Immunocytochemical Staining of Serous Effusions With the Monoclonal Antibody Ber-Ep4

Cytospin preparations were made from 102 serous effusions for immunocytochemical staining using a panel of monoclonal antibodies including a new monoclonal antibody Ber-EP4. On cytological examination, 32 fluids were reported to contain tumour cells consistent with metastatic adenocarcinoma; 66 contained benign cells only and three were reported to contain cells suspicious of malignancy. One effusion contained tumour cells consistent with malignant mesothelioma. Positive staining of the tumour cells with Ber-EP4 was observed in the 32 effusions (100%) which contained adenocarcinoma cells. No staining of the mesothelial cells in these 32 specimens was observed. Carcinoembryonic antigen, epithelial membrane antigen Ca2 and CD15 staining of tumour cells was noted in 53%, 50%, 50% and 9% of these cases, respectively. None of the mesothelial cells in the benign effusions stained with Ber-EP4. Nor did the malignant mesothelial cells in the only case of malignant mesothelioma. These findings suggest that Ber-EP4 is a valuable addition to antibodies available for the differential diagnosis of mesothelial cells and adenocarcinoma cells in serous effusions.     

Viability of onion (Allium cega) seed as influenced by temperature during seed growth

The yield and performance of seeds from crops of winter-hardy, bolting-resistant onion grown at temperatures of 15–16, 18–19 and 22–23°C in 1979, 1980 and 1982 were compared. Yields of seed from crops grown at 22–23°C were lower than those from crops grown at lower temperatures but the seeds ripened between 11 and 32 days earlier. Seeds from crops grown at mean temperatures of above 18°C gave higher percentage germination when imbibed at 30°C than 20°C and they also gave higher percentage seedling emergence than those from crops grown at lower temperatures. Seedlings from seeds produced at mean temperatures above 18°C were heavier than those from seeds of a similar weight but produced at lower temperatures. None of these differences were associated with differences in seed weight, embryo weight or seed dormancy but were positively correlated with differences in seed N-concentration. The differences were also associated with the rate of imbibition of water as high germination, high N-content seeds had a slower rate of imbibition than low germination, low N-content seeds of the same weight.     

An Improved Thermoelectric Probe for Measurements of Apparent Sap Flow Velocity in Intact Plant Stems

Gray, H. R-, Erickson, P. I. and Stone, J. F. 1985. An improvedthermoelectric probe for measurement of apparent sap flow velocityin intact plant stems.—J. exp. Bot. 36: 1320–1324. An improved thermoelectric technique for non-intrusive, non-destructive,and direct sensing of the apparent velocity of sap flow in intactplant stems is presented. The thermoelectric probe was madeof extruded Teflon (DuPont) rod. One of two heating elements,positioned 0.5 cm and 1.0 cm below the temperature sensor, wasused to generate the heat pulse. Heating element selection wasbased on daily environmental conditions. A thermistor touchingthe stem sensed the heat pulse. A second thermistor mountedin dose proximity was used to cancel ambient temperature fluctuations. The improved thermoelectric probe was tested using irrigatedpeanuts (Arachis hypogeae L.). After canopy closure was completein both treatments, apparent sap flow velocity(V_a) was measuredon 17 dat 1200 s intervals between 0830 h and 1630 h apparentsolar time. Successful V_a, measurements were accomplished on94% of the attempts. In order to verify performance on otherspecies with different types of stems, non-replicated V_a, determinationswere also made on cotton (Gossypiwn spp.), prickly sida (Sidasptnosa L.), goosegrass (Eleusine indica (L.) Gaertn.), Palmerpigweed (Amaranthus Palmerii S. Wats.), and cottonwood (Populusdeltoides Marsh.). Success of the probe was due in part to the design of the probewhich included remotely selectable spacing between heater andthermistor and adequate insulation and shielding of the probeand sensed portion of the stem. In addition, acclimatizationof the probe to the operating environment was essential. Key words: Sap velocity, instrumentation     

A Comparison of Two Approaches for Modelling Cassava (Manihot esculenta Crantz.) Crop Growth

Two approaches for modelling the growth and development of cassava,Manihot esculenta Crantz, are described and evaluated. The twomodels differ only in the hypotheses accounting for storageroot growth. In model 1, assimilate allocation to storage rootsis governed by the combined Chanter's (1976: Mathematical modelsin mushroom research and production. PhD Thesis, Universityof Sussex, UK) growth equation; and in model 2 the spill-overhypothesis for assimilate allocation to storage root governsstorage root growth. In both models, canopy photosynthesis generatesthe carbon substrate required for all growth processes. Thegrowth rates of leaves, stems and storage roots are definedby growth equations subject to substrate saturation kinetics.A key feature of both models is that the growth demands of thestem, fibrous roots and storage roots are related to leaf demandrates. Allocation to stems and branches was modelled by meansof a modified logistic growth equation which includes all theparameters and variables (number of nodes, internode lengths,stem density, stem modulus of elasticity and branch tensilestrength) that define the limits of the load bearing capacityof the shoot's supportive structures. The correlation coefficientsfor determination of yield prediction for the models werer =0.898,P =0.0385 (model 1) and r =0.954, P =0.0117 (model 2). For agrowth season of 290 d (after which leaf area index equals zeroand crop growth ceases), both models simulate the sigmoidaltransition from the lag to exponential phase of crop growth.Both models are equally well corroborated by observed data;however, model 1 has greater explanatory power. Copyright 2000Annals of Botany Company Allocation, simulation, model, crop growth, cassava, Manihot esculenta Crantz.