Environmental impact on visual perception modulates behavioral responses of schooling fish to looming predators.

Aggregation in social fishes has evolved to improve safety from predators. The individual interaction mechanisms that govern collective behavior are determined by the sensory systems that translate environmental information into behavior. In dynamic environments, shifts in conditions impede effective visual sensory perception in fish schools, and may induce changes in the collective response. Here, we consider whether environmental conditions that affect visual contrast modulate the collective response of schools to looming predators. By using a virtual environment to simulate four contrast levels, we tested whether the collective state of minnow fish schools was modified in response to a looming optical stimulus. Our results indicate that fish swam slower and were less polarized in lower contrast conditions. Additionally, schooling metrics known to be regulated by non-visual sensory systems tended to correlate better when contrast decreased. Over the course of the escape response, schools remained tightly formed and retained the capability of transferring social information. We propose that when visual perception is compromised, the interaction rules governing collective behavior are likely to be modified to prioritize ancillary sensory information crucial to maximizing chance of escape. Our results imply that multiple sensory systems can integrate to control collective behavior in environments with unreliable visual information.

A visual horizon affects steering responses during flight in fruit flies.

To navigate well through three-dimensional environments, animals must in some way gauge the distances to objects and features around them. Humans use a variety of visual cues to do this, but insects, with their small size and rigid eyes, are constrained to a more limited range of possible depth cues. For example, insects attend to relative image motion when they move, but cannot change the optical power of their eyes to estimate distance. On clear days, the horizon is one of the most salient visual features in nature, offering clues about orientation, altitude and, for humans, distance to objects. We set out to determine whether flying fruit flies treat moving features as farther off when they are near the horizon. Tethered flies respond strongly to moving images they perceive as close. We measured the strength of steering responses while independently varying the elevation of moving stimuli and the elevation of a virtual horizon. We found responses to vertical bars are increased by negative elevations of their bases relative to the horizon, closely correlated with the inverse of apparent distance. In other words, a bar that dips far below the horizon elicits a strong response, consistent with using the horizon as a depth cue. Wide-field motion also had an enhanced effect below the horizon, but this was only prevalent when flies were additionally motivated with hunger. These responses may help flies tune behaviors to nearby objects and features when they are too far off for motion parallax.

Cytoreductive radical prostatectomy versus no local treatment in patients with metastatic prostate cancer.

Introduction: Prostate cancer is one of the most frequent cancers in Chile, with 8157 new cases in 2020. Worldwide, 5 to 10% of men have metastatic disease at diagnosis, and androgen deprivation therapy with or without chemotherapy is the standard of care for these patients. The use of local treatment in this setting has no formal recommendation due to the lack of high-quality evidence. Some retrospective studies have sought to elucidate the benefit of surgery on the primary tumor in the setting of metastatic disease since it has been proven to be an effective local treatment for other metastatic malignant diseases. Despite these efforts, the benefit of cytoreductive radical prostatectomy as local treatment in these patients remains unclear. Methods: We searched Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, and Cochrane, among others. We extracted data from systematic reviews, reanalyzed data from primary studies, conducted a meta-analysis, and generated a summary results table using the GRADE approach. Results and conclusions: We identified 12 systematic reviews, including seven studies in total, none of which was a trial. Only six of those seven primary studies were used in the results summary. Despite the lack of high-quality evidence, the results summary shows the benefits of performing surgery on the primary tumor in terms of all-cause mortality, cancer-specific mortality, and disease progression. There was also a potential benefit in local complications related to the progression of the primary tumor, supporting the implementation of this intervention in patients with metastatic disease. The absence of formal recommendations highlights the need to evaluate the benefits of surgery on a case-by-case basis, presenting the available evidence to patients for a shared decision-making process and considering future local complications that could be difficult to manage.

Psychological Health Status of Psychiatric Patients Living in Treatment Communities before and during the COVID-19 Lockdown: A Brief Report.

Many studies investigated the psychological impact of lockdown measures on the general population, while few studies focused on the psychiatric population. This study aimed to investigate the role of therapeutic communities in the management and containment of symptoms of patients with psychosis living in psychiatric residential facilities. Data were collected at two different points: November 2019 (Coronavirus disease 19 had not yet spread) and April 2020 (during the lockdown in Italy). Twenty-two study participants were recruited from three residential accredited psychiatric facilities. During lockdown, the patients showed a small increase in symptomatology in terms of emotional isolation. In addition, it was been observed significant differences in certain functional areas of the behavior, measured as lower inclination towards violent behaviors during lockdown, and higher scores in substance abuse and medical impairment. The lockdown condition could represent a form of containment; daily routines, along with adequate social support, are important aspects of the stability and the level of behavioral functioning of psychiatric patients. Social support and continuity of care offered by psychiatric communities can be an effective safeguard against the psychological impact of the COVID-19 epidemic.

