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A residual liquid inoculum (RLI) was used to decolourise solutions of Acid Yellow 25 (AY25) and Direct Violet 51 (DV51) azo dyes. The RLI was obtained through anaerobic digestion of food waste from a university restaurant. The concentration of bacteria in the RLI was 8.45 × 107 CFU mL-1. Dye solutions (50 µg mL-1) were inoculated with the RLI (20% v/v) and incubated at room temperature. The decolourisation studies took place at microaerophilic and in-batch conditions and at pH = 2.50. Initially, the dyes were taken up from solution by biosorption; maximum colour removal was achieved after 3 hours of incubation, with 88.66% for AY25 and 77.65% of DV51. At prolonged incubation times (3-96 hours) decolourisation was mainly attributed to biodegradation of the azo solutions, with breakage of the azo bond, as detected by UV-VIS spectroscopy and Fourier transform infrared (FT-IR) analysis. Analysis of UV-VIS absorption rates of dyes showed, however, that AY25 was more readily biodegradable whereas DV51 was more recalcitrant to the action of the RLI.

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Understanding the mechanisms that influence brain excitability and synchronization provides hope that epileptic seizures can be controlled. In this scenario, non-synaptic mechanisms have a critical role in seizure activity. The contribution of ion transporters to the regulation of seizure-like activity has not been extensively studied. Here, we examined how non-synaptic epileptiform activity (NEA) in the CA1 and dentate gyrus (DG) regions of the hippocampal formation were affected by kainic acid (KA) administration. NEA enhancement in the DG and suppression in area CA1 were associated with increased NKCC1 expression in neurons and severe neuronal loss accompanied by marked glial proliferation, respectively. Twenty-four hours after KA, the DG exhibited intense microglial activation that was associated with reduced cell density in the infra-pyramidal lamina; however, cellular density recovered 7 days after KA. Intense Ki67 immunoreactivity was observed in the subgranular proliferative zone of the DG, which indicates new neuron incorporation into the granule layer. In addition, bumetanide, a selective inhibitor of neuronal Cl(-) uptake mediated by NKCC1, was used to confirm that the NKCC1 increase effectively contributed to NEA changes in the DG. Furthermore, 7 days after KA, prominent NKCC1 staining was identified in the axon initial segments of granule cells, at the exact site where action potentials are preferentially initiated, which endowed these neurons with increased excitability. Taken together, our data suggest a key role of NKCC1 in NEA in the DG.

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Statins may act on inflammatory responses, decreasing oxidative stress and also reducing brain inflammation in several brain disorders. Epileptogenesis is a process in which a healthy brain becomes abnormal and predisposed to generating spontaneous seizures. We previously reported that lovastatin could prevent neuroinflammation in pilocarpine-induced status epilepticus (SE). In this context, this study investigated the long-lasting effects of lovastatin on mRNA expression of proinflammatory cytokines (interleukin-1ß, tumor necrosis factor α, interleukin-6) and the antiinflammatory cytokine IL-10 in the hippocampus during epileptogenesis by immunohistochemistry and real time polymerase chain reaction (RT-PCR) during the latent and chronic phases in the epilepsy model induced by pilocarpine in rats. For these purposes, four groups of rats were employed: saline (CONTROL), lovastatin (LOVA), pilocarpine (PILO), and pilocarpine plus lovastatin (PILO+LOVA). After pilocarpine injection (350mg/kg, i.p.), the rats were treated with 20mg/kg of lovastatin via an esophagic probe 2h after SE onset. All surviving rats were continuously treated during 15days, twice/day. The pilocarpine plus lovastatin group showed a significant decrease in the levels of IL-1ß, TNF-α, and IL-6 during the latent phase and a decreased expression of IL-1ß and TNF-α in the chronic phase when compared with the PILO group. Moreover, lovastatin treatment also induced an increased expression of the antiinflammatory cytokine, IL-10, in the PILO+LOVA group when compared with the PILO group in the chronic phase. Thus, our data suggest that lovastin may reduce excitotoxicity during epileptogenesis induced by pilocarpine by increasing the synthesis of IL-10 and decreasing proinflammatory cytokines in the hippocampus.

