Vertical distribution and aggregation patterns of krill (Crustacea: Euphausiacea) in the Bay of Biscay: interannual and seasonal variability

Studies of krill (Crustacea: Euphausiacea) in oceanic waters of the Bay of Biscay are scarce and restricted to the epipelagic zone, overlooking vertical dynamics such as diurnal vertical migration (DVM). There is a growing interest in acoustically evaluating the biomass of krill in this area, but this requires a good knowledge of its vertical dynamics and aggregation patterns. In this work we employed acoustic data and net samples from two consecutive annual surveys covering a wide off-shelf area of the Bay of Biscay (JUVENA surveys of 2013 and 2014) and four seasonal surveys covering slope and oceanic waters in the Cantabrian Sea (SCAPA surveys of 2015). Vertical dynamics of krill were analyzed in the frame of the environmental seascape. High interannual and seasonal variations in the vertical distribution and aggregation patterns (small swarms, dense aggregations, or loose layers) of krill were observed. The vertical distribution covaried with dissolved oxygen and salinity. According to our findings, the best season to acoustically evaluate krill in the Bay of Biscay is spring, with the bulk of the biomass located above 600 m depth. Moreover, extending the acoustic recording beyond the epipelagic zone is mandatory for any season.

Refractory Anemia in a Kidney Transplant Recipient

Anemia is a common finding after kidney transplantation (KT). Herein, we present a 34-year-old man who received a deceased-donor KT in 2017. Induction immunosuppression therapy consisted of thymoglobulin, tacrolimus (TAC) and methylprednisolone; the maintenance therapy included mycophenolate (MMF) 500 + 500 mg, TAC 4 + 4 mg and prednisolone (PD) 5 mg. One year after KT, he progressively developed dyspnea and fatigue. Laboratory exams revealed hypochromic microcytic anemia unresponsive to increasing doses of darbepoetin. Upper endoscopy and colonoscopy were normal. Bone marrow examination revealed erythroid hyperplasia with numerous proerythroblasts. Serology and viral load for human parvovirus B19 were both positive. Immunosuppression was reduced; he was treated with immunoglobulin. After one week, anemia improved. After 2 months the patient remained asymptomatic with stable hemoglobin. Although rare, PVB19 infection is a clinically significant infection that often presents as aplastic anemia in the post-transplantation period.

Analyzing similarities in genome sequences

This article investigates aspects of similarity between complete sequences of mitochondrial DNA by determining the distribution of the relative frequencies of words with different lengths and the characteristics of their relevance throughout the sequences. The degree of similarity is obtained by comparing the distances between words contained within these sequences. Our results indicate that the best groupings among different species depend on the lengths of words and their respective relative frequencies. We also observed that the longer the word the more consistent the grouping between the sequences becomes. The application of our results, together with the perspective of analyzing DNA sequences belonging to a single biological species, may be important for the construction of phylogenetic trees, which are appropriate structures for understanding the evolutionary history of the species.

Comportamento alimentar de vacas Nelore e de seus bezerros puros ou mestiços

RESUMO O objetivo desta pesquisa foi avaliar a influência do grupo genético do bezerro no comportamento alimentar diurno de mães e suas crias. Foram utilizadas 24 vacas Nelores paridas e seus bezerros, oito Nelores (puros), oito 1/2 Simental 1/2 Nelore e oito 1/2 Red Angus 1/2 Nelore. Avaliaram-se as medidas de frequência e duração das mamadas, tempo de pastejo e ruminação dos bezerros e das vacas. Os bezerros puros mamaram mais frequentemente que os mestiços (3,51 vs. 3,17 vezes/dia), porém com menor duração de mamada (7,37 vs. 7,80 minutos). A frequência de mamadas, a duração de cada mamada e o tempo total de mamadas diminuíram com o aumento da idade do bezerro. Nos bezerros, pastejo e ruminação aumentaram com a idade; entretanto, nas vacas, aumentou o tempo de pastejo e diminuiu o de ruminação com o passar dos dias. Os bezerros mestiços pastaram, em média, 18 minutos a mais que os puros, e os machos 16 minutos a mais que as fêmeas. Os bezerros machos ruminaram, aos 40 dias de idade, 25 minutos a mais que as fêmeas, mas essa diferença diminuiu com a idade e desapareceu por volta dos 220 dias. O comportamento da mãe e de sua cria é influenciado pelo grupo genético desta última.

Liquid-based cytology and cell block immunocytochemistry in veterinary medicine: comparison with standard cytology for the evaluation of canine lymphoid samples

Liquid-based Cytology (LBC) consists of immediate wet cell fixation with automated slide preparation. We applied LBC, cell block (CB) and immunocytochemistry to diagnose canine lymphoma and compare results with conventional cytology. Samples from enlarged lymph nodes of 18 dogs were collected and fixed in preservative solution for automated slide preparation (LBC), CB inclusion and immunophenotyping. Two CB techniques were tested: fixed sediment method (FSM) and agar method (AM). Anti-CD79a, anti-Pax5, anti-CD3 and anti-Ki67 were used in immunocytochemistry. LBC smears showed better nuclear and nucleolar definition, without cell superposition, but presented smaller cell size and worse cytoplasmic definition. FSM showed consistent cellular groups and were employed for immunocytochemistry, while AM CBs presented sparse groups of lymphocytes, with compromised analysis. Anti-Pax-5 allowed B-cell identification, both in reactive and neoplastic lymph nodes. Our preliminary report suggests that LBC and FSM together may be promising tools to improve lymphoma diagnosis through fine-needle aspiration.

