Liliana Borges de Menezes

Seasonal dynamics of Rhipicephalus sanguineus (Acari: Ixodidae) in dogs from a police unit in Goiânia, Goiás, Brazil

The seasonal dynamics of Rhipicephalus sanguineus ticks was developed in dogs from a Police Unit in Goiânia, Goias, Brazil, from July 2001 to July 2002. The study was carried out on seven naturally infested dogs (two English Cocker Spaniels and five mongrel dogs), with ages between six months and 10 years. Every two weeks, the numbers of feeding larvae, nymphs, and adults were determined. Dogs showing infestation levels above 500 adult ticks received three acaricide treatments. Considering that the treatments had affected the development of some peaking populations of ticks, it was inferred the occurrence of the following peaks: - larvae (four peaks): from August to November, from November to February, from March to May, and from May to July; - nymphs (five peaks): from July to September, from October to December, from December to February, from March to May, and from June to July; - adults (four peaks): from July to October, from October to January, from January to March, and from April to July. The occurrence of these consecutive peaks of activity of each stage of R. sanguineus may indicate that this tick can develop up to four generations per year in Goiânia. On the other hand, if the acaricide treatment did not interfere with the development of R. sanguineus peaks, more than four peaks of each stage have occurred on the dogs. In this case, it is acceptable to infer that more than one population of R. sanguineus was developing within the kennel concomitantly. The mean numbers of each tick stage was similar in the different seasons. The main attachment sites were located on the neck, chest, forelegs, armpits, ears, between toes and on the head. The number of adult ticks feeding on English Cocker Spaniel dogs was 1.4 to 11.5 times higher than that feeding on mongrel dogs.

Use of chitosan membrane associated with polypropylene mesh to prevent peritoneal adhesion in rats.

The correction of wall abdominal defects often requires the use of implants such as polypropylene meshes. In spite of presenting good tissue acceptance, these biomaterials can migrate to adjacent viscera, promote enterocutaneos fistulas, tissue adherence and visceral erosions. In this work, the barrier effect of chitosan films associated with polypropylene meshes on adhesion formation experimentally induced in Wistar rats was evaluated. The animals were divided into two groups with 10 animals each. Animals in the CPP group were implanted with chitosan films associated with polypropylene meshes, whereas the ones in the PP group received only polypropylene meshes. After 8 days, the animals were submitted to euthanasia using CO(2) and a descriptive study focusing adhesion formation, visceral involvement with sutures and mesh peritonization was performed. Also, subimplanted material was collected for histopathology analysis. The results showed that the CPP group presented weak adhesions to the omentum over the stitch knots in eight animals. In all animals, the meshes were peritonized, not allowing their visualization after removing the chitosan films. In the PP group, six animals presented intestinal adhesions to the meshes and, in one of them, hepatic adhesion to the mesh was observed, besides omentum adhesion on more than 50% of the mesh area. The protective effect of chitosan films when sutured over polypropylene meshes, as well as no exacerbation of inflammation associated to the peritoneal lesions was statistically demonstrated. Therefore, chitosan films can indeed minimize the formation of peritoneal adhesions induced by polypropylene meshes in rats.

The Fate of the Tumor in the Hands of Microenvironment: Role of TAMs and mTOR Pathway

Since 2000, written with elegance and accuracy, Hanahan and Weinberg have proposed six major hallmarks of cancer and, together, they provide great advances to the understanding of tumoral biology. Our knowledge about tumor behavior has improved and the investigators have now recognized that inflammatory microenvironment may be a new feature for the tumor entities. Macrophages are considered as an important component of tumoral microenvironment. Biologically, two forms of activated macrophages can be observed: classically activated macrophages (M1) and alternative activated macrophages (M2). Despite the canonical pathways that control this puzzle of macrophages polarization, recently, mTOR signaling pathway has been implicated as an important piece in determining the metabolic and functional differentiation of M1 and M2 profiles. Currently, it is believed that macrophages related to tumoral microenvironment present an “M2-like” feature promoting an immunosuppressive microenvironment enhancing tumoral angiogenesis, growth, and metastasis. In the present review we discuss the role of macrophages in the tumor microenvironment and the role of mTOR pathway in M1 and M2 differentiation. We also discuss the recent findings in M1 and M2 polarization as a possible target in the cancer therapy.

