Skeletal muscle degeneration and regeneration after injection of bothropstoxin-II, a phospholipase A2 isolated from the venom of the snake Bothrops jararacussu

A myotoxic phospholipase A2, named bothropstoxin II (BthTX-II), was isolated from the venom of the South American snake Bothrops jararacussu and the pathogenesis of myonecrosis induced by this toxin was studied in mice. BthTX-II induced a rapid increase in plasma creatine kinase levels. Histological and ultrastructural observations demonstrate that this toxin affects muscle fibers by first disrupting the integrity of plasma membrane, as delta lesions were the earliest morphological alteration and since the plasma membrane was interrupted or absent in many portions. In agreement with this hypothesis, BthTX-II released peroxidase entrapped in negatively charged multilamellar liposomes and behaved as an amphiphilic protein in charge shift electrophoresis, an indication that its mechanism of action might be based on the interaction and disorganization of plasma membrane phospholipids. Membrane damage was followed by a complex series of morphological alterations in intracellular structures, most of which are probably related to an increase in cytosolic calcium levels. Myofilaments became hypercontracted into dense clumps which alternated with cellular spaces devoid of myofibrillar material. Later on, myofilaments changed to a hyaline appearance with a more uniform distribution. Mitochondria were drastically affected, showing high amplitude swelling, vesiculation of cristae, formation of flocculent densities, and membrane disruption. By 24 hr, abundant polymorphonuclear leucocytes and macrophages were observed in the interstitial space as well as inside necrotic fibers. Muscle regeneration proceeded normally, as abundant myotubes and regenerating myofibers were observed 7 days after BthTX-II injection. By 28 days regenerating fibers had a diameter similar to that of adult muscle fibers, although they presented two distinctive features: central location of nuclei and some fiber splitting. This good regenerative response may be explained by the observation that BthTX-II does not affect blood vessels, nerves, or basal laminae. © 1991.

Gold electrodes from recordable CDs for mercury quantification by flow injection analysis

The development of a new methodology for the construction of very efficient flow cells for mercury detection by potentiometric stripping analysis, employing the thin gold layer of recordable CDs as working electrode is reported. This new source of electrodes (CDtrodes) show very attractive performance, similar to that obtained with commercial gold electrodes, with superior versatility. The low cost of this new source of gold electrodes allows a frequent replacement of the electrode, avoiding cumbersome clean-up treatments. Various experimental parameters have been optimized to yield low detection limits (0.25 ng/mL of mercury for 5 min deposition at 0.3 V) and good precision (standard deviation of 1.9% was obtained for 15 repetitive measurements using 10 ng/mL of mercury). Standard curves were found to be linear over the range of 0.5-100 μg L-1 of mercury. The flow cells developed were used for the quantification of mercury in oceanic and tap water. © Springer-Verlag 2000.

Chin augmentation with conchal cartilage

Profile enhancement most frequently involves mentoplasty. For this purpose, the author performs conchal grafts to the chin. A total of 28 women aged 15 to 76 years (mean age, 38.11 ± 15.11 years) requested mentoplasty by itself or combined with rhinoplasty, rhytidoplasty, or submental lipoplasty. The conchal cartilage was harvested subperichondrally through a posterior 3-cm incision. The specimen measured 3 x 1 cm, which was sufficient to project the chin 2 to 3 mm. For 4 to 5 mm of projection, both cartilages were used. The graft was positioned under the periosteum and held with two 5-0 nylon sutures. In these cases, the conchal cartilage graft was a suitable option for chin augmentations up to 5 mm.

A simple high-performance liquid chromatography assay for on-line determination of catecholamines in adrenal gland by direct injection on an ISRP column

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development and validation of a rapid turbidimetric assay to determine the potency of cefuroxime sodium in powder for dissolution for injection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A new heterologous fibrin sealant as a scaffold to cartilage repair - experimental study and preliminary results

