Influence of superovulatory protocols on in vitro production of Nellore (Bos indicus) embryos.

There are indications in the literature that delaying the period between ovarian superestimulation and ovum pick up (OPU) would induce follicles to a condition of initial atresia, which could be beneficial to oocyte development. In this work, we compared three protocols for OPU and in vitro production (IVP) of embryos, in Nellore cattle. Nellore cows (n = 18) were randomly allocated in three groups: Group 1 (OPU), Group 2 [Follicle stimulating hormone (FSH) and OPU] and Group 3 (FSH deprivation and OPU). Three OPUs were performed, and the animals were switched to a different group each time (crossover), in such a way that at the end of the experiment all cows received the 3 protocols. At random stage of the oestrous cycle (D-2), all follicles ≥ 6 mm were aspirated to induce a new follicular wave 2 days afterwards (D0). In Group 1, OPU was performed on D2 and oocytes were processed to IVP. In Group 2, starting on D0, cows were superstimulated (FSH, Folltropin(®), 30 mg administered daily, i.m., during three consecutive days, total dose = 180 mg), and 6 h after the last FSH dose, they received exogenous luteinizing hormone (LH) (12.5 mg, i.m., Lutropin(®), D3). The OPU was performed 6 h after LH administration, i.e. 12 h after the last dose of FSH. Animals in Group 3 received the same treatment as those in Group 2, except that LH was administered 42 h after the last dose of FSH, and OPU occurred 6 h later. Therefore, in this group, follicles were deprived of FSH at 48 h. Both cleavage and blastocyst rates were similar (p > 0.05, anova) among oocytes from Groups 1, 2 and 3, respectively: 77.4% (144/185) and 42.70% (79/185); 75.54% (105/139) and 31.65% (44/139); 63.52% (101/159) and 33.33% (53/159). However, hatched blastocyst rate was higher (p < 0.01) in Group 1 (30.27%, 56/185) when compared with Group 2 (11.51%, 16/139) or 3 (15.72%, 25/159). It is concluded that, contrary to previous work on European breeds (Bos taurus), ovarian superstimulation associated with deprivation of FSH and OPU (Group 3) did not increase IVP of Nellore embryos (Bos indicus). On the contrary, the highest hatched blastocyst rates were observed in oocytes from non-superstimulated cows.

Chemometric analysis of the multidrug resistance in strains of Penicillium digitatum.

Multidrug resistance activities pECr50 of diverse strains of pathogenic fungus Penicillium digitatum against seven toxicants were studied by Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). Fungal growth data (radii, circumferences, surface areas of fungal colonies, radius differences and ratios) in absence and presence of toxicants were used to derive eight new descriptors for 35 fungal strains. This data set was studied by PCA and HCA, and was correlated with the genome descriptor PCR for expression of gene CYP51 by Partial Least Squares (PLS) regression. Both analyses of pECr50 data and of fungal growth data have identified baseline resistance character, origin and target fruits of the fungal strains. In addition, the analysis of fungal growth data shows that fungal growth morphology is multivariate by nature, meaning that experimental data can be explored more intensely than in usual practice. Fungal growth is directly related to the production of enzyme P45014DM as the main resistance mechanism of P. digitatum against demethylation inhibitors. This is visible from a parsimonious PLS model (two principal components, Q2 = 0.985, R2 = 0.991, SEV = 0.028), validated with eight strains in the external validation set (Q2ev = 0.982, R2ev = 0.990, SECev = 0.025). Chemometric methods in exploring bioassay data are promising approaches to obtain useful information on fungal resistance and to apply these findings in practice.

Intrinsic bioactivity of thyrotropin in human serum is inversely correlated with thyroid hormone concentrations. Application of a new bioassay using the FRTL-5 rat thyroid cell strain.