Ureia e glicerina bruta como aditivos na ensilagem de cana-de-açúcar

Objetivou-se avaliar a inclusão de ureia e glicerina bruta como aditivos na ensilagem da cana-de-açúcar, na composição químico-bromatológica, pH, N-amoniacal (N-NH3) e digestibilidade in vitro (DIV). Os tratamentos foram quatro doses de ureia, 0, 10, 20 e 30 g de ureia por kg de cana-de-açúcar na ensilagem, e cinco doses de glicerina bruta, 0, 10, 20, 30 e 40g de glicerina bruta por kg de cana-de-açúcar na ensilagem. As silagens foram armazenadas por 180 dias. O tratamento com ureia afetou a maioria das variáveis relacionadas ao valor nutritivo, aumentando os teores de matéria seca (MS) e proteína (PB) (2,58; 7,76; 18,70 e 19,31%), reduzindo os teores de fibra em detergente neutro (FDN) e melhorando a DIV da MS (42,61; 48,53; 50,69 e 51,18%) e FDN (38,81; 39,23; 41,06 e 43,46%), e as características fermentativas da silagem, apresentando valores de pH de 3,49; 3,86; 4,18 e 3,93 e de N-NH3 de 1,72; 3,80; 7,88 e 9,00, para as dose de 0, 10, 20 e 30 g, respectivamente. A glicerina bruta aumentou os teores de MS e extrato etéreo (1,45; 3,03; 3,62; 3,41 e 4,38%), melhorou a DIV da MS com valores de 49,61; 52,24; 53,28; 55,60 e 56,09% e reduziu perdas por gases durante o processo de fermentação, apresentando médias de 6,69; 5,97; 5,89; 5,51 e 5,48% da MS para as doses 0, 10, 20, 30 e 40g, respectivamente. Assim, a ureia e a glicerina bruta podem ser utilizadas como aditivos na ensilagem da cana-de-açúcar.

Fontes de amido no concentrado de bovinos superprecoces de diferentes classes sexuais

Objetivou-se avaliar duas fontes de amido (milho ou sorgo) no concentrado e três classes sexuais sobre o consumo de nutrientes, o desempenho e as características da carcaça de bovinos superprecoces. Foram utilizados 30 animais cruzados Beefalo-Nelore, com peso corporal médio inicial de 234,38±26,17kg, em delineamento inteiramente ao acaso, em esquema fatorial 2x3 (duas fontes de amido e três classes sexuais: fêmeas, machos castrados e machos não castrados). O período experimental foi de 224 dias. Na fase inicial (zero-17 semanas), os ganhos de peso total (GPT) e diário (GMD) foram 150,62 e 108,62kg e 1,27 e 0,91kg/dia, respectivamente, para milho e sorgo. Na fase final (17-32 semanas), houve efeito da fonte de amido para o peso de carcaça, com médias de 273,00 e 231,95kg, respectivamente, para os tratamentos com milho e sorgo. Houve efeito de classe sexual para GP, GMD e eficiência alimentar, com médias de GP iguais a 98,17, 124,70 e 119,70kg, GMD de 0,93, 1,19 e 1,14kg/dia e 8,66, 12,24 e 11,09%, respectivamente, para fêmeas, machos castrados e machos não castrados. Espessura de gordura subcutânea (EGS) apresentou médias de 10,50; 5,97 e 5,51mm, respectivamente, para fêmeas, machos castrados e machos não castrados. Recomenda-se o milho como fonte de amido na fase inicial do confinamento de superprecoces. Na fase final (17-32 semanas), não há distinção entre milho ou sorgo. As fêmeas apresentaram maior EGS, e os machos, castrados e não castrados, apresentaram maior eficiência alimentar na fase final do confinamento.

Improved renal function after kidney transplantation is associated with heme oxygenase-1 polymorphism

Heme oxygenase-1 (HO-1) has a microsatellite polymorphism based on the number of guanosine-thymidine nucleotide repeats (GT) repeats that regulates expression levels and could have an impact on organ survival post-injury. We correlated HO-1 polymorphism with renal graft function. The HO-1 gene was sequenced (N = 181), and the allelic repeats were divided into subclasses: short repeats (S) (<27 repeats) and long repeats (L) (>/=27 repeats). A total of 47.5% of the donors carried the S allele. The allograft function was statistically improved six months, two and three yr after transplantation in patients receiving kidneys from donors with an S allele. For the recipients carrying the S allele (50.3%), the allograft function was also better throughout the follow-up, but reached statistical significance only three yr after transplantation (p = 0.04). Considering only those patients who had chronic allograft nephropathy (CAN; 74 of 181), allograft function was also better in donors and in recipients carrying the S allele, two and three yr after transplantation (p = 0.03). Recipients of kidney transplantation from donors carrying the S allele presented better function even in the presence of CAN.

