bluuebunny/crossref_metadata_2025 huggingface dataset:
RNA RELOCATION AT MITOSIS IN TRANSFORMED AND TUMORIGENIC HUMAN BREAST EPITHELIAL CELLS
Authors: Mello Maria Luiza S , Barbisan Luis F. , Russo Jose , Vidal Benedicto De C
Published: October 2002

The fate of RNA revealed by metachromatic staining after a critical electrolyte concentration assay using toluidine blue and Mg2+ions as competitors for the substrate dye binding sites was followed at mitosis in human breast epithelial cells transformed by benzo[a]pyrene and transfected with the c‐Ha‐ ras oncogene. The aim was to detect changes in RNA distribution during mitosis in human transformed/tumorigenic cells exhibiting increased nucleolar sizes and rRNA production while in interphase. RNA relocation in association with the mitotic spindle fibers was observed from metaphase to telophase not to vary in all the cell lines studied. RNA‐containing nucleolus‐like bodies persistent during mitosis were found to decrease in frequency in the transformed and tumorigenic cells in comparison with control non‐transformed cells simultaneously to the previously reported increase in nucleolar areas for the same cells while in interphase. It is suggested that an improved use of RNA transcripts has been developed with cell transformation and tumorigenesis in this particular model.
REDUCED VIABILITY OF VASCULAR ENDOTHELIAL CELLS BY HIGH CONCENTRATION OF ASCORBIC ACID IN VITREOUS HUMOR
Authors: Hanashima Carina , Namiki Hideo
Published: October 2002

Normal mammalian vitreous humor maintains its avascularity after regression of hyaloid vessels. Neovascularization in adults is only detected under pathological conditions which suggests that antiangiogenic factors are present in the vitreous humor. To elucidate the mechanism of vitreal angiogenic inhibition, we investigated the effect of vitreous humor on cultured vascular endothelial cells. When bovine aortic endothelial cells were cultured in the presence of bovine vitreous humor in medium, a decrease in cell viability was observed within 24h. Ascorbic acid from vitreous humor has been identified as a cell death inducing factor with high performance liquid chromatography (HPLC) and molecular mass analysis. Ascorbic acid reduced endothelial cell viability at concentrations normally present in vitreous humor. This effect was completely inhibited by antioxidants, N‐acetylcysteine and catalase. Amongst the ascorbic acid derivatives tested, ascorbic acid 2‐phosphate did not induce cell death, suggesting that the production of ascorbyl radical is required for induction of cell death. Furthermore, capillary formation in three‐dimensional collagen gel cultures characteristic of vascular endothelial cells were disrupted in the presence of ascorbic acid. Since ascorbic acid is highly concentrated in ocular tissues, especially in vitreous humor, it may function as a neovascularization inhibitor.
COMPARISON OF THE GROWTH PATTERNS AND MORPHOLOGICAL CHARACTERISTICS OF MECHANICALLY AND ENZYMATICALLY ISOLATED FALLOPIAN TUBE EPITHELIAL CELLS
Authors: Sattar Saeeda , Abbas Babar , Jones Lucy , Saridogan Ertan , Mahmood Tariq , Mehta Jayant , Djahanbakhch Ovrang
Published: October 2002

This study set out to compare the growth patterns and morphological characteristics of human fallopian tube epithelial cells isolated: (1) mechanically; and (2) enzymatically. Cells were cultured in medium supplemented with fetal bovine serum and antibiotics and their epithelial nature was established by immunocytochemistry for cytokeratins. Primary cultures were polygonal in shape with centrally located nuclei, irrespective of the isolation method. Cells isolated enzymatically exhibited a higher growth rate, but the survival rate was poor after more than 2–3 passages. Mechanical isolation gave a lower yield of cells, but had a higher survival rate when sub‐cultured, even beyond 8 passages. Thus, mechanically isolated cells might be useful for longer term cultures, whereas enzymatically isolated cells are best only for short‐term work.
CISPLATIN INDUCES MODIFICATIONS IN THE DEVELOPMENT OF CELL SURFACE PATTERNS OF CILIATES
Authors: Machwe Swati , Arora Seema , Gupta Renu , Sapra G. R.
Published: October 2002

Cisplatin [cis ‐dichlorodiammineplatinum (II)] brings about significant quantitative modifications in the development of cell surface patterns in two unrelated ciliates: Stylonychia and Tetrahymena. Cells cultured in the presence of cisplatin exhibit the formation of supernumerary surface structures in the form of extra cilia/cirri (fused cilia) and other organized ciliary organelles. The metal‐induced formation of extra primordia and their differentiation into supernumerary ciliary structures is governed by the normal rules of development. Additional structures are accommodated within the framework of a defined pattern, suggesting the existence of an overall global control of pattern formation. The modified pattern is rectified to its normal state during post‐treatment fission cycles, suggesting the role of the cell membrane in correcting developmental errors.
MOSQUITO LARVAE SOLUBLE FRACTIONS INDUCE DNA SYNTHESIS ALTERATIONS ON HUMAN MONONUCLEAR CELLS
Authors: Ronderos J. R. , Salas M. A. , Rimoldi O. J.
Published: October 2002

