Evaluation of genotoxic potential of peptides used in nuclear medicine (PSMA -617 and -11, and ubiquicidine 29-41) using a flow-cytometric, semi-automated analysis of micronuclei frequency in cell cultures.

Assays that rely on the assessment of frequency of micronuclei are important standard techniques currently used to quantify potential genotoxic damage after exposure to chemical or physical agents, such as ionizing radiation, or in pre-clinical studies, to assessment of the genotoxic potential of drugs or its components. The experiments are usually performed using conventional microscopy, but currently the protocols are being upgraded to automated approaches based on flow cytometry protocols based on the elimination of the plasma membrane by chemical agents, allowing quantification by flow cytometry. In this work, the genotoxic potential of peptides used as components of radiopharmaceuticals (PSMA-617 and 11 and Ubiquicidine) was evaluated exposing CHO-KI cells to a wide range of concentration (0.1X and 100X the maximum allowed concentration to human adults). Incubation with PSMA-11 or UBI29-41 did not induce genotoxicity. After 24 h of incubation, PSMA-617 induced genotoxicity only in non-practical concentration (100-fold). Results corroborate the safety of the pre-drugs and the wide detection range of technique.

Effects of Ischemic Preconditioning and Postconditioning in a Renal Ischemia-Reperfusion Injury Model: A Comparative Experimental Study in Rats.

BACKGROUND: Ischemia-reperfusion injury is an unavoidable aspect of transplantation, as well as an important cause of acute kidney injury in clinical practice. Pre- and post-ischemic conditioning are strategies that may provide organs with resistance to major ischemic events. This study evaluates the effects of ischemic preconditioning and ischemic postconditioning, either separately or in combination, after an acute ischemia-reperfusion kidney injury. METHODS: Forty Wistar rats received isoflurane anesthesia and were randomized into 5 groups: 1. the sham group underwent laparotomy; 2. the control group underwent laparotomy and 30 minutes of renal ischemia followed by reperfusion; 3. the preconditioning group underwent laparotomy, ischemic preconditioning, and 30 minutes of renal ischemia followed by reperfusion; 4. the preconditioning and postconditioning group underwent laparotomy, ischemic preconditioning, 30 minutes of renal ischemia, and ischemic postconditioning followed by reperfusion; and 5. the postconditioning group underwent laparotomy, 30 minutes of renal ischemia, and ischemic postconditioning followed by reperfusion. Serum analyses of creatinine and neutrophil gelatinase-associated lipocalin (NGAL) were performed, and renal histology was examined 24 hours later. RESULTS: Severe tubular injury and increases in creatinine were observed in all groups except the sham group. The control group and all ischemic conditioning groups were no different in the degree of renal injury and values of NGAL and creatinine after the injury. CONCLUSIONS: Ischemic preconditioning and ischemic postconditioning, together or separately, are unable to preserve kidney function or exert a protective effect against tubular cell injury after an acute ischemia-reperfusion kidney injury.

Voice and ageing: clinical, endoscopic and acoustic investigation.

Vocal symptoms are frequent in the elderly and are consequences of structural changes in the larynx that occur with ageing. OBJECTIVE: To identify the voice alterations in elderly patients attending a voice clinic. METHODS: Elderly patients of both genders were divided into two groups: 60-75 and above 76 years. All patients completed a questionnaire with identification data, profession, vocal symptoms, hearing, habits and addictions, and systemic diseases. All participants were submitted to video laryngoscopy and acoustic and auditory-perceptual vocal analysis. RESULTS: In this study, women predominated (40 F versus 32 M). Hoarseness was reported by 34.72% of the participants. Other symptoms included singing difficulty (17%) and phonatory effort (15.28%). Maximum phonation time showed lower values and scores 2 and 3 of perceptual analysis were registered in 33% of the elderly participants, but without statistical significance. The fundamental frequency values were inferior in older man and high in women and acoustic parameters showed high values in both groups, but without statistical significance. Videolaryngoscopies demonstrated alterations in 47% of the participants, especially bowed and atrophic vocal folds. CONCLUSIONS: We described the vocal symptoms, vocal perceptual and acoustic analysis and endoscopic findings of an elderly population, characterising the presbyphonia. Therapeutic measures must involve speech therapy and/or surgery to reduce the glottal gap, allowing less air leakage and, consequently, better vocal performance.

