Using FCS to Explore Agglomeration States of Small Heat Shock Proteins

Small heat shock proteins are present in nearly every form of life. However, despite their ubiquity, there are many questions about the structure of sHSPs. It is known that they can take a monomeric or an oligomeric form, and they have chaperone-like properties, meaning they help protect and fold other proteins. The aggregation and separation of these oligomers are reversible and controlled by environmental factors such as temperature and pH, but there are questions about the specifics of this process. I am growing up, purifying, and labeling sHSP so I can look into these questions using fluorescence correlation spectroscopy

Using Pre-Cleaned Coverslips to Optimize Coverslip Preparation for Single-Molecule Fluorescence Microscopy

Single-molecule fluorescence microscopy has become a popular tool for exploring structural changes and dynamics of biological systems. In our laboratory, we use single-molecule techniques to track conformational changes of immobilized nitric oxide synthase (NOS) and determine their relationship to catalytic activity. Properly immobilizing biomolecules like NOS on a glass surface requires careful attention to coverslip cleaning and preparation. There are many protocols available for cleaning glass coverslips, but these protocols are time-consuming and often use harsh conditions. Alternatively, commercially cleaned and passivated coverslips are available but are quite expensive. In this poster, we examine the possibility of using purchased pre-cleaned coverslips (Schott Nexterion) that come ready to be prepared for single-molecule measurements. We present figures and measurements of merit comparing the pre-cleaned coverslips with ozone cleaned coverslips; demonstrating the effectiveness of pre-cleaned coverslips for single-molecule fluorescence microscopy

Electron microscopic observation in case of platelet activation in a chronic haemodialysis subject

During haemodialysis (HD), platelets (PLTs) are activated and release granule contents. As HD treatment occurs three times a week, it has been demonstrated that PLTs are exhausted due to the repetitive character of the treatment. To identify PLT depletion morphologically, PLT evaluation was performed by light microscopy and electron microscopy (EM) in a chronic HD subject and a healthy reference subject. Blood samples were taken before the start of HD treatment for measurement of PLT count, PLT volume and size parameters. Blood smears were screened by light microscopy for qualitative evaluation of PLT granule containing cytoplasm, as indicated by its staining density. Morphological PLT parameters of surface area and size of dense bodies were assessed by EM. Data were compared with results of a group of 20 chronic HD subjects and a group of 20 healthy reference subjects. With respect to the percentage of PLTs with appropriate staining density (>75%), light microscopic evaluation showed that this value (9%) was within the range of a group of chronic HD subjects, but considerably below the reference range (70%). EM evaluation revealed an average PLT surface area and dense bodies area of respectively 42% and 31%, if the healthy reference subject was set on 100%. PLTs from a chronic HD subject are considerably smaller and substantially less granular than PLTs from a healthy reference subject. These findings support the hypothesis of PLT depletion in chronic HD subjects due to frequent PLT activation and/or increased urea concentrations

Short mucin 6 alleles are associated with H pylori infection

Contains fulltext : 49314.pdf (publisher's version ) (Open Access)AIM: To investigate the relationship between mucin 6 (MUC6) VNTR length and H pylori infection. METHODS: Blood samples were collected from patients visiting the Can Tho General Hospital for upper gastrointestinal endoscopy. DNA was isolated from whole blood, the repeated section was cut out using a restriction enzyme (Pvu II) and the length of the allele fragments was determined by Southern blotting. H pylori infection was diagnosed by (14)C urea breath test. For analysis, MUC6 allele fragment length was dichotomized as being either long (> 13.5 kbp) or short (< or = 13.5 kbp) and patients were classified according to genotype [long-long (LL), long-short (LS), short-short (SS)]. RESULTS: 160 patients were studied (mean age 43 years, 36% were males, 58% H pylori positive). MUC6 Pvu II-restricted allele fragment lengths ranged from 7 to 19 kbp. Of the patients with the LL, LS, SS MUC6 genotype, 43% (24/56), 57% (25/58) and 76% (11/46) were infected with H pylori, respectively (P = 0.003). CONCLUSION: Short MUC6 alleles are associated with H pylori infection

Elucidating Antiproliferative Mechanisms of Grapeseed, Guava, and Juniper Berry Extracts