Avaliação do efeito da clorpromazina sobre a função renal de cães submetidos à isquemia e reperfusão

Renal ischemia may occur in different situations such as vascular or renal surgery and also in renal transplantation. This study evaluates renal function in dogs submitted to ischemia and reperfusion after chlorpromazine application. Twelve adult mongrel dogs were distributed into two groups with six animals each. Group A was composed of dogs submitted to renal ischemia and reperfusion without previous administration of chlorpromazine. Group B was composed of dogs with renal ischemia and reperfusion previously treated with chlorpromazine. In order to evaluate the possible ischemia/reperfusion late effects, blood and urine samples were sampled in four different times: Before ischemia, early stages of reperfusion, 120 minutes after reperfusion, and every week until 28th day postsurgery. Renal function was evaluated by clinical examination, serum urea and creatinine levels and urinary GGT activity. PU/CU and GGT urinary activity were more sensitive in detecting acute tubular injury than routine urine examination because these variables showed earlier changes. Based on urinalysis, urea and creatinine serum levels plus urinary excretion of GGT and PU/CU, no evidences of protective action of chlorpromazine were observed.

Evaluation of peritoneal adhesions formation and tissue response to polypropylene - poli (2-hydroxyethyl methacrylate)-(polyHEMA) implant on rats' abdominal wall.

PURPOSE To verify if the composit poli (2-hydroxyethyl methacrylate)-PolyHEMA/polypropylene mesh implanted in the female rats abdominal wall could be suitable for the prevention of peritoneal adhesions, and for the evaluation of the tecidual response produced by this biomaterial. METHODS Polypropylene meshes (Group PP, n=20) and polypropylene meshes coated with a layer of poli (2-hydroxyethyl methacrylate)-PolyHEMA (Group PH, n=20) were implanted on the abdominal wall of Wistar female rats. Ten animals from each group were submitted to euthanasia at 15 and 30 days of the postoperative period. RESULTS The animals from the group PP presented visceral adhesions on the mesh surface, which was not observed in the ones from group PH. At the histopathological examination foreign body response was observed in both groups, whilst there was a greater intensity of inflammatory response in group PH on both moments. CONCLUSION The poli (2-hydroxyethyl methacrylate) polyHEMA hydrogel associated to polypropylene mesh reduces visceral adhesion formation in rats, although it may be associated to greater inflammatory reaction.

Hernioplastia experimental em coelhos por meio de cartilagem auricular bovina conservada em glutaraldeído

The auricular cartilage preserved in 4% glutaraldehyde was used for experimental hernioplasty in six male, adult, New Zealand rabbits. To create an incision hernia, an elliptic tissue fragment three centimeter-long and one-centimeter wide was removed at a point centrally located from the first incision, embracing fascia and muscle tissue, from the area of umbilical scar. Animals were euthanized, two at a time, 15, 30, or 45 days after surgery. In the animals euthanized after 15 days focal areas of inflammation were observed, characterized by abscesses and fistulas. The histological section showed areas of inflammation and necrosis next to the periphery of the graft. In the animals euthanized after 30 days, there was no evidence of clinical alterations. Microscopic diagnosis of one of these animals showed intense fibroblastic proliferation, moderate neovascularization and inflammatory cells, predominantly mononuclear. One of the animals submitted to euthanasia at 45 days presented at necropsy adherence of bowel to the graft and impaired reconstitution of the parietal peritoneum. It is possible to infer that the grafted material presented satisfactory compatibility with the receptor tissue. Thus, it may be concluded that auricular bovine cartilage grafts preserved in 4% glutaraldehyde in experimental hernioplasty in rabbits presented evidence of good tissue integration and healing, with no elimination of the grafted material.

