bluuebunny/crossref_metadata_2025 huggingface dataset:
A DENSITY FUNCTIONAL THEORY INVESTIGATION ON THE TAUTOMERS AND CRYSTAL OF 2-DIAZO-4,6-DINITROPHENOL
Authors: JU XUE-HAI , XIAO HE-MING
Published: December 2004

Density functional method was applied to the study of the highly efficient primary explosive 2-diazo-4,6-dinitrophenol (DDNP) in both gaseous tautomers and its bulk state. Two stable tautomers were located. It was found that the structure (I) with open diazo, i.e. with linear CNN, is more stable than that with diazo ring tautomer (II) of DDNP. The structure I is in good agreement with the structure in the bulk. The lattice energy is -89.01 kJ/mol, and this value drops to -83.29 kJ/mol when a 50% correction of the basis set superposition error was adopted. The frontier bands are quite flat. The carbon atoms in DDNP make up the upper valence bands. While the lower conduction bands mainly consist of carbon and diazo N atoms. The bond populations of C–N bonds (both C–Nitro and C–Diazo) are much less than those of the other bonds and the detonation may be initiated through the breakdown of C–N bonds.
Na+/Ca2+ exchange inhibition protects the rat heart from ischemia-reperfusion injury by blocking energy-wasting processes
Authors: Hagihara Hiroji , Yoshikawa Yoshiro , Ohga Yoshimi , Takenaka Chikako , Murata Ken-ya , Taniguchi Shigeki , Takaki Miyako
Published: December 2004

We have recently reported that exposure of rat hearts to high Ca2+ produces a Ca2+ overload-induced contractile failure in rat hearts, which was associated with proteolysis of α-fodrin. We hypothesized that contractile failure after ischemia-reperfusion (I/R) is similar to that after high Ca2+ infusion. To test this hypothesis, we investigated left ventricular (LV) mechanical work and energetics in the cross-circulated rat hearts, which were subjected to 15 min global ischemia and 60 min reperfusion. Sixty minutes after I/R, mean systolic pressure-volume area (PVA; a total mechanical energy per beat) at midrange LV volume (mLVV) (PVAmLVV) was significantly decreased from 5.89 ± 1.55 to 3.83 ± 1.16 mmHg·ml·beat−1·g−1 ( n = 6). Mean myocardial oxygen consumption per beat (Vo2) intercept of (Vo2-PVA linear relation was significantly decreased from 0.21 ± 0.05 to 0.15 ± 0.03 μl O2·beat−1·g−1 without change in its slope. Initial 30-min reperfusion with a Na+/Ca2+ exchanger (NCX) inhibitor KB-R7943 (KBR; 10 μmol/l) significantly reduced the decrease in mean PVAmLVV and Vo2 intercept ( n = 6). Although Vo2 for the Ca2+ handling was finally decreased, it transiently but significantly increased from the control for 10–15 min after I/R. This increase in Vo2 for the Ca2+ handling was completely blocked by KBR, suggesting an inhibition of reverse-mode NCX by KBR. α-Fodrin proteolysis, which was significantly increased after I/R, was also significantly reduced by KBR. Our study shows that the contractile failure after I/R is similar to that after high Ca2+ infusion, although the contribution of reverse-mode NCX to the contractile failure is different. An inhibition of reverse-mode NCX during initial reperfusion protects the heart against reperfusion injury.
Racial Differences of Lens Transparency Properties with Aging and Prevalence of Age-Related Cataract Applying a WHO Classification System
Authors: Sasaki Kazuyuki , Sasaki Hiroshi , Jonasson Fridbert , Kojima Masami , Cheng Hong Ming
Published: December 2004

Purpose: To investigate racial differences of lens transparency properties and the prevalence of lens opacification by age. Methods: Lenses of randomly selected Asian (1,038 Japanese and 517 Singaporeans) and Caucasian (1,045 Icelanders) subjects were evaluated for their lens transparency property (LTP). The prevalence of lens opacification was determined with a newly proposed WHO cataract classification system. Results: LTP increased with aging for all nationalities. Light scattering intensity was significantly higher in the Singaporeans followed by the Icelandic subjects. The prevalence of cortical opacification in Singaporeans was significantly higher than those of the other nationalities up to the age of 60, and the prevalence in Asians was significantly higher than that in Caucasians aged 60–69. Cortical opacification was more prevalent than the other types for both Japanese and Icelanders in their 50s, 60s and 70s. Regarding the central optical zone, the prevalence in the Singaporeans was significantly higher than in the other two groups in their 50s and 60s. The prevalence of nuclear opacification in Singaporeans was markedly higher than those of the two other groups for all ages. Subcapsular cataract was the least prevalent type for all age groups and nationalities; however, the highest prevalence was observed in Singaporeans. Conclusions: Lens transparency decreased with age in the Singaporeans more markedly than in the other two groups. The high prevalence of nuclear opacification in Singaporeans is considered to be due to environmental rather than race-specific factors.
Biomechanical Characterization of Human Amniotic Membrane Preparations for Ocular Surface Reconstruction
Authors: Chuck Roy S. , Graff Jordan M. , Bryant Michael R. , Sweet Paula M.
Published: December 2004

