49 Collection of Day 7 equine embryos in aluteal cycles in mares

Serial administration of prostaglandin F2α (PGF2) in early diestrus has been recently shown to prevent luteal function in mares and is associated with delayed embryo development in induced aluteal cycles (progesterone deprived environment; <1.0ng mL−1; Leisinger et al. 2018 Theriogenology 105, 178-183). We hypothesised that embryos collected on Day 7 during induced aluteal cycles would be developmentally delayed compared with those collected from control cycles (progesterone deprived environment but supplemented with exogenous progestogen). Mares were monitored until a preovulatory follicle=35mm and the presence of uterine oedema were detected by ultrasonography. Mares were treated IV once with 2000IU of human chorionic gonadotropin and artificially inseminated every other day with total motile spermatozoa from one stallion of known fertility until ovulation. Mares were examined twice daily to determine the occurrence of ovulation. After ovulation, mares were randomly assigned to the control group (serial PGF2 treatment+long-acting altrenogest) or AL group (serial PGF2 treatment only). Using a protocol to induce aluteal cycles (Leisinger et al. 2018 Theriogenology 105, 178-183), mares in the AL group (n=7) were treated twice daily with 10mg of PGF2 (Lutalyse, dinoprost tromethamine, Zoetis, Florham Park, NJ, USA) IM on Days 0, 1, 2, and then once daily on Days 3 and 4. Mares in the control group (n=4) were treated with serial PGF2 treatment as mentioned before, and treated with a single injection of 225mg altrenogest (BioRelease Altrenogest LA 150; BET Pharm, Lexington, KY, USA) IM at the time of ovulation. On Day 7 post-ovulation, embryo collection was performed by uterine flushing using lactated Ringer’s solution. The developmental stage of embryos, diameter, and quality were determined using a stereomicroscope and photographed. Embryos were washed 3 times in commercial embryo holding medium (EmCare™ Holding Solution, ICP Bio, Spring Valley, WI) and stained with 1µg mL−1 of 4’,6-diamidino-2-phenylindole at 38.5°C for 15min to determine the number of nonviable cells. Data were analysed using t-test or Mann-Whitney U test where appropriate. Statistical significance was set at P=0.05. Data are reported as mean±s.e.M. Overall, the developmental stage of control embryos differed from AL embryos (P<0.03). In the control group, all embryos (n=4) collected were classified as expanded blastocysts. In contrast, embryos (n=7) collected from the AL group were all early blastocysts. Furthermore, the mean embryo diameter differed in control v. AL groups, 401±8mm v. 166±2mm, respectively (P<0.001). The quality grades of control embryos (1.3±0.3) were not different from the AL group (1.3±0.2; P>0.05). All embryos of both groups had less than 10% of blastomeres stained with 4’,6-diamidino-2-phenylindole. This study showed that morphologically normal equine embryos of acceptable quality can be collected on Day 7 in aluteal cycles.

165 In vitro maturation of ovine and caprine oocytes during breeding and nonbreeding seasons

The current study investigated the in vitro meiotic competence of ovine and caprine oocytes that underwent nuclear maturation during the breeding and nonbreeding seasons. We hypothesised that maturation rates of ovine and caprine oocyte would be significantly lower during the nonbreeding season. Ovine (Katahdin crossbred) and caprine (mainly Spanish crossbred) ovaries were collected from a local abattoir in the southern United States. Age of the animals was not determined. Cumulus-oocyte complexes (COC) were harvested by slicing the ovaries and searching using a stereomicroscope. Oocytes with more than 3 layers of unexpanded cumulus cells and with evenly granulated cytoplasm were selected for in vitro maturation (IVM). A commercial bovine IVM media (IVF Bioscience, Falmouth, United Kingdom) was used throughout the study. After 24h of IVM, ovine and caprine oocytes were denuded and oocytes with an extruded polar body (meiotic metaphase II oocytes) were considered to have reached nuclear maturation. The seasons in this study were defined as follows: breeding season=September to April and nonbreeding season=May to July. The presence of corpus hemorrhagicum or corpus luteum in at least 70% of the ovaries indicated the breeding season for the animals. Proportions of oocytes undergoing nuclear maturation were analysed using a two-tailed Chi-squared test. Statistical significance was set at P ≤ 0.05. The ovine maturation rate was 59% (65/111) and 49% (254/519) and the caprine maturation rate was 70% (39/56) and 40% (64/162) during the breeding and nonbreeding seasons, respectively. These results show a significant difference in nuclear maturation for caprine oocytes (P<0.001) during the breeding and nonbreeding seasons; however, there was no significant difference in nuclear maturation for ovine oocytes (P=0.06) during the breeding and nonbreeding seasons. High environmental temperatures during the nonbreeding season may have had detrimental effects on oocyte nuclear maturation in caprine but not in ovine oocytes. Why oocytes from these 2 species differ on how they are adversely affected by season remains to be elucidated.

The thyroid status reprograms T cell lymphoma growth and modulates immune cell frequencies

In spite of considerable evidence on the regulation of immunity by thyroid hormones, the impact of the thyroid status in tumor immunity is poorly understood. Here, we evaluated the antitumor immune responses evoked in mice with different thyroid status (euthyroid, hyperthyroid, and hypothyroid) that developed solid tumors or metastases after inoculation of syngeneic T lymphoma cells. Hyperthyroid mice showed increased tumor growth along with increased expression of cell cycle regulators compared to hypothyroid and control tumor-bearing mice. However, hypothyroid mice showed a higher frequency of metastases than the other groups. Hyperthyroid mice bearing tumors displayed a lower number of tumor-infiltrating T lymphocytes, lower percentage of functional IFN-γ-producing CD8(+) T cells, and higher percentage of CD19(+) B cells than euthyroid tumor-bearing mice. However, no differences were found in the distribution of lymphocyte subpopulations in tumor-draining lymph nodes (TDLNs) or spleens among different experimental groups. Interestingly, hypothyroid TDLN showed an increased percentage of regulatory T (Treg) cells, while hyperthyroid mice displayed increased number and activity of splenic NK cells, which frequency declined in spleens from hypothyroid mice. Moreover, a decreased number of splenic myeloid-derived suppressor cells (MDSCs) were found in tumor-bearing hyperthyroid mice as compared to hypothyroid or euthyroid mice. Additionally, hyperthyroid mice showed increased cytotoxic activity, which declined in hypothyroid mice. Thus, low levels of intratumoral cytotoxic activity would favor tumor local growth in hyperthyroid mice, while regional and systemic antitumor response may contribute to tumor dissemination in hypothyroid animals. Our results highlight the importance of monitoring the thyroid status in patients with T cell lymphomas.

