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The distinction between benign follicular hyperplasia (FH) and follicular lymphoma (FL) is sometimes problematic. We wanted to determine whether the expression of bcl-2 of FH was quantitatively different from that of FL, using surface CD20 expression as a discriminator of the various lymphoid compartments. Lymph node cell suspensions from 12 cases of FH and 17 cases of FL were analyzed by flow cytometry using a combined surface CD20 and intracellular bcl-2 staining. CD20- T cells in FH demonstrated the same bcl-2 expression as the CD20+ mantle cells, but the bright CD20+ germinal center cells showed near absence of bcl-2 expression. In contrast, the neoplastic cells of FL showed greater bcl-2 expression than the T cells of the same tumors and all cell populations of FH. This difference was particularly significant between the neoplastic B cells of FL and the germinal center cells of FH. The combined analysis of CD20 and bcl-2 should be useful for the differential diagnosis between FH and FL and particularly applicable to limited samples or when B-cell clonality is in question. Whether the quantitation of bcl-2 expression can be of further discriminatory value in malignant lymphomas remains to be determined.

The activities of pyruvate kinase (PK), pyruvate: formate-lyase (PFL), pyruvate dehydrogenase (PDH), and citrate synthase (CS) involved in the anaerobic glycerol conversion by Klebsiella pneumoniae were studied in continuous culture under conditions of steady states and sustained oscillations. Both the in vitro and in vivo activities of PK, PFL, and PDH are strongly affected by the substrate concentration and its uptake rate, as is the in vitro activity of CS. The flux from phosphoenolpyruvate to pyruvate is found to be mainly regulated on a genetic level by the synthesis rate of PK, particularly at low substrate concentration and low growth rate. In contrast, the conversion of pyruvate to acetyl-CoA is mainly regulated on a metabolic level by the in vivo activities of PFL and PDH. The ratio of in vitro to in vivo activities is in the range of 1 to 1.5 for PK, 5 to 17 for PFL and 5 to 80 for PDH under the experimental conditions. The regulation of in vivo activity and synthesis of these enzymes is sensitive to fluctuations of culture conditions, leading to oscillations of both the in vitro and in vivo activities. In particular, PFL is strongly affected during oscillations; its average in vitro activity is only about half of its corresponding steady-state value under similar environmental conditions. The average in vitro activities of PDH and PK under oscillations are close to their corresponding steady-state values. In contrast to all other enzymes measured for the glycerol metabolism by K. pneumoniae PFL and PDH are more effectively in vivo utilized under oscillations than under steady state, underlining the peculiar role of pyruvate metabolism in the dynamic responses of the culture. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 60: 617–626, 1998.

The initial steps of glycerol dissimilation and 1,3-propanediol (1,3-PD) formation by Klebsiella pneumoniae anaerobically grown on glycerol were studied by quantifying the in vitro and in vivo activities of enzymes in continuous culture under conditions of steady state and oscillation and during transient phases. The enzymes studied included glycerol dehydrogenase (GDH), glycerol dehydratase (GDHt), and 1,3-propanediol oxidoreductase (PDOR). Three conclusions can be drawn from the steady-state results. First, glycerol concentration in the culture is a key parameter that inversely affects the in vitro activities (concentrations) of all three enzymes, but has a positive effect on their in vivo activities. Growth rate significantly affects the ratio of in vitro and in vivo enzyme activities under low glycerol concentrations, but not under glycerol excess. Second, whereas the flux through the oxidative pathway of glycerol dissimilation is governed mainly by the regulation of in vivo enzyme activity on a metabolic level, the flux through the reductive pathway is largely controlled by the synthesis of enzymes. Third, GDHt is a major rate-liming enzyme for the consumption of glycerol and the formation of 1,3-PD in K. pneumoniae at high glycerol concentrations. Results from oscillating cultures revealed that both in vitro and in vivo activities of the enzymes oscillated. The average values of the in vitro activities during an oscillation cycle agreed well with their corresponding values for nonoscillating cultures under similar environmental conditions. Experiments with step changes in the feed concentration of glycerol demonstrated that growth and product formation are very sensitive to changes of substrate concentration in the culture. This sensitivity is due to the dynamic responses of the genetic and metabolic networks. They should be considered when modeling the dynamics of the culture and attempting to improve the formation of 1,3-PD. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 59: 544–552, 1998.

A multivariable non-linear parameter-adaptive cascade controller for a semi-industrial flocculation plant is described. The static characteristics of the process are approximated by parabolas. The special multivariable problem is solved by a non-linear optimisation using the Lagrange multiplier method. To meet the special requirements due to the non-linear character of the system and the needs for practical application a multivariable testsignal has been designed. To increase the robustness on the one hand, the process identification is switched off after the initialisation of the controller, to conserve a minimum portion of adaptability on the other hand, a feedforward control feature has been installed to correct the gain of the master controller, using several disturbing variables as inputs. Theresults of some semi-industrial scale experiments based on real-world conditions are discussed.

Splitting and renormalisation of doubly-degenerate optical phonons in CecLa1-cF3 single crystals (0?c?1) has been observed in Raman-scattering experiments. The effects depend on the 4f-electron concentrationc, the magnetic field and temperature. A quantitative interpretation is given using a Jahn-Teller type Hamiltonian with only one phenomenological coupling constant.

(Abstracted from Human Reprod2018;33:736–744)Shorter telomeres have been associated with aging, parity, and multiple chronic diseases. A number of studies have reported that women with shorter telomeres are at increased risk of breast, ovarian, and uterine cancer; type 2 diabetes; cardiovascular disease; and atherosclerosis, as well as socio-environmental characteristics and stress.

This article deals with the unique solutions developed for the Hammerfest liquified natural gas project. A liquefied natural gas (LNG) production unit has been equipped with all-electric, variable-speed refrigeration compressor drivers with the ratings of 32 and 65 mW. These compressor strings have been successfully tested by load performance, and their actual service was commenced in autumn 2007. This article focuses on the rotordynamic aspects of the high speed brushless synchronous motors. LNG production involves gaseous methane liquefaction in an extensive refrigeration process. FE calculations of the system is performed to avoid vibration problem at site. [ABSTRACT FROM PUBLISHER]