Purpose: To investigate the tensile and elastic properties of both commercially available and experimental human amniotic membrane preparations. Method: Nine preparations of human amniotic membrane were studied. The four dry preparations were untreated (nonirradiated, n = 20), and gamma (n = 25), low-dose (AmbioDry®, Okto Ophtho Inc., Costa Mesa, Calif., USA, n = 20) and high-dose (n = 20) electron beam sterilized. The same dry membranes were moistened with balanced salt solution (n = 20, 34, 20 and 20, respectively). The ninth group consisted of thawed medium-frozen amniotic membrane (AmnioGraft®, Bio-Tissue Inc., Miami, Fla., USA, n = 20). The membranes were cut into thin strips, loaded on a gram range load sensor, and stretched incrementally to the point of rupture. The modulus of elasticity, displacement until rupture and maximum tolerated stress were recorded and compared. Results: The dry preparations exhibited higher moduli of elasticity when compared with the moist samples, with the low-dose electron beam-irradiated samples having the greatest mean modulus of elasticity overall and maintaining a high modulus of elasticity as a moist sample (p < 0.05). Moist nonirradiated preparations and thawed medium-frozen preparations stretched the farthest before rupture and experienced the greatest mean stresses at the point of rupture. While 3 of 4 membranes had greater stretch when moistened as compared to their dry counterparts, there was no difference in the membrane stiffness between dry and moistened low-dose electron beam-irradiated samples (p > 0.8). Conclusions: Low-dose electron beam-irradiated amnion appeared to maintain desirable elastic characteristics in transition from a dry to rehydrated state and may thus provide an easy-to-manipulate transplant tissue for ocular surface reconstruction. Moist nonirradiated and thawed medium-frozen tissues, however, may provide surgical advantages as they required greater forces to rupture.
Presence of the R1748X Mutation in the NF1 Gene in a Brazilian Patient with Ectropion uveae
Authors: Trovó Alessandra B. , Goloni-Bertollo Eny M. , Teixeira Marta F. , Tajara Eloiza H.
Published: December 2004

Congenital ectropion uveae is a rare, nonprogressive anomaly characterized by the presence of iris pigment epithelium on the anterior surface of the iris stroma and is occasionally associated with Rieger’s anomaly, Prader-Willi syndrome and neurofibromatosis type 1 (NF1). The most important complication of ectropion uveae is congenital or juvenile glaucoma. We described a patient with ectropion and the mutation R1748X in the NF1 gene. This is the third report in the literature describing ectropion associated with neurofibromatosis. If this association is confirmed by other authors, the NF1 patients should be examined for the presence of ectropion and, consequently, for the development of glaucoma.
Decreased Lateral Geniculate Nucleus Activation in Retrogeniculate Hemianopia Demonstrated by Functional Magnetic Resonance Imaging at 4 Tesla
Authors: Miki Atsushi , Liu Grant T. , Modestino Edward J. , Bonhomme Gabrielle R. , Liu Chia-Shang J. , Haselgrove John C.
Published: December 2004

Functional magnetic resonance imaging (fMRI) can detect lateral geniculate nucleus (LGN) activation. We studied LGN function in 5 patients with retrogeniculate homonymous hemianopia using fMRI at 4.0 Tesla during binocular visual stimulation. Decreased activation of visual cortex and LGN on the side of the lesion was observed in all 5 patients. These findings suggest that retrogeniculate lesions are associated with decreased activation of the LGN, due to retrograde degeneration or a functional decrease caused by decreased feedback from ipsilateral visual cortex.
Home Hemodialysis and Remote Monitoring: Current Technology, Requirements and Capabilities
Authors: Schlaeper Christian , Diaz-Buxo José A.
Published: December 2004

The changing patterns of utilization of home hemodialysis (HHD) are reviewed with special reference to the factors responsible for its decline and recent revival. Equipment and monitoring systems dedicated to HHD have been recently introduced in response to the demand for more frequent therapies at home. The advantages and disadvantages of novel technology versus time-tested, reliable and versatile platforms are discussed. Despite the significant technological progress achieved, much remains to be done in our quest to make HHD a simple, cost-effective and very safe renal replacement therapy.
Absence of NF-κB Activation by a New Polystyrene-Type Adsorbent Designed for Hemoperfusion
Authors: Menegatti Elisa , Ronco Claudio , Winchester James F. , Dragonetti Antonella , Di Simone Debora , Davit Annalisa , Mengozzi Giulio , Marietti Giorgio , Loduca Giuseppina , Mansouri Morteza , Sancipriano Gian Piero , Sena Luigi M. , Roccatello Dario
Published: December 2004

Aim: The aim of the study was to evaluate biocompatibility of anew polystyrene-type adsorbent (BetaSorbTM) designed for hemoperfusion, using second-level biomolecular analyses. The device has recently been developed to enhance β2-microglobulin removal during hemodialysis. Molecular structure and chemical modifications of the surface beads of this cartridge should prevent exposure of dense hydrophobic surface sites to proteins, and avoid the major drawbacks of previous polystyrene-type adsorbent materials. Methods: Whole blood of healthy donors was incubated in sterile minicolumns packed with BetaSorb Cuprophan, Hemophan, polysulfone and  cellulose acetate. In parallel experiments, whole blood was recirculated for 180 min in a sham dialysis circuit equipped with the study sorbent or Hemophan or polysulfone. Biocompatibility was assessed by means of new biomolecular approaches focused on nuclear factor ĸB (NF-ĸB) activation (assessed by electrophoretic mobility shift assay), TNF-α and IL-1β gene expression (evaluated by real-time PCR), TNF-α and IL-1β production (measured by Western blot assay and ELISA), nitric oxide (NO) generation (detected by electron paramagnetic resonance), free oxygen radical production (by chemiluminescence in a biological assay) and the generation of the complement breakdown product C3d. Results:In coincubation experiments, 5-min contact with any dialysis device, but BetaSorb, was enough to induce activation of NF-ĸB. The amount of TNF-α precursor form was found to increase after 5 min of exposure to each tested polymer, but no traces of mature forms of TNF-α or IL-1β were detected in in vitro experimental conditions using healthy blood. NO and free oxygen radical generation were significantly lower in blood samples exposed to BetaSorb than in control dialysis devices. C3d levels were found to be increased with Hemophan, unaffected by polysulfone, and remarkably decreased with the BetaSorb device. In the sham hemodialysis experiments, NF-ĸB activation and C3d and NO profiles were similar to direct incubation experiments. Compared to basal levels, quantitation of TNF-α and IL-1β mRNA revealed a 15- and 9-fold increase, respectively, in samples exposed to Hemophan for 180 min. Conclusions: The new BetaSorb device not only appears to be highly biocompatible, but shares properties that make it probably able to interfere with the activation of the inflammatory state.
The Use of Placebo in Clinical Trials on Bipolar Disorder: A New Approach for an Old Debate
Authors: Vieta Eduard , Carné Xavier
Published: December 2004

