A thymic carcinoid mimicking acute aortic dissection.

Thymic carcinoids are extremely rare. We present an 80 year old hypertensive patient who presented as an emergency with sudden onset of severe chest and upper back pain raising the suspicion of acute aortic dissection or acute coronary syndrome. Further investigations revealed a carcinoid tumour of thymic origin.

Atomic Force Microscopy and Scanning Electron Microscopy Reveal Genome-dependent Ultrastructure of Seed Surface.

Both scanning electron microscopy (SEM) and contact mode imaging via atomic force microscopy (AFM) have been utilized to elucidate the ultrastructure of mung bean seed surfaces. The results indicate: 1) that AFM is useful in the examination of seed surface ultrastructure ex-vaccuo without the need for additional complex preparative procedures; and 2) that both the cotyledon and seed coat of different strains of mung beans bear specific ultrastructural details unique to each strain. To our knowledge, these are the first AFM images of seed surfaces.

Squamous cell carcinoma of the pleura following bronchopleural fistula.

Squamous metaplasia of the pleura with malignant transformation was observed five months after the development of an empyema and bronchopleural fistula in a 58 year old woman with lingular bronchiectasis.

Ultrastructure of the camel monocyte.

The fine structure of the camel monocytes was studied in order to record its constituents because these informations were missed from the literature. The observations revealed the presence of a few short cisternae of rough endoplasmic reticulum and various forms of vesicles associated with the Golgi complex which were seen near the mitochondria. The distribution of the cytoplasmic organelles seemed to be located adjacent to the main indentation in the nuclei. Camel monocytes were found to possess microvilli of varying length and number. The functional morphology of the above mentioned structures was discussed.

Progress in element analysis on a high-voltage electron microscope.

X-Ray microprobe (XMA) and electron energy-loss (EELS) spectrometers have been installed on the high-voltage electron microscope (HVEM). The probe size has been measured and background reduction is in progress for XMA and EELS as are improvements in electron optics for EELS and sensitivity measurements. XMA is currently useful for qualitative analysis and has been used by several investigators from our laboratory and outside laboratories. However, EELS background levels are still too high for meaningful results to be obtained. Standards suitable for biological specimens are being measured, and a library for quantitative analysis is being compiled.

Tunicamycin-induced shape transformation in rabbit erythrocytes and loss of adhesion in Limnaea embryonic cells.

The effect of tunicamycin (TM), a nucleoside antibiotic, known to inhibit growth of a number of virus, protozoan and metazoan organisms, presumably by intervening in the glycosylation of glycoproteins, has been studied on Limnaea egg cells and rabbit erythrocytes. TM decreases the adhesion of cells in Limnaea morula and, apparently, induces a high degree of membrane permeability probably leading to the extrusion of cytoplasmic material. The effect of TM is more specific on mature rabbit erythrocytes which have no subcellular structure. TM treatment in vitro alters the normal bioconcave disc-shaped erythrocytes successively into crenated discs, crenated spheres, and smooth spheres. This type of transformation is known to be caused by a number of substances but the present report is the first to indicate a nucleoside-containing compound. This irreversible reaction may be attributed to a structural change of the cellular membrane of erythrocytes.

Distinction of benign from malignant ovarian cysts by ultrasound.

The ultrasonic characteristics of benign and malignant cystic ovarian tumours have been reviewed. The value of each of eight different ultrasonic features has been assessed and the specificity of each for confirmation or exclusion of malignancy is indicated. In combination they permit correct differentiation in 91 percent of cases.