Mosquito larvae soluble fractions obtained by molecular exclusion chromatography altered the mitotic rate of several epithelial cell populations in hepatectomised mice, as well as the proliferation of human mononuclear cells (MNC), stimulating or inhibiting them depending on the fraction and dose applied. The effect was also thermolabile, suggesting a proteic nature of the compounds involved. Analysis of cell viability after culture indicated that the extract did not have lethal toxic effects. One fraction with a molecular weight ranging between 12–80kDa caused only an inhibitory effect. In the present study, we performed further characterisation of this fraction by assaying the effect of new fractions obtained from this one, by the use of a column with a lower molecular weight exclusion range. Assays were performed on the proliferation of adult human MNCs. Our results showed that two out of four of the sub‐fractions analysed, with a MW of about 70 and 17kDa, caused a dose‐dependent response, either inhibiting or stimulating MNC proliferation respectively.
DEFINITIVE EXPRESSION OF C‐MOS IN LATE MEIOTIC PROPHASE LEADS TO PHOSPHORYLATION OF A 34KDA PROTEIN IN CULTURED RAT SPERMATOCYTES
Authors: Nagao Yosinobu
Published: October 2002

To investigate the role of c‐mos in rat spermatogenesis, expression of c‐mos, MAP kinase kinase (MAPKK), MAP kinase (MAPK), cdc2 and protein kinase A (PKA) by spermatogenic cell culture of 14 day‐old rats was examined. MAPKK and PKA expressions were constitutive, whereas the expression of MAPK and cdc2 in spermatogonia initially decreased, but later increased on meiotic maturation of spermatocytes. c‐mos expression was definitive of late meiotic prophase. c‐mos immunoprecipitates prepared from the c‐mos‐enriched fraction (pI9.0–9.6) could form complex(es) in the cultured spermatogenic cell lysates.In vitro phosphorylation of the c‐mos immune complexes revealed a 34 kDa protein that was phosphorylated at serine and threonine residues as a target of the c‐mos signal. Its pI value was 4.4–4.5, and cdc2 was not detected, making it different from cdc2 (p34). These results suggest that the phosphorylation of the 34kDa protein by the c‐mos signal may play a crucial role in the meiotic division of rat spermatocytes.
UNUSUAL CYTOLOGICAL PATTERNS OF MICROSPOROGENESIS IN BRACHIARIA DECUMBENS: ABNORMALITIES IN SPINDLE AND DEFECTIVE CYTOKINESIS CAUSING PRECOCIOUS CELLULARIZATION
Authors: Mendes‐Bonato Andréa Beatriz , Filho Roberto Gargione Junqueira , Pagliarini Maria Suely , Do Valle Borges Cacilda , De Penteado Maria Isabel Oliveira
Published: October 2002

Cytogenetic studies carried out in the tetraploid accession BRA001068 of Brachiaria decumbens, also known as cv. Basilisk, revealed an unusual pattern of microsporogenesis. The spindle in metaphase I and anaphase I became heavily stained with propionic carmine. In telophase I, the interzonal microtubules continued to be intensely stained, and during the phragmoplast formation the fibers were pushed to the cell wall, persisting until prophase II, even after cytokinesis. Due to its tetraploid condition, the accession presented many cells with precocious chromosome migration to the poles in metaphase I and laggards in anaphase I that gave rise to micronuclei in telophase I. While in other polyploid accessions of Brachiaria micronuclei remained in this condition until the second cytokinesis, the micronuclei in this accession organized their own spindle in the second division. In several microsporocytes, the micronuclei with their minispindle were divided further into microcytes by additional cytokinesis. Some curious planes of cytokinesis were found in some cells, with partitioning of cytoplasm into cells of irregular shape. The result consisted of a high frequency of abnormal products of meiosis. Quadrivalents were observed in diakinesis at low frequency, which suggests a segmental allotetraploid and the inability of both genomes to co‐ordinate their activities, leading to multiple spindle and precocious cellularization. In spite of abnormal meiotic products reducing pollen fertility, seed production was normal. Enough normal pollen was available to fertilize the central‐cell nucleus of the embryo sac and produce normal endosperm in this pseudogamous aposporous apomictic accession.
MOLECULAR IDENTIFICATION OF PpHDAC1, THE FIRST HISTONE DEACETYLASE FROM THE SLIME MOLD PHYSARUM POLYCEPHALUM
Authors: Brandtner Eva‐Maria , Lechner Thomas , Loidl Peter , Lusser Alexandra
Published: October 2002

The dynamic state of post‐translational acetylation of eukaryotic histones is maintained by histone acetyltransferases (HATs) and histone deacetylases (HDACs). HATs and HDACs have been shown to be components of various regulatory protein complexes in the cell. Their enzymatic activities, intracellular localization and substrate specificities are regulated in a complex, cell cycle related manner. In the myxomycete Physarum polycephalum multiple HATs and HDACs can be distinguished in biochemical terms and they exhibit dynamic activity patterns depending on the cell cycle stage. Here we report on the cloning of the first P. polycephalum HDAC (PpHDAC1) related to the S. cerevisiae Rpd3 protein. The expression pattern of PpHDAC1 mRNA was analysed at different time points of the cell cycle and found to be largely constant. Treatment of macroplasmodia with the HDAC inhibitor trichostatin A at several cell cycle stages resulted in a significant delay in entry into mitosis of treated versus untreated plasmodia. No effect of TSA treatment could be observed on PpHDAC1 expression itself.
Pollen Evidence of Changing Holocene Monsoon Climate in Sichuan Province, China
Authors: Jarvis Devra I.
Published: October 2002

