Design and synthesis of a nucleobase functionalized peptide hydrogel: in vitro assessment of anti-inflammatory and wound healing effects.

Over the past several years, a significant increase in the expanding field of biomaterial sciences has been observed due to the development of biocompatible materials based on peptide derivatives that have intrinsic therapeutic potential. In this report, we synthesized nucleobase functionalized peptide derivatives (NPs). Hydrogelation in the synthesized NPs was induced by increasing their hydrophobicity with an aromatic moiety. The aggregation behavior of the NPs was analyzed by performing molecular dynamics simulations and DOSY NMR experiments. We performed circular dichroism (CD), thioflavin-T binding and PXRD to characterize the supramolecular aggregation in the NP1 hydrogel. The mechanical strength of the NP1 hydrogel was tested by performing rheological experiments. TEM and SEM experiments were performed to investigate the morphology of the NP1 hydrogel. The biocompatibility of the newly synthesized NP1 hydrogel was investigated using McCoy and A549 cell lines. The hemolytic activity of the NP1 hydrogel was examined in human blood cells. The stability of the newly formed NP1 hydrogel was examined using proteinase K and α-chymotrypsin. The NP1 hydrogel was used for in vitro wound healing. Western blotting, qRT-PCR and DCFDA assay were performed to determine the anti-inflammatory activity of the NP1 hydrogel. The synthesized NP1 hydrogel also exhibits antibacterial efficacy.

Synthesis and Structural Studies of Nucleobase Functionalized Hydrogels for Controlled Release of Vitamins.

The development of biomolecule-derived biocompatible scaffolds for drug delivery applications is an emerging research area. Herein, we have synthesized a series of nucleobase guanine (G) functionalized amino acid conjugates having different chain lengths to study their molecular self-assembly in the hydrogel state. The gelation properties have been induced by the correct choice of chain lengths of fatty acids present in nucleobase functionalized molecules. The effect of alkali metal cations, pH, and the concentration of nucleobase functionalized amino acid conjugates in the molecular self-assembly process has been explored. The presence of Hoogsteen hydrogen bonding interaction drives the formation of a G-quadruplex functionalized hydrogel. The DOSY nuclear magnetic resonance is also performed to evaluate the self-assembling behavior of the newly formed nucleobase functionalized hydrogel. The nanofibrillar morphology is responsible for the formation of a hydrogel, which has been confirmed by various microscopic experiments. The mechanical behaviors of the hydrogel were evaluated by rheological experiments. The in vitro biostability of the synthesized nucleobase amino acid conjugate is also investigated in the presence of hydrolytic enzymes proteinase K and chymotrypsin. Finally, the nucleobase functionalized hydrogel has been used as a drug delivery platform for the control and sustained pH-responsive release of vitamins B2 and B12. This synthesized nucleobase functionalized hydrogel also exhibits noncytotoxic behavior, which has been evaluated by their in vitro cell viability experiment using HEK 293 and MCF-7 cell lines.

Dynamic Multicomponent Reactions-Directed Self-Assembled G-quadruplex Inherent Antibacterial Hydrogel.

Nowadays, inherent antibacterial hydrogels have gained significant attention due to their utilization against infectious bacteria. Herein, we focus on the development of an injectable, self-healable, dynamic, and G-quadruplex hydrogel with inherent antibacterial activity. The dynamic self-assembled hydrogel is constructed upon multicomponent reactions (MCR) among guanosine, 2-formylphenylboronic acid, and amino acid/peptides in the presence of potassium ions. The role of amino acid/peptides in the formation of the G-quadruplex hydrogel is studied in detail. The G-quadruplex structure is formed via the π-π stacking of G-quartets. The formation of G-quadruplex is investigated by thioflavin T binding assay, CD spectroscopy, and PXRD. The formation of the dynamic imino-boronate bond in the hydrogels is well characterized by temperature-dependent 11B NMR (VT-NMR) and FT-IR spectroscopy. Furthermore, HR-TEM images and rheological experiments reveal the fibrillar networks and viscoelastic property of the hydrogels. The presence of the dynamic imino-boronate ester bonds makes the hydrogel injectable and self-healable in nature. These dynamic G-quadruplex hydrogels show potential antibacterial activity against a series of Gram-positive and Gram-negative bacteria. The hydrogels have been used for the entrapment and sustained release of an anticancer drug doxorubicin over 48 h at different pHs (4.8, 7.4, and 8.5) and temperature without the influence of any external stimuli. Such injectable and self-healable hydrogels could be used in various applications in the field of biomedical science.

