Pigmentation on Gingiva: A Diagnostic Dilemma

Pigmentation on gingiva can be physiologic or pathologic. Gingival pigmentation is present from birth in certain individuals. However, sudden occurrence of pigmentation suggests some systemic association. In the present case, a patient was referred by a physician for biopsy of the tissue along with gingival depigmentation. The depigmentation procedure was performed in both arches, and the biopsy specimen was sent for histopathologic examination. This case highlights the importance of biopsy of gingival pigmentation with a history of sudden occurrence. A biopsy is warranted to distinguish pathologic pigmentation from physiologic.

Absolute quantitative profiling of the key metabolic pathways in slow and fast skeletal muscle

Slow and fast skeletal muscles are composed of, respectively, mainly oxidative and glycolytic muscle fibers, which are the basic cellular motor units of the motility apparatus. They largely differ in excitability, contraction mechanism, and metabolism. Because of their pivotal role in body motion and homeostasis, the skeletal muscles have been extensively studied using biochemical and molecular biology approaches. Here we describe a simple analytical and computational approach to estimate titers of enzymes of basic metabolic pathways and proteins of the contractile machinery in the skeletal muscles. Proteomic analysis of mouse slow and fast muscles allowed estimation of the titers of enzymes involved in the carbohydrate, lipid, and energy metabolism. Notably, we observed that differences observed between the two muscle types occur simultaneously for all proteins involved in a specific process such as glycolysis, free fatty acid catabolism, Krebs cycle, or oxidative phosphorylation. These differences are in a good agreement with the well-established biochemical picture of the muscle types. We show a correlation between maximal activity and the enzyme titer, suggesting that change in enzyme concentration is a good proxy for its catalytic potential in vivo. As a consequence, proteomic profiling of enzyme titers can be used to monitor metabolic changes in cells. Additionally, quantitative data of structural proteins allowed studying muscle type specific cell architecture and its remodeling. The presented proteomic approach can be applied to study metabolism in any other tissue or cell line.

Raman mapping of oral buccal mucosa: a spectral histopathology approach

Oral cancer is one of the most common cancers worldwide. One-fifth of the world's oral cancer subjects are from India and other South Asian countries. The present Raman mapping study was carried out to understand biochemical variations in normal and malignant oral buccal mucosa. Data were acquired using WITec alpha 300R instrument from 10 normal and 10 tumors unstained tissue sections. Raman maps of normal sections could resolve the layers of epithelium, i.e. basal, intermediate, and superficial. Inflammatory, tumor, and stromal regions are distinctly depicted on Raman maps of tumor sections. Mean and difference spectra of basal and inflammatory cells suggest abundance of DNA and carotenoids features. Strong cytochrome bands are observed in intermediate layers of normal and stromal regions of tumor. Epithelium and stromal regions of normal cells are classified by principal component analysis. Classification among cellular components of normal and tumor sections is also observed. Thus, the findings of the study further support the applicability of Raman mapping for providing molecular level insights in normal and malignant conditions.

Standard operating procedure for audio visual recording of informed consent: an initiative to facilitate regulatory compliance

The office of the Drugs Controller General (India) vide order dated 19 th November 2013 has made audio visual (AV) recording of the informed consent mandatory for the conduct of all clinical trials in India. We therefore developed a standard operating procedure (SOP) to ensure that this is performed in compliance with the regulatory requirements, internationally accepted ethical standards and that the recording is stored as well as archived in an appropriate manner. The SOP was developed keeping in mind all relevant orders, regulations, laws and guidelines and have been made available online. Since, we are faced with unique legal and regulatory requirements that are unprecedented globally, this SOP will allow the AV recording of the informed consent to be performed, archived and retrieved to demonstrate ethical, legal and regulatory compliance. We also compared this to the draft guidelines for AV recording dated 9 th January 2014 developed by Central Drugs Standard Control Organization. Our future efforts will include regular testing, feedback and update of the SOP.

Apoptotic cascade inspired lipid nanovesicles show synergism with encapsulated paclitaxel in chemoresistant colon carcinoma

Inspired from the apoptotic cascade, we developed phosphatidylserine (PS)-based proapoptotic lipid nanovesicles, capable of bypassing drug resistance and exhibiting synergistic anticancer activity with encapsulated paclitaxel in chemoresistant human colon adenocarcinoma (HCT-15).

MATERIALS & METHODS

Nanovesicles were developed and evaluated both in vitro and in vivo for their proapoptotic activity, synergism with encapsulated paclitaxel and ability to bypass drug resistance.

RESULTS

110 ± 7 nm sized nanovesicles were found to be proapoptotic and synergistic with paclitaxel, and bypassed drug resistance. The formulation, with synergistic inputs from PS and paclitaxel, downregulated Ki-67 and inhibited angiogenesis leading to apoptosis by activating caspase-3 and downregulating Bcl-2, resulting in DNA fragmentation. The nanovesicles, while increasing the systemic circulation time of paclitaxel by 6.9-fold reduced systemic toxic effects of paclitaxel and were found to be nonimmunogenic.