Plant extracts are an untapped source of medicinal potential. Even today they are used as standalone treatments and applied alongside conventional therapies. The focus of our laboratory is to identify plant extracts exhibiting antiproliferative activity in vitro, to determine which chemicals are responsible for this activity, and to elucidate mechanism(s) by which growth is slowed/inhibited by plant extracts. Specifically, we exposed five cell lines/strains to twenty-two plant extracts and measured cell proliferation. Extracts from Vinca, Juniper Berry, Guava, Grapeseed, and Yew slowed the growth of all five lines/strains in a dose dependent fashion. We are working to understand the mechanism of antiproliferation by measuring induction of apoptosis, effects on microtubule assembly, and wound healing

Holding time study of volatile organic compounds in SUMMA canisters

According to this work, the headspace concentration of VOC`s is not changing measurably with time. That is, no appreciable uncertainty is added to the analysis of VOC`s in the headspace of storage drums by storage of the samples in SUMMA canisters for greater than 28 days

Increased FDG avidity in lymphoid tissue associated with response to combined immune checkpoint blockade

BACKGROUND: Antibodies against programmed death 1 (PD-1) receptor and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) have transformed the systemic treatment of melanoma and many other cancers. Understanding the spectrum of benign findings and atypical response patterns seen in immune checkpoint blockade is important for accurately assessing treatment response as these immunotherapies become more widely used. CASE PRESENTATION: We report a 63-year-old man with metastatic melanoma successfully treated with combination CTLA-4 and PD-1 blockade (ipilimumab and nivolumab), after non-response to pembrolizumab monotherapy. The initial impression of disease progression, based on cutaneous and PET/CT findings of increased fluoro-2-deoxy-D-glucose (FDG) uptake in benign lymphoid tissue, proved to be erroneous after assiduous review of radiographic imaging and correlative pathology. CONCLUSIONS: These findings indicate that increased FDG uptake in benign lymphoid tissue seen on PET/CT may be a surrogate marker of immune activation and treatment response. Prospective studies will be invaluable in validating immune-related radiographic findings as a prognostic biomarker of response in cancer patients being treated with immune checkpoint blockade

Regional 2-[ 18 F]fluoro-2-deoxy- d -glucose uptake varies in normal lung

2-[ 18 F]fluoro-2-deoxy- d -glucose positron emission tomography (FDG-PET) is a promising imaging procedure for detecting primary and metastatic cancer in the lungs. We have, however, failed to detect some small tumors in the lower lobes of the lungs. This study aimed to determine whether increase 18 F background activity in the dependent lower lungs is present, which could make lesion detection more difficult. We measured the standardized uptake values (SUVs) for FDG of normal lung remote from the nodular lesion in 16 patients with newly diagnosed untreated lung lesions stronlgy suspected to represent non-small cell lung cancers. In addition, 15 patients with known or suspected primary breast cancers without pulmonary lesions were included as control subjects. After PET transmission images of the thorax were obtained, approximately 370 MBq of FDG was injected intravenously and imaging was immediately begun. Patients were supine throughout the study. SUVs were determined with images obtained 50–70 min after FDG injection. Regions of interest (ROls) of 6×6 pixels were positioned over normal lung in anterior, mid, and posterior portions of upper, middle, and lower lung fields. Thus, as many as 18 ROls were positioned in each patient. The SUVs of the posterior portion were significantly higher than those of the anterior and mid portions in the population of 31 cases ( P <0.001). Also, the mean SUV of the lower lung field was significantly higher than the SUVs of the upper and middle lung fields in this population ( P <0.01). This pattern was seen among the two groups of 16 patients suspected of having lung cancer and 15 control subjects. Background 18 F activity was highest in posterior and lower lung in these patients. The maximum value of mean SUV observed in normal posterior lower lung was 0.804±0.230 (41% greater than the mean SUV in the anterior upper lung), which is in the range of the apparent SUV for a 5-mm lung lesion, with higher SUV, due to recovery coefficient issues. Thus this phenomenon could contribute to occasional false-negative lesions in those areas. Increased blood flow and FDG delivery and also scatter from heart and liver may contribute to the increased lower lung background activity. Regional differences in normal lung FDG uptake are significant and should be considered when interpreting pulmonary PET studies in patients with suspected primary or metastatic lung cancer.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46841/1/259_2004_Article_BF00833385.pd