Eduardo Rolim de Oliveira

Perdas reprodutivas associadas com infecção por Toxoplasma gondii em caprinos no sul do Brasil

Toxoplasma gondii was implicated with reproductive losses in a goat herd in Rio Grande do Sul, Brazil. Gross changes were present in 2 out of 6 fetuses/offsprings submitted for diagnosis and included enlarged, pale mesenteric lymph nodes, and edematous, mottled red and tan lungs. Microscopic changes were observed in most fetuses and were especially characterized by lymphoplasmacytic infiltration in the brain and lungs. Other histological changes included lymphoplasmacytic interstitial nephritis, necrotizing lymphadenitis and periportal lymphoplasmacytic cell infiltrates. While bacteriological and direct immunofluorescent antibody tests for Leptospira sp. were negative in samples from all cases, immunohistochemical and PCR procedures for Toxoplasma gondii reacted positively in most of them. Antibody titles against T. gondii varying from 1:512 to 1:2048 were detected in serum samples from the mother goats of these aborted (1), stillborn (3) or dead newborn (2) kids. This paper describes the clinical, pathological, serological, molecular and immunohistochemical findings of a Toxoplasma gondii-infected goat flock.

A selective reduction of α,β-unsaturated ketones

Abstract A selective hydrogenation of carbon-carbon double bond of α,β-unsaturated ketones are obtained when a mixture of limonene, α,β-unsaturated ketone and 10% Pd/C is refluxed with vigorous stirring for 15–45 min. The best results are obtained when a molar ratio limonene:α,β-unsaturated ketone of 3:1 and 4 molar % palladium/ketone are used. The stereoselectivity is similar to the results obtained when H 2 and Pd/C have been used in neutral solvent.

Relato de uma experiência: recuperação e cadastramento de resíduos dos laboratórios de graduação do Instituto de Química da Universidade Federal do Rio Grande do Sul

An experience aiming to promote a residue interchange and recovery between the teaching laboratories of the Chemistry Institute of this University is described. At the present, several residues interchange have already appeared as advantageous. To make the work easier, a software has been developed in order to keep a record of all the residues generated by the teaching laboratories. Standard labels have been developed for the residues in order to organize them. The software and the label design are described.

An improved synthesis of homochiral octalones from (−)-carvone

Abstract A novel diastereoselective route to octalones 3 and 4 has been developed. The key step involves an asymmetric Michael addition of the corresponding chiral imine, derived from R-(+)-dihydrocarvone, to methyl vinyl ketone.

InCl3/NaClO: a reagent for allylic chlorination of terminal olefins

Tricloreto de indio na presenca de hipoclorito de sodio promove a cloracao alilica de olefinas terminais em meio bifasico (diclorometano/agua) com bons rendimentos. Para estabelecer um procedimento geral, escolheu-se a carvona como composto modelo e otimizou-se a estequiometria, temperatura, e tempo de conversao para o respectivo cloreto alilico. Tratando-se b-pineno com tricloreto de indio/hipoclorito de sodio obteve-se seletivamente o cloreto perilico, um precursor importante para a obtencao de derivados de limoneno oxigenados no carbono C-7.

Reversal of neuromuscular blockade with sugammadex in a patient with spinal muscular atrophy type III (Kugelberg–Welander syndrome)

