An Update of the Cenchrinae (Poaceae, Panicoideae, Paniceae) and a New Genus for the Subtribe to Clarify the Dubious Position of a Species of Panicum L.

Subtribe Cenchrinae, so-called as the "bristle clade", is a monophyletic group of panicoid grasses characterized by having sterile branches or bristles on the inflorescences in most of its species. Within this subtribe is also placed Panicum antidotale Retz., an "incertae sedis" species of Panicum L. which lacks bristles along the inflorescence. In this study, we present an update of the subtribe Cenchrinae based on molecular, morphological, and anatomical evidence to clarify the systematic position of P. antidotale in the Cenchrinae, excluding it from Panicum and establishing it in a new genus (i.e., Janochloa Zuloaga & Delfini); the morphological features distinguishing the new genus from other closely related taxa are properly discussed and an identification key to the 24 genera recognized within Cenchrinae is presented. We also add American Setaria species, not tested before, of subgenera Paurochaetium and Reverchoniae, discussing the position of these taxa in actual phylogeny of the genus as well as defining placements in the tree of Setaria species that were imprecisely located in previous analyses. A comparison with the results from other studies, comments on Stenotaphrum Trin. and a brief discussion on conflicting placements in Cenchrus and related taxa, and of Acritochaete Pilg. are also included.

Role of Oxidative Stress in Lithium-Induced Nephropathy.

Long-term lithium treatment was associated with chronic kidney disease and renal failure although the underlying pathogenic mechanisms are not certainty known. The aim of this study was to evaluate changes in oxidative stress measures as well as renal functional and structural alterations associated with chronic use of lithium in rats. Forty Wistar male rats were randomized into four groups: control groups fed ad libitum powered standard diet for 1 and 3 months and experimental groups fed ad libitum the same diet supplemented with 60 mmol/kg diet for 1 and 3 months. Histopathological changes, laboratory parameters, and oxidative stress measurements were assessed at months 1 and 3. The experimental animals showed alteration of the cortical tubules from the first month of lithium-treatment and a decrease in the glomerular filtration rate and in the glomerular area at the third month. There was an increase in thiobarbituric acid reactive substances and carbonyls, as well as an increase in reduced glutathione, in the kidney of rats exposed to lithium. These changes were evident from the first month of treatment and remained throughout the experiment. Our results suggest that, oxidative stress could be one of the pathogenic mechanisms involved in the structural and functional alterations of the kidney associated with prolonged use of lithium. The study of the pathogenic mechanisms involved in lithium-induced nephropathy is a critical issue for the development of new strategies for prevention and/or early detection.

Copper(II) and iron(III) ions inhibit respiration and increase free radical-mediated phospholipid peroxidation in rat liver mitochondria: Effect of antioxidants.

Rat liver mitochondria (1.5-2.1mg protein·mL-1) supplemented with either 25 and 100µM Cu2+ or 100 and 500µM Fe3+ show inhibition of active respiration (O2 consumption in state 3) and increased phospholipid peroxidation . Liver mitochondria were supplemented with the antioxidants reduced glutathione, N-acetylcysteine or butylated hydroxitoluene, to evaluate their effects on the above-mentioned alterations. Although the mitochondrial dysfunction is clearly associated to phospholipid peroxidation, the different responses to antioxidant supplementation indicate that the metal ions have differences in their mechanisms of toxicity. Mitochondrial phospholipid peroxidation through the formation of hydroxyl radical by a Fenton/Haber-Weiss mechanism seems to precede the respiratory inhibition and to be the main fact in Fe-induced mitochondrial dysfunction. In the case of Cu2+, it seems that the ion oxidizes glutathione, and low molecular weight protein thiol groups in a direct reaction, as part of its intracellular redox cycling. The processes involving phospholipid peroxidation, protein oxidation and mitochondrial respiratory inhibition characterize a redox dyshomeostatic situation that ultimately leads to cell death. However, Cu2+ exposure involves an additional, yet unidentified, toxic event as previous reduction of the metal with N-acetylcysteine has only a minor effect in preventing the mitochondrial damage.

Rat liver mitochondrial dysfunction by addition of copper(II) or iron(III) ions.

