Analytical procedures for determining Pb and Sr isotopic compositions in water samples by ID-TIMS

Few articles deal with lead and strontium isotopic analysis of water samples. The aim of this study was to define the chemical procedures for Pb and Sr isotopic analyses of groundwater samples from an urban sedimentary aquifer. Thirty lead and fourteen strontium isotopic analyses were performed to test different analytical procedures. Pb and Sr isotopic ratios as well as Sr concentration did not vary using different chemical procedures. However, the Pb concentrations were very dependent on the different procedures. Therefore, the choice of the best analytical procedure was based on the Pb results, which indicated a higher reproducibility from samples that had been filtered and acidified before the evaporation, had their residues totally dissolved, and were purified by ion chromatography using the Biorad® column. Our results showed no changes in Pb ratios with the storage time.

Synthesis of quinoxaline 1,4-di-N-oxide derivatives on solid support using room temperature and microwave-assisted solvent-free procedures

We describe the synthesis of 12 new ethyl and methyl quinoxaline-7-carboxylate 1,4-di-N-oxide derivatives on solid supports with room temperature and microwave-assisted solvent-free procedures. Results show that solid supports have good catalytic activity in the formation of quinoxaline 1,4-di-N-oxide derivatives. We found that florisil and montmorillonite KSF and K10 could be used as new, easily available, inexpensive alternatives of catalysts. Additionally, room temperature and microwave-irradiation solvent-free synthesis was more efficient than a conventional procedure (Beirut reaction), reducing reaction time and increasing yield.

Flavonoids extraction from Alpinia zerumbet (Pers.) Burtt et Smith leaves using different procedures

The current study aims to verify the best method for a rapid and efficient extraction of flavonoids from Alpinia zerumbet. Dried leaves were extracted using distillated water and ethanol 70% by extraction methods of shaking maceration, ultrasonic, microwave and stirring. By the application of TLC and reversed-phase HPLC techniques the rutin and kaempferol-3-O-glucuronide were detected. Ethanol 70% was more efficient for flavonoids extraction than water. No significant yielding variation was verified for ultrasonic, microwave and stirring methods using ethanol 70% (11 to 14%). Relative concentration of rutin and kaempferol-3-O-glucuronide, respectively, was higher by ultrasonic (1.5 and 5.62 mg g-1 dried leaves) and by microwave (1.0 and 6.64 mg g-1 dried leaves) methods using 70% ethanol. Rapid and simplified extraction proceeding optimize phytochemical work and acquisition of secondary metabolites.

COMPARISON OF PROCEDURES FOR IMMEDIATE CHEMICAL ANALYSIS OF CHARCOAL

ABSTRACT The climate change, the quest for sustainability and the strong environmental pressures for alternatives to traditional fossil fuels have increased the interest in the search and use of renewable energy sources. Among them stands out the biomass of charcoal coming from renewable forests, widely used as a thermal reductant in the steel industry in the detriment of the use of mineral coal coke. This study aimed to compare different operating procedures of immediate chemical analysis of charcoal. Seven essays to immediate chemical analysis were compared, spread between procedures performed by Brazilian companies and laboratories, the test described by NBR 8112 and one realized with a thermogravimetric analyzer (TGA) using the parameters of the NBR 8112. There were significant differences in the volatiles matter content and consequently in the fixed carbon contents found. The differences between the procedures and the NBR 8112 were caused by an excess burning time, a mass sample above or below the standard or inappropriate container used for burning. It observed that the TGA appraisal of the volatiles content must be carried out with a burning time equal to 2 minutes to obtain results similar to those of the NBR 8112 norm. Moreover, the ash content values were statistically identical and the particles size did not influence the differences between means.

Effects of maintenance management procedures in sugarcane mechanic harvesting system equipment

ABSTRACT The aim of this study was to evaluate the effects of modifying the maintenance programming of equipment used in sugarcane mechanical harvesting, by transferring actions that can be planned to periods when machines are inactive due to meal breaks and other working shift transitions stoppages. A simulation model was developed to represent the maintenance procedures of combines, haulouts, and other vehicles used by a harvest team. Scenarios were tested using alternatives for interventions such as refueling, lubrication and harvester blade replacement, enabling strategies to be focused towards better utilization of cutting, loading, and transport (CLT) system equipment. As a result, it was possible to remove one combine and two haulouts, while maintaining current daily production. The maintenance time for harvesters, which refers to corrective maintenance and the transfer of remaining interventions for periods of inactivity, was reduced from 10.0% to 3.5% over the useful period. This study indicates that maintenance management in the sugarcane sector enables the expanded use of equipment, leading to the greater productivity of the CLT system.

