ABSTRACT
Optically transparent immersion liquids with refractive index (nâ¼1.77) to match the sapphire-based aplanatic numerical aperture increasing lens (aNAIL) are necessary for achieving deep 3D imaging with high spatial resolution. We report that antimony tribromide (SbBr3) salt dissolved in liquid diiodomethane (CH2I2) provides a new high refractive index immersion liquid for optics applications. The refractive index is tunable from n=1.74 (pure) to n=1.873 (saturated), by adjusting either salt concentration or temperature; this allows it to match (or even exceed) the refractive index of sapphire. Importantly, the solution gives excellent light transmittance in the ultraviolet to near-infrared range, an improvement over commercially available immersion liquids. This refractive-index-matched immersion liquid formulation has enabled us to develop a sapphire-based aNAIL objective that has both high numerical aperture (NA=1.17) and long working distance (WD=12 mm). This opens up new possibilities for deep 3D imaging with high spatial resolution.
ABSTRACT
OBJECTIVE: Chronic pancreatitis is a gradual, long-term inflammation of the pancreas that results in alteration of its normal structure and function. The study aims to investigate the role of -308 (G/A) polymorphism of TNF-α gene in chronic pancreatitis. MATERIAL AND METHODS: A total of 200 subjects were included in this case-control study. A total of 100 in patients admitted in the Gastroenterology Unit of Gandhi Hospital and Osmania General Hospital, Hyderabad were included in the present study. An equal number of healthy control subjects were randomly selected for the study. The genotyping of TNF-α gene was carried out by tetra-primer ARMS PCR followed by gel electrophoresis. The TNF-α levels were assayed by enzyme-linked immunosorbent assay. RESULTS: A significant variation with respect to the genotypic and allelic distribution in the disease group when compared to control subjects [OR=2.001 (1.33-3.005), p<0.0001**] was observed. Subjects homozygous for the A allele had higher TNF-α levels compared to G allele. CONCLUSION: The present study revealed a significant association of the TNF-α gene promoter polymorphism with chronic pancreatitis. Thus, TNF-α genotype can be considered as one of the biological markers in the etiology of chronic pancreatitis.
