146 research outputs found

    Organization of Block Copolymers using NanoImprint Lithography: Comparison of Theory and Experiments

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    We present NanoImprint lithography experiments and modeling of thin films of block copolymers (BCP). The NanoImprint lithography is used to align perpendicularly lamellar phases, over distances much larger than the natural lamellar periodicity. The modeling relies on self-consistent field calculations done in two- and three-dimensions. We get a good agreement with the NanoImprint lithography setups. We find that, at thermodynamical equilibrium, the ordered BCP lamellae are much better aligned than when the films are deposited on uniform planar surfaces

    Block Copolymer at Nano-Patterned Surfaces

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    We present numerical calculations of lamellar phases of block copolymers at patterned surfaces. We model symmetric di-block copolymer films forming lamellar phases and the effect of geometrical and chemical surface patterning on the alignment and orientation of lamellar phases. The calculations are done within self-consistent field theory (SCFT), where the semi-implicit relaxation scheme is used to solve the diffusion equation. Two specific set-ups, motivated by recent experiments, are investigated. In the first, the film is placed on top of a surface imprinted with long chemical stripes. The stripes interact more favorably with one of the two blocks and induce a perpendicular orientation in a large range of system parameters. However, the system is found to be sensitive to its initial conditions, and sometimes gets trapped into a metastable mixed state composed of domains in parallel and perpendicular orientations. In a second set-up, we study the film structure and orientation when it is pressed against a hard grooved mold. The mold surface prefers one of the two components and this set-up is found to be superior for inducing a perfect perpendicular lamellar orientation for a wide range of system parameters

    Significance of signet ring cells in high-grade mucinous adenocarcinoma of the peritoneum from appendiceal origin

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    Significance of signet ring cells in mucinous adenocarcinoma of the peritoneum from appendiceal origin has never been specifically studied. We retrospectively reviewed cases of mucinous adenocarcinoma of the peritoneum from appendiceal origin (n = 55) and collected clinical follow-up data. Signet ring cells were identified in 29 of 55 cases. No low-grade mucinous adenocarcinoma case (n = 11) had signet ring cells, whereas 29 of 44 high-grade mucinous adenocarcinoma cases did. Cases of high-grade mucinous adenocarcinoma were subdivided into 3 groups: (1) high-grade mucinous adenocarcinoma without signet ring cells (n = 15), (2) high-grade mucinous adenocarcinoma with signet ring cells only within mucin pools (n = 20), and (3) high-grade mucinous adenocarcinoma with signet ring cells invading tissue (n = 9). Overall survival (OS) and progression-free survival were subsequently evaluated. Five-year OS for cases of high-grade mucinous adenocarcinoma without signet ring cells and high-grade mucinous adenocarcinoma with signet ring cells within mucin pools were similar at 31.8% (SE, 14.4%) and 35.8% (SE, 13.9%), respectively. A significant survival difference was seen for cases of high-grade mucinous adenocarcinoma with signet ring cells invading tissue with a median OS of 0.5 years versus 2.9 and 2.4 years (P = .04 and P = .03), respectively, for cases of high-grade mucinous adenocarcinoma without signet ring cells and high-grade mucinous adenocarcinoma with signet ring cells within mucin pools. Finding signet ring cells floating in extracellular mucin pools made no prognostic difference when compared with cases of high-grade mucinous adenocarcinoma without signet ring cells. In contrast, high-grade mucinous adenocarcinoma with signet ring cells invading tissue was significant for worse survival, and thus, we propose reporting signet ring cell tissue invasion particularly when extensive

    Perioperative Systemic Chemotherapy for Appendiceal Mucinous Carcinoma Peritonei Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

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    The role of systemic chemotherapy (SC) in conjunction with cytoreductive surgery (CS) with hyperthermic intraperitoneal chemotherapy (HIPEC) in appendiceal mucinous carcinoma peritonei (MCP) is unknown

    STRIDES - STudying Risk to Improve DisparitiES in Cervical Cancer in Mississippi Ć¢ā‚¬ā€œ Design and Baseline Results of a Statewide Cohort Study

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    Cervical cancer rates in Mississippi are disproportionately high, particularly among Black individuals; yet, research in this population is lacking. We designed a statewide, racially diverse cohort of individuals undergoing cervical screening in Mississippi. Here, we report the baseline findings from this study. We included individuals aged 21 years and older undergoing cervical screening with cytology or cytology-human papillomavirus (HPV) co-testing at the Mississippi State Health Department (MSDH) and the University of Mississippi Medical Center (UMMC) (December 2017-May 2020). We collected discarded cytology specimens for future biomarker testing. Demographics and clinical results were abstracted from electronic medical records and evaluated using descriptive statistics and chi-square tests. A total of 24,796 individuals were included, with a median age of 34.8 years. The distribution of race in our cohort was 60.2% Black, 26.4% White, 7.5% other, and 5.9% missing. Approximately 15% had abnormal cytology and, among those who underwent co-testing at MSDH (n=6,377), HPV positivity was 17.4% and did not vary significantly by race. Among HPV positives, Black individuals were significantly less likely to be HPV16/18 positive and more likely to be positive for other high-risk 12 HPV types compared to White individuals (20.5% vs. 27.9%, and 79.5% and 72.1%, respectively, p=0.011). Our statewide cohort represents one of the largest racially diverse studies of cervical screening in the U.S. We show a high burden of abnormal cytology and HPV positivity, with significant racial differences in HPV genotype prevalence. Future studies will evaluate cervical precancer risk, HPV genotyping, and novel biomarkers in this population