KEY MESSAGES

T cell lymphoma phenotype is paradoxically influenced by thyroid status. Hyperthyroidism favors tumor growth and hypothyroidism rises tumor dissemination. Thyroid status affects the distribution of immune cell types in the tumor milieu. Thyroid status also modifies the nature of local and systemic immune responses.

Thyroid status modulates T lymphoma growth via cell cycle regulatory proteins and angiogenesis

We have shown in vitro that thyroid hormones (THs) regulate the balance between proliferation and apoptosis of T lymphoma cells. The effects of THs on tumor development have been studied, but the results are still controversial. Herein, we show the modulatory action of thyroid status on the in vivo growth of T lymphoma cells. For this purpose, euthyroid, hypothyroid, and hyperthyroid mice received inoculations of EL4 cells to allow the development of solid tumors. Tumors in the hyperthyroid animals exhibited a higher growth rate, as evidenced by the early appearance of palpable solid tumors and the increased tumor volume. These results are consistent with the rate of cell division determined by staining tumor cells with carboxyfluorescein succinimidyl ester. Additionally, hyperthyroid mice exhibited reduced survival. Hypothyroid mice did not differ significantly from the euthyroid controls with respect to these parameters. Additionally, only tumors from hyperthyroid animals had increased expression levels of proliferating cell nuclear antigen and active caspase 3. Differential expression of cell cycle regulatory proteins was also observed. The levels of cyclins D1 and D3 were augmented in the tumors of the hyperthyroid animals, whereas the cell cycle inhibitors p16/INK4A (CDKN2A) and p27/Kip1 (CDKN1B) and the tumor suppressor p53 (TRP53) were increased in hypothyroid mice. Intratumoral and peritumoral vasculogenesis was increased only in hyperthyroid mice. Therefore, we propose that the thyroid status modulates the in vivo growth of EL4 T lymphoma through the regulation of cyclin, cyclin-dependent kinase inhibitor, and tumor suppressor gene expression, as well as the stimulation of angiogenesis.

Endocannabinoids mediate hyposalivation induced by inflammogens in the submandibular glands and hypothalamus

OBJECTIVE

The aim of this study was to investigate the factors that could participate on salivary glands hypofunction during inflammation and the participation of endocannabinoids in hyposalivation induced by the presence of inflammogens in the submandibular gland (SMG) or in the brain.

DESIGN

Salivary secretion was assessed in the presence of inflammogens and/or the cannabinoid receptor antagonist AM251 in the SMG or in the brain of rats. At the end of the experiments, some systemic and glandular inflammatory markers were measured and histopathological analysis was performed.

RESULTS

The inhibitory effect observed 1h after lipopolysaccharide (LPS, 50μg/50μl) injection into the SMG (ig) was completely prevented by the injection of AM251 (5μg/50μl) by the same route (P<0.05). The LPS (ig)-induced increase in PGE2 content was not altered by AM251 (ig), while the glandular production of TNFα induced by the endotoxin (P<0.001) was partially blocked by it. Also, LPS injection produced no significant changes in the wet weight of the SMG neither damage to lipid membranes of its cells, nor significant microscopic changes in them, after hispopathological analysis, compared to controls. Finally, TNFα (100ng/5μl) injected intracerebro-ventricularly (icv) inhibited methacholine-induced salivary secretion evaluated 30min after (P<0.01), but the previous injection of AM251 (500ng/5μl, icv) prevented completely that effect.

CONCLUSION

We conclude that endocannabinoids mediate the hyposialia induced by inflammogens in the SMG and in the brain. The hypofunction would be due to changes on signalling pathway produced by inflammatory compounds since anatomical changes were not observed.

Radioprotective potential of histamine on rat small intestine and uterus

The aim of this study was to improve knowledge about histamine radioprotective potential investigating its effect on reducing ionising radiation-induced injury and genotoxic damage on the rat small intestine and uterus. Forty 10-week-old male and 40 female Sprague-Dawley rats were divided into 4 groups. Histamine and histamine-5Gy groups received a daily subcutaneous histamine injection (0.1 mg/kg) starting 24 h before irradiation. Histamine-5Gy and untreated-5Gy groups were irradiated with a dose of whole-body Cesium-137 irradiation. Three days after irradiation animals were sacrificed and tissues were removed, fixed, and stained with haematoxylin and eosin, and histological characteristics were evaluated. Proliferation, apoptosis and oxidative DNA markers were studied by immunohistochemistry, while micronucleus assay was performed to evaluate chromosomal damage. Histamine treatment reduced radiation-induced mucosal atrophy, oedema and vascular damage produced by ionising radiation, increasing the number of crypts per circumference (239 ± 12 vs 160 ± 10; P<0.01). This effect was associated with a reduction of radiation-induced intestinal crypts apoptosis. Additionally, histamine decreased the frequency of micronuclei formation and also significantly attenuated 8-OHdG immunoreactivity, a marker of DNA oxidative damage. Furthermore, radiation induced flattening of the endometrial surface, depletion of deep glands and reduced mitosis, effects that were completely blocked by histamine treatment. The expression of a proliferation marker in uterine luminal and glandular cells was markedly stimulated in histamine treated and irradiated rats. The obtained evidences indicate that histamine is a potential candidate as a safe radioprotective agent that might increase the therapeutic index of radiotherapy for intra-abdominal and pelvic cancers. However, its efficacy needs to be carefully investigated in prospective clinical trials.

