Adenylyl cyclase system of the small preovulatory follicles of the domestic hen: responsiveness to follicle-stimulating hormone and luteinizing hormone

The purpose of this study was to determine if the granulosa cells of the small preovulatory follicles of the domestic hen are a target tissue for follicle-stimulating hormone (FSH). The third largest (F3), fourth largest (F4), and fifth largest (F5) follicles were removed from hens at 20, 12, 6 and 2 h before ovulation of the F1 follicle. Basal, FSH- and luteinizing hormone (LH)-stimulable adenylyl cyclase (AC) activities were measured in the granulosa cells. Isolated granulosa cells of the F5 follicle, obtained 20 h before ovulation of the F1 follicle, were incubated with ovine (o) or turkey (t) FSH and progesterone (P4) was assayed in the medium. Basal AC activity was similar for F5, F4 and F3 granulosa cells except for an increase (P less than 0.01) in F3 follicles removed 2 h before ovulation of the F1 follicle. The FSH-stimulable AC activity of F5, F4 and F3 granulosa cells was elevated over basal (P less than 0.01). The greatest responsiveness was seen in the F5 follicle and the least in the F3 follicle. LH-stimulable AC activity was absent in the F5 follicle but present in the F4 and F3 follicles with the greater responsiveness in the F3 follicle. Isolated F5 granulosa cells secreted significant amounts of P4 in response to oFSH and tFSH. The data indicate that: 1) FSH stimulates the AC system of granulosa cells of the smaller preovulatory follicles (F5 greater than F4 greater than F3) while LH stimulates the AC system of granulosa cells of the larger follicles (F3 greater than F4), and 2) FSH promotes P4 production by granulosa cells of F5 follicles.(ABSTRACT TRUNCATED AT 250 WORDS)     

Interaction of wheat germ protein synthesis initiation factors eIF-3, eIF-(iso)4F, and eIF-4F with mRNA analogues

The interaction of wheat germ eIF-3 with the wheat germ cap-binding proteins eIF-(iso)4F and eIF-4F as a function of pH and ionic strength is described. Direct fluorescence titration experiments are used to measure the equilibrium association constants (Keq) for the binary protein/protein complexes as well as for the interaction of eIF-3 with methylated cap analogues and rabbit alpha-globin mRNA oligonucleotide analogues. The Keq values for ternary eIF-3/eIF-(iso)4F/analogue and eIF-3/eIF-4F/analogue interactions were also measured. The equilibrium binding constants were used to calculate coupling free energies, which provide an estimate of the cooperativity for the interaction of the mRNA analogues, eIF-3, and either eIF-4F or eIF-(iso)4F. These data suggest a mechanism in which the binding of eIF-(iso)4F or eIF-4F to mRNA enhances the subsequent binding of eIF-3 to the message. This may lead to favorable positioning of the complex on the ribosome and thereby enhance translation.     

Purification and characterization of the multiple forms of 3 alpha-hydroxysteroid dehydrogenase in rat liver cytosol

The presence of multiple forms of 3 alpha-hydroxysteroid dehydrogenase in the cytosol of male rat livers was demonstrated. The enzyme activity was separated into two fractions (F3 and F4) by DEAE-cellulose chromatography, and further fractionation of F3 into four (I-IV) and F4 into three (I-III) fractions was achieved by subsequent CM-Sephadex chromatography. Six forms (F3-II-IV and F4-I-III) were further purified by chromatofocusing and Red-Sepharose 4B chromatography. Two (F4-II and III) of the isolated enzymes were homogeneous, based on polyacrylamide gel electrophoresis. No shift of pI values was observed, when isoelectric focusing was performed with the F4 enzyme species in the presence of NAD(P)+ or NAD(P)H. All six enzyme species migrated closely with each other on dodecyl sulfate-polyacrylamide gel electrophoresis, from which the molecular masses were estimated to be 32 500 Da. Gel filtration gave similar values for the F4 enzyme species, indicating that each enzyme is a monomeric peptide. All enzyme species were able to catalyse the dehydrogenation of 3 alpha-hydroxysteroids (C19 to C26), and not C27 compound having a 1,5-dimethylhexyl side chain. The catalytic properties with steroids were very similar for five of the enzyme species, but F3-IV especially preferred androsterone. When male rat livers were used for isolation, the enzyme activity ratio of F3 to F4 for androsterone was about 1 to 8, whereas the ratio was about 1 to 20 for female rat livers. Considering the biosynthetic pathway of bile acids, the enzymes isolated here might play a specific role in the conversion of a 3 beta-hydroxy group to a 3 alpha-hydroxy group via a 3-oxo group of an intermediate in the synthesis of bile acids.     

