The Evolutionary History of Siphonophore Tentilla: Novelties, Convergence, and Integration.

Synopsis Siphonophores are free-living predatory colonial hydrozoan cnidarians found in every region of the ocean. Siphonophore tentilla (tentacle side branches) are unique biological structures for prey capture, composed of a complex arrangement of cnidocytes (stinging cells) bearing different types of nematocysts (stinging capsules) and auxiliary structures. Tentilla present an extensive morphological and functional diversity across species. While associations between tentillum form and diet have been reported, the evolutionary history giving rise to this morphological diversity is largely unexplored. Here we examine the evolutionary gains and losses of novel tentillum substructures and nematocyst types on the most recent siphonophore phylogeny. Tentilla have a precisely coordinated high-speed strike mechanism of synchronous unwinding and nematocyst discharge. Here we characterize the kinematic diversity of this prey capture reaction using high-speed video and find relationships with morphological characters. Since tentillum discharge occurs in synchrony across a broad morphological diversity, we evaluate how phenotypic integration is maintaining character correlations across evolutionary time. We found that the tentillum morphospace has low dimensionality, identified instances of heterochrony and morphological convergence, and generated hypotheses on the diets of understudied siphonophore species. Our findings indicate that siphonophore tentilla are phenotypically integrated structures with a complex evolutionary history leading to a phylogenetically-structured diversity of forms that are predictive of kinematic performance and feeding habits.

Los sifonóforos son cnidarios hidrozoos coloniales depredadores que habitan todas las regiones pelágicas del océano. Las téntilas (ramificaciones laterales de los tentáculos) de los sifonóforos son estructuras biológicas dedicadas a la captura de presas. Las téntilas se componen de una matriz compleja de cnidocitos (células urticantes) portadores de diferentes tipos de nematocistes (cápsulas urticantes) y estructuras auxiliares. Las téntilas presenta una extensa diversidad morfológica y funcional en las diferentes especies de sifonóforo. Las relaciones entre la forma de las téntilas y las dietas de los sifonóforos has sido estudiadas previamente, sin embargo, la historia evolutiva que dio lugar a esta diversidad morfológica no ha sido explorada apenas. En este estudio examinamos las adquisiciones y pérdidas evolutivas de las subestructuras de la téntila y los tipos de nematocisto utilizando la filogenia molecular más reciente de los sifonóforos. Las téntilas presentan un mecanismo de disparo a alta velocidad, sincronizando las diferentes subestructuras con gran precisión, durante el cual se la téntila de desenrolla mientras los nematocistes se disparan sobre la presa. En este estudio caracterizamos la diversidad cinemática de estas reacciones para la captura de presas utilizando video de alta velocidad, y describimos su relación con los caracteres morfológicos. Dado que la descarga de las téntilas ocurre en sincronía en toda su diversidad morfológica, hemos evaluado cómo la evolución con integración fenotípica mantiene las correlaciones entre los caracteres morfológicos a través del tiempo. Hallamos que el morfo-espacio de las téntilas tiene baja dimensionalidad, encontramos casos de heterocronía y convergencia morfológica, y generamos hipótesis sobre las dietas de especies de sifonóforo poco estudiadas. Nuestros hallazgos indican que las téntilas de los sifonóforos son estructuras con fenotipos integrados y con una historia evolutiva compleja que ha dado lugar a una diversidad filogenéticamente estructurada de formas asociadas a diferentes rendimientos cinemáticos y hábitos alimenticios.

Description of Tottonophyes enigmatica gen. nov., sp. nov. (Hydrozoa, Siphonophora, Calycophorae), with a reappraisal of the function and homology of nectophoral canals.

A new species of calycophoran siphonophore, Tottonophyes enigmatica gen. nov, sp. nov., is described. It has a unique combination of traits, some shared with prayomorphs (including two rounded nectophores) and some with clausophyid diphyomorphs (the nectophores are dissimilar, with one slightly larger and slightly to the anterior of the other, and both possess a somatocyst). Molecular phylogenetic analyses indicate that the new species is the sister group to all other diphyomorphs. A new family, Tottonophyidae, is established for it. Its phylogenetic position and distinct morphology help clarify diphyomorph evolution. The function and homology of the nectophoral canals and somatocyst is also re-examined and further clarification is given to their nomenclature.

Alcohol problems in women admitted to a level I trauma center: a gender-based comparison.