Background: Placebo response is high in bipolar disorder trials. This is a challenge for researchers and an enigma for clinicians. This article will attempt to aid in the comprehension of the ethical questions and methodologies related to the use of placebo in bipolar disorder. Methods: A systematic review of the main computerized data bases (Medline, Embase, Psychlit, Current Contents) was carried out, using the following key words: placebo, bipolar disorder, mania, depression, clinical trial. Results: Placebo has a very important role in the study of bipolar disorders. From a methodological point of view, and given the limitations of non-inferiority designs, the use of placebo is necessary to evaluate the sensitivity of the study and ensure that the drug under investigation is really effective. For this reason, several procedures may be used to satisfactorily solve the ethical objections. Placebo response in bipolar disorder trials is more likely to occur in patients who are mildly ill, bipolar II, mixed-episode, first-episode, rapid cycling, atypical, non-psychotic, substance abusers and medically ill. The use of concomitant medication such as benzodiazepines, a high frequency of visits, a high number of treatment groups and sites, fixed-dose designs, and the concomitant use of psychotherapy are likely to increase placebo response. Conclusion: The subject of the use of placebo in psychiatric clinical trials leads to very relevant ethical, methodological and clinical dilemmas. Many reasons support the use of placebo in acute bipolar studies, whereas in maintenance the length of the treatment with placebo makes the decision more difficult. Ethical concerns can be addressed through operational definitions of outcome measures, add-on and discontinuation designs, early escape strategies, and processes designed to make sure that fully informed consent was fairly obtained. There are a number of clinical and methodological variables that are associated with placebo response.
Randomized Controlled Trial Comparing Brief Dynamic and Supportive Therapy with Waiting List Condition in Minor Depressive Disorders
Authors: Maina Giuseppe , Forner Federica , Bogetto Filippo
Published: December 2004

Background: Although many evidences suggest the presence of specific therapeutic factors in brief dynamic therapy (BDT), few studies have investigated its efficacy in the treatment of depressive disorders in comparison to other psychotherapies. The aim of this study was to determine whether BDT is more effective than brief supportive psychotherapy (BSP) and waiting list condition in the treatment of minor depressive disorders. Method: Thirty patients with primary DSM-IV dysthymic disorder, depressive disorder not otherwise specified or adjustment disorder with depressed mood completed a randomized controlled trial with three treatment groups (BDT, BSP, waiting list condition). A 6-month follow-up was performed for patients treated with both psychotherapeutic approaches. Other psychiatric treatments were not permitted throughout the treatment period and the 6-month follow-up. Symptoms were assessed at baseline, at the end of treatment, and after 6 months of follow-up. Results: Patients treated with both psychotherapeutic approaches showed a significant improvement after treatment in comparison to non-treated controls, but BDT was more effective at follow-up evaluation. Conclusions: BDT is a promising treatment for minor depressive disorders. This study also suggests that BDT is more effective than supportive psychotherapy in improving the long-term outcome of depressive disorders.
Study of β-Adrenoreceptor Antagonistic Activity of DPJ 904 in Rats
Authors: Nandakumar K. , Bansal S.K. , Singh Randhir , Mohite A.J. , Bodhankar S.L. , Jindal D.P. , Coumar Mohane S. , Balaraman R. , Bhardwaj S.H.
Published: December 2004

β-Adrenoreceptor antagonistic activity of a newly synthesized compound was evaluated in vivo by measuring the mean arterial blood pressure and heart rate of urethane-anesthetized rats treated with isoprenaline. In vitro β1-, β2- and β3-antagonism was studied using isolated rat right atria, isolated rat uterus and isolated rat colon preparations, respectively, in comparison to isoprenaline response. DPJ 904 (1, 3 and 10 mg/kg, i.v.) produced dose-dependent hypotensive and bradycardia response in anesthetized rat. DPJ 904 (1, 3 and 10 mg/kg, i.v.) significantly inhibited both the tachycardial effects and hypotensive response induced by isoprenaline. DPJ 904-antagonized isoprenaline induced positive chronotropic effects of isolated rat right atria and a uterine relaxant effect indicating β1- and β2-blockade. The parallel shift to the right of the concentration-response curve of isoprenaline in the presence of DPJ 904 in KCl (30 mmol/l) induced contraction of the rat colon suggesting that DPJ 904 also possessed β3-adrenoreceptor antagonistic activity. The selectivity to β1-adrenoreceptor was nearly 20.5 times greater than to β2-adrenoreceptor. The present study indicates that DPJ 904 possesses β-adrenoreceptor antagonistic activity with slightly more affinity to the β1-adrenoreceptor subtype.
On the Evolutionary Significance of Encephalization in Some Eutherian Mammals: Effects of Adaptive Radiation, Domestication, and Feralization
Authors: Kruska Dieter C.T.
Published: December 2004

