Advances in surface design and biomedical applications of magnetic nanoparticles.

Despite significant efforts by scientists in the development of advanced nanotechnology materials for smart diagnosis devices and drug delivery systems, the success of clinical trials remains largely elusive. In order to address this biomedical challenge, magnetic nanoparticles (MNPs) have gained attention as a promising candidate due to their theranostic properties, which allow the simultaneous treatment and diagnosis of a disease. Moreover, MNPs have advantageous characteristics such as a larger surface area, high surface-to-volume ratio, enhanced mobility, mass transference and, more notably, easy manipulation under external magnetic fields. Besides, certain magnetic particle types based on the magnetite (Fe3O4) phase have already been FDA-approved, demonstrating biocompatible and low toxicity. Typically, surface modification and/or functional group conjugation are required to prevent oxidation and particle aggregation. A wide range of inorganic and organic molecules have been utilized to coat the surface of MNPs, including surfactants, antibodies, synthetic and natural polymers, silica, metals, and various other substances. Furthermore, various strategies have been developed for the synthesis and surface functionalization of MNPs to enhance their colloidal stability, biocompatibility, good response to an external magnetic field, etc. Both uncoated MNPs and those coated with inorganic and organic compounds exhibit versatility, making them suitable for a range of applications such as drug delivery systems (DDS), magnetic hyperthermia, fluorescent biological labels, biodetection and magnetic resonance imaging (MRI). Thus, this review provides an update of recently published MNPs works, providing a current discussion regarding their strategies of synthesis and surface modifications, biomedical applications, and perspectives.

Morphological analysis of myocardial bridges and coronary arterial dominance in northeast Brazil.

BACKGROUND: Coronary arterial dominance and myocardial bridges have clinical implications, since a left dominant pattern associated to the presence of myocardial bridges is often associated to a higher incidence of arteriosclerosis and higher mortality by myocardial infarction. OBJECTIVE: To determine the presence and position of myocardial bridges and their relation with coronary arterial dominance. METHODS: Fifty-seven human cadaveric hearts were analyzed into three groups, as follows: right dominance; left dominance; codominance. Each group was then divided into two subgroups: with or without myocardial bridges. Finally, each subgroup with myocardial bridges was classified according to the position of the myocardial bridge according to the main axis of the heart (proximal, middle and distal third). RESULTS: The right dominance occurred in most hearts (30 hearts-52,6%). Twenty-three myocardial bridges (40,3%) were identified and mostly occurred on left dominant hearts (22,8%). The pattern of coronary dominance presented a statistically significant correlation with the presence of myocardial bridges (P=0.048). The middle third of the heart axis showed the highest occurrence of myocardial bridges. CONCLUSION: These findings suggest there is a clear relationship between the presence of myocardial bridges and left dominant pattern. Middle third of the heart axis present the higher occurrence of myocardial bridges. Knowledge of the myocardial bridges morphology is of great clinical significance, improving patient care.

Non-specific effects of BCG in protozoal infections: tegumentary leishmaniasis and malaria.

BACKGROUND: Leishmaniasis and malaria are major causes of illness in the poorest countries. In the absence of efficient strategies to prevent infections and to control the transmission of the parasites by insect vectors, treatment relies on drug therapy. Vaccine development continues on several fronts; however none of the candidates developed has so far been shown to provide long-lasting protection at a population level. Because the bacillus Calmette-Guérin (BCG) vaccine can induce heterologous protective effects, we hypothesize that BCG has beneficial effects in the control of tegumentary leishmaniasis (TL) and malaria. AIMS: In this review we describe evidence for the protective efficacy of BCG against tegumentary leishmaniasis and malaria in humans. SOURCES: Relevant data from peer-reviewed scientific literature published on Pubmed up to January 2019 were examined. CONTENT: From experimental animal and various human studies with BCG and one recent randomized malaria trial there is evidence that BCG has beneficial effects in Leishmania spp. and Plasmodium falciparum infections. Although the precise mechanisms remain unknown, BCG can activate innate immune responses, and an increasing body of evidence demonstrates that the induction of trained innate immunity could explain its non-specific protective effects. IMPLICATIONS: Despite many years of research to prevent and treat TL and malaria, these diseases remain a public health problem in tropical countries. Future studies are required to examine if BCG vaccination could be used as an effective treatment option.

Immobilization of Lipases on Heterofunctional Octyl-Glyoxyl Agarose Supports: Improved Stability and Prevention of the Enzyme Desorption.

