Epidemiology and impact of methicillin-sensitive Staphylococcus aureus with ß-lactam antibiotic inoculum effects in adults with cystic fibrosis.

Staphylococcus aureus is the most prevalent cystic fibrosis (CF) pathogen. Several phenotypes are associated with worsened CF clinical outcomes including methicillin-resistance and small-colony-variants. The inoculum effect (IE) is characterized by reduced ß-lactam susceptibility when assessed at high inoculum. The IE associates with worse outcomes in bacteremia and other high-density infections, and may therefore be relevant to CF. The prevalence of IE amongst a CF cohort (age ≥18 years), followed from 2013 to 2016, was investigated. Yearly methicillin-sensitive S. aureus (MSSA) isolates were screened at standard (5 × 105 CFU/mL) and high (5 × 107 CFU/mL) inoculum against narrow-spectrum anti-Staphylococcal ß-lactams and those with anti-pseudomonal activity common to CF. A ≥ 4-fold increase in minimum inhibitory concentration between standard and high inoculum defined IE. Isolates underwent blaZ sequencing and genotyping and were compared against published genomes. Fifty-six percent (99/177) of individuals had MSSA infection. MSSA was observed at ≥105 CFU/mL in 44.8% of entry sputum samples. The prevalence of the IE was 25.0%-cefazolin; 13.5%-cloxacillin; 0%-meropenem; 1.0%-cefepime; 5.2%-ceftazidime; and 34.4%-piperacillin-tazobactam amongst baseline MSSA isolates assessed. blaZ A associated with cefazolin IE (P = 0.0011), whereas blaZ C associated with piperacillin-tazobactam IE (P < 0.0001). Baseline demographics did not reveal specific risk factors for IE-associated infections, nor were long-term outcomes different. Herein, we observed the IE in CF-derived MSSA disproportionally for cefazolin and piperacillin-tazobactam and this phenotype strongly associated with underlying blaZ genotype. The confirmation of CF being a high density infection, and the identification of high prevalence of MSSA with IE in CF supports the need for prospective pulmonary exacerbation treatment studies to understand the impact of this phenotype.

Influence of follicle-stimulating hormone concentrations on the integrity and development of bovine follicles cultured in vitro.

SummaryThis study investigated the in vitro culture of bovine follicles included in ovarian tissue for 2 or 6 days (D2 or D6), with the addition of different concentrations of follicle-stimulating hormone (FSH) (0, 10, 50, 100 or 200 ng/ml). Data were compared for follicular development, morphological integrity and diameter of follicles and oocytes. Ovaries (n = 10) from Nelore cows (n = 5) were divided into fragments (n = 11 per ovary) and were immediately fixed in Bouin's solution (D0) or were individually cultured for 2 or 6 days in one of the described concentrations of FSH and then processed for histology. Compared with the rates of follicular development at D2 for minimal essential medium (MEM) (75.0%) and 50 ng/ml of FSH (71.1%), the best rates of follicular development at D2 were obtained with 10 (84.7%), 100 (87.5%) and 200 ng/ml of FSH (85.0%; P<0.05). After 6 days of cultivation, there were no differences among treatments regarding follicular growth. The morphological integrity of preantral follicles was better maintained by 100 ng/ml FSH for 2 and 6 days of cultivation (51.2 and 40.4%, respectively; P<0.05) than that for MEM (D2: 30.9%, D6: 20.8%), 10 (D2: 39.2%, D6: 22.8%), 50 (D2: 30.4%, D6: 28.8%) and 200 ng/ml FSH (D2: 45.2%, D6: 36.8%). FSH at 100 ng/ml provided the highest mean diameter averages: 34.5±10.8 µm at D2 and 33.2±12.5 µm at D6 (P<0.05). We concluded that the medium supplemented with 100 ng/ml FSH during in vitro culture provided appropriate conditions for the development and morphological integrity of preantral follicles in cattle.

