Cytogenetic study in sand spiders (Sicariidae) from the brazilian Caatinga: sex chromosome system diversity in closely related species / Estudio citogenético en arañas de arena (Sicariidae) de la Caatinga brasileña: diversidad del sistema de cromosomas sexuales en especies estrechamente relacionadas

ABSTRACT In this study, we investigated the chromosomes of three species of Sicarius spiders from the Brazilian Caatinga, using classical and molecular cytogenetic techniques. Based on the phylogenetic approach, we also discussed about the variation of diploid number, types of sex chromosome system and changes in the localization of ribosomal genes of Scytodoidea. Sicarius are Synspermiata spiders that together with the genera Loxosceles and Hexophthalma constitute the family Sicariidae. In this group, the available cytogenetic data showed a low diploid number range (2n♂=18 to 2n♂=23) and the presence of only multiple sex chromosome systems (X1X2Y and X1X20). Mitotic metaphase cells exhibited 2n♂=16+X1X2Y for Sicarius cariri and S. ornatus, and 2n♂=18+XY for S. tropicus. In these species, silver impregnation revealed nucleolar organizer region (Ag-NOR) on the terminal region of pair 1. In S. ornatus and S. tropicus, the results obtained with fluorescent in situ hybridization (FISH) using 18S rDNA probe were similar to Ag-NOR, however in S. cariri, the ribosomal sites were localized in the terminal region of the X1 sex chromosome. In this work, we presented the first description of a simple sex chromosome system for Sicariidae, helping to understand how the XY sex chromosome system evolved from the X1X2Y system. Additionally, FISH data incongruous with Ag-NOR indicate that the cytogenetic studies in Sicariidae allow investigating the relation between the karyotype evolution and the distribution and the activity of rDNA genes.

RESUMEN En este estudio, investigamos los cromosomas de tres especies de arañas Sicarius de la Caatinga brasileña, utilizando técnicas de citogenética clásica y molecular. Usando un enfoque filogenético, también discutimos la variación del número diploide, los tipos de sistema cromosómico sexual y los cambios en la localización de los genes ribosómicos en Scytodoidea. Los Sicarius son arañas Synspermiata que, junto con los géneros Loxosceles y Hexophthalma, constituyen a la familia Sicariidae. En este grupo, los datos citogenéticos disponibles mostraron un rango de número diploide bajo (2n♂=18 a 2n♂=23) y únicamente la presencia de sistemas de cromosomas sexuales múltiples (X1X2Y y X1X20). Las células mitóticas en metafase mostraron 2n♂=16+X1X2Y para Sicarius cariri y S. ornatus, y 2n♂=18+XY para S. tropicus. En estas especies, la impregnación de plata reveló la región organizadora nucleolar (Ag-NOR) en la región terminal del par 1. En S. ornatus y S. tropicus, los resultados obtenidos con la hibridación in situ fluorescente (FISH) utilizando la sonda de ADNr 18S fueron similares a los de Ag-NOR, sin embargo, en S. cariri los sitios ribosomales se localizaron en la región terminal del cromosoma sexual X1. En este trabajo, presentamos la primera descripción de un sistema cromosómico sexual simple para Sicariidae, ayudando a entender cómo el sistema cromosómico sexual XY evolucionó a partir del sistema X1X2Y. Además, los datos de FISH incongruentes con Ag-NOR indican que los estudios citogenéticos en Sicariidae permiten investigar la relación entre la evolución del cariotipo y la distribución y la actividad de los genes de ADNr.

Effective secondary fracture prevention: implementation of a global benchmarking of clinical quality using the IOF Capture the Fracture® Best Practice Framework tool.

UNLABELLED: Fracture Liaison Services are the best model to prevent secondary fractures. The International Osteoporosis Foundation developed a Best Practice Framework to provide a quality benchmark. After a year of implementation, we confirmed that a single framework with set criteria is able to benchmark services across healthcare systems worldwide. INTRODUCTION: Despite evidence for the clinical effectiveness of secondary fracture prevention, translation in the real-world setting remains disappointing. Where implemented, a wide variety of service models are used to deliver effective secondary fracture prevention. To support use of effective models of care across the globe, the International Osteoporosis Foundation's Capture the Fracture® programme developed a Best Practice Framework (BPF) tool of criteria and standards to provide a quality benchmark. We now report findings after the first 12 months of implementation. METHODS: A questionnaire for the BPF was created and made available to institutions on the Capture the Fracture website. Responses from institutions were used to assign gold, silver, bronze or black (insufficient) level of achievements mapped across five domains. Through an interactive process with the institution, a final score was determined and published on the Capture the Fracture website Fracture Liaison Service (FLS) map. RESULTS: Sixty hospitals across six continents submitted their questionnaires. The hospitals served populations from 20,000 to 15 million and were a mix of private and publicly funded. Each FLS managed 146 to 6200 fragility fracture patients per year with a total of 55,160 patients across all sites. Overall, 27 hospitals scored gold, 23 silver and 10 bronze. The pathway for the hip fracture patients had the highest proportion of gold grading while vertebral fracture the lowest. CONCLUSION: In the first 12 months, we have successfully tested the BPF tool in a range of health settings across the globe. Initial findings confirm a significant heterogeneity in service provision and highlight the importance of a global approach to ensure high quality secondary fracture prevention services.

Chromosomal characteristics of a Brazilian whip spider (Amblypygi) and evolutionary relationships with other arachnid orders.

We analyzed mitotic and meiotic cells of a Brazilian amblypygid, Heterophrynus longicornis, using conventional and molecular cytogenetic techniques (Giemsa staining, C-banding, Ag-NOR, and FISH with rDNA probe). This is the first study that focuses solely on amblypygid chromosomes; it was undertaken to add data on cytogenetic knowledge of this group and contribute to the understanding of chromosome evolution in the Arachnida. We found 2n = 66 for male and female individuals, monocentric chromosomes, and absence of morphologically differentiated sex chromosomes. C-banding showed heterochromatin in the pericentromeric region of most chromosomes. Mitotic and meiotic nuclei submitted to silver impregnation and FISH revealed, respectively, Ag-NORs and ribosomal genes in the terminal region of two chromosome pairs. Most chromosome features that we observed in H. longicornis are shared with species of other arachnid orders; however, the absence of morphologically differentiated sex chromosomes in amblypygid contrasts with the remarkable variety of sex chromosome systems recorded for the Araneae. Consequently, we conclude that analysis of species of the Tetrapulmonata clade is useful for understanding the trends of sex chromosome evolution in this arachnid group.

Chromosomal characteristics and karyotype evolution of Oxyopidae spiders (Araneae, Entelegynae).

We made a cytogenetic analysis of four species of Oxyopidae and compared it with the karyotype data of all species of this family. In Hamataliwa sp, the mitotic cells showed 2n♂ = 26+X(1)X(2) and telocentric chromosomes. The 2n♂ = 28, which has been described for only one oxyopid spider, is the highest diploid number reported for this family. Peucetia species exhibited distinct karyotype characteristics, i.e., 2n♂ = 20+X(1)X(2) in P. flava and 2n♂ = 20+X in P. rubrolineata, revealing interspecific chromosome variability within this genus. However, both Peucetia species exhibited telocentric chromosomes. The most unexpected karyotype was encountered in Oxyopes salticus, which presented 2n♂ = 10+X in most individuals and a predominance of biarmed chromosomes. Additionally, one male of the sample of O. salticus was heterozygous for a centric fusion that originated the first chromosomal pair and exhibited one supernumerary chromosome in some cells. Testicular nuclei of Hamataliwa sp and O. salticus revealed NORs on autosomal pairs, after silver impregnation. The majority of Oxyopidae spiders have their karyotype differentiated by both reduction in diploid number chromosome number and change of the sex chromosome system to X type; however, certain species retain the ancestral chromosome constitution 2n = 26+X1X2. The most remarkable karyotype differentiation occurred in O. salticus studied here, which showed the lowest diploid number ever observed in Oxyopidae and the second lowest registered for Entelegynae spiders.

Chromosomal characteristics and karyotype evolution of Oxyopidae spiders (Araneae, Entelegynae)

number chromosome number and change of the sex chromosomesystem to X type; however, certain species retain the ancestralchromosome constitution 2n = 26+X1X2. The most remarkablekaryotype differentiation occurred in O. salticus studied here, whichshowed the lowest diploid number ever observed in Oxyopidae andthe second lowest registered for Entelegynae spiders.

Intriguing evidence of translocations in Discus fish (Symphysodon, Cichlidae) and a report of the largest meiotic chromosomal chain observed in vertebrates.

As part of a program to understand the genetics of Amazonian ornamental fish, classical cytogenetics was used to analyze Symphysodon aequifasciatus, S. discus and S. haraldi, popular and expensive aquarium fishes that are endemic to the Amazon basin. Mitotic analyses in Symphysodon have shown some odd patterns compared with other Neotropical cichlids. We have confirmed that Symphysodon species are characterized by chromosomal diversity and meiotic complexity despite the fact that species share the same diploid number 2n=60. An intriguing meiotic chromosomal chain, with up to 20 elements during diplotene/diakinesis, was observed in S. aequifasciatus and S. haraldi, whereas S. discus only contains typical bivalent chromosomes. Such chromosomal chains with a high number of elements have not been observed in any other vertebrates. We showed that the meiotic chromosomal chain was not sex related. This observation is unusual and we propose that the origin of meiotic multiples in males and females is based on a series of translocations that involved heterochromatic regions after hybridization of ancestor wild Discus species.

Maternal expectations and birth-related experiences: a survey of pregnant women of mixed parity from Calcutta, India.

BACKGROUND: In India, as in other parts of the world with high birthrates, there is an imbalance between maternal expectations and provision of labor pain services. Maternal experience may have an impact on attitudes toward the mode of future deliveries and on cesarean section rates. Maternal expectations regarding labor and delivery, and attitudes towards cesarean section were assessed in women of mixed parity during an antenatal visit at a charitable non-governmental hospital in Calcutta. METHODS: Structured interviews based on a questionnaire were conducted with 205 women. RESULTS: The majority of the 205 women were nulliparous (71%); the average previous cesarean section rate among the parous minority (29%) was 38.8%. Expectation of labor pain was very common. In the absence of an idea of its severity (78%), a majority were ready to tolerate it as a natural phenomenon (71%). For most interviewees, information about epidural labor analgesia was new (97%), although they were prepared to ask for effective pain relief (98%) and pay for epidural analgesia, if available (95%). Nearly a quarter (24%) of subjects considered cesarean section as an option to avoid labor pain, while most (99%) perceived cesarean section to be safer for the baby than vaginal delivery. CONCLUSIONS: This study indicates that information on what to expect during labor and delivery, the potential role of epidural labor analgesia, and the impact of cesarean section on neonatal outcome should be the focus of services instituted to improve antenatal and perinatal care.

Mesabolivar brasiliensis (Moenkhaus 1898) and Mesabolivar cyaneotaeniatus (Keyserling 1891) (Araneomorphae, Pholcidae) Close relationship reinforced by cytogenetic analyses

Pholcidae is the most diverse family among haplogyne spiders but only 15 species have been analyzed cytogenetically. These studies revealed that the diploid number varies from 2n = 15 to 2n = 32, that there are three types of sex chromosome systems in males (X, X1X2 and X 1X2Y), and that the chromosomes are predominantly biarmed. Within the genus Mesabolivar, only Mesabolivar luteus (Keyserling 1891) has been karyotyped, and it showed 2n = 15 = 14 + X, with all chromosomes being metacentric. In the present work, we characterize the mitotic and meiotic chromosomes of Mesabolivar brasiliensis (Moenkhaus 1898) and Mesabolivar cyaneotaeniatus (Keyserling 1891). Male mitotic metaphases of the two species showed the diploid number 2n = 17= 16 + X; oogonial cells of M. brasiliensis showed 2n = 18= 16 + XX. In both species, the chromosomes were exclusively biarmed, and the X chromosome was the largest element of the karyotype. Diplotene spermatocytes of the two species exhibited 8II + X and the occurrence of only one terminal or interstitial chiasma per bivalent. In M. cyaneotaeniaus, metaphases II with n = 9 = 8 + X and n = 8 were found, indicating the regular segregation of all chromosomes during meiosis I. Mitotic metaphases of M. brasiliensis stained with CMA3/DA/DAPI revealed GC-rich chromatin in the terminal region of almost all autosomes, especially in pair 2. An earlier revision of the New World pholcids grouped M. brasiliensis and M. cyaneotaeniatus in a "southern group" and placed M. luteus in a "miscellaneous group." A molecular study showed a closer relationship between M. brasiliensis and M. cyaneotaeniatus than between M. luteus and either of these two species. The 2n = 17 found in M. brasiliensis and M. cyaneotaeniatus corroborates this hypothesis, given that M. luteus has a diploid number of 2n = 15.