Nucleopeptide-Coupled Injectable Bioconjugated Guanosine-Quadruplex Hydrogel with Inherent Antibacterial Activity.

The multicomponent reaction-directed self-assembled hydrogels offer the opportunities to fabricate materials with ubiquitous properties which sometimes are not possible to generate from single components. Therefore, multicomponent-derived hydrogels have enormous applications in biomedical fields, and the number of such systems is increasing day by day. Herein, the multicomponent self-assembly techniques have been employed to develop a biomimetic low-molecular-weight G-quadruplex hydrogel under physiological conditions. The bioconjugation of guanosine, 4-formylphenylboronic acid, and cytosine-functionalized nucleopeptide (NP) is important to generate the multicomponent self-assembled dynamic imino-boronate ester-mediated bioconjugated G-quadruplex hydrogels. Using thioflavin T fluorescence assay, powder X-ray diffraction, and circular dichroism spectroscopic techniques, we confirm the existence of a G-quartet-like structure as the key parameter for the formation of nanofibrillar hydrogels. The multicomponent self-assembled G-quadruplex hydrogel possesses excellent inherent antibacterial activity against a broad range of bacterial species. The in vitro cytocompatibility of the synthesized hydrogel was evaluated on MCF-7 and HEK 293T cell lines to study the biocompatibility of the hydrogel. The proposed injectable, biocompatible, and NP-coupled G-quadruplex hydrogel with inherent antibacterial efficiency holds promising importance to prevent localized bacterial infections.

Sarcoma-like mural nodule in a borderline mucinous tumor of the ovary: A rare entity.

Sarcoma-like mural nodule (SLMN) is a very uncommon and misleading benign entity which may be associated with benign, borderline or malignant mucinous neoplasm of the ovary. It should be distinguished from other malignant mural nodules with sarcoma, carcinosarcoma or anaplastic carcinoma for proper management. We report a rare case of SLMN in a borderline mucinous tumor of the ovary in a 30-year-old lady. In spite of having confusing histopathological features the final diagnosis was made depending on the younger age of the patient, well circumscription of the nodule, absence of vascular invasion and immunohistochemical profile.

Ultrasound-guided aspiration cytology of retroperitoneal masses with histopathological corroboration: A study of 71 cases.

BACKGROUND: Diagnosis of retroperitoneal lesions is one of the most difficult areas in surgical pathology. Both primary and metastatic tumors can grow silently in retroperitoneum before the appearance of clinical signs and symptoms. Guided aspiration cytology has shown a promising role in diagnosis of lesions in this region. AIMS: This study was undertaken to evaluate the reliability of guided fine-needle aspiration cytology (FNAC) in the diagnosis of retroperitoneal masses and to study the spectrum of retroperitoneal lesions in a rural tertiary care hospital. MATERIALS AND METHODS: This study was done on 71 patients presenting with retroperitoneal masses over a period of 20 months in a tertiary care hospital. Ultrasound-guided FNAC was done and the smears were stained by MGG and H and E stains. Histopathological corroboration could be done on all neoplastic lesions along with some non-neoplastic lesions. RESULTS: Out of 71 cases, 48 cases (67.6%) were found to be neoplastic. Malignant tumors (35 cases) were more common than benign ones (13 cases). Malignant lesions were predominantly composed of lesions of lymph node (17 cases i.e. 48.57%) followed by sarcomas (5 cases) and germ cell tumors. Some uncommon retroperitoneal lesions like adrenal myelolipoma, renal angiomyolipoma, Burkitt's lymphoma and adrenocortical carcinoma were found in our study. Guided FNAC could diagnose all the malignant lesions with 100% accuracy except in 2 cases of poorly differentiated carcinoma which came out to be non-Hodgkin lymphoma on subsequent biopsies. CONCLUSION: Guided FNAC is an inexpensive, rapid and reliable method for diagnosis of retroperitoneal masses.