Allometries of the brain to body size relationship in eutherian mammals are examined in this study as they can be used for comparative analyses concerning encephalization. In contrast with some modern presentations of this issue, an older concept is revived and expanded through this author’s current study. Three allometries with clearly different slopes are valid and lead to reliable results: interspecific, intraspecific, and ontogenetic allometries. Interspecific allometries follow lines with slope values of 0.56 or 0.63 for larger and smaller species, respectively, and characterize different average encephalization plateaus with rodents and lagomorphs generally more strongly encephalized compared to basal insectivores. Artiodactyls, perissodactyls and carnivores as a whole are again on a higher but rather similar plateau. Several species of carnivores have reached different encephalization levels with respect to their average plateau indicating diverse radiations. A phylogenetic brain size increase from fossil to recent radiations is also evident. Intraspecific allometries have slope values of about 0.25. These are of help in comparing brain sizes of ancestral species with their domesticated relatives. Domestication has generally led to a brain size decrease, but species on higher encephalization plateaus show this trend more strongly than species on a lower level of encephalization. Several brain parts and the sense organs also decrease in size during the domestication process, but vary arbitrarily and to different degrees. Ontogenetic growth allometries are species-specific, but are especially different between altricial and precocial mammals. A very steep 1st phase slope of highly encephalized species is particularly useful for understanding evolutionary and adaptive phenomena. Domesticated mammals that have become feral do not show an increase in brain size despite living many generations in wild habitats.
Stratospheric Influences on MSU-Derived Tropospheric Temperature Trends: A Direct Error Analysis
Authors: Fu Qiang , Johanson Celeste M.
Published: December 2004

Retrievals of tropospheric temperature trends from data of the Microwave Sounding Unit (MSU) are subject to biases related to the strong cooling of the stratosphere during the past few decades. The magnitude of this stratospheric contamination in various retrievals is estimated using stratospheric temperature trend profiles based on observations. It is found that from 1979 to 2001 the stratospheric contribution to the trend of MSU channel-2 brightness temperature is about −0.08 K decade−1, which is consistent with the findings of Fu et al. In the retrieval method developed by Fu et al. based on a linear combination of MSU channels 2 and 4, the stratospheric influence is largely removed, leaving a residual influence of less than ±0.01 K decade−1. This method is also found to be more accurate than the angular scanning retrieval technique of Spencer and Christy to remove the stratospheric contamination.
Clinical Model to Predict Survival in Chemonaive Patients With Advanced Non–Small-Cell Lung Cancer Treated With Third-Generation Chemotherapy Regimens Based on Eastern Cooperative Oncology Group Data
Authors: Hoang Tien , Xu Ronghui , Schiller Joan H. , Bonomi Philip , Johnson David H.
Published: December 2004

Purpose

(1) Identify clinical factors that can be used to predict survival in chemotherapy-naive patients with advanced non–small-cell lung cancer (NSCLC) treated with third-generation chemotherapy regimens, and (2) build a clinical model to predict survival in this patient population.

Patients and Methods

Using data from two randomized, phase III Eastern Cooperative Oncology Group (ECOG) trials (E5592/E1594), we performed univariate and multivariate stepwise Cox regression analyses to identify survival prognostic factors. We used 75% of randomly sampled data to build a prediction model for survival, and the remaining 25% of data to validate the model.

Results

From 1993 to 1999, 1,436 patients with stage IV or IIIB NSCLC with effusion were treated with platinum-based doublets (involving either paclitaxel, docetaxel, or gemcitabine). The response rate and median survival time were 20% and 8.2 months, respectively. One- and 2-year survivals were 33% and 11%, respectively. In multivariate analysis, six independent poor prognostic factors were identified: skin metastasis (hazard ratio [HR], 1.88), lower performance status (ECOG 1 or 2; HR, 1.46), loss of appetite (HR, 1.62), liver metastasis (HR, 1.32), ≥ four metastatic sites (HR, 1.20), and no prior surgery (HR, 1.16). A nomogram using six pretreatment prognostic factors was built to predict 1- and 2-year survival.

Conclusion

Six pretreatment factors can be used to predict survival in chemotherapy-naive NSCLC patients treated with standard chemotherapy. Using our prognostic nomogram, 1- and 2-year survival probability of NSCLC patients can be estimated before treatment. This prognostic model may help clinicians and patients in clinical decision making, as well as investigators in research planning.
Statistical Validation of the EORTC Prognostic Model for Malignant Pleural Mesothelioma Based on Three Consecutive Phase II Trials
Authors: Fennell Dean A. , Parmar Amit , Shamash Jonathan , Evans Marie T. , Sheaff Michael T. , Sylvester Richard , Dhaliwal Kevin , Gower Nicole , Steele Jeremy , Rudd Robin
Published: December 2004

Purpose

Malignant pleural mesothelioma (MPM) carries a poor prognosis due to chemoresistance. The European Organisation for Research and Treatment of Cancer (EORTC) prognostic model was reported to predict survival in MPM. Our retrospective analysis set out to test the validity of the model as a prognostic tool in patients treated in three phase II trials at St Bartholomew’s Hospital (London, United Kingdom) between 1999 and 2003.