Structure and property based design of factor Xa inhibitors: pyrrolidin-2-ones with monoaryl P4 motifs.

Structure and property based drug design was exploited in the synthesis of sulfonamidopyrrolidin-2-one-based factor Xa inhibitors, incorporating neutral and basic monoaryl P4 groups, ultimately producing potent inhibitors with effective levels of anticoagulant activity and extended oral pharmacokinetic profiles. However, time dependant inhibition of Cytochrome P450 3A4 was a particular issue with this series.

[Perioperative management of paragangliomas and pheochromocytomas]. / Manejo perioperatorio de feocromocitoma y paraganglioma.

Pheochromocytomas and paragangliomas are rare neuroendocrine tumors, characterized by a high morbidity rate due to catecholamine excess. These high levels are independent of physiologic stressors. For the diagnosis, a biochemical workup is paramount. The most widely used are plasma-free metanephrines and urinary fractionated metanephrines. Imaging studies should be initiated once the biochemical diagnosis is established. Evaluation of the patient with pheochromocytomas and paragangliomas must be done taking into account the leading causes of perioperative morbidity and mortality. The two primary interventions that have reduced perioperative mortality are alpha-adrenergic blockade and intravascular volume normalization. Another significant advance has been the establishment of laparoscopic surgery as the gold standard for the surgical approach. No anesthetic technique has been found to be superior to another. Intraoperative hemodynamic instability has been correlated with poorer outcomes; thus one of the main intraoperative goals is maintaining hemodynamic stability. Lower morbidity and almost zero mortality rates due to preoperative and intraoperative management improvements have led to a focus on the immediate and long-term postoperative care. Anual lifelong follow-up is recommended to detect recurrent disease.

Los feocromocitomas y paragangliomas son tumores neuroendocrinos raros, caracterizados por una alta tasa de morbilidad debida a un exceso de niveles de catecolaminas. Este exceso de catecolaminas es independiente de los estresores fisiológicos. Para el diagnóstico de un feocromocitoma-paraganglioma son fundamentales las pruebas bioquímicas. Las más utilizadas son las metanefrinas fraccionadas urinarias o metanefrinas libres plasmáticas. Seguido del diagnóstico bioquímico, debe realizarse un estudio imagenológico. La evaluación del paciente con diagnóstico de feocromocitoma-paraganglioma debe realizarse teniendo presente sus principales causas de morbimortalidad perioperatoria. Las dos grandes intervenciones que han disminuido la mortalidad perioperatoria son la introducción del α bloqueo y la restauración de la volemia. El otro gran avance ha sido la introducción de la cirugía laparoscópica como el estándar de oro para el abordaje quirúrgico. En relación con el manejo intraoperatorio, no se ha identificado que alguna técnica anestésica sea superior a otra. Sí se ha logrado establecer criterios de inestabilidad hemodinámica que se correlacionan con mayor morbilidad, por lo que los principales objetivos intraoperatorios son mantener estabilidad hemodinámica. El avance en el manejo preoperatorio e intraoperatorio con la consecuente disminución en la mortalidad relacionada a esta patología ha llevado el foco al manejo postoperatorio tanto agudo como a largo plazo. También se debe considerar el riesgo de recurrencia tumoral, por lo que estos pacientes deben tener un control anual de por vida.

Xanthogranulomatous orchitis: case report of a rare condition.

Xanthogranulomatous orchitis is a rare, non-neoplastic inflammatory condition. We present a case of a 55-year-old diabetic male with an increase in volume, pain and edema in right testicle with a one-year history. The examination involved the investigation of inflammatory markers and ultrasound. Exploration of the scrotum revealed important destruction of the tissue architecture. This case underscores the importance of including xanthogranulomatous orchitis in the differential diagnosis of a testicular lump.

Structure and property based design of factor Xa inhibitors: biaryl pyrrolidin-2-ones incorporating basic heterocyclic motifs.

Structure and property based drug design was exploited in the synthesis of sulfonamidopyrrolidin-2-one-based factor Xa (fXa) inhibitors, incorporating basic biaryl P4 groups, producing highly potent inhibitors with significant anticoagulant activities and encouraging oral pharmacokinetic profiles.