Biological effects of brachytherapy using a (32)P-patch on the skin of Sencar mice

In recent years, specially designed patches containing beta emitters have been developed for contact brachytherapy of skin lesions. The aim of the present work was to evaluate the biological effects of the (32)P-patch on the skin of Sencar mice as a result of a brachytherapy treatment. For this purpose, a (32)P-patch was prepared with Chromic (32)P-phosphate and silicone and the classical model of two-stage skin carcinogenesis was reproduced in Sencar mice. Animals were divided in six groups. Four groups received the contact brachytherapy treatments using a scheme of a single session of 40 and 60Gy (SD40 and SD60) and a scheme of two sessions of 40 and 60Gy each (FD40 and FD60). The other two groups were used as controls of the single (CSD) and the fractionated (CFD) treatments. Radiation doses were estimated with equations derived from the MIRD DOSE scheme, and biologically effective doses (BED) were calculated according to equations derived from the linear-quadratic model. The endpoint to evaluate the treatments effects was tumor size after a follow-up period of 44 days. Finally, animals were sacrificed in order to get samples of all tumors for histological analysis and PCNA staining. Erythema, dermatitis and skin ulceration developed in almost all treated animals, but they gradually healed with regeneration of tissue during the follow-up period. Radiation effects on the skin of SD40, SD60, FD40 and FD60 showed a significant reduction of the tumor size with regard to controls, independently of the scheme and the radiation dose considered. PCNA staining scores of control groups were higher than for treated groups, independently of the scheme and the radiation dose considered. This radioactive (32)P-silicone-patch which is easy to prepare and use in the treatment of skin diseases, seems promising as a radioactive device for clinical use.

Fetal and neonatal habituation in infants of diabetic mothers

OBJECTIVE

To evaluate whether maternal diabetes alters the habituation ability of fetuses and newborns.

STUDY DESIGN

Two nonrandomized clinical trials were performed. First, we studied prenatal fetuses of women with pregestational diabetes, and control subjects matched for gestational age, and then we studied infants of diabetic mothers (IDM) and control subjects matched for gestational age and mode of delivery. Fetus and newborns were stimulated with vibroacoustic stimulus.

RESULTS

In fetuses of diabetic mothers, the ability to habituate was lower, and the habituation rate was higher than in control subjects to all habituation tests. In the neonatal period, ability to habituate was lower (59% vs 100%; P< .001), and the habituation rate was higher (18 [14-21] vs 4 [1.2-6.8]; P< .001) in the IDM than in the control infants. We found a significant negative correlation between maternal glycosylated hemoglobin in each trimester of pregnancy and habituation ability in IDM.

CONCLUSIONS

Fetuses and infants of diabetic mothers have impaired habituation ability, which is related to the degree of maternal metabolic control.

Latin American Brain Mapping Network (LABMAN)

On March 8, 2008 in Havana, the Latin American Network for Brain Mapping (LABMAN) was created with participants from Argentina, Brazil, Colombia, Cuba and Mexico. The focus of LABMAN is to promote neuroimaging and systems neuroscience in the region through the implementation of training and exchange programs, and to increase public awareness of the Latin American potential to contribute both to basic and applied research in human brain mapping.

Stem cell markers in gastrointestinal cancer

21095

Background: Cancer cells with stem cells (CSC) properties have been identified in different tumors. It is suggested that CSC are responsible for the continuous growth of tumors, metastasis and drug-resistance. Markers for stem cells have been described. Oct4 and Nanog are transcription factors required to maintain the pluripotency and self-renewal of embryonic stem (ES) cells. ABCG2 transporter (MDR1) gene expression has been described as surrogate for the side-population phenotype. PTTG1 has also been recently identified as a component of the molecular signature of human (hu) ES cell-lines. Methods: Using Digital Northern we have demonstrated a significant tag counts for PTTG1 and reticulocalbin 2 (RCN2) in 11 huES cell-lines of the CGAP. The objective of our work has been to assess gene expression of these SC markers in a panel of new gastrointestinal cancer (GC) cells lines (CL) developed in our laboratory. Quantitative assessment was obtained by real-time PCR relative to normal bone marrow (BM), colonic mucosa and established cell-lines. GCCLs have been developed from ascitic fluid obtained of pancreatic carcinoma (MBQ-OJC1) and colon cancer (JJPF-OJC4, LCM-OJC5 and JAC-OJC6). GCCLs had been fully characterized by cytomorphology, epithelial and tumor markers (keratins, EGFR, EpCAM, p53), karyotype and tumor spheroids cultures. Results: Expression for ABCG2, Nanog, Oct4, PTTG1 and RCN2 were clearly detected in all the GCCL. Relative levels for each mRNA shown wide variety. For example, ABCG2 mRNA was highly expressed (2–26 fold) in colon cancer CL relative to BM. RCN2 was overexpressed (more than 2 x 102 fold) in 3 GCCL. Conclusions: Our results show that expressions of different “stemness” genes are maintained in cultured cancer cells. These data suggest that CSC are present in metastatic sites and can be maintained in continuous culture. We hypothesized that PTTG1 and RCN2 could be tested as a new cancer stem cells markers.

No significant financial relationships to disclose.