SOK1 translocates from the Golgi to the nucleus upon chemical anoxia and induces apoptotic cell death

SOK1 is a Ste20 protein kinase of the germinal center kinase (GCK) family that has been shown to be activated by oxidant stress and chemical anoxia, a cell culture model of ischemia. More recently, it has been shown to be localized to the Golgi apparatus, where it functions in a signaling pathway required for cell migration and polarization. Herein, we demonstrate that SOK1 regulates cell death after chemical anoxia, as its down-regulation by RNA interference enhances cell survival. Furthermore, expression of SOK1 elicits apoptotic cell death by activating the intrinsic pathway. We also find that a cleaved form of SOK1 translocates from the Golgi to the nucleus after chemical anoxia and that this translocation is dependent on both caspase activity and on amino acids 275-292, located immediately C-terminal to the SOK1 kinase domain. Furthermore, SOK1 entry into the nucleus is important for the cell death response since SOK1 mutants unable to enter the nucleus do not induce cell death. In summary, SOK1 is necessary to induce cell death and can induce death when overexpressed. Furthermore, SOK1 appears to play distinctly different roles in stressed versus non-stressed cells, regulating cell death in the former.

GHRH proliferative action on somatotrophs is cell-type specific and dependent on Pit-1/GHF-1 expression

To investigate the mechanisms by which the hypothalamic peptide GHRH influences cell division, we analyzed its effects on the proliferation of two different cell lines: CHO-4, an ovary-derived cell line, and GH3, a pituitary-derived cell line. We found that GHRH induces the proliferation of pituitary-derived cells but inhibits the proliferation of ovary-derived cells. We further characterized this dual effect of GHRH to find that the cytoplasmic signals induced by this hormone are similar in both cell lines. Moreover, in CHO-4 cells GHRH stimulates two well-known positive cell cycle regulators, c-myc and cyclin D1, but is unable to induce the degradation of the negative cell cycle regulator p27(Kip1). Significantly, when the Pit-1/GHF-1 gene is exogenously expressed in CHO-4 cells, the negative effect of GHRH on the proliferation of these cells is attenuated. Furthermore, when the levels of Pit-1 are downregulated by siRNA in GH3-GHRHR cells, the positive effects of GHRH on the proliferation of these cells are diminished. These findings add to our understanding of the molecules involved in the regulation of cell proliferation by GHRH, as we demonstrate for the first time that Pit-1 is not only required to drive the expression of the GHRH receptor, as previously described, but is also needed for the downstream effects that occur after its activation to modulate cell proliferation. These data suggest that the regulation of cell proliferation in response to a specific growth factor depends in certain cell populations on the presence of a tissue-specific transcription factor.

Incidence of donor and recipient toll-like receptor-4 polymorphisms in kidney transplantation

Toll-like receptors (TLR) comprise an emerging family that recognize pathogen-associated molecular patterns and promote the activation of leukocytes. Recently, TLR has been demonstrated to play a role in experimental allograft rejection. However, the TLR-4 gene has a polymorphism that can be associated with a blunted immune response, especially to microbial pathogens. We sought to study the incidence of TLR 4 gene variants among renal transplant donors and recipients from living and deceased organs and then to correlate them with short-term and long-term outcomes.

METHODS

Analysis of TLR4 polymorphisms at Asp299Gly and Thr399Ile codons were performed using restriction fragment length polymorphism. Demographic data was obtained from patient records.

RESULTS

Among 201 patients, 141 were recipients from related donors (group 1) and 60 recipients from 45 deceased donors (group 2). Patients were followed for 108 +/- 85 months after transplantation. The incidence of polymorphism for TLR-4 Asp299Gly, Thr399Ile or both were 8.9% in recipients and 8.0% in donors. Patients who received a kidney with polymorphism, Asp299Gly, or Thr399Ile, or both, did not show a difference in rate of acute tubular necrosis compared with controls (no polymorphism). Acute rejection occurred in 17.6% of recipients with Asp299Gly/Thr399Ile polymorphisms and in 39.5% of wild-type recipients (P = .400). The incidence of bacterial infection was equal in both groups.

CONCLUSION

The incidence of polymorphism in this study was similar in both groups, and donor or recipient polymorphisms were not associated with different renal graft outcomes.

The GCK II and III subfamilies of the STE20 group kinases

The Ste20 (sterile 20) proteins are a large family of serine/threonine kinases. Since their discovery a growing body of evidence has implicated them in the regulation of signaling pathways governing cell growth, cell differentiation cell death and cell volume. Approximately 30 human members have been identified based on the high degree of homology of their catalytic domain to that of the Ste20p from Saccharomyces cerevisiae. In addition to the conserved regions, there are also regions of sequence that make each of them unique. In this review we will focus on two subfamilies of the group, GCK-II and GCK-III, families that are closely related but, again, unique in their structural features and biological functions. Herein, we will present what we hope will be the current state of knowledge about these kinases, and discuss what remains to be done in order to better understand their activity and regulation.

L-Phenylalanine–4-nitrophenol (1/1)

In the 1:1 adduct formed between L-phenylalanine and 4-nitrophenol [alternative IUPAC name: (2S)-2-ammonio-3-phenylpropanoate-4-nitrophenol (1/1)], C9H11NO2.C6H5NO3, the L-phenylalanine molecule is in the zwitterionic state. The overall structure is stabilized via strong hydrogen bonding between polar zones and van der Waals interactions between non-polar zones, which alternate with the polar zones.