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Several lines of evidence point to the modification of firing patterns and of synchronization due to gap junctions (GJs) as having a role in the establishment of epileptiform activity (EA). However, previous studies consider GJs as ohmic resistors, ignoring the effects of intense variations in ionic concentration known to occur during seizures. In addition to GJs, extracellular potassium is regarded as a further important factor involved in seizure initiation and sustainment. To analyze how these two mechanisms act together to shape firing and synchronization, we use a detailed computational model for in vitro high-K(+) and low-Ca(2+) nonsynaptic EA. The model permits us to explore the modulation of electrotonic interactions under ionic concentration changes caused by electrodiffusion in the extracellular space, altered by tortuosity. In addition, we investigate the special case of null GJ current. Increased electrotonic interaction alters bursts and action potential frequencies, favoring synchronization. The particularities of pattern changes depend on the tortuosity and array size. Extracellular potassium accumulation alone modifies firing and synchronization when the GJ coupling is null.

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Inhalational anaesthetics inhibit somatosensory evoked potentials. The present study examined the effect of nitrous oxide in anaesthetic mixture with sevoflurane on the somatosensory evoked potential in children. Forty-five patients aged between 6 months and 6 years undergoing club foot surgery were studied to verify the influence of sevoflurane alone (21 patients) and sevoflurane with nitrous oxide (24 patients) on the somatosensory evoked potential. Fractional inspired concentration of nitrous oxide and fractional end-tidal (alveolar) sevoflurane were measured to estimate the multiples and submultiples of the minimal alveolar concentration (age corrected). The somatosensory evoked potential signals were obtained by stimulation of the median nerve. Nitrous oxide (FI = 0.63 +/- 2.5) with sevoflurane caused more reduction in the amplitude of somatosensory evoked potential waves and a greater increase in the latency of somatosensory evoked potential waves in comparison with sevoflurane alone. The results show that it is possible to obtain the inhibition of somatosensory evoked potential with smaller concentrations of sevoflurane, when it is used with nitrous oxide.

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Coupling between cells of neuronal tissue can be due to electrical or chemical synapses. The molecular basis of an electrical synapse is the gap junction channel. Gap junctions have been found between neurones and glial cells, however, in some tissue their presence in the membranes of different cell types is still under discussion. In the retina of vertebrates, which is a true part of the CNS, the presence of gap junctions in the specialised glial cells of the retina, the Müller cells is not clear for chicken. Since these cells span the whole retina vertically, for some tasks, like spatial buffering of potassium, such gap junctions would not be required, in contrast to other parts of the CNS. The spatial buffering of potassium among others plays an important role in the propagation of excitation-depression waves in neuronal tissue, especially in the chicken retina. However, gap junctions could be involved in creating an electrical syncitium of glial cells, which might also contribute to excitation-depression wave propagation. In this paper we present an about complete screening of the presence of gap junctions in the chicken retina, including the proof that the Müller cells of this retina do not have gap junctions. This finding is discussed considering the highly specialised morphological structure of the Müller cells of the chicken retina, which have an extremely extended endfeet tree.

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The purpose of the authors in this article was to evaluate the effects of supplementing maternal milk with two different caloric formulas on the growth of premature newborns until they reached 40 weeks of post-conceptional age. Seventy premature infants weighing < 1750g at birth were randomized: 35 adequate for gestational age (AGA) and 35 small for gestational age received maternal milk and either a special preterm formula or a modified formula. Anthropometric measurements and clinical evaluations were used to determine the nutritional status and the postnatal growth of these infants, who were analyzed in six different moments: at maximum weight loss, at return to birth weight, at definite weight gain, when exclusively fed with formula, at 2000g, and when they reached 40 weeks of post-conceptional age. The AGA premature newborns on preterm formula had greater daily weight gain, cephalic circumference increase and growth. The SGA premature newborns on preterm formula had greater daily weight gain and cephalic circumference increase observed from the third week of life onward. The AGA premature newborns on modified formula had less weight gain and smaller increments in the cephalic circumference. The SGA premature on modified formula had the worst anthropometric results. The preterm formula was more efficient than the modified formula in promoting postnatal growth of AGA and SGA premature infants. We believe that, due to their special characteristics, SGA premature should receive individualized nutritional caloric planning