Biosynthesis of the 2-(aminomethyl)-4-(hydroxymethyl)furan subunit of methanofuran

2H- and 13C-labeled precursors were used to establish the pathway for the biosynthesis of the 2-(aminomethyl)-4-(hydroxymethyl)furan (F1) component of methanofuran in methanogenic archaebacteria. The extent and position of the label incorporated into F1 were measured from the mass spectrum of the diacetyl derivative of F1. [1,2-13C2]Acetate was found to be incorporated into two separate positions of the F1 molecule as a unit. The extent of incorporation of 13C2 into each of these positions was the same as that observed for the incorporation of acetate into the alanine and proline produced by the cells. From [2,2,2-2H3]acetate, deuterium was incorporated into two separate sites of the F1 molecule, one containing up to two deuteriums and the other only one. On the basis of the fragmentation pattern of the F1 diacetyl derivative, it was determined that two deuteriums were incorporated into the hydroxymethyl group at C-4 and one was incorporated at C-3 of the furan ring. The extent and distribution of the incorporated deuterium at the C-4 methylene were the same as that observed for C-6 of the glucose produced by the cells. On the basis of this and additional information presented in this paper, it is concluded that F1 is generated by the condensation of dihydroxyacetone phosphate with pyruvate. The resulting dihydroxy-substituted tetrahydrofuran after elimination of 2 mol of water would produce the phosphate ester of 2-carboxy-4-(hydroxymethyl)furan. Reduction of the carboxylic acid to an aldehyde and subsequent transamination would produce the phosphate ester of F1.     

Microbial and xanthine dehydrogenase inhibitory activity of some flavones

Xanthine dehydrogenase (XDH) is responsible for the pathological condition called Gout. In the present study different flavones synthesized from chalcone were evaluated in vitro for their inhibitory activity. Inhibitory activity of flavones on XDH was determined in terms of inhibition of uric acid synthesis from Xanthine. The enzymatic activity was found maximum at pH 7.5 and temperature 40 degrees C. The flavones 6-chloro-2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F(1)) and 6-chloro-7methyl-2-[3-(4-chloro-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one(F(2)),were noncompetitive and competitive inhibitor with Ki values 1.1 and 0.22 respectively. The flavones (F(1)), (F(2)), 6-chloro-2-[3-(4-chloro-phenyl)-1phenyl-1-H-pyrazol-4-yl]-chromen-4-one(F(3)), 8-bromo-6-chloro-2-[3-(4-chloro-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F(4)), 2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F(5)) and 6-methyl-2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F(6)) were also screened for their antimicrobial activity, measured in terms of zone of inhibition. A broad spectrum antifungal activity was obtained against Trichoderma viridae, Candida albicans, Microsporum cannis, Penicillium chrysogenum and Fusarium moniliformae. In case of Aspergillus niger and Aspergillus flavous only spore formation was affected, while antibacterial activity was observed against Staphylococcus aureus, Bacillus subtilis and Serratia marsecens only. The flavones were further analyzed for quantitative structural activity relationship study (QSAR) by using PASS, online software to determine their Pa value. Toxicity and drug relevant properties were revealed by PALLAS software in terms of their molecular weight. Log P values were also studied. The result showed both the F(1) and F(2) flavones as antigout and therefore supports the development of novel drugs for the treatment of gout.     