Texture-based echocardiographic segmentation using a non-parametric estimator and an active contour model

An accurate segmentation of cardiac cavities is necessary to assess cardiac function and to determine quantitative parameters. Several semi-automatic techniques have been tested to achieve this goal. In this work we propose an algorithm to segment cardiac structures, based on a robust pre-processing step that eliminates noise and extracts an initial frontier, together with a refined deformable model, that integrates edge confidence and texture information. Results show that a combination of a mean-shift filter with an active contour model is adequate for echographic images, especially when texture information is included.

Synovial chondromatosis of the temporomandibular joint: CT and MRI findings

We report a rare case of synovial chondromatosis of the temporomandibular joint (TMJ) in a 31-year-old man. CT examination showed a mixed soft tissue mass with small calcifications near the right TMJ joint space. MR images revealed a heterogeneous mass on the different sequences and, after contrast administration, originating in the right TMJ. Cytology showed chondroid cellularity. The lesion was surgically removed and final histological study demonstrated the diagnosis of a synovial chondromatosis. We highlight the importance of the complementary findings from CT and MR, especially the important specific feature described for TMJ synovial chondromatosis related to the mixed density within the mass, in order to perform an accurate preoperative diagnosis whenever there is an absence of ossified loose bodies.

Molecular and immunologycal basis of a novel therapeutic formulation: Oligoelements Zn, Se and Mn plus Lachesis Muta venom (O-LM)

13158

Background: We have previously reported that O-LM inhibited malignant cell proliferation in vitro and in vivo, increasing survival in rodent tumor models. We also demonstrated a protective action of O-LM against undesirable effects of chemotherapy and ionizing radiation, enhancing their therapeutic action. Furthermore, O-LM applied to patients with advanced breast, colon and pancreatic cancer resulted in increased survival and better quality of life with no side effects. In this work we further investigated the mechanisms involved in O-LM therapeutic effect. Methods: Two groups of Nude mice, control and O-LM (Zn, Se, Mn 4μ g/ml each; L. Muta 4 ng/ml) treated (0.1 ml/day, sc) were inoculated with PANC-1 cells to evaluate tumor development. PCNA, P53, antioxidant enzymes, apoptosis, microvessels and immune cell markers were studied by immunohistochemistry. In control and O-LM treated BALB/c mice we determined in vitro responses to T and B selective mitogens. Results: O-LM treated tumors showed significant lower growing rate, smaller mass (3,77±0,95 vs 9,75±2,30 cm3) and an important peritumoral lymphoid infiltrate. Apoptotic cells and P53 expression were increased while PCNA was negative and microvessels counts were lower than controls. O-LM produced a 3-fold increase in Superoxide Dismutase activity. The infiltrates showed an important number of CD11 bearing cells and B220 positive but CD3 and CD19 negative cells, suggesting the presence of NK cells. In BALB/c mice T selective mitogen Con A, but not B selective mitogens responses were enhanced, with a maximum after 60 days of O-LM treatment. A 4-fold increase in IFNγ release was observed in cell-free supernatants from lymph node culture stimulated with Con A obtained from 60-days treated mice. Conclusions: Present data demonstrate the capacity of O-LM to modulate free radical production, the expression of tumor markers and suggest an important up-regulation of innate and T-cell mediated immunity induced by in vivo treatment with O-LM. These results reinforce the hypothesis that the effective therapeutic action of O-LM is based on its ability of targeting simultaneously multiple pathways involved in cancer development with the additional advantage of the total absence of adverse effects.

No significant financial relationships to disclose.

Ultramicroscopic and biochemical changes in ram spermatozoa cryopreserved with trehalose-based hypertonic extenders

The ability of a range of extenders to cryopreserve ram spermatozoa was tested. The extenders were modified by the inclusion of citrate, Tris buffer, trehalose, and EDTA. Ejaculates from three Pampinta rams were evaluated and pooled at 30 degrees C. The semen was diluted to contain 1 x 10(9) cells/mL, cooled to 5 degrees C, loaded into 0.25-mL straws, frozen and stored in liquid nitrogen. Evaluation was based on the hypoosmotic swelling test (HOS test), electron microscopy, and biochemical parameters such as lipid peroxidation and reduced and total glutathione levels, all measured after thawing. The HOS test indicated that the percentage of intact plasma membranes after freezing and thawing was significantly higher for the hypertonic extender containing trehalose (T), compared with an extender containing trehalose+EDTA (TE) or an isotonic Tris extender (B) (p < 0.05). Membrane evaluation by ultramicroscopy also indicated better sperm cryopreservation in extender T compared with the others, and there was a significant reduction in the number of damaged membranes (27%, p < 0.0002). The level of reduced glutathione was significantly higher after sperm cryopreservation in either hypertonic diluent (T and TE) with respect to the isotonic extender B, immediately after thawing (12%) and after a 3-h post-thawing thermotolerance test at 37 degrees C (17%, p = 0.007). Total glutathione levels did not show statistical differences among the extenders. After 3h post-thawing incubation at 37 degrees C, lipid peroxide levels in spermatozoa were statistically lower for T than TE (35%) or isotonic extender B (44%) (p = 0.002). Taken together these results indicate a reduction in the oxidative stress provoked by freezing and thawing when semen is cryopreserved in extender T. The antioxidant properties of extender T may be related to its effectiveness in membrane cryopreservation.

