Prostaglandin (PG) accumulation by mouse ovaries, oviducts, and uteri

Uteri, ovaries and oviducts from mice were collected at autopsy. Tissue slices were incubated with [³H]-PGE₂ in the presence or absence of a large excess (100 fold) of nonradioactive PGE₂ using 0.01M sodium phosphate buffer (pH 7.2). Bound and free PGs were separated by a filtration technique. PGE₂ accumulation by the uteri was evaluated as a function of incubation time, wet weight of tissues, and reproductive state. The tissue to medium ratio (T/M) was greater than 1.0 for uteri as the time of incubation increased. This suggests the presence of PGE₂ binding sites in mouse uterine tissue. Also, PGE₂ accumulation was not observed in oviducts or in ovaries.     

Inhibition of peroxidase, trypsin, and alpha-chymotrypsin by platinum (II) and platinum (IV) complexes

Effects of various complexes of platinum (II) and platinum (IV) on activities of trypsin, alpha-chymotrypsin, and peroxidase were compared. The platinum (II) complexes were found to inhibit these enzymes, though with variable efficiency. The platinum (IV) complexes at concentrations < or = 0.2 mM efficiently inhibited peroxidase but had no effect on the proteases. An enzymatic assay was developed to measure the most effective peroxidase inhibitor (cisplatin) at concentrations of 5-50 microM in the presence of fivefold excess of its isomer (transplatin).     

Adsorption of several actinide (Th,U) and lanthanide (La,Eu, Yb) ions by Mycobacterium smegmatis

Adsorption measurements of several actinide [thorium (Th), uranium (U)] and lanthanide [lanthanum (La), europium (Eu), ytterbium (Yb)] cations by Mycobacterium smegmatis showed that sorption kinetics followed a three-phase pattern. For 5% (w/w) bacterial suspensions at pH 1, maximum cation biosorption per gram dry biomass corresponded to 170 mol Th⁴⁺ and 187 mol UO _inf2 ^sup2+ . Adsorption of all cations studied obeyed the Brunauer-Emmett-Teller isotherm, which assumes multilayer binding at constant energy. Plots for the Scatchard model showed the existence of at least two types of cation complexation site, with strong and weak affinity and negative cooperation. Th⁴⁺ was preferentially adsorbed with respect to the other cations, although all species appeared to compete for the same sites independently of bacterial viability. Adsorption of these cations was accompanied by partial release of magnesium from the cell wall, indicating that exchange reactions occurred at magnesium (Mg)-bonding sites.     

Synthesis, characterization, X-ray structure and DNA photocleavage by cis-dichloro bis(diimine) Co(III) complexes

Complexes of the type [Co(LL)2Cl2]Cl, where LL = N,N'-ethylenediamine (en), 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen), 1,10-phenanthroline-5,6-dione (phendione) and dipyrido[3,2-a:2',3'-c]phenazine (dppz) have been synthesized and characterized by elemental analyses, IR, UV-visible and NMR spectroscopy. Crystal structure of [Co(phendione)2Cl2]Cl x 0.5 HCl x 3.5 H2O has been solved and refined to R = 0.0552. The crystal is monoclinic with space group C2/c; a = 25.730(2) A, b = 12.375(1) A, c = 18.979(2) A, beta = 119.925(1) degrees and Z = 8. The DNA binding characteristics of the complexes, investigated by covalent binding assay, viscosity measurements and competitive binding fluorescence measurements show that the complexes interact with DNA covalently except the complex containing the planar dppz ligand which intercalates within the base pairs of DNA. The complexes containing en, phen and phendione cleave plasmid pBR 322 DNA upon irradiation under aerobic conditions while the complex containing the dppz ligand cleaves DNA upon irradiation under inert atmosphere. Molecular modeling studies show that the minimized structure of [Co(phendione)2Cl2]+, maintained the octahedral structure while binding to the N7 of guanines and the ligand fits into the major groove without disrupting the helical structure of the B-DNA.     