Pollen evidence from Lake Shayema, Mianning County, was obtained to examine postglacial vegetation and climatic change in southwestern Sichuan, China. The sclerophyllous character of the region's warm temperate vegetation today is a reflection of extreme drought in spring before the onset of the Asian monsoons. The pollen record displays several changes in the vegetation over the last 11,000 yr. From 11,000 to 9100 yr B.P., cold-tolerant species, such as Abies , Betula, and deciduous oaks, dominated the vegetation. Between 9100 and 7800 yr B.P., the abundance of deciduous oaks decreased and evergreen oaks increased, as did Tsuga and mesic deciduous species. This change suggests a warming climate with increased precipitation. From 7800 to 4000 yr B.P., sclerophyllous species increased at the expense of mesic deciduous species, an indication that precipitation was becoming more seasonal. Except for increased disturbance starting ca. 1000 yr B.P., the predominance of sclerophyllous vegetation continued until today. The pollen results are compatible with proposed global circulation hypotheses of a strengthened monsoon system during the early to mid Holocene.
Holocene Deglaciation, Sea-Level Change, and the Emergence of the Windmill Islands, Budd Coast, Antarctica
Authors: Goodwin Ian D.
Published: October 2002

A Holocene deglaciation sequence for the Windmill Islands was determined from the 14C age of raised marine shorelines, lakebottom sediments, and Adelie penguin remains found in abandoned rookeries. A north-south gradient in the elevation of the upper marine limit was observed, with the highest marine limit (31-32 m) observed on Browning Peninsula and Hull Island at the southern edge of the islands. Correspondingly, the southern islands were found to have been deglaciated by 8000 (corr.) yr B.P. while the northern islands were deglaciated by 5500 (corr.) yr B.P. Isostatic uplift rates were calculated as 0.5 to 0.6 m/100 yr, with an estimated total uplift of around 53 m which indicates late Pleistocene ice sheet thicknesses of 200 and 400 m over the islands and adjacent Petersen Bank, respectively. The margin of the Late Pleistocene grounded ice sheet extended an estimated 8-15 km offshore which coincides with the location of the 200 m isobath.
Late Weichselian Glaciation of the Russian High Arctic
Authors: Siegert Martin J. , Dowdeswell Julian A. , Melles Martin
Published: October 2002

A numerical ice-sheet model was used to reconstruct the Late Weichselian glaciation of the Eurasian High Arctic, between Franz Josef Land and Severnaya Zemlya. An ice sheet was developed over the entire Eurasian High Arctic so that ice flow from the central Barents and Kara seas toward the northern Russian Arctic could be accounted for. An inverse approach to modeling was utilized, where ice-sheet results were forced to be compatible with geological information indicating ice-free conditions over the Taymyr Peninsula during the Late Weichselian. The model indicates complete glaciation of the Barents and Kara seas and predicts a “maximum-sized” ice sheet for the Late Weichselian Russian High Arctic. In this scenario, full-glacial conditions are characterized by a 1500-m-thick ice mass over the Barents Sea, from which ice flowed to the north and west within several bathymetric troughs as large ice streams. In contrast to this reconstruction, a “minimum” model of glaciation involves restricted glaciation in the Kara Sea, where the ice thickness is only 300 m in the south and which is free of ice in the north across Severnaya Zemlya. Our maximum reconstruction is compatible with geological information that indicates complete glaciation of the Barents Sea. However, geological data from Severnaya Zemlya suggest our minimum model is more relevant further east. This, in turn, implies a strong paleoclimatic gradient to colder and drier conditions eastward across the Eurasian Arctic during the Late Weichselian.
Last Glacial Maximum to Early Holocene Wind Strength in the Mid-latitudes of the Southern Hemisphere from Aeolian Dust in the Tasman Sea
Authors: Hesse Paul P. , McTainsh Grant H.
Published: October 2002

Dust transported by Southern Hemisphere mid-latitude westerly winds from Australia and deposited in the Tasman Sea shows no evidence for stronger winds during the last glacial maximum (LGM), compared to the Holocene. Features of the particle-size distributions of the dust do, however, indicate enhanced dry deposition of dust in the LGM changing to rainfall scavenging during deglaciation and the early Holocene as climate ameliorated. From these results it appears that activation of desert dunefields over 40% of Australia during the LGM was the result of a reduction in stabilizing vegetation and more frequent episodes of sand movement rather than of increased wind strength. The LGM climate of inland Australia must have been considerably more stressful for plants as a result of lower precipitation and/or carbon dioxide stress to achieve the implied levels of surface destabilization. Enhanced atmospheric dust loads in the Southern Hemisphere and deposition over Antarctica were most likely the result of greatly expanded source areas in the mid-latitude southern continents and a weaker hydrological cycle rather than greater entrainment or more efficient transport by stronger winds. During the LGM wind strength appears to have varied regionally, and predominantly in high latitudes, rather than uniformly for all zonal winds.
Lake Levels and Sequence Stratigraphy of Lake Lisan, the Late Pleistocene Precursor of the Dead Sea
Authors: Bartov Yuval , Stein Mordechai , Enzel Yehouda , Agnon Amotz , Reches Ze'ev
Published: October 2002

Lake Lisan, the late Pleistocene precursor of the Dead Sea, existed from ∼70,000 to 15,000 yr B.P. It evolved through frequent water-level fluctuations, which reflected the regional hydrological and climatic conditions. We determined the water level of the lake for the time interval ∼55,000–15,000 cal yr B.P. by mapping offshore, nearshore, and fan-delta sediments; by application of sequence stratigraphy methods; and by dating with radiocarbon and U-series methods. During the studied time interval the lake-level fluctuated between ∼340 and 160 m below mean sea level (msl). Between 55,000 and 30,000 cal yr B.P. the lake evolved through short-term fluctuations around 280–290 m below msl, punctuated (at 48,000–43,000 cal yr B.P.) by a drop event to at least 340 m below msl. At ∼27,000 cal yr B.P. the lake began to rise sharply, reaching its maximum elevation of about 164 m below msl between 26,000 and 23,000 cal yr B.P., then it began dropping and reached 300 m below msl at ∼15,000 cal yr B.P. During the Holocene the lake, corresponding to the present Dead Sea, stabilized at ca. 400 m below msl with minor fluctuations. The hypsometric curve of the basin indicates that large changes in lake area are expected at above 403 and 385 m below msl. At these elevations the lake level is buffered. Lake Lisan was always higher than 380 m below msl, indicating a significantly large water contribution to the basin. The long and repetitious periods of stabilization at 280–290 m below msl during Lake Lisan time indicate hydrological control combined with the existence of a physical sill at this elevation. Crossing this sill could not have been achieved without a dramatic increase in the total water input to the lake, as occurred during the fast and intense lake rise from ∼280 to 160 m below msl at ∼27,000 cal yr B.P.
Effect of the use of vital dye, lymphoscintigraphy, or a combination for axillary lymphatic mapping and sentinel node biopsy in breast cancer
Authors: d’Eredita Giovanni , Serio Gabriella , Mele Marino , Giardina Carmela , Martellotta Martino , Ferrarese Filippo
Published: October 2002