Structure and property based design of factor Xa inhibitors: pyrrolidin-2-ones with biaryl P4 motifs.

Structure and property based drug design was exploited in the synthesis of sulfonamidopyrrolidin-2-one-based factor Xa (fXa) inhibitors, incorporating biaryl P4 groups, producing highly potent inhibitors with encouraging oral pharmacokinetic profiles and significant but sub-optimal anticoagulant activities.

Laparoscopic repair of an iliac artery injury during radical cystoprostatectomy.

Laparoscopy has experienced significant growth in the last 5 years and became more popular among practicing urologists. Even though laparoscopy is considered a safe technique it is not free of complications, some of which can be devastating. Vascular injuries are the second most frequent complication during laparoscopic surgery with a reported incidence of 0.22% to 1.1%. With the standardization of surgical techniques and the increasing proficiency of the teams performing it, serious surgical complications may be corrected without the need for conversion. We report a case in which the right external iliac artery was injured while pelvic lymph node dissection was carried out before a planned laparoscopic radical cystoprostatectomy. The complication was successfully managed entirely by means of laparoscopy.

Prostatectomía radical citorreductora comparado a no realizar tratamiento local en pacientes con cáncer de próstata metastásico / Cytoreductive radical prostatectomy versus no local treatment in patients with metastatic prostate cancer

Introducción El cáncer de próstata es uno de los cánceres más frecuentes en Chile, con 8157 nuevos casos en 2020. A nivel mundial, 5 a 10% de los hombres presentan metástasis al diagnóstico, y la terapia de deprivación androgénica con o sin quimioterapia es el estándar de cuidado para estos pacientes. El uso de tratamiento local en este contexto tiene una recomendación formal debido a la falta de evi-dencia de alta calidad. Algunos estudios retrospectivos han intentado dilucidar el beneficio de la cirugía sobre el tumor primario en el contexto de la enfermedad metastásica, ya que se ha demostrado que es un tratamiento local eficaz para otras neoplasias metastá-sicas. A pesar de estos esfuerzos, el beneficio de la prostatectomía radical citorreductora como tratamiento local en estos pacientes sigue sin estar claro. Métodos Se realizó una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, que se mantiene mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE y Cochrane, entre otras. Se extrajeron los datos de las revisiones sistemáticas, se volvieron a analizar los datos de los estudios primarios, se realizó un metanálisis y se generó una tabla de resumen de resultados utilizando el enfoque GRADE. Resultados y conclusiones Se identificaron 12 revisiones sistemáticas, que incluían siete estudios primarios en total, ninguno de los cuales era un ensayo alea-torizado controlado. Sólo seis de esos siete estudios primarios se utilizaron en el resumen de resultados. A pesar de la falta de evi-dencia de alta calidad, los resultados de este resumen muestran los beneficios de realizar la cirugía en el tumor primario en términos de mortalidad por cualquier causas, mortalidad específica por cáncer y progresión de la enfermedad. También se observó un bene-ficio potencial en las complicaciones locales relacionadas con la progresión del tumor primario, lo que apoya la realización de esta intervención en pacientes con enfermedad metastásica. La ausencia de recomendaciones formales subraya la necesidad de evaluar los beneficios de la cirugía caso por caso, presentando la evidencia disponibles a los pacientes para un proceso de toma de decisiones compartido, teniendo en cuenta las futuras complicaciones locales que podrían ser difíciles de manejar.

Introduction Prostate cancer is one of the most frequent cancers in Chile, with 8157 new cases in 2020. Worldwide, 5 to 10% of men have metastatic disease at diagnosis, and androgen deprivation therapy with or without chemotherapy is the standard of care for these patients. The use of local treatment in this setting has no formal recommendation due to the lack of high- quality evidence. Some retrospective studies have sought to elucidate the benefit of surgery on the primary tumor in the setting of metastatic disease since it has been proven to be an effective local treatment for other metastatic malignant diseases. Despite these efforts, the benefit of cytoreductive radical prostatectomy as local treatment in these patients remains unclear. Methods We searched Epistemonikos, the largest database of systematic reviews in health, which is main-tained by screening multiple information sources, including MEDLINE, EMBASE, and Cochrane, among others. We extracted data from systematic reviews, reanalyzed data from primary studies, conducted a meta- analysis, and generated a summary results table using the GRADE approach. Results and conclusions We identified 12 systematic reviews, including seven studies in total, none of which was a trial. Only six of those seven primary studies were used in the results summary. Despite the lack of high- quality evidence, the results summary shows the benefits of performing surgery on the primary tumor in terms of all- cause mortality, cancer- specific mortality, and disease progression. There was also a potential benefit in local complications related to the progression of the prima-ry tumor, supporting the implementation of this intervention in patients with metastatic disease. The absence of formal recommendations highlights the need to evaluate the benefits of surgery on a case- by- case basis, presenting the available evidence to patients for a shared decision- making process and considering future local complications that could be difficult to manage.

