Adriano Bonfim Carregaro

Formulation and in vivo evaluation of sodium alendronate spray-dried microparticles intended for lung delivery.

Spray-dried powders for lung delivery of sodium alendronate (SA) were prepared from hydroalcoholic solutions. Formulations display geometric particle size below to 12 μm and spherical shape associated to a hollow structure. The addition of leucine and ammonium bicarbonate leads to porous particles with rough surfaces. The tapped density ranges from 0.016 to 0.062 g/cm(3), decreasing with the increase of the leucine concentration. For all formulations, the calculated aerodynamic diameters are lower than 5 μm. The in vitro aerodynamic evaluation shows that all powders present a high emitted fraction of 100%, a fine particle fraction ranging from 34.4% to 62.0% and an alveolar fraction ranging from to 23.7% to 42.6%. An optimized sample was evaluated regarding sodium alendronate acute pulmonary toxicity and lung bioavailability. The bronchoalveolar lavage study shows that the intratracheal administration of sodium alendronate dry powder and sodium alendronate aqueous solution do not induce significant increases of lung toxicity indicators as compared with the positive control. Moreover, the intratracheal administration of sodium alendronate dry powder results in a 6.23 ± 0.83% bioavailability, a 3.5-fold increase as compared to oral bioavailability. Finally, these results suggest that sodium alendronate pulmonary delivery could be a new and promising administration route.

Renal and cardiorespiratory effects of treatment with lactated Ringer's solution or physiologic saline (0.9% NaCl) solution in cats with experimentally induced urethral obstruction.

OBJECTIVE To compare the renal and cardiorespiratory effects of IV treatment with lactated Ringers solution (LRS) or physiologic saline (0.9% NaCl) solution (PSS) in severely decompensated cats with urethral obstruction (UO). ANIMALS 14 cats (4 cats were used only to establish infusion rates). PROCEDURES An occluded urethral catheter was used to induce UO in each cat. After development of severe metabolic acidosis, hyperkalemia, and postrenal azotemia, the obstruction was relieved (0 hours); LRS or PSS (5 cats/group) was administered IV (gradually decreasing rate) beginning 15 minutes before and continuing for 48 hours after UO relief. Ten minutes before urethral catheter placement (baseline), at start of fluid therapy (SFT), and at intervals during fluid administration, various physical and clinicopathologic evaluations were performed. RESULTS Metabolic acidosis was detected in the PSS-treated group at SFT and 2 hours after relief of UO and in the LRS-treated group only at SFT The PSS-treated group had significantly lower blood pH and bicarbonate concentrations at 8 through 48 hours and lower base excess values at 2 through 48 hours, compared with the LRS-treated group. Hypocalcemia and hypernatremia were detected in the PSS-treated group at 2 and 12 hours, respectively. Absolute serum potassium and chloride concentrations did not differ significantly between groups at any time point. CONCLUSIONS AND CLINICAL RELEVANCE Treatment with LRS or PSS appeared to be safe and effective in cats with experimentally induced UO; however, LRS was more efficient in restoring the acid-base and electrolyte balance in severely decompensated cats with UO.

Effect of amitraz and xylazine on some physiological variables of horses

Avaliaram-semos os efeitos das injecoes intravenosas (iv) de amitraz (0,1mg/kg) e xilazina (1mg/kg), em cavalos, sobre a atividade cardiaca, frequencia respiratoria, atividade motora intestinal, temperatura retal, sudorese e frequencia de apreensao de alimentos. O amitraz causouuma diminuicao significativa da atividade cardiaca, da frequencia respiratoria e da movimentacao intestinal, mas esses efeitos nao foram tao pronunciados quanto os causados pela xilazina. O amitraz causou, tambem, um relaxamento significativo da musculatura lisa retal, e um aparente aumento da sudorese e da frequencia de cavalos flagrados mastigando feno. A temperatura retal nao foi influenciada pelo amitraz. Os resultados indicam que o amitraz, na dose utilizada, nao causou efeitos colaterais severos em cavalos.

