Dengue virus identification by transmission electron microscopy and molecular methods in fatal dengue hemorrhagic fever

Dengue virus is the most significant virus transmitted by arthropods worldwide and may cause a potentially fatal systemic disease named dengue hemorrhagic fever. In this work, dengue virus serotype 4 was detected in the tissues of one fatal dengue hemorrhagic fever case using electron immunomicroscopy and molecular methods. This is the first report of dengue virus polypeptides findings by electron immunomicroscopy in human samples. In addition, not-previously-documented virus-like particles visualized in spleen, hepatic, brain, and pulmonary tissues from a dengue case are discussed.

Effect of several antioxidants on thawed ram spermatozoa submitted to 37°C up to four hours

Thawed ram spermatozoa were incubated at 37°C in the presence of dehydroascorbic acid (DHA), TEMPOL (TPL), N-acetyl-cysteine (NAC) and rutin (RUT), at 0.1 and 1 mm, in order to test their effects on sperm physiology. Cryopreserved spermatozoa from four rams were thawed, pooled, washed and incubated in TALP-Hepes with 1 mm or 0.1 mm of each antioxidant, performing a replicate with induced oxidative stress (Fe(2+) /ascorbate). Motility (CASA), viability and mitochondrial membrane potential (flow cytometry) were analysed at 2 and 4 h. Lipoperoxidation (MDA production), intracellular reactive oxygen species (ROS) and DNA status (TUNEL) were analysed at 4 h. Antioxidants, except DHA 0.1 mm, decreased motility and kinematic parameters, but had little effect on viability or mitochondrial activity. Except 1 mm DHA, the antioxidants reduced ROS at 4 h. Moreover, NAC 1 mm, rutin and TEMPOL reduced ROS and DNA damage in the presence of oxidative stress. N-acetyl-cysteine, rutin 1 mm and TEMPOL reduced lipoperoxidation in the presence of oxidative stress. However, DHA did not affect lipoperoxidation. At 1 mm, DHA increased DNA damage in the absence of oxidative stress. Dehydroascorbic acid effects could arise from spermatozoa having a low capacity for reducing it to ascorbic acid, and it may be tested in the presence of other antioxidants or reducing power. Future research should focus in testing whether the inhibition of motility observed for NAC, rutin and TEMPOL is reversible. These antioxidants might be useful at lower temperatures (refrigerated storage or cryopreservation) when their protective effects could be advantageous.

Inherent growth hormone resistance in the skeletal muscle of the fine flounder is modulated by nutritional status and is characterized by high contents of truncated GHR, impairment in the JAK2/STAT5 signaling pathway, and low IGF-I expression

A detailed understanding of how the GH and IGF-I regulate muscle growth, especially in early vertebrates, is still lacking. The fine flounder is a flatfish species exhibiting remarkably slow growth, representing an intriguing model for elucidating growth regulatory mechanisms. Key components of the GH system were examined in groups of fish during periods of feeding, fasting, and refeeding. Under feeding conditions, there is an inherent systemic and local (muscle) GH resistance, characterized by higher levels of plasma GH than of IGF-I, skeletal muscle with a greater content of the truncated GH receptor (GHRt) than of full-length GHR (GHRfl), an impaired activation of the Janus kinase 2 (JAK2)-signal transducers and activators of transcription 5 (STAT5) signaling pathway, and low IGF-I expression. Fasting leads to further elevation of plasma GH levels concomitant with suppressed IGF-I levels. The ratio of GHRfl to GHRt in muscle decreases during fasting, causing an inactivation of the JAK2/STAT5 signaling pathway and suppressed IGF-I expression, further impairing growth. When fish are returned to nutritionally favorable conditions, plasma GH levels decrease, and the ratio of GHRfl to GHRt in muscle increases, triggering JAK2/STAT5 reactivation and local IGF-I expression, concomitant with increased growth. The study suggests that systemic IGF-I is supporting basal slow growth in this species, without ruling out that local IGF-I is participating in muscle growth. These results reveal for the first time a unique model of inherent GH resistance in the skeletal muscle of a nonmammalian species and contribute to novel insights of the endocrine and molecular basis of growth regulation in earlier vertebrates.