Transmesocolic pyeloplasty: experience of a single center.

PURPOSE: We present our experience with dismembered left-sided pyeloplasty using a transmesocolic technique as a way to reduce operative time and facilitate repair by avoiding colon displacement. PATIENTS AND METHODS: Between January 2004 and January 2006, a total of 11 transmesocolic laparoscopic pyeloplasties were performed by the same surgeon at our institution. The mean patient age was 41.6 years (range 14-65 years). Operative records and follow-up were reviewed. RESULTS: A dismembered Anderson-Hynes pyeloplasty was carried out in nine patients (82%), while a Y-V plasty (9%) and a Fengerplasty (9%) were done in one patient each. Crossing vessels were observed in 8 patients (73%). A ureteral stent was left in all patients. The mean operative time was 88.6 minutes (range 60-125 minutes), and blood loss was minimal. Compared with classic transperitoneal laparoscopic left pyeloplasties, transmesocolic cases showed a significant reduction in operative time (88.6 minutes v 117 minutes; P < 0.05). There were no intraoperative complications or open conversions. The mean hospital stay was 2.1 days (range 2-3 days). Only 1 patient (9%) demonstrated narrowing of the anastomosis, which occurred 12 months after a Fengerplasty. CONCLUSIONS: The transmesocolic approach to a dilated left pelvis enables a shorter operative time without increasing morbidity. More patients and longer follow-up are necessary to determine its effect on convalescence.

Bilateral laparoscopic adrenalectomy.

BACKGROUND AND PURPOSE: Laparoscopic adrenalectomy has become the gold standard in the surgical management of adrenal pathology. Bilateral adrenalectomy is indicated in patients with Cushing's disease secondary to macroadenoma or hypophysial hyperplasia in whom medical treatment and transsphenoid surgery have failed. Also, it is the first choice for bilateral benign tumors and metastatic neoplasia. We present our experience with bilateral laparoscopic adrenalectomy, analyzing its indications, feasibility, results, and complications. PATIENTS AND METHODS: Between November 1999 and December 2005, 221 laparoscopic adrenalectomies were performed by the same surgeon (OAC) at our institution. Of the 221 adrenalectomies, 44 were bilateral. A total of 20 patients underwent bilateral synchronic laparoscopic adrenalectomy (91%); the remaining 2 had two-stage procedures. There were 6 cases of bilateral pheochromocytoma, 6 patients with Cushing's disease, 3 cases of metastasis, 3 congenital adrenal hyperplasias, 2 hyperaldosteronisms, and a single case each of adrenal adenoma and myelolipoma. The average patient age was 41.6 years (range 17-72 years), and the male-to-female ratio was 1:2.6. RESULTS: Total laparoscopic adrenalectomy and partial adrenalectomy were performed on 37 and 7 occasions (84% and 16%), respectively. The mean tumor size was 4.15 cm (range 1-11 cm). The mean operative time for each adrenalectomy was 79.2 minutes (range 25-210 minutes). The estimated intraoperative blood loss was on average 65.4 mL (range 0-500 mL). Only one patient required a blood transfusion. There was only one intraoperative complication (2.2%), a renal-vein injury that was controlled with intracorporeal suturing. There were no open conversions. The mean hospital stay was 3.19 days (range 2-5 days). CONCLUSIONS: Bilateral laparoscopic adrenalectomy is technically feasible and can be performed with minimal bleeding in a reasonable surgical time.

STING Report: convenient web-based application for graphic and tabular presentations of protein sequence, structure and function descriptors from the STING database.