Axillary dissection in patients with breast cancer is associated with significant morbidity. Because 85% of the patients with a cancer ≤1 cm have negative axillary nodal status, axillary dissection in these patients is only a staging procedure. A study of the sentinel lymph node (SLN) biopsy has been developed to determine axillary nodal status by means of a minimally invasive procedure. The aim of our study was to estimate the degree of reliability for identifying the SLN using a vital dye or lymphoscintigraphy, or a combination of the two. From January 1999 to May 2000 a series of 60 patients with breast cancer were evaluated for enrollment in the study. For the mapping procedure, lymphoscintigraphy in combination with injection of vital blue dye was performed in 24 patients, and vital dye alone was utilized in 36. Complete axillary dissection was performed in all patients after SLN biopsy. The mapping procedure was possible in 59 cases (98.3%). The SLNs were positive in 19 patients (32.2%) and negative in 40; in 38 of the 40 patients all axillary nodes were negative. There was concordance in 57 of 59 cases (96.6%). The false‐negative rate was 5% (2/40). The overall sensitivity of the SLN biopsy was 90.4% (19/21), with a negative predictive value of 95% (38/40). Our results indicate that SLN biopsy guided by a gamma probe in combination with vital dye can identify a negative axilla with high accuracy. We conclude that the use of both techniques produces an optimal result, as they are complementanry.
Fluctuating environments and the role of mutation in maintaining quantitative genetic variation
Authors: BÜRGER REINHARD , GIMELFARB ALEXANDER
Published: September 2002

We study a class of genetic models in which a quantitative trait determined by several additive loci is subject to temporally fluctuating selection. Selection on the trait is assumed to be stabilizing but with an optimum that varies periodically and might be perturbed stochastically. The population mates at random, is infinitely large and has discrete generations. We pursue a statistical and numerical approach, covering a wide range of ecological and genetic parameters, to determine the potential of fluctuating environments to maintain quantitative genetic variation. Whereas, in contrast to some recent claims, this potential seems to be rather limited in the absence of recurrent mutation, fluctuating environments might, in combination with it, often generate high levels of additive genetic variation. We investigate how the genetic variation maintained depends on the ecological parameters and on the underlying genetics.
Genetic analysis of an intersex allele (ix5) that regulates sexual phenotype of both female and male Drosophila melanogaster
Authors: ACHARYYA M. , CHATTERJEE R. N.
Published: September 2002

An allele of intersex (ix5) of Drosophila melanogaster has been characterized. The genetic analysis of the allele demonstrated that like other point mutations of ix, the ix5 allele also transformed diplo-X individuals into intersexes. The ix5 mutation also affects the arrangement of sex comb bristles on the forelegs of males, although they had morphologically nearly normal male genitalia. They often fail to display a sustained pattern of courtship activity when tested. Orcein-stained squash preparations of testes from ix5 males revealed a defect in spermatogenesis. Our results, taken together with those of McRobert & Tompkins (1985), indicate that the ix+ gene also functions in male sex determination.
The use of frozen semen to minimize inbreeding in small populations
Authors: SONESSON ANNA K. , GODDARD MIKE E. , MEUWISSEN THEO H. E.
Published: September 2002

In this study, we compared the average coancestry and inbreeding levels for two genetic conservation schemes in which frozen semen from a gene bank is used to reduce the inbreeding in a live population. For a simple scheme in which only semen of generation-0 (G0) sires is used, the level of inbreeding asymptotes to 1/(2N), where N is the number of newborn sires in the base generation and rate of inbreeding goes to zero. However, when only sires of G0 are selected, all genes will eventually descend from the founder sires and all genes from the founder dams are lost. We propose an alternative scheme in which N sires from generation 1 (G1), as well as the N sires from G0, have semen conserved, and the semen of G0 and G1 sires is used for dams of odd and even generation numbers, respectively. With this scheme, the level of inbreeding asymptotes to 1/(3N) and the genes of founder dams are also conserved, because 50% of the genes of sires of G1 are derived from the founder dams. A computer simulation study shows that this is the optimum design to minimize inbreeding, even if semen from later generations is available.
Inheritance of litter size at birth in the Brazilian grass mouse (Akodon cursor, Sigmodontinae, Rodentia)
Authors: AULCHENKO YU. S. , ARARIPE L. O. , D'ANDREA P. S. , SHISHKIN A. A. , CERQUEIRA R. , BORODIN P. M. , AXENOVICH T. I.
Published: September 2002