Regional distribution and integrity of equine ovarian pre-antral follicles.

The goal of this study was to determine the distribution of pre-antral follicles in the ovarian parenchyma of mares. For Experiment 1, each ovary was cut longitudinally at the greater curvature, performing two hemiovaries. After that, six fragments from each hemiovary were obtained, resulting in 12 fragments, which were divided into the innermost region of the parenchyma, the middle region and the outermost region. All the three obtained sections were cut transversally to obtain two fragments from each one. For Experiment 2, each ovary also submitted to a longitudinal cut on the greater curvature, forming two hemiovaries. Each hemiovary was sectioned into four symmetrical fragments, resulting in eight fragments per ovary. The fragments were related as being near to or far from the ovulatory fossa. The fragments of both experiments were immediately fixed in Carnoy for 12 hr and kept in 70% ethanol for 24 hr. Follicles were classified according to the stages of development and for morphological integrity according to oocyte morphology and granulosa cells. After the histological assessment, a total of 1,130 follicles were visualized from Experiment 1, being 1,054 (93.3%) primordial follicles and 76 (4.7%) follicles in development. The innermost region had the highest percentage of pre-antral follicles compared to the other regions (p < .05). The middle and outermost regions showed higher percentages of intact primordial and developing follicles than the innermost region (p < .05). Considering Experiment 2, 938 follicles were found, being 894 (95.3%) primordial and 44 (4.7%) follicles in development. The region near the ovulatory fossa presented higher (58.7%; 551 of 938) follicular concentration compared to the region far from the ovulatory fossa (41.3%; 387 of 938; p < .05). As a conclusion, distribution of pre-antral follicles in the equine ovary has a specific pattern through the parenchyma. Also, the follicular integrity differed in the studied ovarian areas.

The development and integrity of equine pre-antral follicles cultured in vitro with follicle-stimulating hormone (FSH) supplementation.

This study investigated the effects of different concentrations of FSH (10, 50, 100 and 200 ng/ml) in supplemented MEM+ on the development of equine pre-antral follicles that were cultured in vitro for 2 or 6 days. The ovaries (n = 5) from mares in seasonal anoestrus were collected from a local abattoir. Ten ovarian tissue fragments of approximately 3 × 3 × 1 mm were obtained from each animal. The fragments were cultured in situ for 2 days (D2) or 6 days (D6) in MEM+ or MEM+ supplemented with FSH at four different concentrations, establishing the following 11 groups: control (D0); MEM + (D2); MEM + (D6); MEM + 10 ng/ml of FSH (D2); MEM + 10 ng/ml of FSH (D6); MEM + 50 ng/ml of FSH (D2); MEM + 50 ng/ml of FSH (D6); MEM + 100 ng/ml of FSH (D2); MEM + 100 ng/ml of FSH (D6); MEM + 200 ng/ml of FSH (D2); and MEM + 200 ng/ml of FSH (D6). Follicles were observed in only 9.65% (388 of 4,018) of the histological sections. Of the 861 follicles evaluated, 488 were in the primordial stage, and 373 were in various developmental stages; 59.7% were morphologically normal. Regarding the integrity of the pre-antral follicles, the groups with 100 ng/ml FSH of 2-days culture as well as 50, 100 and 200 ng/ml FSH of 6-days culture provided the best results. In conclusion, the in vitro culture of abattoir-derived equine ovarian fragments presented better morphological integrity when supplemented with FSH for 6 days, in comparison with the MEM culture group. However, no clear effects were observed with FSH regarding the promotion of activation from a primordial to a developing follicle.

Complexity of Host Micro-RNA Response to Cytomegalovirus Reactivation After Organ Transplantation.