Biological and Structural Characterization of Crotoxin and New Isoform of Crotoxin B PLA<Subscript>2</Subscript> (F6a) from <Emphasis Type="Italic">Crotalus durissus collilineatus</Emphasis> Snake Venom

A new crotoxin B isoform PLA₂ (F6a), from Crotalus durissus collilineatus was purified from by one step reverse phase HPLC chromatography using μ-Bondapack C-18 column analytic. The new crotoxin B isoform PLA₂ (F6a), complex crotoxin, the catalytic subunit crotoxin B isoform PLA₂ (F6a) and two crotapotin isoforms (F3 and F4), were isolated from the venom of Crotalus durissus collilineatus. The crotapotins isoforms F3 and F4 had similar chemical properties, the two proteins different in their ability to inhibit of isoforms of PLA₂ (F6 and F6a). The molecular masses estimated by MALDI-TOF mass spectrometry were: crotoxin B: 14,943.14 Da, crotapotin F3: 8,693.24 Da, and crotapotin F4: 9 314.56 Da. The new crotoxin B isoform PLA₂ (F6a) contained 122 amino acid residues and a pI of 8.58. Its amino acid sequence presents high identity with those of other PLA₂s, particularly in the calcium binding loop and active site helix 3. It also presents similarities in the C-terminal region with other myotoxic PLA₂s. The new crotoxin B isoform PLA₂ (F6a) contained 122 amino acid residues, with a primary structure of HLLQFNKMIK FETRRNAIPP YAFYGCYCGW GGRGRPKDAT DRCCFVHDCC YGKLAKCNTK WDFYRYSLKS GYITCGKGTW CEEQICECDR VAAECLRRSL STYRYGYMIY PDSRCRGPSE TC. A neuromuscular blocking activity was induced by crotoxin and new crotoxin B isoform PLA₂ (F6a) in the isolated mouse phrenic nerve diaphragm and the biventer cervicis chick nerve-muscle preparation. Whole crotoxin was devoid of cytolytic activity upon myoblasts and myotubes in vitro, whereas new crotoxin B isoform PLA₂ (F6a) was clearly cytotoxic to these cells.     

Novel quinazoline-quinoline alkaloids with cytotoxic and DNA topoisomerase II inhibitory activities

Two new synthetic analogues of luotonins A and F, 7-acetylaminoluotonin A (6) and 3-[3H(quinazolino-4-one)]quinoline (7) were synthesized. The new analogues, along with four natural quinazoline-quinoline alkaloids, luotonins A (1), B (2), E (3), F (4) and a synthetic deoxoluotonin F (5), showed cytotoxic activity (IC(50) 1.8-40.0 microg/mL) and DNA topoisomerase II inhibition at a concentration of 25 microM.     

Isolation and initial characterization of a bacterial consortium able to mineralize fluorobenzene.

Fluorinated compounds are known to be more resistant to microbial degradation than other halogenated chemicals. A microbial consortium capable of aerobic biodegradation of fluorobenzene (FB) as the sole source of carbon and energy was isolated by selective enrichment from sediments collected in a drain near an industrial site. A combination of three microbial strains recovered from the enriched consortium was shown to be necessary for complete FB mineralization. Two of the strains (F1 and F3) were classified by 16S rRNA analysis as belonging to the Sphingobacterium/Flavobacterium group, while the third (F4) falls in the beta-Proteobacteria group, clustering with Alcaligenes species. Strain F4 was consistently found in the liquid cultures in a much greater proportion than strains F1 and F3 (86:8:6 for F4, F1, and F3, respectively). Stoichiometric release of fluoride ions was measured in batch and fed-batch cultures. In batch cultures, the consortium was able to use FB up to concentrations of 400 mg liter(-1) and was able to utilize a range of other organic compounds, including 4-fluorophenol and 4-fluorobenzoate. To our knowledge this is the first time biodegradation of FB as a sole carbon source has been reported.     