To the Editor: Spinal muscular atrophy (SMA) represents a group of neurodegenerative disorders, most commonly autosomal recessive, that are characterized by degeneration of motor neurons of the spinal cord, skeletal muscle atrophy, and generalized weakness [1]. SMA type III (Kugelberg–Welander syndrome) has an onset of symptoms after age 18 months and a protracted course with survival into adulthood [2]. A 61-year-old man (175 cm, 85 kg) with SMA type III was scheduled for elective percutaneous closure of an ostium secundum atrial septal defect (ASD). On physical examination he had a predominantly proximal tetraparesia with marked weakness and wasting of both upper and lower limbs, affecting more the proximal musculature and the lower limbs. Anesthesia was induced with intravenous propofol (120 mg) and remifentanil (0.5 lg/kg/min) and maintained with continuous infusions of propofol (3–5 mg/kg/h) and remifentanil (0.1–0.3 lg/kg/min). Neuromuscular block (NMB) was monitored with repetitive train-of-four (TOF) stimulation (TOF-Watch SX) at the ulnar nerve. After induction of anesthesia but before the administration of rocuronium, setup and calibration of neuromuscular monitoring were performed. Baseline values of TOF ratio were above 0.90. A single dose of rocuronium (40 mg), titrated in increments of 20 mg to a TOF count of 0, was administered intravenously to facilitate tracheal intubation. Intraoperative transesophageal echocardiography confirmed the ASD with left–right shunt and showed an interauricular septum aneurysm, mild dilatation of right heart chambers, mild mitral regurgitation, and normal systolic function. At the end of the 117-min procedure, sugammadex (170 mg) was administered intravenously for reversal of NMB (TOF ratio, 0.62). The time to complete reversal to a TOF ratio of 0.90 was 69 s, with no relevant cardiovascular changes. The trachea was extubated, and the patient was transferred to the recovery ward with the same preoperative pattern of muscle weakness. No signs of residual NMB or recurarization were observed during the postoperative period. In patients with SMA there may be an increased sensitivity to nondepolarizing neuromuscular blocking agents, and suxamethonium may precipitate severe hyperkalemia [1, 2]. Our patient revealed an increased sensitivity to rocuronium as demonstrated by the presence of residual paralysis almost 2 h after a single intubating dose (approximately 20% lower than the usual standard dose of 0.6 mg/kg). Anticholinesterase agents often do not guarantee an adequate recovery of neuromuscular function, including in cases of SMA [2, 3]. In addition, they may potentiate an existing NMB when administered during late recovery, H. Vilela (&) J. Santos Department of Anesthesia, University Hospital of Santa Maria, Avenida Professor Egas Moniz, 1649-035 Lisbon, Portugal e-mail: hptvilela@gmail.com

Diastereosseletividade na redução de enonas bicíclicas com hidretos volumosos

Reduction of five substituted octalones employing lithium tri-sec-butylborohydride (L-selectride®) in THF and ethyl ether led to allylic alcohols with moderate diastereoselectivity. The stereoselectivity of addition of bulky hydrides showed to be different from most examples in the literature and was strongly influenced by substitution on the octalone ring.

Substituent influence on the diastereoselectivity of the alkylation of cyclic chiral imines

A alta diastereosseletividade, normalmente observada na reacao de alquilacao de iminas quirais derivadas de cetonas ciclicas, nao e observada no caso de cetonas com substituintes quirais. A influencia do tamanho do substituinte foi estudada com iminas preparadas a partir da (5R)-2,5-dimetilciclohexanona e (5R)-carvomentona com ambos enantiomeros da 1-feniletilamina (PEA). Usando metil vinil cetona como eletrofilo, um caso matched foi observado com a imina derivada da (S)-PEA. Entretanto, o ed depende fortemente do substituinte no caso mismatched partindo-se da (R)-PEA. O aumento do volume do substituinte leva a diminuicao do ed na ordem i Pr– < CH 2 =C(CH 3 )– < Me–. Os resultados sao explicados pela hipotese de um controle estereoeletronico a favor de um ataque axial ao tautomero enamina. O equilibrio conformacional da enamina aparenta ser crucial para explicar os dados experimentais. No caso matched somente um conformero e esperado enquanto a mistura dos conformeros e postulada no caso mismatched. The normal very high diastereoselectivity of alkylation reaction of chiral imines derived from cyclic ketones is not observed in the case of substituted chiral ketones. The influence of the substituent size was studied for imines prepared from (5R)-2,5-dimethylcyclohexanone and (5R)-carvomenthone with both enantiomers of 1-phenylethylamine (PEA). Using methyl vinyl ketone as electrophile a matched situation was observed with (S)-PEA imine derivative. However, the de is strongly dependent of the substituent in the mismatched case, starting from (R)-PEA. Enlargement of substituent size leads to lowering de in the order i Pr– < CH 2 =C(CH 3 )– < Me–. The results are reasoned by the assumption of a stereoelectronic control in favour of an axial attack at enamine tautomer. The conformational equilibrium of enamine seems to be crucial to explain experimental data. In matched case only one conformer is expected while a mixture of conformers is postulated in the mismatched one.

Aspectos regio- e estereoquímicos da adição de Michael assimétrica via iminas quirais com centros estereogênicos pré-existentes

The asymmetric Michael addition reactions using chiral imines, under neutral conditions (deracemizing alkylation process), constitute one of the main methods for the stereocontrolled elaboration of quaternary carbon centers. This protocol is based on the conjugate addition of secondary chiral enamines to electron-deficient alkenes. The focus of this report deals with the discussion of regio- and stereochemical aspects of the deracemizing alkylation process concerning enamines bearing a resident chiral center.