Acalasia do esôfago: miotomia com transiluminação

Laparoscopic techniques have provided a new dimension to correct functional disorders of the esophagus, which has stimulated some investigators to recently report the use of laparoscopic cardiomyotomy in the treatment of esophageal achalasia. Now, a new instrument has been added to the current laparoscopic technique to offer a safer and easier method to proceed complete myotomy. After the dissection of the esophagogastric junction, a special catheter is introduced reaching the stomach. lt has an illuminated 10 cm extremity connected to a light source. lts withdrawal allows to visualize every muscle circular fiber by transillumination withan improved view provide by the laparoscopic optic system lens. This condition modifies the operative surgeon s attitude offering a better controlled situation over the procedure. The use of transillumination o fthe esophagogastric junction provides a good identification of the mucosa e submucosa avoiding the risk of esophageal perforation. It also helps to perform a complete myotomy preventing the ocurrence of persistent disphagia in the postoperative period. Cardiomyotomy with parcial fundoplication is possible by videolaparoscopic approach, now made easier with transillumination. This technique is safe and the functional results are similar to those observed in the literature for conventional open procedures, with the obvious advantages of the minimally invasive approach.

Extração de fitobezoar gástrico por videolaparoscopia: considerações técnicas originais

Videolaparoscopic surgery has been used for treatment of almost all surgical abdominal diseases, mainly where there are no large ressections, or operative field is limited. In these situations, laparoscopic surgery has the advantages of less morbidity, quick recovery and good cosmetic results. Bezoars removal, or its mobilization, is probably included in these possible proceedings. Three non-laparotomic procedures were described: 1. endoscopic-laparoscopic; 2. videolaparoscopy and mobilization of intestinal bezoar to the cecum; 3. laparoscopy and gastrotomy for bezoar removal, through suprapubic incision or the umbilical punction. There have been only two publications describing the videolaparoscopic method for bezoar removal, and the methods applied can be complications or morbidity related. We describe one case where the applied technique is simple and easy to perform, time saving and probably less complications-related. This technique, with four trocars, utilized a plastic bag besides the stomach to be opened, followed by gastrotomy, bezoar removal and immediate introduction in the plastic bag, suture of gastrotomy and removal through the left subcostal trocar. This technique was feasible and easy to perform, with short operative time, and there were no intra or post-operative complications; the patient was discharged in the second post-operative day, and is without further problems after one year follow-up. We believe that this could be an adequate technique to perform laparoscopic gastric bezoar removal, and the rigid sequence of operative events allows a quick procedure, with minimal contamination. The videolaparoscopy seems to be an adequate access to surgical treatment of gastro-intestinal bezoars, with or without obstruction, and should be the ellected the procedure of choice to begin the surgical treatment, with convertion to laparotomy in case of any intra-operative adversity.

Complicação da banda gástrica ajustável videolaparoscópica para tratamento da obesidade mórbida: extrusão da banda

Various options for surgical treatment of morbid obesity have been developed with varying results: vertical banded gastroplasty with intestinal by-pass, disabsorptive surgeries and laparoscopic adjustable gastric banding. Although all of them have been effective in weight loss, lower rates of early and late postoperative complications have been described in some procedures. Laparoscopic adjustable silicone gastric banding (LASGB) has a similar principle as vertical banded gastroplasty and it is a minimally invasive procedure, with low systemic and operative problems, but not free of them. We report two rare cases of this complications of LASGB.

Cirurgia de tikhoff-linberg para tratamento de condrossarcoma localmente avançado da região escápulo-umeral

Chondrosarcoma is a rare malignant neoplasia that most of the time affects young adults. Its location is preferentially the pelvic and scapular girdle and surgery is its treatment of choice. There are no role for chemo or radiation therapy, because of their low index of response. We describe a case of a 45 year-old male patient with an extensive low grade right umerus chondrosarcoma. In spite of the local extension, there was no invasion of the shoulder neurovascular structures. Treatment proposed was the Tikhoff-Linberg procedure, and the operation was performed with success, with no complications. Free margins were obtained. The patient is now on two years follow-up with no evidence of recurrent disease and is able to drive, fish and carry packs. He can not abduct his arm, but he could not do that even before surgery, due to severe pain. We believe this is an excellent conservative approach to such tumors, that otherwise would require a forequarter amputation, and strongly recommend the technique.

Pectus excavatum: abordagem terapêutica

The pectus excavatum treatment has two different approaches: non-surgical techniques (modified dynamic thoracic compressor, exercises and the vacuum bell) or surgical techniques (silastic or solid silicone implant, open surgical repair like sternochondroplasty and minimally invasive repair). The introduction of Nuss procedure improved the pectus excavatum treatment, but its low acceptance was due to the high complication rate (e.g. cardiac perfuration). The thoracoscopy use for bar mediastinal passage reduced the complication rate. In comparison with sternochondroplasty, the Nuss procedure has smaller incision, less blood loss and less operative time. However, it has more reoperations, complications, longer hospital stay and more readmission rates, more time of thoracic epidural catheter for postoperative analgesia and more need for analgesic after being discharged. Although Nuss procedure has been used in children, patients under ten years must be only observed. The Nuss procedure is applicable to moderate or light symmetrical pectus excavatum, without costal protrusion, in young and adolescents patients. Furthermore, the sternochondroplasty is applicable to severe or asymmetric pectus excavatum, with or without inferior costal protrusion. Therefore, Nuss procedure and sternocondroplasty are not antagonistic procedures, and they must be used in accordance with a treatment organogram and the technique choice must be by functional and aesthetic outcome.