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UNLABELLED: Choledochoduodenostomy (CDD) has been reported as a more effective treatment of CBD stones than T-tube drainage but it is regarded as a last resort or obsolete therapeutic method due to fears of higher mobidity, cholangitis, "sump" syndrome and liver dysfunction. We aimed to assess the aforementioned issues analyzing prospectively our experience from 1976 through Dec.92. METHODS: CDD was performed in 89 females and 36 males, aged 60 +/- 8.7 years, 26 during repeat surgery. Duct stones were the indication in 94, Sphincter of oddi (SO) dysfunction in 23 and obstructive pancreatitis nodule in 8. Peroperative liver biopsies were obtained in 44 patients. The "follow-up" schedule (> 2.5 years in 110) included clinical interview and LFT's on an yearly basis. Ultra sound (USG) was obtained every one or two years. ERC was done in 10 symptomatic patients and in 25 others for protocul purposes. Liver biopsies were taken four to nine years post surgery in 11 patients-five at relaparotomy for non-biliary causes and six percutaneously by fine needle. Ductal mucosa biopsy could safely be performed in one patient 10 years after surgery. The long-term results were classified as excellent, good, fair or poor. Poor meant the need for further invasive therapy (resurgery or EST). RESULTS: There were two operative deaths (1.6%). The long-term results (123 survivors) were considered excellent in 89, good in 22, fair in 9 and poor in three. Three patients died from unrelated causes and eight others ceased the "follow-up" evaluation three to five years post surgery. All of them were considered as having excellent or good results. A widely patient anastomosis of approximately 20 mms without mucosal inflammatory changes was documented in every patient assessed via ERC. food "debris" was detected within the distal duct of four patients yet it was easily flushed through the stoma. Normal tissue patterns were observed in all long-term liver biopsies. Likewise the ductal mucosa biopsy failed to reveal any acute or chronic inflammatory changes. CONCLUSIONS: 1) CDD is a highly effective short and long-term treatment of CBD lithiasis.2) It does not lead to bacterial or "chemical" cholangitis, to "sump" syndrome or to hepatic dysfunction, provided a wide anastomosis is accomplished.3) CDD should only be considered as obsolete after extensive, long-term, prospective, randomized assessment of laparoscopic or combined laparoendoscopic approaches have been shown to be as effective as or superior to CDD.

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Malnutrition is a frequently observed complication of total gastrectomy. Does the mode of reconstructing the alimentary tract bear part of the responsibility? We assessed our experience from January 1975 to 1992 to analyze this issue. A series of 64 total gastrectomy patients [40 men, 24 women; aged 59 +/- 11 (SD) years] were considered. Preoperative and periodic follow-up evaluations were prospectively documented: upper gastrointestinal series, endoscopic examination, complete blood count, serum and liver biochemistry profiles, serum proteins, tranferrin, serum iron and calcium, iron-binding capacity, oral glucose tolerance test, ultrasonography or computed tomography, actual and ideal body weight and performance (AJCC/UICC) assessments. Symptoms were classified by means of Cuschieri's scoring system. Esophageal mucosal changes (edema, hyperemia, erosions, ulcerations) were documented on endoscopy. There were 36 of 58 operative survivors who had no evidence of tumor recurrence and were available for long-term evaluation (12-132 months). An RY loop had been constructed in 25 patients, 5 with a Hunt pouch; 9 had an isoperistaltic jejunal interposition (IJI), 4 with a Kock pouch; and 2 had a Braun loop. A 60 to 70 cm long jejunal limb was always utilized. Statistical analyses were obtained by means of the Student t-test and the equality of medians test. Progressive malnutrition was observed in patients with the Braun (omega) loops, both patients displaying persistent esophagitis and dietary restrictions. Both recovered ideal body weight after remedial surgery that transformed the omega loop into an RY loop. Both RY and IJI loops effectively prevented alkaline esophagitis.(ABSTRACT TRUNCATED AT 250 WORDS)