    Reproducibility of Histopathological Diagnosis in Poorly Differentiated NSCLC: An International Multiobserver Study

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    INTRODUCTION: The 2004 World Health Organization classification of lung cancer contained three major forms of non-small-cell lung cancer: squamous cell carcinoma (SqCC), adenocarcinoma (AdC), and large cell carcinoma. The goal of this study was first, to assess the reproducibility of a set of histopathological features for SqCC in relation to other poorly differentiated non-small-cell lung cancers and second, to assess the value of immunohistochemistry in improving the diagnosis. METHODS: Resection specimens (n = 37) with SqCC, large cell carcinoma, basaloid carcinoma, sarcomatoid carcinoma, lymphoepithelial-like carcinoma, and solid AdC, were contributed by the participating pathologists. Hematoxylin and eosin (H&E) stained slides were digitized. The diagnoses were evaluated in two ways. First, the histological criteria were evaluated and the (differential) diagnosis on H&E alone was scored. Second, the added value of additional stains to make an integrated diagnosis was examined. RESULTS: The histologic criteria defining SqCC were consistently used, but in poorly differentiated cases they were infrequently present, rendering the diagnosis more difficult. Kappa scores on H&E alone were for SqCC 0.46, large cell carcinoma 0.25, basaloid carcinoma 0.27, sarcomatoid carcinoma 0.52, lymphoepithelial-like carcinoma 0.56, and solid AdC 0.21. The Īŗ score improved with the use of additional stains for SqCC (combined with basaloid carcinoma) to 0.57, for solid AdC to 0.63. CONCLUSION: The histologic criteria that may be used in the differential diagnosis of poorly differentiated lung cancer were more precisely refined. Furthermore, additional stains improved the reproducibility of histological diagnosis of SqCC and AdC, uncovering information that was not present in routine H&E stained slides

    Tubercular scrotal disease

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    Masses in the scrotum may be the result of inflammation, fluid collection and neoplasms, and involve the testis, the epididymis and/or the surrounding tunica. Epididymitis is among the most common etiologies of mass lesions and is usually infectious. The differential diagnosis of epididymitis and epididymoorchitis thus includes benign and malignant tumors, spermatic cord torsion and fluid-containing cystlike structures. In addition to a good clinical history and physical examination, the evaluation of these lesions may include Gram staining, cultures of urine and/or urethral discharges and a scrotal radiologic examination, which may include ultrasound (US), Doppler US, color duplex Doppler US and magnetic resonance imaging. Finally, if the diagnosis remains uncertain, surgical exploration is generally indicated. In the United States and much of the rest of the world, the infectious agents causing epididymitis (with or without orchitis) differ, in part, on the age of the patient.1-4 In young children, enteric coliform bacteria predominate and are associated with anatomic defects causing obstruction. In young adults, generally <40 years of age, sexually transmitted agents (Chlamydia trachomatis number 1 and Neisseria gonorrhoeae number 2 in frequency) are the most common and are associated with urethritis. Older men are typically also infected by coliform bacteria due to mechanical obstruction. Rare etiologic agents include fungi, viruses and Mycobacterium tuberculosi

    Use of fine needle aspiration biopsy in radiofrequency ablation

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    To demonstrate the utility of fine needle aspiration biopsy (FNAB) in radiofrequency ablation (RFA) of suspected metastatic tumors at various sites. STUDY DESIGN: Eighteen patients referred for RFA underwent 21 aspirations prior to the procedure. A radiologist performed the FNAB and RFA with radiographic guidance. On-site preliminary evaluation of Diff-Quik-stained smears were followed with Papanicolaou staining. A final diagnosis was rendered and compared to the preliminary diagnosis. RESULTS: Liver was aspirated in 17 cases, lung in 3 cases and pubic bone in 1. Fifteen aspirates were deemed on site as positive or suspicious for malignancy. A preliminary, on-site diagnosis of benign was given in one case and adequate with deferment for review of all slides in four others. One FNAB was unsatisfactory. All but one (patient with benign diagnosis) then immediately proceeded to RFA of the lesion. After review of additional slides, the final diagnosis confirmed metastatic adenocarcinoma in 16, hepatocellular carcinoma in 2 and metastatic squamous cell carcinoma in 1. One FNAB yielded benign hepatocytes, and one was unsatisfactory. CONCLUSION: FNAB is an accurate, safe and rapid method of confirming disease in patients just prior to undergoing RFA
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