Evaluation of Cadaveric Renal Vein Lengths and Their Extension Loss with Three Types of Ligature and Section

Background and Purpose: The right kidney has been less frequently used in live donor nephrectomy, because of the shorter length of the right renal vein (RRV) that is associated with technical difficulties and higher rates of venous thrombosis. In live open donor or deceased donor transplant nephrectomy, an additional cuff of the inferior vena cava is usually removed, but this is a more difficult and risky maneuver in laparoscopic nephrectomy. For this reason, laparoscopic right nephrectomy (LRN) for renal transplantation (RT) is not frequently performed in most medical institutions. We evaluate the difference between RRV and left renal vein (LRV) lengths in cadavers, as harvested for RT by three clamping methods. Our objective was to obtain information that could clarify when LRN for RT should be encouraged or avoided with regard to conventional surgery. Materials and Methods: Ninety adult fresh unfrozen cadavers were randomly divided into three groups of 30, according to the clamping device used: Satinsky, stapler, and Hem-o-lok clip. The abdominal viscera were removed through a median xyphopubic incision, and the veins were measured on the bench. Two lateral limits were used: The renal hilum and the tangential line of the renal poles. As for medial limits, the inferior vena cava or the laparoscopic clipping device on the RRV were used on the right side, while on the LRV, the medial border of the emergence of the adrenal vein was considered. After section of the renal vein, a slight traction of the extremity was applied for the measurement. All measurements were obtained three times using a metallic millimetric ruler, and the arithmetic mean was considered. The chi-square, one-way analysis of variance, and paired t tests were used for statistical analysis. Statistical significance was accepted at P <= 0.05. Results: The groups of cadavers were homogeneous in demographic characteristics. Regardless of the clamping method and considering the useful length of the LRV, the RRV was statistically smaller. The evaluation of the vein length did not depend on the lateral limit considered. Independent of the clamping method, on both sides, the lengths after the vein section were larger than before the section, a fact attributed to traction. Use of a stapler and a single Hem-o-lok presented the same waste of vein length on the right side. On average, the RRV was 13.7% shorter than the LRV. Conclusions: With the wide acceptance of laparoscopic live donor nephrectomy, the length difference between the veins of both kidneys is an important issue, and the right kidney is therefore used less than the left, compared with conventional surgery. This article represents the first step to quantify the anatomic length of renal veins in different situations. Certainly, more imagenologic or surgical studies should be carried out before decisions can be made for better selection of patients for LRN.

An empirical evaluation of imputation accuracy for association statistics reveals increased type-I error rates in genome-wide associations

Background: Genome wide association studies (GWAS) are becoming the approach of choice to identify genetic determinants of complex phenotypes and common diseases. The astonishing amount of generated data and the use of distinct genotyping platforms with variable genomic coverage are still analytical challenges. Imputation algorithms combine directly genotyped markers information with haplotypic structure for the population of interest for the inference of a badly genotyped or missing marker and are considered a near zero cost approach to allow the comparison and combination of data generated in different studies. Several reports stated that imputed markers have an overall acceptable accuracy but no published report has performed a pair wise comparison of imputed and empiric association statistics of a complete set of GWAS markers. Results: In this report we identified a total of 73 imputed markers that yielded a nominally statistically significant association at P < 10(-5) for type 2 Diabetes Mellitus and compared them with results obtained based on empirical allelic frequencies. Interestingly, despite their overall high correlation, association statistics based on imputed frequencies were discordant in 35 of the 73 (47%) associated markers, considerably inflating the type I error rate of imputed markers. We comprehensively tested several quality thresholds, the haplotypic structure underlying imputed markers and the use of flanking markers as predictors of inaccurate association statistics derived from imputed markers. Conclusions: Our results suggest that association statistics from imputed markers showing specific MAF (Minor Allele Frequencies) range, located in weak linkage disequilibrium blocks or strongly deviating from local patterns of association are prone to have inflated false positive association signals. The present study highlights the potential of imputation procedures and proposes simple procedures for selecting the best imputed markers for follow-up genotyping studies.

