G1 Samples Research Articles

Electrical conductivity, relaxation, and scaling analysis studies of lithium alumino phosphate glasses and glass ceramics

Different compositions of lithium aluminum phosphate glasses were prepared by melt quenching technique. The best bulk conductivity achieved by the sample G3, (28 mol% of lithium oxide). Further, the investigation extended by crystallizing the G3 sample at different temperatures, 200 °C (GC200), 300 °C(GC300), 400 °C (GC400), and 500 °C (GC500). The electrical measurements for all the glasses and glass ceramics were carried out in the frequency range of 1–105 Hz and at a temperature range of 393–513 K by the impedance spectroscopy. The variation of conductivity with frequency of the samples was explained in the light of different valency states of aluminum ions. AC conductivity data are fitted to a power law equation. Scaled spectra for ac conductivity and modulus data suggested that the present glass samples follow temperature independent conductivity distribution relaxation mechanism.

176 GENE EXPRESSION OF LUTEINIZING HORMONE RECEPTOR (LHR) ISOFORMS IN GRANULOSA CELLS OF FOLLICLES FROM NELLORE HEIFERS BEFORE, DURING, AND AFTER FOLLICULAR DEVIATION

During bovine follicular development, there is a phase known as follicular deviation in which the future dominant follicle grows faster than the other follicles and acquires LH receptors (LHR). In Nellore breed, deviation occurs 2.5 days after ovulation, and at this time, the dominant follicle has in average a diameter of 6.0 mm. Some authors believe that LHRs are present in the future dominant follicle before deviation and are essential for this process. However, others are convinced that LHRs are present only during or after follicular deviation. The aim of the present experiment was to evaluate the expression of 4 LHR isoforms (M1 to M4) in granulosa cells of follicles from Nellore heifers before, during, and after follicular deviation. At a random stage of the estrous cycle (D0), Nellore heifers (n = 21) received a progesterone intravaginal device (1.0 g, Primer®, Tecnopec, Sao Paulo, Brazil) and 2.5 mg of estradiol benzoate (EB, i.m., Estrogin®, Farmavet, Sao Paulo, Brazil). Eight days later (D8) PGF2α was administered (150 μg d-cloprostenol, i.m., Prolise®, ARSA S.R.L., Buenos Aires, Argentina), and the device was removed. Twenty-four hours after device removal, cows were treated with EB (1.0 mg, i.m.), and from this point in time, the growth of the dominant follicle growth was observed by ultrasonography (US, Aloka 900, Tokyo, Japan) every 12 h. The animals were allocated in 3 groups: Group 2 (G2, 2 days after ovulation, n = 7), Group 2.5 (G2.5, 2.5 days after ovulation, n = 7), and Group 3 (G3, 3 days after ovulation, n = 7), and were slaughtered 2, 2.5, and 3 days after ovulation, respectively, in order to remove the ovaries. The granulosa cells, obtained from ovarian follicles, were separated for total RNA extraction, and the gene expression of LHR isoforms was measured by semiquantitative RT-PCR. Since LHR expression was not detected in Group 2 (follicles with 4.5 to 6.7 mm), comparisons were performed between groups G2.5 and G3 by ANOVA. The LHR expression was detected only in 2 samples of Group G2 (7.0-mm follicles) and was significantly higher in Group G3 (63.6%; follicles from 8 to 14 mm, P < 0.05). In all samples that expressed LHR, the 4 isoforms were present. It is concluded that LHR expression is present in granulosa cells of follicles from Nellore heifers after follicular deviation. Support and fellowship from FAPESP (Sao Paulo, Brazil).We are grateful to Tecnopec (Sao Paulo, Brazil) for providing intravaginal devices used in the experiment.

Bacterial leakage in root canals filled with calcium hydroxide paste associated with different vehicles

This in vitro study evaluated, using a bacterial leakage model, whether intracanal medication with calcium hydroxide [Ca(OH)2]-based pastes prepared with different vehicles, has inhibitory effect on corono-apical leakage of bacteria. Forty instrumented human canines were dressed with Ca(OH)2 p.a. associated with: G1 = distilled water; G2 = polyethylene glycol (PG); G3 = PG + CMCP; and G4 = glycerin. Five teeth with intact crowns served as negative controls and 5 instrumented teeth without temporary dressing served as positive controls. All teeth were mounted in a 2-chamber apparatus and then exposed to human saliva for 63 days. Leakage was recorded when turbidity was observed in the lower chamber. Fifty percent of the samples of G1 and G2, 10% of G3 and 80% of G4 were fully contaminated after 9 weeks. Statistically significant differences were observed with paired comparisons G3 and G4 (p=0.0069), with G3 achieving better seal against bacterial leakage than G4.