We have developed a new bioassay for thyrotropin (TSH) in human serum to evaluate bioactivity in normal individuals and patients with different degrees of primary hypothyroidism. Unpurified TSH in serum showed no stimulation of cyclic AMP production in cultured FRTL-5 rat thyroid cells, but after immunopurification showed potent stimulatory activity. Immunoaffinity purification permitted up to 400-fold concentration of serum TSH, allowing bioactivity measurements even in certain normal sera. The limit of detection in the FRTL-5 bioassay was 10 microU of human TSH per 0.5 ml incubate, and half-maximal responses for standard human TSH was 102 +/- 26 (+/- SE) microU/0.5 ml. Immunoaffinity-purified serum TSH varied in bioactivity-to-immunoactivity (B/I) ratios from less than 0.25 to 1.21 among four euthyroid subjects and eight primary hypothyroid patients. An inverse correlation was found between B/I ratios of immunopurified basal TSH and the serum-free T4 (r = -0.7237, P less than 0.01), T4 (r = -0.6650, P less than 0.05), and T3 (r = -0.6382, P less than 0.05). B/I ratios of immunopurified TSH from three hypothyroid patients before and after acute stimulation by thyrotropin-releasing hormone showed no significant change, despite major changes in serum TSH. In summary, the present study shows an inverse relationship between the metabolic status of an individual and the intrinsic bioactivity of TSH.

Two-dimensional quantitative structure-activity relationship study of 1,4-naphthoquinone derivatives tested against HL-60 human promyelocytic leukaemia cells.

A series of 50 derivatives of 1,4-naphthoquinone tested against human HL-60 leukaemic cells showed activity at a wide range of concentrations. A multivariate quantitative structure-activity relationship (QSAR) study of 45 compounds was performed through principal component analysis (PCA) and partial least squares (PLS) regression. A good PLS regression model was obtained with two factors describing 60.1% of the total variance, and the selected descriptors were partial atomic charge at carbons 1 and 10 (C1 and C10) and total dipole moment (DIP). The calibration model exhibited the determination coefficient r2 = 0.78 and the standard error of calibration = 0.29. For external validation, r2 and the standard error of prediction were 0.74 and 0.32, respectively. DIP and C1 were the main descriptors for PCA, as well as for PLS, such that the pIC50 value increases when C1 increases and DIP diminishes. The selected descriptors are in accordance with the literature, once C10 and C1 are bound or close to the quinone oxygens involved in the production of radical anions (O2-∙). From the QSAR analysis, the structures of two new naphthoquinones were proposed and their estimated IC50 values were 1.42 and 1.13 µmol L-1.

The impact of preoperative evaluation on perioperative events in patients undergoing cataract surgery: a cohort study.

PurposeAmbulatory surgery is a major area of surgical and anesthetic practice, and preoperative clinics are being increasingly used for low-risk surgical procedures. This study investigated the impact of preoperative evaluation on perioperative events in patients undergoing cataract surgery.MethodsThis was a retrospective cohort study of 968 consecutive patients undergoing cataract surgery. Details of medical conditions, surgical, anesthetic, and postoperative information were collected from medical records. A logistic regression model was developed using propensity score adjustment for baseline characteristics.ResultsOut 968 patients included, 240 (24.7%) underwent outpatient preoperative evaluation. There were no perioperative major cardiovascular events. Hypertension occurred in 319 (33%) patients, accounting for 79.7% of all adverse events. Preoperative evaluation resulted in a lower hypertension rate after adjustment for propensity score (OR=0.6; 95% CI 0.41-0.93); no effects were observed on posterior capsule rupture and emergency visits/hospitalization within 7 days of surgery. Eighty-nine patients (9.3%) had an initial systolic pressure ≥180 mm Hg, which was not associated with higher risk of posterior capsule rupture (P=0.158) or postoperative adverse events (P=0.902). Median waiting time to surgery was 6 and 2 months for evaluated and non-evaluated patients, respectively (P<0.001).ConclusionsIn the context of low-risk surgery and no major perioperative and postoperative outcomes, it appears that outpatient preoperative evaluation has no role in reducing adverse events in cataract surgery candidates. Despite fewer hypertensive episodes observed in evaluated patients, these episodes were not associated with any medical or surgical outcomes.

Analysis of the lignocellulosic components of biomass residues for biorefinery opportunities.

