Heavy atom enhanced room-temperature phosphorimetry for ultratrace determination of harmane

Harmane has been proposed for the treatment of epilepsy, AIDS and leshmaniosis. Its room-temperature phosphorescence was induced using either AgNO3 or TlNO3, enabling absolute limits of detection of 0.12 and 2.4 ng respectively, with linear dynamic ranges extending up to 456 ng (AgNO3) and 911 ng (TlNO3). Relative standard deviations around 3% were observed for substrates containing 46 ng of harmane. Such sensitivity and precision are needed because harmane intake must be strictly controlled to achieve proper therapeutic response. Interference studies were performed using thalidomide, reserpine and yohimbine. Recovery of 104±6% was achieved using solid surface room-temperature phosphorimetry. The result was comparable to the one obtained by micellar electrokinetic chromatography.

Aplicação da cromatografia gasosa bidimensional abrangente com microdetector de captura de elétrons para determinação de agrotóxicos em sedimentos

Analysis of seven pesticides in sediments was successfully achieved using comprehensive two-dimensional gas chromatography with micro-electron capture detection, as it provided higher sensitivity and less matrix interference. Repeatability and intermediate precision of peak areas and heights were less than 4% and the recovery percentage for the analytes ranged from 52 to 115%. Instrumental LOD and LOQ were in the range of 0.60 to 2.31 μg L-1 and 1.83 to 5.62 μg L-1, respectively. Concentrations of 3.34 μg kg-1 (dry basis) for trifloxystrobin and azoxystrobin (below the LOQ) were found in a sediment sample.

Validation of a spectrophotometric method to estimate the adsorption on nanoemulsions of an antimalarial oligonucleotide

This study describes the validation of a spectrophotometric method to estimate oligonucleotides association with cationic nanoemulsions. Phosphodiester and phosphorothioate oligonucleotides targeting Plasmodium falciparum topoisomerase II were analyzed at 262 nm. Linear response (r > 0.998) was observed from 0.4 to 1.0 nmol/mL, the relative standard deviation values for the intra- and inter-days precision were lower than 2.6% and the recovery ranged from 98.8 to 103.6% for both oligonucleotides. The association efficiency was estimated based on an ultrafiltration/centrifugation method. Oligonucleotides recovery through 30 kDa-membranes was higher than 92%. The extent of oligonucleotides association (42 to 98%) varied with the composition of nanoemulsions

Quantification of tryptophan in plasma by high performance liquid chromatography

A simple, rapid and selective method using high-performance liquid chromatography with ultraviolet detection (267 nm) was applied for the determination of tryptophan in plasma. Separation was carried out on a C18 column (150 x 4.6 mm internal diameter) in 6 min. The mobile phase consisted of 5 mM the sodium acetate and acetonitrile (92:8, v/v). The method was shown to be precise and accurate, and good recovery of analyte was achieved, characterizing the method as efficient and reliable for use in laboratory analysis.

Determinação rápida de hidroquinona usando análise por injeção em batelada (BIA) com detecção amperométrica

A fast analytical method for determination of hydroquinone in pharmaceutical formulations employing batch injection analysis (BIA) with amperometric detection using a boron-doped diamond electrode is described. The supporting electrolyte was a 0.1 mol L-1 H2SO4 solution (the single reagent used for analysis). The method showed good repeatability (RSD of 0.45%, n=20), wide linear range (from 10 to 2000 µmol L-1, R=0.9999), low detection limit (0.016 µmol L-1) and satisfactory recovery values (91-96%). Accuracy of the method was evaluated by comparative analyses using high-performance liquid-chromatography. The ability to replace the electronic pipette by disposable syringes (injection procedure) in BIA systems was also shown.

