to validate the atrioventricular junction as a potential niche area and to explore Cathepsin K asa possible cardiac stem cell marker, noting its slight nuclear expression. Clear expression of the stemcell marker SSEA4, the hypoxia marker Hif-1α, and the extracellular matrix marker ACAN, along with weak expression of the extracellular matrix marker CILP2, was observed, alongside Cathepsin K. Notably, explanted cardiac samples exhibited lower marker expression, except for Hif-1α, suggesting reduced oxygen levels in failing hearts. Mouse samples displayed the highest expression for each marker, mirroring the distribution seen in human hearts. Although the study does not conclusively validate the existence of a cardiac stem cell niche or the role of Cathepsin K, its findings significantly advance niche research. Further investigation is warranted to elucidate the role of the atrioventricular junction and associated biomarkers in cardiac stem cell biology.

Liver Cancer, especially hepatocellular carcinoma is a major global health challenge with increasing occurrence and mortality rates. This study aimed to explore and understand the molecular signature of the disease using bioinformatic analysis with The Cancer Genome Atlas Liver Hepatocellular Carcinoma dataset to identify differentially expressed genes and somatic mutations associated with patient survival. Transcriptome analysis revealed a significant difference in gene expression between tumor and normal tissues. Survival analysis linked specific genes to patient outcomes which suggests potential prognostic markers further proved by clinical enrichment analysis using Metascape, an online platform. Single nucleotide variant analysis uncovered frequently mutated genes, including TP53, CTNNB1, and TTN, and characterized the mutation landscape, revealing prevalent C>T transitions. The integration of transcriptome and mutation data complements potential therapeutic targets and driver mutations which are important for the liver cancer development and progression. Overall this study provides valuable insights and is a framework into the molecular mechanisms of HCC and identifies potential DEGs, biomarkers (FCN2, FCN3, and COLEC10), and clinically actionable targets for improved diagnosis and therapeutic strategies.

Avian influenza, known as bird flu, is a highly contagious acute respiratory infection that infects many avian species, humans and other animals. Birds infected with Influenza A virus can shed large amounts of virus in feces, which can be detected in the lakes. Similarly, people infected with enteric viruses also shed high amounts of virus in their feces, which can end up in lake water. In this study, the presence of influenza A and seven enteric viruses (norovirus GII, astrovirus, enterovirus, adenovirus, sapovirus, hepatitis E virus, and pepper mild mottle virus) were investigated in recreational lakes to explore whether their identification could be used as an early warning of outbreaks. Lake water samples were collected from Axlemossen, Delsjön, Slottsskogen, and Torpadammen. The samples were taken monthly from November 2023 until April 2024 and analyzed for detection of viruses by concentration through ultrafiltration and quantitative polymerase chain reaction. Influenza A virus was selectively detected in the urban lakes of Slottsskogen and Torpadammen, where favorable pH, temperature, and high bird populations likely supported the virus's stability in the lakes. In contrast, enteric viruses showed a broader distribution across all lakes, likely driven by human fecal contamination from recreational activities or possibly from untreated wastewater discharges from unknown sources. The method used in this study aids in studying the presence and behavior of circulating strains in birds. Additionally, it can help understand the potential public health risks of waterborne viruses, especially those transmitted through avian or human fecal matter in the local environment.

The zone of Ranvier has been identified as a stem cell niche located directly next to the epiphyseal growth plate in the knee structure, which has drawn attention as a potential area of study in stem cell therapy treatments for degenerative cartilage diseases, such as osteoarthritis. Cathepsin K, a cysteine protease, is a stem cell marker used to identify stem cells and the niches they reside in. This research aims to analyse Cathepsin K expression in the zone of Ranvier in 10 day postnatal mice, as well as zebrafish of three ages (3 and 5 days post fertilisation, and adult). Staining through immunohistochemistry, and imaging with fluorescent microscopy were the methods chosen to visualise the expression of each marker as they allow a preservation of the structural integrity of the sample. The images showed a nuclear expression of Cathepsin K in the zone of Ranvier. Meanwhile in zebrafish, it was concentrated in both nuclei and the extracellular matrix of jaw bones. There were no compelling differences in the expression between the developmental stages. The counterstaining performed with known stem cell niche markers helped identify both the location of the stem cell niches where Cathepsin K would be expected and the differences of expression between murine and fish tissues. The findings of this research showed Cathepsin K as one of the markers expressed in the zone of Ranvier, which gives further insight into this stem cell niche and its possible use in the treatment of osteoarthritis and other cartilage degenerative diseases.

The gut microbiota, comprised of a plethora of bacterial species, is a crucial part of the digestive system. The intestinal flora regulates many physiological processes and contributes to a large proportion of an individual's daily energy production. Certain bacteria phyla that reside in the mucus layer of the large intestine play an important role in our physiology. Gut bacteria are capable of processing complex fibres that are present in our diet, influencing organ function, and modulating the immune system. Even slight changes in the microbiota’s composition result in several pathologies. Bacteroides species are known for their ability to metabolize carbohydrates and have acquired interesting mechanisms of processing O- and N-glycosylated proteins, with the latter being the focus of this study. This experiment aims to elucidate the degrading mechanisms of N-glycosylated proteins by Bacteroides species, differentiate between the main degrader species, and analyse the extent of this degradation. Out of all the bacteria strains tested, Bacteroides fragilis and Bacteroides massiliensis displayed proteolytic activity on fetuin, which was further verified through Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) and thin-layer chromatography (TLC) analyses. Additionally, six B.fragilis proteins from the GH18 family were cloned and tested for enzymatic activity on various substrates, however, no activity was observed. This work established the phenotypes of bacterial N-glycan degradation.