Hypotheses, rationale, design, and methods for prognostic evaluation in type 2 diabetic patients with angiographically normal coronary arteries. The MASS IV-DM Trial

Background: The MASS IV-DM Trial is a large project from a single institution, the Heart Institute (InCor), University of Sao Paulo Medical School, Brazil to study ventricular function and coronary arteries in patients with type 2 diabetes mellitus. Methods/Design: The study will enroll 600 patients with type 2 diabetes who have angiographically normal ventricular function and coronary arteries. The goal of the MASS IV-DM Trial is to achieve a long-term evaluation of the development of coronary atherosclerosis by using angiograms and coronary-artery calcium scan by electron-beam computed tomography at baseline and after 5 years of follow-up. In addition, the incidence of major cardiovascular events, the dysfunction of various organs involved in this disease, particularly microalbuminuria and renal function, will be analyzed through clinical evaluation. In addition, an effort will be made to investigate in depth the presence of major cardiovascular risk factors, especially the biochemical profile, metabolic syndrome inflammatory activity, oxidative stress, endothelial function, prothrombotic factors, and profibrinolytic and platelet activity. An evaluation will be made of the polymorphism as a determinant of disease and its possible role in the genesis of micro- and macrovascular damage. Discussion: The MASS IV-DM trial is designed to include diabetic patients with clinically suspected myocardial ischemia in whom conventional angiography shows angiographically normal coronary arteries. The result of extensive investigation including angiographic follow-up by several methods, vascular reactivity, pro-thrombotic mechanisms, genetic and biochemical studies may facilitate the understanding of so-called micro- and macrovascular disease of DM.

Evaluation of muscle strength and motor abilities in children with type II and III spinal muscle atrophy treated with valproic acid

Background: Spinal muscular atrophy (SMA) is an autosomal recessive disorder that affects the motoneurons of the spinal anterior horn, resulting in hypotonia and muscle weakness. The disease is caused by deletion or mutation in the telomeric copy of SMN gene (SMN1) and clinical severity is in part determined by the copy number of the centromeric copy of the SMN gene (SMN2). The SMN2 mRNA lacks exon 7, resulting in a production of lower amounts of the full-length SMN protein. Knowledge of the molecular mechanism of diseases has led to the discovery of drugs capable of increasing SMN protein level through activation of SMN2 gene. One of these drugs is the valproic acid (VPA), a histone deacetylase inhibitor. Methods: Twenty-two patients with type II and III SMA, aged between 2 and 18 years, were treated with VPA and were evaluated five times during a one-year period using the Manual Muscle Test (Medical Research Council scale-MRC), the Hammersmith Functional Motor Scale (HFMS), and the Barthel Index. Results: After 12 months of therapy, the patients did not gain muscle strength. The group of children with SMA type II presented a significant gain in HFMS scores during the treatment. This improvement was not observed in the group of type III patients. The analysis of the HFMS scores during the treatment period in the groups of patients younger and older than 6 years of age did not show any significant result. There was an improvement of the daily activities at the end of the VPA treatment period. Conclusion: Treatment of SMA patients with VPA may be a potential alternative to alleviate the progression of the disease.

Prognostic evaluation of early rheumatoid arthritis

The progression of rheumatoid arthritis (RA) is quite variable, ranging from very mild or subclinical forms (approx. 10%) to rapidly progressing and debilitating forms (10-15%). The majority of patients present with an intermediate stage with episodes of exacerbation separated by periods of relative inactivity, which evolves to progressive functional losses. To optimise the therapeutic management of early RA it is necessary to perform periodic evaluations of the clinical and laboratory test responses to the treatment instituted, as well as the parameters indicating disease prognosis. Composite measures are frequently used to evaluate the disease activity score (DAS), including the response criteria of the American College of Rheumatology (ACR), the response criteria and the DAS according to the European League Against Rheumatism (EULAR) and the composite indices of disease activity (CIDsA): DAS, the index of disease activity based on 28 joints (DAS 28), the simplified disease activity index (SDAI) and the clinical disease activity index (CDAI). The evaluation of prognosis includes investigation of the absence or occurrence of disease and joint damage remission. Due to the multifaceted nature of RA, no single clinical or laboratory parameter is able to describe satisfactorily the level of inflammatory activity or the disease prognosis at any given time.