The Lettuce infectious yellows virus (LIYV)-encoded P26 is associated with plasmalemma deposits within LIYV-infected cells

Cytological, immunological, and mutagenesis approaches were used to identify the viral factors associated with the formation of plasmalemma deposits (PLDs) in whole plants and protoplasts infected by Lettuce infectious yellows virus (LIYV). Transmission electron microscopy and immunogold labeling using polyclonal antibodies to four of the five LIYV RNA 2-encoded large proteins, capsid protein (CP), minor capsid protein (CPm), HSP70 homolog (HSP70h), and P59, showed specific labeling of LIYV virions or virion aggregates around the vesiculated membranous inclusions, but not PLDs in LIYV-infected Nicotiana benthamiana, Nicotiana clevelandii, Lactuca sativa, and Chenopodium murale plants, and Nicotiana tabacum protoplasts. In contrast, antibodies to the RNA 2-encoded P26 showed specific labeling of PLDs but not virions in both LIYV-infected plants and protoplasts. Virion-like particles (VLPs) were seen in protoplasts infected by all LIYV RNA 2 mutants except for the CP (major capsid protein) mutant. PLDs were more difficult to find in protoplasts, but were seen in protoplasts infected by the CP and CPm mutants, but not in protoplasts infected by the P26, HSP70h, or P59 mutants. Interestingly, although the CPm mutant showed VLPs and PLDs, the PLDs did not show associated virions/virion-like particles as was always observed for PLDs seen in protoplasts infected by wild-type LIYV. Immunoblot analyses performed on purified LIYV virions showed that P26 was not detected with purified virions, but was detected in the cell wall, 1000 g and 30,000 g pellet fractions of LIYV-infected plants. These data suggest that P26 is associated with the LIYV-induced PLDs, and in contrast to the other RNA 2-encoded large proteins, P26 is not a virion protein.

Primary biliary tract malignant melanoma: US, CT, and MR findings

We report a case of primary biliary tract malignant melanoma occurring in a 47-year-old male. Ultrasonography and computed tomography showed multiple masses in the gallbladder and distal common bile duct that caused biliary tract dilatation. Magnetic resonance imaging showed that the polypoid masses in the gallbladder and common bile duct were of low signal intensity on T2-weighted images and of high signal intensity on unenhanced T1-weighted images.

Analysis and localization of epileptic events using wavelet packets

This article compares results obtained in previous studies using time-frequency representations (Wigner-Ville, Choi-Williams and Parametric) and the wavelet transform with those obtained with wavelet packet functions to show new findings about their quality in the analysis of ECoG recordings in human intractable epilepsy: data from 21 patients have been analyzed and processed with four types of wavelet functions, including Orthogonal, Biorthogonal and Non-Orthogonal basis. These functions were compared in order to test their quality to represent spikes in the ECoG. The energy based on the wavelet coefficients to different scales was also calculated. The best results were found with the biorthogonal-6.8 wavelet on 5-7 scales, which gave 0.92 sensitivity, but with a high percentage of false positives; this representation was highly correlated with spike events on time and duration. To improve these results we have studied the wavelet packet coefficients energy. We found that reconstruction wavelet packet coefficients at 4 and 9 nodes contain significant information to characterize the spike event. These nodes' reconstruction coefficients were multiplied and this product was highly correlated with spikes events on time and duration. With this procedure we improved the sensitivity up to 0.96 with the same biorthogonal-6.8 wavelet at four levels. With this technique we do not sacrifice computation time: 896 samples are processed at only 0.16 s, so that it is possible to show the spike scattering path on line, because 896 samples (7 s)/16 channels are processed at 3.13 s.

Green fluorescent protein expression from recombinant lettuce infectious yellows virus-defective RNAs originating from RNA 2

Lettuce infectious yellows virus (LIYV) RNA 2 defective RNAs (D RNAs) were compared in protoplasts for their ability to replicate and to express the green fluorescent protein (GFP) from recombinant D RNA constructs. Initially four LIYV D RNAs of different genetic composition were compared, but only two (LIYV D RNA M5 and M18) replicated to high levels. Both of these contained at least two complete ORFs, one being the 3'-terminal ORF encoding P26. Northern hybridization analysis using probes corresponding to 3' regions of LIYV RNA 2 detected the P26 subgenomic RNA from protoplasts infected with LIYV RNAs 1 and 2 or protoplasts inoculated only with RNA 1 plus either the LIYV D RNA M5 or M18, suggesting that these LIYV D RNAs served as templates to generate the P26 subgenomic RNA. The GFP coding region was inserted as an in-frame insertion into the P26 coding region of the LIYV M5 and M18 D RNAs, yielding M5gfp and M18gfp. When transcripts of M5gfp and M18gfp were used to inoculate protoplasts, bright fluorescence was seen only when they were co-inoculated with LIYV RNA 1. The percentage of fluorescent protoplasts ranged from experiment to experiment, but was as high as 5.8%. Time course analyses showed that fluorescence was not detected before 48 h pi, and this correlated with the timing of LIYV RNA 2 and RNA 2 D RNA accumulation, but not with that of LIYV RNA 1.

Effect of antioxidants on preservation of motility,viability and acrosomal integrity of equine spermatozoa during storage at 5 degrees C

Preservation of liquid semen at 5 degrees C is an important technique in the breeding management of horses. Oxidative damage to spermatozoa during storage is a potential cause of the decline in motility and fertility during hypothermic storage of liquid semen. The objective of this study was to evaluate the use of water-soluble and lipid-soluble antioxidants to improve the maintenance of motility of equine spermatozoa at 5 degrees C during storage for 72 to 96 h. In Experiment 1, the effect of addition of catalase on the maintenance of motility, viability and acrosomal integrity was determined. Semen was collected, and these treatments were applied: catalase (0, 100 or 200 U/mL) in nonfat, dried skim milk extender (NFDSM; with or without seminal plasma) or 10% seminal plasma + NFDSM. Motility was determined by computerized semen analysis (CASA) at 0, 24, 48 and 72 h. Viability and acrosomal integrity were determined at 72 h of storage. There was no significant treatment effect on the maintenance of sperm motility during 72 h storage. In Experiment 2, the effect of adding lipid-soluble antioxidants on maintenance of motility was evaluated. Semen was diluted to a final concentration of 25 x 10(6) sperm/mL in NFDSM containing butylated hydroxytoluene (BHT; 2.0, 1.0, or 0.5 mM), Vitamin E (4.0, 2.0, 1.0 mM), or Tempo (2.0, 1.0, or 0.5 mM). Although the addition of BHT significantly reduced (P < 0.05) progressive motility during storage compared to the control, there were no positive treatment effects of either Vitamin E or Tempo on maintenance of motility. In Experiment 3, the effect of adding water-soluble antioxidants on maintenance of motility was evaluated. Semen was diluted in NFDSM containing these treatments: Trolox (2.0 mM), Tempo (1.0 mM), Vitamin C (0.45 mg/mL), BSA (3% w/v), combinations of these antioxidants, or control. Adding these water-soluble antioxidants did not significantly improve the maintenance of motility during cooled storage at 5 degrees C. In conclusion, adding the enzyme scavenger, catalase, or a variety of lipid- and water-soluble antioxidants did not significantly improve the maintenance of motility during liquid semen storage at 5 degrees C.