Increased copper (Cu) and iron (Fe) levels in liver and brain are associated to oxidative stress and damage with increased phospholipid oxidation process. The aim of this work was to assess the toxic effects of Cu2+ and Fe3+ addition to rat liver mitochondria by determining mitochondrial respiration in states 3 (active respiration) and 4 (resting respiration), and phospholipid peroxidation. Both, Cu2+ and Fe3+ produced decreases in O2 consumption in a concentration-dependent manner in active state 3: both ions by 42% with malate-glutamate as complex I substrate (concentration for half maximal response (C50) 60µM Cu2+ and 1.25mM Fe3+), and with succinate as complex II substrate: 64-69% with C50 of 50µM Cu2+ and with C50 of 1.25mM of Fe3+. Respiratory control decreased with Cu2+ (C50 50µM) and Fe3+ (C50 1.25-1-75mM) with both substrates. Cu2+ produced a 2-fold increase and Fe3+ a 5-fold increase of thiobarbituric acid-reactive substances (TBARS) content from 25µM Cu2+ (C50 40µM) and from 100µM Fe3+ (C50 1.75mM). Supplementations with Cu2+ and Fe3+ ions induce mitochondrial dysfunction with phospholipid peroxidation in rat liver mitochondria. Although is proved that a Fenton/Haber Weiss mechanism of oxidative damage occurs in metal-ion induced mitochondrial toxicity, slightly different responses to the metal ions suggest some differences in the mechanism of intracellular toxicity. The decreased rates of mitochondrial respiration and the alteration of mitochondrial function by phospholipid and protein oxidations lead to mitochondrial dysfunction, cellular dyshomeostasis and cell death.

Case report: misdiagnosis of tailgut cyst presenting as recurrent perianal fistula with pelvic abscess.

Tailgut cysts are uncommon lesions that usually occur within the presacral space. The relative rarity and nonspecific complaints associated with these lesions often lead to misdiagnosis or unnecessary procedures before the correct diagnosis is made. We describe a case of a 16-year-old female who presented with pelvic pain. She had previously undergone several procedures at an outside institution for recurrent perianal fistula and perirectal abscess. Subsequent evaluation under anesthesia revealed a presacral cystic mass with a well-developed tract within the anorectal ring in the posterior midline. This mass was surgically removed using a combined transanal and posterior sagittal excision technique and was found to be a tailgut cyst upon pathologic evaluation. Tailgut cysts and other presacral masses should be included in the differential for patients with recurrent abscess in the presacral space or fistula within the anal canal. A variety of surgical approaches are available depending on the anatomy of the lesion.

Glyphosate-induced structural variations in Commelina erecta L. (Commelinaceae).

The purpose of this study was to analyze the structural variations of Commelina erecta, a glyphosate-tolerant weed, produced by this herbicide. Regrowth shoots (vegetative cloning axes) and seedlings and two glyphosate concentrations: 900 and 1800 grams of acid equivalent per hectare (ga.e. ha⁻¹) were used. The following variations were observed: foliar shape and size changes, changes in the length of internodes, variations in the quantity of inflorescences, low seed production, and differences in the number of branches. After treatment, different phenotypic responses were observed as a result of differential sensitivity to glyphosate. Most of the vegetatively-propagated plants treated with 900 g a.e. ha⁻¹ revealed the same morphological structure as that of controls (i.e. three clearly identifiable zones: a basal or branching zone, a middle zone where branch production is inhibited, and an apical zone where only floral branches are produced). By contrast, the 900 ga.e. ha⁻¹ treated seedlings and the 1800 g a.e. ha⁻¹ treated regrowth shoots and seedlings showed two phenotypic responses, exhibiting differences in the quantity and location of branches and in the survival time of axes. The main variation is seen in branch production in the region that is usually inhibited. The different phenotypic responses and morphological changes suggest that C. erecta shows a very high intraspecific variability, which allows it to survive and thrive even in environments with intensive glyphosate application. These results underscore the need to solve the problem of tolerant weeds by means of an integrated approach including alternative management practices grounded on knowledge of the species and their behavior.

Salinity induced anatomical and morphological changes in Chloris gayana Kunth roots.