Interference of vaccinal antibodies on serological diagnosis of leptospirosis in vaccinated buffalo using two types of commercial vaccines

The vaccinal antibodies interference represents one of the Microscopic Agglutination test - MAT limitation in the animal leptospirosis serum diagnosis. Prospective studies showing the dimensions of this effect are rare in buffaloes. This study aimed to determine the anti-Leptospira serum agglutinin profile in vaccinated female buffaloes using two types of commercial vaccines against leptospirosis: bacterin (whole bacterial cell) and purified outer membrane and to evaluate the vaccinal interference on serum diagnosis. Three groups of 11 adult buffalo females were established: G1-control, non-vaccinated, G2- vaccinated with bacterin vaccine with six serovars, G3- outer membrane purified vaccine with five serovars. A booster dose was administrated 30 days after the first vaccination (dpv) and two re-vaccinations six months a part (210 and 390 dpv). Serum samples were collected on days 0, 15, 40, 45, 60 and every 30 days until 540 dpv. G1, G2 and G3 serum samples were submitted to MAT with the serovars present in the vaccines. G1 remained always negative. Both vaccines induced serologic responses in MAT at 150 dpv against all serovars and they revealed maximum titers around 45 and 60dpv as follows: Pomona: G2 (1600) and G3 (3200); Hardjo: G2 and G3 (1600); Wolffi: G2 (800) and G3 (1600); Icterohaemorrhagiae: G2 and G3 (800); Grippotyphosa: G2 and G3 (200) and Canicola: G2 (NR) and G3 (400). Even though, the Wolffi serovar is not present in the purified outer membrane vaccine, G3 showed a response to that serovar, probably due to cross reaction to the serovar Hardjo. The G3 titers were higher and appeared earlier than in G2, but with similar serologic profiles. At the re-vaccination there was an increase on agglutinin levels, but of less intensity than those previously observed. After six months from the second revaccination (540 dfv), G2 and G3 were almost negative, which demonstrated the short diagnostic interference.

Sc-doping and A-site deficiency effects on the structure and magnetic properties of La 0.7Sr 0.3−yMn 1−xSc xO 3 lanthanum manganites

A study of the single-phase La 0.7Sr 0.3− y Mn 1− x Sc x O 3 A (=La, Sr)-site deficiency and B (=Mn, Sc)-site substituted manganites is presented. All the compositions belong to the R 3 ¯ c rhombohedral space group. Three groups of samples, G1 ( y=0; x=0–0.05), G2 ( x=0, y=0–0.03), and G3 ( x= y=0–0.03) show the continuous change of structure parameters and decrease in Curie temperature, T C, with the Sc content or/and deficiency in A-position. The cell parameters and cell volume increase with x and y in G1 and G3 sample groups. The lattice c-parameter decreases while the a-parameter and cell volume increase with y in G2 sample group. The decrease in the T C in the G1 group is mostly caused by the destruction of e g electron pathway because of a difference in electron configuration of Mn 3+ and Sc 3+ ions, and partially by the lattice distortion because the larger Sc 3+ ion than the Mn 3+ ion.

Conidial morphology and ecological characteristics as diagnostic tools for identifying Claviceps purpurea from salt-marsh habitats

Claviceps purpurea associated with grass hosts in salt-marsh habitats, also known as G3 ergot, can be differentiated from C. purpurea infecting grasses in other habitats, using genetic, chemical, and morphological criteria. However, only morphological analysis can be preformed on herbarium specimens, which should not be destroyed, or older samples that cannot be grown in culture. To determine if conidial characteristics could be employed to identify the three infraspecific groups of C. purpurea (G1–G3), sclerotia from terrestrial grasses (G1), moist habitats (G2), and salt-marsh habitats (G3) were examined. All G1 sclerotia sank in water. All G3 sclerotia floated in water, except those from Washington State, which had variable buoyancy characteristics. Group 2 sclerotia did not float in water, except those collected from Calamagrostis nutkaensis and Ammophila breviligulata. Based on the length of conidia derived from a plant host, G1 samples are indistinguishable from G2 samples but are significantly different from G3. Conidia produced in culture were on average smaller than conidia produced on plant hosts. These results indicate that ecological and conidial characteristics can be used to distinguish G3 from G1, but cannot consistently separate either from G2.