By means of complex segregation analysis we studied the inheritance of litter size in two large pedigrees of captive-bred colonies of the Brazilian grass mouse Akodon cursor. Genetic analysis has revealed a highly significant influence of genetic factors on the variation of litter size (heritability, h2, was estimated as 0.44). The inheritance followed the classical polygene model: neither the major-gene model nor the polygene with unequal contribution model described the data significantly better.
Abstracts of papers presented at the twelfth Genetical Society's Mammalian Genetics and Development Workshop held at the Institute of Child Health, University College London on 5–7 December 2001
Authors: COPP ANDREW J. , FISHER ELIZABETH M. C.
Published: September 2002

Sponsored by: The Genetics Society, Promega (UK) Ltd and B&K Universal Group Ltd
A statistical test for the difference in the amounts of DNA variation between two populations
Authors: INNAN HIDEKI , TAJIMA FUMIO
Published: September 2002

A statistical test for the difference in the amounts of DNA variation between two populations is developed. The test statistic involves the covariance of the amount of variation between two populations, which is given by a function of their divergence time, T0. Accordingly, the power (rejection probability) of the test depends on T0. In this article, T0 is treated as unknown because it is very difficult to estimate. The test is most conservative when T0 = ∞ is assumed because the covariance is zero. If T0 = 0 is assumed, the largest value of the rejection probability is obtained. Thus, the test provides a range of rejection probability unless we have a reliable estimate of T0. The test is applied to the PgiC region in three mustard species: Leavenworthia stylosa, L. crassa and L. uniflora. The results of our test show that the level of variation in L. stylosa is significantly higher than those in the other species.
Enabling Population and Quantitative Genomics
Authors: GIBSON GREG , MACKAY TRUDY F. C.
Published: September 2002

Dissection of quantitative traits to the nucleotide level requires phenotypic and genotypic analysis of traits on a genome scale. Here we discuss the set of community-wide genetic and molecular resources, including panels of specific types of inbred lines and high density resequencing and SNP detection, that will facilitate such studies.
Effect of bile components on the surface properties of bifidobacteria
Authors: KOCIUBINSKI GUILLERMO , GÓMEZ ZAVAGLIA ANDREA , PÉREZ PABLO F. , DISALVO EDGARDO A. , DE ANTONI GRACIELA L.
Published: September 2002

The action of bile on bifidobacteria was studied by measuring changes in zeta potential, hydrophobicity and adherence to enterocyte-like cells in vitro. Highly hydrophobic strains shocked with bile displayed more negative zeta potential values and a decrease in adherence. When a non-hydrophobic non-adherent strain (CIDCA 5324) was shocked with bile, an increase in hydrophobicity was observed. However, no changes of zeta potential or adherence properties were apparent. The action of the bile components was different from the action of whole bile. Cholate and deoxycholate produced a decrease in the negativity of zeta potential values of all strains studied whereas taurocholate displayed a shift in zeta potential of hydrophobic strains to more negative values, thus explaining the decrease in the autoaggregation by charge repulsion. However, the decrease in zeta potential caused by cholate and deoxycholate did not increase autoaggregation in a hydrophobic non-adherent strain (CIDCA 531). This suggests that other forces are contributing to autoaggregation.
Influence of selected factors on browning of Camembert cheese
Authors: CARREIRA ALEXANDRA , DILLINGER KLAUS , ELISKASES-LECHNER FRIEDA , LOUREIRO VIRGÍLIO , GINZINGER WOLFGANG , ROHM HARALD
Published: September 2002

Experimental Camembert cheeses were made to investigate the effects on browning of the following factors: inoculation with Yarrowia lipolytica, the use of Penicillium candidum strains with different proteolytic activity, the addition of tyrosine, and the addition of Mn2+, thus leading to 16 different variants of cheese. Two physical colour parameters were used to describe browning, depending on the location in the cheeses: a whiteness index for the outside browning (mould mycelium), and a brownness index for the inside browning (surface of the cheese body). Mn2+ promoted a significant increase of browning at both locations, whereas Yar. lipolytica had the opposite effect. Outside browning was significantly more intense when using the Pen. candidum strain with higher proteolytic activity. A significant interaction was found between Yar. lipolytica and Pen. candidum. The yeast had no effect in combination with a low proteolytic strain of Pen. candidum, but significantly reduced proteolysis and browning in combination with a high proteolytic strain of Pen. candidum. We further confirmed that both strains of Pen. candidum were able to produce brown pigments from tyrosine, and thus both are presumably responsible for the browning activity in this type of cheese.
Immunological effects of yogurt addition to a re-nutrition diet in a malnutrition experimental model
Authors: GAUFFIN CANO PAOLA , AGÜERO GRACIELA , PERDIGÓN GABRIELA
Published: September 2002

The therapeutic and preventive effects of yogurt and lactic acid bacteria on diseases such as cancer, infection and gastrointestinal disorders are well documented. The aim of this research was to study the effects of different doses of yogurt addition after milk re-nutrition diet, on the recovery of the intestinal barrier and mucosal immune function. Experiments were performed on groups of mice, malnourished and re-nourished with milk during 7 d, and mice with diet supplemented with yogurt for 2, 5 and 7 consecutive d. Nutritional parameters such as weight gain, serum total protein, and the number of IgA, IgM and IgG B cells of the small intestine were determined. We also quantified intraepithelial leukocytes, mastocytes and goblet cells, and performed structural and ultrastructural studies on the small intestine. We observed that 5 d of yogurt feeding was the optimal dose for improving gut barrier function and mucosal immune system in a malnutrition model. This effect was not observed with milk re-nutrition. Although the results were better for 5 d of yogurt, addition for 7 d also showed beneficial effects. Yogurt feeding in our model did not impair any gut functions. These results suggest that yogurt addition after a re-nutrition diet gives better recovery of intestinal function than the re-nutrition diet usually recommended. Although these results were obtained in an animal model, they indicate that consumption of yogurt by malnourished children might accelerate the restoration of gut function.
Feeding standards for lactating riverine buffaloes in tropical conditions
Authors: PAUL SHYAM S. , MANDAL ASIT B. , PATHAK NITYA N.
Published: September 2002