Patients and Methods

A total of 145 patients were treated in three phase II trials; vinorelbine (VIN; 70 patients), vinorelbine/oxaliplatin (VO; 26 patients), and irinotecan/cisplatin/mitomycin C (IPM; 49 patients). Two subgroups, high-risk and low-risk, were defined by EORTC prognostic score (EPS). EPS was determined by a five-parameter model incorporating age, sex, histology, probability of diagnosis, and leukocyte count. An EPS cutoff of less than 1.27 (low risk) or more than 1.27 (high risk) was used to stratify Kaplan-Meier survival curves. Each of the EPS variables exhibited either trends or significant stratification of overall survival (OS).

Results

Multivariate analysis confirmed leukocyte count, Eastern Cooperative Oncology Group performance status, and sarcomatous histology as independent prognostic variables. EPS stratified OS in both individual and pooled trial datasets. No association between objective tumor response and EPS classification was identified by multinomial logistic regression. EPS stratified progression-free survival for the VO and IPM cohorts, but not for VIN.

Conclusion

This study validates the EPS system as a robust tool for stratifying small trials into low- and high-risk subgroups. EPS should facilitate patient selection and analysis in randomized clinical trials.
Oxytetracycline Residues in Four Species of Fish after 10-Day Oral Dosing in Feed
Authors: Chen C. Y. , Getchell R. G. , Wooster G. A. , Craigmill A. L. , Bowser P. R.
Published: December 2004

Residues of oxytetracycline (OTC) in serum, liver, and muscle–skin were measured in sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis), Nile tilapia Oreochromis niloticus, summer flounder Paralichthys dentatus, and walleyes Sander vitreus (formerly Stizostedion vitreum). These studies were conducted to compare the time for OTC concentrations to fall below 2.0 μg/g (the current tolerance set by the U.S. Food and Drug Administration (USFDA)) among fish species representing various culture conditions of freshwater and salt water as well as different temperature niches. The sum of mean tissue OTC concentration plus two standard deviations in the edible portion (muscle plus skin) of all fish was below 2.0 μg/g at 11 d postdosing. When possible, depletion data were fitted to a one-compartment pharmacokinetic model. Although temperature niche did not appear to consistently affect residue depletion within species, the warmwater species (sunshine bass and Nile tilapia) often had lower residue concentrations at each time point than did the coolwater species (summer flounder and walleye). For all test species, the period of OTC residue depletion below the USFDA tolerance level was less than the currently established 21-d withdrawal period for OTC in trout Salmo spp., salmon Oncorhynchus spp., and channel catfish Ictalurus punctatus.
Mischsubstratfermentation – ein energetisch begründetes Konzept
Authors: Babel W.
Published: December 2004

On the basis of the combustion enthalpy of microbial biomasses carbon substrates for the aerobically heterotrophic growth of microorganisms can be divided into substrates with energy excess (e.g. ethanol, n‐alkanes) and with energy deficit (or carbon excess, e.g. acetate, glucose). By combining substrates having different carbon energy ratios from both groups in a certain mixing proportion an improvement of the yield coefficients linked to a reduction of the specific heat production (kJ/g dry weight), an increase of the growth rate (h−1) and the velocity of the substrate utilization ought to be possible on condition that the co‐ or auxiliary‐substrate does not cause inhibition or (catabolite‐) repression effects.

There are some examples corroborating the theoretical concept, e.g. the combinations ethanol/sucrose‐Candida utilis, methanol/xylose‐Hansenula polymorpha. In each case the specific growth rate and the yield coefficient on the mixture were higher than on any single substrate of the combination.

Thermochemical methods are suitable for the optimizing the substrate mixing proportion.
Paraffinübergang aus der Kohlenwasserstoffphase zur Hefezelle
Authors: Stichel E. , Glombitza F. , Iske U.
Published: December 2004

The capability of the yeast Lodderomyces elongisporus to utilize solved paraffins in fermentation brothes could be demonstrated. The growth rate of this microorganism in the case of utilization of solved paraffins is higher as the most known dates.

The saturated concentrations of solved hydrocarbons in the fermentation brothes are higher as in real solvent systems.

The part of the solved hydrocarbon is a function of the power input, the diameter of oil drops, the fermentation conditions and the length of the paraffin chain.

The organism growth rate depends on the solved paraffin concentration in the fermentation broth. This fact is one of the reasons for the variability of the consumption coefficients by utilization of paraffins with different chain lenghts.

The results confirm the assumption that the transport of the paraffins from the oil drops to the cells takes place over water soluble phase.
Mathematische Grundlagen der Kinetik der autokatalytischen Reaktion des wachstumsverbundenen Substratabbaues
Authors: Beubler A. , Wolf K.‐H.
Published: December 2004

Auf der Grundlage von hydrodynamischen und reaktionstechnischen Voraussetzungen wird ein dreiphasiges Stoffsystem mit mikrobieller Reaktion auf quasi‐homogene Modelle zurü ckgefü hrt. Mit Hilfe der Michaelis‐Menten‐Kinetik werden Geschwindigkeitsgleichungen fü r die auto katalytische Reaktion des wachstumsverbundenen Substratabbaues hergeleitet, die sich bis auf die Monod‐Kinetik zurü hren lassen. Es wird bewiesen, daß die Geschwindigkeitsgleichungen der mikrobiellen Katalyse denen der heterogenen Gaskatalyse analog sind.
Rheologie von Fermentationslösungen
Authors: Klappach G. , Weichert D.
Published: December 2004

Rheological measurements can give interesting informations for the characterization of fermentation broth, especially concerning the depending of the oxygen transfer rate. Rheological measurements can report decisions for choosing the best reactor type or other process steps e.g. purification and separation.