Supramolecular structure and second harmonic generation in strontium bis(hydrogenL-malate) hexahydrate

The title compound, tetraaquabis(hydrogen L-malato)strontium(II) dihydrate, [Sr(C4H5O5)2(H2O)4].2H2O, is a new non-linear optical semi-organic material with a second harmonic generation efficiency approximately 3.5 times greater than that of potassium dihydrogen phosphate. The malate anions are interconnected through directional O-H...O hydrogen bonding, in a head-to-tail arrangement, creating extended anionic chains along [001]. Neighbouring parallel chains are crosslinked by water molecules, resulting in a three-dimensional architecture. The Sr2+ ion is coordinated by eight O atoms. This material is a new candidate for non-linear optical applications since the crystals are stable and easy to grow.

Efeito do creep feeding sobre o desempenho de bezerros e a eficiência reprodutiva de primíparas Nelore, em pastejo

Avaliou-se o efeito da suplementação de bezerros em sistema de creep feeding, em pastagens de Brachiaria brizantha, durante o período de amamentação, sobre o ganho médio diário (GMD), peso à desmama (PD) e taxa de gestação, em delineamento inteiramente ao acaso, utilizando 102 vacas Nelore (primíparas de baixa condição corporal ao início da estação de monta) e seus bezerros, divididos em dois grupos: T1 (n=52), não tratado e T2 (n=50), tratado com suplemento à base de 20% de PB e 75% de NDT. O consumo médio diário estimado no período foi 0,61kg de suplemento/bezerro/dia. Observaram-se diferenças entre T1 e T2 quanto ao PD (P<0,01) e GMD (P<0,05), com valores, respectivamente, de 155,10±2,72 e 163,80±2,53kg; e 0,59±0,015 e 0,64±0,014kg. A taxa de gestação não foi influenciada pelos tratamentos (P>0,05). A suplementação em creep feeding pode aumentar o GMD e o PD de bezerros Nelore, sem alterar a taxa de gestação de primíparas que iniciam a estação de monta com baixa condição corporal.

Self-similarity and protein chains

Fractal properties of 5526 different protein chains are investigated. Characteristic fractal behavior for different molecular systems is obtained from the fractal dimension analysis, which shows that the dimension is delta=2.47 . This dimension gives a measure of the protein compactness. The present finding indicates that the fractal analysis describes some structural properties of proteins and corroborates the explanation about multifractality in the energy hypersurface.

Efeito de aditivos biológicos comerciais na silagem de capim-elefante (Pennisetum purpureum Schum)

Avaliaram-se o pH e a composição bromatológica de silagens de capim-elefante var. Napier, sem e com três aditivos biológicos comerciais (B, C e D) em duas concentrações de diluição, a recomendada pelo fabricante (concentração 1) ou com o dobro (concentração 2), feitas em microsilos de PVC. O delineamento experimental foi inteiramente ao acaso, com sete tratamentos e seis repetições por tratamento. Apenas o aditivo B em ambas as concentrações (3,73; 4,07) foi eficiente em reduzir (P<0,05) o pH em relação ao tratamento-controle (5,01). A porcentagem de matéria seca aumentou (P<0,05) com o uso do aditivo B, nas concentrações 1 (29,9) e 2 (31,3), e dos aditivos C e D, na concentração 2 (26,8; 25,7). Quanto à proteína bruta, somente houve diferença (P<0,05) entre o tratamento-controle (6,6) e os dois tratamentos com aditivo B (13,4; 12,09). As frações de fibra em detergente neutro e lignina foram menores (P<0,05) nos tratamentos com aditivo B em relação ao tratamento-controle. A duplicação da dose do aditivo B não aumentou sua eficiência. Nos macro-elementos cálcio e fósforo das silagens, todos os aditivos elevaram a concentração de cálcio e não alteraram a de fósforo. Concluiu-se que o aditivo B, constituído de Lactobacillus plantarum e Pediococcus acidilactici, melhorou tanto a qualidade de fermentação quanto o valor nutritivo da silagem de capim-elefante, e que a duplicação da concentração dos produtos não aumentou (P<0,05) a qualidade das silagens.

Tamanho de vacas Nelore adultas e seus efeitos no sistema de produção de gado de corte

Utilizaram-se 20 vacas adultas paridas, confinadas em piquetes-baias com cochos individualizados para vaca e para bezerro, com o objetivo de se estudar características relacionadas às medidas esqueléticas, peso e condição corporais e seus efeitos sobre o sistema de produção. Avaliou-se o tamanho das vacas com base em medidas de altura da cernelha (1,40±0,03m), altura da garupa (1,40±0,04m), perímetro torácico (1,84±0,04m), comprimento corporal (1,38±0,13m), área corporal (4,6m²) e peso corporal (442,70±29,9kg). As características relacionadas às medidas de tamanho apresentaram correlações entre si de média a alta magnitude. A área corporal se apresentou altamente correlacionada com as demais características. Em razão da variabilidade do peso corporal, sugere-se sua mensuração com outras medidas lineares relacionadas com o tamanho corporal com vistas à determinação do tamanho corporal mais adequado.

Synthesis, structure, thermal and non-linear optical properties of L-argininium hydrogen selenite

L-Argininium hydrogen selenite (C(6)H(15)N(4)O(2)HSeO(3)) is a new semiorganic compound of the hydrogen selenite family with non-linear optical properties. The crystal lattice is monoclinic with unit-cell parameters a = 22.493 (5), b = 5.1624 (13), c = 9.730 (4) A, beta = 95.68 (3) degrees, V = 1124.3 (6) A(3), Z = 4, space group C2. Second-harmonic generation measurements performed on powder samples, using a Q-switched Nd:Yag laser (lambda = 1064 nm), showed the second-harmonic power to be about twice that of urea. Differential scanning calorimetry measurements revealed the existence of a phase transition with onset at 289 K.