Evaluation of renal protection from high doses of melatonin in an experimental model of renal ischemia and reperfusion in hyperglycemic rats.

BACKGROUND: Melatonin is a free radical scavenger with important actions in the study of renal ischemia and reperfusion (I/R). This study evaluated possible renal protection of high doses of melatonin in an experimental model of I/R in which rats were submitted to acute hyperglycemia under anesthesia with isoflurane. METHOD: Forty-four male Wistar rats, weighing more than 300 g, were randomly divided into 5 groups: G1, sham (n = 10); G2, melatonin (n = 10; 50 mg.kg(-1)); G3, hyperglycemia (n = 9; glucose 2.5 g.kg(-1)); G4, hyperglycemia/melatonin (n = 10; 2.5 g.kg(-1) glucose + melatonin 50 mg.kg(-1)); and G5, I/R (n = 5). In all groups, anesthesia was induced with 4% isoflurane and maintained with 1.5% to 2.0% isoflurane. Intraperitoneal injection of melatonin (G1, G4), glucose (G3, G4), or saline (G1, G5) was performed 40 minutes before left renal ischemia. Serum plasma values for creatinine and glucose were determined at baseline (M1), immediately following reperfusion (M2), and 24 hours after completion of the experiment (M3). Histological analysis was performed to evaluate tubular necrosis (0-5). RESULTS: Serum glucose was higher at M2 in the groups supplemented with glucose, hyperglycemia (356.00 ± 107.83), and hyperglycemia/melatonin (445.3 ± 148.32). Creatinine values were higher at T3 (P = .0001) for I/R (3.6 ± 0.37), hyperglycemia/melatonin (3.9 ± 0.46), and hyperglycemia (3.71 ± 0.69) and lower in the sham (0.79 ± 0.16) and melatonin (2.01 ± 1.01) groups, P < .05. Histology showed no necrosis injury in the G1, lesion grade 2 in the G2, and severe acute tubular necrosis in the G3: (grade 4), G4: (grade 5) and G5: (grade 4) groups (P < .0001). DISCUSSION: Melatonin protected the kidneys submitted to I/R in rats without hyperglycemia; however, this did not occur when the I/R lesion was associated with hyperglycemia. CONCLUSIONS: Due to its antioxidant and antiapoptotic action, melatonin was able to mitigate, but not prevent acute tubular necrosis in rats with hyperglycemia under anesthesia by isoflurane.

Comparison of peri-operative core temperature in obese and non-obese patients.

Our aim was to compare peri-operative core temperatures and the incidence of hypothermia in obese and non-obese women with active forced-air warming. Twenty female patients scheduled for abdominal surgery were allocated to two groups according to body mass index. Ten obese (30.0-34.9 kg.m(-2) ) and 10 non-obese (18.5-24.9 kg.m(-2) ) women received forced-air warming on their lower limbs. At the end of surgery, the mean (SD) core temperatures were 36.7 (0.5) °C in the obese group and 36.0 (0.6) °C in the non-obese group (p < 0.001). Only in the non-obese group was there a significant decrease in the intra-operative core temperature values (p < 0.001). The incidences of intra-operative hypothermia were lower in the obese group (10%) compared with non-obese group (60%; p = 0.019). In the postoperative recovery phase, the mean (SD) core temperature data were higher in the obese group than in the non-obese group (36.2 (0.4) vs 35.6 (0.5) °C, respectively (p < 0.001)). In conclusion, obese female patients have higher peri-operative core temperature and a lower incidence of hypothermia compared with non-obese female patients during abdominal surgery with active forced-air warming.

Accuracy of routine diagnostic tests used in paracoccidioidomycosis patients at a university hospital.