G2 rotavirus infections in an infantile population of the South of Italy: Variability of viral strains over time

Rotavirus positive samples collected in Palermo, Italy, during 2002-2004 did not react with the G2 type-specific RV5:3 monoclonal antibodies (MAbs) and could be identified as G2 only by RT-PCR genotyping. The genetic variation of VP7 and VP4 antigenic proteins was studied in 14 G2 samples including a selection of both those successfully characterized by serotyping and those failing to be serotyped. The phylogenetic analysis performed on partial VP7 sequences showed a temporal clustering of these strains, with those isolated in Palermo in 2003 belonging to the same lineage of G2 MAbs-unreactive strains identified in UK in 1996-1997 and in Bari, Italy, in 2003-2004. A single amino acid substitution in VP7 antigenic region A, at position 96 (Asp-->Asn), was consistently associated with the loss of antigenic reactivity. Five of the G2 strains were further characterized by sequencing of VP4-encoding genes as belonging to the P[4] type, and separate lineages clustering the strains according to a temporal distribution could be described. VP7 and VP4 antigenic proteins analysis provided evidence that over the last 11 years, at least two different populations of G2P[4] rotavirus strains have been infecting the infant population in Palermo. Considering the role of anti-VP7 and anti-VP4 neutralizing antibodies in rotavirus immunity, the emergence of new VP7-VP4 gene combinations might influence rotavirus circulation in the infant population and should be taken into consideration when devising vaccination strategies.

Molecular analysis ofVP4,VP7, andNSP4 genes of P[6]G2 rotavirus genotype strains recovered from neonates admitted to hospital in Belém, Brazil

This investigation describes the molecular characterization of P[6]G2 rotavirus strains from hospitalized neonates with community-acquired diarrhea (CAD), nosocomial diarrhea (ND), and asymptomatic nosocomial infection (ANI) in Belém, Brazil. Twenty-six rotavirus strains with P[6]G2 genotype were sequenced to genes coding for VP4, VP7, and NSP4 proteins. Phylogenetic analysis of the VP4 gene, including prototype strains RV3, ST3, M37, and U1205, showed that local P[6]G2 strains clustered forming a distinct lineage (bootstrap of 99%). Brazilian P[6]G2 strains had the highest homology (ranging from 96.0%-98.3%) with the African strain GR1107, G4P[6]. Phylogenetic tree for VP7 gene was constructed including old and new G2 African strains SA3958GR/97, SA356PT/96, SA514GR/87, SA4476PT/97, BF3676/99, GH1803/99, and representative strains of G1, G3, G4, G5, G8, and G9 genotypes. The Brazilian P[6]G2 samples fell into a distinct group (bootstrap value of 97%) and showed homology rates ranging from 92.1% to 93.5% with P[6]G2 African strains BF3676/99, GH1803/99, and SA3958GR/97. Nucleotide sequence analysis of the NSP4 gene, including human prototype strains S2, KUN, DS-1, RV5, RV3 and ST3, and animal prototype OSU, showed that all neonatal isolates fell into genotype A and clustered with a bootstrap value of 100%, with in-group similarities ranging from 99.3% to 100%. In this study no significant differences in nucleotide sequences of the VP4, VP7, and NSP4 genes could be observed when comparing diarrheic (CAD and ND) and non-diarrheic (ANI) babies. Monitoring of rotavirus strains in hospital environments is of particular importance, since it is claimed currently that an efficacious rotavirus vaccine, when available for routine use, will determine an impact on hospital-acquired rotavirus disease.

