A clinico-epidemiological study of different dermoscopic patterns in hyperpigmented facial lesions in a tertiary care centre.

Introduction: Facial pigmentation is a common presentation of patients attending dermatology out patient department (OPD) and is of great concern to patients. Facial pigmentation may be multifactorial and is only rarely diagnosed accurately by a detailed history and clinical examination. Pigmentary disorders cause psychological distress and negatively impact the quality of life of an individual. Aims and Objectives: (1) To study different dermoscopic patterns in facial melanosis. (2) To estimate the frequency of different dermoscopic patterns. Materials and Methods: Patients with facial hyperpigmentation attending the dermatology OPD were recruited after taking their written consent. A detailed history was taken to collect demographic data. Clinical examination and dermoscopy were done in all patients. Biopsy was done as and when required. Descriptive statistics has been used to describe the quantitative data. Qualitative data were presented as frequency and percentage for clinical and dermoscopic patterns. Results: The study included 100 patients with 15 different facial melanoses. The most common age group affected was 21-40 years in 53 (53%) cases. The female-to-male ratio was 1.63:1. Melasma was reported as the most common cause of facial melanosis constituting 49 (49%) of the total cases. Out of the total melasma cases, epidermal melasma constituted 22 (45%) cases, dermal melasma constituted four (4%) cases and mixed melasma constituted 23 (47%) cases. Other cases included were lichen planus pigmentosus (14; 14%), facial acanthosis nigricans (14; 14%), periorbital hyperpigmentation (7; 7%), post-inflammatory hyperpigmentation (4; 4%), exogenous ochronosis (2; 2%), lentigines (2; 2%), frictional melanosis (2;2%), and one case each of Becker's nevus, nevus of Ota, olanzapine-induced hyperpigmentation, Riehl's melanosis, macular amyloidosis, and tanning. Conclusions: Melasma was reported as the most common cause of facial melanosis. The most common dermoscopic feature was accentuated pseudopigment network. The study is beneficial in understanding the different clinical and dermoscopic patterns of facial melanosis, thus helping the physician to effectively manage the conditions and reduce the need of biopsy. Limitations: (1) A small sample size. (2) Histopathological correlation was not done in all cases.

A systematic method for diagnosis of hepatitis disease using machine learning.

Hepatitis is among the deadliest diseases on the planet. Machine learning approaches can contribute toward diagnosing hepatitis disease based on a few characteristics. On the UCI dataset, authors assessed distinct classifiers' performance in order to develop a systematic strategy for hepatitis disease diagnosis. The classifiers used are support vector machine, logistic regression (LR), K-nearest neighbor, and random forest. The classifiers were employed without class balancing and in conjunction with class balancing using SMOTE strategy. Both studies, classification without class balancing and with class balancing, were compared in terms of different performance parameters. After adopting class balancing, the efficiency of classifiers improved significantly. LR with SMOTE provided the highest level of accuracy (93.18%).

Host biology and genomic properties of Plumeria mosaic virus, a tobamovirus discovered in a temple tree in India co-infecting with frangipani mosaic virus.