Primary metabolite mobilization during germination in rosewood (Aniba rosaeodora Ducke) seeds

This study aimed to characterize protein, oil, starch and soluble sugar mobilization as well as the activity of alpha-amylase during rosewood seed germination. Germination test was carried out at 25°C and the following parameters were analyzed: percentage of germination, initial, average, and final germination time. Seed reserve quantification was monitored in quiescent seeds and during different stages of radicle growth. Starch mobilization was studied in function of a-amylase activity. Germination reached 87.5% at the initial, average, and final time of 16, 21 and 30 days, respectively. Oil mobilization showed a negative linear behavior, decreasing 40% between the first and the last stage analyzed, whereas protein levels increased 34.7% during the initial period of germination. Starch content (46.4%) was the highest among those of the metabolites analyzed and starch mobilization occurred inversely to the observed for soluble sugars; alpha-amylase activity increased until the 15th day, a period before radicle emission and corresponding to the highest starch mobilization. The high percentage of rosewood seed germination may be related to the controlled condition used in the germination chamber as well as to high seed reserve mobilization, in special oil and starch.

HYDROPHOBIC MEMBRANE TECHNOLOGY FOR AMMONIA EXTRACTION FROM WASTEWATERS

ABSTRACT Total Ammoniacal Nitrogen - TAN (NH3 + NH4+) in wastewaters cause environmental degradation concerns due to their negative impacts on air, soil and water. Several technologies are available for TAN removal from the wastewaters. One emerging technology is the use of hydrophobic membrane as non-destructive NH3 extraction. In this paper the authors discuss the uses of gas permeable membrane (GPM) and its physicochemical characteristics that influence gas mass transfer rate, diffusion and recovery mechanisms of NH3 from liquid sources (e.g. animal wastewater). Several aspects of NH3 extraction from liquid manure and other TAN generation sources using GPM technology as well as its applicability for NH3 mitigation from liquid effluents and possible recovery as a nutrient for plant growth are also discussed in this review.

Leiomiomas do esôfago removidos por vídeo-toracoscopia

This report describes three cases of esophageal leiomyomas successfully resected by thoracoscopy. Surgical enucleation through minimally invasive surgery is the treatment of choice for esophageal leiomyoma. The conventional approach through a formal thoracotomy has the potential of causing excessive pain and patient discomfort. Moreover, the hospital stay and the recovery period are prolonged. Indications for surgery were based mainly on the size of the mass (<4 cm) and the presence of dysphagia. In one case there was a clear suspicion of malignancy. The tumour was located in the lower thoracic esophagus (case 1), in the middle thoracic esophagus (case 2) and in the upper esophagus (case 3). The CT was useful in identifying the relationship between the lesion and the organs of the mediastinum. The barium swallow study was able to locate the lesion along the esophagus. The endosonography determined the boundaries of the lesions. A right thoracoscopic approach was undertaken. Dissection of the esophagus around its entire perimeter was never necessary because all tumours were anterior or right sided. The tumours were better grasped with a traction suture than with forceps. The hidrodissection was very helpful. The water-soluble contrast swallow, performed on the fourth postoperative day, was normal. Clinical results were satisfactory in all patients. Biopsies should never be performed when the mucosa overlying is normal.

O uso do tubo colônico bipediculado microcirúrgico na reconstrução do esôfago

In some cases of esophageal reconstruction, it is not possible to use the gastric tube. In those cases, the second option is the reconstruction with a colonic segment. In the present paper, the authors present the use of microsurgical technique to improve vascular supply in esophageal reconstructions using the colon. Therefore, the transposed segment becomes perfused by two vascular pedicles: a proximal one and a distal one. The authors describe a case of 52 years-old patient, suffering of middle third esophagus carcinoma, who underwent a primarily esophageal resection with an unsuccessful reconstruction using gastric transposition. A new reconstruction was proposed using a bipedicle microcirurgical colonic tube, four months later. The post operative was uneventful with rehabilitation of swallowing and satisfactory recovery of nutritional state.