Damage control surgery: it's evolution over the last 20 years

In less than twenty years, what began as a concept for the treatment of exsanguinating truncal trauma patients has become the primary treatment model for numerous emergent, life threatening surgical conditions incapable of tolerating traditional methods. Its core concepts are relative straightforward and simple in nature: first, proper identification of the patient who is in need of following this paradigm; second, truncation of the initial surgical procedure to the minimal necessary operation; third, aggressive, focused resuscitation in the intensive care unit; fourth, definitive care only once the patient is optimized to tolerate the procedure. These simple underlying principles can be molded to a variety of emergencies, from its original application in combined major vascular and visceral trauma to the septic abdomen and orthopedics. A host of new resuscitation strategies and technologies have been developed over the past two decades, from permissive hypotension and damage control resuscitation to advanced ventilators and hemostatic agents, which have allowed for a more focused resuscitation, allowing some of the morbidity of this model to be reduced. The combination of the simple, malleable paradigm along with better understanding of resuscitation has proven to be a potent blend. As such, what was once an almost lethal injury (combined vascular and visceral injury) has become a survivable one.

Avulsão da via biliar principal: relato de caso

Common bile duct disruption from blunt trauma is very rare. Management, diagnosis and therapy by a non-specialist surgeon can be difficult. We describe a bile duct injury after a motor vehicle crash in a young male, treated with cholecystojejunostomy at his third laparotomy. We also briefly review some diagnostic aspects and therapeutic options from the literature.

Arthroscopic treatment of refractory adhesive capsulitis of the shoulder

OBJECTIVE: to evaluate the results of arthroscopic treatment of refractory adhesive capsulitis of the shoulder associated as for improved range of motion after a minimum follow up of six years. METHODS: from August 2002 to December 2004, ten patients with adhesive capsulitis of the shoulder resistant to conservative treatment underwent arthroscopic surgery. One interscalene catheter was placed for postoperative analgesia before the procedure. All were in Phase II, with a minimum follow up of two years. The mean age was 52.9 years (39-66), predominantly female (90%), six on the left shoulder. The time between onset of symptoms and surgical treatment ranged from six to 20 months. Four adhesive capsulitis were found to be primary (40%) and six secondary (60%). RESULTS: the preoperative mean of active anterior elevation was 92°, of external rotation was 10.5° of the L5 level internal rotation; the postoperative ones were 149°, 40° and T12 level, respectively. Therefore, the average gain was 57° for the anterior elevation, 29.5° for external rotation in six spinous processes. There was a significant difference in movements' gains between the pre and post-operative periods (p<0.001). By the Constant Score (range of motion), there was an increase of 13.8 (average pre) to 32 points (average post). CONCLUSION: the arthroscopic treatment proved effective in refractory adhesive capsulitis of the shoulder resistant to conservative treatment, improving the range of joint movements of patients evaluated after a minimum follow up of six years.

Protecting the skin during thyroidectomy

In this note we describe the standard technical maneuver used in our department to protect the skin during thyroidectomy in order to get the best aesthetic result. We use surgical gloves to protect the skin during these operations to reduce the negative impact of thermal trauma and mechanical retractors and energy delivery devices at the edges of the skin incised. This practice is effective, inexpensive, rapid, reproducible and showed no complication in our experience of over 2,500 thyroidectomies.

An alternative experimental model for training in microsurgery

OBJECTIVE: to describe a new model of training in microsurgery with pig spleen after splenectomy performed by undergraduate students of the Discipline of Operative Technique of the UFPR Medical School. METHODS: after the completion of splenectomy we performed dissection of the vascular pedicle, distal and proximal to the ligation performed for removal of the spleen. After complete dissection of the splenic artery and vein with microscope, clamps were placed and the vessels were cut. We then made the anastomosis of the vessels with 9.0 nylon. RESULT: the microsurgical training with a well-defined routine, qualified supervision and using low cost experimental materials proved to be effective in the practice of initial microvascular surgery. CONCLUSION: the use of pig spleen, which would be discarded after splenectomy, is an excellent model for microsurgical training, since besides having the consistency and sensitivity of a real model, it saves the sacrifice of a new animal model in the initial learning phase of this technique.