Multifractality, Levinthal paradox, and energy hypersurface

Multifractal properties in the potential energy hypersurface of polypeptides and proteins are investigated. Characteristic multifractal behavior for different molecular systems is obtained from the f(alpha) spectra. The analysis shows that the dimension of the phase space of the problem influences the accessibility to different parts of the potential energy hypersurface. Also, we show that it is necessary to take into account the H-bond formation between amino acids in the conformational-folding search. The present findings indicate that the f(alpha) function describes some structural properties of a protein. The behavior of the f(alpha) spectra gives an alternative explanation about the Levinthal paradox. Furthermore, the anomalous temperature dependence of the Raman spin-lattice relaxation rates can be related to the perturbations in the secondary structures.

[Genotypic resistance to antiretroviral drugs in patients with therapeutic failure to highly active antiretroviral therapy]

BACKGROUND

To assess genotypic resistance mutations in patients with virological failure with highly active antiretroviral therapy (HAART) METHODS: Genotyping of reverse transcriptase (RT) and protease (PRO) HIV-1 genes were carried out in 33 adherent patients failing on HAART.

RESULTS

Resistance mutations were found in 32 of the 33; 27 of them (81.8%) being primary mutations: 26 (78.8%) in the RT gene and 60 (60.6%) in the PRO gene. Overall, 66.6% had genotypic resistance to two drugs and 60.6% showed resistance to drugs belonging to the two main classes of antiretroviral drugs. At the time of treatment failure, 72.7% had on their therapeutic regimen one antiretroviral drug to which they had resistance mutations, 48.5% had genotypic resistance to two drugs of the therapeutic regimen and 21.2% to three drugs.

CONCLUSIONS

Most adherent patients failing on HAART carry drug resistant genotypes. These patients may constitute a reservoir of multidrug resistant HIV that may limit treatment options in the future.

Possible association between cytomegalovirus infection and gastrointestinal bleeding in hemophiliac patients

Cytomegalovirus (CMV) infection is of major concern in immunocompromised and immunosuppressed patients. Prior to the introduction of HIV-1 antibody screening and efficient virucidal processes to inactivate viruses, individuals with a factor VIII or factor IX deficiency had a high risk of contracting HIV-1 infection through the infusion of contaminated blood products. In addition, blood products were also frequently associated with alterations in immune function. This study investigated the frequency of active CMV infection and its clinical relevance in Brazilian hemophiliacs. One hundred hemophiliacs were screened for the presence of CMV-DNA in their blood using nested PCR. Twenty-five out of 100 patients (25%) were positive for CMV-DNA and 24 of these 100 patients (24%) were HIV-1 positive; 6 of these 24 (25%) were positive for CMV-DNA. A similar frequency was observed among HIV-1-negative patients. In 60 hemophiliacs, the clinical relevance of the CMV infection was assessed. Twenty-one patients were positive for CMV-DNA. Of these, 10 had gastrointestinal bleeding compared to only 9 of 39 patients who were CMV-DNA negative (p = 0.05; chi(2) test). These data indicate a high prevalence of active CMV infection in Brazilian hemophiliac patients, irrespective of whether the patients were or were not infected by HIV-1. There was a possible association between the presence of CMV and the occurrence of gastrointestinal bleeding.

Hypnotic, anticonvulsant and muscle relaxant effects of Rubus brasiliensis. Involvement of GABA(A)-system

Rubus brasiliensis hexanic fraction induced anxiolysis in rodents, which was reversed by flumazenil, a specific GABA(A)-benzodiazepine receptor antagonist (Nogueira et al., 1998a,b). Then, we investigated if this hexanic fraction was able to induce hypnotic, anticonvulsant and muscle relaxant effects, and the involvement of GABA(A)-system. The hexanic fraction (50, 100, 150 and 300 mg/kg, vo) was administered to male Swiss mice, 30 min before the tests. Only the dose of 300 mg/kg of this fraction decreased the latency and increased sleeping time in the barbituric-hypnosis test (sodium pentobarbital, 30 mg/kg, ip), prevented the pentylenetetrazol seizures (70 mg/kg, ip) and induced muscle relaxant (inclined plane) in 100% of animals. These effects were reversed by flumazenil (3 mg/kg, ip).

IN CONCLUSION

(1) R. brasiliensis hexanic fraction induced hypnotic, anticonvulsant and muscle relaxant effects, in mice, and the GABA(A)-benzodiazepine receptor may play an important role in the effects of this fraction; (2) it is strongly suggested that this fraction contains a benzodiazepine-like principle.

Involvement of GABA(A)-benzodiazepine receptor in the anxiolytic effect induced by hexanic fraction of Rubus brasiliensis

To investigate the ability of hexanic ethanolic fraction of Rubus brasiliensis Martius (Roseceae), to induce anxiolytic effect and also the possible involvement of the GABA(A)-benzodiazepine receptor complex, male Wistar rats and Swiss mice behaviour were tested in the elevated plus maze (EPM). All the doses of the extract, 50, 100 and 150 mg/kg, administered per gavage (vo), 30 min before the behavioural evaluation, induced an anxiolytic effect expressed by: increased number of entries in and time spent in the open arms and percentage of open arm entries; and decreased number of entries and time spent in the closed arms. The treatment of mice with flumazenil (Ro 15-1788), 0.5, 1.0 and 1.5 mg/kg, i.p., 15-min before the administration of hexanic fraction, 100 mg/kg, vo, blocked the hexanic fraction-induced anxiolytic effect. The LD50 for the hexanic fraction was 1512 mg/kg. In conclusion, it was shown that the hexanic fraction of R. brasiliensis induced an anxiolytic effect in rats and mice. This effect can be attributed to a liposoluble principle with low toxicity which may be acting as an agonist on GABA(A)-benzodiazepine receptor complex.

