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N-Alkylated indanylidene-pyrroline-based molecular switches mimic different aspects of the light-induced retinal chromophore isomerization in rhodopsin: the vertebrate dim-light visual pigment. In particular, they display a similar ultrashort excited-state lifetime, subpicosecond photoproduct appearance time, and photoproduct vibrational coherence. To better understand the early light-induced dynamics of such systems, we measured and modeled the resonance Raman spectra of the Z-isomer of the N-methyl-4-(5'-methoxy-2',2'-dimethyl-indan-1'-ylidene)-5-methyl-2,3-dihydro-2H-pyrrolium (NAIP) switch in methanol solution. It is shown that the data, complemented with a <70 fs excited-state trajectory computation, demonstrate initial excited-state structural dynamics dominated by double-bond expansion and single-bond contraction stretches. This mode subsequently couples with the five-membered ring inversion and double-bond torsion. These results are discussed in the context of the mechanism of the excited-state photoisomerization of NAIP switches in solution and the 11-cis retinal in rhodopsin.

Symmetrical drug-related intertriginous and flexural exanthema (SDRIFE) is an adverse drug reaction which has been reported to be caused by various drugs. In this report, we describe a case induced by ranitidine, a drug which has not been previously reported to cause SDRIFE.

In order to understand the effect of methyl substitution patterns on the initial excited-state structural dynamics of uracil derivatives, we measured the resonance Raman spectra of 5,6-dimethyluracil (5,6-DMU). The results show that the resonance Raman spectrum is a combination of that of 5-methyl- and 6-methyluracil. The resonance Raman excitation profiles (RREPs) and absorption spectrum are simulated with a self-consistent, time-dependent formalism to yield the excited-state slopes and broadening parameters. The initial excited-state structural dynamics occur primarily along the C5═C6 stretching mode, as expected, but with lesser excited-state slopes along each mode compared to 5-methyluracil and 6-methyluracil. This study along with previous experiments with different uracil derivatives show that the presence and positions of the methyl groups seems to determine the partitioning of initial excited-state structural dynamics.

Objective: To assess the profile and describe the clinical presentations and complications of childhood leprosy in a tertiary care hospital in North Kerala, South India during 2003-2012 and to analyse any change in the age-sex profile and the clinical pattern of leprosy in children below the age of 15 years over the 10-year study period., Design: A retrospective descriptive study of children less than 15 years of age diagnosed with leprosy and registered for treatment in a tertiary care institution from 2003 to 2012. Demographic, clinical, investigative and treatment data were collected using a pre-set proforma., Results: 138 (12.1%) of the total 1143 leprosy cases registered for treatment during the 10-year period were below 15 years of age. The 10-year study period witnessed a statistically insignificant decrease in the new childhood leprosy cases registered for treatment in our tertiary care institution. The majority of cases belonged to the 6-12 year age group (61.6%) with a male predominance. Borderline tuberculoid (BT) was the commonest clinical type (65.9%) followed by indeterminate leprosy (18.8%); 101 patients required paucibacillary (PB) and 37 needed multibacillary (MB) treatment. The number of patients requiring MB treatment showed a statistically significant increase and there was a significant decline in number of cases requiring PB treatment. During the entire study period no Type 2 lepra reaction was documented in patients below Hema 15 years and only two patients manifested Type 1 reaction. Ten (7.2%) out of the 138 patients were cases of relapse. There was a clear female predilection among relapse cases with the majority belonging to the adolescent age., Conclusions: Childhood leprosy still contributes to a significant proportion of the total case load denoting the continuing active horizontal transmission of leprosy. The rise in number of patients with more extensive disease in the background of declining disease prevalence is suggestive of the delay in diagnosis and treatment. A high relapse rate noted in the present study may be due to incorrect classification and treatment of MB as PB leprosy which in turn might have resulted in treatment failure due to inadequate treatment.

Background: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe drug reaction which can mimic a viral infection, an autoimmune disease or a neoplastic disease., Aims: To study the clinical and epidemiological aspects of DRESS and to identify the precipitating drugs., Methods: All patients admitted to the dermatology ward of our tertiary care hospital from 1 st October 2010 to 30 th September 2013 with probable or definite DRESS as per the RegiSCAR scoring system were included in this prospective study. The clinical manifestations observed in the study population were studied and the common offending drugs were identified., Results: During the 3 year study period, 26 patients fulfilled criteria for probable or definite DRESS. In more than 50% of cases, the culprit drug was phenytoin. Most common symptoms observed were fever, rash and facial edema. Liver was the most common internal organ affected. Most of the patients responded to withdrawal of the drug and administration of steroids for 3-6 weeks. One patient with dapsone-induced DRESS died., Conclusions: Intense facial erythema and edema and an elevated eosinophil count were not found to be bad prognostic factors. In most instances the flare ups during the course of the disease could be managed with a slower tapering of steroids. More prospective studies on DRESS are required to assess the prognostic factors and to formulate better diagnostic criteria.

Leprosy is a chronic infectious disease with a wide spectrum of signs and symptoms depending on the ability of the host's immune system to resist the infection. The disease is frequently associated with sensory loss in skin lesions and damage in peripheral nerve trunks leading to nerve function impairment. In lepromatous leprosy, the immune system offers no protection against the multiplying bacilli and this results in heavy infiltration of the internal organs. We report a case of florid lepromatous leprosy with bone marrow suppression due to the disease, presenting with anemia, leukocytopenia and thrombocytopenia. The hematological abnormalities were fully reversed by mutidrug therapy for leprosy. We suggest that infiltration of the bone marrow by Mycobacterium leprae can cause pancytopenia, which can be cured by treatment of the leprosy alone.