Evaluation of products from embryo culture and their correlation with pregnancy outcome

Evaluation of products from embryo culture and their correlation with pregnancy outcome

Intergenerational Continuity of Hostile Parenting and its Consequences: The Moderating Influence of Children's Negative Emotional Reactivity

The present study examined both the intergenerational transmission of hostile parenting as well as the moderating effects of child negative emotional reactivity on continuity across generations. The study also considered the link between hostile parenting in the second generation and problem behaviors in the third. Observational ratings of mothers’ hostile parenting in the first generation (G1) when the target participant was an adolescent (G2) predicted observational ratings of G2 hostile parenting toward their young child several years later (G3). G2 hostile parenting was positively related to behavior problems in the G3 sample. Moreover, intergenerational continuity in hostile parenting was evident only when G3 children were rated as highly reactive and emotionally negative during an observational arm restraint task, suggesting that child negative reactivity may condition intergenerational stability in parent hostility. Although the moderating effect was not significant statistically, a similar trend was evident for the link between G2 parenting and G3 problem behavior.

Association between freezing agent and acrosome damage of human spermatozoa from subnormal and normal semen

This experimental study compares the effects of human sperm preservation medium (HSPM) with TEST-yolk buffer (TYB) as cryoprotectants of human spermatozoa with respect to the integrity of the acrosome after the freeze-thawing procedure. Fifty-six semen samples were included in this study; 18 were subnormal (G1) and 38 were normal (G2) based on World Health Organization criteria, except for morphology, which was evaluated according to strict criteria. Each semen sample was divided into two parts: the first part was prepared for cryopreservation by the addition of HSPM (1:1) and the second by addition of TYB (1:1). Freezing was performed in liquid nitrogen vapour. Smears were made before freezing and after the thawing process for evaluation of acrosome integrity using fluorescent-lectin labelling. The mean percentage of spermatozoa with intact acrosomes in the subnormal group was 77.0 +/- 7.2% before freezing and decreased significantly (P < 0.001) after thawing: to 63.7 +/- 8.2% with the use of HSPM and 66.8 +/- 8.7% with the use of TYB. The corresponding values in the normal semen samples were 83.4 +/- 9.2%, 76.0 +/- 8.8% and 77.9 +/- 9.2%, respectively. It is obvious that the decrease in the mean percentage of spermatozoa with intact acrosome was significantly higher when using HSPM in comparison with TYB, not only for G1 (-14.9 +/- 1.9% versus -11.8 +/- 1.4%) but also for G2 samples (-13.8 +/- 1.5% versus -11.9 +/- 1.3%). In conclusion, TYB should be recommended for freeze-thawing of human spermatozoa as the first-choice cryoprotectant, for normal as well as subnormal semen samples, in order to protect the sperm acrosome from the deleterious effects of the freeze-thawing procedure.

Genetic variation in wild and hatchery stocks of the black pearl oyster, Pinctada margarififera, from Japan

The analysis of samples from the first to the third generations of hatchery stocks (G1, G2, G3), of black pearl oysters, P. margaritifera, has been investigated using 18 protein loci to determine the genetic variation compared to a wild sample (WS). A reduction of 17% and 18% in the number of alleles was estimated in G2 and G3, respectively. Seven alleles (of the total of 45 alleles) were not found in the wild sample. The change of selective constraints in hatcheries compared to the wild environment can account for these new alleles. The observed heterozygosities were maintained (Ho: wild=0.237 and hatchery=0.236 to 0.269). Inbreeding depression did not occur in any hatchery sample although an increasing excess of heterozygotes was observed in G2 and G3 samples. This could be explained by selective effects through the choice of broodstock and change of the selective forces in an artificial environment.

Wolinella recfa in adult gingivitis and periodontitis

Wolinella recta has been associated with adult periodontitis, but its role in the disease remains uncertain. This report clarifies the distribution of W. recta in periodontally healthy and diseased subjects, and treated patients with recurrent disease. A specific polyclonal rabbit antiserum against W. recta strain 372 was used for indirect immunofluorescence localization of W. recta in dental plaque from untreated and treated patients. Supragingival plaque was collected from 15 periodontally healthy individuals (H), 10 adults with mild gingivitis (G1), 8 with severe gingivitis (G2) and 15 with periodontitis (AP). Subgingival samples from 23 diseased sites (G2 and AP) were examined as well. There was a significant difference (p = 0.000) between the proportions of W. recta in subgingival (4.4%) vs. supragingival (0.3%) plaque samples from AP. A significant difference (p = 0.000) in W. recta proportions was also detected between subgingival plaque samples of AP (4.4%) vs. G2 (1.2%). No significant difference in the mean % of W. recta was found between supragingival plaque of AP (0.3%) and G2 (0%), and samples of G1 (0.01%) and H (0.1%). In a separate study, 85 adults previously treated for moderate to severe adult periodontitis were monitored over a 12-month period for evidence of disease recurrence. Recurrent disease was detected at 32 sites in 18 subjects. Of these, 20 sites in 13 subjects were positive for W. recta. With subjects as the experimental unit, a significant increase in the proportions of W. recta was found at sites with recurrent disease (3.12%) as compared to stable, paired control sites (0.24%), but only when sites with breakdown and positive for W. recta were compared with their controls. These results indicate that W. recta is associated with some, but not all sites with advanced adult periodontitis. The association of W. recta with gingivitis was not statistically significant.