Effect of bonding variables on the shear bond strength and interfacial morphology of a one-bottle adhesive

This study's objectives were: 1) to determine the combination of bonding procedures (with or without acid etching, moist or dry substrate, one or two applications of primer/adhesive) that would produce the highest shear bond strength of Prime & Bond and Dyract AP and 2) to characterize the resin-dentin/enamel interface produced by these bonding procedures. Ninety-six bovine incisors were randomly assigned to eight groups for shear bond testing to enamel (n = 6) and dentin (n = 6). Prime & Bond and Dyract AP were applied and cured following manufacturers' instructions. Shear bond testing was conducted in a Universal Testing Machine. Thirty-two bovine incisors were sectioned to produce blocks with enamel and dentin, then bonded in pairs for evaluation of interfacial morphology. They were polished and argon ion-etched using a high-speed argon ion-etching machine and examined by SEM. The groups where enamel was etched, kept moist or dry and received a single application of Prime & Bond produced the highest shear bond strength. Dentin bond strengths were high in the groups where dentin was etched and kept moist. The number of Prime & Bond applications had no effect on dentin bond strength. Acid etching results in better adaptation of Prime & Bond to enamel and dentin regardless of whether moisture is present.

Electrogenic Na(+)-dependent L-alanine transport in the lizard duodenum. Involvement of systems A and ASC

L-Alanine transport across the isolated duodenal mucosa of the lizard Gallotia galloti has been studied in Ussing chambers under short-circuit conditions. Net L-alanine fluxes, transepithelial potential difference (PD), and short-circuit current (Isc) showed concentration-dependent relationships. Na(+)-dependent L-alanine transport was substantially inhibited by the analog alpha-methyl aminoisobutyric acid (MeAIB). Likewise, MeAIB fluxes were completely inhibited by L-alanine, indicating the presence of system A for neutral amino acid transport. System A transport activity was electrogenic and exhibited hyperbolic relationships for net MeAIB fluxes, PD, and Isc, which displayed similar apparent K(m) values. Na(+)-dependent L-alanine transport, but not MeAIB transport, was partially inhibited by L-serine and L-cysteine, indicating the participation of system ASC. This transport activity represents the major pathway for L-alanine absorption and seemed to operate in an electroneutral mode with a negligible contribution to the L-alanine-induced electrogenicity. It is concluded from the present study that the active Na(+)-dependent L-alanine transport across the isolated duodenal mucosa of Gallotia galloti results from the independent activity of systems A and ASC for neutral amino acid transport.

Newly-developed diamond points for conservative operative procedures

The rapid decrease in the size of dental restorations has increased the demand for the smallest rotary cutting instrument possible. The width of cavities prepared with two experimental diamond points and the smallest commercial diamond point were compared and significant differences found. SEM observation of the head surfaces of the three diamond points revealed that the experimental points had comparable cutting characteristics with the commercial diamond point.

The effect of reactive oxygen species on equine sperm motility, viability, acrosomal integrity, mitochondrial membrane potential, and membrane lipid peroxidation

The objective of this study was to examine the influence of reactive oxygen species (ROS), generated through the use of the xanthine (X)-xanthine oxidase (XO) system, on equine sperm motility, viability, acrosomal integrity, mitochondrial membrane potential, and membrane lipid peroxidation. Equine spermatozoa were separated from seminal plasma on a discontinuous Percoll gradient, and spermatozoa were incubated with 0.6 mM X and 0.05 U/mL XO for 30 minutes. Catalase (150 U/mL), superoxide dismutase (SOD, 150 U/mL), or glutathione (GSH, 1.5 mM) were evaluated for their ability to preserve sperm function in the presence of the induced oxidative stress. At the end of the 30-minute incubation, sperm motility was determined by computer-assisted semen analysis. Viability and acrosomal integrity were determined by Hoechst-Pisum sativum staining, and mitochondrial membrane potential was determined by staining with JC-1. Incubation with the X-XO system led to a significant (P < .01) increase in hydrogen peroxide production and an associated decrease (P < .01) in motility parameters. Total motility was significantly (P < .01) lower in the presence of X-XO compared with the case of the control (29%+/-9% vs 73%+/-1%, respectively). Catalase, but not SOD, prevented a decline in motility secondary to oxidative stress (71%+/-4% vs 30%+/-3%, respectively). The addition of glutathione had an intermediate effect in preserving sperm motility at the end of the 30-minute incubation (53%+/-3%). No influence of X-XO could be determined on viability, acrosomal integrity, or mitochondrial membrane potential. In order to promote lipid peroxidation, samples were incubated with ferrous sulfate (0.64 mM) and sodium ascorbate (20 mM) for 2 hours after the X-XO incubation. No increase in membrane lipid peroxidation was detected. This study indicates that hydrogen peroxide is the major ROS responsible for damage to equine spermatozoa. The decrease in sperm motility associated with ROS occurs in the absence of any detectable decrease in viability, acrosomal integrity, or mitochondrial membrane potential or of any detectable increase in lipid peroxidation.