D4F alleviates the C/EBP homologous protein-mediated apoptosis in glycated high-density lipoprotein-treated macrophages by facilitating autophagy

The present study aimed to investigate the role of D4F, an apolipoprotein A-I mimetic peptide, in macrophage apoptosis induced by the glycated high-density lipoprotein (gly-HDL)-induced endoplasmic reticulum (ER) stress C/EBP homologous protein (CHOP) pathway, and unravel the regulatory role of autophagy in this process. Our results revealed that except for suppressing the accumulation of lipids within RAW264.7 macrophages caused by gly-HDL, D4F inhibited gly-HDL-induced decrease in the cell viability and increase in lactate dehydrogenase leakage and cell apoptosis, which were similar to 4-phenylbutyric acid (PBA, an ER stress inhibitor). Besides, similar to PBA, D4F inhibited gly-HDL-induced ER stress response activation evaluated through the decreased PERK and eIF2α phosphorylation, together with reduced ATF6 nuclear translocation as well as the downregulation of GRP78 and CHOP. Interestingly, D4F facilitated gly-HDL-triggered activation of autophagy, measured as elevated levels of beclin-1, LC3-II, and ATG5 expressions in macrophages. Furthermore, the inhibition effect of D4F on gly-HDL-induced ER stress-CHOP-induced apoptosis of macrophages was restrained after beclin-1 siRNA and 3-methyladenine (3-MA, an inhibitor of autophagy) treatments, while this effect was further reinforced after rapamycin (Rapa, an inducer of autophagy) treatment. Furthermore, administering D4F or Rapa to T2DM mice upregulated LC3-II and attenuated CHOP expression, cell apoptosis, and atherosclerotic lesions. However, the opposite results were obtained when 3-MA was administered to these mice. These results support that D4F effectively protects macrophages against gly-HDL-induced ER stress-CHOP-mediated apoptosis by promoting autophagy.     

Evidence that the 5'-untranslated leader of mRNA affects the requirement for wheat germ initiation factors 4A, 4F, and 4G

The efficiency of translation of alfalfa mosaic virus (AMV) RNA 4, barley alpha-amylase (B alpha A) mRNA, and two chimeric mRNAs, AMV 4-B alpha A and B alpha A-AMV 4 (in which the 5' leader sequences of the two mRNAs were interchanged), was measured in an S30 extract from wheat germ and a fractionated system from wheat germ in which translation could be made dependent upon initiation factor (eIF) 3, 4A, 4F, or 4G. In the S30 system, AMV RNA 4 and the chimeric mRNA AMV 4-B alpha A are translated much more efficiently than B alpha A mRNA and the chimeric mRNA B alpha A-AMV 4. When the S30 system was supplemented with high amounts of purified eIF-3, eIF-4A, eIF-4F, and eIF-4G, B alpha A and B alpha A-AMV 4 mRNAs were translated as efficiently as AMV RNA 4 and AMV 4-B alpha A mRNA. These findings indicated that the mRNAs containing the B alpha A leader sequence required higher amounts of one or more of the initiation factors (eIF-3, eIF-4A, eIF-4F, and eIF-4G) for efficient translation. Determination of the amounts of the initiation factors required for translation in the fractionated system showed that AMV RNA 4 required 2-4-fold lower amounts of eIF-3, eIF-4A, eIF-4F, and eIF-4G than did B alpha A mRNA. Replacement of the B alpha A leader sequence with that of AMV RNA 4 decreased the amounts of eIF-4A, eIF-4G, and eIF-3 required, but did not affect the amount of eIF-4F required. Replacement of the AMV RNA 4 leader sequence with that of B alpha A mRNA increased the amounts of eIF-4F, eIF-4G, and eIF-3 required, but did not affect the amount of eIF-4A required. These data strongly suggest that the amounts of the factors required are affected not only by the 5' leader itself but also by interactions between the 5' leader and a region(s) of the mRNA 3' to the initiation codon.     

Effects of semicarbazide on DNA, RNA and protein hepatic levels on four subsequent generations of Wistar rats

1. The offspring (F1) of a parent generation (P) were mated on a brother-to-sister system to produce a second generation (F2), which was then mated in the same way to produce a third generation (F3). 2. Each of these generations were divided into two groups, controls and treated. 3. A single dose of 100 mg/kg of semicarbazide was administered to the treated Wistar rats on the 10th day of their pregnancy. 4. DNA, RNA and protein hepatic levels were measured in the livers of either 21-day-old foetuses or 1, 7, 15 or 30-day-old offspring. 5. These levels were also studied in the pregnant rats on day 21 of gestation. 6. Semicarbazide produced a significant decrease of these levels not only in the foetuses, offspring and pregnant rats but also in the controls, F2 and F3, from treated P and F1 respectively.     

