Two different Escherichia coli capsular polysaccharide depolymerases each associated with one of the coliphage phi K5 and phi K20

The Escherichia coli capsular polysaccharides (K antigens) K5 and K20 are known as primary receptors for the coliphage phi K5 and phi K20, respectively. A host range study of the phage revealed that E. coli K5 strains were not only lysed by phi K5 but also by phi K20, and furthermore that the E. coli K95 test strain was attacked by phi K5 in addition to K5 strains. In order to find out whether the phage can degrade the K antigens, the interaction of the phage with isolated polysaccharides was studied. It could be demonstrated that phi K5 was able to depolymerize the K5 and K95 polysaccharides and that phi K20 showed degrading activity towards the antigens K20 and K5. Obviously, each of the phages was associated with two different enzyme systems which enabled them to recognize and depolymerize chemically unrelated polysaccharides.     

One-step purification procedure for UDP-N-acetylmuramyl-peptide murein precursors from Bacillus cereus

A method is described for the rapid isolation of the activated murein precursors UDP-N-acetyl-muramyl-pentapeptide (UDP-MurNAc-pentapeptide) and UDP-MurNAc-tripeptide from Bacillus cereus. After accumulation of the precursors by inhibition of murein synthesis either in the presence of vancomycin (for the pentapeptide precursor) or D-cycloserine (for the tripeptide precursor) the cells were extracted with boiling water. Prior to high pressure liquid chromatography the material was freed from acid precipitable material. UDP-MurNAc-penta- and tripeptide were separated from other components by reversed-phase HPLC on Hypersil ODS using isocratic elution conditions with sodium phosphate buffer. The precursors were obtained with at least 98% purity and a yield of about 50 mumol from a 10-l culture of B. cereus.     

Habitat and population size of the coelacanth Latimeria chalumnae at Grand Comoro

Synopsis In 1987 and 1989 coelacanths were observed for the first time in their natural habitat with the help of submersibles. Coelacanths were found between 150–253 m depth, their preferential depth seems to be around 200 m; the water temperature ranged between 16.5–22.8° C. During the day coelacanths aggregate in small non-aggressive groups in sheltered lava-caves. Caves might be a limiting factor for distribution. At night they leave the caves for hunting by drifting singly along the steep lava slopes. They migrate between different caves located within a large home range covering more than 8 km coastline. Coelacanths are site-attached, some for a period of at least 2 years. Our own observations and earlier catch records show that only the west coast of Grand Comoro is a suitable coelacanth habitat with more structural complexity and prey fish abundance than other coastlines of the island. From our survey we estimated a total coelacanth population off Grand Comoro to be 150–210 individuals; a saturated population would be 370–510 individuals. This small relict population seems to be stable. International protection of coelacanths against commercial interests is needed     

Malignant ascites of serous papillary ovarian adenocarcinoma. An immunocytochemical study of the tumor cells

In 17 malignant peritoneal effusions due to papillary serous adenocarcinoma of the ovary, the reaction patterns of the tumor cells to monoclonal antibodies (MAbs) against surface antigens were studied and compared with the reaction patterns of mesothelial cells in the same effusions. The following surface markers were used with the adhesive slide method: epithelial membrane antigen (EMA), human epithelium-specific cell surface antigen (HEA-125), human endothelial antigen (BMA-120), carcinoembryonic antigen (CEA 3-13), an antibody against natural killer cells and cytotoxic cells (BMA-070), granulocyte antigen (Leu M1) and leukocyte antigen of class I (HLA-1). In all cases, from 30% to 95% of the tumor cells reacted with EMA and HEA-125. Tumor cells showed a positive staining with CEA 3-13 in only five cases. In all cases, from 75% to 95% of the tumor cells reacted positively with BMA-120. The reactivity of a few mesothelial cells with EMA and of all mesothelial cells with BMA-120 did not interfere with the identification of positive tumor cells since the reaction patterns were different. Interestingly, our study demonstrated that BMA-070, an MAb identifying natural killer cells and cytotoxic cells, is also a most useful tumor marker. The same was found to be true for Leu M1, an MAb originally thought to react only with granulocytes. The tumor cells showed a partial or total loss of the expression of HLA-1 reactivity. Since all cases were immunocytochemically positive for tumor cells while conventional cytology was positive in only 13 of the cases, the immunocytochemical analysis of malignant peritoneal effusions due to papillary serous adenocarcinoma of the ovary seems able to improve the cytologic diagnosis of the fluids.     

The value of the immunoperoxidase slide assay in the diagnosis of malignant pleural effusions in breast cancer

Whether immunocytochemical studies of malignant pleural effusions due to breast cancer would increase the diagnostic yield as compared with conventional effusion cytology was examined in 30 cases with biopsy-proven metastatic spread to the pleura. Conventional cytology was performed on air-dried smears as well as on cytocentrifuge preparations stained with the May-Grünwald-Giemsa stain. Immunocytochemistry was performed with monoclonal antibodies against carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA) and human leukocyte antigen (HLA) and the peroxidase-antiperoxidase technique on glass slides after Ficoll-Hypaque centrifugation. By conventional cytology, 13 cases (43%) were positive for malignant cells, 6 cases (20%) were suspicious, and 11 cases (37%) were negative. In marked contrast, all 30 cases were immunocytologically positive for malignancy. Tumor cells in all cases demonstrated a positive reaction for EMA. Some mesothelial cells were also positive for EMA, but their reaction pattern was clearly distinguishable from that of the tumor cells. Twenty-one cases (70%) also showed CEA-positive tumor cells; mesothelial cells never reacted with CEA. Some tumor cells showed a loss of HLA expression. In conclusion, this immunocytologic method can be recommended as a routine procedure for greatly increasing the diagnostic yield of cytology in pleural effusions due to breast cancer.     