Data from 33 feeding trials, conducted on lactating riverine buffaloes from different institutes across India, were subjected to multiple regression analysis to derive nutritional requirements for dry matter (DM), total digestible nutrients (TDN), crude protein (CP) and digestible crude protein (DCP) for maintenance, milk production and body weight gain. Maintenance requirements for DM, TDN, CP and DCP were 59.9, 35.3, 5.43 and 3.14 g/kgW0.75, respectively; corresponding requirements for producing 1 kg 6% FCM were 688, 406, 90.3 and 55.2 g and for 1 g gain in body weight were 3.37, 1.97, 0.327 and 0.23 g. Regression equations had high R2 values (0.61, 0.66, 0.84 and 0.68 for prediction of DM, TDN, CP and DCP, respectively) and the equations (F-value) as well as coefficients were highly significant (P<0.001). Regressed values were used to derive feeding standards. Derived values matched well with the actual intake versus performance of animals under diverse feeding conditions. New standards predicted requirements and intake of nutrients for different production levels better than existing feeding standards. Because they are based on a more thorough analysis of data, the new feeding standards will be appropriate for use widely in India.
Fatty acid composition of ewe milk as affected by solar radiation and high ambient temperature
Authors: SEVI AGOSTINO , ROTUNNO TADDEO , DI CATERINA ROBERTO , MUSCIO ANTONIO
Published: September 2002

Forty lactating Comisana ewes were either exposed to or protected from solar radiation and fed either in the morning or afternoon during summer in a Mediterranean climate. Individual milk samples were taken on days 7, 21 and 42 of the study period to determine fatty acid composition by gas chromatography. Exposure to solar radiation resulted in higher proportions of short-chain and saturated fatty acids in milk, primarily because of increased contents of caproic, capric, lauric, myristic and stearic acids (by 3–18%), and decreased contents of oleic, linoleic and linolenic acids (by 2–9%). As a consequence, the long to short chain and the unsaturated to saturated fatty acid ratios were significantly higher by 4 and 13% respectively in the milk of the protected ewes compared with that of the exposed animals. Provision of shade also led to an increase in the 18[ratio ]0+18[ratio ]1 to 16[ratio ]0 ratio, and to a decrease in the 12[ratio ]0+14[ratio ]0+16[ratio ]0 fatty acid group, which are regarded as reliable indexes of the nutritional property of dietary fat in reducing cholesterol levels in human plasma. Feeding time had little impact on milk fat. Our findings suggest that high ambient temperature may markedly modify the lipid composition of ewe milk and that provision of shade, but not feeding management, can improve the milk fatty acid profile in dairy sheep raised in hot climates.
Microbial composition, including the incidence of pathogens, of goat milk from the Bergamo region of Italy during a lactation year
Authors: FOSCHINO ROBERTO , INVERNIZZI ALESSANDRO , BARUCCO ROBERTO , STRADIOTTO KATIA
Published: September 2002

Sixty samples of raw goat milk intended for Caprino cheese-making were collected from ten farms in the Bergamo area over a 6-month period. Analyses of main microbial groups, somatic cell count (SCC) and pH were performed to determine the effect of origin (farm) and lactation period (April – September) on microbial composition and the incidence of pathogens in milk. Overall mean values were: standard plate count (SPC), 5.0×104 cfu/ml; yeasts, 2.5×102 cfu/ml; coliforms, 9.1×102 cfu/ml; Escherichia coli, 2.9 cells/ml; enterococci, 1.1×102 cfu/ml; lactococci, 3.4×103 cfu/ml; lactobacilli, 3.0×103 cfu/ml; halotolerant bacteria, 8.2×103 cfu/ml; spores of mesophilic aerobic bacteria, 11 cfu/ml; SSC, 9.9×105 cells/ml; pH, 6.63. Moulds and spores of sulphite-reducing clostridia were found intermittently. Neither Salmonella spp. nor Listeria monocytogenes was detected, while Esch. coli O157[ratio ]H7 was isolated from one milk sample (an incidence of 1.7%). Staphylococcus aureus was discovered at a level >102 cfu/ml in 26 samples (43%) with an overall mean of 1.2×103 cfu/ml, whereas coagulase-negative staphylococci were found in 54 samples (90%) with an overall mean of 1.3×103 cfu/ml. Of Staph. aureus strains, 23% proved to be enterotoxinogenic with a prevalence of enterotoxin C producers. Staph. caprae was the coagulase-negative species most frequently isolated; none of the coagulase-negative staphylococci strains synthesized any of the enterotoxins tested for.

Sample source was the major factor affecting the microbial composition of goat milk: significant differences (P<0.01) were observed among samples from different farms for SPC, coliforms, lactococci, lactobacilli and halotolerant bacteria. Period of lactation had a significant effect (P<0.025) on SCC and pH. SPC correlated well with coliforms, lactococci and lactobacilli; SSC did not reveal positive interactions with any microbial groups or pH.
Manothermosonication of heat-resistant lipase and protease from Pseudomonas fluorescens: effect of pH and sonication parameters
Authors: VERCET ANTONIO , BURGOS JUSTINO , LOPEZ-BUESA PASCUAL
Published: September 2002