Objectives: 1. To study and compare the clinical and histological features of Type 1 and Type 2 lepra reactions. 2. To document the histological patterns of Type 1 and Type 2 lepra reactions observed in the study population., Design: Two year cross sectional study. Patients attending the outpatient department of our tertiary care hospital, during the 2 year study period with clinical evidence of Type 1 (T1R) or Type 2 (T2R) lepra reactions were included in this study after obtaining written informed consent. During this period 34 T1R patients and 14 T2R patients attended our hospital. Biopsies were taken from reacting skin lesions of all patients and histological features were studied., Results: Dermal or intragranuloma oedema was evident in 50% of T1R patients and all of them had clinically severe reactions. The T1R patients showed three different histological patterns--pgrading reactions, downgrading reactions and reactions without upgrading or downgrading. Among T2R patients 8/14 showed neutrophil infiltration histologically, 5/14 showed no histological evidence of neutrophil infiltration and only one patient had features of neutrphilic vasculitis. Dermal oedema was seen in 11/14 cases., Conclusions: Histology revealing dermal or intragranuloma oedema on a background of leprosy granuloma favours the diagnosis of lepra reaction. A careful analysis of subtle variations in the cells constituting the granuloma may aid in differentiating between upgrading T1R, downgrading T1R or T1R without upgrading or downgrading. Histology can also be useful in distinguishing T2R from T1R, in the absence of typical erythema nodosum leprosum (ENL) lesions. Neutrophils are the major inflammatory cells in the former where as lymphocytes or macrophages predominate in the latter. We recommend that histopathological analysis should form an integral part of the evaluation of all lepra reactions.

Autonomic dysreflexia occurs in patients with spinal cord injury, and is characterized by unbalanced sympathetic discharge, precipitated by noxious stimuli from a site below the spinal cord lesion. An 11-year-old boy with acute disseminated encephalomyelitis and spinal cord involvement manifested episodes of intense flushing and sweating, confined to the head and neck region, and associated with hypertension and tachycardia. His signs improved after changing a partly blocked bladder catheter. The clinical features suggested autonomic dysreflexia. Early recognition of autonomic dysreflexia is important because removal of the trigger precipitating the event may be life-saving., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Adult T-cell leukemia/lymphoma (ATLL) is an aggressive leukemia/lymphoma of mature T-lymphocytes caused by human T-cell lymphotropic virus type 1 (HTLV-1). At a tertiary healthcare center in South India, a 58-year-old female presented with multiple erythematous, crusted, and umbilicated papules over the body along with cervical lymphadenopathy. The skin biopsy was consistent with cutaneous T-cell lymphoma. Although she responded initially to chemotherapy, the disease relapsed after 3 months, and she developed disseminated infiltrated skin lesions, generalized lymphadenopathy, and leukemia. Due to the unusual clinical findings we did HTLV-1 Enzyme-linked immunosorbent assay (ELISA), which turned out to be positive in high titers. Her mother had died at an early age from a hematological malignancy and her daughter was also found to be seropositive. To the best of our knowledge, this is the first case to be reported from India of the chronic type of ATLL associated with mother-to-child transmission of HTLV-1 in two generations. This case also emphasizes that the chronic type of ATLL can occur in nonendemic areas like India and should be suspected in nonresponding cases of mycosis fungoides. It should be kept in mind that the chronic type often presents without hypercalcemia or the characteristic 'flower cells' in the peripheral smear.

Background: Chikungunya (CHIK) is an emerging viral disease with a myriad of cutaneous manifestations., Aims: The aim of our study was to document the morphology and evolution of skin lesions in cases presenting with fever, purpuric macules and vesiculobullous lesions, to confirm its causative relationship with CHIK, and to investigate further in order to delineate possible mechanisms of bulla formation in these cases., Materials and Methods: A prospective, descriptive hospital-based study was carried out at a tertiary health care centre in Kerala. A total of 10 patients were enrolled in the study and investigated., Results: All cases had morbilliform eruption prior to onset of purpuric macules. Eight cases developed vesiculobullous lesions that arose either de novo or over a part or whole of the purpuric macules. Skin lesions resolved within an average of 7.6 days leaving post-inflammatory hypopigmentation. IgM CHIK enzyme-linked immunosorbent assay (ELISA) was positive in all 10 patients. Tzanck smear from the bullae showed lymphocytes in most cases along with acantholytic cells, necrotic keratinocytes or occasional neutrophils. Skin biopsy showed intraepidermal or subepidermal bullae. Immunohistochemistry revealed predominantly CD8 positive T lymphocytes in the infiltrate. The prognosis was good with supportive management alone., Discussion: The clinical features in our cases are comparable to the 3 previous reports of vesiculobullous lesions in CHIK affected infants. Based on the current evidence, we hypothesize that at least 2 mechanisms are at play for these skin lesions; CHIK virus induced keratinocyte necrosis followed by a cytotoxic immune response, and possible modulation of rash by drugs., Conclusion: With severe epidemics of CHIK spreading from Asia and Africa to the Western hemisphere, we must consider bullous CHIK as a differential diagnosis in cases with fever and purpuric and vesiculobullous lesions., (© 2011 The International Society of Dermatology.)