An advantageous method was used by the combination of a dynamic process‐viscosimeter with the fermenter and the continuous measurement of medium density by X‐ray absorption method.
Bestimmung des geschwindigkeitsbestimmenden Schrittes bei heterogen‐katalytischer Reaktion im hochdispersen Substrat‐Mikroorganismus‐System
Authors: Wolf K.‐H.
Published: December 2004

The problem of the rate‐limiting step of heterogeneous catalytic reactions is explained. For microbiological catalysies in a highdispersial system the partial steps of substance transfer from macroscpace up to the biochemical reaction in the cell (microspace) are generally described and formulated. By means of statistical modells based on the theory of the isotope turbulence the numeric interpretation for the investigation of rate‐limiting step at the fermentation and ripening of beer in bioreactors with enforced turbulence takes place. The rate‐limiting step is the biochemical reaction of the extract degradation, that means kR·tH ≪ 1.
Das Autoselect‐System – ein Automatensystem zur Selektion von Antibiotikaproduzenten. I. Methodische Grundlagen und Umfang des Systems
Authors: Knöll H , Bradler G. , Schicht G. , Forberg W.
Published: December 2004

The methodical principle of an automated selection system for antibiotic producers, the Autoselectsystem, consisting of six machines and a computer is explained. In order to work with this machines the following material is needed: Cassettes with 64 microculture cups for cultivation of colonies on agar, cassettes with glass‐tubes for dilution of samples, and test‐plates with 64 holes for performing the agar diffusion test. The cups, the tubes and holes are arranged in a pattern of 8×8. In a serie of papers the machines will be described.
Das Autoselect‐system – ein Automatensystm zu Selektion von Antibiotikaproduzenten. II. Agarabfüllautomat
Authors: Schicht G. , Bradler G. , Steininger H. , Knöll H.
Published: December 2004

An agardeliverer, one of the machines of the Autoselect‐system is described. This machine allows to pour melted agar automatically into a row of 8 microculture cups of a cassette with 64 cups. By changing the agarcontainer provided for one medium against another container with 8 chambers the machine offers the possibility to deliver 1 to 8 media simultaneously. In this respect the machine gets more and more interest not only for the selection of antibiotic producers, but also for taxonomic, genetic and other studies. Sterile conditions are ensured by sterilizing the head of the machine before starting the work.
Untersuchungen zur Mischung in einem 500 m3‐Rührfermentor‐System bei der mikrobiellen Biomasse‐Synthese unter Einsatz einer Erdöl‐destillat‐Fraktion
Authors: Gentzsch H. , Ringpfeil M.
Published: December 2004

Examination show how far the stirred tank fermenter meets the requirements of multi‐phase systems under conditions of microbiological protein synthesis.

The homogeneity attained by mixing of 4‐phase‐fermentation medium will be influenced by different amounts of material flow of the correspondent process conditions.

Limitation of nitrogen and solved nutrient – and trace salts in culture liquid by unsatisfactorily mixing can be excluded. The solute‐oxygen concentration and homogeneous distribution of solute‐oxygen in the culture liquid are influencing the economy of fermentation.

The homogeneity concerning petroleum distillate‐, biomass‐and air distribution highly depends from biomass content of the fermentation medium.
Energetic and carbon metabolism regulation in lysine producing brevibacterium flavum strains
Authors: Shvinka Y. E. , Viesturs U. E. , Ruklisha M. P. , Baburin L. A. , Galinina N. I.
Published: December 2004

Coordinated regulation of carbon and energetic metabolism enzymes is characteristic of lysine producing strains of Brevibacterium flavum. ATP is the regulating effector and changes in the stationary ATP‐concentration in cells cause certain alternations of enzyme activities in the basic metabolism pathways. The goal of the experiments was the use of the biochemical regulations of methabolism in order to increase the productivity of lysine biosynthesis.

Following results were received:

Activation of TCA‐cycle enzymes is compulsory for intensive lysine biosynthesis.

The most essential of several parallel electron transport pathways in the ETC of Br. flavum is the NADH dependent, cyanid resistant, hydroxamate sensitive oxydation pathway.

Calculations have shown, that the most economical variant is the synthesis of oxalacetate (precursor of lysine) by PEP carboxylation. Therefore strains with elevated PEP‐carboxylase activity synthesize lysine in a more economical way.
Einfluß von Penicillin und seinen Zersetzungsprodukten auf die Biosynthese von L‐Lysin mit Brevibacterium flavum CB
Authors: Bučko M. , Revallová V. , Hano A. , Cunderlíková A. , Mikláš M.
Published: December 2004

In the laboratory scale fermentation the substitution of peanutmeal by a hydrolysate of Penicillium mycelium in the culture medium for production of L‐Lysine with Brevibacterium flavum CB has been testet. The mycelium hydrolysate contains Penicillin and degradation products of Penicillin; therfor the influence of these substances to production of L‐Lysine has been investigated.
Entwicklung und Anwendung einer Methode zur Bestimmung der spezifischen Oberfläche von Hefetrockensubstanz
Authors: Malzahn J. , Klappach G.
Published: December 2004

The knowledge of surface area of microbial biomasses is necessary in connection to mass‐transfer processes for instance extraction process. The method of BRUNAUER, EMMETT and TELLER (BET) based on adsorption processes was adapted to determination of surface area of samples of dry yeast. Comparative investigations and error estimations show the possibility of application and the evidence of this method.
Man‐made microbes and man‐made law
Authors: Gyllenberg H.
Published: December 2004