Human (Homo sapiens) micro-RNAs (hsa-miRNAs) regulate virus and host-gene translation, but the biological impact in patients with human cytomegalovirus (hCMV) infection is not well defined in a clinically relevant model. First, we compared hsa-miRNA expression profiles in peripheral blood mononuclear cells from 35 transplant recipients with and without CMV viremia by using a microarray chip covering 847 hsa-miRNAs. This approach demonstrated a set of 142 differentially expressed hsa-miRNAs. Next, we examined the effect of each of these miRNAs on viral growth by using human fibroblasts (human foreskin fibroblast-1) infected with the hCMV Towne strain, identifying a subset of proviral and antiviral hsa-miRNAs. miRNA-target prediction software indicated potential binding sites within the hCMV genome (e.g., hCMV-UL52 and -UL100 [UL = unique long]) and host-genes (e.g., interleukin-1 receptor, IRF1). Luciferase-expressing plasmid constructs and immunoblotting confirmed several predicted miRNA targets. Finally, we determined the expression of selected proviral and antiviral hsa-miRNAs in 242 transplant recipients with hCMV-viremia. We measured hsa-miRNAs before and after antiviral therapy and correlated hsa-miRNA expression levels to hCMV-replication dynamics. One of six antiviral hsa-miRNAs showed a significant increase during treatment, concurrent with viral decline. In contrast, six of eight proviral hsa-miRNAs showed a decrease during viral decline. Our results indicate that a complex and multitargeted hsa-miRNA response occurs during CMV replication in immunosuppressed patients. This study provides mechanistic insight and potential novel biomarkers for CMV replication.

CCL8 and the Immune Control of Cytomegalovirus in Organ Transplant Recipients.

Monitoring of cytomegalovirus cell-mediated immunity is a promising tool for the refinement of preventative and therapeutic strategies posttransplantation. Typically, the interferon-γ response to T cell stimulation is measured. We evaluated a broad range of cytokine and chemokines to better characterize the ex vivo host-response to CMV peptide stimulation. In a cohort of CMV viremic organ transplant recipients, chemokine expression-specifically CCL8 (AUC 0.849 95% CI 0.721-0.978; p = 0.003) and CXCL10 (AUC 0.841, 95% CI 0.707-0.974; p = 0.004)-was associated with control of viral replication. In a second cohort of transplant recipients at high-risk for CMV, the presence of a polymorphism in the CCL8 promoter conferred an increased risk of viral replication after discontinuation of antiviral prophylaxis (logrank hazard ratio 3.6; 95% CI 2.077-51.88). Using cell-sorting experiments, we determined that the primary cell type producing CCL8 in response to CMV peptide stimulation was the monocyte fraction. Finally, in vitro experiments using standard immunosuppressive agents demonstrated a dose-dependent reduction in CCL8 production. Chemokines appear to be important elements of the cell-mediated response to CMV infection posttransplant, as here suggested for CCL8, and translation of this knowledge may allow for the tailoring and improvement of preventative strategies.

Hcmv-miR-UL22A-5p: A Biomarker in Transplantation With Broad Impact on Host Gene Expression and Potential Immunological Implications.

Cytomegalovirus (CMV) encodes multiple microRNAs. While these have been partially characterized in vitro, their relevance to clinical CMV infection has not been evaluated. We analyzed samples from a cohort of solid organ transplant patients with CMV disease (n = 245) for viral microRNA expression. Several CMV microRNAs were readily detectable in patients with CMV disease in variable relative abundance. Expression level generally correlated with DNA viral load and the absence of viral microRNA was associated with faster viral clearance. Detection of hcmv-miR-UL22A-5p at baseline independently predicted the recurrence of CMV viremia upon discontinuation of antiviral therapy (OR 3.024, 95% CI: 1.35-6.8; p = 0.007). A combination of direct mRNA targeting by the microRNA and indirect modulation of gene expression involving isoforms of the transcriptional regulator C-MYC may be responsible for the broad effects seen in the association of gene transcripts with the RNA-induced silencing complex and in global protein expression upon hcmv-miR-UL22A-5p transfection. This novel study of in vivo viral microRNA expression profiles provides unique insight into the complexity of clinical CMV infection following transplantation. We provide evidence that viral microRNAs may have complex effects on gene expression and be associated with specific virologic and clinical outcomes, and thus could be further evaluated as biomarkers.