NADPH oxidase 4 regulate the glycolytic metabolic reprogramming of microglial cells to promote M1 polarization

This work aimed to investigate the role and mechanism of NADPH oxidase 4 (NOX4) in the polarization of microglial cells. Microglial cells were transfected with the NOX4 overexpression plasmid (pGL3-NOX4), and later treated with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) to induce its M1 polarization. Later, the F4/80 + CD86 + cell proportion was detected by flow cytometry (FCM), the inflammatory factor expression levels were analyzed through enzyme-linked immunosorbent assay (ELISA), while ionized calcium binding adapter molecule 1 (IBA-1) and PKM2 expression were measured by immunofluorescence (IF) staining. In addition, dichlorodihydrofluorescein diacetate probe was utilized to detect the reactive oxygen species (ROS) levels, glucose uptake, and glycolysis, as well as lactic acid level. The expression of glycolytic enzymes PKM2, HK2, and citrate (Si)-synthas (CS) was detected by Western-blot (WB) assay. Moreover, the polarization level of microglial cells was detected after ROS expression was suppressed by the ROS inhibitor N-acetylcysteine (NAC). In mouse experiments, LPS was applied in inducing central neuroinflammation in NOX4 knockdown mouse model (KO) and wild-type mice (WT). Thereafter, the inflammatory factor levels and lactic acid level in mouse tissues were detected; IBA-1 and CD86 expression in mice was measured by IF staining; and the expression of glycolytic enzymes PKM2, HK2, and CS in the central nervous system (CNS) was also detected. After NOX4 overexpression in microglial cells, the M1 polarization level was upregulated, the F4/80 + CD86 + cell proportion increased, and inflammatory factors were upregulated. At the same time, the expression of glycolytic enzymes PKM2, HK2, and CS was upregulated. NAC pretreatment suppressed the effects of NOX4, reduced the F4/80 + CD86 + cell proportion, and suppressed the expression of PKM2, HK2, and CS. In the mouse model, the expression levels of CD86 in KO group decreased, and the inflammatory factors were also downregulated. NOX4 promotes glycolysis of microglial cells via ROS, thus accelerating M1 polarization and inflammatory factor expression. In this regard, NOX4 is promising as a new target for the treatment of neuroinflammation.     

Decreased granulosa cell luteinizing hormone sensitivity and altered thecal estradiol concentration in the aged hen, Gallus domesticus

Few studies have examined the effect of age on the ovulation cycle of the hen. Our aim was to determine if changes in the ovary account for the decrease in egg production with age. Young hens (28-38 wk of age) laying at least 20 eggs per sequence and old hens (53-63 wk of age) laying 3-6 eggs per sequence were used. We determined luteinizing hormone (LH) sensitivity of the ovary of young and old hens by measuring LH stimulable adenylyl cyclase (AC) activity of the granulosa layer. We also measured theca- and granulosa-layer weights and steroid concentrations of these layers and of the serum in young and old hens. Mean basal AC activity (pg/min/mg protein) for the largest (F1) and second largest (F2) follicles from young and old hens did not differ. A significant dose-response relationship to LH was present in all groups, and AC responsiveness to increasing doses of LH was greater in the F1 and F2 follicles of young hens than in the same follicles of old hens. The F4 and F5 follicles of young hens had a significantly greater estradiol (E2) concentration (pg/mg theca protein) compared to old hens, while the E2 concentration in the F2 follicle was greater in old hens. The theca layer of the F1 follicle of old hens weighed significantly more than that of young hens, whereas the theca layer of the F3, F4 and F5 follicles from young hens weighed more than those of old hens.(ABSTRACT TRUNCATED AT 250 WORDS)     

Alterations in follicular IGFBP mRNA expression and follicular fluid IGFBP concentrations during the first follicle wave in beef heifers