Evaluation of Primary Resistance to HIV Entry Inhibitors Among Brazilian Patients Failing Reverse Transcriptase/Protease Inhibitors Treatment Reveal High Prevalence of Maraviroc Resistance-Related Mutations

Entry inhibitor is a new class of drugs that target the viral envelope protein. This region is variable; hence resistance to these drugs may be present before treatment. The aim of this study was to analyze the frequency of patients failing treatment with transcriptase reverse and protease inhibitors that would respond to the entry inhibitors Enfuvirtide, Maraviroc, and BMS-806. The study included 100 HIV-1 positive patients from one outpatient clinic in the city of Sao Paulo, for whom a genotype test was requested due to treatment failure. Proviral DNA was amplified and sequenced for regions of gp120 and gp41. A total of 80 could be sequenced and from those, 73 (91.3%), 5 (6.3%) and 2 (2.5%) were classified as subtype B, F, and recombinants (B/F and B/C), respectively. CXCR4 co-receptor use was predicted in 30% of the strains. Primary resistance to Enfuvirtide was found in 1.3%, following the AIDS Society consensus list, and 10% would be considered resistant if a broader criterion was used. Resistance to BMS-806 was higher; 6 (7.5%), and was associated to non-B strains. Strikingly, 27.5% of samples harbored one or more mutation among A316T, I323V, and S405A, which have been related to decreased susceptibility of Maraviroc; 15% of them among viruses predictive to be R5. A more common mutation was A316T, which was associated to the Brazilian B strain harboring the GWGR motif at the tip of V3 loop and their derivative sequences. These results may be impact guidelines for genotype testing and treatment in Brazil.

Evaluation of Dendritic Cell-Tumor Cell Hybrid Vaccine Storage

Clinical trials using dendritic cells (DCs) to treat cancer patients have generated promising results in recent years. However, even simple aspects of this therapy are still not well understood, including the storage and distribution of manufactured vaccines. These processes are essential and must be elucidated in order to reduce costs. We evaluated the effects of different storage conditions on vaccine functionality using mixed lymphocyte reaction (MLR). Vaccine storage at 4 degrees C for up to 72 h had no significant effect on vaccine activity. Shipping to distant places is possible, if vaccines are kept at 4 degrees C and used up to 3 days after manufacture date.

Balance control in hemiparetic stroke patients: Main tools for evaluation

Balance problems in hemiparetic patients after stroke can be caused by different impairments in the physiological systems involved in Postural control, including sensory afferents, movement strategies, biomechanical constraints, cognitive processing, and perception of verticality. Balance impairments and disabilities must be appropriately addressed. This article reviews the most common balance abnormalities in hemiparetic patients with stroke and the main tools used to diagnose them.

Evaluation of gastrointestinal motility in awake rats: a learning exercise for undergraduate biomedical students

Souza MA, Souza MH, Palheta RC Jr, Cruz PR, Medeiros BA, Rola FH, Magalhaes PJ, Troncon LE, Santos AA. Evaluation of gastrointestinal motility in awake rats: a learning exercise for undergraduate biomedical students. Adv Physiol Educ 33: 343-348, 2009; doi: 10.1152/advan.90176.2008.-Current medical curricula devote scarce time for practical activities on digestive physiology, despite frequent misconceptions about dyspepsia and dysmotility phenomena. Thus, we designed a hands-on activity followed by a small-group discussion on gut motility. Male awake rats were randomly submitted to insulin, control, or hypertonic protocols. Insulin and control rats were gavage fed with 5% glucose solution, whereas hypertonic-fed rats were gavage fed with 50% glucose solution. Insulin treatment was performed 30 min before a meal. All meals (1.5 ml) contained an equal mass of phenol red dye. After 10, 15, or 20 min of meal gavage, rats were euthanized. Each subset consisted of six to eight rats. Dye recovery in the stomach and proximal, middle, and distal small intestine was measured by spectrophotometry, a safe and reliable method that can be performed by minimally trained students. In a separate group of rats, we used the same protocols except that the test meal contained (99m)Tc as a marker. Compared with control, the hypertonic meal delayed gastric emptying and gastrointestinal transit, whereas insulinic hypoglycemia accelerated them. The session helped engage our undergraduate students in observing and analyzing gut motor behavior. In conclusion, the fractional dye retention test can be used as a teaching tool to strengthen the understanding of basic physiopathological features of gastrointestinal motility.

