Investigation of miscibiliy and physicochemical properties of synthetic polypeptide with collagen blends and their wound healing characteristics.

A suitable condition is needed to foster a rapid recovery of wounds, which is a dynamic and intricate process. The development and characterization of mats of plastic-like peptide polymer (PLP) with collagen for wound healing applications are reported in this work. Viscosity parameters such as the Huggins coefficient [KH], the intrinsic viscosity [η], α by Sun, ∆[η]m by Garcia ∆B and µ suggested by Chee, ∆K, and ß advocated by Jiang and Han, recommend the miscibility of the polypeptide in solution phase. Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray diffraction (XRD) methods in a solid phase. Thermal characteristics using a differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA) showed higher stability for the blends than the pure polymers. The collagen and PLP blends showed exceptional in vitro cytocompatibility, and the in vivo wound-healing studies on the Sprague-Dawley rats demonstrated faster wound healing within two weeks compared to the cotton gauze-treated injuries. Therefore, these membranes can be a possible alternative for treating skin injuries.

Molecular modelling and simulation techniques to investigate the effects of fungal metabolites on the SARS-CoV-2 RdRp protein inhibition.

Various protein/receptor targets have been discovered through in-silico research. They are expanding rapidly due to their extensive advantage of delivering new drug candidates more quickly, efficiently, and at a lower cost. The automation of organic synthesis and biochemical screening will lead to a revolution in the entire research arena in drug discovery. In this research article, a few fungal metabolites were examined through an in-silico approach which involves major steps such as (a) Molecular Docking Analysis, (b) Drug likeness and ADMET studies, and (c) Molecular Dynamics Simulation. Fungal metabolites were taken from Antibiotic Database which showed antiviral effects on severe viral diseases such as HIV. Docking, Lipinski's, and ADMET analyses investigated the binding affinity and toxicity of five metabolites: Chromophilone I, iso; F13459; Stachyflin, acetyl; A-108836; Integracide A (A-108835). Chromophilone I, iso was subjected to additional analysis, including a 50 ns MD simulation of the protein to assess the occurring alterations. This molecule's docking data shows that it had the highest binding affinity. ADMET research revealed that the ligand might be employed as an oral medication. MD simulation revealed that the ligand-protein interaction was stable. Finally, this ligand can be exploited to develop SARS-CoV-2 therapeutic options. Fungal metabolites that have been studied could be a potential source for future lead candidates. Further study of these molecules may result in creating an antiviral drug to battle the SARS-CoV-2 virus.

Appearance of Verruca Over Linear Verrucous Epidermal Nevus - An Example of Locus Minoris Resistentiae: A Report of Three Cases.

Locus minoris resistentiae (LMR) is a site of the body that offers lesser resistance than the rest of the body to the onset of disease. It can be congenital or acquired. Areas of cutaneous mosaicism such as epidermal nevi can act as congenital LMR, leading to the development of inflammatory skin conditions or skin tumors on these. The occurrence of an infectious condition such as warts over nevi is rare. We report three cases of verrucous epidermal nevi (VENs) with the development of verrruca overlying the nevus later in life. The three patients had VEN on forehead, preauricular, and presternal area, respectively, since birth, with development of a warty lesion overlying these a few months before presenting to us. Skin biopsy and histopathological examination of the linear verrucous lesion were suggestive of VEN with hyperkeratosis, thickened epidermis, and papillomatosis. There was no evidence of epidermolytic hyperkeratosis or increased sebaceous glands in the dermis. Biopsy of the new warty lesion showed findings of verruca in all the patients. With the above findings, a diagnosis of verruca superimposed on linear VEN was made in all the three cases. The warts were removed by electrofulguration. Several acquired skin disorders, including inflammatory dermatoses, adnexal disorders, and neoplasms, have been shown to occur superimposed on epidermal or sebaceous nevus. Ours is probably the first ever description of a wart occurring on VEN.

Erythematous nodules of the hand: a rare site of metastatic breast carcinoma.

Acral cutaneous metastasis is a rare phenomenon. A 38-year-old woman presented with painful lesions in the left hand since 1 month. On examination, multiple painful, erythematous, lobulated plaques and nodules were present over the palmar aspect of the finger tips and thenar eminence. Biopsy of the nodule revealed lobules of small pleomorphic epithelial cells arranged in singles, small nests, cords and small abortive luminal pattern in an abundant mucoid matrix, suggestive of metastatic mucinous carcinoma. Past history revealed that the patient had undergone bilateral mastectomy for carcinoma breast. Diagnosis of cutaneous metastases is based on clinical history and histopathological examination. Identification of the primary tumor is very important for prompt treatment and prognosis. The rarity of pure acral cutaneous metastasis and its possible pathogenetic mechanisms are discussed.

