ABSTRACT
Organic material-based bioelectronic nonvolatile memory devices have recently received a lot of attention due to their environmental compatibility, simple fabrication recipe, preferred scalability, low cost, low power consumption, and numerous additional advantages. Resistive random-access memory (RRAM) devices work on the principle of resistive switching, which has the potential for applications in memory storage and neuromorphic computing. Here, natural organically grown orange peel was used to extract biocompatible pectin to design a resistive switching-based memory device of the structure Ag/Pectin/Indium tin oxide (ITO), and the behavior was studied between a temperature range of 10K and 300K. The microscopic characterization revealed the texture of the surface and thickness of the layers. The memristive current-voltage characteristics performed over 1000 consecutive cycles of repeated switching revealed sustainable bipolar resistive switching behavior with a high ON/OFF ratio. The underlying principle of Resistive Switching behavior is based on the formation of conductive filaments between the electrodes, which is explained in this work. Further, we have also designed a 2 × 2 crossbar array of RRAM devices to demonstrate various logic circuit operations useful for neuromorphic computing. The robust switching characteristics suggest possible uses of such devices for the design of ecofriendly bioelectronic memory applications and in-memory computing.
ABSTRACT
(1) Objective: To review the criteria proposed by Cerero-Lapiedra et al. and to retrospectively identify the under-diagnosed disease in patients diagnosed with proliferative verrucous leukoplakia. (2) Materials and methods: In this study, we included patients who were diagnosed with leukoplakia (histological label consistent with the clinical diagnosis, n = 95), and cases with a final diagnosis within the spectrum of proliferative verrucous leukoplakia (n = 110) as defined by Batsakis et al. We applied the criteria proposed by Cerero-Lepiedra et al. to screen for the possible cases of proliferative verrucous leukoplakia. (3) Results: Although many of our patients satisfied specific isolated criteria, only 11 cases satisfied specific combinations of the guidelines to satisfy a diagnosis of proliferative verrucous leukoplakia. However, due to the lack of follow-up data, the disease is not confirmed in these 11 cases. (4) Conclusion: A limited number of cases of proliferative verrucous leukoplakia were diagnosed using the criteria given by Cerero-Lapiedra et al. The true natural history of the disease could not be studied due to the lack of follow-up data. (5) Clinical relevance: Proliferative verrucous leukoplakia presenting as hyperkeratosis or mild epithelial dysplasia are often not followed up, and they subsequently transform into carcinoma. Thus, clinicians must be vigilant whenever they encounter leukoplakia, especially with multifocal presentations. In such cases, the follow-up data are the key to understanding the true nature of the disease entity.
ABSTRACT
BACKGROUND: Researchers have struggled to understand the natural history of lesions presenting with both lichenoid features and epithelial dysplasia. Thus the present study was designed to differentiate between OLP, OLP with dysplasia, epithelial dysplasia and epithelial dysplasia with lichenoid features based on the expressions of ki-67, p53, COX-2, and α-SMA. MATERIALS AND METHODS: Formalin-fixed paraffin-embedded archival specimens of OLP, OLP with dysplasia, epithelial dysplasia and epithelial dysplasia with lichenoid features were subjected to immunohistochemical staining with ki-67, p53, COX-2, and α-SMA. RESULTS: Ki-67 exhibited strong positivity in 100% (6/6) of epithelial dysplasia cases, 71.4% (5/7) of lichenoid dysplasia cases, 57.1% (4/7) of OLP cases and 60% (3/5) of OLP with dysplasia cases. Strong p53 staining was evident in more cases of lichenoid dysplasia [42.8% (3/7)], while moderate staining was more frequent in OLP cases [42.8% (3/7)] and OLP with dysplasia cases [42.8% (3/7)] and mild intensity was more frequent in epithelial dysplasia cases [50% (3/6)] followed by lichenoid dysplasia cases [42.8% (3/7)], OLP cases [28.5 (2/7)] and OLP with dysplasia cases [40% (2/5)]. COX-2 strong positivity was more frequent in cases of epithelial dysplasia cases [57.1% (4/7)] and OLP [50% (3/6)]. Strong α- SMA staining was noted more frequently in lichenoid dysplasia cases [71.4 (5/7)], followed by OLP cases [42.8% (3/7)] and OLP with dysplasia cases [60% (3/5)]. CONCLUSIONS: Ki-67, p53, α-SMA and COX-2 expression do not differentiate between OLP, LP with dysplasia and epithelial dysplasia with lichenoid features.
