Acid phosphatase and cathepsin D are active expressed enzymes in the placenta of the cat.

Enzymes are crucial for the metabolism of macromolecular substrates. In the great majority of cells, most enzymes are constitutive. Nevertheless, inducible enzymes can predominate, determining specialized cell functions. Within this context, histochemistry/immunohistochemistry and biochemistry were used to investigate expression of peroxidase and reduced nicotinamide-adenine dinucleotide phosphate (NADPH)-oxidase, as well as the expression and activity of cathepsin D and acid phosphatase, in trophoblast cells within the endotheliochorial labyrinth and marginal hematoma of the term cat placenta. In the marginal hematoma, elevated Cathepsin D expression and activity was accompanied by erythrophagocytosis. In contrast, acid phosphatase activity was much more intense in the labyrinth, where metabolic exchanges occur. Peroxidase and NAD(P)H-oxidase were predominantly active in trophoblast cells within endosomal vesicles of different placental compartments, indicating that, although reactive oxygen species might participate in endosomal/lysosomal processes, they are not territorially specific or functional markers. These findings highlight differential characteristics of cathepsin D and acid phosphatase activity within each placental compartment, thereby contributing to the comprehension of the territorial role played by the placenta and facilitating future metabolic studies.

Nitric oxide modulates eosinophil infiltration in antigen-induced airway inflammation in rats.

The influence of nitric oxide (NO) on eosinophil infiltration into the airways was investigated in rats actively sensitized with ovalbumin. The animals were treated chronically with the NO synthase inhibitor, N omega-Nitro-L-arginine methyl ester (L-NAME; 75 mumol rat-1 day-1), for 4 weeks. Bronchoalveolar lavage was performed at 6, 24, 48 and 72 h after intratracheal injection of ovalbumin. Intratracheal challenge of the sensitized rats with ovalbumin caused a significant increase in total leucocyte infiltration in bronchoalveolar lavage fluid both 24 and 48 h post-ovalbumin injection. Neutrophils and eosinophils peaked, respectively, at 24 h (29%) and 48 h (30%) in bronchoalveolar lavage fluid whereas the mononuclear cell did not differ significantly from the counts in non-sensitized rats at any time. At both 6 and 24 h post-ovalbumin injection, the chronic treatment of the animals with L-NAME affected neither the total nor the differential leucocyte content. However, at 48 h post-ovalbumin challenge, the total cell count was reduced by approximately 48% in the L-NAME-treated animals and this was associated with a marked inhibition (81%) of the eosinophil influx. Histological examination of the lungs from these animals (48 h post-ovalbumin challenge) also showed a prominent reduction (69.5%; P < 0.05) of the eosinophil infiltration in the respiratory segments. Our results demonstrate that NO plays a pivotal role in the eosinophil infiltration in airways of actively sensitized rats.

Post-implantation mouse embryos have the capability to generate and release reactive oxygen species.

The capability of the mouse embryo to generate reactive oxygen species (ROS) was examined. Post-implantation embryos were carefully harvested on Day 8 of pregnancy and the production of ROS was quantified using luminol-sensitized chemiluminescence. The embryos were stimulated with either phorbol myristate acetate (PMA) or all-trans-retinal (retinal) and the reaction kinetics were followed over 10 min. ROS secretion was directly proportional to the number of embryos and was suppressed 56% by superoxide dismutase (SOD), 25% by mannitol and as little as 16% by catalase. Embryos deprived of trophoblast showed no light emission suggesting that the source of ROS generation is the trophoblast. Dihydronicotinamide adenine dinucleotide (NADH)-dependent oxidase activity in the plasma membrane of the trophoblast surface was demonstrated by cytochemical methods. The release of ROS into the extracellular medium during the phagocytic process has been related to the cytolytic effect exhibited by these molecules and, perhaps by this means, the trophoblast can play an active role in the phagocytosis of maternal cells during the process of embryo implantation.

[Polyneuropathy caused by parathion: clinical, electrophysiologic and histologic studies of a case]. / Polineuropatia por parathion: estudo clínico, eletrofisiológico e histológico de um caso.

A case of 38 year old man who worked with organochlorinated and Parathion during 5 years is reported. His follow-up was up to 2 years. The onset of the disease was characterized by cholinergic signs, headache, loss of weight, trembling, miokimias, fasciculations, ataxia, myotonic phenomena (in hands only) and motor sensitive peripheral polyneuropathy (affecting the lower limbs symmetrically). Low concentrations of blood cholinesterases confirmed the etiology. Myotonic phenomena disappeared spontaneously 6 months after the initial observation. One year later, the concentration of erythrocyte acetylcholinesterase was found to be low and plasma cholinesterase was normal, suggesting that the patient was carrier of a congenital deficiency of acetylcholinesterase. In literature relationship between myotonia and intoxication due to organophosphorus was not found. The whole clinical picture, cholinergic symptoms, transitory phenomena and spontaneous motor activity could be explained by an excess of acetylcholine. Electromyography (EMG) in the first observation showed neuromuscular transmission blocking characterized by deficiency or absence of voluntary activity, unexcitability of fibular nerves, with fibrillations and positive peaks as described previously with Mipafox (another organophosphorus agent). During 2 years of observation numerous end-plates potentials of muscular fibres persisted in the EMG. A progressive increase in voluntary activity showed by unit motor potential of almost normal amplitude and very increased duration was observed. No potentials of reinnervation were noted. The results of EMG were explained as disturbances of neuromuscular transmission associated with moderate signs of denervation. The Eaton-Lambert's test and the stimulation of a single unit motor potential confirmed disorder of neuromuscular synapses. The histochemistry of brachial biceps showed scattered atrophic and angulated type I and II fibres. Teased-fibres preparations showed nerve fibres with B, C, and G alterations as defined by Dyck et al. indicating axonal degeneration. These results were according to velocity of sensitive conduction. The conduction velocity of fibular nerves was strongly delayed during all the evolution indicating serious disorders of motor nerves myelin.(ABSTRACT TRUNCATED AT 400 WORDS)