A score system for quality evaluation of RNA sequence tags: an improvement for gene expression profiling

Background: High-throughput molecular approaches for gene expression profiling, such as Serial Analysis of Gene Expression (SAGE), Massively Parallel Signature Sequencing (MPSS) or Sequencing-by-Synthesis (SBS) represent powerful techniques that provide global transcription profiles of different cell types through sequencing of short fragments of transcripts, denominated sequence tags. These techniques have improved our understanding about the relationships between these expression profiles and cellular phenotypes. Despite this, more reliable datasets are still necessary. In this work, we present a web-based tool named S3T: Score System for Sequence Tags, to index sequenced tags in accordance with their reliability. This is made through a series of evaluations based on a defined rule set. S3T allows the identification/selection of tags, considered more reliable for further gene expression analysis. Results: This methodology was applied to a public SAGE dataset. In order to compare data before and after filtering, a hierarchical clustering analysis was performed in samples from the same type of tissue, in distinct biological conditions, using these two datasets. Our results provide evidences suggesting that it is possible to find more congruous clusters after using S3T scoring system. Conclusion: These results substantiate the proposed application to generate more reliable data. This is a significant contribution for determination of global gene expression profiles. The library analysis with S3T is freely available at http://gdm.fmrp.usp.br/s3t/.S3T source code and datasets can also be downloaded from the aforementioned website.

Experimental Infection of the Opossum Didelphis aurita by Rickettsia felis, Rickettsia bellii, and Rickettsia parkeri and Evaluation of the Transmission of the Infection to Ticks Amblyomma cajennense and Amblyomma dubitatum

This work evaluated the infection of opossums (Didelphis aurita) by Rickettsia felis, Rickettsia bellii, and Rickettsia parkeri and their role as amplifier hosts for horizontal transmission to Amblyomma cajennense and/or Amblyomma dubitatum ticks. Infection in D. aurita was induced by intraperitoneal inoculation with R. felis (n = 4 opossums), R. bellii (n = 4), and R. parkeri (n = 2). Another group of six opossums were inoculated intraperitoneally with Leibovitz-15 sterile culture medium, representing the uninfected groups (n = 2 opossums simultaneously to each infected group). Opossum blood samples collected during the study were used for DNA extraction, followed by real-time polymerase chain reaction targeting the rickettsial gene gltA, hematology, and detection of Rickettsia spp.-reactive antibodies by indirect immunofluorescence assay. Opossums were infested with uninfected A. cajennense and/or A. dubitatum for 30 days postinoculation (DPI). Flat ticks molted from ticks fed on opossums were allowed to feed on uninfected rabbits, which were tested for seroconversion by immunofluorescence assay. Samples of flat ticks were also tested by real-time polymerase chain reaction. Inoculated opossums showed no clinical abnormalities. Antibodies to Rickettsia spp. were first detected at the second to fourth DPI, with detectable titers until the 150th DPI. Rickettsemia was detected only in one opossum inoculated with R. parkeri, at the eighth DPI. Only one A. cajennense tick (2.0%) previously fed on a R. parkeri-inoculated opossum became infected. None of the rabbits infested with opossum-derived ticks seroconverted. The study demonstrated that R. felis, R. bellii, and R. parkeri were capable to produce antibody response in opossums, however, with undetectable rickettsemia for R. felis and R. bellii, and very low rickettsemia for R. parkeri. Further studies must be done with different strains of these rickettsiae, most importantly the strains that have never gone through in vitro passages.