The Sting Report is a versatile web-based application for extraction and presentation of detailed information about any individual amino acid of a protein structure stored in the STING Database. The extracted information is presented as a series of GIF images and tables, containing the values of up to 125 sequence/structure/function descriptors/parameters. The GIF images are generated by the Gold STING modules. The HTML page resulting from the STING Report query can be printed and, most importantly, it can be composed and visualized on a computer platform with an elementary configuration. Using the STING Report, a user can generate a collection of customized reports for amino acids of specific interest. Such a collection comes as an ideal match for a demand for the rapid and detailed consultation and documentation of data about structure/function. The inclusion of information generated with STING Report in a research report or even a textbook, allows for the increased density of its contents. STING Report is freely accessible within the Gold STING Suite at http://www.cbi.cnptia.embrapa.br, http://www.es.embnet.org/SMS/, http://gibk26.bse.kyutech.ac.jp/SMS/ and http://trantor.bioc.columbia.edu/SMS (option: STING Report).

Laparoscopic radical cystoprostatectomy and in block urethrectomy in urethral cancer: initial experience in 2 cases.

We introduce laparoscopic radical cystoprostatectomy and in block urethrectomy as an option for the treatment of urethral cancer in men. Using a 5-port transperitoneal approach, a radical cystoprostatectomy is completed laparoscopically with bilateral iliac and pelvic lymphadenectomy. Urethrectomy and extraction of bladder and prostate is performed through a perineal incision. A segment of ileum is isolated and exteriorized to create an extracorporeal ileal conduit and restore ileo-ileal continuity by open standard technique. Bilateral stented uretero-ileal anastomosis is extracorporeally performed. Total operative time ranges from 4.5 to 4.8 hours. Laparoscopic radical cystoprostatectomy with perineal urethrectomy and an extracorporeally made ileal conduit is a feasible technique that can be reproduced. To our knowledge, this is the first report of laparoscopic radical surgery in the treatment of urethral cancer in men.

Presentación inusual del síndrome de Lutembacher / Unusual presentation of Lutembacher’s syndrome

Resumen Introducción: El síndrome de Lutembacher corresponde a la asociación de un defecto interauricular (congénito o iatrogénico) e insuficiencia o estenosis mitral (congénita o adquirida). La etiología reumática es la causa más frecuente del compromiso mitral. Tiene una prevalencia reportada de 0.001 por cada 1.000.000 habitantes. Caso clínico: Paciente femenina de 6 años con cuadro de 10 meses de palpitaciones asociadas a dolor torácico. Se realizó un electrogardiograma en el que se evidenció bloqueo incompleto de la rama derecha del haz de His y prolongación del intervalo PR, además de un ecocardiograma en el que se visualizó una comunicación interauricular tipo ostium secundum no restrictiva de 28 mm, con cortocircuito de izquierda a derecha, dilatación del ventrículo derecho, prolapso de válvula mitral, valvas engrosadas e insuficiencia mitral moderada a grave. Se realizó plastia de válvula mitral y cierre quirúrgico de la comunicación interauricular, sin complicaciones. Durante el seguimiento se encuentra asintomática desde el punto de vista cardiovascular, en manejo farmacológico. Conclusiones: La asociación Lutembacher tiene una prevalencia de 0.001/1.000.000 habitantes; la mayoría tiene etiología reumática. La paciente no tiene historia de fiebre reumática y sería la paciente más joven reportada en la literatura con síndrome de Lutembacher.

Abstract Introduction: Lutembacher’s syndrome corresponds to the association of an atrial septal defect (congenital or iatrogenic) and mitral regurgitation or stenosis (congenital or acquired), with rheumatic etiology being the most-frequent cause of mitral regurgitation. It has a reported prevalence of 0.001 for every 1,000,000 inhabitants. Clinical case: Female patient six years of age with a 10-month condition of palpitations associated with chest pain. An electrocardiogram was performed with evidence of incomplete right His bundle branch block and PR interval prolongation; additionally, an echocardiogram showed 28-mm non-restrictive ostium secundum atrial septal defect, with left-to-right shunt, right ventricular dilation, mitral valve prolapse, thickened valves, and moderate-to-severe mitral regurgitation. Mitral valve plasty and surgical closure of the atrial septal defect were performed, without complications. During follow-up, she was asymptomatic from the cardiovascular point of view, under pharmacological management. Conclusions: Lutembacher’s association has a prevalence of 0.001/1´000.000 inhabitants; the majority with rheumatic etiology. Our patient has no history of rheumatic fever and would be the youngest patient reported in the literature with Lutembacher’s syndrome.

Case report: Laparoscopy-assisted urinary undiversion: transforming an ileal conduit into an orthotopic continent neobladder.

