Biochemical, immunological, and immunocytochemical evidence for the association of chalcone synthase with endoplasmic reticulum membranes.

Chalcone synthase [naringenin-chalcone synthase; malonyl-CoA:4-coumaroyl-CoA malonyltransferase (cyclizing), E.C. 2.3.1.74], the key enzyme of flavonoid pathways that was believed to be soluble, has been localized on ribosome-bearing endoplasmic reticulum membranes in the epidermis of buckwheat (Fagopyrum esculentum M.) hypocotyls. Enzyme activity measurement and immunoblots of buckwheat hypocotyl homogenates that were fractionated on linear sucrose density gradients and developed with a specific chalcone synthase antibody and a 20-nm ImmunoGold conjugate showed the presence of chalcone synthase in fractions enriched in endoplasmic reticulum membranes. The presence of chalcone synthase on these membranes was not caused by nonspecific adsorption or entrapment of proteins. Immunocytochemical investigations with both a 5-nm and a 20-nm ImmunoGold conjugate showed that chalcone synthase was associated with the cytoplasmic face of rough (ribosome bearing) endoplasmic reticulum membranes. Plasma membrane, nucleus, plastids, mitochondria, golgi, and the tonoplast were not labeled. These data are consistent with our earlier described model suggesting that the synthesis of phenylpropanoids and flavonoids takes place partially or fully on membrane-associated enzyme complexes.     

Cat-301 immunoreactivity in the lateral geniculate nucleus and visual cortex of the strabismic amblyopic cat

Purpose: It was investigated whether alterations in neuronal structure and function occasioned by strabismic amblyopia also may be reflected in alterations in the expression on Y type neurons of a Cat-301 antibody sensitive antigen in the lateral geniculate nucleus (LGN) and cortex of our cat model of strabismic amblyopia. Methods/Results: The percentage of positively labelled cells was reduced in LGN laminae that received input from the deviated eye in strabismic amblyopic cats compared with normal cats. In the strabismic cortex, the density of immunopositive neurons was significantly reduced compared with normal, the effect being most pronounced in layer IV Conclusions: Despite previous physiological recordings indicating a decrease in X-cell associated acuity in strabismic amblyopia, the present findings imply that the changes in the early visual experience occasioned by strabismus also produce specific molecular changes in theY neuronal class.     

Aortopulmonary window with patent ductus arteriosus and interrupted aortic arch: A case report

Indian Journal of Thoracic and Cardiovascular Surgery -     

Magnetic resonance in the staging of multiple myeloma]

The authors retrospectively reviewed the MR examinations of 46 patients with clinical and laboratory findings of monoclonal gammopathies (MG). All cases had been submitted to radiographic examination which had shown skeletal involvement in 22 cases and osteoporosis in 11, with rupture of the vertebral body in 3 patients. Scintigraphy had been performed on all patients and CT on 12; 36 patients were subsequently submitted to follow-up (at 6, 12 and 24 months). MR examinations were performed with dedicated coils and standard sequences for the subjects with skeletal localizations on X-ray images. The extant cases, with no radiographic evidence of skeletal involvement, were submitted to MRI of the spine, skull and pelvis. In agreement with clinical and laboratory findings and with follow-up results (in 36 patients), MRI diagnosed MG with no skeletal involvement in 13 cases, osteoporosis in 8 (with rupture of the vertebral body in 2), asymptomatic non-progressive myeloma in 4, solitary myeloma in 3, and multiple myeloma in 18 cases. The good identification of bone marrow and its multiplanarity make MRI the method of choice in the study of patients with suspected or known gammopathies. If compared with other modalities, MRI is more sensitive and accurate in depicting the tumor, its size and relationship to periskeletal tissues, and its possible multifocality. Moreover, the technique has proven to be a valid tool during the follow-up, showing tumor response to therapy.     

Peribursal fat plane of the shoulder: anatomic study and clinical experience

A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency.