Iatrogenic Thoracic Duct Injury via the Right Internal Jugular Vein: A Case Report.

Thoracic duct injury is a rare mechanical complication during the insertion of a central venous cannula via the left internal jugular vein. We report a case of thoracic duct injury during the insertion of a temporary pacing lead via the right internal jugular vein. A 92-year-old woman presented with third-degree atrioventricular block. Temporary ventricular pacing was attempted via the right internal jugular venous route, but a guidewire and sheath migrated into the vessel structure that was not directly connected to the right ventricle. Considering the characteristics of the fluid obtained from the vessel and the anatomical components of the mediastinum, a diagnosis of thoracic duct injury was made. The system inserted incorrectly was removed and a pacing lead was placed in the right ventricular apex through the right internal jugular vein. Her clinical course was uneventful without developing pneumothorax, hemothorax, or chylothorax, and 5 days later, a permanent pacemaker was implanted via the left subclavian venous route.

Jugular Venous Pressure Response to Inspiration for Risk Assessment of Heart Failure.

Simplifying jugular venous pressure (JVP), visibility of the right internal jugular vein above the right clavicle in the sitting position, has been proposed in the management of heart failure (HF) because of its convenience. However, this method may be undervalued for the detection of mildly to moderately increased JVP. Increased JVP on inspiration, known as Kussmaul sign, may be a useful physical finding in this condition. This study consisted of 138 patients who were admitted for the management of HF. Using this simple method, JVP was assessed at rest in the sitting position before discharge; its response to inspiration was also examined if no high JVP was noted at rest. The primary outcome was a composite of cardiac death and hospitalization for worsening HF. Among all the patients, 16 patients (12%) had high JVP at rest and another 16 patients (12%) had high JVP not at rest but on inspiration. During a follow-up period of 249 ± 182 days, a primary outcome event occurred in 63 patients (46%). The incidence of adverse cardiac events was higher in patients with a high JVP at rest (69%; hazard ratio 3.31, 95% confidence interval 1.64 to 6.67, p = 0.0009) and in patients with a high JVP on inspiration (56%; hazard ratio 2.18, 95% confidence interval 1.02 to 4.63, p = 0.043) than in patients without a high JVP in both conditions (41%). In conclusion, a high JVP not only at rest but also on inspiration was associated with a poor prognosis. The response of JVP to inspiration using this simple technique of physical examination may be a new approach in the management of HF.

Oxytocin variation and brain region-specific gene expression in a domesticated avian species.

The Bengalese finch was domesticated more than 250 years ago from the wild white-rumped munia (WRM). Similar to other domesticated species, Bengalese finches show a reduced fear response and have lower corticosterone levels, compared to WRMs. Bengalese finches and munias also have different song types. Since oxytocin (OT) has been found to be involved in stress coping and auditory processing, we tested whether the OT sequence and brain expression pattern and content differ in wild munias and domesticated Bengalese finches. We sequenced the OT from 10 wild munias and 11 Bengalese finches and identified intra-strain variability in both the untranslated and protein-coding regions of the sequence, with all the latter giving rise to synonymous mutations. Several of these changes fall in specific transcription factor-binding sites, and show either a conserved or a relaxed evolutionary trend in the avian lineage, and in vertebrates in general. Although in situ hybridization in several hypothalamic nuclei did not reveal significant differences in the number of cells expressing OT between the two strains, real-time quantitative PCR showed a significantly higher OT mRNA expression in the cerebrum of the Bengalese finches relative to munias, but a significantly lower expression in their diencephalon. Our study thus points to a brain region-specific pattern of neurochemical expression in domesticated and wild avian strains, which could be linked to domestication and the behavioral changes associated with it.

Surgical Removal of a Pacemaker Lead Entrapped by a Chiari Network: A Case Report.

The Chiari network, one of the remnants of the right valve of the sinus venosus, is considered clinically insignificant in most cases but attention should be paid since this embryological remnant can be a potential risk for complications during procedures. We report a case of atrioventricular block in which a pacemaker lead was entrapped by a Chiari network. A 78-year-old woman underwent dual-chamber pacemaker implantation for symptomatic 2:1 atrioventricular block. A tined J-shaped atrial lead was placed at the right atrial appendage, which later became dislodged to a lower position and entrapped. After multiple unsuccessful attempts to withdraw the lead, surgical removal was performed. The lead was strictly entangled within the fibrous threads of the Chiari network that was not detected by transthoracic echocardiography before and during the implantation.

A case of cardiac tamponade due to coronary artery injury caused by atrial screw-in lead.

A 74-year-old man who had a history of paroxysmal atrial fibrillation, visited the emergency department because of syncope. An electrocardiogram showed atrial fibrillation with slow ventricular response and long pauses. A permanent pacemaker was implanted under oral anticoagulation. Two screw-in leads were positioned at the right atrial appendage and the right ventricular apex. Seven hours after the implantation, he collapsed with hypotension due to cardiac tamponade. Vital signs improved after urgent pericardial drainage, but blood was continuously drained from the pericardial catheter. Due to uncontrollable cardiac tamponade, surgical repair was indicated. We found neither of the leads perforated the myocardium, but there was intermittent bleeding from a pin hole injury in the atrial wall site of the right coronary artery. Redness was observed in the right atrial appendage, but there was no bleeding point. We supposed that the screw tip of the atrial lead might have perforated the atrial appendage,　but was retracted spontaneously afterwards. The pin hole was closed with a patch and the postoperative course was uneventful. This is a rare case of cardiac tamponade due to the injury of the coronary artery by a screw-in lead positioned at the right atrial appendage. .

Clinical significance of rectus femoris diameter in heart failure patients.

Heart failure (HF) is often accompanied by skeletal muscle weakness and exercise intolerance, which are known as prognostic factors of HF. Comprehensive evaluation of physical function is important, but it is not commonly conducted because of the lack of equipment or appropriate expertise. Measurement of rectus femoris diameter (RFD) by ultrasound is convenient and noninvasive, but it has not been clarified that RFD could represent physical functions in HF patients. This study evaluated 185 consecutive HF patients and underwent assessment including RFD, grip power (GP), knee extension strength (KES), skeletal muscle index (SMI), nutrition status, cardiopulmonary exercise testing, and New York Heart Association (NYHA) functional class. RFD was related with NYHA class and significantly correlated with GP, KES, SMI, body mass index, pre-albumin level, geriatric nutritional risk index, and peak VO2 (r = 0.631, 0.676, 0.510, 0.568, 0.380, 0.539, 0.527, respectively; p < 0.001). Multivariate regression analysis revealed that estimated glomerular filtration rate (ß = 0.551) and RFD (ß = 0.326) were predictive factors of peak VO2. Gender, age, brain natriuretic peptide level, left ventricular ejection fraction, and hemoglobin level were the other explanatory parameters. The cut off value of RFD for sarcopenia diagnosis was estimated as 15 mm (sensitivity = 0.767 and specificity = 0.808). RFD is a simple and useful marker which reflects skeletal muscle strength/volume, exercise tolerance, nutrition status, and NYHA class. It is also associated with sarcopenia in HF patients.

Third and Fourth Heart Sounds and Myocardial Fibrosis in Hypertrophic Cardiomyopathy.

BACKGROUND: The 4th heart sound (S4) is commonly heard in patients with hypertrophic cardiomyopathy (HCM). The 3rd heart sound (S3) is also audible in HCM patients regardless of the presence or absence of heart failure. These extra heart sounds may be associated with myocardial fibrosis because myocardial fibrosis has been suggested to affect left ventricular compliance.Methods and Results:The present retrospective study evaluated 53 consecutive HCM patients with sinus rhythm who had no symptoms of heart failure and underwent an initial assessment including phonocardiography, echocardiography, and late gadolinium enhancement (LGE) magnetic resonance imaging (MRI). S3 was detected on phonocardiography in 13% of all patients, and S4 was recorded in 75% of patients. Patients with S3 had a higher incidence of LGE and larger LGE volumes (86% and 11.5±2.4 g/cm, respectively) than patients without S3 (33% and 2.5±0.8 g/cm, respectively; P=0.02 and P=0.002). The presence of S4 was not associated with MRI findings, including the incidence of LGE and LGE volume. The diagnostic value of S3 for the detection of LGE was highly specific (97%), with a low sensitivity (29%). CONCLUSIONS: Myocardial fibrosis, as assessed by LGE, was associated with S3 but not with S4 in patients with HCM. These results may contribute to the risk stratification of patients with HCM.

Hormonal Responses to a Potential Mate in Male Birds.

Social interactions rapidly modulate circulating hormone levels and behavioral patterns in most male animals. In male birds, sexual interaction or visual exposure to a conspecific female usually causes an increase in the levels of peripheral reproductive hormones, such as gonadotropins and androgens. Although the perception of a female presence is processed in the brain and peripheral hormonal levels are regulated by the hypothalamus-pituitary-gonadal (HPG) axis, the specific neural circuitry and neurochemical systems that translate social signals into reproductive physiology in male birds were not well understood until 2008. Today, there is growing evidence that two neuropeptides localized in the hypothalamus, gonadotropin-releasing hormone and gonadotropin-inhibitory hormone, are responsive to social information. These two neuropeptides have thus begun to be regarded as modulators translating social stimuli into changes in the levels of peripheral reproductive hormones. Here, we review previous studies that investigated the male responses of the HPG axis to the mere presence of a female or to sexual interaction, and describe the neurochemical pathways linking visual perception of a potential mate to rapid peripheral hormonal changes via the brain-pituitary endocrine system in sexually mature male Japanese quail.

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2012: General view of the pathogens' antibacterial susceptibility.

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from the patients in Japan was conducted by Japanese Society of Chemotherapy, Japanese association for infectious diseases and Japanese society for Clinical Microbiology in 2012. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period between January and December in 2012 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical Laboratory Standard Institutes. Susceptibility testing was evaluated in 1236 strains (232 Staphylococcus aureus, 225 Streptococcus pneumoniae, 16 Streptococcus pyogenes, 231 Haemophilus influenzae, 147 Moraxella catarrhalis, 167 Klebsiella pneumoniae and 218 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was 51.3%, and those of penicillin-intermediate S. pneumoniae was 0.4%. Among H. influenzae, 5.6% of them were found to be ß-lactamase-producing ampicillin-resistant strains, and 37.2% to be ß-lactamase-non-producing ampicillin-resistant strains. Extended spectrum ß-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo ß-lactamase were 4.2% and 3.2%, respectively. Continuous national surveillance is important to determine the actual situation of the resistance shown by bacterial respiratory pathogens to antimicrobial agents.

Comparative morphology of gonads from six species of fish belonging to the family Anostomidae (Characiformes: Anostomidae) / Morfología comparativa de las gónadas de seis especies de peces de la familia Anostomidae (Characiformes: Anostomidae)

AbstractIn fishes, gonad morphology is an important parameter to understand the reproductive biology, phylogenetic relationships and systematic studies. The main objective of this study was to make a comparative analysis of the morphology of mature ovary and testis in six fish species of the family Anostomidae. A total of 212 specimens, presenting maturing gonads, were captured from the São Francisco River, Três Marias Reservoir area, in Southeastern Brazil, between August 2008 and December 2010. The six analyzed species had mature ovaries and showed a grayish color. In vitellogenic oocytes (VO), cortical alveoli (CA) were composed by small vesicles in all Leporinus species, but in Leporellus vittatus and Schizodon knerii the CA were large vesicles. However, the CA of all species showed similar histochemical content. The pellucid zone consists of two layers to all species, but it was thicker in S. knerii (11.5 ± 1.8 µm) than in L. vittatus (9.0 ± 0.8 µm) and Leporinus species (3.5 ± 0.6 - 8.7 ± 0.9 µm). Follicular cells of the VO were respectively cubic and prismatic in animal and vegetative poles of S. knerii (22.3 ± 3.2 and 61.1 ± 9.6 µm), and squamous in the other species (1.3 ± 0.3 - 1.6 ± 0.3 µm). Females of S. knerii and males of L. vittatus showed lower values of gonadosomatic index (GSI) than the other assessed species. All evaluated species presented testicular morphology similar to most neotropical Characiformes, with unrestricted spermatogonial testis and anastomosing tubular organization of seminiferous tubules. Phenotypical differences in the vitellogenic oocyte of Anostomidae fishes, confirmed the taxonomic position of S. knerii as different genus in relation to Leporinus and L. vittatus. Despite being placed in different genera, the characteristics of the vitellogenic oocytes of L. vittatus were similar to those found in the studied Leporinus.

ResumenTeniendo en cuenta que la morfología de las gónadas es un parámetro importante para la comprensión de la biología de la reproducción, las relaciones filogenéticas y estudios sistemáticos, el objetivo principal de este estudio fue realizar un análisis comparativo de la morfología de ovarios maduros y testículos en seis especies de peces de la familia Anostomidae. Un total de 212 especímenes, con las gónadas en maduración, fueron capturados en el río São Francisco, área de embalse de Três Marias, en el sureste de Brasil, entre agosto 2008 y diciembre 2010. Las seis especies analizadas mostraron ovarios maduros de un color grisáceo. En los ovocitos vitelogénicos (VO), los alvéolos corticales (CA) están compuestos por pequeñas vesículas en todas las especies de Leporinus, pero en Leporellus vittatus y Schizodon knerii los CA son grandes vesículas. Los CA de todas las especies mostraron, no obstante, un contenido histoquímico similar. La zona pelucida se compone de dos capas en todas las especies, pero es más gruesa en S. knerii (11.5 ± 1.8 µm) que en L. vittatus (9.0 ± 0.8 µm) y las especies de Leporinus (3.5 ± 0.6 - 8.7 ± 0.9 µm). Las células foliculares de los VO son, cúbico y prismática en polos animales y vegetativos de S. knerii (22.3 ± 3.2 y 61.1 ± 9.6 µm), respectivamente, y escamosas en las otras especies (1.3 ± 0.3 - 1.6 ± 0.3 µm). Las hembras de S. knerii y los machos de L. vittatus mostraron menor GSI que las otras especies evaluadas. Todas las especies presentan una morfología testicular similar a la mayoría de los Characiformes neotropicales, los cuales poseen testículos espermatogonias sin restricciones y organización tubular anastomosis de los túbulos seminíferos. Las diferencias fenotípicas en los VO entre las especies de Anostomidae confirman la posición taxonómica de S. knerii como género diferente en relación a Leporinus y L. vittatus. A pesar de ser colocados en diferentes géneros, las características de los ovocitos vitelogénicos de L. vittatus son similares a los encontrados en los Leporinus estudiados.

Diastolic murmur in mid-ventricular obstructive hypertrophic cardiomyopathy: A case report.

A diastolic murmur is informative in the diagnosis of valvular heart disease, such as mitral stenosis and aortic regurgitation. Patients with hypertrophic cardiomyopathy (HCM) could have diastolic murmurs, although this is not widely recognized. We describe an illustrative case of HCM which was found to have a diastolic murmur associated with mid-left ventricular obstruction. An asymptomatic 65-year-old male was referred because of an abnormal electrocardiogram. Cardiac auscultation showed a soft fourth heart sound, a systolic ejection murmur, and a third heart sound followed by a diastolic murmur at the apex. On phonocardiography, the mid-diastolic murmur was predominantly low-pitched with an onset of about 200 ms after the second heart sound and a duration of approximately 150 ms. The timing of the diastolic murmur was consistent with an increased blood inflow during diastole in the mid-ventricular obstruction (2.0 m/s), which was produced by narrowing between the hypertrophied ventricular septum and the protrusion of the anterior papillary muscle. .

[Empathy to be Shown by Pharmacists toward Home Patients - Initiatives Undertaken by Pharmacists to Promote the Proper Use of Pharmaceutical Products].

Separation of medical and dispensary services has taken root in Japan as a healthcare system;8 00 million prescriptions have been issued, and 70% of medical institutions now participate in this practice. Additionally, discussions are ongoing regarding patient-oriented family pharmacies from a"back-to-basics"perspective of the separation drug dispensing from medical practice. Through a series of such discussions, the Ministry of Health, Labour and Welfare published a paper entitled"Vision for Pharmacies Working for Patients"with a focus on 3 functions to be implemented by family pharmacists and pharmacies. In home healthcare, there have been cases so far, as shown in the Vision paper, of suggestions from and initiatives taken by pharmacists that have helped improve patient home care services. This paper explores home care-related initiatives undertaken by our pharmacy, including 2 cases in which our pharmacists intervened to prevent duplicate prescriptions and promoted adherence to a medication regimen, having noticed a change in a patient's physical abilities caused by the presence of drug residues. Our pharmacists will inform other relevant professionals about this issue. The study discusses our experience, which may help provide insight on the ideal roles of pharmacists in this time of partnerships among professionals.

Unusual clinical course after surgical repair of unruptured aneurysm of sinus of Valsalva.

Aneurysms of the sinus of Valsalva are characterized by dilatation of at least one of the three aortic sinuses. We experienced a case with unruptured aneurysm of the right sinus of Valsalva, in which serial imaging studies were useful in assessing a rare complication after surgical repair. An asymptomatic 75-year-old man underwent patch closure of the aneurysm orifice because of progressive enlargement of the aneurysm. The postoperative course was uneventful, and computed tomography (CT), performed a week after the patch repair, showed no leakage of contrast medium into the isolated aneurysm. Three months later, echocardiography showed decreased size of the aneurysm with heterogeneous echogenicity and possible blood flow in the aneurysm, findings suggestive of thrombus formation and a recurrent fistula. CT with contrast medium showed partial recanalization between the patched aneurysm and the right sinus of Valsalva. Follow-up echocardiography, performed 1 year after surgery, revealed neither definite aneurysm nor shunt flow of Valsalva. The present case highlights that non-invasive follow-up can be an alternative option when carried out with caution in selected patients with incomplete closure of Valsalva aneurysm.

Comparative morphology of the oocyte surface and early development in four characiformes from the São Francisco River, Brazil.

Early development from the egg fertilization to complete resorption of the yolk-sac is a critical period in the life cycle of teleost fish. Knowledge of this process provides essential parameters for aquaculture and identification of spawning sites in the wild. In the present study, a comparative morphological analysis of the oocyte surface as well as early development was performed in four commercially valuable species from the São Francisco River: Brycon orthotaenia, Leporinus obtusidens, Prochilodus argenteus, and Salminus franciscanus. Stripped oocytes, embryo, and yolk-sac larvae were analyzed by scanning electron microscopy (SEM) and histology. A set of 10 lectins was used for investigation of lectin-binding pattern in oocytes. In the four species, the outer layer of the zona radiata reacted to most lectins, indicating complex polysaccharides at the oocyte surface while no reactivity was detected in the inner zona radiata and yolk globules. Typical structural arrangements were recognized at the micropylar region by SEM. The four species showed nonadhesive eggs, short embryonic period (18-20 h at 24 ± 1°C), and poorly developed larvae at hatching. At 24 h posthatching (hph), larvae of the four species had neuromasts on the body surface. Rudimentary cement glands for larval attachment were identified on the cephalic region at 24 and 48 hph in B. orthotaenia and S. franciscanus, and following they were in regression. The time for whole yolk resorption varied among species from 48 to 120 hph, occurring earlier in S. franciscanus, followed by B. orthotaenia, P. argenteus, and L. obtusidens. The formation of the digestive tract and the mouth opening indicated initiation of exogenous feeding 24 h before complete resorption of the yolk. Together, our data indicate similarities in the early development among species that may be related to the life cycle strategies and phylogeny.

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2010: General view of the pathogens' antibacterial susceptibility.

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from patients in Japan, was conducted by Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases and Japanese Society for Clinical Microbiology in 2010. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period from January and April 2010 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical and Laboratory Standard Institutes using maximum 45 antibacterial agents. Susceptibility testing was evaluable with 954 strains (206 Staphylococcus aureus, 189 Streptococcus pneumoniae, 4 Streptococcus pyogenes, 182 Haemophilus influenzae, 74 Moraxella catarrhalis, 139 Klebsiella pneumoniae and 160 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was as high as 50.5%, and those of penicillin-intermediate and -resistant S. pneumoniae were 1.1% and 0.0%, respectively. Among H. influenzae, 17.6% of them were found to be ß-lactamase-non-producing ampicillin (ABPC)-intermediately resistant, 33.5% to be ß-lactamase-non-producing ABPC-resistant and 11.0% to be ß-lactamase-producing ABPC-resistant strains. Extended spectrum ß-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo ß-lactamase were 2.9% and 0.6%, respectively. Continuous national surveillance of antimicrobial susceptibility of respiratory pathogens is crucial in order to monitor changing patterns of susceptibility and to be able to update treatment recommendations on a regular basis.

Notched QRS for the assessment of myocardial fibrosis in hypertrophic cardiomyopathy.

BACKGROUND: Patients with hypertrophic cardiomyopathy (HCM) sometimes develop myocardial fibrosis in association with adverse cardiovascular events. Electrocardiography (ECG) could provide helpful information on myocardial fibrosis in HCM, as in coronary artery disease. METHODS AND RESULTS: A total of 60 patients with HCM without bundle branch block underwent cardiac magnetic resonance imaging (CMR). The extent or location of late gadolinium enhancement (LGE) was examined in relation to 12-lead ECG. A notch on QRS was defined as at least 2 consecutive spikes in the same polarity with a reversal of direction ≥90° and the initial negative deflection ≥0.05 mV. LGE was associated with notched QRS, leftward QRS axis, and prolonged QRS duration, but not with any other findings such as abnormal Q waves, R-wave amplitude, or ST-T changes. Notched QRS was most useful in determining the presence or absence of myocardial fibrosis, with a sensitivity of 70% and a specificity of 81% using a cut-off of the number of leads with notched QRS ≥2. The number of notched QRS leads was positively correlated with LGE volume (P<0.01) and the lead distribution of notched QRS was informative about the location of LGE. CONCLUSIONS: A notch on QRS was useful in estimating myocardial fibrosis as assessed on CMR LGE in HCM patients without bundle branch block.

Sex-response differences of immunological and histopathological biomarkers in gill of Prochilodus argenteus from a polluted river in southeast Brazil.

The fish gill is in direct and standing contact with the immediate external environment and, therefore, is highly vulnerable to aquatic pollutants. In this study, Prochilodus argenteus were caught at two different points in São Francisco river. The first point is located near Três Marias dam, while the second is placed downstream the Abaeté river. Chemical approaches showed the presence of metals contamination in the first point. Thus, the main goal of this study was to investigate the possible toxic effects of these contaminants and the likely use of biomarkers on fish gills. Biometric data of length and weight of fish were obtained in order to calculate the condition factor as an organismal biomarker. The histological changes in gills and alterations in mucous and rodlet cells occurrence were detected microscopically and evaluated with quantitative analyses. Myeloperoxidase (MPO) and Eosinophil Peroxidase (EPO) were also assessed in fish gill. The analysis of the water and sediment samples revealed the presence of metals at the two points. As and Cd were detected at higher concentrations at point 1. The presence of lamellar cell hyperplasia, lamellar fusion, lamellar edema and inflammatory foci varied according to the point. Additionally, mucous and rodlet cells and MPO and EPO activities showed variability according to the environmental conditions. Furthermore, with exception of lamellar hyperplasia and eosinophil peroxidase activity, all others parameters showed sex-variation responses. At the first point, male fish showed a chronical inflammation in gills due to the lowest activity of MPO and EPO, as well as low occurrence of inflammatory foci and glycoprotein secretion by mucous cells, while female fish presented an opposite pattern of response to the same environmental conditions. Therefore, we suggest the use of such biomarkers in future monitoring of aquatic systems, taking into account the sex-variation responses.

Synergistic cooperation of PDI family members in peroxiredoxin 4-driven oxidative protein folding.

The mammalian endoplasmic reticulum (ER) harbors disulfide bond-generating enzymes, including Ero1α and peroxiredoxin 4 (Prx4), and nearly 20 members of the protein disulfide isomerase family (PDIs), which together constitute a suitable environment for oxidative protein folding. Here, we clarified the Prx4 preferential recognition of two PDI family proteins, P5 and ERp46, and the mode of interaction between Prx4 and P5 thioredoxin domain. Detailed analyses of oxidative folding catalyzed by the reconstituted Prx4-PDIs pathways demonstrated that, while P5 and ERp46 are dedicated to rapid, but promiscuous, disulfide introduction, PDI is an efficient proofreader of non-native disulfides. Remarkably, the Prx4-dependent formation of native disulfide bonds was accelerated when PDI was combined with ERp46 or P5, suggesting that PDIs work synergistically to increase the rate and fidelity of oxidative protein folding. Thus, the mammalian ER seems to contain highly systematized oxidative networks for the efficient production of large quantities of secretory proteins.

The roles of marginal lagoons in the maintenance of genetic diversity in the Brazilian migratory fishes Prochilodus argenteus and P. costatus

The rio São Francisco basin contains many endemic species, such as Prochilodus argenteus and P. costatus, which have great commercial importance. However, information about the main recruitment sites and genetic studies containing extensive sampling of these species are scarce. To investigate the roles of the marginal lagoons in the maintenance of genetic variability and in the population structure, we analyzed six microsatellite loci in nine sampling groups of P. argenteus and five sampling groups of P. costatus. Our results showed high levels of genetic variability and low values of genetic differentiation for P. argenteus (F ST = 0.008, P < 0.05) and for P. costatus (F ST = 0.031, P < 0.05). In addition, high values of gene flow combined with a small genetic distance suggest the presence of a single population for each species in the middle rio São Francisco basin. Moreover, putative migration routes involving marginal lagoons during the reproductive season could be detected, confirming the importance of these nurseries in the lifecycle of these species. Our results also indicate the necessity of adequate management of the fish resources and the conservation of the floodplains in the rio São Francisco basin.

A bacia do rio São Francisco contém muitas espécies endêmicas, tais como Prochilodus argenteus e P. costatus, os quais têm grande importância comercial. Entretanto, informações sobre as principais áreas de recrutamento e estudos genéticos contendo uma extensa amostragem dessas espécies no rio São Francisco são escassas. Para investigar o papel das lagoas marginais na manutenção da variabilidade genética e na estruturação populacional dessas espécies, nós analisamos seis loci microssatélites em nove grupos amostrais de P. argenteus e cinco grupos amostrais de P. costatus. Nossos resultados revelaram altos níveis de variabilidade genética para ambas as espécies e valores baixos de diferenciação genética para P. argenteus (F ST= 0.008, P < 0.05) e P. costatus (F ST= 0.031, P < 0.05). Adicionalmente, valores altos de fluxo gênico combinados com a distância genética baixa sugerem a presença de uma única população para cada espécie no médio rio São Francisco. Possíveis rotas migratórias envolvendo lagoas marginais durante o período reprodutivo puderam ser detectadas, confirmando a importância das lagoas marginais no ciclo de vida dessas espécies. Nossos resultados também indicaram a necessidade de um manejo adequado dos recursos pesqueiros e a conservação das várzeas na bacia do rio São Francisco.

Induced spawning and reproductive variables of the catfish Lophiosilurus alexandri Steindachner, 1876 (siluriformes: pseudopimelodidae)

Lophiosilurus alexandri is an endemic fish from the São Francisco River basin, Brazil. The aim of this study was to induce L. alexandri to spawn and to obtain data on several reproductive variables for this species. For induced spawning, adults were submitted to Cyprinus carpio pituitary homogenate (CPH). Nine of the 12 females (75%) responded positively to the treatment. The stripping of oocytes was performed 8.4 h after the second dose of CPH with the water temperature maintained at 26ºC. The number of stripped oocytes per gram of ova was 74 ± 5 oocytes g-1, and the mean oocyte diameter was 3.1 ± 0.2 and 3.6 ± 0.2 mm, before and after hydration, respectively. The oocytes were opaque, yellowish, demersal, highly adhesive, and covered by a gelatinous coat. The total fecundity was 4,534 ± 671 oocytes, and the fertilization rate was 59%. The initial and final fertilities were 2,631 ± 740 and 1,542 ± 416 embryos, respectively. Larval hatching occurred up to 56 h after fertilization, and the larvae had a total length of 8.4 ± 0.1 mm. This work provides important biological information for L. alexandri that can be used for management and conservation of this species.

Lophiosilurus alexandri é um peixe endêmico da bacia do rio São Francisco, Brasil. O objetivo do trabalho foi induzir L. alexandri à desova e obter dados sobre várias variáveis reprodutivas para esta espécie. Para desova induzida, adultos foram submetidos ao homogeneizado de hipófise de Cyprinus carpio (HHC). Nove das 12 fêmeas (75%) responderam positivamente ao tratamento. A extrusão dos ovócitos aconteceu 8,4 h após a segunda dose de HHC com a temperatura da água mantida a 26ºC. O número de ovócitos liberados por grama de ova foi de 74 ± 5 ovócitos g-1 e a média do diâmetro ovocitário foi de 3,1 ± 0,2 e 3,6 ± 0,2 mm, antes e depois da hidratação, respectivamente. Os ovócitos foram opacos, amarelo-castanho, demersais, altamente adesivos e revestidos por capa gelatinosa. A fecundidade total apresentou 4.534 ± 671 ovócitos e a taxa de fertilização foi de 59%. As fertilidades inicial e final foram de 2.631 ± 740 e 1.542 ± 416 embriões, respectivamente. A eclosão das larvas aconteceu até 56 h após a fertilização e as larvas tiveram comprimento total de 8,4 ± 0,1 mm. Este trabalho fornece informações biológicas importantes para L. alexandri, que podem ser utilizadas para o manejo e conservação desta espécie.