PURPOSE: To describe the technique of laparoscopy-assisted undiversion of an ileal conduit into a continent orthotopic ileal neobladder performed on a patient with a previous radical cystoprostatectomy and ileal conduit. CASE REPORT: A 57-year-old man presented with a prolapsed stoma and a history of a right radical nephroureterectomy for grade 3 ureteral transitional-cell carcinoma and a radical cystoprostatectomy and ileal conduit urinary diversion for in-situ bladder carcinoma, performed 12 and 8 years ago, respectively. After the ileal stoma was resected, five trocars were placed transperitoneally. Partial resection of the distal ileal conduit was performed, leaving in place the proximal segment with its left ureteroileal anastomosis. Flexible urethroscopy revealed a contracting external sphincter, and random urethral frozen-section biopsies ruled out tumor. A 45-cm segment of ileum was isolated and exteriorized through the stoma site, and an ileal neobladder was created extracorporeally, suturing the proximal ileal-conduit segment, with its ureteroileal anastomosis, to it. The ileal neobladder was reintroduced into the abdomen and anastomosed laparoscopically to the urethral stump with six 2-0 polyglactin sutures. The total operative time was 7 hours with a blood loss of 100 mL. There were no intraoperative complications. The hospital stay was 7 days. At a follow-up of 24 months, the patient had total daytime continence and normal renal function, and intravenous urography revealed an unobstructed urinary tract. CONCLUSION: Laparoscopy-assisted ileal-conduit undiversion into an orthotopic ileal neobladder is technically feasible. It can be considered an alternative to open surgery for patients who have undergone urinary diversion.

JavaProtein Dossier: a novel web-based data visualization tool for comprehensive analysis of protein structure.

JavaProtein Dossier ((J)PD) is a new concept, database and visualization tool providing one of the largest collections of the physicochemical parameters describing proteins' structure, stability, function and interaction with other macromolecules. By collecting as many descriptors/parameters as possible within a single database, we can achieve a better use of the available data and information. Furthermore, data grouping allows us to generate different parameters with the potential to provide new insights into the sequence-structure-function relationship. In (J)PD, residue selection can be performed according to multiple criteria. (J)PD can simultaneously display and analyze all the physicochemical parameters of any pair of structures, using precalculated structural alignments, allowing direct parameter comparison at corresponding amino acid positions among homologous structures. In order to focus on the physicochemical (and consequently pharmacological) profile of proteins, visualization tools (showing the structure and structural parameters) also had to be optimized. Our response to this challenge was the use of Java technology with its exceptional level of interactivity. (J)PD is freely accessible (within the Gold Sting Suite) at http://sms.cbi.cnptia.embrapa.br, http://mirrors.rcsb.org/SMS, http://trantor.bioc.columbia.edu/SMS and http://www.es.embnet.org/SMS/ (Option: (Java)Protein Dossier).

Maximum swimming speeds of sailfish and three other large marine predatory fish species based on muscle contraction time and stride length: a myth revisited.

Billfishes are considered to be among the fastest swimmers in the oceans. Previous studies have estimated maximum speed of sailfish and black marlin at around 35 m s-1 but theoretical work on cavitation predicts that such extreme speed is unlikely. Here we investigated maximum speed of sailfish, and three other large marine pelagic predatory fish species, by measuring the twitch contraction time of anaerobic swimming muscle. The highest estimated maximum swimming speeds were found in sailfish (8.3±1.4 m s-1), followed by barracuda (6.2±1.0 m s-1), little tunny (5.6±0.2 m s-1) and dorado (4.0±0.9 m s-1); although size-corrected performance was highest in little tunny and lowest in sailfish. Contrary to previously reported estimates, our results suggest that sailfish are incapable of exceeding swimming speeds of 10-15 m s-1, which corresponds to the speed at which cavitation is predicted to occur, with destructive consequences for fin tissues.

Nucleophilic addition to electron-rich heteroaromatics: dearomatizing anionic cyclizations of pyrrolecarboxamides.

[reaction: see text] Despite its electron-rich nature, a pyrrole ring is susceptible to intramolecular nucleophilic attack by organolithiums. The resulting dearomatizing anionic cyclization yields new 5- or 7-membered heterocyclic rings. Formation of a new 5-membered ring, by cyclization of an N-benzylpyrrolecarboxamide, is accompanied by ring opening of the original pyrrole to yield 3-aminovinylpyrrolinones. Formation of a new 7-membered ring, by cyclization of an N-allyl pyrrolecarboxamide, yields bicyclic pyrroloazepinones.