Lipases are among the most widely used enzymes in industry. Here, a novel method is described to rationally design the support matrix to retain the enzyme on the support matrix without leaching and also activate the enzyme for full activity retention. Lipases are interesting biocatalysts because they show the so-called interfacial activation, a mechanism of action that has been used to immobilize lipases on hydrophobic supports such as octyl-agarose. Thus, adsorption of lipases on hydrophobic surfaces is very useful for one step purification, immobilization, hyperactivation, and stabilization of most lipases. However, lipase molecules may be released from the support under certain conditions (high temperature, organic solvents), as there are no covalent links between the enzyme and the support matrix. A heterofunctional support has been proposed in this study to overcome this problem, such as the heterofunctional glyoxyl-octyl agarose beads. It couples the numerous advantages of the octyl-agarose support to covalent immobilization and creates the possibility of using the biocatalyst under any experimental conditions without risk of enzyme desorption and leaching. This modified support may be easily prepared from the commercially available octyl-agarose. Preparation of this useful support and enzyme immobilization on it via covalent linking is described here. The conditions are described to increase the possibility of achieving at least one covalent attachment between each enzyme molecule and the support matrix.

Evaluation of anti-nociceptive and anti-inflammatory activity of low-level laser therapy on temporomandibular joint inflammation in rodents.

The aim of this study was to investigate the analgesic and anti-inflammatory activity of low-level laser therapy (LLLT) on the nociceptive behavioral as well as histomorphological aspects induced by injection of formalin and carrageenan into the rat temporomandibular joint. The 2.5% formalin injection (FRG group) induced behavioral responses characterized by rubbing the orofacial region and flinching the head quickly, which were quantified for 45 min. The pretreatment with systemic administration of diclofenac sodium-DFN group (10 mg/kg i.p.) as well as the irradiation with LLLT infrared (LST group, 780 nm, 70 mW, 30 s, 2.1 J, 52.5 J/cm(2), GaAlAs) significantly reduced the formalin-induced nociceptive responses. The 1% carrageenan injection (CRG group) induced inflammatory responses over the time-course of the study (24 h, and 3 and 7 days) characterized by the presence of intense inflammatory infiltrate rich in neutrophils, scanty areas of liquefactive necrosis and intense interstitial edema, extensive hemorrhagic areas, and enlargement of the joint space on the region. The DFN and LST groups showed an intensity of inflammatory response that was significantly lower than in CRG group over the time-course of the study, especially in the LST group, which showed exuberant granulation tissue with intense vascularization, and deposition of newly formed collagen fibers (3 and 7 days). It was concluded that the LLLT presented an anti-nociceptive and anti-inflammatory response on the inflammation induced in the temporomandibular joint of rodents.

Statin effects on regulatory and proinflammatory factors in chronic idiopathic urticaria.

Immunological dysfunction has been described to occur in chronic idiopathic urticaria (CIU), most notably in association with an inflammatory process. Some pharmacological agents as statins--drugs used in hypercholesterolaemia--display a broad effect on the immune response and thus should be tested in vitro in CIU. Our main objectives were to evaluate the effects of statins on the innate and adaptive immune response in CIU. Simvastatin or lovastatin have markedly inhibited the peripheral blood mononuclear cells (PBMC) proliferative response induced by T and B cell mitogens, superantigen or recall antigen. Simvastatin arrested phytohaemaglutinin (PHA)-induced T cells at the G0/G1 phase, inhibiting T helper type 1 (Th1), Th2, interleukin (IL)-10 and IL-17A cytokine secretion in both patients and healthy control groups. Up-regulation of suppressor of cytokine signalling 3 (SOCS3) mRNA expression in PHA-stimulated PBMCs from CIU patients was not modified by simvastatin, in contrast to the enhancing effect in the control group. Statin exhibited a less efficient inhibition effect on cytokine production [IL-6 and macrophage inflammatory protein (MIP)-1α] induced by Toll-like receptor (TLR)-4, to which a statin preincubation step was required. Furthermore, statin did not affect the tumour necrosis factor (TNF)-α secretion by lipopolysaccharide (LPS)-stimulated PBMC or CD14+ cells in CIU patients. In addition, LPS-activated PBMC from CIU patients showed impaired indoleamine 2,3-dioxygenase (IDO) mRNA expression compared to healthy control, which remained at decreased levels with statin treatment. Statins exhibited a marked down-regulatory effect in T cell functions, but were not able to control TLR-4 activation in CIU patients. The unbalanced regulatory SOCS3 and IDO expressions in CIU may contribute to the pathogenesis of the disease.

[Assessment of 3 radiographic methods (conventional periapical, digital periapical, and panoramic) ni the diagnosis of artificially produced periapical lesions]. / Avaliação de três métodos radiográficos (periapical convencional, periapical digital e panorâmico) no diagnóstico de lesões apicais produzidas artificialmente.

This research was carried out in order to evaluate three radiographic methods--conventional periapical, digital periapical and panoramic--in the diagnosis of artificially produced periapical lesions. For this purpose, 5 mandibles, with lesions produced by means of spherical drills of different sizes, were used. The research was divided into five distinct phases, as follows: phase Z (initial)--characterized by the absence of lesion; phase R--lesion produced with a number 6 drill; phase J--lesion produced with a number 8 drill; phase D--lesion produced with a number 10 drill; and phase H--lesion reaching the vestibular cortex. The lesions were produced in quadrants. Radiographs were made after each phase and analyzed by 4 experts in radiology. For the digital system there was statistically significant difference in phase R (in the region of incisors) and in phase H (in the region of premolars). In the region of molars there was statistically significant difference in phase D for panoramic radiography. It must be pointed out that panoramic radiography produced the less effective results in phase H.