Analysis and clinical correlation of genetic variation in cytomegalovirus.

BACKGROUND: Cytomegalovirus (CMV) displays genetic polymorphisms in multiple genes, which may result in important virulence differences. Glycoprotein N (gN) and immediate early 1 (IE1) are key viral genes and immune targets. We aimed to characterize the molecular epidemiology of gN and IE1 genotypes in organ transplant patients with CMV disease in the context of clinical and virologic endpoints. METHODS: A total of 240 patients with CMV disease had genotyping analysis by nested polymerase chain reaction assays and sequencing using blood samples obtained at disease onset. Results were correlated with viral clearance kinetics and recurrence. RESULTS: Complex patterns of gN and IE1 genotypes were present with no clear genetic linkages. No single genotype of IE1 or gN was associated with poorer outcome. For example, different gN or IE1 genotypes had comparable baseline viral load, clearance half-lives, time to clearance, and rates of virologic recurrence. Mixed infection was present at IE1 in 15.8% and gN in 21.9%, but analysis of a single gene was insufficient to detect all mixed infections. Infections caused by multiple strains, as opposed to single strains, were associated with higher baseline viral loads (P = 0.011), delayed viral clearance (P = 0.033), and higher rates of virologic recurrence (P = 0.008). CONCLUSIONS: Genetic diversity in CMV is complex. Specific gN or IE subtypes do not seem to affect in vivo viral virulence patterns in single-strain infections. Mixed infections demonstrate associations with virologic outcomes that single-strain infections do not.

Morphology of the spermatheca of Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859).

Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) is a potential vector of Chagas's disease and the comprehension of its reproductive biology is an important tool to control this insect. In the reproductive tract of female insects, the spermatheca plays a crucial role storing male spermatozoa after mating. Whithin insects the spermatheca shows a wide morphological diversity and the analysis of this characteristic can contribute to understand the reproductive biology of the species. This study describes the histology and histochemistry of the spermatheca of T. lecticularia. Females have a pair of elongated spermathecal reservoirs without associated accessory gland. The reservoir opens into the common oviduct via a narrow muscular duct. The reservoir epithelium has single layer of columnar secretory cells. The control of the release of spermatozoa from the spermatheca occurs via the muscular duct. The anatomical features of the spermatheca of T. lecticularia resemble those described of other Reduviidae. However, the histological and histochemical features of spermatheca observed in T. lecticularia were important to explain the maintenance of the viability of the spermatozoa stored.

Alpha lipoic acid (ALA) effects on developmental competence of equine preantral follicles in short-term culture.

The effect of different concentrations of alpha lipoic acid (ALA) on the development and morphology of preantral follicles, as well as the proliferative activity of granulosa cells, was assessed after short-term culture. Ovaries (n = 5) of five seasonal anestrous mares were harvested in a local abattoir. At the laboratory, nine ovarian fragments (5 × 5 × 1 mm) from each animal were used. One fragment was immediately fixed in Bouin and subjected to histological and immunohistochemistry (proliferating cell nuclear antigen, PCNA) analyses (noncultured group; D0 = day 0). The other eight fragments were cultured in situ for two (D2) or six (D6) days in MEM+ or MEM+ plus ALA (50, 100, or 250 µM). After culture, fragments were subjected to histology and PCNA analyses. After two days of culture, ALA 50 and ALA 100 had the greatest (P < 0.05) percentage of normal primordial follicles (97.2 and 95.1%, respectively), when compared to other groups, and did not differ (P > 0.05) from the fresh noncultured control group. Furthermore, the total percentage of normal follicles was greater (P < 0.05) in the ALA 50 and ALA 100 than in the MEM-D2 group. After six days of culture, the highest (P < 0.05) proliferative activity of granulosa cells in developing follicles was observed for the groups MEM+ (92.9%), ALA 50 (100%), and ALA 100 (96.4%). In conclusion, the results of this study demonstrated that (1) ALA 50 and ALA 100 preserved the morphological integrity of equine primordial follicles for up two days of culture, and (2) granulosa cells of developing follicles enclosed in ovarian tissue and cultured for up to six days in MEM+ with or without ALA were highly stained by PCNA.