Prostaglandin (PG) accumulation in vitro by mouse ovaries, oviducts, and uteri

Uteri, ovaries and oviducts from mice were collected at autopsy. Tissue slices were incubated with [3H]-PGE2 in the presence or absence of a large excess (100 fold) of nonradioactive PGE2 using 0.01M sodium phosphate buffer (pH 7.2). Bound and free PGs were separated by a filtration technique. PGE2 accumulation by the uteri was evaluated as a function of incubation time, wet weight of tissues, and reproductive state. The tissue to medium ratio (T/M) was greater than 1.0 for uteri as the time of incubation increased. This suggests the presence of PGE2 binding sites in mouse uterine tissue. Also, PGE2 accumulation was not observed in oviducts or in ovaries.     

Mitochondrial permeability transition mediates apoptosis induced by N-methyl(R)salsolinol,an endogenous neurotoxin,and is inhibited by Bcl-2 and rasagiline,N-propargyl-1(R)-aminoindan

The role of mitochondrial permeability transition (PT) in apoptosis induced by an endogenous neurotoxin, N-methyl(R)salsolinol [NM(R)Sal], was studied by use of dopaminergic neuroblastoma SH-SY5Y cells. NM(R)Sal reduced mitochondrial membrane potential, DeltaPsim, in the early phase of apoptosis, which was not suppressed by a pan-caspase inhibitor, but was antagonized by Bcl-2 and cyclosporin A, suggesting the involvement of the PT in NM(R)Sal-induced loss of DeltaPsim. NM(R)Sal-induced apoptosis was completely inhibited not only by Bcl-2 and a pan-caspase inhibitor, but also by cyclosporin A, suggesting the essential role of the PT in NM(R)Sal-induced apoptosis. In mitochondria isolated from rat liver, NM(R)Sal induced swelling and reduced DeltaPsim, which was inhibited by cyclosporin A and Bcl-2 overexpression. These results indicate that NM(R)Sal induced the PT by direct action on the mitochondria. Rasagiline, N-propargyl-1(R)-aminoindan, which is a now under a clinical trial for Parkinson's disease, suppressed the DeltaPsim reduction, release of cytochrome c, and apoptosis induced by NM(R)Sal in SH-SY5Y cells. Rasagiline also inhibited the NM(R)Sal-induced loss of DeltaPsim and swelling in the isolated mitochondria, proving that rasagiline directly targets the mitochondria also. Altogether, mitochondrial PT plays a key role both in NM(R)Sal-induced cell death and the neuroprotective effect of rasagiline.     

Age and growth of the Black Sea turbot, Psetta maxima (Linneaus, 1758) (Pisces: Scophthalmidae), estimated by reading otoliths and by back-calculation

Age and growth of the Black Sea turbot, Psetta maxima, were determined from a total of 1445 individuals collected along the eastern Black Sea coast between 1990 and 1996. Age was estimated by interpreting growth rings in whole and broken sagittal otoliths. The former method underestimated the age over 5 years, and a maximum age of 11 years was observed by the latter. Marginal increment analysis clearly showed that a single annulus is formed in early summer each year. Growth in length differed between sexes, and females attained a larger size than males at the same age. No significant difference was found between the mean observed total length (TL), the back‐calculated TL derived from radius measurements and the TL estimated from otolith size–fish size relationship. The von Bertalanffy growth parameters estimated by the length‐at‐age data were: L_∞ = 96.24 cm; K = 0.119 year^?1; t₀ = ?0.01 year for the entire population.     

Diet and food selection by Ramnogaster arcuata (Osteichthyes, Clupeidae)

The goals of this study were to describe the diet and estimate the trophic level and food selection of Jenyns's sprat Ramnogaster arcuata, one of the common fishes in the Bahía Blanca estuary in Argentina. The copepods Acartia tonsa [53·7% index of relative importance (I(RI))] and Eurytemora americana (13·4% I(RI)), the mysid Arthromysis magellanica (13·9%I(RI)) and the small shrimp Peisos petrunkevitchi (8·2% I(RI)) were the most important food items for this species, and its diet exhibited monthly variability with respect to the principal prey categories. The zooplankton species in the study area consisted of 32 taxa. Acartia tonsa was the most abundant species [54% individuals (N) m(-3)], followed by Balanus glandula (13·8% N m(-3)) and E. americana (10·1% N m(-3)). The rest of the zooplankton groups represented <3% N m(-3). The most preferred items throughout the year were A. magellanica and Idotea sp. The trophic level value estimated was 3·1.     