Temple tree (Plumeria rubra f. acutifolia), an important fragrant-flower tree extensively used in the urban landscaping is known to be infected with a tobamovirus, frangipani mosaic virus (FrMV). In this study, we describe another tobamovirus, Plumeria mosaic virus (PluMV) infecting temple tree in India. PluMV was isolated from an old temple tree co-infected with FrMV. The presence of another tobamovirus was initially realized based on the distinct symptoms on Gomphrena globosa (globe amaranth), a non-host of FrMV. PluMV was highly transmissible through simple rub-inoculation. In host-range study, brinjal (Solanum melongena), chilli (Capsicum annuum), datura (Datura stramonium), globe amaranth and tobacco (Nicotiana benthamiana, N. glutinosa, N. tabacum cv. Xanthi) could differentiate PluMV from FrMV. The complete genome sequence of PluMV was determined (6,688 nucleotides [nt], GenBank KJ395757), which showed the genome structure typical of tobamovirus encoding four proteins: small replicase (3,549 nt/130 kDa), large replicase (5,061 nt/188 kDa), movement protein (770 nt/29 kDa) and coat protein (527 nt/19 kDa). The 5' and 3' UTR of PluMV contained 91 and 284 nt, respectively. The PluMV genome was 45 nts longer than that of FrMV and shared only 71.4-71.6% sequence identity with FrMV and < 50% sequence identity with the rest of the other members of the genus Tobamovirus. PluMV shared a close but a divergent evolutionary relationship with FrMV. Based on the species demarcation guidelines of ICTV (<90% genome sequence identity), PluMV was considered as a new tobamovirus species. As PluMV was serologically related with FrMV, differential diagnostic assays such as simplex and duplex RT-PCR were developed, which revealed that PluMV naturally existed in both the species of temple tree, P. rubra f. acutifolia and P. rubra f. obtusa in India either alone or in mixed infection with FrMV.

A CGMMV genome-replicon vector with partial sequences of coat protein gene efficiently expresses GFP in Nicotiana benthamiana.

A highly infectious clone of Cucumber green mottle mosaic virus (CGMMV), a cucurbit-infecting tobamovirus was utilized for designing of gene expression vectors. Two versions of vector were examined for their efficacy in expressing the green fluorescent protein (GFP) in Nicotiana benthamiana. When the GFP gene was inserted at the stop codon of coat protein (CP) gene of the CGMMV genome without any read-through codon, systemic expression of GFP, as well as virion formation and systemic symptoms expression were obtained in N. benthamiana. The qRT-PCR analysis showed 23 fold increase of GFP over actin at 10days post inoculation (dpi), which increased to 45 fold at 14dpi and thereafter the GFP expression was significantly declined. Further, we show that when the most of the CP sequence is deleted retaining only the first 105 nucleotides, the shortened vector containing GFP in frame of original CP open reading frame (ORF) resulted in 234 fold increase of GFP expression over actin at 5dpi in N. benthamiana without the formation of virions and disease symptoms. Our study demonstrated that a simple manipulation of CP gene in the CGMMV genome while preserving the translational frame of CP resulted in developing a virus-free, rapid and efficient foreign protein expression system in the plant. The CGMMV based vectors developed in this study may be potentially useful for the production of edible vaccines in cucurbits.

Characterisation and diagnosis of frangipani mosaic virus from India.

Frangipani mosaic virus (FrMV) is known to infect frangipani tree (Plumeria rubra f. acutifolia) in India but the virus has not been characterized at genomic level and diagnosis is not available. In the present study, an isolate of FrMV (FrMV-Ind-1) showing greenish mosaic and vein-banding symptoms in P. rubra f. acutifolia in New Delhi was characterized based on host reactions, serology and genome sequence. The virus isolate induced local symptoms on several new experimental host species: Capsicum annuum (chilli), Nicotiana benthamiana, Solanum lycopersicum and S. melongena. N. benthamiana could be used as an efficient propagation host as it developed systemic mottle mosaic symptoms all round the year. The genome of FrMV-Ind-1 was 6643 (JN555602) nucleotides long with genome organization similar to tobamoviruses. The Indian isolate of FrMV shared a very close genome sequence identity (98.3 %) with the lone isolate of FrMV-P from Australia. FrMV-Ind-1 together with FrMV-P formed a new phylogenetic group i.e. Apocynaceae-infecting tobamovirus. The polyclonal antiserum generated through the purified virus preparation was successfully utilized to detect the virus in field samples of frangipani by ELISA. Of the eight different tobamoviruses tested, FrMV-Ind-1 shared distant serological relationships with only cucumber green mottle mosaic virus, tobacco mosaic virus, bell pepper mottle virus and kyuri green mottle mosaic virus. RT-PCR based on coat protein gene primer successfully detected the virus in frangipani plants. This study is the first comprehensive description of FrMV occurring in India.