Sperm concentration at freezing affects post-thaw quality and fertility of ram semen

We have investigated the effect of sperm concentration in the freezing doses 200, 400, 800, and 1600 × 10(6) mL(-1) on the post-thaw quality and fertility of ram semen. Semen was collected from seven adult Churra rams by artificial vagina during the breeding season. The semen was diluted in an extender (TES-Tris-fructose, 20% egg yolk, and 4% glycerol), to a final concentration of 200, 400, 800, or 1600 × 10(6) mL(-1) and frozen. Doses were analyzed post-thawing for motility (computer-assisted sperm analysis system [CASA]), viability, and acrosomal status (fluorescence probes propidium iodide [PI]/peanut agglutinin conjugated with fluorescein thiocyanate (PNA-FITC), SYBR-14/PI [Invitrogen; Barcelona, Spain] and YO-PRO-1/PI [Invitrogen; Barcelona, Spain]). Total motility and velocity were lower for 1600 × 10(6) mL(-1) doses, while progressive motility and viability were lower both for 800 and 1600 × 10(6) mL(-1). The proportion of viable spermatozoa showing increased membrane permeability (YO-PRO-1+) rose in 800 and 1200 × 10(6) mL(-1). Intrauterine inseminations were performed with the 200, 400, and 800 × 10(6) mL(-1) doses at a fixed sperm number (25 × 10(6) per uterine horn) in synchronized ewes. Fertility (lambing rate) was similar for semen frozen at 200 (57.5%) or 400 × 10(6) mL(-1) (54.4%), whereas it was significantly lower for 800 × 10(6) mL(-1) (45.5%). In conclusion, increasing sperm concentration in cryopreserved semen, at least at 800 × 10(6) mL(-1) and more, adversely affects the postthawing quality and fertility of ram semen.

P4-11-06: Uptake of Selective Estrogen Receptor Modulators and Other Breast Cancer Prevention Strategies among High-Risk Women Seen in a Breast Center

Background: Selective estrogen receptor modulators (SERMs), tamoxifen and raloxifene, are FDA-approved for breast cancer (BC) risk reduction. However, uptake has been poor in the prevention setting, partly due to a lack of knowledge in the medical community about BC prevention and public misconceptions about the risks of SERMs. We assessed demographic and clinical factors that influence SERM uptake among high-risk women seen in an academic breast center, where specialized risk counseling is provided by a breast surgeon or medical oncologist.

Methods: Potential subjects included high-risk women seen for an initial consultation by Breast Surgery or Medical Oncology. Eligibility for SERM use included a 5-year Gail risk ≥1.67%, lobular carcinoma in situ (LCIS), BRCA mutation carrier, or estrogen receptor (ER)-positive and/or progesterone receptor (PR)-positive ductal carcinoma in situ (DCIS). Demographic and BC risk factor data was collected from self-administered questionnaires. Clinical data, including prior/current SERM use, was abstracted from medical chart review. Differences in distribution of risk factors, between women who ever took a SERM and those who did not, were examined using chi-square statistics or Fisher's exact test. Multivariable logistic regression models were used to calculate odds ratios (OR) and 95% confidence intervals using SERM use as the dependent variable.

Results: Among 247 high-risk women enrolled between March 2007 and January 2011, median age 51 (17-82); White/Hispanic/Black/Asian (%): 55/32/7/6. 85% of women were undergoing annual mammography, 94% had a breast biopsy, 19% genetic testing, and 71% Medical Oncology referral. Among 181 (73%) women eligible for a SERM, Gail risk ≥1.67%/LCIS/DCIS/BRCA mutation (%): 35/22/39/3; 83 (46%) ever took a SERM, including 62 on tamoxifen and 21 on raloxifene. Early SERM discontinuation was only 7%. In multivariable analysis, significant predictors of SERM uptake included risk category (DCIS vs. Gail risk ≥1.67%/LCIS/BRCA mutation), higher income, higher body mass index (BMI), and referral to Medical Oncology. In terms of this high-risk population meeting American Cancer Society (ACS) behavioral guidelines for cancer prevention, 53% had a BMI <25 kg/m2, 44% consumed ≤1 alcoholic beverage per day, and 10% engaged in ≥4 hours of moderate physical activity per week; only 3.5% met all 3 recommendations.