Total intravenous anesthesia with propofol and S(+)‐ketamine in rabbits

OBJECTIVE To evaluate total intravenous anesthesia with propofol alone or in combination with S(+)-ketamine in rabbits undergoing surgery. STUDY DESIGN Prospective, randomized, blinded trial. ANIMALS Nine 6-month-old New Zealand white rabbits, weighing 2.5-3 kg. METHODS Animals received acepromazine (0.1 mg kg(-1)) and buprenorphine (20 microg kg(-1)) IM, and anesthesia was induced with propofol (2 mg kg(-1)) and S(+)-ketamine (1 mg kg(-1)) IV. Rabbits received two of three treatments: propofol (0.8 mg kg(-1) minute(-1)) (control treatment, P), propofol (0.8 mg kg(-1) minute(-1)) + S(+)-ketamine (100 microg kg(-1) minute(-1)) (PK100) or propofol (0.8 mg kg(-1) minute(-1)) + S(+)-ketamine (200 microg kg(-1) minute(-1)) (PK200). All animals received 100% O(2) during anesthesia. Heart rate, mean arterial pressure, hemoglobin oxygen saturation and respiratory rate were measured every 5 minutes for 60 minutes. Blood-gas parameters were measured at zero time and 60 minutes. Additional propofol injections, if necessary, and recovery time were recorded. RESULTS An increase in heart rate was observed in P and PK200 up to 10 minutes after induction of anesthesia. Blood pressure decreased from baseline values during the first 10 minutes in P and PK200, and during the first 15 minutes and between 45 and 55 minutes in PK100. A reduction in respiratory rate was observed after 5 minutes in all treatments. Respiratory acidosis was observed in all treatments. Six (2.8) [median (interquartile range)] further propofol injections were necessary in P, which differed statistically from PK100 [1 (0.2)] and PK200 [2 (0.6)]. Recovery time was shorter in P compared with PK100 and PK200, being [7.5 minutes (4.11)], [17.5 minutes (10.30)], and [12 minutes (10.30)], respectively. CONCLUSIONS AND CLINICAL RELEVANCE S(+)-ketamine potentiates propofol-induced anesthesia in rabbits, providing better maintenance of heart rate. All of these techniques were accompanied by clinically significant respiratory depression.

Transplante autólogo de células mononucleares da medula óssea em úlcera de córnea experimental em cães

Bone marrow (BM) mononuclear cells (MC) are a great subject in tissual regeneration. The main stem cell source to the eye is the limbus. Theses cells replace injured corneal cells, however, if the limbal stem cells are not functional, a limbal deficiency with concomitant conjunctivalization takes place. This pathological condition can be caused for several reasons, in which alkali burns are the most common. To conduct a research about transplanted BM MC presence, the cells homing and to histopathologically compare the treated and sham group, an experimental corneal ulcer model associated with MC autotransplant was used. Sixteen, male or female, stray dogs suffered experimental corneal ulceration with sodium hydroxide soaked filter discs. After the lesions, animals were submitted to subconjunctival autotransplant of previously marked BM MC. The evaluation was made by immunofluorescence on the sixth day after lesions creation and histopathology was conducted 15 days after the same procedure, when it was possible to observe that the MC grafted in the injured area, the cells did not execute the homing process and, despite the inflammatory decrease, they did not help the corneal epithelial healing process in a short term evaluation. Thus, future studies about MC transplantations in corneal ulcers are indicated.

Multirresistência antimicrobiana em cepas de Escherichia coli isoladas de cadelas com piometra

The antimicrobial sensibility of Escherichia coli strains isolated from the uterine content of bitches was evaluated. Fifteen E. coli strains were tested in relation to their susceptibility to different antimicrobials. The results demonstrated 100% of resistance to all tested drugs, being a quite conflicting finding compared to other works, which observed variable resistance of those bacteria to different antimicrobials but not the same multi-resistance pattern. The detection of those multi-resistance strains configures a problem, with important implications on the antimicrobial therapy. Therefore, additional investigations for a best characterization and extension of this problem are needed.

