Acid Orcein-Iron and Acid Orcein-Copper Stains for Elastin

Paraffin sections of formol-fixed tissues stained 4-18 hr in 70% alcohol containing 1% orcein and 1% of concentrated (12 N) HCl by volume yield the familiar purple brown elastin and red nuclei on a pink background. When sections so stained are transferred directly from the stain to 70% alcohol containing 0.02% ferric chloride (FeCl₃·6 H₂O) or 0.02% copper sulfate (CuSO₄·5 H₂O) for a 15 sec to 3 min period, elastin coloration is changed to black or reddish black and chromatin staining to reddish black. The procedure can be counterstained with picro-methyl blue to yield blue collagen and reticulum or with our flavianic acid, ferric chloride, acid fuchsin mixture to give deep yellow background and deep red collagen.     

Fitness of wild‐caught Drosophila melanogaster females: allozyme variants of GPDH, ADH, PGM, and EST

We have collected several hundred Drosophila melanogaster flies (near Davis, California), isolated them individually, without anesthesia, at the collecting site, and estimated the fitness components of the wild‐caught females under different environmental conditions. The fitness parameters measured are fecundity, oviposition rate, and productivity (egg‐to‐adult viability, development rate, and number of progeny). The environmental variables are two temperatures (22°C and 28°C) and two densities (‘scant’ and ‘crowded’). After the fitness measurements are completed for each individual female, its genotype is determined at four loci encoding enzymes: GPDH and ADH, located on chromosome II and PGM and EST‐C, located on chromosome III. Density has a large significant effect on productivity; temperature has significant effects on fecundity, oviposition rate, and development rate. The experiments show that allozyme polymorphisms are associated with selection effects. Fitness differences between allozyme genotypes occur for all fitness components, except oviposition rate. But which genotype is superior depends on the environmental conditions; heterozygotes exhibit higher fitness than homozygotes in a number of cases, but inferior in others. A unique feature of the present experiments is that the experimental flies are wild‐caught females rather than laboratory‐bred individuals. This revised version was published online in July 2006 with corrections to the Cover Date.     

Chemical Analysis of the Lamella Walls of Agaricus bisporus Fruit Bodies

Purified lamella wall fragments of Agaricus bisporus fruit bodies were analyzed and shown to consist of neutral sugars (46.5%), hexosamines (31.7%), proteins (9.5%), some lipid material (10.0%), and ash (1.4%). The cell walls were fractionated on the basis of their polysaccharide solubility in water and alkaline solutions. The isolated fractions, using methylation analysis, exhibited striking chemical structural differences compared with the same fractions obtained from the corresponding vegetative cells and fruit bodies (stipe and pileus) walls. The structural differences detected in the wall seem to correspond to the ultimate differentiation of the mycelium inside the fruit body of A. bisporus. Received: 30 November 1998 / Accepted: 29 January 1999     

Parathyroid Glands of Amphibians. II. Structural and Biochemical Changes in Amphibian Tissues Elicited by Parathyroid Hormone Under Varying Conditions of Season and Temperature

The parathyroid glands have received relatively little attentionwith regard to their impact on the internal milieu in amphibians.Present information, however, clearly indicates that distributionof mineral in frog tissues and body fluids is under hormonalregulation; further modifications are imposed by season andtemperature. Under conditions of cold acclimation or duringwinter normal amphibian bone shows minimal rates of carbohydrateutilization: simultaneously, phosphate is conserved by reducedexcretion and increased incorporation in tissue. Exogenous parathyroidhormone, injected under these conditions when endogenous titersmay be low due to glandular degeneration, reverses these effects,and phosphate is lost in a hyperphosphaturic urine. During summeror periods of warm acclimation, hormone promotes incorporationof phosphate in tissues, and increases rates of carbohydratemetabolism in bone; citric acid, which may act in solubilizingbone mineral, is elevated in the bone. Concurrently, pre-existingsulfated mucopolysaccharides of "old" bone may be degraded,while epiphyseal zones enlarge and may exhibit accelerated orabnormal elaboration of sulfated components of cartilage and/orosteoid matrix.     

Bioapatite to calcite,an unusual transformation seen in fossil bones affected by aquatic bioerosion

A characteristic aquatic bioerosion, which peripherally penetrates the bone cortex, has previously been described from the 7‐million‐year‐old Cerro de la Garita calcareous lakeshore site (Concud, Teruel, Spain). This site has also yielded body fossils that appear to have been partly or entirely replaced by a delicate, white ‘crumbly substance’ that disaggregates upon touch. High‐resolution image and chemical analyses of the ‘crumbly substance’, bioeroded and non‐altered fossils, fresh bones and the site sediment are here described. The ‘crumbly substance’ was identified as calcite formed by non‐cemented micro‐crystals, preserving identical micro‐tunnelling than was observed in bioeroded fossil bones. This paper reports these results in detail and discusses how the original bone bioapatite may have been transformed. Results of these analyses have led us to propose that micro‐organisms, peripherally boring the bone, could also have influenced the transformation of bone bioapatite to calcite under specific micro‐environmental conditions.     