The effect of different parameters (pH, ultrasonic amplitude and pressure) on the resistance to heat and manothermosonication (MTS) treatments of heat resistant lipase and protease produced by Pseudomonas fluorescens B52 and NCDO 2085, respectively, were studied. Lipase B52 thermoresistance decreases with an increase of pH. However, inactivation by MTS seems to be pH independent. There were only slight increases in the MTS efficiency when increasing pressure at UHT temperatures and the effect of amplitude was different depending on treatment temperature. Protease NCDO 2085, which was very resistant to MTS at 30 °C, was very sensitive to MTS at 76 °C. Increases in applied pressure had no effect on MTS efficiency at 140 °C and its inactivation by MTS was almost temperature independent between 76–109 °C. Data obtained are compared with previous published data and inactivation mechanisms are discussed.
Thermal inactivation of chymosin during cheese manufacture
Authors: HAYES MAURICE G. , OLIVEIRA JORGE C. , McSWEENEY PAUL L. H. , KELLY ALAN L.
Published: September 2002

The aspartic proteinase, chymosin (EC 3.4.23.4) is the principal milk clotting enzyme used in cheese production and is one of the principal proteolytic agents involved in cheese ripening. Varietal differences in chymosin activity, due to factors such as cheese cooking temperature, fundamentally influence cheese characteristics. Furthermore, much chymosin is lost in whey, and further processing of this by-product may require efficient inactivation of this enzyme, with minimal effects on whey proteins. In the first part of this study, the thermal inactivation kinetics of Maxiren 15 (a recombinant chymosin preparation) were studied in skim milk ultrafiltration permeate, whole milk whey and skim milk whey. Inactivation of chymosin in these systems (at pH 6.64) followed first order kinetics with a D45.5 value of 100±21 min and a z-value of 5.9±0.3 °C. D-Values increased linearly with decreasing pH from 6.64 to 6.2, while z-values decreased as pH decreased from 6.64 to 6.4, but were similar at pH 6.4 and 6.2. Subsequent determination of chymosin activity during manufacture of Cheddar and Swiss-type cheese showed good correlations between predicted and experimental values for thermal inactivation of chymosin in whey. However, both types of cheese curd exhibited relatively constant residual chymosin activity throughout manufacture, despite the higher cooking temperature applied in the manufacture of Swiss cheese. Electrophoretic analysis of slurries made from Cheddar and Swiss cheese indicated decreased proteolysis due to chymosin activity during storage of the Swiss cheese slurry, but hydrolysis of sodium caseinate by coagulant extracted from both cheese types indicated similar levels of residual chymosin activity. This may suggest that some form of conformational change other than irreversible thermal denaturation of chymisin takes place in cheese curd during cooking, or that some other physico-chemical difference between Swiss and Cheddar cheese controls the activity of chymosin during ripening.
Effect of monensin sodium on lactational performance of autumn- and spring-calving cows
Authors: MAAS JAMES A. , McCUTCHEON STUART N. , WILSON GAVIN F. , LYNCH GERARD A. , HUNT MURRAY E. , CROMPTON LES A.
Published: September 2002

Monensin sodium is widely used to manipulate ruminal fermentation (Bergen &
Bates, 1984), with the aim of increasing energy supply to the animal. Monensin has
been most widely used in diets of beef cattle and young growing dairy cattle,
particularly in confinement management systems, where the ionophore can be mixed
directly into the ration. Accurate daily dosing of grazing ruminants with small
quantities of rumen modifiers, such as ionophores, proved particularly labour-intensive
and expensive until the development of the controlled-release capsule
(CRC; Laby et al. 1984). Subsequently a commercially available CRC containing
monensin sodium was developed (Elanco Animal Health, Cambridge, NZ) facilitating
its use in grazing animals. It has also been tested as a method of reducing the
incidence of bloat in lactating dairy cows grazing pastures containing legumes.
Effect of intramammary infection by Staphylococcus caprae on somatic cell counts and milk composition in goats
Authors: SÁNCHEZ ANTONIO , FERNÁNDEZ CARLOS , CONTRERAS ANTONIO , LUENGO CARLOS , RUBERT JOAQUÍN
Published: September 2002

Since its identification by Devirese et al. (1983), Staphylococcus caprae has been
frequently isolated from udder halves of goats with subclinical intramammary
infection (IMI) (Contreras et al. 1995; Poutrel et al. 1996). Several different studies
have demonstrated the capacity of Staph. caprae to persist throughout lactation
(Poutrel et al. 1996; Contreras et al. 1997; Bedidi-Madani et al. 1998a) and during the
dry period (Poutrel, 1984). Bedidi-Madani et al. (1998a) found that isolates of Staph.
caprae from udders of uninfected goats express potential virulence factors (different
exoproteins and slime); other researchers have occasionally isolated it from clinical
cases of goat mastitis (Deinhofer & Pernthaner, 1995), or from human clinical
specimens associated with bone and joint infection (Vandenesh et al. 1995;
Shuttleworth et al. 1997). In spite of these forms of pathogenicity, some studies have
not shown significant increases in somatic cell count (SCC) of milk from goat udder
halves infected by Staph. caprae (Deinhofer & Pernthaner, 1995; Poutrel et al. 1996).
Moreover, there is a lack of information on the effect of infection by this mammary
pathogen on milk yield and composition. Knowledge of repercussions for hygiene and
production would be useful in mastitis control programmes in view of the high
frequency of isolation (higher than 22% of the staphylococci isolated) of Staph.
caprae in dairy goat herds (Contreras et al. 1995; Poutrel et al. 1996). The aim of the
present investigation was to ascertain the significance of persistent subclinical IMI
by Staph. caprae on SCC, milk yield and physical-chemical parameters of Murciano-Granadina
goat milk at mid-lactation.
Expression of urokinase plasminogen activator receptor in resting and activated bovine neutrophils
Authors: POLITIS IOANNIS , ZAVIZION BORIS , CHELI FEDERICA , BALDI ANTONELLA
Published: September 2002