The present study aims to identify the renewable resources available in Brazil such as açai seed, coconut husks, coffee husks, rice husks, eucalyptus sawdust, grass, soy peel, bamboo, banana stems and banana stalks. To identify such renewable energy sources, samples were examined for their physical and chemical characteristics using X-ray diffraction (XRD), proximate and ultimate analyses, thermogravimetric analysis (TGA), calorific value determination, near-infrared (NIR) spectroscopy, UV spectroscopy, high-pH anion-exchange chromatography (HPAEC-PAD) and accelerated solvent extraction (ASE). Among the biomasses, açai and coffee exhibited higher total sugar content, 67.70% and 62.55%, respectively. Sawdust exhibited low ash, along with the highest calorific value and lignin content. The highest glucose contents were observed in bamboo (44.65%) and sawdust (38.80%). The maximum yield for the bioproducts levulinic acid (LA), formic acid (FA) and furfural were estimated; açai exhibited the highest yield of LA and FA, while coffee exhibited the best furfural yield. All of these properties indicate that the residues are potential candidates for bioenergy production.

Multivariate analysis of coconut residues by near infrared spectroscopy.

Near infrared (NIR) spectroscopy was used to determine the content of Klason lignin, acid-soluble lignin, total lignin, extractives, ash, acid-insoluble residue, glucose, xylose, rhamnose, galactose, arabinose, mannose and total sugars in coconut residues. The samples were analyzed at several processing stages: wet unground (WU), dried unground (DU) and dried and sieved (DS). Partial least squares models were built, and the models for the analytes exhibited R(2)>0.80, with the exceptions of rhamnose, arabinose, galactose, mannose and ash from all fractions, and the lignin content from the WU fraction, which were predicted poorly (R(2)<0.70). There were some significant differences between the models for the main lignocellulosic components at the various stages of biomass. These results proved that NIR spectroscopy is useful for analysis at biorefineries, and it can be used as a faster and more economical alternative to the standard methods.

Regulation of thyrotropin (TSH) bioactivity by TSH-releasing hormone and thyroid hormone.

The regulation of TSH biological activity by thyroid hormone and TRH was studied by comparison of pituitary and in vitro secreted TSH from normal and thyroidectomized rats that were alternatively treated with TRH either in vivo or in vitro. Normal and thyroidectomized (3 weeks postthyroidectomy), rats were injected with saline or TRH (100 micrograms) three times over 24 h. Pituitaries were incubated in vitro for 6 h, and six groups of samples from both pituitary and secreted TSH were analyzed: normal (n = 6), thyroidectomized (n = 6), normal and thyroidectomized groups treated with TRH in vitro (n = 2 each) with 10(-8) M TRH added to the incubation medium, and normal and thyroidectomized groups TRH treated in vivo, their incubation medium also supplemented with 10(-8) M TRH (n = 4 each). The biological activity of TSH in pituitary extracts and media was analyzed in terms of the ability to stimulate adenylate cyclase in human thyroid membranes. Thyroidectomy significantly decreased pituitary TSH bioactivity (70%) compared to normal, with no effect on secreted TSH in the medium. TRH, both in vivo and in vitro, when compared to the corresponding untreated groups, produced a significant increase in bioactive TSH in media from both normal (TRH in vivo, 131%; TRH in vitro, 139%) and thyroidectomized samples after TRH in vivo (158%). The TRH effect in the pituitary showed a significant increase in TSH bioactivity from normal samples treated with TRH in vivo (137%), whereas in thyroidectomized pituitary samples with TRH in vitro, TSH bioactivity was decreased (69%). These results indicate that thyroid hormone deficiency and TRH differentially regulate TSH bioactivity. Thyroid hormone deficiency induced a decrease in pituitary TSH bioactivity and favored the effect of TRH on secretion of more bioactive forms. TRH not only induced the formation of more bioactive forms but also stimulated their secretion into the medium.

Decreased nuclear uptake of [125I]triiodo-L-thyronine in fibroblasts from patients with peripheral thyroid hormone resistance.