Development of antennal sensilla of Tetragonisca angustula Latreille, 1811 (Hymenoptera: Meliponini) during pupation.

The antennal sensilla are sensory organs formed by a group of neurons and accessory cells, which allow perception of environmental cues, which play a role as mechanoreceptors and chemoreceptors. This study describes the post-embryonic development of the antennal sensilla of the stingless Tetragonisca angustula (Hymenoptera: Meliponini) workers. The development of the antennal sensilla begins in the transition stage of the pre-pupae to white-eyed pupae. The sensilla are completely developed at the black-eyed pupae stage, but they are covered by the old cuticle. The sensilla are exposed to the environment only in newly emerged workers of T. angustula, but it is possible that environmental stimuli can be recognized due to the pores in the old cuticle.

Oral follicular lymphoid hyperplasia: clinicopathologic of a case series / Hiperplasia linfoide folicular oral: clinicopatológico de uma série de casos

RESUMEN La hiperplasia folicular linfoide (HFL) es una proliferación linfoide reactiva que puede simular linfomas, tanto clínica como histológicamente. El objetivo de este estudio fue investigar las características clínicas, morfológicas e inmunohistoquímicas de una serie de casos de HFL en la cavidad oral y discutir importantes aspectos diagnósticos y diagnósticos diferenciales en relación con los linfomas foliculares. Un análisis retrospectivo de los registros de una base de datos de 38 años reveló nueve casos diagnosticados como HFL de la cavidad oral. La edad de los pacientes osciló entre 8 y 44 años. La mayoría de las lesiones se localizaron en la mucosa oral y la presencia de un nódulo indoloro fue el hallazgo clínico más común. El análisis histopatológico reveló proliferación de células linfoides dispuestas en patrón folicular, presentando folículos primarios y secundarios con centro germinal y zona del manto, con evidencia de macrófagos que contenían cuerpos apoptóticos en su interior, así como evidencia de figuras de mitosis típicas. Observamos el área interfolicular, los linfocitos, los macrófagos e las islas epimioepiteliales. El análisis inmunohistoquímico reveló positividad de folículos linfoides para CD20, CD68, CD3 y linfoma de células B2 (Bcl-2). La presentación clínica de HFL y las evidencias histopatológicas de folículos linfáticos que muestran centros germinales indistintos con una zona del manto mal definida pueden ser un problema debido a la similitud con el linfoma folicular.

Improvement of development of equine preantral follicles after 6 days of in vitro culture with ascorbic acid supplementation.