BACKGROUND: Male patients constitute such a large proportion of trauma patients that most studies of alcohol problems in trauma patients have been carried out with clinical data largely or totally contributed by male patients. It may be incorrect to assume that the nature of alcoholism in women and men is identical, or that the size of the problem among women is small, eliminating the need to specifically study female patients. The purpose of this study was to perform a gender-based comparison of alcohol problems in trauma patients. METHODS: Admitted injured patients underwent routine screening, including a blood alcohol concentration, serum gamma-glutamyl transpeptidase, and the Short Michigan Alcohol Screening Test. A random sample of screen positive women and men underwent a comprehensive alcohol use and psychosocial assessment, and the results were compared by gender. RESULTS: The screen-positive rate was higher for men, 51% versus 34% (p < 0.01). However, screen-positive women and men had similar problem severity as reflected by mean blood alcohol concentration (162 mg/dL vs. 142 mg/dL, p = 0.16) and Short Michigan Alcohol Screening Test scores (4.6 vs. 5.0, p = 0.32). The Alcohol Use Disorders Identification Test, NIMH-DIS, and Severity of Alcohol Dependence Data form showed that female trauma patients with alcohol problems have the same severity of dependence symptoms as men. However, women were significantly more likely to have liver dysfunction, depression, psychological distress, and recent physical, emotional, or sexual abuse. CONCLUSION: Alcohol problems are more common in male trauma patients, but women with alcohol problems are just as severely impaired, have at least as many adverse consequences of alcohol use as their male counterparts, and have more evidence of alcohol-related physical and psychological harm.

Alcohol interventions in a trauma center as a means of reducing the risk of injury recurrence.

OBJECTIVE: Alcoholism is the leading risk factor for injury. The authors hypothesized that providing brief alcohol interventions as a routine component of trauma care would significantly reduce alcohol consumption and would decrease the rate of trauma recidivism. METHODS: This study was a randomized, prospective controlled trial in a level 1 trauma center. Patients were screened using a blood alcohol concentration, gamma glutamyl transpeptidase level, and short Michigan Alcoholism Screening Test (SMAST). Those with positive results were randomized to a brief intervention or control group. Reinjury was detected by a computerized search of emergency department and statewide hospital discharge records, and 6- and 12-month interviews were conducted to assess alcohol use. RESULTS: A total of 2524 patients were screened; 1153 screened positive (46%). Three hundred sixty-six were randomized to the intervention group, and 396 to controls. At 12 months, the intervention group decreased alcohol consumption by 21.8+/-3.7 drinks per week; in the control group, the decrease was 6.7+/-5.8 (p = 0.03). The reduction was most apparent in patients with mild to moderate alcohol problems (SMAST score 3 to 8); they had 21.6+/-4.2 fewer drinks per week, compared to an increase of 2.3+/-8.3 drinks per week in controls (p < 0.01). There was a 47% reduction in injuries requiring either emergency department or trauma center admission (hazard ratio 0.53, 95% confidence interval 0.26 to 1.07, p = 0.07) and a 48% reduction in injuries requiring hospital admission (3 years follow-up). CONCLUSION: Alcohol interventions are associated with a reduction in alcohol intake and a reduced risk of trauma recidivism. Given the prevalence of alcohol problems in trauma centers, screening, intervention, and counseling for alcohol problems should be routine.

Practical guidelines for performing alcohol interventions in trauma centers.

Nearly 50% of trauma patients are injured while under the influence of alcohol; however, addressing alcohol problems is not considered a routine component of trauma care. A public health approach to trauma prevention should include attention to underlying risk factors in the same way that advice regarding smoking cessation is offered in adult respiratory medicine clinics, and blood pressure, cholesterol, dietary, and exercise advice is provided in coronary care units. The Department of Health and Human Services, in its recent report to Congress, stated that efforts to reduce death and disability from injuries must be combined with efforts to reduce alcohol abuse, and called for an increase in the use of alcohol interventions in trauma patients. According to the National Academy of Sciences, the responsibility to provide counseling for patients with uncomplicated cases of mild to moderate alcohol abuse lies not with specialized alcohol treatment centers, but with physicians and other health care staff in general hospital settings trained to provide brief interventions. This paper provides practical guidelines for the administration of alcohol interventions that are suitable for trauma center use, and that have documented efficacy in reducing alcohol consumption.

Linking substance abuse services with general medical care: integrated, brief interventions with hospitalized patients.

This paper presents the results of implementing on-site alcohol or drug (AOD) brief intervention services across several medical, surgical, and psychiatric services in a county hospital. These integrated brief interventions (IBI) included patient substance abuse assessment, feedback to patient, and referral/recommendations. Three hundred sixty-three patients were referred by hospital staff to these services and 95% of these patients were subsequently confirmed by chemical dependency specialists as having diagnoses of psychoactive substance abuse or dependence. Seventy-nine percent of chemically dependent patients were without current substance abuse treatment, even though 54% were partially motivated and 20% were fully motivated for getting treatment. Of patients contacted at follow-up, 35% reported involvement in some kind of substance abuse treatment or 12-step meetings. Implications for implementing integrated brief intervention services are discussed in light of recent trends in publicly funded treatment availability and brief intervention outcome studies.