Anxiolytic effect of Rubus brasilensis in rats and mice

The aim of the present work was to investigate if infuse and ethanolic extracts (aqueous, butanolic and wax fractions) of Rubus brasiliensis Martius (Rosaceae) induce anxiolytic effect. The extracts were administered to male Wistar rats and Swiss mice per oral route, at 50, 100 and 150 mg/kg, 30 min before the behavioral evaluation in the elevated plus maze (EPM). Both infuse and wax ethanolic fraction at the dosage 150 mg/kg, vo, increased the number and the percentage of open arm entries of rats and mice. The aqueous and butanolic fractions, obtained from ethanolic extract, failed to induce anxiolytic effect. The treatment of mice with flumazenil (Ro 15-1788), 1.5, 2.0 and 2.5 mg/kg, i.p., 15-min before the administration of infuse or wax fraction, 150 mg/kg, vo, blocked the infuse or wax fraction-induced anxiolytic effect. The LD50 for the wax fraction was 1000 mg/kg. In conclusion, the infuse and wax ethanolic fraction of R. brasiliensis present anxiolytic effect in rats and mice. In addition, it is suggested that the anxiolytic effect may be attributed at least to one liposoluble principle with low acute toxicity which may be acting as an agonist on GABA(A)-benzodiazepine receptor complex.

Activation of TRK genes in Ewing's sarcoma. Trk A receptor expression linked to neural differentiation

Trk receptors have been identified by immunohistochemical methods in primitive neuroectodermal tumor (PNET)/Ewing's sarcoma (ES). However, the presence of different members of the Trk family of receptors in PNET/ES has not been specified. We have examined whether Trk A, B, and C receptors are specifically expressed in ES both with and without features of neural differentiation. Ten ES tumors (five primary tumors of bone and five extraosseous tumors transplanted into nude mice) were investigated for expression of Trk receptors by immunohistochemistry and reverse transcription-polymerase chain reaction. One primary ES and the five grafted ES tumors exhibited signs of neural differentiation; the remaining four primaries were undifferentiated ES. Other tumor types were analyzed as controls; they included three neuroblastomas (NB), two lymphomas, and single cases of pheochromocytoma (PHEO), schwannoma (SCHW), osteosarcoma, and carcinoma of breast, colon, and kidney. Trk receptors were detected in paraffin-embedded tumor tissue sections by means of a pan-Trk polyclonal antibody raised against the 14 carboxy-terminal residues of gp140trk, and trk A, B, and C transcripts were specifically detected by polymerase chain reaction-based amplification on cDNAs derived from tumor RNA with MuLV reverse transcriptase. Reactivity to the pan-Trk antibody was exhibited by six ES tumors, the three NBs, and the single PHEO and SCHW cases; immunoreactivity was restricted to differentiated tumors, in the case of ES. Tumor types positive for immunostaining were also distinguished by containing transcripts of TRK genes. However, the trk A, B, and C expression pattern of ES differed from that of NBs, PHEO, and SCHW. Transcripts of trk A, B, and C were detected in seven, four, and one case of ES, respectively, and in five, two, and five cases of NB, PHEO, and SCHW, respectively. Interestingly, all differentiated ES tumors contained trk A transcripts. Tumors of neuroectodermal phenotype and/or derivation were thus characterized by a distinct consensus expression pattern: trk A+/B-/C+ for differentiated ES and trk A+/B-/C+ for NB-PHEO-SCHW. These results indicate that the TRK gene family is frequently activated in ES; they also suggest that Trk A receptor is a feature of ES with neural differentiation, whereas Trk B and C receptors seem to be present in undifferentiated ES.

[Streptokinase in severe pulmonary thromboembolism]

Severe pulmonary embolism (PE) was treated with streptokinase in four patients, three men and one woman, age 38 to 72 (mean = 53 +/- 14) years. Before the thrombolytic therapy, all patients had pulmonary angiogram and hemodynamic parameters analyzed. The drug was infused through the distal lumen of the Swan-Ganz catheter at the pulmonary artery trunk. The initial dosage was 250,000 units "in bolus" and 100,000 units in 24 to 72 hours. The time interval between the symptoms and treatment had ranged from 2 hours to 5 days. The results are analyzed as follow: reduction on right atrial pressure, mean pulmonary pressure, pulmonary vascular resistance, an increase in the stroke volume and cardiac output. In two cases we observed total lysis, in one partial lysis and one patient died from severe form of PE and late infusion of SK. Reinfusion of the drug was necessary in one patient that had PE recurrence with reliable final result. Finally, no one had severe bleeding despite the use of the intrapulmonary catheter.