The Supreme Court of the US in 1980 granted a patent for a strain of Pseudomonas containing two plasmides after genetic manipulation. This is the first case of patenting a living organism. Whereas the patent law of US and of many other countries further more on supports the principle that natural products are not patentable man‐made microorganisms on the other hand fullfil very important crucials of patentability as far as they are new, unobvious, reproducible and useful. The situation arising as the result of this decision is described and the implications and consequenses for the patent law, the taxonomy and the general biological thought are discussed.
Bestimmung von Substratverbrauchskoeffizienten für Paraffinkohlenwasserstoffe
Authors: Glombitza F.
Published: December 2004

The empirical determined constant of 3.14 gram biomass per available electron is a good base for the calculation of minimum substrate consumption coefficients in the aerobic fermentation of paraffins by yeasts.

The analysis of experimental determined specific substrate consumption coefficients and their comparison with the corresponding theoretical values show that the theoretical ones can be reached only if the substrate composition referring to carbon and hydrogen is of optimal composition for all syntheses.
Immobilisierung mikrobieller Zellen und deren Nutzung zur Substratwandlung – Eine Literaturstudie. 1. Fortsetzung
Authors: Berger R.
Published: December 2004

The first supplement of a review on recent literature is given concerning the immobilization of whole microbial cells and their testing for application in product synthesis. It includes the same topics as the first review, essentially, together with the table of the immobilized microbes and the tested reactions of product synthesis or analytical purpose, respectively, with 177 references.
Biosynthesis of polyribonucleotide phosphorylase and polyribonucleotides by E. Coli
Authors: Šmite I. A. , Eglajs V. O. , Rukliša M. P. , Viesturs U. E.
Published: December 2004

The biochemical functions of Polyribonucleotide phosphorylase (PNP‐ase; EC 2.7.7.8) has been studied

The present work was aimed at studying the interrelation between PNP‐ase biosynthesis and RNA content of E. coli cells under various conditions of bacterial growth, obtaining the biomass of E. coli with high PNP‐ase activity as well as to study the possibility of secondary cultivation of E. coli cells for obtaining polyribonucleotides from nucleoside‐5′‐diphosphates

The spcific PNP‐ase activity increases at secondary cultivation, when the medium contains ribonucleoside‐5′‐diphosphates. Besides one may observe an extracellular polycondensation of nucleoside‐5′‐diphosphates

It may be presumed that the PNP‐ase is a multifunctional enzyme whose biological role may be confined to regulating the energetic processes connected with the metabolism of glucose, nucleosidephosphates and orthophosphate in the cells of E. coli.
Traditional food fermentations as industrial resources
Authors: Steinkraus K. H.
Published: December 2004

Asia is rich in resources which can contribute widely to food processing and production over the next 207–50 years as world population reaches 6 billion. The world needs low cost methods of providing nutritious proteinrich meat analogues for its thousands of millions of consumers. The Indonesian tempe fermentation will serve as a model. A bacterium present in commercial tempe can be used to add vitamin B‐12 to other vegetarian foods. Fuel requirements for cooking can be decreased by applying a fungal fermentation of the tempe/ontjom type to legume substrates. The world needs high quality meat‐flavors derived from vegetable protein. The soy sauce (kecap)/miso (tauco) processes and the fish/shrimp sauce and paste processes can be modified to yield a wide variety of meat‐like flavors for use in formulating new foods. The protein content of high starch substrates can be increased by applying the Indonesian tape fermentation. Leavened sour‐dough bread‐like products can be produced without the use of wheat or ryeflours using the Indian idli/dosai fermentation. Coconut protein, if extracted without denaturing, can serve as a valuable base for a new type of puddings and related foods. Finally Asia is an almost endless source of cultures of edible microorganisms that, with further study of their synthetic abilities, particularly regarding amino acids and vitamins, could lead to new industries.
Overproduction of amino acids and the activity of methanol dehydrogenase of protaminobacter thiaminophagus mutants
Authors: Libudzisz Z. , Oberman H. , Malik K.
Published: December 2004

The activity of methanol dehydrogenase of Protaminobacter thiaminophagus ATCC 21371 and its 10 mutants which where able to overproduce amino acids from methanol was studied. It was found that the activity of methanol dehydrogenase depended on the used strain varied from 56.1 to 100.6 mU/mg d. w. of cells. Specific production of amino acids was between 4.3 × 10−7 and 13.0 × 10−7 μg/CFU.

Statistical analysis confirmed expected high positive correlation (r = 0.93) between activity of methanol dehydrogenase and specific production of amino acids.

Based on the measurement of methanol dehydrogenase activity a rapid method of estimation of amino acid production ability of Protaminobacter thiaminophagus mutants was developed.
Sugar compositions of extra‐ and intracellular polysaccharides produced by candida lipolytica (4124) grown on n‐hexadecane
Authors: Jwanny E. W. , Rashad M. M.
Published: December 2004

The free monosaccharide content of C. lipolytica (strain 4 124) cells grown on n‐hexadecane was identified and found to be only glucose. The chromatographic analysis of the hydrolysate of intracellular cell wall polysaccharides indicated the presence of glucose: mannose: galactose: xylose in a ratio of 1 : 1.32 : 1.07 : 0.35.

Paper and dise electrophoresis of extracellular polysaccharid from the culture broth was found to be heterogeneous.