The ultrastructure of synchronized HeLa cells.

ABSTRACT Synchronous populations of mitotic HeLa cells were obtained by the controlled agitation method, and a detailed morphological study of the cells in all phases of the cell cycle was under-taken to correlate variations in cell structures to known coexisting biochemical events. Auto-radiographic techniques using tritiated thymidine (3H-TdR) were used to detect S1 cells, and colcemid was added to some G2 samples to prevent the cells from going into the next cycle, thus preventing contamination with G1 cells. The approximate duration (in hours) of the 4 phases were as follows: M = 1·4, G1= 8–9, S = 7, G2 = 4, and the generation time (T) = 21 ± 2 h. Randomization of the cell populations became apparent in the G2 phase (contaminated with S and M cells) and was most likely a result of the genetic make-up of the individual (mixoploid) HeLa cells, nutritional factors (serum lots used), temperature shock, and handling effects. Polyribosomes shifted to monomeric ribosomes during late prophase, at which time nucleoli also break down. These changes are correlated with the drop in protein and RNA synthesis reported for mitotic mammalian cells. The Golgi apparatus persisted in a modified form throughout mitosis. The mid-body forms from the anaphase stem-body and may interfere with the separation of daughter cells. Our studies suggest that the mid-body goes to one of the daughter cells where remnants of this structure were seen in early G1 cells. Large numbers of polyribosomes and the presence of well-developed nucleoli (many attached to the nuclear envelope) characterized G1. These structures, which play a major role in protein and RNA synthesis, persist with slight variations throughout inter-phase. Dense fibrillar nuclear bodies were prominent in late G1 cells. Centrioles separate during G1, and replicate by orthogonal budding during the S phase. Reproducible labelling patterns which reflect the asynchronous multireplicon nature of DNA synthesis in mammalian cells were characteristic of the various stages of the 51 phase. Granular nuclear bodies, which were prominent in S and G2 cells, may correspond to the larger species of heterogeneous nuclear RNA found in HeLa cells. G2 cells were similar in appearance to S cells. As heterochromatin areas increased in late G2 and prophase, perichromatin granules (of unknown significance) became prominent. Mitochondria behaved as independent cell organelles throughout the cell cycle. Hypertrophied RER, SER, and annulate lamellae, characterized the cytoplasm of colcemid-treated cells. The above changes are indicative of increased metabolic activity, and these structures may function in the production of colcemid-detoxifying enzymes in a manner analogous to that of drug-treated hepatocytes, such as those treated with phenobarbital.

Molar Absorptivity Values for Aflatoxins and Justification for Their Use as Criteria of Purity of Analytical Standards

Abstract Measurements of molar absorptivities in methanol were carried out by two laboratories on samples of anatoxins Bi and Gi prepared and purified independently in four laboratories and on samples of aflatoxins B2 and G2 prepared and purified independently in three laboratories. Molar absorptivities of pure aflatoxins Bi, B2, G1, and G2 in benzene-acetonitrile (98 + 2) were determined at two laboratories. With the exception of aflatoxin G2, no significant difference between aflatoxin samples could be demonstrated. Molar absorptivity values and absorbance ratios for each aflatoxin, based on these data, are given. Statistical 95% confidence limits were established for a single determination of molar absorptivity. A statistical study was made of the components of variance which contribute to the accuracy of the determination of molar absorptivity. A comparison of the fluorescence intensities of spots of various aflatoxin preparations, developed on silica gel-coated thin layer plates, with the amount of aflatoxin in each spotting solution as determined by absorbance measurements, demonstrated the validity of using absorbance and fluorescence comparison measurements for aflatoxin quantitation.