Odontoma-producing intraosseous calcifying odontogenic cyst: case report.

The present report describes a case of odontoma-producing intraosseous calcifying odontogenic cyst in a 36-year-old Black male in the right mandibular bicuspid region. The lesion involved an unerupted permanent canine, which was displaced to the mandible base and a calcified mass that was later recognized as an odontoma. The lesion was surgically removed.

The role of mechanical bowel preparation for colonic resection and anastomosis: an experimental study.

BACKGROUND AND AIMS: To evaluate the effect of mechanical bowel preparation (MBP) on colonic resection and anastomosis. PATIENTS AND METHODS: Mongrel dogs were divided into two groups of 20 animals each. During the preoperative period (24 h) group A was not subjected to MBP, and group B was fasted and ingested 20 ml magnesium hydroxide plus 15 ml/kg 10% mannitol orally. All animals underwent segmental colectomy followed by end-to-end anastomosis. The survivors of both groups were reoperated upon on the 7th postoperative day. RESULTS: Mortality before reoperation was significantly higher in group A (45%) than in group B (10%; P<0.05). Upon reoperation on surviving animals the incidence of localized anastomotic leakage, leakage with peritonitis, and healed anastomoses was 72.72%, 9.09%, and 18.8% in group A, and 66.66%, 22.22%, and 11.11% in group B, respectively (P>0.05). Aerobic and anaerobic bacterial cultures showed similar growth in the two groups. CONCLUSION: We conclude that the omission of MBP increased the mortality due to early anastomotic leakage with peritonitis; MBP did not change the rate of localized anastomotic leakage, leakage with peritonitis, or intact anastomoses on the 7th day; no quantitative or qualitative differences were observed in the bacteria isolated from the two groups.

[Kinetic distribution of cyclosporine after single dose subcutaneous administration; experimental study in rats]. / Disposição cinética da ciclosporina após administração de dose única subcutânea; estudo experimental em ratos.

Adequate dose of cyclosporin A shows immunosuppressor effect, and low toxicity. The doses reported previously ranged from 2.5 to 25 mg/kg every 24, 48 hours and even 7 days. Routes for cyclosporin A administration are subcutaneous or intramuscular preferentially. In the present study, cyclosporin A (CSA) single dose subcultaneous was administered to 21 Wistar-Furth rats, adult, males, weighing 350-450g. The animals were divided in 3 groups receiving 2.5 mg/kg (group 1), 5.0 mg/kg (group 2) and 10.0 mg/kg (group 3). Blood samples were collected at 1, 4, 8, 12, 24, 48 and 72 hours after drug collection into plastic tubes containing sodium EDTA. Blood cyclosporin A levels were determined by a commercially available radioimmunoassay kit (Sandoz RIE Kit Basel) after whole hemolysis using liquid nitrogen. Cyclosporin A blood concentrations vs time curve were plotted (log C vs t). Two compartment open model was applied to estimate the kinetic parameters as t(1/2) beta e beta. A model independent calculation was applied to estimate the kinetic parameters as AUCT, CIT and Vd. Initially, parametric and nonparametric tests were applied. Due to the high dispositional variability, nonparametric statistics (Wilcoxon's test) was applied for analysis of results obtained. Based on data obtained in the present study the authors suggest linear pharmacokinetics where Cmax AUCT showed proportional increases with the dose administered, remaining unchanged the Kinetic parameters as t(1/2) B,B, CIT and Vd.

[Lumbar microdiscectomy. Technique and results in 80 cases]. / Microdiscectomia lombar. Técnica e resultados em 80 casos.

The results of treatment for 80 patients with lumbar disc disease who undergone microdiscectomy were reviewed. Low rate of post-operative complications, short hospital stay and early return of the patients to their normal activities were observed.

Increased capacity of the coronary arteries in chronic Chagas' heart disease: further support for the neurogenic pathogenesis concept.

A postmortem study of the capacity of the coronary arteries is presented. The amount of injected Schlessinger's barium-gelatin mass taken up by the coronary arterial tree under standard conditions was used as a measure of coronary capacity. A total of 63 hearts, consisting of those with Chagas' cardiopathy, normal hearts, and hypertrophied hearts, were studied. Correlation coefficients between coronary capacity and heart weight, as well as index of coronary capacity based on heart weight, were the parameters submitted to statistical analysis. Positive correlation coefficients between coronary capacity and heart weight were detected in normal and chagasic cases but not in hypertrophied cases. Multiple comparisons of the indexes showed a highly significant increase of coronary capacity in chagasic cases when compared with normal (p less than 0.005) and hypertrophied hearts (p less than 0.01). The characteristic parasympathetic denervation, resulting in a relative sympathetic overdrive, is suggested to be the basic cause of enlargement of the coronary tree in Chagas' heart disease, thus providing further support for the neurogenic pathogenetic concept.