The identification of appropriate laboratory measures to confirm clinical hypotheses is important in routine paracoccidioidomycosis medical care. The clinical records and laboratory reports of 401 paracoccidioidomycosis patients attended at the Tropical Diseases Area, Faculdade de Medicina de Botucatu, from 1974 to 2008 were reviewed. Direct mycological (DM), cell block (CB), histopathological (HP), and double immunodiffusion (DID) tests were evaluated before treatment. Typical Paracoccidioides brasiliensis yeast forms were observed in clinical specimens of 86% of the patients, but 14% were detected only by serological test. DM of 51 different tissue specimens produced 74.5% sensitivity, and 62.5% sensitivity was observed in 112 sputum samples. CB in 483 sputum samples generated 55.3% sensitivity. HP performed in 239 samples from different tissues revealed 96.7% sensitivity. Serology carried out in 351 patients and 200 healthy controls provided 90.0% sensitivity, 100.0% specificity, 100.0% positive predictive value, 85.1% negative predictive value and 93.6% accuracy. Comparisons of laboratory measurements performed in the same patient showed that sensitivity decreases from HP to DID to CB and DM, with the last two assays providing similar sensitivities. This study demonstrated that P. brasiliensis identification by HP, CB, and/or DM associated with DID is sufficient to establish the laboratorial diagnosis of paracoccidioidomycosis in practically all cases.

Evaluation of hemodynamic, metabolic, and electrolytic changes after graft reperfusion in a porcine model of intestinal transplantation.

BACKGROUND: We sought to establish an anesthetic protocol to evaluate the hemodynamic, metabolic, and electrolytic changes after graft reperfusion in pigs undergoing orthotopic intestinal transplant (ITx). METHODS: Fifteen pigs were distributed into two groups: GI (n = 6), without immunosuppression, and GII (n = 9), immunosuppressed before surgery with tacrolimus (0.3 mg/kg). The animals were premedicated at 1 hour before surgery with IM acepromazine (0.1 mg/kg), morphine (0.4 mg/kg), ketamine (10 mg/kg), and atropine (0.044 mg/kg IM). Anesthesia induction used equal proportions of diazepam and ketamine (0.1-0.15 mL/kg/IV) and for maintenance in IV infusion of xylazine (1 mg/mL), ketamine (2 mg/mL), and guaiacol glyceryl ether 5% (50 mg/mL), diluted in 250 mL of 5% glucose solution. In addition, recipient pigs were treated with isofluorane inhalation. Heart rate (HR), systolic (SAP), mean (MAP), and diastolic (DAP) arterial pressure, pulse oximetry, respiratory frequency (f), capnography, body temperature (T), blood gas analysis (pH, Paco(2), Pao(2), base excess, BE; Hco(3)(-), Sato(2)), serum potassium (K), calcium (Ca), sodium, hematocrit (Hct), and glucose (Glu) were measured at four times; M0: after incision (basal value); M1: 10 minutes before reperfusion; and M2 and M3: 10 and 20 minutes after graft reperfusion. RESULTS: All groups behaved in a similar pattern. There was significant hypotension after graft reperfusion in GI and GII (M2 = 56.2 +/- 6.4 and M3 = 57.2 +/- 8.3 mm Hg and M2 = 65.7 +/- 10.2 and M3 = 67.8 +/- 16.8 mm Hg, respectively), accompanied by elevated HR. The ETco(2) was elevated at M2 (42 mm Hg) and M3 (40 mm Hg). Metabolic acidosis was observed after reperfusion, with significant increase in K levels. CONCLUSION: The anesthetic protocol for donors and recipients was safe to perform the procedure, allowing control of hemodynamic and metabolic changes after reperfusion without differences regarding immunosuppression.

Perioperative cardiac arrest: a study of 53,718 anaesthetics over 9 yr from a Brazilian teaching hospital.