The aim of this study was to evaluate the effects of different concentrations of ascorbic acid (25, 50, and 100 µg/mL) in supplemented minimum essential medium (MEM+) on the development of equine preantral follicles that were cultured in vitro for 2 or 6 days. The contralateral ovaries (n = 5) from five mares in seasonal anestrus were collected from a local abattoir. Nine ovarian tissue fragments of approximately 5 × 5 × 1 mm were obtained from each animal. One fragment was immediately fixed and subjected to histologic analysis (control group; Day 0), and the other eight were placed in PBS supplemented with penicillin (200 IU/mL) and streptomycin (200 mg/mL) at 4 °C for 1 hour (during transport to the laboratory). The fragments were cultured in situ for 2 days (D2) or 6 days (D6) in MEM+ or MEM+ plus ascorbic acid at three different concentrations, establishing the following nine groups: control; MEM+ (D2); MEM+ (D6); MEM+ 25 µg/mL of ascorbic acid (D2); MEM+ 25 µg/mL of ascorbic acid (D6); MEM+ 50 µg/mL of ascorbic acid (D2); MEM+ 50 µg/mL of ascorbic acid (D6); MEM+ 100 µg/mL of ascorbic acid (D2); and MEM+ 100 µg/mL of ascorbic acid (D6). The preantral follicles were classified according to their stage (primordial, primary, secondary, or antral) and their morphology (normal or abnormal). Slides (n = 951) including 4450 histologic sections were evaluated. Follicles were observed in only 4.85% (216 of 4450) of the histologic sections. Of the 407 follicles evaluated, 120 were in the primordial stage and 287 were in different developmental stages; additionally, 43.5% were morphologically normal. After 6 days of culture, the groups cultured with 50 and 100 µg/mL of ascorbic acid differed in terms of follicular development compared with the other groups. On the basis of occurrence of follicular development and the presence of viable follicles, it can be concluded that a positive effect of culture for 6 days in MEM+ supplemented with 50 and 100 µg/mL of ascorbic acid was observed on equine ovarian fragments.

A prospective comparison of Doppler echocardiography and postoperative angiography in the assessment of left internal thoracic artery graft in 72 patients submitted to minimally invasive direct coronary artery bypass.

BACKGROUND: Concerns have been raised regarding the accuracy of the left internal thoracic artery (LITA) anastomosis performed during minimally invasive direct coronary artery bypass (MIDCAB). In a prospective study, we tested the hypothesis that transthoracic Doppler echocardiography is an adequate technique to determine LITA patency when compared to "gold standard" postoperative angiography. METHODS: Seventy-two consecutive patients with single left anterior descending (LAD) coronary artery stenosis were submitted to MIDCAB performed on a beating heart using the LITA. All patients underwent transthoracic Doppler Echocardiography and angiography before discharge. LITA was considered patent when diastolic fraction (DF) of time-velocity integral was equal or greater than 0.5. FitzGibbon grading system was used to evaluate LITA patency by angiography (A=excellent; B=stenosis reducing caliber of anastomosis or trunk to < 50% of grafted coronary artery; O=occlusion). RESULTS: Angiography showed that LITA was patent in 70 (97.2%) patients, 69 of them been graded A. Adequate image and flow signal of the LITA was achieved in 65 (90.3%) patients, been considered patent in 61 (93.8%) of them. Comparison between echocardiography and angiography in these 65 patients showed a specificity of 96.8% and a sensitivity of 50%. In 7 (9.7%) patients in whom no adequate echocardiography signal was obtained, the LITA graft was normal in six and occluded in one. CONCLUSIONS: For patients whose LITA graft can be imaged, transthoracic Doppler echocardiography is highly specific and is a valuable method for noninvasive evaluation of LITA graft patency after MIDCAB.

[Combined lateral gaze palsy with unilateral internuclear ophthalmoplegia in high mesencephalic-pontine hemorrhage. Report of a case]. / Paralisia do olhar conjugado lateral associada a oftalmoplegia internuclear unilateral em hemorragia mesencéfalo-pontina alta. Relato de um caso.

The authors report a case of right midbrain and high pons haemorrhage with complete external ophthalmoplegia, except bilateral convergence, voluntary and automatic-reflex abduction of the left eye and adduction of this eye with vestibulo-ocular reflex ("one-and-a-half syndrome"). There is voluntary-automatic dissociation of the eyelids motricity and the vertical gaze. Still, there is sensitive-motor hemiplegia at left and asterixis.

Myocardial revascularization with coronary endarterectomy. Stratification of risk factors for early mortality.