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INTRODUCTION: Oral carcinoma is a global health problem. India accounts for one-third of world burden with high prevalence rate of 2.5 million and mortality rate of 5.5 lacs per year. Oral carcinogenesis is a multistage process that frequently involves invasion and metastasis that needs early detection and treatment to improve the overall quality of life. The ability of Oral Squamous Cell Carcinoma (OSCC) to metastasize to lymph nodes does not always show a relationship with clinical staging. A spectrum of molecular mechanisms is involved in carcinogenesis, where defect in the regulation of apoptosis is assumed to contribute to the pathogenesis and progression of cancer. Apoptosis regulatory genes include the antiapoptotic protein such as B-cell lymphoma-2 (Bcl-2) gene that might be used as a molecular marker to evaluate the biological behaviour of oral cancer. AIM: To evaluate and correlate the Bcl-2 expression in OSCC patients with lymphnode metastasis and without metastasis. MATERIALS AND METHODS: The study comprised of 30 samples, 15 cases of metastatic and 15 non-metastatic primary OSCC. All the cases were stained for routine Hematoxylin and Eosin (H&E), and Bcl-2 antibody by immunohistochemistry. The H&E stained sections were evaluated for Lymphocytic Infiltrate (LI) and Pattern Of Invasion (POI). Bcl-2 stained sections were evaluated for staining intensity and distribution. The differences between the groups were statistically analysed using chi-square test. RESULTS: The histopathological parameters, LI and POI did not show any statistical difference between the study groups. Expression of Bcl-2 in OSCC was 33.3% among the study groups, where metastatic group showed a positive expression of 13.3% and 20% in non-metastatic OSCC that did not show statistically significance among the study groups. CONCLUSION: There was no significant difference in the expression of Bcl-2 between the study groups. Apoptosis is regulated by interaction among the Bcl-2 gene family. Hence, evaluation of Bcl-2 along with other apoptotic regulating proteins could define the role in pathogenesis and prognosis of metastatic and non-metastatic OSCC.
ABSTRACT
Basaloid Squamous Cell Carcinoma (BSCC) is a rare entity with its histopathological distinction from conventional squamous cell carcinoma. It is frequently considered a high-grade carcinoma with poor prognosis because of higher rate of distant metastases. Here by, we are reporting a case of 39-year-old male with an ulcer on the left lateral border of the tongue since a month. Histopathological examination of incisional biopsy revealed basaloid tumour cell islands accompanied by component of well differentiated squamous cell carcinoma. To reconfirm this incidental finding immunohistochemistry was carried out for Proliferative Cell Nuclear Antigen (PCNA) and pancytokeratin (AE1/AE3) which was positive to conclude diagnosis of BSCC. Further p16 staining was done to rule out Human Papilloma Virus (HPV) infection.
ABSTRACT
AIM: The aim of the present study was to evaluate, compare, and correlate the types of collagen fibers seen in different grades of oral cancer. METHODS: Thirty cases of histologically-diagnosed, well-, moderately-, and poorly-differentiated oral squamous cell carcinoma (OSCC) were retrieved from the archives of the Institute. Collagen was evaluated using picrosirius red stain and immunohistochemical analysis of the antibody to type III collagen. A correlation between these findings and the grade of OSCC was evaluated. RESULTS: Collagen fibers showed a change in birefringence ranging from reddish-orange to greenish-yellow in well- to poorly-differentiated oral squamous cell carcinoma. The findings were statistically significant for polarizing colors observed in grades of OSCC (P<.001). Immunohistochemical staining intensity of type III collagen changed from weak to strong as grade increased for OSCC, and was also statistically significant (P<.001). CONCLUSION: In the present study, tumor progression reflected a change in collagen present, from type I to type III. Determination of the type of collagen in different grades of OSCC can facilitate therapeutic targeting of molecules responsible for invasion and progression of oral cancer.