Membrane mechanisms for electrogenic Na(+)-independent L-alanine transport in the lizard duodenal mucosa

The active Na(+)-independent transport of L-alanine across the duodenal mucosa of the lizard Gallotia galloti was studied in Ussing-type chambers using a computer-controlled voltage clamp. Addition of L-alanine to the Na(+)-free bathing solutions resulted in a significant L-alanine absorption (J(net)) that was paralleled by an increase in transepithelial short-circuit current (I(sc)) and potential difference (PD) without apparent changes in the tissue conductance. The concentration dependence of J(net), PD, and I(sc) displayed Michaelis-Menten kinetics. L-alanine-induced electrical changes were completely inhibited by external alkaline pH or by the H(+)-ionophore carbonyl cyanide m-chlorophenyl-hydrazone in the bathing solution. The alanine-induced electrogenicity was dependent on the presence of extracellular K(+) and could be blocked by serosal Ba(2+) or mucosal orthovanadate. These results suggest the existence of an H(+)-coupled L-alanine cotransport at the apical membrane of enterocytes. The favorable H(+) driving force is likely to be maintained by an apical vanadate-sensitive H(+)-K(+)-ATPase, allowing the extrusion of H(+) in an exchange with K(+). Potassium exit through a basolateral barium-sensitive conductance provides the key step for the electrogenicity of L-alanine absorption.

Catalase activity in equine semen

OBJECTIVE

To characterize the activity of catalase in equine semen.

ANIMALS

15 stallions of known and unknown reproductive history.

PROCEDURE

Seminal plasma was collected from raw equine semen by centrifugation, and samples of seminal plasma were frozen prior to assay for catalase activity. Tissue samples (n = 3 stallions) from the bulbourethral gland, prostate gland, vesicular gland, and testis were homogenized, and cauda epididymal fluid was collected for determination of catalase activity. Catalase activity was determined as an enzyme kinetic assay by the disappearance of H2O2 as measured by ultraviolet spectrophotometry.

RESULTS

Catalase activity in equine seminal plasma was 989.3 +/- 1678 U/ml (mean +/- SEM), and the specific activity of catalase in equine seminal plasma was 98.7 +/- 29.2 U/mg of protein. Specific activity of catalase in tissue homogenates was significantly higher in the prostate gland (954 +/- 270 U/mg of protein) than in the ampulla (59 +/- 5 U/mg of protein), bulbourethral gland (54 +/- 11 U/mg of protein), vesicular gland (39 +/- 3 U/mg of protein), cauda epididymal fluid (11 +/- 3 U/mg protein), or testis (54 +/- 6 U/mg of protein).

CONCLUSIONS AND CLINICAL RELEVANCE

Equine seminal plasma contains a high activity of catalase that is derived primarily from prostatic secretions. Procedures such as semen cryopreservation that remove most seminal plasma from semen may reduce the ability to scavenge H2O2 and thereby increase the susceptibility of spermatozoa to oxidative stress.

Time-frequency analysis of the heart rate variability during the Valsalva manoeuvre

We present an analysis of the heart rate variability during the Valsalva manoeuvre. The more frequently used time-frequency distributions were applied in order to analyse the dynamical behaviour of several spectral indexes during the manoeuvre. The influence of the branches of the autonomous system can be predicted following the evolution of the studied indexes. The exponential time-frequency distribution showed the best results in the graphical representation, as well as in the indexes calculation. The total power, the low-to-high frequency ratio and the fractal dimension were analysed throughout the different phases of the manoeuvre and a representative model of these parameters' evolution was proposed.

Subcellular localization of the HSP70-homolog encoded by beet yellows closterovirus

Closteroviridae is the only viral family coding for a homolog of HSP70 (HSP70h). Polyclonal antiserum to recombinant beet yellows closterovirus (BYV) HSP70h was generated and used for immunogold labeling of the leaf samples derived from the infected Nicotiana benthamiana plants. Ultrastructural analysis revealed the preferential accumulation of BYV in phloem, although occasional infection of the leaf mesophyll cells was also observed. The strongest HSP70h-specific labeling was associated with virion aggregates and vesicles harboring scattered virions. HSP70h was also observed in close proximity of plasmodesmata and inside the plasmodesmatal channels. The possible role of the BYV HSP70h in RNA encapsidation was tested in tobacco protoplasts. A BYV mutant possessing an inactivated HSP70h gene exhibited no detectable encapsidation defects. Collectively, the obtained results suggested that closteroviral HSP70h escorts the virions to their destinations inside the infected cells and possibly participates in the intercellular translocation of BYV.

Robust retrieval of three-dimensional structures from image stacks

Robust high-breakdown-point location estimators are employed to analyze image stacks under the piecewise constant image structure model. To reduce the effect of bias along the Z-axis, the class parameters are extracted using three consecutive slices, The segmentation algorithm first determines the most reliable seed regions, which are then used in a region-growing procedure supported by local evidence. The robustness and stability of the proposed technique is shown with both synthetic and real data, the latter consisting of one MRI and one confocal microscopy set. The performance of the algorithm is consistent with the ground truth obtained with manual segmentation by physicians.

Specific inclusion bodies are associated with replication of lettuce infectious yellows virus RNAs in Nicotiana benthamiana protoplasts

Nicotiana benthamiana mesophyll protoplasts, either mock-inoculated or inoculated using in vitro transcripts derived from lettuce infectious yellows virus (LIYV) RNA 1- and/or RNA 2-cloned cDNAs were analysed by transmission electron microscopy (TEM) and, in some cases, also by immunogold labelling. TEM revealed the main cytopathological effects of LIYV infections in N. benthamiana protoplasts infected with RNAs 1 and 2: (a) typical closterovirus-induced (beet yellows virus-type) accumulations of vesiculated cytoplasmic membranes as inclusion bodies, sometimes with associated virions; (b) scattered aggregations of virions within the cytoplasm; and (c) electron-dense plasmalemma deposits. These were not seen in mock-inoculated protoplasts. Protoplasts inoculated only with LIYV RNA 1 contained vesiculated cytoplasmic inclusion bodies, but not virions or plasmalemma deposits. Thus, infection by only LIYV RNA 1 is sufficient to induce characteristic closterovirus vesiculated cytoplasmic inclusion bodies. However, both LIYV RNAs 1 and 2 are needed for production of virions and plasmalemma deposits.