Característica leucocitária, relação albumina/globulina, proteína plasmática e fibrinogênio de bovinos da raça Nelore, confinados e terminados a pasto

This research aimed to evaluate the changes in the white blood cell count and some serum proteins of confined cattle (CC) and grass cattle (GC). From the 120 blood samples collected, 60 were obtained from confined Nelore male bovines and 60 from animals with the same characteristics but managed extensively. Samples were obtained at the moment of slaughter. Parameters studied were the white blood cell count, serum albumin/globulin ratio and concentration of plasma fibrinogen. Descriptive statistics was used in the analysis of the data, and the averages, standard deviation and coefficient of variation calculated for all parameters evaluated. The comparisons between averages were made by non-parametric test. The grazing cattle showed higher levels of globulin and fibrinogen when compared to the confined ones (globulin: GC=3.29g dL-1±0.76; CC=2.99g dL-1±0.60 and Fibrinogen: GC=872mg dL

2-hydroxyethyl methacrylate composite - polypropylene mesh for preventing peritoneal adhesions in female dogs.

PURPOSE To evaluate whether the lining facing the visceral side of polypropylene mesh made with 2-hydroxyethyl methacrylate (p(HEMA)) hydrogel could avoid peritoneal adhesion in female dogs. METHODS Eight animals (group PP) had a polypropylene mesh implanted to correct a defect in the rectal abdominal muscle, whereas in the other group (group PH) the polypropylene mesh was coated with p(HEMA) composite on the surface facing the peritoneal area. RESULTS Adhesions were observed on the mesh in 62.5% of the PP group. In the PH group adhesions were present only on the suture lines. CONCLUSION p(HEMA) hydrogel was well tolerated and effective in avoiding visceral and omental adhesions on the surface of the polypropylene mesh.

Improving peptide quantification in chitosan nanoparticles

Abstract The objective of the present study was to evaluate different methodologies for peptide quantification in the supernatant of chitosan nanoparticles by removing the unliked polymer in the suspension. The ionic gelation method was used to prepare the chitosan nanoparticles encapsulating a 5.3 kDa peptide. Three different methodologies for the processment of the solutions were compared before subjecting the samples to the Bradford protocol or Qubit® kit for protein detection. For the quantification, it was necessary to create a standard peptide curve using different peptide concentrations. The suitable standard curve would be one in which the peptide was diluted in the empty chitosan supernatant (obtained after nanoparticles centrifugation) or in the filtrate of the empty chitosan supernatant. Our results indicated the safest methodology tested for peptide quantification in the supernatant chitosan nanoparticles was filtering the solution before subjecting the sample to the Bradford assay.

Estudo clínico e histológico das pálpebras e conjuntiva hígidas submetidas ao tratamento tópico com soluções anestésicas em coelhos

This work aimed to evaluate commercial presentations of anesthetic eye drops in sixty three New Zealand rabbits which were separated equally in three groups (G1, G2 and G3). The G1 group was treated with 0.5% proparacaine chloridrate eye drop, G2 group with 1% tetracaine chloridrate associated with 0.1% phenylephrine eye drop and G3 group with 0.9% physiologic solution eye drop. All of them received one drop in each eye six times a day. Each group was subdivided into three subgroups (seven rabbits), which are treated for 3, 7 and 15 days. At the end of each treatment, two animals in each subgroup were subject to euthanasia, for the purpose of conjunctiva, eyelids and third eyelids histological evaluation. At the clinical exam, different grades of episcleritis were found in all rabbits in G2 group and only in 17.8% of the rabbits in G1 group. Eye and eyelid histologic evaluation of G2 group revealed an upgrade of goblet cells and eosinophil number, lymphoid follicle proliferation and increase of interstitial space in the eyelids. We could conclude that 1% tetracaine associated with 0.1% phenylephrine eye drop caused more eyelid and ocular conjunctiva toxicity than 0.5% proparacaine eye drop.