Experimental Infection of Opossums Didelphis aurita by Rickettsia rickettsii and Evaluation of the Transmission of the Infection to Ticks Amblyomma cajennense

The present study evaluated the infection of opossums (Didelphis aurita) by Rickettsia rickettsii and their role as amplifier hosts for horizontal transmission of R. rickettsii to Amblyomma cajennense ticks. Three groups of opossums were evaluated: on day 0, group 1 (G1) was inoculated intraperitoneally with R. rickettsii; group 2 (G2) was infested by R. rickettsii-infected ticks; and group 3 (G3) was the uninfected control group. Opossum rectal temperature was measured daily. Blood samples were collected every 2 to 4 days during 30 days, and used to (1) inoculate guinea pigs intraperitoneally; (2) extract DNA followed by real-time polymerase chain reaction (PCR) targeting the rickettsial gene gltA; (3) study hematology; (4) detect R. rickettsii-reactive antibodies by indirect direct immunofluorescence assay (IFA). Blood was also collected every 10 days from days 30 to 180, to be tested by serology. Opossums were infested by uninfected A. cajennense larvae and nymphs from days 3 to 15. Engorged ticks were collected and allowed to molt in an incubator. Thereafter, the subsequent flat ticks were allowed to feed on uninfected rabbits, which were tested for seroconversion by IFA. Samples of flat ticks were also tested by real-time PCR. All G1 and G2 opossums became infected by R. rickettsii, as demonstrated by real-time PCR or/and guinea pig inoculation, but they showed no clinical abnormality. Rickettsemia was first detected at days 2 to 8, lasting intermittently till days 1 to 30. Approximately 18% and 5% of the flat ticks previously fed on G1 and G2 opossums, respectively, became infected by R. rickettsii, but only the rabbits infested with G1-derived ticks seroconverted. The study demonstrated that R. rickettsii was capable of infecting opossums without causing illness and developing rickettsemia capable of causing infection in guinea pigs and ticks, although the infection rate in ticks was low.

Evaluation of Laser Phototherapy in the Inflammatory Process of the Rat's TMJ Induced by Carrageenan

Aim: The aim of this study was to evaluate, by light microscopy, the effects of laser phototherapy (LPT) at 780nm or a combination of 660 and 790 nm, on the inflammatory process of the rat temporomandibular joint (TMJ) induced by carrageen. Background: Temporomandibular disorders (TMDs) are frequent in the population and generally present an inflammatory component. Previous studies have evidenced positive effects of laser phototherapy on TMDs. However, its mechanism of action on the inflammation of the TMJ is not known yet. Materials and Methods: Eighty-five Wistar rats were divided into 9 groups: G1, Saline; G2, Saline + LPT IR; G3, Saline + LPT IR + R; G4, Carrageenan; G5, Carrageenan + LPT IR; G6, Carrageenan + LPT IR + R; G7, previous LPT + Carrageenan; G8, previous LPT + carrageenan + LPT IR; and G9, previous LPT + carrageenan + LPT IR + R, and then subdivided in subgroups of 3 and 7 days. After animal death, specimens were taken, routinely cut and stained with HE, Sirius Red, and Toluidine Blue. Descriptive analysis of components of the TMJ was done. The synovial cell layers were counted. Results: Injection of saline did not produced inflammatory reaction and the irradiated groups did not present differences compared to non-irradiated ones. After carrageenan injection, intense inflammatory infiltration and synovial cell layers proliferation were observed. The infrared irradiated group presented less inflammation and less synovial cell layers number compared to other groups. Previous laser irradiation did not improve the results. Conclusion: It was concluded that the LPT presented positive effects on inflammatory infiltration reduction and accelerated the inflammation process, mainly with IR laser irradiation. The number of synovial cell layers was reduced on irradiated group.