Oral misoprostol vs. intravenous oxytocin in reducing blood loss after emergency cesarean delivery.

OBJECTIVE: To compare the effectiveness of oral misoprostol and intravenous oxytocin in reducing blood loss in women undergoing indicated or elective cesarean delivery (CD) under spinal anesthesia. METHODS: In this prospective, double-blind pilot study, 56 parturients who received 5 IU of intravenous oxytocin after cord clamping were randomized to further receive either misoprostol orally and a placebo infusion intravenously or placebo orally and an oxytocin infusion intravenously. RESULTS: After adjustment was made for the sonographically estimated amniotic fluid volume, there was no statistical difference in blood loss between the 2 groups (mean+/-S.D., 1083+/-920 mL in the oxytocin group vs. 970+/-560 mL in the misoprostol group; P=.59). CONCLUSION: Oxytocin followed by oral misoprostol is as effective as an oxytocin injection followed by an oxytocin infusion in reducing postoperative blood loss after CD, and the protocol may be a safe, valuable, and cost-effective alternative to oxytocin alone. Visual estimation of intraoperative blood loss undervalues the effective value of misoprostol use by 30%.

Ropivacaine versus bupivacaine 0.125% with fentanyl 1 microg/ml for epidural labour analgesia: is daily practice more important than pharmaceutical choice?

UNLABELLED: Ropivacaine might be superior to bupivcaine for epidural labour analgesia because it appears to induce less lower extremity motor blockade. The clinical relevance of this difference is not yet clear. METHODS: In a double-blind randomised trial bupivacaine and ropivacaine each at 0.125% with 1 microg/ml fentanyl were compared for epidural labour analgesia. This study was performed in two university hospitals. RESULTS: Sixty-three nulliparous women with singleton pregnancies at term were included. There were no differences between bupivacaine and ropivacaine as far as motor blockade, analgesic outcome, mode of delivery and neonatal outcome are concerned. However, the clinical management of epidural analgesia differed significantly between the two institutions involved. Parturients of one institution had their epidural catheter placed earlier, needed less top-up medication, and had more successful mobilisations, when compared to the other institution. CONCLUSIONS: Institutional clinical practice can be significantly different. Pharmacological differences between bupivacaine and ropivacaine at 0.125% with 1 microg/ml fentanyl seem to be less important than differences between institutions in terms of clinical practice.

Impact of spinal anaesthesia on peri-operative lung volumes in obese and morbidly obese female patients.

Although obesity predisposes to postoperative pulmonary complications, data on the relationship between body mass index (BMI) and peri-operative respiratory performance are limited. We prospectively studied the impact of spinal anaesthesia, obesity and vaginal surgery on lung volumes measured by spirometry in 28 patients with BMI 30-40 kg.m(-2) and in 13 patients with BMI > or = 40 kg.m(-2). Vital capacity, forced vital capacity, forced expiratory volume in 1 s, mid-expiratory and peak expiratory flows were measured during the pre-operative visit (baseline), after effective spinal anaesthesia with premedication, and after the operation at 20 min, 1 h, 2 h, and 3 h (after mobilisation). Spinal anaesthesia and premedication were associated with a significant decrease in spirometric parameters. Spinal anaesthesia and premedication were associated with a significant decrease in spirometric parameters; mean (SD) vital capacities were - 19% (6.4) in patients with BMI 30-40 kg.m(-2) and - 33% (9.0) in patients with BMI > 40 kg.m(-2). The decrease of lung volumes remained constant for 2 h, whereas 3 h after the operation and after mobilisation, spirometric parameters significantly improved in all patients. This study showed that both spinal anaesthesia and obesity significantly impaired peri-operative respiratory function.