Comparison of the heart rate variability parameters obtained from the electrocardiogram and the blood pressure wave

Four temporal and four spectral parameters of heart rate variability were compared after they were computed with two different time series generation methods: the RR intervals and the numerical values of heart rate provided by the Finapres. Recordings were obtained from 10 healthy subjects throughout five experimental conditions: supine, standing, controlled breathing, exercise and recovery. The mean and the RMS value of successive differences showed significant differences between the two methods. The spectral parameters were statistically different only during standing and exercise. The larger high frequency component and the lower HF/LF ratio by the Finapres method, observed during exercise, can be explained by the higher breathing influence on the peak-to-peak pressure intervals, in relation to RR intervals. Therefore, the high frequency component within mechanic intervals could possibly reflect the non-neural respiratory influence. In conclusion, values of heart rate provided by the Finapres are not completely interchangeable with those obtained from the ECG during the studied conditions.

Sodium butyrate inhibits carcinoma development in a 1,2-dimethylhydrazine-induced rat colon cancer

BACKGROUND

Butyric acid is one of the most important by-products of dietary fiber degradation. It is an important trophic agent for the intestinal mucosa under different experimental conditions. Data obtained from several in vitro studies strongly suggest that butyrate can be a potential therapeutic agent in controlling the growth of some cancer cells. However to date in vivo animal studies have failed to show conclusive results.

METHODS

We evaluated the effects of intracecal administration of butyrate in an experimental model of colonic carcinogenesis induced by 1,2-dimethylhydrazine (DMH), administered at the site where it is naturally produced, the cecum. We studied the incidence of colon tumors and their main histologic features.

RESULTS

Direct application of sodium butyrate significantly decreased the total number of tumors and the incidence of malignancies and carcinoma in the colon.

CONCLUSIONS

Butyrate may inhibit the growth of tumors induced by DMH.

Induction of caspase-3 protease activity and apoptosis by butyrate and trichostatin A (inhibitors of histone deacetylase): dependence on protein synthesis and synergy with a mitochondrial/cytochrome c-dependent pathway

The induction of apoptosis of tumor cells by the colonic fermentation product butyrate is thought to be an important mechanism in protection against colorectal cancer. Because a major action of butyrate is to inhibit histone deacetylase (leading to chromatin relaxation and altered gene expression), butyrate may induce apoptosis by derepression of specific cell death genes. Here we show that butyrate and trichostatin A (a more selective inhibitor of histone deacetylase) induce the same program of apoptosis in Jurkat lymphoid and LIM 1215 colorectal cancer cell lines that is strictly dependent on new protein synthesis (within 10 h) and that leads to the conversion of the proenzyme form of caspase-3 to the catalytically active effector protease (within 16 h) and apoptotic death (within 24 h). Cells primed with a low concentration of butyrate that itself did not induce activation of caspase-3 or apoptosis were, nevertheless, rendered highly susceptible to induction of apoptosis by staurosporine (an agent that has recently been shown to act by causing mitochondrial release of cytochrome c). Synergy between butyrate and staurosporine was due to the presence of a factor in the cytosol of butyrate-primed cells which enhanced over 7-fold the activation of caspase-3 induced by the addition of cytochrome c and dATP to isolated cytosol. We propose that changes at the level of chromatin structure, induced by a physiological substance butyrate, lead to the expression of a protein that facilitates the pathway by which mitochondria activate caspase-3 and trigger apoptotic death of lymphoid and colorectal cancer cells.

[Jejuno-ileal volvulus, a rare cause of intestinal obstruction]

Volvulus of the small bowel without predisposing anatomical defects is a rare cause of acute intestinal obstruction in the Western world, and its incidence is decreasing in Europe and America, although it is common in others parts of the world. The causes of primary volvulus of the small bowel and the mechanism of rotation of the entire root of the mesentery remain unexplained. Several anatomical and dietary factors have been implicated. This theory requires strong peristalsis, tense, firm abdominal muscles and feeding pattern of very bulky meals taken at long intervals. In the present case, a large quantity of bulky poorly digested food consumed previously, and strong abdominal muscles are in keeping with the above theory.

Beet western yellows luteovirus capsid proteins produced by recombinant baculoviruses assemble into virion-like particles in cells and larvae of Bombyx mori

We subcloned various constructs of the beet western yellows luteovirus (BWYV) 3' proximal genes into Bombyx mori nuclear polyhedrosis virus (BmNPV) transfer vectors and constructed recombinant BmNPVs. The recombinant BmNPVs were used to infect BmN cells and B. mori larvae. Protein expression was analyzed by SDS-PAGE and immunoblot analysis, and the BWYV-encoded capsid protein (CP), P19, readthrough protein (RT), and a modified capsid-readthrough protein (CP-RT*) were detected in BmN cells infected by the respective BmNPVs. However, we detected only the BWYV CP and P19 in BmN cells infected with a recombinant BmNPV containing all three BWYV 3' proximal genes. BmN cells and fat body cells from B. mori larvae infected with recombinant BmNPVs were analyzed by transmission electron microscopy and immunogold labeling. Particles which morphologically and serologically resembled BWYV virions were detected in the nuclei of BmN cells and B. mori larval fat body cells infected with recombinant BmNPVs producing either the BWYV CP alone or BWYV CP plus a BWYV CP-RT*. Similar particles were not detected in cells infected with a control BmNPV or recombinant BmNPV producing only CP-RT*.