Evaluation of the Bond Strength Between a Composite Resin and Enamel Submitted to Bleaching Treatment and Etched with Er:YAG Laser

Background: The use of laser irradiation for dental surface treatment may increase tooth-composite bond strength. Its use on bleached teeth may decrease the waiting time between bleaching and restorative procedures. Objective: This study aimed to evaluate the bond strength between a composite resin and bovine enamel bleached with 35% hydrogen peroxide and etched with Er:YAG laser. Materials and Methods: Thirty bovine teeth were randomly divided into six groups (n = 5): G1, unbleached and restored 24 h after storage in artificial saliva, etching with 35% phosphoric acid (PA) (control); G2, unbleached and restored 24 h after storage in artificial saliva, etching with Er:YAG laser and 35% PA; G3, bleached and restored immediately afterward, etching with 35% PA; G4, bleached and restored 24 h after bleaching, etching with 35% PA; G5, bleached and restored immediately afterward, etching with Er:YAG and 35% PA laser; G6, bleached and restored 24 h after bleaching, etching with Er:YAG laser and 35% PA. Bond strength was quantitatively evaluated by microtensile test (1.0 mm/min). Data were submitted to statistical analysis using ANOVA and Tukey tests (alpha - 0.05). Results: Bond strength values (MPa) were G1, 26.17 +/- 4.44; G2, 28.87 +/- 3.94; G3, 17.25 +/- 4.58; G4, 21.93 +/- 5.02; G5, 16.69 +/- 2.31; and G6, 29.06 +/- 8.31. There was no statistically significant difference among groups G1, G2, and G6 (p - 0.119), which presented higher bond strength than group G4, followed by groups G3 and G5. Conclusion: Er:YAG irradiation of bleached surfaces may favor bonding procedures when performed 24 h after bleaching.

In Vitro Evaluation of Enamel Erosion After Nd:YAG Laser Irradiation and Fluoride Application

Objective: Previous investigations have demonstrated improved enamel demineralization resistance after laser irradiation. Due to the possibility of a synergistic effect between laser and fluoride, this study investigated the effect of fluoridated agents and Nd:YAG irradiation separately and in combination on enamel resistance to erosion. Methods: One hundred bovine enamel blocks were randomly divided into 10 groups: G1, untreated (control); G2, acidic phosphate fluoride (APF) (1.23% F) for 4 min; G3, fluoride varnish for 6 h (NaF, 2.26%); G4, 0.5 W Nd: YAG laser (250 mm pulse width, 10 Hz, 35 J/cm(2), with uniform velocity for 30 sec in each application); G5, 0.75 W Nd:YAG laser (52.5 J/cm(2)); G6, 1.0 W Nd:YAG laser (70 J/cm(2)); G7, APF + 0.75 W Nd:YAG laser; G8, 0.75 W Nd:YAG laser + APF; G9, fluoride varnish + 0.75 W Nd:YAG laser; and G10, 0.75 W Nd:YAG laser + fluoride varnish. During 10 d the erosive cycle was conducted by immersion of the blocks in Sprite light for 1 min, followed by immersion in artificial saliva for 59 min. This procedure was consecutively repeated four times per day. In each day, during the remaining 20 h, the blocks were maintained in artificial saliva. The wear was evaluated by profilometry (days 5 and 10). Data were tested by two-way ANOVA and Bonferroni's tests (p < 0.05). Results: The mean wear at days 5 and 10 was, respectively: G1, 1.83 and 2.67 mu m; G2, 1.04 and 2.60 mu m; G3, 1.03 and 2.48 mu m; G4, 1.13 and 2.47 mu m; G5, 1.07 and 2.44 mu m; G6, 1.0 and 2.35 mu m; G7, 0.75 and 2.27 mu m; G8, 0.80 and 2.12 mu m; G9, 0.76 and 2.47 mu m; and G10, 1.09 and 2.46 mu m. At day 5, all the experimental groups presented significant lesser wear when compared to control group. However, at 10 d, only G7 and G8 were still different from control. Conclusions: The association between APF application and laser irradiation seems to be an alternative preventive measure against dental erosion.