[Muscular biopsy in myasthenia gravis: histochemical and morphometric study of 4 cases]. / Biopsia muscular em miastenia grave: estudo histoquímico e morfométrico de 4 casos.

Myasthenia gravis is a neuromuscular disease characterized by excessive fatigability of muscle function and particularly involves muscles innervated by the cranial nerves. It is believed that the defect is in the neuromuscular junction. The authors studied histochemical and morphometric findings in 4 patients with myasthenia gravis showing that the type II fibres were significantly smaller than the type I fibres.

[Ocular myopathy, Kiloh-Nevin type; study of a case with histochemical and ultrastructural changes]. / Miopatia ocular tipo Kiloh-Nevin; estudo de um caso com alteracões histoquímicas e ultraestruturais.

A non-familiar case of Kiloh-Nevin ocular myopathy with important histochemical and ultrastructural abnormalities is reported. The patient, a 43 year-old male presented with 10 year long, pregressive ocular ophtalmoplegia, myasthenic symptoms and severe muscular pain, an uncommon finding in this type of myopathy. The histochemical study showed muscular atrophy, mainly in type I fibres and a great amount of ragged-red fibres. Of particular interest, in this case, was the ultrastructural finding of severe mitochondrial abnormalities with a lot of inclusions in the cristae matrix; nevertheless these changes are not specific. The authors suggest a possible abnormality in the neuro-muscular transmission system and a genetically controlled enzimatic factor as responsible for the aethiology and pathogenesis of the Kiloh-Nevin ocular myopathy.

[McArdle's disease: a case report]. / Doença de McArdle: registro de caso.

This disease was described by McArdle as an inherited autosomal recessive affection characterized by glycogen storage with normal chain in the skeletal muscles, due to absence of myophosphorylase activity. Under a clinical aspect, excessive fatigability, cramps and myoglobinuria appear following physical exercise. A case of this disease in a 36-year-old male patient is reported. Failure of elevation of venous blood lactate after physical effort under anaerobic conditions, as well as muscle histochemistry, made diagnosis confirmation possible. The authors comment on the differential diagnosis between McArdle's disease and the other causes of myoglobinuria, specially phosphofructokinase and carnitine-palmityl-transferase deficiency.

[Myotubular myopathy: clinical, electrophysiological and histological study of a case]. / Miopatia miotubular: estudo clínico, eletrofisiológico e histológico de um caso.

A cases of myotubular myopathy in a 10 years old girl is reported. Clinically, palpebral ptosis, ocular movements limitation, facial diplegia, positivity of Gower's test, muscular hypotrophy distal, foot drop and deep absent reflexes were found. These signals were described by most of authors, besides symptoms referred, like partial urinary incontinency and frequent vomits. Reflexes H absents and teary in our patient were observed but were not described in the other cases of the literature. Routine laboratory tests were within normal limits; only aldolase was lightly elevated. In all muscles examined it was noted a spontaneous electromyographic activity with +- of 2,64 +/- 1,33 ms, 36,87 +/- 30,87 microV and 88,13 +/- 24,82 /s of frequency without characteristics of desenervation potentials of myoneural plates. The voluntary electromyographic activity was of myopathic pattern. A curve I/D made in the motor point of braquial biceps muscle was normal. The biopsy was made in the motor point of this muscle for histochemical, electron immunofluorescence and vital stain microscopy. The biopsy showed 35% of fibras with central nuclei, predominance and hypotrophy of type I fibres, in some of them there were not myofibrils in the central zone, and poor differentiation between the fibre types in oxidative enzymes reactions. The electron microscopy confirmed the histochemical studies. The direct immunofluorescence was positive in some fibres. The vital stain showed beaded subterminal motor fibres. The clinical, electromyographic and principally histological findings suggest a innervation congenital disorder of muscle fibres.

Participation of the mouse implanting trophoblast in nitric oxide production during pregnancy.