Changes in urokinase-plasminogen activator (u-PA) and u-PA receptor (u-PAR) expression at the protein and mRNA level in resting neutrophils and in neutrophils activated by phorbol myristate acetate (PMA) were examined. Low amounts of u-PA were found intracellularly or membrane-bound in resting neutrophils. However, incubation of resting neutrophils with purified exogenous u-PA (10 IU/ml) revealed extensive binding of u-PA to cell membranes. Excess amino-terminal fragment of the u-PA molecule, a proteolytically inactive fragment of u-PA (amino acids 1–135) blocked binding of exogenous u-PA to the cell membrane. These results, collectively, indicate that the binding of u-PA is specific and that resting neutrophils have unoccupied u-PA receptors on their cell membrane. Addition of PMA led to an increase (P<0.01) in total cell-associated, membrane-bound u-PA activity and u-PA mRNA expression by bovine neutrophils. In contrast, PMA increased u-PAR mRNA levels but this was accompanied by a decrease (2.5-fold; P<0.01) in free, unoccupied u-PA binding sites. No significant effects on total cell-associated or membrane-bound u-PA were found when neutrophils were treated with 4-phorbol 12,13 didecanoate, a phorbol ester that does not activate protein kinase C (PKC). Furthermore, addition of 1-(5-isoquinolinesylphonyl)-2-methylpiperazine dihydrochloride (H-7), a potent PKC inhibitor, blocked the effect of PMA on total cell-associated u-PA activity. Thus, PKC plays a role in the modulation of u-PA and u-PAR by PMA in bovine neutrophils.
Lactobacillus reuteri DSM 20016: purification and characterization of a cystathionine γ-lyase and use as adjunct starter in cheesemaking
Authors: DE ANGELIS MARIA , CURTIN ÁINE C. , McSWEENEY PAUL L. H. , FACCIA MICHELE , GOBBETTI MARCO
Published: September 2002

A homo-tetrameric ∼160-kDa cystathionine γ-lyase was purified to homogeneity from Lactobacillus reuteri DSM 20016 by four chromatographic steps. The activity was pyridoxal-5′-phosphate dependent and the enzyme catalyzed the α,γ-elimination reaction of L-cystathionine, producing L-cysteine, ammonia and α-ketobutyrate. The enzyme was active towards a range of amino acids and amino acid derivatives, including methionine. The pH and temperature optima were found to be 8.0 and 35 °C, respectively. Isoelectric pH (pI) was ∼5.0 as determined by two-dimensional electrophoresis. Sensitivity to chemical inhibitors was typical of lactococcal cystathionine γ- and β-lyases, except it was inhibited by sulphydryl reagents. The N-terminal sequence was MKFNTQLIHGGNSED, which had 100% homology with cystathionine β-lyase of Lb. reuteri 104R (Accession Number CAC05298). Lb. reuteri DSM 20016, together with 10 other strains of non-starter lactic acid bacteria, was used as adjunct starter in the production of miniature Canestrato Pugliese-like cheeses. After 40 d ripening, the water-soluble extract of the cheeses with added Lactobacillus fermentum DT41 and Lb. reuteri DSM 20016 contained the highest enzyme activities on cystathionine and methionine substrates. Determinations of methanethiol, dimethyl sulphide, dimethyl disulphide and dimethyl trisulphide in the miniature cheeses confirmed the findings of enzyme activities.
Native Lords and the Church in Thirteenth-Century Strathearn, Scotland
Authors: NEVILLE CYNTHIA J.
Published: September 2002

The thirteenth century in Scotland witnessed a determined effort on the part of the crown and its ecclesiastical officials to initiate a series of reforms comparable to those that had so deeply altered the social and religious life of England and continental Europe. An important aspect of the transformation that occurred in Scotland was the consolidation of a network of parish churches throughout the kingdom. Scottish authorities, however, encountered several obstacles in their attempts to create parishes, and especially to assign sufficient revenues to them. In the lordships controlled by old Celtic families in particular the Church's designs sometimes clashed with the interests of great native land-holders and their kinsmen. In many of these lordships the process of parish formation was ultimately the result of negotiation and litigation which saw the Church forced to accommodate the claims of Celtic landowners. This article examines, in the context of the native lordship of Strathearn, the struggles that marked the creation and consolidation of some parishes in thirteenth-century Scotland.
The Office for King Charles the Martyr in the Book of Common
Prayer, 1662–1685
Authors: LACEY ANDREW
Published: September 2002

This article investigates the development of the use of texts and images in commemorating the
regicide of Charles I , from private commemoration among Royalists during the Republic, to its
official institution after the Restoration. The article will argue that the Office gave official sanction
to an image of the virtuous suffering king which had been in existence even before his execution. The
Office also presented a particular view of the king's moral character, the causes of the Civil War
and the Restoration which was to become the accepted account expounded in commemorative sermons
for the next 150 years. Drawing on Old Testament themes, the Office also aimed to point a political
moral used by successive governments, namely that attacks on the established order incurred divine
punishment.
Gregory the Great's ‘Political Thought’
Authors: HIPSHON DAVID
Published: September 2002

Gregorian scholars have been unable to reconcile widely differing views on Gregory the Great's ‘political thought’. The trend has been to view him as either ambivalent towards secular authority or completely indifferent to it. This article aims to demonstrate that Gregory the Great's conception of an ordered and hierarchic universe not only encompassed both secular and ecclesiastical spheres but also allowed each a positive role in the work of salvation. His ideas, influenced by neo-Platonic thought, differed substantially from those of St Augustine and were vital to the development of an early medieval partnership between secular and ecclesiastical authority.