Chloris gayana Kunth is a grass species valuable as forage which was introduced into Argentina to be used as pasture in saline soils of subtropical and warm-temperate zones, given its good adaptability to drought, salinity and mild freezing. However, its tolerance varies according to the cultivar. In tetraploid cultivars, important reductions in yield have been observed. Here, a study of the variations produced on the root and stem system by salinity at different NaCl concentrations (0, 150 and 250 mM) was performed in the Boma cultivar, with the aim of determining the anatomical and morphological alterations produced by the salt excess. Plants cultivated with the highest level of salinity showed, in the whole, significant differences in the measured variables. A diminution in absolute values of the variables and a major reduction in vascular tissue dimensions were observed, which suggests that the lack of tolerance to salt stress could be related to a deficient adaptation to absorb and transport water and nutrients from the roots.

Salinity induced anatomical and morphological changes in Chloris gayana Kunth roots

Chloris gayana Kunth is a grass species valuable as forage which was introduced into Argentina to be used as pasture in saline soils of subtropical and warm-temperate zones, given its good adaptability to drought, salinity and mild freezing. However, its tolerance varies according to the cultivar. In tetraploid cultivars, important reductions in yield have been observed. Here, a study of the variations produced on the root and stem system by salinity at different NaCl concentrations (0, 150 and 250 mM) was performed in the Boma cultivar, with the aim of determining the anatomical and morphological alterations produced by the salt excess. Plants cultivated with the highest level of salinity showed, in the whole, significant differences in the measured variables. A diminution in absolute values of the variables and a major reduction in vascular tissue dimensions were observed, which suggests that the lack of tolerance to salt stress could be related to a deficient adaptation to absorb and transport water and nutrients from the roots.

Early ductal decompression versus conservative management for gallstone pancreatitis with ampullary obstruction: a prospective randomized clinical trial.

OBJECTIVE: To compare the efficacy of endoscopic retrograde cholangiopancreatography +/- endoscopic sphincterotomy (ERCP +/- ES) versus traditional conservative management in early gallstone pancreatitis with persistent ampullary obstruction (GSP + AO). SUMMARY BACKGROUND DATA: The effectiveness of early ERCP +/- ES in this setting is controversial. METHODS: Sixty-one consecutive patients with GSP + AO within 48 hours from the onset of symptoms were randomized to receive either conservative treatment and selective ERCP +/- ES after 48 hours (control group, 31 patients) or initial conservative treatment and systematic ERCP +/- ES within 48 hours if obstruction persisted 24 hours or longer (study group, 30 patients). Patient outcome was compared in relation to treatment groups and to duration of obstruction. RESULTS: In the control group, 22 patients disobstructed spontaneously within 48 hours; 3 of the remaining 9 patients underwent ERCP +/- ES and none had impacted stones. In the study group, 16 patients disobstructed spontaneously and 14 underwent ERCP within 48 hours from the onset of symptoms; impacted stones were found and extracted by ES in 79% (11 of 14) of these. PATIENTS: There were no deaths in either group. Patients in the study group showed a shorter period of obstruction (P = 0.016) and a lower rate of immediate complications (P = 0.026) than controls. Patients with obstruction lasting < or =48 hours regardless of the treatment group had fewer immediate complications than those whose obstruction persisted longer (P < 0.001). CONCLUSIONS: This study shows that in patients with GSP + AO limiting the duration of obstruction to not longer than 48 hours by ERCP + ES decreased morbidity.

Thoracoscopic anterior spinal release and fusion: evolution of a faster, improved approach.

PURPOSE: The aim of this study was to compare the perioperative parameters and outcomes of video-assisted thoracoscopic surgery (VATS) with open thoracotomy for anterior release and fusion in the treatment of pediatric spinal deformities. METHODS: Twenty-six patients treated with VATS anterior spinal release and posterior spinal fusion by the authors were reviewed retrospectively. Fourteen age- and disease-matched patients who underwent open thoracotomy for anterior spinal release and posterior spinal fusion by the same group of surgeons during the same time period were evaluated for comparison. Patients whose anterior level of exposure extended below the diaphragm were excluded. RESULTS: Blood loss, operative transfusion, and length of postoperative chest tube use all were decreased in the VATS patients compared with thoracotomy patients (P < or =.05). The average operating time for VATS was less than that for thoracotomy but did not reach statistical significance. However, operating time was significantly shorter in the second 13 VATS patients compared with the first 13 patients. No complications specifically related to the VATS approach were identified. CONCLUSIONS: The VATS technique is a safe and comparable alternative to open thoracotomy. Although there is a learning curve for VATS, greater experience could show an advantage in this approach to the anterior spine for the treatment of pediatric spinal deformity.