Conclusions: Among high-risk women seen at a specialized breast center, application of clinical recommendations such as screening mammography, genetic testing, and SERM uptake were relatively high, suggesting that a comprehensive approach to the management of high-risk women is feasible. However, meeting ACS nutrition and physical activity guidelines for cancer prevention was limited, perhaps due to a lack of reimbursable staff to implement these guidelines. Breast cancer risk assessment and available interventions for prevention among high-risk women are underutilized in the U.S. Future studies should focus on the development and delivery of breast cancer prevention strategies.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-11-06.

P3-05-04: Changes in Recurrence Risk of Breast Cancer Intrisic Subtypes over Time

Background: Gene expression profiling and their immunohistochemistry-based surrogates have consistently revealed prognostically significant breast cancer (BC) subtypes: Luminal A (Lum A), Luminal B (Lum B), HER2, Basal-like (BL) and Triple negative phenotype-nonbasal (TNP-nb). In addition, there are clinical evidence that hazard of BC recurrence varies over time with two peaks of high risk at 18–24 and 60 months. This study compares the time-related patterns of recurrence within BC subtypes. Methods: Tissue microarrays were constructed from 937 early BC patients diagnosed and treated at our Hospital from 1982 to 2005 with available archival paraffin tissue blocks. BC subtypes were defined using an immunopanel of estrogen receptor, progesterone receptor, HER2, epidermal growth factor receptor, cytokeratin 5/6 and Ki67 by prespecified published methods. Univariate and multivariate analysis (Cox regression) were performed on progression-free survival. Smoothed curves for hazard rates (HR) were estimated by a Kernel-like smoothing procedure. The statistical analysis was done by using the R software environment.

Results: Cases were classified as follows: Lum A 46.8%, Lum B 25.2%, HER2 11.3%, BL 11.3%, TNP-nb 5.4%. None of the patients were treated with adjuvant trastuzumab. With a median follow up of 80 months age, tumor size, nodal status and intrinsic subtypes were independent prognostic factors. HER2 and BL show high and early peak in HR curves and decreasing sharply to 36 and 48 months respectively. HR in Lum A, Lum B and TNP-nb exhibit a smoother and nearly steady curve.

Evaluation of the qualitative and quantitative effectiveness of three media of centrifugation (Maxifreeze, Cushion Fluid Equine, and PureSperm 100) in preparation of fresh or frozen-thawed brown bear spermatozoa

Centrifugation is a crucial procedure in sperm cryopreservation protocols of brown bear (Ursus arctos), because the semen must be processed to increase sperm concentration and/or clean urine-contaminated samples. The efficacy of three media for centrifugation (Maxifreeze [IMV technologies, L'Aigle, France], Cushion Fluid Equine (Minitübe, Tiefenbach, Germany), and PureSperm [Nidacon, Gothenburg, Sweden]) on the quality of bear spermatozoa was evaluated. In experiment one, two cushioned media used for protecting against mechanical stress during centrifugation were analyzed. In experiment two, a density gradient based on PureSperm was assessed in relation to the maximum retrieval and the quality of fresh spermatozoa, and the freezability of the spermatozoa selected in this density gradient was studied in experiment three. Finally, the selection of frozen-thawed sperm using PureSperm was analyzed in experiment four. Our results indicate that the use of dense isotonic cushion solutions (Maxifreeze, Cushion Fluid Equine) in centrifugation did not improve the quality of recovered spermatozoa compared with standard centrifugation. However, a density gradient prepared with PureSperm improved the quality of spermatozoa in fresh semen and frozen-thawed semen, but the spermatozoa selected from the fresh sample with this density gradient did not show a better resistance to freezing with this density gradient in comparison with the control sample.