OBJECTIVE: To determine the risk factors for mortality related to myocardial revascularization when performed in association with coronary endarterectomy. METHODS: We assessed retrospectively 353 patients who underwent 373 coronary endarterectomies between January '89 and November '98, representing 3.73% of the myocardial revascularizations in this period of time. The arteries involved were as follows: right coronary artery in 218 patients (58.45%); left anterior descending in 102 patients (27.35%); circumflex artery in 39 patients (10.46%); and diagonal artery in 14 patients (3.74%). We used 320 (85.79%) venous grafts and 53 (14.21%) arterial grafts. RESULTS: In-hospital mortality among our patients was 9.3% as compared with 5.7% in patients with myocardial revascularizations without endarterectomy (p=0.003). Cause of death was related to acute myocardial infarction in 18 (54.55%) patients. The most significant risk factors for mortality identified were as follows: diabetes mellitus (p=0.001; odds ratio =7.168), left main disease (<0.001; 9.283), female sex (0.01; 3.111), acute myocardial infarction (0.02; 3.546), ejection fraction <35% (<0.001; 5.89), and previous myocardial revascularization (<0.001; 4.295). CONCLUSION: Coronary endarterectomy is related to higher mortality, and the risk factors involved are important elements of a poor outcome.

Transmyocardial laser revascularization. Early clinical experience.

OBJECTIVE: To analyze the initial clinical experience of transmyocardial laser revascularization (TMLR) in patients with severe diffuse coronary artery disease. METHODS: Between February, 1998 and February, 1999, 20 patients were submitted to TMLR at the Heart Institute (InCor), University of São Paulo Medical School, Brazil, isolated or in association with conventional coronary artery bypass graft (CABG). All patients had severe diffuse coronary artery disease, with angina functional class III/IV (Canadian Cardiovascular Society score) unresponsive to medical therapy. Fourteen patients were submitted to TMLR as the sole therapy, whereas 6 underwent concomitant CABG. Fifty per cent of the patients had either been previously submitted to a CABG or to a percutaneous transluminal coronary angioplasty (PTCA). Mean age was 60 years, ranging from 45 to 74 years. RESULTS: All patients had three-vessel disease, with normal or mildly impaired left ventricular global function. Follow-up ranged from 1 to 13 months (mean 6.6 months), with no postoperative short or long term mortality. There was significant symptom improvement after the procedure, with 85% of the patients free of angina, and the remaining 15% of the patients showing improvement in functional class, as well as in exercise tolerance. CONCLUSION: This novel technique can be considered a low risk alternative for a highly selected group of patients not suitable for conventional revascularization procedures.

Pregnancy rate and birth rate of calves from a large-scale IVF program using reverse-sorted semen in Bos indicus, Bos indicus-taurus, and Bos taurus cattle.

Obtaining sexed sperm from previously frozen doses (reverse-sorted semen [RSS]) provides an important advantage because of the possibility of using the semen of bulls with desired genetic attributes that have died or have become infertile but from whom frozen semen is available. We report the efficiency of RSS on the pregnancy rate and birth rate of calves in a large-scale program using ovum pick-up and in vitro embryo production (IVEP) from Bos indicus, Bos indicus-taurus, and Bos taurus cattle. From 645 ovum pick-up procedures (Holstein, Gir, and Nelore), 9438 viable oocytes were recovered. A dose of frozen semen (Holstein, Nelore, Brahman, Gir, and Braford) was thawed, and the sperm were sex-sorted and cooled for use in IVF. Additionally, IVF with sperm from three Holstein bulls with freeze-thawed, sex-sorted (RSS) or sex-sorted, freeze-thawed (control) was tested. A total of 2729 embryos were produced, exhibiting a mean blastocyst rate of 29%. Heifers and cows selected for adequate body condition, estrus, and health received 2404 embryos, and 60 days later, a 41% average pregnancy rate was observed. A total of 966 calves were born, and 910 were of a predetermined sex, with an average of 94% accuracy in determining the sex. Despite the lower blastocyst rate with freeze-thawed, sex-sorted semen compared with sex-sorted semen, (P < 0.05), the pregnancy rate (bull I, 45% vs. 40%; II, 35% vs. 50%; and III, 47% vs. 48% for RSS and control, respectively; P > 0.05) and sex-sorted efficiency (bull I, 93% vs. 98%; II, 96% vs. 94%; and III, 96% vs. 97% for RSS and control, respectively; P > 0.05) were similar for each of the three bulls regardless of the sperm type used in the IVF. The sexing of previously frozen semen, associated with IVEP, produces viable embryos with a pregnancy rate of up to 40%, and calves of the desired sex are born even if the paternal bull has acquired some infertility, died, or is located a long distance from the sexing laboratory. Furthermore, these data show the feasibility of the process even when used in a large-scale IVEP program.