BACKGROUND: Little information exists regarding factors influencing perioperative cardiac arrests and their outcome. This survey evaluated the incidence, causes and outcome of perioperative cardiac arrests in a Brazilian tertiary general teaching hospital between April 1996 and March 2005. METHODS: The incidence of cardiac arrest during anaesthesia was prospectively identified from an anaesthesia database. There were 53,718 anaesthetics during the study period. Data collected included patient characteristics, surgical procedures (elective, urgent or emergency), ASA physical status classification, anaesthesia provider information, type of surgery, surgical areas and outcome. All cardiac arrests were retrospectively reviewed and grouped by cause of arrest and death into one of four groups: totally anaesthesia related, partially anaesthesia related, totally surgery related or totally patient disease or condition related. RESULTS: One hundred and eighty-six cardiac arrests (34.6:10,000) and 118 deaths (21.97:10,000) were found. Major risk factors for cardiac arrest were neonates, children under 1 yr and the elderly (P<0.05), male patients with ASA III or poorer physical status (P<0.05), in emergency surgery (P<0.05) and under general anaesthesia (P<0.05). Patient disease/condition was the major cause of cardiac arrest or death (P<0.05). There were 18 anaesthesia-related cardiac arrests (3.35:10,000) -- 10 totally attributed (1.86:10,000) and 8 partially related to anaesthesia (1.49:10,000). There were 6 anaesthesia-related deaths (1.12:10,000) -- 3 totally attributable and 3 partially related to anaesthesia (0.56:10,000 in both cases). The main causes of anaesthesia-related cardiac arrest were respiratory events (55.5%) and medication-related events (44.5%). CONCLUSIONS: Perioperative cardiac arrests were relatively higher in neonates, infants, the elderly and in males with severe underlying disease and under emergency surgery. All anaesthesia-related cardiac arrests were related to airway management and medication administration which is important for prevention strategies.

Genotoxicity of fractionated organic material in airborne particles from São Paulo, Brazil.

Particulate matter less than 10 microns aerodynamic diameter (PM10) is associated with adverse health effects including increased respiratory problems and mortality. PM10 is also associated with increases in cancer in some urban areas. Identification of toxic compounds in PM10 is a step toward estimating exposure to these compounds and evaluating their public health risk. However, the toxic compounds on PM10 are part of a highly complex mixture of compounds that makes chemical characterization difficult. Before this study, there has been little investigation of genotoxic compounds in particulate matter from Latin American cities. Here, both bioassay (mutagenicity) and chemical analyses were conducted with organic solvent extracts of PM10 collected from São Paulo, a major Brazilian city. Sequential extraction in dichloromethane (DCM) followed by acetone (ACE) yielded 20.3% and 10.2% of the total mass, respectively. Non-polar and moderately polar organic material solubilized in DCM. ACE extracted more polar organic species and some inorganic ions. Both extracts were fractionated separately using cyanopropyl-bonded silica chromatography with organic solvents of increasing polarity. The mass distribution among the fractions was measured. The mutagenic activity of the fractions was assayed using the microsuspension procedure with the Salmonella typhimurium tester strain TA98, with and without addition of metabolic enzymes (S9). The DCM extract had about four times higher mutagenic activity than the ACE extract. In general, addition of S9 resulted in an increase in mutagenicity of DCM fractions, but a decrease for the ACE extract. Most of the activity was concentrated in fractions in the mid-range of polarity within both the DCM and ACE extracts. The fractions were analyzed by gas chromatography with mass selective detection (GC/MS) without derivatization. The most mutagenic fractions in the DCM extract contained ketones, aldehydes, and quinolines. The most mutagenic ACE fraction had ketones, carboxylic acids, and aldehydes.

Capillary electrophoresis determination of urinary muconic acid as a biological marker for benzene in cigarette smoke.

trans,trans-Muconic acid (MA), a benzene metabolite in urine, has currently been indicated as a biological marker for benzene in cigarette smoke. The available methodologies for MA present a few shortcomings, such as lack of specificity and labor-intensive sample pretreatment. In this work, a capillary electrophoresis method for separation, identification, and quantification of urinary muconic acid has been implemented. The electrolyte consisted of a 60-mM phosphate buffer solution (pH 7), containing 0.1 mM cetyltrimethylammonium bromide (CTAB) as an electroosmotic flow modifier. Urine samples from nonsmokers and smokers were filtered through a 0.22-micron membrane prior to injection in a 75 microns i.d. x 80 cm capillary. The analysis was conducted under constant voltage conditions of -30 kV and direct UV detection at 262 nm. The detection capability of the electrophoresis system was enhanced by employing a high-sensitivity optical cell, positioned at 60 cm from the injection port. The CE methodology presented an overall analysis time of less than 10 min, with 5 min spent for capillary conditioning and approximately 5 min for run completion. The method was found to be sensitive for the determination of MA down to 25 micrograms/L, with a percentage recovery of 100 +/- 8%, and suitable for discriminating urinary MA from nonsmokers and smokers.