The cellular mechanisms that cause the syndrome of generalized, peripheral, and pituitary resistance to thyroid hormones are unclear. In order to investigate the possibility of a defect at the nuclear receptor for T3, we examined: 1) equilibrium binding of [125I]T3 (64 analyses) to the nuclei of intact cultured fibroblasts from 12 patients with both sporadic and familial generalized or selective pituitary resistance, 17 normal subjects, and two apparently normal siblings from affected families; and 2) kinetics of [125I]T3 nuclear uptake (22 analyses) in intact fibroblasts from 4 generalized resistant patients from two different kindreds, compared to one apparently normal sister of one affected patient and 6 normal subjects. Statistical analysis of the equilibrium binding parameters showed no differences in nuclear binding capacity for T3 among all groups. The equilibrium dissociation constants (Kd) also were not significantly different in fibroblasts from the selective pituitary resistant patients, the normal siblings, and the normal subjects. In contrast, the KdS from the general resistant patients were significantly increased (median = 1.94 X 10(-10) M, 5-95% confidence interval = 1.18-2.93 X 10(-10) M 1.11, 0.77-1.25 X 10(-10) M; P less than 0.008). Since there was considerable overlap of the equilibrium binding values among groups, we studied the kinetics of [125I]T3 nuclear uptake in selected cell lines from normal subjects and familial generalized resistant patients. Kinetic analysis of the association curve revealed that, compared to the normal subjects, maximum binding at 10(-10) M [125I]T3 was significantly reduced to 50% in two resistant patients, to 10% in another two patients, and to 65% in one apparently-normal sibling. The empiric parameter lambda that corresponds to the slope at the origin of the curve was not significantly different in any patient compared to normal. The calculated apparent association constant, derived from lambda, and the binding capacity obtained at equilibrium, showed differences that were significant for only one of the patients. We conclude that cultured fibroblasts from patients with familial generalized resistance to thyroid hormone display abnormal kinetics of T3 nuclear uptake which provide a convenient in vitro method for the recognition of thyroid hormone resistance at the cell level. Furthermore, because cultured fibroblasts can be grown under controlled experimental conditions, they are a suitable tissue for further study of the molecular basis of these disorders.

Weak acid inhibition of fermentation by Zygosaccharomyces bailii and Saccharomyces cerevisiae.

The inhibition kinetics of fermentation by Zygosaccharomyces bailii and Saccharomyces cerevisiae were evaluated for weak carboxylic acids. Several regression equations were tried to fit the experimental data, most cases being best fitted to exponential curves. The following parameters were determined: i) acid concentration responsible for 50% inhibition of fermentation (C50%); ii) area under the regression curve up to that concentration (A50%) and iii) exponential inhibition constant (k(i)). These parameters were compared according to their ability to express the inhibitory effect of each acid. In broad terms, the values of k(i) in association with minimum inhibitory concentrations (x(min)), were found best to express the inhibitory effect of the weak acids. However, C50% values were satisfactorily correlated with k(i). The value of A50% more precisely reflected the occasional stimulatory effect of low concentrations of weak acids. Comparison of inhibition parameters for Z. bailii and for S. cerevisiae revealed a higher resistance of the former to acetic, propionic, butyric and benzoic acids and similar resistance to caproic, caprylic and sorbic acids. Previous cultivation in the presence of acetic, propionic and benzoic acids showed a distinct influence on the resistance of both yeasts, although it did not always induce cellular adaptation. Fermentation inhibition showed a good correlation with the lipid solubility of weak acids suggesting that the acids interact with the hydrophobic regions of cell membranes.

When and how to report results of surgery on atrial fibrillation.

OBJECTIVE: Several medical, interventional and surgical techniques are used to treat atrial fibrillation, aimed at different goals and having variable success rates. To be able to assess and compare all these techniques a methodology of study and a classification is proposed. METHODS: We developed a five grade score, named the Santa Crus Score, based upon the post-operative atrial rhythm and the effective atrial contraction. Score 0 corresponds to a persistence of atrial fibrillation, the presence of a regular rhythm is grade 1, 2 or 3 if there is no atrial contraction; right atrial contraction; or bilateral atrial contraction, respectively. Score 4 corresponds to sinus rhythm and bilateral atrial contraction. Surgery for atrial fibrillation was performed on 51 patients since 1992. All patients but two had associated mitrial surgery. Three different maze techniques were performed on 17 patients and the pulmonary veins isolation procedure on 34 patients. Patients were reassessed at 1, 6, 12, 24 and 36 months. RESULTS: After the maze I procedure atrial fibrillation eradication was achieved in 88% of patients but none scored 4. Three patients changed score during the first year. All maze III patients scored 0 initially and one changed to score 3 in the first year. Sixty percent of the maze IIIA patients scored 4, but one evolved to score 0 at 6 months. The pulmonary veins isolation technique eliminated atrial fibrillation in 71% of the patients initially, and in 60% after 1 year, and achieved a score of 4 in a third of the patients. CONCLUSION: This classification considers the intermediate grades of success that can occur with absence of atrial fibrillation and is applicable to all forms of therapy.

