337 research outputs found

    Assessment of hygienic conditions of ground pepper (Piper nigrum L.) on the market in SĂŁo Paulo city, by means of two methodologies for detecting the light filth

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    Pepper should to be collected, processed, and packed under optimum conditions to avoid the presence of foreign matter. The hygienic conditions of ground pepper marketted in São Paulo city were assessed in determining the presence of foreign matter by means of two extraction methodologies. This study was carried out during a six-month time period from May to September 2006. The occurrence of light impurities was determined either by the flotation technique following the methodology recommended by AOAC or by enzyme – linked immunosorbent assay (ELISA). It was observed that 100% of the examined samples contained insect fragments, and many samples were housing more than one type of foreign matter. Twentytwo percent of samples were unqualified for consumption owing to the occurrence of rodent hairs. For the calibration of ELISA test for quantification of insect contamination level in pepper samples, a range of standard-infested samples was prepared in adding 1, 2, 4, 8 and 10 insects in a control sample to estimate the number of insects in the analyzed samples by measuring optical densities (OD) values with a spectrophotometer. Among the 22 samples, 36.4% of samples presented OD values close to that corresponding to the standard infested with eight insects, 40.9% of samples were comparable to OD of the standard infested with four insects, 18.2% comparable to standard with 10 insects, and 4.5% to the standard with two insects. According to the results observed in the present study, the technique described in AOAC official methods manual was found more suitable for detecting not only the insects but also the additional impurities in analyzed samples, while ELISA is specific to detect myosin from the insect muscle, which undergoes serious degradation with time. Keywords: Pepper, ELISA test , Light filth, AOAC official method

    Pretherapeutic gamma-glutamyltransferase is an independent prognostic factor for patients with renal cell carcinoma.

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    BACKGROUND: Gamma-glutamyltransferase (GGT) regulates apoptotic balance and promotes cancer progression and invasion. Higher pretherapeutic GGT serum levels have been associated with worse outcomes in various malignancies, but there are no data for renal cell carcinoma (RCC). METHODS: Pretherapeutic GGT serum levels and clinicopathological parameters were retrospectively evaluated in 921 consecutive RCC patients treated with nephrectomy at a single institution between 1998 and 2013. Gamma-glutamyltransferase was analysed as continuous and categorical variable. Associations with RCC-specific survival were assessed with Cox proportional hazards models. Discrimination was measured with the C-index. Decision-curve analysis was used to evaluate the clinical net benefit. The median postoperative follow-up was 45 months. RESULTS: Median pretherapeutic serum GGT level was 25 U l(-1). Gamma-glutamyltransferase levels increased with advancing T (P<0.001), N (P=0.006) and M stages (P<0.001), higher grades (P<0.001), and presence of tumour necrosis (P<0.001). An increase of GGT by 10 U l(-1) was associated with an increase in the risk of death from RCC by 4% (HR 1.04, P<0.001). Based on recursive partitioning-based survival tree analysis, we defined four prognostic categories of GGT: normal low (<17.5 U l(-1)), normal high (17.5 to <34.5 U l(-1)), elevated (34.5 to <181.5 U l(-1)), and highly elevated (â©Ÿ181.5 U l(-1)). In multivariable analyses that adjusted for the effect of standard features, both continuously and categorically coded GGT were independent prognostic factors. Adding GGT to a model that included standard features increased the discrimination by 0.9% to 1.8% and improved the clinical net benefit. CONCLUSIONS: Pretherapeutic serum GGT is a novel and independent prognostic factor for patients with RCC. Stratifying patients into prognostic subgroups according to GGT may be used for patient counselling, tailoring surveillance, individualised treatment planning, and clinical trial design

    Associations Between Presenting Symptoms, Clinicopathological Parameters, and Prognosis in a Contemporary Series of Patients With Renal Cell Carcinoma

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    PURPOSE: To evaluate the impact of presenting symptoms on survival in a contemporary series of patients with renal cell carcinoma (RCC). MATERIALS AND METHODS: We prospectively recorded data on the presenting symptoms, pathology, and RCC-specific survival of 633 consecutive RCC patients who underwent surgery between 2003 and 2012. RESULTS: Four hundred thirty-three RCCs (68%) were incidental, 111 (18%) were associated with local symptoms, and 89 (14%) were associated with systemic symptoms. Among those with incidental RCC, 317 patients (73%) were completely asymptomatic and 116 patients (27%) presented with symptoms not related to the tumor. During a median follow-up interval of 40 months (interquartile range: 39 to 69 months), 77 patients died from RCC. In univariate analyses, symptom classification was significantly associated with RCC-specific survival (p<0.001). Patients with incidental RCC and unrelated symptoms tended to have worse prognosis than did patients who were completely asymptomatic, although this difference was not statistically significant (p=0.057). The symptom classification was associated with advanced TNM stages (p<0.001) and grade (p<0.001). CONCLUSIONS: This study confirms that presenting symptoms are associated with tumor characteristics and survival. The majority of RCCs are diagnosed incidentally in patients without any symptoms or with symptoms not related to RCC. Patients in the latter group tend to have a worse prognosis than do patients who are completely asymptomatic. With the increasing number of incidentally diagnosed RCCs, substratification of patients with incidental tumors may be prognostically relevant

    Transformação genĂ©tica de cana-de-açĂșcar por Agrobacterium tumefaciens.