Adenylate cyclase activity in microdissected rat liver tissue: periportal to pericentral activity gradient

Adenylate cyclase activity was measured in microdissected samples from lyophilized cryostat sections of rat liver by means of an improved assay. Livers were obtained from adult Sprague-Dawley rats fasted for 22 hr. Adenylate cyclase activities, basal and those elicited by various agents, were determined in dissected samples from periportal and pericentral regions of the classic liver lobule. In all samples, enzyme activity was strongly stimulated by glucagon, cholera toxin, guanosine-5'-O-(3-thiotriphosphate), sodium fluoride and forskolin. The beta-adrenergic agonist isoproterenol produced very weak, if any, enzyme stimulation. Angiotensin II did not inhibit the activity elicited by lithium chloride and GTP at high concentrations, and pertussis toxin did not enhance the GTP-stimulated activity. We observed a periportal-to-pericentral gradient for basal and agent-stimulated activities.

Influence of angiotensin converting enzyme inhibition on exercise performance and clinical symptoms in chronic heart failure: a multicentre, double-blind, placebo-controlled trial

One hundred and seven patients with chronic heart failure (NYHA class II to IV) stabilized on digitalis and/or diuretics, recruited from 11 centres were randomized into a double-blind, placebo-controlled study to assess the effect of 12 weeks of cilazapril therapy on exercise tolerance and clinical status. Thirty-five patients were randomized to placebo and 72 to cilazapril at a starting dose of 1 mg daily; titration to cilazapril 2.5 mg at week 4 and 5 mg at week 8 (or matching placebo) was carried out in patients who did not improve clinically. Demographic characteristics, including exercise test duration increased from 402 s (+/- 17 SEM) at baseline to 462 s (+/- 19 SEM) at week 12 for the cilazapril group (+15%) and from 405 s (+/- 23 SEM) at baseline to 408 s (+/- 30 SEM) at week 12 in patients on placebo (+1%) (P < 0.001). In the placebo group, patients able to exercise for more than 6 min at baseline showed an increase in exercise duration at week 12 while those able to exercise for up to 6 min at baseline showed a decrease (P = ns). In contrast, cilazapril-treated patients showed an increase in exercise tolerance regardless of baseline exercise test duration; patients with the most impaired exercise tolerance at baseline showed a greater improvement than patients with mildly impaired baseline exercise tolerance (P < 0.05 vs placebo). NYHA class improved by at least one grade in 51% of the cilazapril group vs 32% in the placebo group (P = ns). At the end of the trial, 15% of the patients were non-responders on cilazapril vs 41% on placebo (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Experimental models of kidney tumors

We here present in outline some outstanding results on the animal models of renal tumors submitted to the highest attention, which include two kinds of epithelial neoplasms: those developed from the epithelium lining each the renal tubules (renal cell tumors) and pelvis; the mesenchymal tumor of rat; and tumors with embryonal appearance: the nephroblastoma as well as the variant of it known as the estrogen-induced tumor in the hamster. The review deals with methods for tumor induction and the pathobiology of tumors, the latter mainly focused on the identification of the precise types of renal cells committed in tumor origin. The existence of closely related counterparts of these animal tumors in man is also emphasized, by representing a situation of great potentiality, already exploited, to improve understanding of both the nature and development of renal tumors in man.

Cellular and molecular mechanisms of renal carcinogenesis induced by avian erythroblastosis virus

Besides erythroleukemias and sarcomas, avian erythroblastosis virus strain ES4 (AEV-ES4) induces renal adenocarcinomas (RCas) in chickens. To search for the cells of origin and the mechanism of the development of RCas, we investigated the RCas produced by td359AEV, a mutant of AEV-ES4 which lacks a leukemogenic effect, but which is sarcomagenic. Spindle cell sarcomas in various organs and RCas developed in a high number of chickens inoculated with td359AEV. RCas were tubulo-cystopapillary structures of basophilic cells and originated only from differentiated principal cells (PCs) of the renal collecting duct system. The origin of tumors from PCs was indicated by connections of tumor epithelium to segments of the collecting duct system, including connecting tubules and cortical and medullary collecting ducts. Tumor cells showed typical mucopolysaccharide-containing vacuoles which are characteristic of chicken PCs. Viral particles were observed throughout the kidney. Moreover, the highest numbers of particles as well as budding-images of them were seen (apart from tumor cells) in podocytes and distal tubule cells which did not undergo neoplastic change. The susceptibility of PCs to undergo neoplastic transformation could not be related to a particular activation state of the erbB gene, in view of the fact that cerbB expression was detected by in situ hybridization in the epithelium lining the Bowmann's capsule and the entire renal tubule system. From data of Northern blot and in situ hybridization techniques, it was suggested that the neoplastic transformation of PCs was elicited by overexpression of the v-erbB oncogene, a feature of tumor cells already detected in renal tubules lined by basophilic proliferating cells, the first stages of renal carcinogenesis induced by td359AEV. According to Southern blot analysis, td359AEV proviruses were randomly inserted in tumor DNAs and the RCas were polyclonal in nature.