The objective was to determine the pattern of IGFBP-2, -3 and -4 gene expression and follicular fluid concentrations of IGFBP-2, -3, -4 and -5 during emergence, selection and dominance of the first follicle wave of the estrous cycle in cattle and during exogenous steroid treatment. Heifers (n = 35) were ovariectomized at 36 (n = 7), 66 (n = 8), 84 (n = 12) and 108 (n = 8) h after the onset of estrus. Heifers in the 84 h ovariectomy group were sub-divided to receive either no treatment (n = 6) or were treated with a progesterone-releasing intravaginal device (n = 6, PRID) and 0.75 mg estradiol benzoate i.m. at the approximate time of ovulation, 30 h post estrus until ovariectomy. Within heifers the four largest follicles recovered following ovariectomy were ranked on size (F1, F2, F3 and F4). At 36 h IGFBP gene expression and follicular fluid IGFBP concentrations were similar in all follicles (F1-F4). Mean diameter of the F1 follicle increased (P < 0.05) between 36 and 84 h with no difference between 84 and 108 h. The F1 follicle had the highest (P < 0.05) concentration of estradiol compared with the F2, F3 and F4 at 84 and 108 h. There was no granulosa cell IGFBP-2 mRNA in F1 follicles at 84 or 108 h. Intrafolliclar IGFBP-2 concentrations were lower (P < 0.05) in the F1 compared with F3 and F4 follicles at 108 h. There was no difference in theca cell IGFBP-4 mRNA expression at 108h, but amounts of follicular fluid IGFBP-4 were lower (P < 0.05) in F1 follicles compared with F3 and F4 follicles at 108 h. IGFBP-3 mRNA was localized in the theca layer of all follicles examined with no difference in expression or follicular fluid concentrations during emergence, selection and dominance of the first follicle wave. IGFBP-5 concentrations were higher (P < 0.05) in follicular fluid of F3 follicles at 108 h compared with the F3 at 36 h. In conclusion follicular dominance was associated with low or decreased follicular fluid concentrations of IGFBP-4 and -5, increased estradiol and differential regulation of IGFBP production.     

Alterations in intrafollicular regulatory factors and apoptosis during selection of follicles in the first follicular wave of the bovine estrous cycle

Changes in follicular fluid (FF) concentrations of estradiol, inhibin forms, and insulin-like growth factor binding proteins (IGFBPs), percentage of apoptotic granulosa cells (%A), and follicular size for individual follicles in a growing cohort were determined throughout the first wave of follicular development during the bovine estrous cycle and related to FSH decline. Four groups of heifers (n = 31) were ovariectomized between Days 1.5 and 4.5 of the estrous cycle at 5 +/- 1, 33 +/- 2, 53 +/- 1, and 84 +/- 2 h after the periovulatory peak in FSH concentrations. Follicles > or = 2.5 mm were dissected, measured, and FF aspirated. The five largest follicles were ranked based on their diameter (F1 to F5). Diameters of F1 to F5 were positively correlated with interval from FSH peak (r > or = 0.6, P < 0.05). Five hours after the FSH peak, follicular diameter and FF concentrations of estradiol, inhibins, and IGFBPs were similar for F1 to F5. From 5 to 33 h, amounts of the six precursor inhibin forms (> or = 48 kDa) increased (P < 0.05) in F1 follicles. The IGFBPs in F1 follicles remained low at all time periods. At 33 h, amounts of IGFBP-4 and -5 were higher (P < 0.05) in F4 and F5 compared with F1 follicles. At 84 h, IGFBP-2, -4, and -5 were increased (P < 0.05) in F3, F4, and F5 compared with F1. At 5, 33, or 53 h, %A was not different between follicles in any size class. At 84 h %A was increased (P < 0.05) in follicles <6 mm in diameter. However, at that time, %A did not differ between the selected DF and the largest subordinate follicle. For individual heifers, the selected DF at 84 h was largest in size, highest in estradiol, and lowest in IGFBP-2 and -4. The F1 follicle had highest estradiol in 23 of 27 heifers irrespective of stage of the wave and lowest IGFBP-4 in 19 of 21 heifers from 33 h. We concluded that the earliest intrafollicular changes that differentiate a dominant-like follicle from the growing cohort are enhanced capacity to produce estradiol and maintenance of low levels of IGFBPs.     