Sustained muscle contraction induced by agonists, growth factors, and Ca(2+) mediated by distinct PKC isozymes

The role of protein kinase C (PKC) in sustained contraction was examined in intestinal circular and longitudinal muscle cells. Initial contraction induced by agonists (CCK-8 and neuromedin C) was abolished by 1) inhibitors of Ca(2+) mobilization (neomycin and dimethyleicosadienoic acid), 2) calmidazolium, and 3) myosin light chain (MLC) kinase (MLCK) inhibitor KT-5926. In contrast, sustained contraction was not affected by these inhibitors but was abolished by 1) the PKC inhibitors chelerythrine and calphostin C, 2) PKC-epsilon antibody, and 3) a pseudosubstrate PKC-epsilon inhibitor. GDPbetaS abolished both initial and sustained contraction, whereas a Galpha(q/11) antibody inhibited only initial contraction, implying that sustained contraction was dependent on activation of a distinct G protein. Sustained contraction induced by epidermal growth factor was inhibited by calphostin C, PKC-alpha,beta,gamma antibody, and a pseudosubstrate PKC-alpha inhibitor. Ca(2+) (0.4 microM) induced an initial contraction in permeabilized muscle cells that was blocked by calmodulin and MLCK inhibitors and a sustained contraction that was blocked by calphostin C and a PKC-alpha,beta,gamma antibody. Thus initial contraction induced by Ca(2+), agonists, and growth factors is mediated by MLCK, whereas sustained contraction is mediated by specific Ca(2+)-dependent and -independent PKC isozymes. G protein-coupled receptors are linked to PKC activation via distinct G proteins.     

Production of beauvericin,moniliformin, fusaproliferin,and fumonisins b(1), b(2), and b(3) by fifteen ex-type strains of fusarium species

Fifteen Fusarium species were analyzed by high-performance liquid chromatography for the production of six mycotoxins in corn grits cultures. Production of mycotoxins ranged from 66 to 2,500 micro g/kg for fumonisin B(1), 0.6 to 1,500 micro g/g for moniliformin, 2.2 to 720 micro g/g for beauvericin, and 12 to 130 micro g/g for fusaproliferin. Fumonisin B(2) (360 micro g/kg) was produced by two species, fumonisin B(3) was not detected in any of the 15 species examined, and Fusarium bulbicola produced none of the six mycotoxins that we analyzed.     

Threats to observers,keepers, visitors,and others by zoo mangabeys (Cercocebus galeritus chrysogaster)

The facial threats of ten captive golden-bellied mangabeys (Cercocebus galeritus chrysogaster) were categorized by object threatened. Adult males threatened more than did females except when the object was a nonhuman primate in a neighboring cage. Juvenile mangabeys threatened mainly in play within their own enclosures. Keepers and observers did not differ in frequency of being threatened by the mangabeys. Adult female mangabeys seemed more concerned with neighboring cages of nonhuman primates than were the juveniles and the males. Human visitors to the enclosures received by far the most threats of any targets, certainly far more than the observers and keepers. They were treated like interlopers. Keepers were treated like familiar conspecifics, observers like familiar neighbors. The implications of these findings for captive management of primates and for observational methods in behavioral primatology are discussed.     

Gamete discharge by Bryopsis plumosa (Codiales, Chlorophyta) induced by blue and UV-A light

Gamete discharge by the coenocytic green alga Bryopsis plumosa (Hudson) C. Agardh is induced by light. The mature male gametangia consist of a mass of quiescent male gametes and a large central vacuole. Within a few minutes after the onset of irradiation, breakdown of the tonoplast of the central vacuole and initiation of gamete motility occur simultaneously. This is followed by a forced discharge of moving gametes through a hole ruptured at the subapical region of the gametangium. The action spectrum for the light-induced gamete discharge was determined from a series of fluence-response curves. This action spectrum, having two major maxima at 370 and 450 nm, indicates the involvement of a blue light/UV-A-absorbing photoreceptor previously described as ‘cryptochrome’.     