Modulation of catalytic activity in multi-domain protein tyrosine phosphatases.

Signaling mechanisms involving protein tyrosine phosphatases govern several cellular and developmental processes. These enzymes are regulated by several mechanisms which include variation in the catalytic turnover rate based on redox stimuli, subcellular localization or protein-protein interactions. In the case of Receptor Protein Tyrosine Phosphatases (RPTPs) containing two PTP domains, phosphatase activity is localized in their membrane-proximal (D1) domains, while the membrane-distal (D2) domain is believed to play a modulatory role. Here we report our analysis of the influence of the D2 domain on the catalytic activity and substrate specificity of the D1 domain using two Drosophila melanogaster RPTPs as a model system. Biochemical studies reveal contrasting roles for the D2 domain of Drosophila Leukocyte antigen Related (DLAR) and Protein Tyrosine Phosphatase on Drosophila chromosome band 99A (PTP99A). While D2 lowers the catalytic activity of the D1 domain in DLAR, the D2 domain of PTP99A leads to an increase in the catalytic activity of its D1 domain. Substrate specificity, on the other hand, is cumulative, whereby the individual specificities of the D1 and D2 domains contribute to the substrate specificity of these two-domain enzymes. Molecular dynamics simulations on structural models of DLAR and PTP99A reveal a conformational rationale for the experimental observations. These studies reveal that concerted structural changes mediate inter-domain communication resulting in either inhibitory or activating effects of the membrane distal PTP domain on the catalytic activity of the membrane proximal PTP domain.

4-Anilinopyrimido[4',5':4,5]selenolo(2,3-b)quinoline and 4-piperazino pyrimido[4',5':4,5]selenolo(2,3-b)quinoline: new DNA intercalating chromophores with antiproliferative activity.

We have used circular dichroism, hydrodynamic methods, absorbance, and fluorescence titration to study the interaction of 4-anilinopyrimido[4',5':4,5] selenolo (2,3-b)quinoline (APSQ) and 4-piperazinopyrimido[4',5':4,5] selenolo(2,3-b)quinoline (PPSQ) with DNA. The association constants of APSQ and PPSQ were of the order of 10(4)M(-1). The fluorescence properties at ionic strength 0.01M are best fit by the neighbor exclusion model, with K=0.58-9.2 x 10(4)M(-1) and an exclusion parameter of 0.9-6.4 bp. Binding to the GC-rich DNA of Micrococcus lysodeikticus was stronger than the binding to calf thymus DNA, suggest that drug binds preferentially to G+C pairs at low r. CD spectra indicate that stacking of these compounds with DNA induces a strong helicity in the usually disordered structure of this double strand. Viscosity experiments show with sonicated calf thymus DNA with PPSQ an twice increase in slope (m) as that with APSQ. PPSQ increases the T(m) for calf thymus DNA melting by approximately 10 degrees C as binding approaches saturation, with biphasic melting. The cytotoxicities of these compounds on leukemia HL-60, K-562, B16F10 melanoma and Colo-205 are quite similar and inhibition (IC(50)) was in the range of 0.39-9.80 microM. The anticancer efficacy against B16F10 melanoma has provided evidence of major anticancer activity for PPSQ. Single or multiple intraperitonial (i.p.) doses of drug proved high level activity against the subcutaneous (s.c.) grafted B16 melanoma, significantly increase in life span (ILS 139% and 170%). The aim of this study was to analyze the physiochemical properties of these compounds in an attempt to understand its superior biological activity.

A clinical and investigational study of donovanosis.

A clinical and investigational study of 25 cases of Donovanosis was undertaken. The incidence was found to be 1.53% of all STD cases and 2.9% of GUD. M:F ratio was 2.12:1. Incidence was more in unmarried people. Fleshy exuberant type was seen in 88% of cases. Two patients (8%) had extragenital ulcers. Donovan bodies were found in 88%. Pseudo elephantiasis was seen in 8 patients. Biopsy was done in 8 cases and showed acanthosis, plasma cell infiltration and pseudo epitheliomatous hyperplasia. One patient developed squamous cell carcinoma of vulva.

Oral donovanosis.

A 23-year-old male presented with oral ulcers. Tissue smear showed Donovan bodies. The patient was treated with oral tetracycline.