Temporary relocation of testes to the anterior abdominal wall before radiation therapy of the pelvis or perineum.

Recent advances in the treatment of pelvic malignancies in children has resulted in an increased life expectancy. In the past, treatment of soft tissue sarcomas with simple surgical excision resulted in a recurrence rate of approximately 75%. Combination of chemotherapy, radiotherapy, and surgery have significantly altered the outcome of advanced pelvic soft tissue sarcomas. With the improved survival rate of patients treated with combination therapy, sterility secondary to radiation therapy has become an issue. As little as 600 rads to the gonads may result in sterility later in life. To alleviate this problem, relocating the gonads from the field of radiation has been suggested. In this report, we present a novel approach in which the testes are wrapped in SILASTIC (Dow Corning, Midland, MI) sheaths and are relocated temporarily into the anterior abdominal wall away from the radiation field. This alternative surgical approach should be considered in boys who are afflicted with a pelvic/perineal malignancy requiring radiation therapy.

Outcome after recannulation and a second course of extracorporeal membrane oxygenation.

BACKGROUND/PURPOSE: Controversy surrounds the justification of a second course of extracorporeal membrane oxygenation (ECMO) for patients that deteriorate after initial decannulation. The authors' experience with a small number of patients requiring recannulation led them to investigate the results of a second ECMO course from all institutions that report to the ELSO registry. METHODS: The ELSO neonatal registry for patients that underwent multiple ECMO courses was reviewed and mortality and complication rates between first and second courses were compared. Complications were classified according to the following ELSO registry defined categories: hemorrhagic, mechanical, metabolic, infectious, renal, pulmonary, neurologic, and cardiac. RESULTS: Of the 16,450 patients in the ELSO neonatal registry in January 2000, 205 patients (1.25%) have required multiple ECMO courses. There have been 201 patients (1.22%) who have needed 2 courses of ECMO and 4 patients (0.024%) have undergone 3 ECMO runs. A total of 557 complications occurred during the first ECMO course in these 205 patients, and 672 complications developed during the second course. This represents an increase in the complication rate by 20.6% during the second ECMO course. Although mechanical complications were the most common, there was no change in the incidence between first and second courses. However, the frequency of complications increased in all other classifications during the second course when compared with the first. The largest increases occurred with neurologic and infectious complications (134% and 79% increases, respectively). Renal and metabolic complications also were markedly elevated (35% and 24%, respectively). Seventy-six of 201 (38%) patients who required 2 courses of ECMO and 1 of 4 patients undergoing 3 runs survived. Survival was more likely for patients with meconium aspiration. Primary pulmonary hypertension and total anomalous pulmonary venous return had low survival rates. CONCLUSIONS: A small subset of patients may require recannulation and a second ECMO course. Although survival may be achieved in more than one third of these patients, complication rates are increased during the second course. Specifically, neurologic, infectious, renal, and metabolic complication rates are increased. Long-term consequences of recannulation are unknown. Selection criteria identifying patients that may benefit from recannulation have not been established.

Application of the principles of myotomy and strictureplasty for treatment of esophageal strictures.

BACKGROUND/PURPOSE: Strictures of the esophagus in the pediatric population may be congenital or acquired. Regardless of the etiology, the treatment goal is to relieve the symptoms and allow patients to eat normally. The cornerstone of nonoperative management is repeated esophageal dilatations. However, when nonoperative management fails, operative intervention becomes necessary. In this report the authors present 4 cases of severe upper esophageal strictures managed by applying the principles of myotomy and strictureplasty. METHODS: Retrospective review of 4 patients undergoing esophageal stricturotomy from January 1, 1993 to January 1, 2000 was conducted at Childrens Hospital Los Angeles, with a mean follow-up period of 5 years. RESULTS: Three of the 4 patients reported in this report are doing well and have not required any further surgical intervention. One patient in whom additional strictures developed has had a microvascularized free jejunal graft and also is doing well. CONCLUSIONS: Currently accepted surgical management of strictures includes resection of the affected segment with end-to-end anastomosis or esophageal replacement. The authors propose that before embarking on a long and technically hazardous operation, consideration should be given to stricturotomy. In cases of isolated strictures, this may be the preferred approach.