Cadmium, Zinc, Copper, Silver and Chromium(III) removal from wastewaters by Sphaerotilus natans

Living cells of Sphaerotilus natans are used for heavy metal's (Cd, Zn, Cu, Ag, and Cr) removal from aqueous solutions simulating the polluting power of acid industrial wastewaters. At low metal concentrations (<25?mg/l) this microorganism is able to remove within 8–15 days Cd, Zn, Cu, and Ag with excellent yields (from 81 to 99%) often increasing with starting metal concentration. The yield observed for Cr(III) removal, never exceeding 60%, is not appreciably influenced by the starting biomass level; in addition, the time necessary to reach the equilibrium concentration is always remarkably longer (>30 days) than for the other metals. At much higher concentrations, the removal of all the metals is strongly affected in terms of both yield reduction and increase in the time necessary to reach the equilibrium concentrations. Under the hypothesis of mass transfer limitation, the kinetic study of batch runs suggests that metal diffusion from the bulk to the surface of S. natans clumps could be responsible not only for the simple biosorption of the tested metallic micronutrients or abiotic metals, but even for the cell penetration by ions of biological significance, like Mg²⁺ and Fe³⁺.     

DNA oxidatively damaged by chromium(III) and H(2)O(2) is protected by the antioxidants melatonin, N(1)-acetyl-N(2)-formyl-5-methoxykynuramine, resveratrol and uric acid

Chromium (Cr) compounds are widely used industrial chemicals and well known carcinogens. Cr(III) was earlier found to induce oxidative damage as documented by examining the levels of 8-hydroxydeoxyguanosine (8-OH-dG), an index for DNA damage, in isolated calf thymus DNA incubated with CrCl(3) and H(2)O(2). In the present in vitro study, we compared the ability of the free radical scavengers melatonin, N(1)-acetyl-N(2)-formyl-5-methoxykynuramine (AFMK), resveratrol and uric acid to reduce DNA damage induced by Cr(III). Each of these scavengers markedly reduced the DNA damage in a concentration-dependent manner. The concentrations that reduced 8-OH-dG formation by 50% (IC(50)) were 0.10 microM for both resveratrol and melatonin, and 0.27 microM for AFMK. However, the efficacy of the fourth endogenous antioxidant, i.e. uric acid, in terms of its inhibition of DNA damage in the same in vitro system was about 60--150 times less effective than the other scavengers; the IC(50) for uric acid was 15.24 microM. These findings suggest that three of the four antioxidants tested in these studies may have utility in protecting against the environmental pollutant Cr and that the protective effects of these free radical scavengers against Cr(III)-induced carcinogenesis may relate to their direct hydroxyl radical scavenging ability. In the present study, the formation of 8-OH-dG was likely due to a Cr(III)-mediated Fenton-type reaction that generates hydroxyl radicals, which in turn damage DNA. Once formed, 8-OH-dG can mutate eventually leading to cancer; thus the implication is that these antioxidants may reduce the incidence of Cr-related cancers.     

Disparate cleavage of poly-(ADP-ribose)-polymerase (PARP) and a synthetic tetrapeptide, DEVD, by apoptotic cells

In the present investigations, we have shown differential cleavage of cellular PARP and a caspase 3-selective synthetic tetrapeptide substrate, Z-DEVD-AFC or Ac-DEVD-AMC using a T lymphoblastoid cell line Jurkat, and its variant clone E6.1(J-E6). Anti-Fas antibody-mediated apoptosis resulted in DNA fragmentation and PARP cleavage in both Jurkat and J-E6 cells. However, unlike Jurkat, J-E6 cells did not cleave a synthetic tetrapeptide substrate efficiently. The failure to cleave the DEVD tetrapeptide by apoptotic J-E6 cells was not due to insufficient expression or processing of caspase 3 in J-E6 cells. Interestingly, when the J-E6 cells were transiently transfected with a cDNA encoding caspase 3, efficient cleavage of Z-DEVD-AFC was achieved. The observations that apoptotic J-E6 cells barely cleaved a synthetic DEVD tetrapeptide, but efficiently cleaved endogenous PARP, potentially at the most preferred DEVD site, suggest that active caspases may have disparate characteristics to recognize substrates presented in different context.     

Energy efficiency of acetone,butanol, and ethanol (ABE) recovery by heat-integrated distillation

Bioprocess and Biosystems Engineering - Acetone, butanol, and ethanol (ABE) is an alternative biofuel. However, the energy requirement of ABE recovery by distillation is considered elevated...     