Diurnal changes in storage carbohydrate metabolism in cotyledons of the tropical tree Hymenaea courbaril L. (Leguminosae)

The cotyledons of Hymenaea courbaril store large amounts of xyloglucan, a cell wall polysaccharide that is believed to serve as storage for the period of seedling establishment. During storage mobilisation, xyloglucan seems to be degraded by a continuous process that starts right after radicle protrusion and follows up to the establishment of photosynthesis. Here we show evidence that events related to the hydrolases activities and production (α-xylosidase, β-galactosidase, β-glucosidase and xyloglucan endo-β-transglucosilase) as well as auxin, showed changes that follow the diurnal cycle. The period of higher hydrolases activities was between 6pm and 6am, which is out of phase with photosynthesis. Among the enzymes, α-xilosidase seems to be more important than β-glucosidase and β-galactosidase in the xyloglucan disassembling mechanism. Likewise, the sugars related with sucrose metabolism followed the rhythm of the hydrolases, but starch levels were shown to be practically constant. A high level of auxin was observed during the night, what is compatible with the hypothesis that this hormone would be one of the regulators of the whole process. The probable biological meaning of the existence of such a complex control mechanism during storage mobilisation is likely to be related to a remarkably high level of efficiency of carbon usage by the growing seedling of Hymenaea courbaril, allowing the establishment of very vigorous seedlings in the tropical forest.

Purification of bovine pancreatic glucagon as a by-product of insulin production

A process for purifying bovine pancreatic glucagon as a by-product of insulin production is described. The glucagon-containing supernatant from the alkaline crystallization of insulin was precipitated using ammonium sulfate and isoelectric precipitation. The isoelectric precipitate containing glucagon was then purified by ion-exchange chromatography on Q-Sepharose FF, gel filtration on Sephadex G-25 and ion-exchange chromatography on S-Sepharose FF. A pilot scale test was performed with a recovery of 87.6% and a purification factor of 8.78 for the first chromatographic step, a recovery of 75.1% and a purification factor of 3.90 for the second, and a recovery of 76.2% and a purification factor of 2.36 for the last one. The overall yield was 50%, a purification factor of 80.8 was obtained and the fraction containing active glucagon (suitable for pharmaceutical preparations) was 84% pure as analyzed by HPLC

Amifostine (WR-2721), a cytoprotective agent during high-dose cyclophosphamide treatment of non-Hodgkin's lymphomas: a phase II study

Clinical trials indicate that amifostine may confer protection on various normal tissues without attenuating anti-tumor response. When administered prior to chemotherapy or radiotherapy, it may provide a broad spectrum of cytoprotection including against alkylating drugs. The mechanism of protection resides in the metabolism at normal tissue site by membrane-bound alkaline phosphatase. Toxicity of this drug is moderate with hypotension, nausea and vomiting, and hypocalcemia being observed. We report a phase II study using amifostine as a protective drug against high-dose cyclophosphamide (HDCY) (7 g/m2), used to mobilize peripheral blood progenitor cells (PBPC) and to reduce tumor burden. We enrolled 29 patients, 22 (75.9%) affected by aggressive and 7 (24.1%) by indolent non-Hodgkin's lymphoma (NHL), who were submitted to 58 infusions of amifostine and compared them with a historical group (33 patients) affected by aggressive NHL and treated with VACOP-B followed by HDCY. The most important results in favor of amifostine were the reduction of intensity of cardiac, pulmonary and hepatic toxicity, and a significant reduction of frequency and severity of mucositis (P = 0.04). None of the 29 patients died in the protected group, while in the historical group 2/33 patients died because of cardiac or pulmonary toxicity and 2 patients stopped therapy due to toxicity. Amifostine did not prevent the aplastic phase following HDCY. PBPC collection and hematological recovery were adequate in both groups. The number of CFU-GM (colony-forming units-granulocyte/macrophage) colonies and mononuclear cells in the apheresis products was significantly higher in the amifostine group (P = 0.02 and 0.01, respectively). Side effects were mild and easily controlled. We conclude that amifostine protection should be useful in HDCY to protect normal tissues, with acceptable side effects.