Comparison of perioperative spirometric data following spinal or general anaesthesia in normal-weight and overweight gynaecological patients.

BACKGROUND: There is limited data comparing the impact of spinal anaesthesia (SA) and general anaesthesia (GA) on perioperative lung function. Here we assessed the differences of these two anaesthetic techniques on perioperative lung volumes in normal-weight (BMI < 25) and overweight (BMI 25-30) patients using spirometry. METHODS: We prospectively studied 84 consenting patients having operations in the vaginal region receiving either GA (n = 41) or SA (n = 43). Both groups (GA and SA) were further divided into two subgroups each (normal-weight vs. overweight). We measured vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), midexpiratory (MEF25-75) and peak expiratory flow rates (PEFR) at the preoperative assessment (baseline), after premedication, after effective SA, and 20 min, 1 h, 2 h and 3 h after the operation (last measurement after patient mobilization). RESULTS: Premedication was associated with a small but significant decrease in lung volumes in direct correlation with BMI (-5%). Spinal anaesthesia resulted in a significant reduction in lung volumes in overweight as opposed to normal-weight patients. Postoperatively, lung volumes were significantly more reduced following GA than SA as indicated by differences in mean VC (SD) of -12 (6)% vs. -6 (5)% 20 min after the end of the operation in the normal-weight and -18 (5)% vs. -10 (5)% in the overweight patients. There was a significant impact of BMI on postoperative respiratory function, which was significantly more important in the GA group than in the SA group, and recovery of lung volumes was more rapid in the normal-weight patients than in the overweight patients, particularly in the SA group. CONCLUSION: In gynaecological patients undergoing vaginal surgery, the impact of anaesthesia on postoperative lung function as assessed by spirometry was significantly less after SA than GA, particularly in overweight patients.

Overview of rabies in the Americas.

Between 1993 and 2002, the number of human and canine rabies cases in the Americas Region fell by approximately 80%. There were 39 human cases in 2002, 63% of them transmitted by dogs. Furthermore, human rabies transmitted by wildlife, mostly by bats is a risk to inhabitants in many countries in the Region. The objective of this study is to describe this epidemiological situation based in the information received from the countries of the Americas Region in Regional Rabies Surveillance System in the Americas (SIRVERA) administrated by the Pan American Health Organization. This sharp reduction is attributable mainly to the control measures implemented by the countries of the Region, such as the mass vaccination of dogs and prophylactic treatment for people who have been exposed.

Effect of obesity and thoracic epidural analgesia on perioperative spirometry.

BACKGROUND: Lung volumes in obese patients are reduced significantly in the postoperative period. As the effect of different analgesic regimes on perioperative spirometric tests in obese patients has not yet been studied, we investigated the effect of thoracic epidural analgesia and conventional opioid-based analgesia on perioperative lung volumes measured by spirometry. METHODS: Eighty-four patients having midline laparotomy for gynaecological procedures successfully completed the study. Premedication, anaesthesia and analgesia were standardized. The patients were given a free choice between epidural analgesia (EDA) (n=42) or opioids (n=42) for postoperative analgesia. We performed spirometry to measure vital capacity (VC), forced vital capacity, peak expiratory flow, mid-expiratory flow and forced expiratory volume in 1 s at preoperative assessment, 30-60 min after premedication and 20 min, 1 h, 3 h and 6 h after extubation. RESULTS: Baseline values were all within the normal range. All perioperative spirometric values decreased significantly with increasing body mass index (BMI). The greatest reduction in VC occurred directly after extubation, but was less in the EDA group than in the opioid group: mean of -23(sd 8)% versus -30(12)% (P<0.001). In obese patients (BMI>30) the difference in VC was significantly more pronounced than in patients of normal weight (BMI<25): -45(10)% versus -33(4)% (P<0.001). Recovery of spirometric values was significantly quicker in patients receiving EDA, particularly in obese patients. CONCLUSION: We conclude that EDA should be considered in obese patients undergoing midline laparotomy to improve postoperative spirometry.