CONCLUSION

These results suggest the therapeutic potential of PS-based proapoptotic nanovesicles encapsulating paclitaxel in chemoresistant human colon carcinoma.

In vivo Raman spectroscopy of oral buccal mucosa: a study on malignancy associated changes (MAC)/cancer field effects (CFE)

Occurrence of metachronous and synchronous secondary tumors in oral cavities has been associated with poor prognosis and decreased 5-year disease-free survival rates. The origin of secondary tumors in the oral cavity has been primarily attributed to cancer field effects (CFE) or malignancy-associated changes (MAC) in uninvolved areas. Classification of normal, cancerous and pre-cancerous oral lesions by in vivo Raman spectroscopy (RS) has already been demonstrated. In the present study, MAC/CFE in oral buccal mucosa were explored. In vivo Raman spectra from 84 subjects (722 spectra) under five categories - cancer and contralateral normal (opposite side of tumor), healthy controls (no tobacco habit, no cancer), habitués healthy controls (tobacco habit, no cancer) and non-habitués contralateral normal (no tobacco habit with cancer) were acquired. Mean and difference spectra suggest that loss of lipids and additional features representing proteins and DNA are characteristics of all pathological conditions, with respect to healthy controls. Spectral data were analyzed by PC-LDA followed by leave-one-out cross-validation. Results suggest that Raman characteristics of mucosa of healthy controls are exclusive, while those of habitués healthy controls are similar to those of contralateral normal mucosa. It was observed that the cluster of non-habitués contralateral normal mucosa is different from habitués healthy controls, suggesting that malignancy associated changes can be identified and also indicating that transformation of uninvolved oral mucosa due to tobacco habit or malignancy is different. The findings of the study demonstrate the potential of RS in identifying early transformation changes in oral mucosa and the efficacy of this approach in oral cancer applications.

Cysticercosis of the upper lip

Cysticercosis is a parasitic infestation caused by the larval stage of Taenia solium. It is common in regions where humans and animals live in close contact, with poor sanitation, and due to consumption of infected meat. The tissues affected are the subcutaneous layers, brain, muscle, heart, liver, lungs, and peritoneum. Oral manifestations are very rare. The most common intra-oral site is the tongue. Here, we present a case in a who sought treatment for an asymptomatic nodule in the upper lip. A gross specimen revealed a cystic cavity containing clear watery fluid and white membranous flecks. The histopathology showed features of cysticercosis.

Ancient schwannoma of the parapharynx causing dysphagia: a rare entity

A schwannoma is a benign, encapsulated tumour that is derived from neural sheath (Schwann) cells. Approximately 25-40% of schwannomas occur in the head and neck. The most common site is the parapharyngeal space of the neck; oropharyngeal occurrence is extremely rare. Among the various histological types of schwannomas reported to date, the ancient (degenerative) variant is the most rare. To our knowledge, this is the first report of an ancient schwannoma in the parapharynx with an extensive oropharyngeal component causing dysphagia. Dysphagia was the prominent symptom because of the location and volume of the lesion. The tumour was excised via a transcervical approach.

Raman Spectroscopy of Oral Buccal Mucosa: A Study on Age-Related Physiological Changes and Tobacco-Related Pathological Changes

Biophysical techniques play an important role in detecting physiological alterations during pathogenesis. Raman spectroscopy has shown immense potential in identifying several diseased conditions, including oral cancers. Classification of normal, inflammatory, premalignant and malignant conditions has been demonstrated using ex vivo Raman spectroscopy. Feasibility of recording in vivo spectra in clinically implementable time has also been shown. Translation of this technology to clinics requires extensive validation of methodologies, building of robust models and testing the same under stringent conditions as well as on diverse populations. In this context, the ability of Raman spectroscopy in identifying subtle changes in oral mucosa with increasing age, and the influence of these aging related changes on classification with tobacco-related pathological changes was evaluated. A total of 451 spectra from 62 subjects were recorded from buccal mucosa of healthy subjects of 4 different age groups (aged 20–60 years). Also, 478 spectra from 85 subjects belonging to 4 different categories, tobacco exposed mucosa, contralateral normal (opposite side of tumor), premalignant patches and tumors on buccal mucosa were recorded using fiber optic probe-coupled commercial Raman spectrometer. Differences in spectra were explored by unsupervised Principal Component Analysis (PCA) and supervised Linear Discriminant Analysis (LDA), followed by Leave one out cross validation. Results indicate feasibility of classifying early and late age groups. Also, clear classification is observed between healthy and pathological groups, thus inherent heterogeneity in healthy groups seems to have no bearing on classification of normal with abnormal conditions. Findings of the study indicate high sensitivity of Raman spectroscopy in detecting subtle mucosal changes, further supporting efficacy of Raman spectroscopic approaches in oral cancer applications. Prospectively, more vigorous validation studies of Raman methodology would enable routine clinical applications.