Cell death causes relocalization of photosensitizing fluorescent probes

When cultured cells are treated with fluorescent organelle probes or photosensitizer agents, a characteristic redistribution of fluorescence in cell structures occurs frequently after light irradiation. It is currently assumed that such changes, referred to as relocalizations of the fluorescent compounds, represent an important aspect of the photodynamic process, which is based on the excitation of photosensitizers by light in the presence of oxygen. As cell damage and death result from the oxidative stress induced by photodynamic treatments, we have studied here the redistribution of acridine orange (AO) and 3,3'-dimethyl-oxacarbocyanine (DiOC(1)(3)) fluorescence after incubation of HeLa cell cultures with these compounds followed by blue light irradiation to achieve lethal effects. The relocalization of dyes from their original labeling sites (AO: lysosomes, DiOC(1)(3): mitochondria) to nucleic acid-containing structures (cytoplasm, nuclei and nucleoli) appeared clearly associated with cell death. Therefore, the relocalization phenomenon simply reflects fluorescence changes due to the different affinity of these dyes for living and damaged or dead cells. As fluorescent probes are often photosensitizers, prolonged light exposures using fluorescence microscopy will produce lethal photodynamic effects with relocalization of the fluorescent signal and changes in the cell morphology.

Molecular cloning of IGF-1 and IGF-1 receptor and their expression pattern in the Chilean flounder (Paralichthys adspersus)

Insulin-like growth factor-1 and insulin-like growth factor-1 receptor (IGF-1 and IGF-1R) play main roles in vertebrate growth and development. In fish, besides contributing to somatic growth, both molecules exhibit pleiotropic functions. We isolated complete cDNAs sequences encoding for both IGF-1 and IGF-1R in the Chilean flounder by using RT-PCR and rapid amplification of cDNAs ends (RACE) techniques. We analyzed gene expression in pre-metamorphic larvae and different organs of juvenile fish through whole mount in situ hybridization and RT-PCR, respectively. In addition, we studied the presence of calcified skeletal structures in pre-metamorphic larvae through the fluorescent chromophore calcein. The IGF-1 cDNA sequence displays an open reading frame of 558 nucleotides, encoding a 185 amino acid preproIGF-1. Moreover, IGF-1R contains an open reading frame spanning 4239 nucleotides, rendering a 702 amino acid subunit alpha and a 676 amino acid subunit beta. The deduced mature IGF-1 and IGF-1R exhibited high sequence identities with their corresponding orthologs in fishes, especially those domains involved in biological activity. RT-PCR showed expression of IGF-1 and IGF-1R transcripts in all studied tissues, consistent with their pleiotropic functions. Furthermore, we observed IGF-1 expression in notochord and IGF-1R expression in notochord, somites and head in larvae of 8 and 9 days post fertilization. Complementarily, we detected in larvae of 8 days post fertilization the presence of calcified skeletal structures in notochord and head. Interestingly, both mRNAs and calcified structures were found in territories such as notochord, an embryonic midline structure essential for the pattern of surrounding tissues as nervous system and mesoderm. Our results suggest that IGF-1 and its receptor play an important role in the development of the nervous system, muscle and bone-related structures during larval stages.

IGF-I/PI3K/Akt and IGF-I/MAPK/ERK pathways in vivo in skeletal muscle are regulated by nutrition and contribute to somatic growth in the fine flounder

The insulin-like growth factor-I (IGF-I) is a key regulator of skeletal muscle growth in vertebrates, promoting mitogenic and anabolic effects through the activation of the MAPK/ERK and the PI3K/Akt signaling pathways. Nutrition also affects skeletal muscle growth, activating intracellular pathways and inducing protein synthesis and accretion. Thus, both hormonal and nutritional signaling regulate muscle mass. In this context, plasma IGF-I levels and the activation of both pathways in response to food were evaluated in the fine flounder using fasting and refeeding trials. The present study describes for the first time in a nonmammalian species that the MAPK/ERK and PI3K/Akt are activated by exogenous circulating IGF-I, as well as showing that the MAPK/ERK pathway activation is modulated by the nutritional status. Also, these results show that there is a time-dependent regulation of IGF-I plasma levels and its signaling pathways in muscle. Together, these results suggest that the nutritionally managed IGF-I could be regulating the activation of the MAPK/ERK and the PI3K/Akt signaling pathways differentially according to the nutritional status, triggering different effects in growth parameters and therefore contributing to somatic growth in fish. This study contributes to the understanding of the nutrient regulation of IGF-I and its signaling pathways in skeletal muscle growth in nonmammalian species, therefore providing insight concerning the events controlling somatic growth in vertebrates.

