Design, fabrication, and characterization of a tissue-equivalent phantom for optical elastography

We suitably adapt the design of a tissue-equivalent phantom used for photoacoustic imaging to construct phantoms for optical elastography. The elastography phantom we consider should have optical properties such as scattering coefficient, scattering anisotropy factor, and refractive index; mechanical properties such as storage and loss modulus; and acoustic properties such as ultrasound velocity, attenuation coefficient, and acoustic impedance to match healthy and diseased tissues. The phantom is made of poly (vinyl alcohol) (PVA) and its mechanical, optical, and acoustic properties are tailored by physical cross-linking effected through subjecting a suitable mix of PVA stock and water to a number of freeze-thaw cycles and by varying the degree of hydrolysis in the PVA stock. The optical, mechanical, and acoustic properties of the samples prepared are measured by employing different techniques. The measured variations in the values of optical scattering coefficient, scattering anisotropy factor, and refractive index and storage modulus are found to be comparable to those in normal and diseased breast tissues. The acoustic properties such as sound speed, acoustic attenuation coefficient, and density are found to be close to the average values reported in the literature for normal breast tissue.     

Primary adenocarcinoma (intestinal type) of nasal septum--a case report

Primary nasal septal adenocarcinoma is a rare lesion. A sporadic case of septal adenocarcinoma in a 22 years old male is being described along with review of literature.     

Electrophoretic analysis of Salmonella typhi and other bacteria

A comparative study involving SDS-PAGE of Salmonella typhi and other Bacteria was conducted. Protoplasmic antigens of Salmonella typhi. Salmonella paratyphi A, Salmonella typhimurium, Proteus sp, Klebsiellas sp. Pseudomonas aeruginosa, Shigella flexneri, Staphylococcus aureus were separated and compared on SDS-PAGE followed by checking of their cross reactivity by gel diffusion using antisera raised against whole cell and lysates of Salmonella typhi. Lines of identity between Salmonella typhi, Salmonella paratyphi A and Salmonella typhimurium were observed. No lines of identity were seen among Salmonella typhi, Pseudomonas aeruginosa and Sfaphylococcus aureus.     

Histopathological and ultrastructural alterations of induced Yersinia enterocolitica infection in mice

Yersinia enterocolitica is an enteric bacterium and infections by this organism are mostly foodborne. It has been implicated to cause enterocolitis, terminal ilitis. diarrhoea, mesenteric lymphadenitis and arthritis in man. Due to paucity of information regarding histopathological and specially ultrastructural alterations in tissues affected, this study was planned with mice as the experimental model. Nine pathogenic Y.enterocoliticaisolates were used to infect 80 albino mice by oral and intraperitoneal route. Pathological alterations were studied by light and electron microscopy. Histopathological examination of intestines showed severe edema, purulent enteritis, goblet cell hyperplasia infiltration of mononuclear cells, thickening of mucosa and necrosis of the tips of villi. Liver showed congestion, hepatocellular degeneration and necrosis, atrophy of hepatocytes and microabcesses. The lungs revealed congestion, edema, haemorrhage and purulent ronchopneumonia, while kidneys showed mild necrotic changes and bacterial emboli in glomeruli. Ultrastructural changes were indicative of mitochondrial degeneration and their loss in kidneys, membranous degeneration with formation of myelin figures in lungs and disorganization, disruption and bleb formation of microvilli in intestines. Y.enterocolitica caused significant histopathological and ultrastructural alterations in experimentally infected mice. Variation in pathogenicity of different strains of Y.enterocolitica was also observed.     

Hepatitis A and acute pancreatitis

Acute pancreatitis in association with acute viral hepatitis A in uncommon. We present the case of a young girl with acute pancreatitis complicating acute viral hepatitis A. The finding of IgM anti-HAV and exclusion of a vast array of other etiologies implicates hepatitis A the cause.