Encapsulation of soybean meal with fats enriched in palmitic and stearic acids: effects on rumen-undegraded protein and in vitro intestinal digestibility

Fat coating of soybean meal (SBM) can reduce its protein degradability in the rumen, but the encapsulation of SBM with palmitic (PA) and stearic acids (SA) has not yet been investigated, despite both fatty acids are common energy sources in dairy cow diets. This study aimed to evaluate the effects of applying a novel method, using either 400 or 500 g fat/kg (treatments FL40 and FL50, respectively), which was enriched in PA and SA at different ratios (100:0, 75:25, 50:50, 25:75 and 0:100), on physical and chemical characteristics, ruminal degradability, solubility and in vitro intestinal protein digestibility (IVIPD) of the obtained products. Encapsulation of SBM in fat resulted in greater mean particle size and lower bulk density and protein solubility than unprotected SBM (USBM). Treatment FL50 resulted in increased (p < 0.01) rumen-undegraded protein (RUP) compared to USBM. There were no differences in RUP of SBM when different PA: SA ratios were used. The mean RUP content of treatments FL40 and FL50 (306 and 349 g/kg, respectively) was greater compared to USBM (262 g/kg, p < 0.05), but lower than that for a standard heat-treated SBM (431 g/kg). Values of IVIPD did not differ among SBM, heat-treated SBM and FL40 and FL50 samples, all being greater than 97.8%. In conclusion, encapsulation of SBM with fats enriched in PA and SA proved to be effective in reducing protein solubility and increasing RUP without depressing protein digestibility in the intestine. For validation of the method, in vivo research to investigate the effects of these products on the production of dairy cows is warranted.     

Incidence of numerical chromosome aberrations in meningioma tumors as revealed by fluorescence in situ hybridization using 10 chromosome-specific probes

OBJECTIVE: Although information on the cytogenetic characteristics of meningioma tumors has accumulated progressively over the past few decades, information on the genetic heterogeneity of meningiomas is still scanty. The aim of the present study was to analyze by interphase fluorescence in situ hybridization (FISH) the incidence of numerical abnormalities for chromosomes 1, 9, 10, 11, 14, 15, 17, 22, X, and Y in a group of 70 consecutive meningioma tumors. Another goal was to establish the potential associations among the altered chromosomes, as a way to assess both intertumoral and intratumoral heterogeneity. METHODS: For the purpose of the study, 70 patients diagnosed with meningioma were analyzed. Interphase FISH for the detection of numerical abnormalities for chromosomes 1, 9, 10, 11, 14, 15, 17, 22, X, and Y was applied to fresh tumor samples from each of the patients studied. RESULTS: The overall incidence of numerical abnormalities was 76%. Chromosome Y in males and chromosome 22 in the whole series were the most common abnormalities (46% and 61%, respectively). Despite the finding that monosomy of chromosome 22/22q(-) deletions are the most frequent individual abnormality (53%), we have observed that chromosome gains are significantly more common than chromosome losses (60% versus 40%). Chromosome gains corresponded to abnormalities of chromosomes 1 (27%), 9 (25%), 10 (23%), 11 (22%), 14 (33%), 15 (22%), 17 (23%), and X in females (35%) and males (23%) whereas chromosome losses apart from chromosome 22 frequently involved chromosomes 14 (19%), X in males (23%), and Y in males (32%). Although an association was found among most gained chromosomes on one side and chromosome losses on the other side, different association patterns were observed. Furthermore, in the latter group, monosomy 22/22q(-) was associated with monosomy X in females and monosomy 14/14q(-) was associated with nulisomy Y in males. In addition, chromosome losses usually involved a large proportion of the tumor cells whereas chromosome gains were restricted to small tumor cell clones, including tetraploid cells. CONCLUSIONS: Our results show that meningiomas are genetically heterogeneous tumors that display different patterns of numerical chromosome changes, as assessed by interphase FISH.     

Arabidopsis Uracil DNA Glycosylase (UNG) Is Required for Base Excision Repair of Uracil and Increases Plant Sensitivity to 5-Fluorouracil

Uracil in DNA arises by misincorporation of dUMP during replication and by hydrolytic deamination of cytosine. This common lesion is actively removed through a base excision repair (BER) pathway initiated by a uracil DNA glycosylase (UDG) activity that excises the damage as a free base. UDGs are classified into different families differentially distributed across eubacteria, archaea, yeast, and animals, but remain to be unambiguously identified in plants. We report here the molecular characterization of AtUNG (Arabidopsis thaliana uracil DNA glycosylase), a plant member of the Family-1 of UDGs typified by Escherichia coli Ung. AtUNG exhibits the narrow substrate specificity and single-stranded DNA preference that are characteristic of Ung homologues. Cell extracts from atung^−/− mutants are devoid of UDG activity, and lack the capacity to initiate BER on uracil residues. AtUNG-deficient plants do not display any apparent phenotype, but show increased resistance to 5-fluorouracil (5-FU), a cytostatic drug that favors dUMP misincorporation into DNA. The resistance of atung^−/− mutants to 5-FU is accompanied by the accumulation of uracil residues in DNA. These results suggest that AtUNG excises uracil in vivo but generates toxic AP sites when processing abundant U:A pairs in dTTP-depleted cells. Altogether, our findings point to AtUNG as the major UDG activity in Arabidopsis.