Morphology of the spermatheca of Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) / Morfologia da espermateca de Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859)

Abstract Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) is a potential vector of Chagas's disease and the comprehension of its reproductive biology is an important tool to control this insect. In the reproductive tract of female insects, the spermatheca plays a crucial role storing male spermatozoa after mating. Whithin insects the spermatheca shows a wide morphological diversity and the analysis of this characteristic can contribute to understand the reproductive biology of the species. This study describes the histology and histochemistry of the spermatheca of T. lecticularia. Females have a pair of elongated spermathecal reservoirs without associated accessory gland. The reservoir opens into the common oviduct via a narrow muscular duct. The reservoir epithelium has single layer of columnar secretory cells. The control of the release of spermatozoa from the spermatheca occurs via the muscular duct. The anatomical features of the spermatheca of T. lecticularia resemble those described of other Reduviidae. However, the histological and histochemical features of spermatheca observed in T. lecticularia were important to explain the maintenance of the viability of the spermatozoa stored.

Resumo Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) é um potencial vetor da doença de Chagas e a compreensão de sua biologia reprodutiva é um importante fator para seu controle populacional. No aparelho reprodutor feminino dos insetos, a espermateca desempenha a importante funcão de armazenar os espermatozoides após cópula. Nos insetos, a espermateca apresenta uma ampla diversidade morfológica e a análise destas características pode contribuir com o entendimento da biologia reprodutiva das espécies. Este estudo descreve histológica e histoquimicamente a espermateca de T. lecticularia. As fêmeas tem um par de espermatecas alongadas sem glândulas acessórias associadas. O reservatório conecta-se ao oviduto comum através de um ducto muscular curto que controla a liberação dos espermatozoides. O epitélio do reservatório possui uma camada de células secretoras colunares. As características anatômicas da espermateca de T. lecticularia são semelhantes às encontradas em outros Reduviidae. Entretanto, as características histológicas e histoquímicas observadas na espermateca são importantes para explicar a manutenção da viabilidade dos espermatozoides armazenados.

Study of the comprehension of the scientific method by members of a university health research laboratory.

In Brazil, scientific research is carried out mainly at universities, where professors coordinate research projects with the active participation of undergraduate and graduate students. However, there is no formal program for the teaching/learning of the scientific method. The objective of the present study was to evaluate the comprehension of the scientific method by students of health sciences who participate in scientific projects in an academic research laboratory. An observational descriptive cross-sectional study was conducted using Edgar Morin complexity as theoretical reference. In a semi-structured interview, students were asked to solve an abstract logical puzzle - TanGram. The collected data were analyzed using the hermeneutic-dialectic analysis method proposed by Minayo and discussed in terms of the theoretical reference of complexity. The students' concept of the scientific method is limited to participation in projects, stressing the execution of practical procedures as opposed to scientific thinking. The solving of the TanGram puzzle revealed that the students had difficulties in understanding questions and activities focused on subjects and their processes. Objective answers, even when dealing with personal issues, were also reflected on the students' opinions about the characteristics of a successful researcher. Students' difficulties concerning these issues may affect their scientific performance and result in poorly designed experiments. This is a preliminary study that should be extended to other centers of scientific research.