Rat hepatocarcinogenesis induced by N-nitrosodiethylamine and N-nitrosomorpholine continuously administered at low doses. From basophilic areas of hepatocytes to hepatocellular tumors

The development of hepatocellular tumors was investigated with histological, histochemical, and morphometrical methods in male Sprague-Dawley rats continuously administered N-nitrosodiethylamine (DEN) or N-nitrosomorpholine (NNM) in the drinking water at low doses (0.5 mg DEN/100 ml; 1 mg NNM/100 ml). Groups of control, DEN-, and NNM-treated rats were investigated at 5-week intervals. Similar results were obtained in DEN- and NNM-treated rats. Two types of areas composed of basophilic or glycogenotic hepatocytes were observed preceding the appearance of hepatocellular adenomas and carcinomas. Besides their cytologic differences, the basophilic and glycogenotic areas induced displayed distinct histochemical features. Both types of areas were detected simultaneously and increased in parallel with time to a similar incidence, but basophilic areas reached larger sizes than the glycogenotic ones. Furthermore, each type of area, which clustered around and along efferent veins, was differently linked to tumorigenesis. Basophilic areas frequently developed into basophilic adenomas and trabecular carcinomas through a characteristic sequence. Early basophilic areas consisted of hepatocytes with lamellar cytoplasmic hyperbasophilia and exhibited the normal laminar liver structure. With time, an increasing number of basophilic areas also contained hepatocytes with powdered diffuse hyperbasophilia, which frequently were arranged in thick trabeculae, showed abundant mitotic figures, and invaded efferent veins. Neither such signs of malignancy nor conversion into basophilic areas or tumors could be established for areas of clear and acidophilic glycogenotic hepatocytes. However, a few small glycogenotic adenomas probably developed from glycogenotic areas. Our data thus underline the central role of basophilic areas for hepatocarcinogenesis. Moreover, taking into account the data from other experiments, it seems likely that although glycogenotic areas may be associated with the application of some carcinogens at high doses, they are not obligatory precursors of hepatocellular tumors.

Collecting duct origin of rat renal clear cell tumors

The renal tubular segment from which clear cell tumors originate was investigated in the kidneys of rats treated with N-nitrosomorpholine. This tumor type, which in the rat closely resembles that in man, is made up of clear and granular acidophilic cells and arises from tubules lined by clear cells. The tubular origin of the tumors was established in serial sections by demonstrating connections between both clear cell tumors and tubules lined by clear cells, and renal tubules of normal appearance. In 45 clear cell lesions (17 tumors and 28 tubules) one or more such connections were identified which belonged to the collecting system. In accordance with their localisation in the kidney, the clear cell lesions were connected predominantly to tubules of the cortical collecting system and occasionally to outer medullary collecting ducts. As previously reported, oncocytic tubules and microoncocytomas were observed to originate from the same portions of the collecting system. Rarely, microadenomas and tubules consisting of both oncocytes and clear or granular acidophilic cells were also observed in the kidneys studied.

Cellular origin of rat renal oncocytoma

The cellular origin of the rat renal oncocytoma was studied by light and electron microscopy in rats treated with N-nitrosomorpholine. The oncocytomas which appeared as small solid masses or cysts developed from tubules lined by oncocytes. Rats treated with N-nitrosomorpholine showed a number of oncocytomas and many oncocytic tubules, the incidence of which increased with time. A small number of oncocytic tubules but no oncocytomas were observed in the oldest control rats. Two major types of oncocytes were detected in the oncocytic lesions. Whereas some oncocytes contain only small round mitochondria, most oncocytes exhibited both small and unusually large pleomorphic mitochondria. The tubular origin of the oncocytic lesions was established precisely in serial sections. Numerous transitions of both oncocytomas and oncocytic tubules into renal tubules of normal appearance indicated that oncocytic lesions developed frequently from the cortical collecting duct system, including the connecting tubule, and occasionally from the outer medullary collecting duct. Mitochondrial changes similar to those of fully developed oncocytes were recognized in principal and intercalated cells of these segments, indicating the involvement of these cell types in the genesis of the renal oncocytoma.

Rat renal carcinogenesis after chronic simultaneous exposure to lead acetate and N-nitrosodiethylamine

Chronic oral administration of lead acetate and/or N-nitrosodiethylamine to rats produces three different types of renal cell tumors composed of basophilic, chromophobic or oncocytic cells. The most frequent tumor, often visible macroscopically, is made up of basophilic cells and forms tubular, cystic, pseudo-papillary or solid structures; it may show considerable cellular atypia but does not metastasize or invade the surrounding parenchyma. Chromophobic and oncocytic tumors are rare and can only be detected with the microscope; they usually form cystic or solid structures. Basophilic and chromophobic tumors arise from specific segments of the proximal tubules, characteristic for each carcinogen: P2, P3C and P3M for lead acetate; P2 and P3C for N-nitrosodiethylamine. Karyomegalia in proximal tubule cells appears to be irrelevant in renal carcinogenesis. However, the appearance of basophilic and chromophobic cells in P2, P3C and P3M segments is considered to be an early change in tumor development. Oncocytic microadenomas originate from collecting ducts showing focal oncocytic transformation. Synergistic or inhibitory effects are not observed after chronic simultaneous administration of lead acetate and N-nitrosodiethylamine, although both carcinogens act in common on P2 and P3C proximal tubule segments.

Renal oncocytoma: origin from the collecting duct

The histo- and cytogenesis of two cases of renal oncocytoma have been studied by cytomorphological and cytochemical methods. Transitions from collecting ducts into oncocytic tubules were observed at the light and electron microscopic levels. The fine structure of the oncocytes in tubules and tumors is described in detail. Cytochemically, the oncocytic tubules and oncocytomas share many characteristics with the distal nephron, especially the collecting ducts. A striking difference is the enhanced activity of succinic dehydrogenase which corresponds to the increase in the number of mitochondria in oncocytes. All the results suggest that renal oncocytoma originates from the collecting duct.