Behavioral, Ecological, and Evolutionary Aspects of Meat-Eating by Sumatran Orangutans (Pongo abelii)

Meat-eating is an important aspect of human evolution, but how meat became a substantial component of the human diet is still poorly understood. Meat-eating in our closest relatives, the great apes, may provide insight into the emergence of this trait, but most existing data are for chimpanzees. We report 3 rare cases of meat-eating of slow lorises, Nycticebus coucang, by 1 Sumatran orangutan mother–infant dyad in Ketambe, Indonesia, to examine how orangutans find slow lorises and share meat. We combine these 3 cases with 2 previous ones to test the hypothesis that slow loris captures by orangutans are seasonal and dependent on fruit availability. We also provide the first (to our knowledge) quantitative data and high-definition video recordings of meat chewing rates by great apes, which we use to estimate the minimum time necessary for a female Australopithecus africanus to reach its daily energy requirements when feeding partially on raw meat. Captures seemed to be opportunistic but orangutans may have used olfactory cues to detect the prey. The mother often rejected meat sharing requests and only the infant initiated meat sharing. Slow loris captures occurred only during low ripe fruit availability, suggesting that meat may represent a filler fallback food for orangutans. Orangutans ate meat more than twice as slowly as chimpanzees (Pan troglodytes), suggesting that group living may function as a meat intake accelerator in hominoids. Using orangutan data as a model, time spent chewing per day would not require an excessive amount of time for our social ancestors (australopithecines and hominids), as long as meat represented no more than a quarter of their diet.     

Growth light level and photon absorption by cells of Chlamydomonas rheinhardii,Dunaliella tertiolecta (Chlorophyceae,Volvocales), Scenedesmus obliquus (Chlorophyceae,Chlorococcales) and Euglena viridis (Euglenophyceae,Euglenales)

Reductions in the growth light level (40 to 6 μmol m^-2 s^-1) resulted in increases in chlorophyll and protein per cell for all of the species examined. Only Dunaliella tertiolecta exhibited a reduction in chlorophyll a:b ratio with decreases in the photon flux density. However, the specific absorption coefficient (ā? _i ) normalized to chlorphyll a (ā? _a remained invariant for all of the microalgae studied. Constant values for the specific absorption coefficient normalized to the total pigment content (ā? _a+b ) were also found for the species Chlamydomonas rheinhardii, Euglena viridis and Scenedesmus obliquus. In contrast ā? _a+b for D. tertiolecta decreased with a reduction in light level due to an increase in the proportion of chlorophyll b. Differences in ā? _i were related to cell size and pigment content and possible reasons for the constancy of ā? _a discussed. Increases in the absorption cross sections (¯sQ _a ) were also found at reduced light levels due to an increase in the absorptance per cell (α_cell). The lower α_cell for D. tertiolecta, compared with C. rheinhardii was exactly compensated for by a larger light-capturing area. Although the increase in α_cell does not compensate for the reduction in the incident light level, it does reduce this range by half on an absorbed light basis.     

Visual discriminations of spokes, sectors, and circles by the honeybee (Apis mellifera)

A new cue for visual discrimination by the honeybee has been demonstrated. Bees detected the position of the centre of symmetry of radial patterns of spokes, sectors, and circles relative to their point of choice in the learning process, irrespective of the pattern. When trained with one of these patterns versus a blank target, the bees discriminated a shift in the position of the centre of symmetry by as little as 5 degrees , in some cases with unfamiliar test patterns. A pattern of spokes or rings also stabilized the vision of the bees in the horizontal plane so that the position of a plain black area could then be discriminated. In other experiments, bees discriminated half of a pattern of radial spokes or concentric circles from the other half, cut either vertically or horizontally, and irrespective of scale. Therefore these patterns were not detected by preformed combinations of orientation detectors or global templates with a single output. Instead, the crucial cue for detecting edges as radial or circular was the coincidence of responses of numerous local edge detectors having the appropriate convergence to a hub. Edges that converged towards a hub were detected by the bees as radial, and edges at right angles to these were parts of circles, irrespective of the actual pattern. Breaking the patterns of spokes or circles into rows of squares spoiled the discrimination if the squares were separately resolved. Alternatively, breaking the pattern into short bars that were separately resolved spoiled the discrimination when the bars subtended less than 3 degrees . The local feature detectors for spokes and circles therefore resembled those of the orientation detectors in being short, independent, and unable to span gaps of more than 3 degrees . In conclusion, radial and circular patterns were identified by the regional coincidences and convergence of local detectors of edge orientation, and the positions of the centres of symmetry were remembered as landmarks that helped locate the reward, but the patterns themselves were not remembered.