Purification of the oligosaccharide-cleaving enzymes of Flavobacterium meningosepticum.

Four oligosaccharide chain-cleaving enzymes, including two new endoglycosidases distinct from endo-beta-acetylglucosaminidase (Endo) F1, have been identified and purified to homogeneity from cultural filtrates of Flavobacterium meningosepticum. FPLC-directed hydrophobic-interaction chromatography in conjunction with high-resolution ion-exchange chromatography provided a more simple, rapid method for the isolation of endoglycosidase F1, F2 and F3, and the amidase, peptide-N4-N-acetyl-beta-D-glucosaminyl)-asparagine amidase (PNGase F), in greater than 50% yield. The specificity of PNGase F and Endo F1 are well established. Endo F2 and Endo F3 represent new distinct endoglycosidases that prefer complex as compared to high-mannose asparagine-linked glycans. Endo F2 cleaved biantennary oligosaccharides, whereas Endo F3 cleaved both bi- and triantennary oligosaccharides.     

Preservation of biological function despite oxidative modification of the apolipoprotein A-I mimetic peptide 4F

Myeloperoxidase (MPO)-derived hypochlorous acid induces changes in HDL function via redox modifications at the level of apolipoprotein A-I (apoA-I). As 4F and apoA-I share structural and functional properties, we tested the hypothesis that 4F acts as a reactive substrate for hypochlorous acid (HOCl). 4F reduced the HOCl-mediated oxidation of the fluorescent substrate APF in a concentration-dependent manner (ED(50) ～ 56 ± 3 μM). This reaction induced changes in the physical properties of 4F. Addition of HOCl to 4F at molar ratios ranging from 1:1 to 3:1 reduced 4F band intensity on SDS-PAGE gels and was accompanied by the formation of a higher molecular weight species. Chromatographic studies showed a reduction in 4F peak area with increasing HOCl and the formation of new products. Mass spectral analyses of collected fractions revealed oxidation of the sole tryptophan (Trp) residue in 4F. 4F was equally susceptible to oxidation in the lipid-free and lipid-bound states. To determine whether Trp oxidation influenced its apoA-I mimetic properties, we monitored effects of HOCl on 4F-mediated lipid binding and ABCA1-dependent cholesterol efflux. Neither property was altered by HOCl. These results suggest that 4F serves as a reactive substrate for HOCl, an antioxidant response that does not influence the lipid binding and cholesterol effluxing capacities of the peptide.     

Multiple lipid interactions of the Sendai virus fusogenic protein

The membrane topology of the envelope of Sendai virus was investigated using various radioactive photoactivable hydrophobic reagents: 3-(trifluoromethyl)-3-(m-[125I]iodophenyl)diazirine and the two phospholipid analogues, 1-palmitoyl-2-(2-azido-4-nitro)benzoyl-sn -glycero-3- phospho[3H]choline and 1-myristoyl-2,12-amino-(4-N-3-nitro-1-azidophenyl)dodecanoyl-sn-glycero- 3-phospho[14C]choline. The hemagglutinin-neuraminidase glycoprotein and the fusogenic (F) glycoprotein were labeled by all three probes, confirming that these proteins are integral components of the viral envelope. The labeled F glycoprotein, composed of the two subunits F1 and F2, was cleaved in situ with trypsin to yield two fragments, F32 (32 kDa) and F19 (19 kDa). F2 was not labeled by any of the probes, suggesting an external location; whereas F19 was labeled by all probes and hence contains the portion of the F glycoprotein which traverses the viral envelope. Fragment F32 reacted both with 3-(trifluoromethyl)-3-(m-[125I]iodophenyl)diazirine and with 1-palmitoyl-2-(2-azido-4-nitro)benzoyl-sn-glycero-3-phospho[3H]choline, but not with 1-myristoyl-2,12-amino-(4-N-3-nitro-1-azidophenyl)dodecanoyl-sn-glycero- 3- phospho[14C]choline. This result opens the possibility that the F glycoprotein is formed by a loop-like structure having multiple interactions with viral lipids.     