Surgery for atrial fibrillation using radiofrequency catheter ablation: assessment of results at one year.

OBJECTIVE: The results obtained in 43 patients using direct intraoperative radiofrequency catheter ablation, as an alternative to surgical incisions, to perform atrial fibrillation surgery, are presented. METHODS: Forty-three patients with ages ranging from 43 to 74 years (x = 59), with chronic atrial fibrillation with an average duration 6+/-5 years were operated. Eleven patients suffered from clinically relevant tachyarrythmia and eight had previous thromboembolic events. All but one patient had concomitant mitral valve surgery. Direct intraoperative radiofrequency catheter ablation was used to perform endocardial bilateral isolation of the pulmonary veins from the left atrium. RESULTS: There were no local or general complications, namely bleeding or thromboembolic events. Of the 33 patients with more than 3 months of follow-up, 36% remained in atrial fibrillation (Santa Cruz score 0); 30% had Score 4; 18% had Score 3; 6% had Score 2; 9% had Score 1. CONCLUSIONS: We conclude that the use of intraoperative radiofrequency catheter ablation is fast and safe. Presently, this is our method of choice for surgical treatment of atrial fibrillation in mitral patients.

Polycyclic aromatic hydrocarbons: a QSPR study. Quantitative structure-property relationships.

This work deals with 48 substances composed exclusively of unsubstituted six-membered fused aromatic rings. In the first step, physicochemical properties which are relevant in environmental studies such as the boiling temperature (Tb), the retention index (RI), n-octanol/water partition coefficient (KOW) and solubility (S) are related with a series of electronic, geometric and topological descriptors. Among them are: electron affinity, the difference between electron affinity and ionization potential (GAP), Wiener, and connectivity indexes, volume, surface area, length-to-breadth ratio and enthalpy of formation. In a second step, these properties were incorporated into the descriptor matrix to build several quantitative structure-property relationships and to obtain prediction rules for the log KOC, log KOA, bioconcentration factor (BCF) and Henry's law constant (H). Finally, the photo-induced toxicity of freshwater organism Daphinia-Magna is modeled using the following transformed electronic descriptors: electron affinity, ionization potential and Gap.

Renal adenocarcinoma presenting with bilateral metastases to Bartholin's glands: primary diagnosis by aspiration cytology.

The first recorded case of renal adenocarcinoma presenting with bilateral metastases to the Bartholin's glands is presented. Primary diagnosis of the metastatic deposits was made by fine-needle aspiration cytology with subsequent localization of the unsuspected renal primary. The value of fine-needle aspiration in the identification of inapparent primary tumors is discussed and cytological findings are described in detail.

Endometriosis of the rectovaginal septum. Diagnosis by fine needle aspiration cytology.

The cytologic picture seen in two cases of rectovaginal endometriosis diagnosed by fine needle aspiration (FNA) cytology is presented in detail. The cell pattern differed considerably from that previously described in fluid specimens and more closely resembled the exfoliation observed in direct endometrial samples. No previous report appears to exist on the diagnosis of rectovaginal endometriosis by FNA.

Evaluation of phenolic compounds in Brazilian propolis from different geographic regions.

Chemometrics has been shown quite efficient to uncover relationships between chemical composition of a sample and its geographical origin. Forty propolis samples originated from the the South and South East of Brazil were analyzed by HPLC and 18 compounds of interest were studied which included: caffeic, p-coumaric and ferulic acids, and some of their derivatives, pinobanksin, a derivative of kaempferol and five phenolic compounds (assigned as 3-prenyl4-hydroxycinnamic acid (PHCA); 2,2-dimethyl-6-carboxyethnyl-2H-1-benzopyran (DCBE); 3,5-diprenyl-4-hydroxycinnamic acid (DHCA); compound E (still unknown) and 6-propenoic-2,2-dimethyl-8-prenyl-2H-1-benzopyran acid (DPB). Principal Component Analysis (PCA) indicated three different groups of propolis samples, having the same typical chromatogram, evaluated by HPLC. Samples from the South East group were rich in derivatives of kaempferol. Samples from the South group I had a high content of DPB compound, but a low concentration of kaempferol derivatives and of DCBEN compound. Samples from the South group II were characterized by a high concentration of DCBEN, DHCA, p-coumaric and DPB compounds. Therefore, the identification of new compounds in Brazilian propolis can give, useful information about the plant sources of a given geographic region.