Effects of submaximal exercise with water ingestion on intraocular pressure in healthy human males

The effects of exercise and water replacement on intraocular pressure (IOP) have not been well established. Furthermore, it is not known whether the temperature of the fluid ingested influences the IOP response. In the present study we determined the effect of water ingestion at three temperatures (10, 24 and 38ºC; 600 ml 15 min before and 240 ml 15, 30 and 45 min after the beginning of each experimental session) on the IOP of six healthy male volunteers (age = 24.0 ± 3.5 years, weight = 67.0 ± 4.8 kg, peak oxygen uptake (VO2peak) = 47.8 ± 9.1 ml kg-1 min-1). The subjects exercised until exhaustion on a cycle ergometer at a 60% VO2peak in a thermoneutral environment. IOP was measured before and after exercise and during recovery (15, 30 and 45 min) using the applanation tonometry method. Skin and rectal temperatures, heart rate and oxygen uptake were measured continuously. IOP was similar for the right eye and the left eye and increased post-water ingestion under both exercising and resting conditions (P<0.05) but did not differ between resting and exercising situations, or between the three water temperatures. Time to exhaustion was not affected by the different water temperatures. Rectal temperature, hydration status, heart rate, oxygen uptake, carbon dioxide extraction and lactate concentration were increased by exercise but were not affected by water temperature. We conclude that IOP was not affected by exercise and that water ingestion increased IOP as expected, regardless of water temperature.

The role of the vagus nerve in hypertonic resuscitation of hemorrhagic shocked dogs

Previous studies have suggested a critical role for the vagi during the hypertonic resuscitation of hemorrhagic shocked dogs. Vagal blockade prevented the full hemodynamic and metabolic recovery and increased mortality. This interpretation, however, was challenged on the grounds that the blockade also abolished critical compensatory mechanisms and therefore the animals would die regardless of treatment. To test this hypothesis, 29 dogs were bled (46.0 ± 6.2 ml/kg, enough to reduce the mean arterial pressure to 40 mmHg) and held hypotensive for 45 min. After 40 min, vagal activity was blocked in a reversible manner (0ºC/15 min) and animals were resuscitated with 7.5% NaCl (4 ml/kg), 0.9% NaCl (32 ml/kg), or the total volume of shed blood. In the vagal blocked isotonic saline group, 9 of 9 dogs, and in the vagal blocked replaced blood group, 11 of 11 dogs survived, with full hemodynamic and metabolic recovery. However, in the hypertonic vagal blocked group, 8 of 9 dogs died within 96 h. Survival of shocked dogs which received hypertonic saline solution was dependent on vagal integrity, while animals which received isotonic solution or blood did not need this neural component. Therefore, we conclude that hypertonic resuscitation is dependent on a neural component and not only on the transient plasma volume expansion or direct effects of hyperosmolarity on vascular reactivity or changes in myocardial contraction observed immediately after the beginning of infusion.

Response of the arterial blood pressure of quadriplegic patients to treadmill gait training

Blood pressure pattern was analyzed in 12 complete quadriplegics with chronic lesions after three months of treadmill gait training. Before training, blood pressure values were obtained at rest, during treadmill walking and during the recovery phase. Gait training was performed for 20 min twice a week for three months. Treadmill gait was achieved using neuromuscular electrical stimulation, assisted by partial body weight relief (30-50%). After training, blood pressure was evaluated at rest, during gait and during recovery phase. Before and after training, mean systolic blood pressures and heart rates increased significantly during gait compared to rest (94.16 ± 5.15 to 105 ± 5.22 mmHg and 74.27 ± 10.09 to 106.23 ± 17.31 bpm, respectively), and blood pressure decreased significantly in the recovery phase (86.66 ± 9.84 and 57.5 ± 8.66 mmHg, respectively). After three months of training, systolic blood pressure became higher at rest (94.16 ± 5.15 mmHg before training and 100 ± 8.52 mmHg after training; P < 0.05) and during gait exercise (105 ± 5.22 mmHg before and 110 ± 7.38 mmHg after training; P < 0.05) when compared to the initial values, with no changes in heart rate. No changes occurred in blood pressure during the recovery phase, with the lower values being maintained. A drop in systolic pressure from 105 ± 5.22 to 86.66 ± 9.84 mmHg before training and from 110 ± 7.38 to 90 ± 7.38 mmHg after training was noticed immediately after exercise, thus resulting in hypotensive symptoms when chronic quadriplegics reach the sitting position from the upright position.