Isolation of new cytotoxic metabolites from Cleome droserifolia growing in Egypt

The sulforhodamine B (SRB) assay was used to assess the cytotoxicity of the aqueous (AqEx) and ethanolic (AlEx) extracts, respectively, of the aerial parts of Cleome droserifolia (Forssk.) Del. against two human cancer cell lines, breast (MCF7) and colon (HCT116) adenocarcinoma. AqEx exhibited higher cytotoxic activity, thus its four subfractions, namely n-hexane (HxFr), chloroform (ClFr), ethyl acetate (EtFr), and n-butanol (BuFr) fractions, were also tested. Purification of the more active ClFr and EtFr yielded nine compounds. Six terpenoids, guai-7(11),8-diene (C1), 1-hydroxy-guai-3,10(14)-diene (C2), 18-hydroxydollabela-8(17)-ene (C3), (24E)-stigmasta-5,8-dien-3beta-ol (C4), teucladiol [1alpha,5beta-guai-10(14)-ene-4beta,6beta-diol] (C5), and buchariol (4,10-epoxy-6a-hydroxyguaiane) (C6), were isolated from ClFr and three flavonol glycosides, isorhamnetin-3-O-beta-D-glucoside (F1), quercetin-3'-methoxy-3-O-(4"-acetylrhamnoside)-7-O-alpha-rhamnoside (F2), and kaempferol-4'-methoxy-3,7-O-dirhamnoside (F3), were isolated from EtFr. Compounds C3 and F2 are new in nature. The isolated compounds were identified using various spectroscopic methods (UV, IR, 1H NMR, 13C NMR, HMQC, HMBC, and COSY). Compounds C1, C3, F2, and F3 showed significant cytotoxic activities against the two tested cell lines comparable to those of the anticancer drug doxorubicin. The new compound C3 was the most active as it had the lowest IC50 values, (1.9 +/- 0.08) and (1.6 +/- 0.09) microg/ml corresponding to 6.5 and 5.4 microM, against MCF7 and HCT116 cells, respectively.     

Father-male offspring transmission of seasonal variations in testicular diameter and percentage of abnormal sperm in the Ile-de-France ram. 1. Male offspring born in February

An experiment was conducted on the Ile-de-France (IF) breed to determine if the more or less important sensitivity of the ram to photoperiodism came under genetic control. Five base breed unrelated rams (greater than or equal to 4 yr old), were chosen for this study: 2 good (I and II), 2 bad (III and IV), and an intermediate sire (V). Ram I, which died a few years before the experiment began, was selected on both the low amplitude of its sperm production during a 6-month period of artificial lighting and the very high fertilizing capacity of its sperm in spring. Rams II to V were controlled for 12 (percentage of morphologically abnormal spermatozoa, AM) or 14 (maximum antero-posterior scrotal diameter of both testes, DT) consecutive months. Following this period of control, seasonal variation in rams was assessed as follows: low (ram II), high (rams III and IV) and intermediate (ram V) seasonal variation rams. Breeding (artificial insemination) of these 5 rams to IF ewes resulted in 18 male offspring born in February and distributed as follows: rams I to III: 4 male offspring/ram (families 1 to 3, F1 to F3), rams IV and V: 3 male offspring/ram (families 4 and 5, F4 and F5). The 18 animals were controlled once a week (DT and AM) from 8, 5 to 46 months of age (7 periods, P1 to P7). Regarding DT, mean DT was higher in F1 and F2 than those of the whole population (WP) (represented by a discontinuous line of ordinate 5.0 in Graph 3), but F2 was closer to this population than F1. On the other hand, they were lower in the rams of F3 and F4. Differences between F3 or F4 and WP were lower in autumn than in spring. All families showed significant differences during the experimental periods except at P7 for pairs 3-5 and 4-5. Distances between F1, F2, F3 were always different (P less than 0.01 or P less than 0.001), whatever the size of the population (n = 3 or 4). Weekly F5 values varied in an opposite way to those of F3 and F4: increase in spring and decrease in autumn. Regarding AM, families did not differ as much as in DT (graph 4). Weekly variations in AM were also stronger. However, mean AM was almost always lower in F1 males and somewhat higher in F3 males to that of WP.(ABSTRACT TRUNCATED AT 400 WORDS)