While considerable progress has been made in elucidating nitric oxide (NO) regulatory mechanisms in the later stages of gestation, much less is known about its synthesis and role during embryo implantation. Thus, to evaluate the participation of the trophoblast in the production of NO during this phase, this study focused on NADPH-diaphorase activity and the distribution of NO synthase isoforms (NOS) using immunohistochemistry in pre- and postimplantation mouse embryos in situ and in vitro, as well as on NO production itself, measured as total nitrite, in trophoblast culture supernatants (Griess reaction). No NADPH-diaphorase activity was found in preimplanting embryos except after culturing for at least 48 h, when a few trophoblastic giant cells were positive. Conversely, postimplantation trophoblast cells either lodged into the implantation chamber (in situ) or after culturing (in vitro) showed intense NADPH-diaphorase activity. Also in the postimplantation trophoblast, the endothelial and inducible NOS (eNOS and iNOS) isoforms were immunodetected, under both in situ and in vitro conditions, although in different patterns. Extracts of ectoplacental cone also revealed bands of 135 and 130 kDa on SDS-PAGE that reacted with anti-eNOS and anti-iNOS, respectively, on Western blot. Analysis of the culture supernatant demonstrated that the nitrite concentration was 1) proportional to the number of cultured trophoblast cells, 2) almost completely abolished in the presence of N(omega)-nitro-L-arginine methyl ester, and 3) increased 2-fold in cultures stimulated with gamma-interferon. These results strongly suggest the production of NO from constitutive and inducible isoforms of NOS by the implanting mouse trophoblast. They also emphasize the possibility of the participation of these cells in vasodilatation and angiogenesis, and in cytotoxic mechanisms involved in the intense phagocytosis of injured maternal cells, which occur during the implantation process.

NADPH-diaphorase activity and nitric oxide synthase isoforms in the trophoblast of Calomys callosus.

The pattern of expression of a variety of placental nitric oxide synthase isoforms has contributed to elucidating the regulatory mechanisms of nitric oxide (NO) synthesis during gestation. The maintenance of vascular tone, attenuation of vasoconstriction, prevention of platelet and leukocyte adhesion to the trophoblast surface, and possible participation in uterine blood flow seem to be the main functions of NO generated at the fetal-maternal interface in humans and mice. Extending this knowledge to other rodent species commonly used as laboratory animals, in this study we focus on NADPH-diaphorase activity and the distribution of nitric oxide synthase isoforms (NOS) in the trophoblast cells of Calomys callosus during different phases of pregnancy. NADPH-diaphorase activity was evaluated cytochemically and the presence of NOS isoforms detected by immunohistochemistry. These techniques were performed on pre- and postimplantation embryos in situ and in vitro, as well as in placentae on d 14 and 18 of pregnancy. Neither NADPH-diaphorase activity nor inducible or endothelial NOS isoforms were found in pre-implanting embryos except after culturing for at least 48 h, when some of the embryonic cells were positive for the diaphorase reaction. On d 6.5 of pregnancy, trophoblast cells showed intense diaphorase activity both in situ and under in vitro conditions. A positive reaction was also found in the different placental trophoblast cells on d 14 and 18 of pregnancy. The inducible NOS (iNOS) isoform, but not the endothelial isoform, was immunodetected in trophoblast cells from the placenta and from postimplantation embryos in situ and under in vitro conditions. These results strongly suggest the production of NO by the iNOS isoform in the trophoblast of Calomys callosus after embryo implantation. The data also emphasise a possible role for the trophoblast in producing and releasing cytotoxic molecules at the fetal-maternal interface.

Biopsia muscular em miastenia grave.Estudo histoquimico e morfometrico de 4 casos. / Muscular biopsy in myasthenia gravis. Histochemical and morphometric study of 4 cases

Miastenia grave e doenca neuromuscular caracterizada por excessiva fatigabilidade da juncao muscular e envolve, particularmente, musculos inervados por nervos cranianos. Acredita-se que o defeito esteja localizado na juncao neuromuscular. Os autores estudaram os achados histoquimicos e morfometricos em 4 pacientes com miastenia grave mostrando que as fibras do tipo II eram significativamente menores que as fibras do tipo I

Polineuropatia por parathion. Estudo clinico, eletrofisiologico e histologico de um caso. / Polyneuropathy caused by parathion: clinical, electrophysiologic and histologic studies of a case

Estudamos um paciente com quadro clinico rebelde, produzido por intoxicacao pelo parathion. Foi observado um fenomeno miotonico transitorio, nao descrito na literatura revisada. A constatacao de cifras de AchE eritrocitaria baixas e de colinesterase plasmatica normais, indicou que era portador de deficit congenito de AchE, esclarecendo-se a evolucao cronica do seu quadro. O fenomeno miotonico associado ao quadro clinico, eletrofisiologico, histologico e bioquimico fazem deste paciente um modelo clinico, de etiologia conhecida, da discutida sindrome de Isaacs

Miopatia miotubular: estudo clinico, etrophysiological and histological study so. / Myotubular myopathy: clinical,elecof a case

Sao apresentados os resultados dos exames clinicos, eletrofisiologicos e do estudo do ponto motor, da imunofluorescencia, da histoquimica e da ultramicroscopia da biopsia muscular de um caso de miopatia miotubular. Sao discutidos estes resultados em relacao aos achados de 56 casos desta molestia consignados na literatura ate 1978, sendo cada enfase a etiopatogenia