Diagnóstico precóz de la pancreatitis aguda biliar: valor de la ecografía comparada con la clínica / Early diagnósis of acute biliary pancreatitis: value of the echography compared with the clinical

En el presente esutdio se evalúa la exactitud de los signos clínicos y exámenes de laboratorio comparándolos con la ecografía, para establecer un diagnóstico correcto de pancreatitis aguda biliar durante sus etapas tempranas. En 32 pacientes con dolor epigástrico y signos de obstrucción biliar con elevación de la amilasa, bilirrubina y fosfatasa alcalina séricas de no más de 36 hs de evolución, se formuló el diagnóstico de pancreatitis aguda por cálculo impactado en la ampolla. A todos los pacientes se les practicó ecografía del páncreas, vía biliar y vesícula biliar, entre 5 y 48 hs (X + 34 hs) después del comienzo de la sintomatología. En 12 pacientes se observaron alteraciones ecográficas del páncreas tales como agrandamiento, disminución de la ecogenicidad o ambas; en 4 pacientes se observaron alteraciones de la vía biliar y en 30 patología vesciular, particularmente litiasis. Sobre la base del diagnóstico clínico a todos los pacientes se les efectuó laparatomía entre 2 y 15 hs (X = 8 hs) después de la ecografía. En la totalidad de los casos se constataron lesiones características de pancreatitis aguda asociada con litiasis biliar; en 27 pacientes (84%) se observó bloqueo ampular litiásico presente o reciente. La exactitud del diagnóstico clínico y bioquímico de pancreatitis aguda biliar, fue del 100%. La ecografía mostró baja sensibilidad y escasa precisión para revelar las alteraciones pancreáticas y de la vía biliar durante las etapas iniciales, pero resultó un método sensible y exacto de diagnóstico de litiasis vesicular asociada en los períodos iniciales de la pacreatitis aguda (97%)

Diagnóstico precóz de la pancreatitis aguda biliar: valor de la ecografía comparada con la clínica / Early diagnósis of acute biliary pancreatitis: value of the echography compared with the clinical

En el presente esutdio se evalúa la exactitud de los signos clínicos y exámenes de laboratorio comparándolos con la ecografía, para establecer un diagnóstico correcto de pancreatitis aguda biliar durante sus etapas tempranas. En 32 pacientes con dolor epigástrico y signos de obstrucción biliar con elevación de la amilasa, bilirrubina y fosfatasa alcalina séricas de no más de 36 hs de evolución, se formuló el diagnóstico de pancreatitis aguda por cálculo impactado en la ampolla. A todos los pacientes se les practicó ecografía del páncreas, vía biliar y vesícula biliar, entre 5 y 48 hs (X + 34 hs) después del comienzo de la sintomatología. En 12 pacientes se observaron alteraciones ecográficas del páncreas tales como agrandamiento, disminución de la ecogenicidad o ambas; en 4 pacientes se observaron alteraciones de la vía biliar y en 30 patología vesciular, particularmente litiasis. Sobre la base del diagnóstico clínico a todos los pacientes se les efectuó laparatomía entre 2 y 15 hs (X = 8 hs) después de la ecografía. En la totalidad de los casos se constataron lesiones características de pancreatitis aguda asociada con litiasis biliar; en 27 pacientes (84%) se observó bloqueo ampular litiásico presente o reciente. La exactitud del diagnóstico clínico y bioquímico de pancreatitis aguda biliar, fue del 100%. La ecografía mostró baja sensibilidad y escasa precisión para revelar las alteraciones pancreáticas y de la vía biliar durante las etapas iniciales, pero resultó un método sensible y exacto de diagnóstico de litiasis vesicular asociada en los períodos iniciales de la pacreatitis aguda (97%) (AU)