Correlação entre as escalas visual analógica, de Melbourne e filamentos de Von Frey na avaliação da dor pós-operatória em cadelas submetidas à ovariossalpingohisterectomia

Pain evaluation in animals requires the use of evaluation scales, which depend on the interpretation made by observers. The present study aimed to evaluate the correlation between visual analog scale (VAS), Melbourne pain scale and Von Frey filaments in the evaluation of post-operatory pain in fourty two healthy adult bitches submited to ovariohysterectomy. Post-operatory pain was evaluated by two observers unaware of the analgesic protocol used, in one-hour intervals, using VAS, Melbourne pain scale and Von Frey filaments, applied around the surgical wound. A score of 50mm in VAS or 13 points in the Melbourne pain scale were considered as the criterion for analgesic administration. VAS and Melbourne pain scale showed a good correlation, with r=0.74. Correlation between VAS and Von Frey filaments was weak (r=-0.18). Correlation between Melbourne pain scale and Von Frey filaments was -0.37. VAS revealed to be the most sensitive scale. VAS and Melbourne pain scale showed a good correlation degree. It was concluded that a lower score in the Melbourne pain scale can be considered as criterion for analgesic administration.

Influência da temperatura corporal de cascavéis (Crotalus durissus) submetidas à anestesia com cetamina

The aim of the study was to verify the influence of the body temperature under physiological values and latency and recovery times on rattlesnakes anesthetized with ketamine. The animals were previously submitted to hypothermia (HYPO) (<22°C) and normothermia (30°C) (NORMO) and then, anesthetized with 80 mg/kg IM of ketamine. Latency and recovery times were evaluated by head tonus, muscular tonus and righting reflex. Heart rate (HR), time of apnea and body temperature were measured before and 5, 10, 15, 30, 60, 90 and 120 minutes after ketamine administration. Blood gases parameters were measured before, 30 and 60 minutes. It was not observed difference on latency time in both groups. The recovery time was higher on HYPO (5,5 hours) compared to NORMO (3,5 hours). HR was higher on NORMO compared to HYPO. Time of apnea was the same pattern on both groups. Compared to basal levels, time of apnea was shorter between 5 to 30 min on both groups. Respiratory acidosis was observed only at 0 min in NORMO. SvO2 was higher after 30 min, the same as with PvO2 in both groups. PvCO2 reduced after 30 min in both groups. It was evident that body temperature exerts intense influence on the recovery time on rattlesnakes anesthetized with ketamine.

Gastrointestinal parasites of owls (Strigiformes) kept in captivity in the Southern region of Brazil

The aim of this research was to study the gastrointestinal parasitism in 12 adult owls kept in captivity in the Southern region of Brazil. Cloacal contents of the species Rhinoptynx clamator, Tyto alba, Athene cunicularia, Megascops spp., and Bubo virginianus were evaluated. Feces and urine were collected and analyzed by the zinc sulfate centrifugal-flotation method and stained by the modified Ziehl–Neelsen technique. Eggs of Capillaria spp. and Strongylida, oocysts of Cryptosporidium spp., Eimeria spp., and Isospora spp. were observed. The birds showed no clinical signs, probably due to the mild nature of the infection.

Comparison of the quantification of caffeine in human plasma by gas chromatography and ELISA

In the present study we evaluated the precision of the ELISA method to quantify caffeine in human plasma and compared the results with those obtained by gas chromatography. A total of 58 samples were analyzed by gas chromatography using a nitrogen-phosphorus detector and routine techniques. For the ELISA test, the samples were diluted to obtain a concentration corresponding to 50% of the absorbance of the standard curve. To determine whether the proximity between the I50 of the standard curve and that of the sample would bring about a more precise result, the samples were divided into three blocks according to the criterion of difference, in modulus, of the I50 of the standard curve and of the I50 of the sample. The samples were classified into three groups. The first was composed of 20 samples with I50 up to 1.5 ng/ml, the second consisted of 21 samples with I50 ranging from 1.51 to 3 ng/ml, and the third of 17 samples with I50 ranging from 3.01 to 13 ng/ml. The determination coefficient (R2 = 0.999) showed that the data obtained by gas chromatography represented a reliable basis. The results obtained by ELISA were also reliable, with an estimated Pearson correlation coefficient of 0.82 between the two methods. This coefficient for the different groups (0.88, 0.79 and 0.49 for groups 1, 2 and 3, respectively) showed greater reliability for the test with dilutions closer to I50.