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Progressive malnutrition has been reported as a long-term consequence of total gastrectomy (TG), possibly related to the mode of reconstructing the intestine. In reviewing our personal experience (1975-Sept. 91), we attempted to correlate the reconstructive technique used with the subsequent course of the patient. A consecutive series of 62 TGs (59 adenocarcinomas, 3 lymphomas) in 38 males and 24 females 59 +/- 11 (m Mean +/- SD) years old was reviewed. Preoperative and "follow-up" evaluations, including upper gastrointestinal series and/or endoscopic examination, complete blood count, serum and liver biochemistry profiles, serum iron and plasma transferrin, oral GTT, USG or CT scan, actual and ideal body weight (IBW Life Extension Institute of New York), and "performance status" assessments, were prospectively documented. The follow-up symptoms were classified as per Cuschieri's scoring system. The endoscopic esophageal mucosa assessments were documented as well. Among 56 patients surviving operation, 34 were available, without tumor recurrence, for long-term (12-132 months) evaluation. A Roux-en-Y loop reconstruction had been performed in 23, 5 with a Hunt-Lawrence pouch; an isoperistaltic, esophagoduodenal, jejunal interposition (IR) was performed in 9, 4 with a Kock pouch; and an omega loop reconstruction was performed in 2. A 60-70-cm-long jejunal limb was always utilized.(ABSTRACT TRUNCATED AT 250 WORDS)

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The occurrence of retained/recurrent calculi after primary CBDE followed by temporary T-tube decompression, have remained at rates varying from 5.4% to 20.9% over the last 10 years in spite of sophisticated pre and intraoperative imaging techniques. It is postulated that a functional obstruction, due to dysmotility of the SO, lies behind most stone-containing ducts. Thus it seems logical to us that a permanent "fenestration" should be the management of most such ducts. We prospectively followed-up, for one to 10 years, two groups of patients submitted to primary CBDE aiming to assess the short and long-term results of two different surgical approaches to duct lithiasis. In one (Group A) 162 CBDE's were performed, out of 680 CHE's (24%), with a "positivity" of 68% and in the other (Group B) 80 CBDE's, out of 438 CHE's (18%), with a "positivity" of 70%. In Group A a T-tube decompression was used in 79(49%) and a definitive drainage in 83(51%) whereas in Group B the T-tube was employed in only 3(4%) and some form of permanent "fenestration" in 77(96%). There were no significant differences between the operative mortality rates, which were 2.5% in Group A (1 death post T-tube, 3 post CDJ) and 1.3% in Group B (1 death post CDD). The long-term results, though, were significantly worse among patients of Group A whose ducts were temporarily decompressed: 10/79 (12.7%) required further aggressive interventional therapy for retained/recurrent stones while only 3.8% (3/80) in Group A and 1.3% (1/76) in Group B required revisional surgery for bilio-digestive anastomotic complications with cholangitis. It is concluded that it is against the long-term efficiency of the approach utilized in Group B that the new laparoscopic techniques should be compared.

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An adaptation for clinical purposes of a radial immune hemolysis test for the detection of the heat-labile (LT) enterotoxin of the enterotoxigenic Escherichia coli is described. The results correlated well with those from Vero cell assay and the passive immune hemolysis test. Because the test is easy, relatively cheap, and as sensitive as other standard procedures, for LT detection, it is particularly suitable for less-equipped laboratories. Also, a large number of E. coli strains may be examined daily by this technique.

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