Alcohol interventions in trauma centers. Current practice and future directions.

Nearly half of all trauma beds are occupied by patients who were injured while under the influence of alcohol. Alcoholism plays such a significant role in trauma that efforts to reduce injury recurrence are unlikely to be successful if it remains untreated. An injury requiring hospitalization creates a unique opportunity to intervene and to motivate patients to alter their drinking behavior, thereby making trauma centers ideal sites to implement an alcohol screening, intervention, and referral program. However, despite emphasis on injury control and prevention, little has been done to incorporate alcohol intervention programs into care of the injured patient. Effective means of intervention exist that are consistent with the time, financial, and staffing constraints of trauma centers, and they should be implemented.

Role of angiotensin II in neonatal sepsis.

Previous studies in adult animals have indicated that plasma angiotensin converting enzyme (ACE) activity is inhibited by endotoxin. Reduced ACE activity may decrease plasma angiotensin II (AII) levels, contributing to the refractory hypotension we have previously reported in neonatal septic shock. In this study, hemodynamic function, plasma renin activity (PRA), AII, prostacyclin (PGI2), and thromboxane B2 (TxB2) levels were measured in 17-20-day-old dogs before and 1, 2, and 3 hr after endotoxin administration (1 mg/kg, Escherichia coli lipopolysaccharide-B). PRA and AII levels rose significantly 60 min post-endotoxin, returning to baseline values by 180 min; PGI2 and thromboxane B2 levels rose post-endotoxin and remained elevated. Indomethacin or captopril was given by oral gavage 30-35 min before endotoxin. Captopril significantly blunted the rise in PRA and AII, while indomethacin blocked the rise in PGI2 and TxB2. Mean arterial blood pressure and cardiac output fell 60 min after endotoxin challenge without pharmacologic intervention and remained depressed. Our data suggest that renin and AII responses to endotoxin challenge remain intact in the neonatal subject. Maintenance of hemodynamics in indomethacin-pretreated dogs may be due to unopposed stimulation of the peripheral vasculature by AII. Thromboxane B2 in maintenance of vasomotor tone may be minimal in the young.

Pheochromocytoma with extension into the inferior vena cava: a case report.

Eleven cases of pheochromocytoma with extension into the inferior vena cava have been reported previously. This report describes a case of a right adrenal pheochromocytoma with extension into the inferior vena cava that was removed with the aid of cardiopulmonary bypass and circulatory arrest.

Effects of relief of biliary obstruction on mononuclear phagocyte system function and cell mediated immunity.

Obstructive jaundice causes depression of immune system function but it is unclear at present how rapidly immune function recovers after relief of biliary obstruction. To address this issue, we studied 218 Sprague-Dawley rats with common bile duct obstruction. Mononuclear phagocyte function, cell mediated immune function, portal-systemic shunt fraction, liver function tests, and liver histology were evaluated in normal (sham) rats, obstructed rats, and at weekly intervals after relief of biliary obstruction. Hepatic uptake of radiolabelled bacteria was 82 per cent in sham rats and 66 per cent in rats 21 days after CBD obstruction (P less than 0.05). Phagocytic activity returned to normal within 7 days after choledochoduodenostomy. Cell mediated immunity, measured by skin graft rejection, was significantly prolonged in the obstructed group (P less than 0.05) but had returned to normal 7 days after biliary diversion. Return of hepatocellular function, as measured by liver function tests, paralleled recovery of immune function. This study demonstrates prompt recovery of the immune system after internal biliary drainage for obstructive jaundice. This finding is in contrast to previous studies that demonstrated persistent immune suppression months after biliary diversion. These data may have implications concerning the usefulness of internal biliary drainage before surgery in patients with obstructive jaundice.

Contribution of portal systemic shunt to Kupffer cell dysfunction in obstructive jaundice.

