Biomedical subjects

Nidhi Mahajan

Publications and source records attributed to Nidhi Mahajan.

6 recordsLinked to original sources

PubMed2026

Clinical implication of transcriptional dysregulation in the SHH-GLI pathway involving the GLI1 rs61739569 (T>C) variant toward chronic obstructive pulmonary disease (COPD) in North Indians.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) ranks among the leading causes of morbidity and mortality globally. Genomic susceptibility factors are acknowledged as critical modulators of disease variability and progression. The Sonic Hedgehog (SHH) pathway regulates epithelial tissue healing, mucin synthesis, and airway remodeling. GLI1 polymorphic variants may influence the manifestations of COPD. METHODOLOGY: A case-control study was conducted, involving 500 patients with COPD and 500 controls from the North Indian population. We genotyped two GLI1 polymorphisms (rs61739569 (T>C) and rs2228226 (G>C). Logistic regression models were applied to examine the associations between COPD susceptibility and clinical features. RESULTS: rs61739569 and rs2228226 show no association with an increased risk of COPD overall. Nonetheless, rs61739569 exhibited significant phenotype-specific correlations: individuals possessing the CC genotype demonstrated a markedly elevated risk of chronic cough, sputum production, and exacerbations, while displaying a diminished risk of dyspnea and activity limitation. CONCLUSION: Variations in GLI1 may influence the symptoms of COPD, rather than the overall likelihood of developing COPD. The rs61739569 is particularly applicable to mucus-dominant phenotypes, such as those resembling chronic bronchitis. This study suggests that GLI1 signaling exhibits context-dependent functional significance in COPD.

Humans↗

PubMed2006

Bending and radial deformation of lipid tubules on self-assembled thiol monolayers.

Lipid tubules represent a hollow, cylindrical supramolecular structure formed by rolled-up lipid bilayers. We find that the lipid tubules of 1,2-bis(tricosa-10,12-diynoyl)-sn-glycero-3-phosphocholine can be bent into a loopike shape by the shrinking contact line of droplets on self-assembled monolayers (SAMs) of 1-dodecanethiol. The persistence length of individual lipid tubules is estimated to be approximately 41 microm. The radial deformation of the lipid tubules on SAMs is studied under applied load using atomic force microscope. The stiffness of the tubules in the radial direction is found to increase when the number of the lipid bilayers in the tubule wall increases.

Biomechanical Phenomena↗

PubMed2006

Nanoscale ripples in self-assembled lipid tubules.

Self-assembled cylindrical tubules of 1,2-bis(tricosa-10,12-diynoyl)-sn-glycero-3-phosphocholine (DC(8,9)PC) have been studied by atomic force microscopy in both the height and amplitude modes. Nanoscale ripple structures in the cylindrical lipid tubules are clearly resolved in amplitude mode images. The periodicity of the ripples is found to be 200 +/- 30 nm for tubules with diameters in the range from 200 to 650 nm. The angle of the ripples with respect to the equator of the tubules shows a bimodal distribution with centers at approximately 28 degrees and approximately 5 degrees.

Journal Article↗

PubMed2005

Liquid-crystal imaging of molecular-tilt ordering in self-assembled lipid tubules.

Self-assembled cylindrical tubules of chiral phospholipids are interesting supramolecular structures. Understanding the molecular-tilt order is a key step in controlling the size and shape of the tubules and designing new functional materials. The current theories based on the chiral interactions, coupled with molecular tilt, have predicted that the tubules could have both uniform and modulated tilt states. Here, we image the molecular-tilt order in the self-assembled tubules of a chiral phospholipid by using liquid crystals as an optical amplification probe. We demonstrate that the organization of the molecular-tilt azimuth in the lipid tubules can induce an azimuthal orientation in the liquid crystals. Both uniform and modulated tilt states of the lipid tubules are observed after liquid-crystal optical amplification.

Diagnostic Imaging↗

PubMed2005

Two-dimensional ordered arrays of aligned lipid tubules on substrates with microfluidic networks.

Microfluidic networks is a powerful tool for aligning one-dimensional materials over a large area on solid substrates. Here we show that lipid nano- and microtubules can be assembled into two-dimensional (2-D) parallel arrays with controlled separations by combining fluidic alignment with dewetting, which occurs within microchannels. We also demonstrate that lipid tubules can be bent into a well-defined shape at the entrance of the channels by the capillary force. Atomic force microscopy is used to study the structure and stability of the aligned lipid tubules on substrates. The deposition experiments with silica colloidal particles show that the 2-D parallel-aligned tubules can be used as a template to synthesize silica films with controlled morphologies and patterns on substrates in a single-step process.

Journal Article↗

PubMed2005

Patterning polymerized lipid vesicles with soft lithography.

The applications of soft lithography in patterning polymerized lipid vesicles of 1,2-bis(tricosa-10,12-diynoyl)-sn-glycero-3-phosphocholine on glass substrates are reported. We demonstrate that the polymerized vesicles can be used as a high molecular weight ink to be transferred from a PDMS stamp onto a glass substrate to form two-dimensional stripes with a controlled separation. By combining channel flow with dewetting within microfluidic networks, we assemble the polymerized vesicle into three-dimensional stripes and one-dimension lines on glass substrates. Atomic force microscopy shows that these patterned vesicle structures are stable on glass substrates. The simple, stable, and precise immobilization of lipid vesicles on solid substrates will open up the possibility of integrating them in biosensors and microelectronic devices.

Journal Article↗