Role of special stains in the diagnosis of Pneumocystis carinii infection from bronchial washing specimens in patients with the acquired immune deficiency syndrome

Fifty bronchial washing specimens from 36 patients with acquired immune deficiency syndrome (AIDS) were retrospectively reviewed to assess the sensitivity of the various special stains used to diagnose Pneumocystis carinii. In 76% of the cases, the Diff-Quik stain was positive; it was the easiest and most rapid of the special stains used. The sensitivity was increased to 92%, 96% and 100%, respectively, by also doing cresyl echt violet, Grocott's Gomori methenamine silver and both the cresyl violet and Grocott stains in addition to the Diff-Quik stain. We conclude that the Diff-Quik stain is a fairly reliable and rapid screening procedure for making the diagnosis of Pneumocystis infection in bronchial washings from AIDS patients. The routine Papanicolaou stain gave less sensitive results in the smears of the washing specimens, but does give a markedly improved yield in bronchoalveolar lavage specimens.     

Atresia of the right atrial ostium of the coronary sinus

A case of asymptomatic congenital occlusion of the ostium of the coronary sinus is described. The myocardial venous drainage was maintained via a persistent left superior vena cava as well via ectatic, widened atrial veins of the dorsal wall of the left atrium. The study shows that complete ostial occlusion of the coronary sinus does not reduce cardiac venous drainage. The view of the literature allows a comparison with the comprehensive classification of coronary sinus anomalies.     

Cellular stages in cartilage formation as revealed by morphometry, radioautography and type II collagen immunostaining of the mandibular condyle from weanling rats

The role played by cell addition, cell enlargement, and matrix deposition in the endochondral growth of the condyle was assessed in weanling rats by four approaches making use of the light microscope: morphometry, 3H-thymidine radioautography, 3H-proline radioautography, and immunostaining for the cartilage-specific type II collagen. From the articular surface down, the condyle may be divided into five layers made up of cells embedded in a matrix: 1) the articular layer composed of static cells in a matrix rich in fibers presumed to be of type I collagen, 2) the polymorphic cell layer including the progenitor cells from which arise the cells undergoing endochondral changes, 3) the flattened cell layer in which cells produce a precartilagenous matrix devoid of type II collagen while undergoing differentiation in two stages: a "chondroblast" stage and a short "flattened chondrocyte" stage when intracellular type II collagen elaboration begins, 4) the upper hypertrophic cell layer, in which cells are "typical chondrocytes" that enlarge at a rapid rate, actively produce type II collagen, and deposit it into a cartilagenous matrix, and 5) the lower hypertrophic cell layer, composed of chondrocytes at a stage of terminal enlargement while the cartilagenous matrix is adapting for mineralization. 3H-thymidine radioautographic results indicate that the turnover time of progenitor cells in the polymorphic cell layer is about 2.9 days. The time spent by cells at each stage of development is estimated to be 1.4 days as chondroblasts, 0.5 days as flattened chondrocytes, 2.3 days as the chondrocytes of the upper hypertrophic cell layer, and 1.1 days as those of the lower hypertrophic cell layer. Calculations referring to a 1 x 1-mm square-sided column extending from the articular surface to the zone of vascular invasion provide the daily rate of cell addition (0.0077 mm3), extracellular matrix deposition (0.0127 mm3), and cell enlargement (0.0302 mm3). Hence the respective contribution of the three factors to condyle growth is in a ratio of about 1:1.6:4. This result emphasizes the role played by cell enlargement in the overall growth of the condyle.     

The effect of cherry leaf roll virus infection on the performance of birch pollen and studies on virus replication in germinating pollen

The rates of germ tube elongation in vitro of pollen from cherry leaf roll virus (CLRV)-infected birch (Betula pendula) did not differ significantly from those of pollen from virus-free trees. Differences in percentage germination of pollen collected from trees at different sites were significant but percentages of germination of pollen from virus-infected and virus-free trees did not differ greatly from one another. In vivo, pollen from infected trees germinated on healthy and CLRV-infected stigmas and callose plugs formed in both types of tissues. However, the extent of callose plug formation was greater in the pollen tubes of virus-free grains germinating in infected stigmas than in reciprocal crosses. CLRV coat antigen was detected by ELISA in stigmatic tissue, from healthy trees, on which virus-carrying pollen grains had germinated. Using fluorescein isothiocyanate conjugated to CLRV-specific γ-globulin, viral coat antigen was detected throughout germ tubes from virus-carrying but not virus-free pollen germinating in vitro. Protoplasts released following Driselase digestion of pollen germ tubes from virus-infected trees contained CLRV antigen detectable by ELISA. During germination of virus-infected pollen there was little synthesis of viral coat protein or nucleic acid but, following inoculation with purified virus particles, protoplasts made from healthy germinating pollen produced increasing amounts of CLRV-specific antigen implying that CLRV replicated in this system.