Autologous fibrin gel is commonly used as a scaffold for filling defects in articular cartilage. This biomaterial can also be used as a sealant to control small hemorrhages and is especially helpful in situations where tissue reparation capacity is limited. In particular, fibrin can act as a scaffold for various cell types because it can accommodate cell migration, differentiation, and proliferation. Despite knowledge of the advantages of this biomaterial and mastery of the techniques required for its application, the durability of several types of sealant at the site of injury remains questionable. Due to the importance of such data for evaluating the quality and efficiency of fibrin gel formulations on its use as a scaffold, this study sought to analyze the heterologous fibrin sealant developed from the venom of Crotalus durissus terrificus using studies in ovine experimental models. The fibrin gel developed from the venom of this snake was shown to act as a safe, stable, and durable scaffold for up to seven days, without causing adverse side effects. Fibrin gel produced from the venom of the Crotalus durissus terrificus snake possesses many clinical and surgical uses. It presents the potential to be used as a biomaterial to help repair skin lesions or control bleeding, and it may also be used as a scaffold when applied together with various cell types. The intralesional use of the fibrin gel from the venom of this snake may improve surgical and clinical treatments in addition to being inexpensive and adequately consistent, durable, and stable. The new heterologous fibrin sealant is a scaffold candidate to cartilage repair in this study.

Simple and clean determination of tetracyclines by flow injection analysis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Development and validation of a rapid turbidimetric assay to determine the potency of ampicillin sodium in powder for solution for injection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development and validation of an economic, environmental friendly and stability-indicating analytical method for determination of ampicillin sodium for injection by RP-HPLC

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development of an innovative, ecological and stability-indicating analytical method for semiquantitative analysis of ampicillin sodium for injection by thin layer chromatography (TLC)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development and validation of the quantitative analysis of cefuroxime sodium in powder for injection by infrared spectroscopy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development and validation of the quantitative analysis of ceftazidime in powder for injection by infrared spectroscopy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development and validation of the quantitative analysis of ampicillin sodium in powder for injection by Fourier-transform infrared spectroscopy (FT-IR)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Preparation and evaluation of the electrospun chitosan/PEO fibers for potential applications in cartilage tissue engineering

Fibrous materials have morphological similarities to natural cartilage extracellular matrix and have been considered as candidate for bone tissue engineering scaffolds. In this study, we have evaluated a novel electrospun chitosan mat composed of oriented sub-micron fibers for its tensile property and biocompatibility with chondrocytes (cell attachment, proliferation and viability). Scanning electronic microscope images showed the fibers in the electrospun chitosan mats were indeed aligned and there was a slight cross-linking between the parent fibers. The electrospun mats have significantly higher elastic modulus (2.25 MPa) than the cast films (1.19 MPa). Viability of cells on the electrospun mat was 69% of the cells on tissue-culture polystyrene (TCP control) after three days in culture, which was slightly higher than that on the cast films (63% of the TCP control). Cells on the electrospun mat grew slowly the first week but the growth rate increased after that. By day 10, cell number on the electrospun mat was almost 82% that of TCP control, which was higher than that of cast films (56% of TCP). The electrospun chitosan mats have a higher Young’s modulus (P <0.01) than cast films and provide good chondrocyte biocompatibility. The electrospun chitosan mats, thus, have the potential to be further processed into three-dimensional scaffolds for cartilage tissue repair.

The Effectiveness of Psychological Interventions for the Treatment of Erectile Dysfunction: Systematic Review and Meta-Analysis, Including Comparisons to Sildenafil Treatment, Intracavernosal Injection, and Vacuum Devices

In contrast to the impressive advances in somatic research of erectile dysfunction (ED), scientific literature shows contradictory reports on the results of psychotherapy for the treatment of ED. Authors conducted a meta-analysis to evaluate the effectiveness of psychological interventions for the treatment of ED compared to oral drugs, local injection, vacuum devices, or other psychological intervention. Distinct sources of randomized controlled trials (RCTs) were searched: electronic databases (between 1966 and 2007), cross checking of references, and contact with scientific societies. For dichotomous outcomes the pooled relative risks were calculated and for continuous outcomes mean differences between interventions. Statistical heterogeneity was addressed. Eleven RCTs involving 398 men met the inclusion criteria. There is evidence that group therapy improves ED. Focused sex group therapy showed greater efficacy than control group. Men randomized to receive psychotherapy plus sildenafil showed significant improvement of ED and were less likely than those receiving only sildenafil to drop out. Regarding to the effectiveness of psychological interventions for the treatment of ED compared to local injection and vacuum devices no difference was found. Melnik T, Soares BGO, and Nasello AG. The effectiveness of psychological interventions for the treatment of erectile dysfunction: Systematic review and meta-analysis, including comparisons to sildenafil treatment, intracavernosal injection, and vacuum devices. J Sex Med 2008;5:2562-2574.