[Mechanism of action of thyroid hormones at the cellular level]. / Mécanismes d'action des hormones thyroïdiennes au niveau cellulaire.

Thyroid hormones exert pleiotropic effects at the cell level and several theories to define the initial site of action have been proposed. First mitochondria, nuclei or plasma membrane were considered as the main regulatory step. More recently, evidence of T3 and/or T4 binding sites present in different cellular compartments suggests the existence of more than one initial site of action. Binding sites from cytosol or plasma membrane and endoplasmic reticulum seem to participate either in the storage of thyroid hormones, or in their intracellular transport and metabolism. Mitochondrial and certain plasma membrane binding sites could be responsible for rapid effects of thyroid hormones at their level. Nuclear T3 binding sites located in the chromatin are considered as a true hormone receptor and are more documented in a structural and functional point of view. They may mediate thyroid hormone effects on the regulation of DNA transcription and the synthesis of active proteins. Their mechanism of action is nevertheless not well defined.

[Primary mesothelioma of the pericardium: a clinical case]. / Mesotelioma primário do pericárdio: um caso clínico.

We describe a 33-years-old male patient, presenting with progressive right heart failure. After evaluation, the hypothesis of effusive-constrictive pericarditis was considered. Medical therapy was initiated with no clinical benefit. On the 15th day after admission he was proposed for surgical intervention. The intraoperatory examination revealed a thick pericardium adhering to the epicardium without a clear separation between them. Complete resection was technically impossible. The postoperative course evolved with worsening heart failure and development of renal failure requiring hemodialysis. A diagnosis of primary pericardial mesothelioma was made after histological evaluation. The patient died 8 days after surgery despite all efforts at hemodynamic compensation. Despite its rarity, this diagnosis should be considered in cases with rapid evolution of constrictive or effusive-constrictive pericarditis. The prognosis for pericardial mesothelioma is poor due to its late diagnosis, the difficulty of surgical excision and poor response to radio- or chemotherapy.

[Surgery of atrial fibrillation with intraoperative radiofrequency]. / Cirurgia da fibrilhação auricular utilizando radiofrequência intra-operatório.

Radiofrequency ablation is successful in most supraventricular tachyarrhythmias and the first results in percutaneous applications in atrial fibrillation have been published. At present, all the surgical techniques for the treatment of atrial fibrillation use extensive atrial incisions. A case report is presented of a 67 year old woman with chronic atrial fibrillation and rheumatic mitral and tricuspid valve disease. At surgery, pulmonary vein isolation was performed using a continuous linear ablation around the pulmonary veins, instead of using extensive atrial incisions. Concomitantly, a mitral valve replacement and tricuspid valve annuloplasty were performed. Five months after surgery the patient remains with a stable sinus rhythm surgery and in functional class I (NYHA).

[Atrial fibrillation surgery using intraoperative radiofrequency]. / Cirurgia da fibrilhação auricular utilizando radiofrequência intra-operatória.

Radiofrequency ablation is successful in most supraventricular tachyarrhythmias and the first results in percutaneous applications in atrial fibrillation have been published. At present, all the surgical techniques for the treatment of atrial fibrillation use extensive atrial incisions. A case report is presented of a 67 year old woman with chronic atrial fibrillation and rheumatic mitral and tricuspid valve disease. At surgery, pulmonary vein isolation was performed using a continuous linear ablation around the pulmonary veins, instead of using extensive atrial incisions. Concommitantly, a mitral valve replacement and tricuspid valve annuloplasty were performed. Five months after surgery, the patient remains with a stable sinus rhythm surgery and in functional class I (NYHA).