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Virendra N Sehgal

Publications and source records attributed to Virendra N Sehgal.

10 recordsLinked to original sources
PubMed2003

Retinoids: fascinating up-and-coming scenario.

Retinoids have been in sharp focus ever since their introduction 30 years ago. They include any drug (s) that bind to retinoid receptors and elicit a biological response. Enormous information on the subject seems to embroil the recent literature. Practically it is impossible to clearly comprehend the undercurrents. The meticulously dispensing text envisages surmounting the perspective reader's predicaments. Accordingly, retinoids and their related facets namely retinoid receptors, classification, mode of action, and the pharmacological diversity have been precisely defined. Commonly used systemic retinoids too have been given a substantial fresh look along with their monitoring. Overall, adverse effects and relative and absolute contraindications have been scrupulously incorporated. Human immuno deficiency virus (HIV) and isoretinoid for acne, in particular, have been highlighted. Micronized isotretinoin formulations have also been taken care so also commonly used topical retinoids. Tretinoin and their newer formulation have also been accounted for along with tretinoin polymer cream. Adapalene, a new chemical entity possessing a unique physico-chemical activity similar to that of tretinoin has also been dealt with. Newer retinoids are likely to be a subject of intrigue. A focus on future potentials of retinoids is its special ingredient. The inclusion of details of rexinoid the most recent introduction in their purview is likely to invoke interest to further consolidate its reckoning in future. All in all the text of the paper should provide an insight into the current rumbling around retinoids.

Acne Vulgaris↗
PubMed2002

Epidermodysplasia verruciformis: 14 members of a pedigree with an intriguing squamous cell carcinoma transformation.

A 38-year-old farmer was apparently well until 5 years of age. At this age, the patient's mother found mildly itchy, raised eruptions over the scalp during combing of the scalp hair. Since then, the eruptions have progressed insidiously to involve the face and other parts of the body, with a preponderance over the face, upper back, and chest, including the palms. The soles, oral cavity, and genital tract were unaffected. The lesions were persistent in nature and showed no remission or exacerbation. Mild to moderate pruritus/discomfort was experienced following sunlight exposure. A prominent, raised eruption appeared on the right side of the forehead 9 years ago, 25 years after the initial eruptions, which in due course ulcerated. It was progressive in nature and acquired a large size. Two years later, it was diagnosed as squamous cell carcinoma, for which liquid nitrogen cryosurgery was performed. There was a recurrence of the lesion at the site of surgery, which was excised 4 months later. Subsequently, there was a sudden flare up at the same site. It was badly infected with maggot infestation. The relentless course of the disease was evident by the appearance of two similar lesions, one on the right half of the nose and the other on the left preauricular region. A short while ago, fatigue and loss of weight were also recorded. Bladder and bowel functions were normal and there was no loss of appetite, hoarseness of voice, or breathlessness. Four of the patient's six children (three sons and one daughter) were reported to have similar lesions all over the body. In addition, nine other relatives were also affected. Accordingly, a total of 14 (12 males and two females) family members were found to be affected from amongst 41 individuals (26 males and 15 females) spread across several generations (Fig. 1). There was a second-degree consanguinity of marriage, with the patient's grandmother and wife's father being brother and sister. Skin surface examination was marked by multiple, discrete, flat-topped, scaly, brownish-black papules of diverse morphology, from hypopigmented macules to verrucous lesions, with a few coalescing to form plaques. The scales were brown, dry, and adherent (Fig. 2a). The lesions were conspicuous by their presence over the face, neck, and front and back of the chest. The extremities were also affected. Nevertheless, the soles and genitalia were spared. The oral mucosae, hair, and nails were normal. Koebner's phenomenon was explicit, whereas Auspitz's sign was not demonstrable. In addition, a perceptible nodulo-ulcerative lesion (size, 3 in x 2 in) with indurated, raised, averted margins was encountered on the right side of the forehead. The ulcer was tender and had a fetid discharge. Necrotic slough was prominent over its base. Similar lesions were located on the left preauricular region and right half of the nose. Hematoxylin and eosin-stained sections prepared from biopsies taken from representative lesions of epidermodysplasia verruciformis and squamous cell carcinoma revealed their diagnostic features. Epidermodysplasia verruciformis showed features of hyperkeratosis and acanthosis with hardly any papillomatosis. Marginal elongation of the rete ridges was present. Extensive vacuolization was a remarkable feature, and was largely confined to the upper stratum Malpighian and the granular cell layer. Some of the vacuolated cells were fairly large; their nuclei were located in the center and had variable pyknosis. The granular cell layer was uniformly thickened, whereas the stratum corneum had a loosely felted (basket-weave) appearance. The dermis was apparently normal (Fig. 2b,c). The other microsection(s) from squamous cell carcinoma were conspicuous by the presence of hyperkeratosis, acanthosis, and irregular masses of epidermal cells, proliferating downwards and invading the dermis. Varying proportions of differentiated squamous cells formed their bulk. These cells were atypical, characterized by variations in size and shape, hyperplasia and hyperchromasia of the nuclei, absence of prickles, chas, characterization of individual cells, and the presence of both mitotic and atypical mitotic figures (Fig. 3b).

Adult↗
PubMed2002

En coup de sabre.

A man born in 1961 was apparently well until his marriage in May 1986. In August of that year, his attention was drawn to the presence of a reddish patch over the right forehead. It was initially asymptomatic. It continued to progress to form an apparent linear furrow extending from the receding hairline to the vertex and temporal part of the scalp. At this juncture, the patient experienced moderate pain when laughing. Five years later the patient experienced a constant boring pain affecting the right eyeball. Consultation with an ophthalmologist led to sacrificial enucleation of the right eye despite the lack of a precise diagnosis. Nevertheless, the initial condition continued to progress causing disfigurement of the right side of the face. Examination of the face was marked by perceptible asymmetry. A linear atrophic plaque in the form of a furrow was identified on the right side of the forehead extending from the eyebrow to the vertex and temporal part of the scalp. The skin over the furrow was taut and bound down (Fig. 1). A hematoxylin and eosin-stained section prepared from the lesion revealed marked thickening of the dermis. The collagen bundles were hypertrophied and closely packed together. The staining was homogeneously eosinophilic. It was largely devoid of inflammatory infiltrate. The changes in the blood vessels were conspicuous by narrowing of the lumina, thickening of the walls, and a sparse perivascular lymphocytic infiltrate. Pilosebaceous units were completely absent, whereas a few atrophic pulled-up sweat glands were located in the mid-dermis. Similar changes were observed in the subcutaneous tissue. The epidermis was largely atrophied, with flattening of the rete ridges.

Adult↗