Ethanol fractionation separated it to a major component F (I) 81.99% and a minor one F (II) 13.04%.

Analysis of the major fraction showed that it consisted of galactose and mannose only while the minor polysaccharide consisted of galactose, glucose and mannose.

Thus it was concluded that the predominant sugar in both extracellular and intracellular polysaccharides was mannose. Xylose was detected in the intracellular polysaccharide only.
Formal macroapproach to bioprocessing‐modeling with analogies
Authors: Moser A.
Published: December 2004

A new approach for the investigations of biotechnical processes is presented in this article on the basis of an integrating strategy, incorporating a joint analysis of biological and engineering aspects. Thereby, the experimental work can be carried out on the macroscopic level, taking into account the behavior of bioprocesses from measurements in the liquid phase. Mathematical modeling uses the concept of analogies instead of speculative mechanisms. A predictive character of these “formalkinetics” supplementary to the descriptive nature is achieved with the aid of deductive research methodology. This general theoretical concept is illustrated in the special case of modeling the diauxic growth of yeast. Formalkinetics based on analogies are shown to be not only able to be successfully applied to elucidate bioprocessing but also to form a more realistic and simple approach than pure mechanistic investigations needed for the realization of bioprocessing in technical scale.
Production of neutral and alkaline proteases in batch and chemostat cultures by bacillus mesentericus 76
Authors: Emanuilova E. , Kaimaktchiev A.
Published: December 2004

The kinetics of the bacterial extracellular protease synthesis (neutral and alkaline protease of Bacillus mesentericusstrain 76, R‐form) in batch and chemostat cultures under conditions of glucose limitation were investigated. When the medium was supplemented with casein the production of the proteases was significantly higher. Optimal dilution rates for obtaining of two proteases are fixed. The synthesis of both alkaline and neutral proteases is controlled by catabolite repression and induction.
Methanol oxidation and growth yields in methylotrophic bacteria: A review
Authors: Anthony C.
Published: December 2004

In all bacteria growing on methane or methanol the methanol is oxidised by way of methanol dehydrogenase. This unusual quinoprotein interacts with the electron transport chain at the level of cytochrome c. All methylotrophs having methanol dehydrogenase contain 2 different types of soluble cytochrome c. One of these, but not the other, reacts with methanol dehydrogenase; no intermediate electron carrier is required for this reaction. The P/O ratio for methanol oxidation is 1 although the midpoint redox potential of the methanol/formaldehyde couple suggests that a higher ATP yield might be theoretically possible. Curves are presented that allow the prediction of cell yields, and the effects of altering the system for methanol oxidation, on these cell yields.
Peroxisomes of alkane‐utilizing yeasts metabolic functions and practical aspects
Authors: Fukui S. , Tanaka A.
Published: December 2004

One of the most striking features of alkane‐grown yeast cells is conspicuous appearance of peroxisomes in harmony with a high level of catalase. This unique phenomenon was first demonstrated in the authors′ laboratory, and the metabolic functions of peroxisomes in yeasts utilizing alkanes has been estabilished with intact peroxisomes isolated by density gradient centrifugation. The organelles participate in the degradation of fatty acids derived from alkanes to C2‐units and the synthesis of gluconeogenic intermediates from C2‐units. The abundant appearance of peroxisomes in alkane‐utilizing cells has allowed successful production of several useful enzymes including catalase, D‐amino acid oxidase, uricase, acyl‐CoA oxidase etc. Yeast cells will be an excellent system for investigation the functions and development of peroxisomes because biogenesis of the organelles is induced only by transferring the cells into alkane medium from glucose or ethanol medium.
Criterion for aerobic biological treatment design
Authors: Vavilin V. A.
Published: December 2004

Examples of the aerobic biological reactor treatment design in accordance with generalized model, suggested earlier by the author, are presented. The generalized model is shown to be most adequate to experiments, in a wide range of the level of treatment. The coefficients of the generalized model can be determined graphically. Two simple limiting cases follow from the generalized model corresponding to the rough and high level treatment from complex pollutant. A criterion, which helps to distinguish these two cases, is suggested.
A systematic concept in bioprocess analysis and design
Authors: Moser A.
Published: December 2004

A systematic concept in bioprocess analysis and design is presented according to an integrating strategy as basis for a biotechnological methodology. A comparison illustrates analogies and significant differences between chemical and biological processes.

The study of the interactions between environments and organisms includes influences of physical transport phenomena and also enzyme and metabolic regulations. In both cases the macroscopic principle with a formalkinetic approach is recommended for quantification purposes. The determination of the characteristic‐time‐regime with characteristic rate constants makesit possible to simplify mathematical modeling using the concepts of the rate‐determining‐step and quasistationarity. Finally, guidelines are summarized for the use of unstructured and structured kinetic models.
Extended fed‐batch‐cultivation of exponential growing microorganisms — an analysis for systems with and without outflow
Authors: Neubert M. , J. Bormann E. , Gebhardt I. , Wolleschensky E.
Published: December 2004

The method of extended cultivation was studied mathematical‐analytical by a simple mathematical model. It was reflected on the control algorithm of feeding rate. Because corresponding to the model the substrate is consumed only for the biomass growth, the feeding is to control proportional to the biomass variation. It is shown that the biomass concentration in this case is independent of outflow and approaches a limit value. Relations between biomass growth and feeding rate of limiting substrate are given for all cases. In particular for the cyclie fed batch, it is shown that assuming periodic cycles the cultivation volume at the end of the cycles approaches a maximum value defined only by initial volume, specific growth rate and cycle period.