Previous animal models of biliary tract obstruction have shown that hepatic phagocytic activity is impaired secondary to Kupffer cell dysfunction. Biliary tract obstruction leads to portal hypertension and an associated portal systemic shunt. Forty-eight Sprague-Dawley rats were studied to determine the contribution of portal systemic shunt to Kupffer cell dysfunction after 21 days of obstructive jaundice or sham operation. Liver uptake of radiolabeled Escherichia coli decreased from 76.1 +/- 1.4% (sham) to 63.1 +/- 6.1% in the common duct ligation (CDL) rats (P less than 0.05); lung uptake increased from 4.0 +/- 0.6% (sham) to 20.2 +/- 4.5 (CDL) (P less than 0.05). Portal systemic shunt, determined using radioactive microspheres, increased from 2.0 +/- 1.0% (sham) to 46.6 +/- 13.1% (CDL), P less than 0.05. Although a significant portal systemic shunt does exist in this 21-day model of obstructive jaundice, it does not appear to be the only mechanism underlying Kupffer cell dysfunction.

Muramyl dipeptide improves mononuclear phagocyte system function in obstructive jaundice.

Previous studies have demonstrated depression of the mononuclear phagocyte system (MPS) of which the liver comprises 80-85% in animals subjected to 21 days of obstructive jaundice. This study examined the ability of a macrophage stimulant, muramyl dipeptide (MDP), to reverse MPS dysfunction in an obstructive jaundice rat model. Sixty-two male Sprague-Dawley rats underwent sham (n = 29) laparotomy or common duct ligation (CDL) (n = 33) and were studied after 21 days. Animals were injected with 1-3.5 X 10(6) Escherichia coli via a lateral tail vein, and colony-forming units (CFU) of the liver, lung, and spleen were determined at two time intervals: 30 min postinjection to determine the phagocytic activity of MPS (sham, n = 16; CDL, n = 20) and 24 hr postinjection to determine cytotoxic activity of MPS (sham, n = 13; CDL, n = 13). MDP (3 micrograms/g) was administered subcutaneously 24 hr prior to E. coli injection in 6 sham and 10 CDL rats studied at the 30-min time interval and 7 sham and 7 CDL rats studied at the 24-hr time interval. Pretreatment with MDP appeared to reverse the impairment of phagocytic activity in the liver of CDL rats returning it to the level of sham animals (P less than 0.05). However, pretreatment with MDP did not enhance the cytotoxic activity of the MPS as evidenced by higher CFU of E. coli in the liver, lung, and spleen of CDL animals pretreated with MDP as compared to CDL animals that did not receive MDP pretreatment. This increase was only significant in the spleen.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypertonic saline-dextran resuscitation of acute canine bile-induced pancreatitis.

In this study, we examined the effects of hypertonic saline-dextran resuscitation (2,400 mOsm of sodium chloride, 6 percent dextran 70) on cardiopulmonary function and extravascular lung water in acute canine pancreatitis. Acute pancreatitis was induced in 21 dogs by injecting 0.5 ml/kg of autologous bile into the pancreatic duct. In 10 dogs, resuscitation was begun with a 4 ml/kg bolus of hypertonic saline-dextran solution; 11 dogs received no bolus. Lactated Ringer's solution was infused in all dogs to maintain mean arterial pressure and cardiac output at baseline values. Pulmonary hypertension accompanied by a significant increase in pulmonary vascular resistance and a decrease in lung blood flow occurred in those dogs resuscitated with lactated Ringer's solution alone. By contrast, dogs in the hypertonic saline-dextran group maintained pulmonary artery pressure and pulmonary vascular resistance at baseline values while nutritive blood flow to the lung decreased progressively. Our data suggest that hypertonic saline-dextran resuscitation effectively restores cardiac function while it significantly reduces fluid requirements, as well as the pulmonary hypertension and pulmonary edema that frequently accompany lactated Ringer's resuscitation of acute pancreatitis.

Additive effect of an immunomodulator and broad-spectrum antibiotic in fecal peritonitis.

We examined the effect of muramyl dipeptide (3 micrograms/g body weight) and a broad-spectrum antibiotic cefoxitin (15 mg/kg) on survival and systemic bacteremia in rats with peritonitis. When muramyl dipeptide given 24 hours prior to placement of the bacterial inoculum was combined with a single prophylactic dose of cefoxitin, survival was 100 percent (p less than 0.001) and systemic bacteremia at 4 hours postinoculation was significantly decreased. Twenty-four hour pretreatment with either muramyl dipeptide alone or cefoxitin alone was associated with survival rates of 43 percent and 56 percent, respectively. When muramyl dipeptide was given with cefoxitin at the time of administration of the bacterial inoculum, no survival advantage was seen over the use of cefoxitin alone. There were no significant differences among groups in quantitative bacteremia at 24 hours postinoculation or in the number of intraabdominal abscesses. This study clearly demonstrates an additive effect of muramyl dipeptide pretreatment given with a prophylactic dose of cefoxitin in a human fecal peritonitis rat model.