Reclaimed wastewater quality enhancement by oxygen injection during transportation

In-sewer treatments have been studied in sewer systems, but few have been carried out on reclaimed wastewater systems. A study of oxygen injection has been performed in a completely filled gravity pipe, 0.6 m in diameter and 62 km long, in cast iron with concrete inside coating, which is part of the reclaimed wastewater reuse scheme of Tenerife (Spain). A high pressure oxygen injection system was installed at 16.0 km from pipe inlet and a constant dosage of 30 mg/L O(2) has been injected during six months, under three different operational modes (low COD, 63 mg/L; high COD, 91 mg/L; and partially nitrified water). Oxygen has been consumed in nitrification and organic matter reduction. Generally, nitrification is clearly favored instead of the organic matter oxidation. Nitrification occurs, in general, with nitrite accumulation due to the presence of free ammonia above 1 mg/L. Denitrification is in all cases incomplete due to a limitation of easily biodegradable organic matter content, inhibiting the appearance of anaerobic conditions and sulfide generation. A notable reduction of organic matter parameters is achieved (TSS below 10 mg/L), which is significantly higher than that observed under the ordinary transport conditions without oxygen. This leads to a final cost reduction, and the oxygen injection system helps water reuse managers to maintain a final good water quality in the case of a treatment plant malfunction.

Bacteraemia following dental implants' placement

OBJECTIVE

To investigate the prevalence, duration and aetiology of bacteraemias following the placement of implants as well as the prophylactic efficacy of a chlorhexidine digluconate (CHX) mouthrinse.

MATERIAL AND METHODS

Fifty patients undergoing implant placement were randomly distributed into two groups:

CONTROL GROUP

30 patients with no prophylactic intervention before surgery. CHX group: 20 patients who performed a 0.2% CHX mouthrinse before surgery. Blood samples were collected at baseline, at 30 s after the insertion of implants and at 15 min after completion of the suturing of the mucoperiosteal flap. Samples were processed in the Bactec 9240, and the subculture and further identification of the isolates were performed using conventional microbiological techniques.

RESULTS

The prevalence of bacteraemias was 2% at baseline. In the control group, the prevalence of bacteraemias was 6.7% at 30 s and 3.3% at 15 min, but no statistically significant differences were achieved compared with the baseline percentage. In the CHX group, there were no positive cultures from blood samples obtained at 30 s or at 15 min.

CONCLUSIONS

Implant placement via a mucoperiosteal flap does not carry a significant risk of developing bacteraemias. The use of antibiotic prophylaxis for the prevention of focal infections such as bacterial endocarditis in "at-risk" patients undergoing dental implants is therefore questionable. Although its efficacy has not been confirmed statistically, we recommend a 0.2% CHX mouthrinse before treatment as proposed previously by the British Society for Antimicrobial Chemotherapy.

Episodes of overtreatment during the first six months in children with congenital hypothyroidism and their relationships with sustained attention and inhibitory control at school age

BACKGROUND/AIMS

Contradictory results regarding the optimal initial dose of levothyroxine in children with congenital hypothyroidism (CH) hamper the clinical management of these children during their early infancy. We explore the relationships between the initial dose of levothyroxine and endocrine control during the first 6 months and cognition at school age.

SUBJECTS AND METHODS

Fifty children with CH, 14 boys (10+/-3.1 years) and 36 girls (9.7+/-2.6 years), at the Pediatric Endocrine Unit of the Hospital Gregorio Marañón in Madrid were studied. Neurocognitive evaluation was carried out exploring alertness and inhibitory control. The number of episodes of overtreatment during the first 6 months, the initial dose of levothyroxine, etiology and sex were the predictor variables.

RESULTS

Inhibitory control was significantly lower in children with CH than in controls. An interaction with gender and etiology was obtained. Alertness had an inverse relationship with the number of episodes of overtreatment with no interaction with gender or etiology.

CONCLUSION

Episodes of overtreatment and not the initial dose of levothyroxine are a risk factor for deficit in alertness whereas subtle inhibitory control deficit seems to be a permanent problem with the current therapeutic approach.