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    RESUMO - A utilização das tĂ©cnicas de modificação genĂ©tica de plantas jĂĄ sĂŁo aplicadas comercialmente na agricultura hĂĄ cerca de trĂȘs dĂ©cadas. No entanto, culturas como a cana-de-açĂșcar ainda se beneficiam pouco desta tecnologia. O presente trabalho descreve o processo de transformação genĂ©tica de cana-de-açĂșcar, utilizando como vetor de transformação a Agrobacterium tumefaciens. Dentre as vantagens que se destacam nesse procedimento, podemos citar: simplicidade do procedimento; geração de eventos positivos com menor nĂșmero de cĂłpias do transgene de interesse; e integração do transgene em regiĂ”es mais ativas do genoma, caracterĂ­sticas essas que favorecem o sucesso na obtenção de plantas geneticamente modificadas efetivamente funcionais e estĂĄveis.CIIC 2018. NÂș 17606. Na publicação: Juliana Erika Teixeira Yassitepe

    Structure and mechanism of human DNA polymerase η

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    The variant form of the human syndrome xeroderma pigmentosum (XPV) is caused by a deficiency in DNA polymerase eta (Pol eta), a DNA polymerase that enables replication through ultraviolet-induced pyrimidine dimers. Here we report high-resolution crystal structures of human Pol eta at four consecutive steps during DNA synthesis through cis-syn cyclobutane thymine dimers. Pol eta acts like a 'molecular splint' to stabilize damaged DNA in a normal B-form conformation. An enlarged active site accommodates the thymine dimer with excellent stereochemistry for two-metal ion catalysis. Two residues conserved among Pol eta orthologues form specific hydrogen bonds with the lesion and the incoming nucleotide to assist translesion synthesis. On the basis of the structures, eight Pol eta missense mutations causing XPV can be rationalized as undermining the molecular splint or perturbing the active-site alignment. The structures also provide an insight into the role of Pol eta in replicating through D loop and DNA fragile sites

    Dissection of artifactual and confounding glial signatures by single-cell sequencing of mouse and human brain

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    A key aspect of nearly all single-cell sequencing experiments is dissociation of intact tissues into single-cell suspensions. While many protocols have been optimized for optimal cell yield, they have often overlooked the effects that dissociation can have on ex vivo gene expression. Here, we demonstrate that use of enzymatic dissociation on brain tissue induces an aberrant ex vivo gene expression signature, most prominently in microglia, which is prevalent in published literature and can substantially confound downstream analyses. To address this issue, we present a rigorously validated protocol that preserves both in vivo transcriptional profiles and cell-type diversity and yield across tissue types and species. We also identify a similar signature in postmortem human brain single-nucleus RNA-sequencing datasets, and show that this signature is induced in freshly isolated human tissue by exposure to elevated temperatures ex vivo. Together, our results provide a methodological solution for preventing artifactual gene expression changes during fresh tissue digestion and a reference for future deeper analysis of the potential confounding states present in postmortem human samples

    'Correction:' Serum transforming growth factor beta-1 (TGF-beta-1) levels in diabetic patients are not associated with pre-existent coronary artery disease

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    <p>Abstract</p> <p>Background</p> <p>The association between TGF-ÎČ1 levels and long-term major adverse cardiovascular events (MACE) in patients with coronary artery disease (CAD) is controversial. No study specifically addressed patients with CAD and diabetes mellitus (DM). The association between TGF-ÎČ1 levels and long-term major adverse cardiovascular events (MACE) in patients with coronary artery disease (CAD) is controversial. No study specifically addressed patients with CAD and diabetes mellitus (DM).</p> <p>Methods</p> <p>Patients (n = 135, 30–80 years) referred for coronary angiography were submitted to clinical and laboratory evaluation, and the coronary angiograms were evaluated by two operators blinded to clinical characteristics. CAD was defined as the presence of a 70% stenosis in one major coronary artery, and DM was characterized as a fasting glycemia > 126 mg/dl or known diabetics (personal history of diabetes or previous use of anti-hyperglycemic drugs or insulin). Based on these criteria, study patients were classified into four groups: no DM and no CAD (controls, C n = 61), DM without CAD (D n = 23), CAD without DM (C-CAD n = 28), and CAD with DM (D-CAD n = 23). Baseline differences between the 4 groups were evaluated by the χ<sup>2 </sup>test for trend (categorical variables) and by ANOVA (continuous variables, post-hoc Tukey). Patients were then followed-up during two years for the occurrence of MACE (cardiac death, stroke, myocardial infarction or myocardial revascularization). The association of candidate variables with the occurrence of 2-year MACE was assessed by univariate analysis.</p> <p>Results</p> <p>The mean age was 58.2 ± 0.9 years, and 51% were men. Patients with CAD had a higher mean age (p = 0.011) and a higher percentage were male (p = 0.040). There were no significant baseline differences between the 4 groups regarding hypertension, smoking status, blood pressure levels, lipid levels or inflammatory markers. TGF-ÎČ1 was similar between patients with or without CAD or DM (35.1 ×/Ă· 1.3, 33.6 ×/Ă· 1.6, 33.9 ×/Ă· 1.4 and 31.8 ×/Ă· 1.4 ng/ml in C, D, C-CAD and D-CAD, respectively, p = 0.547). In the 2-year follow-ip, independent predictors of 2-year MACE were age (p = 0.007), C-reactive protein (p = 0.048) and systolic blood pressure (p = 0.008), but not TGF-ÎČ1.</p> <p>Conclusion</p> <p>Serum TGF-ÎČ1 was not associated with CAD or MACE occurrence in patients with or without DM.</p

    Crown Plasticity and Competition for Canopy Space: A New Spatially Implicit Model Parameterized for 250 North American Tree Species

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    BACKGROUND: Canopy structure, which can be defined as the sum of the sizes, shapes and relative placements of the tree crowns in a forest stand, is central to all aspects of forest ecology. But there is no accepted method for deriving canopy structure from the sizes, species and biomechanical properties of the individual trees in a stand. Any such method must capture the fact that trees are highly plastic in their growth, forming tessellating crown shapes that fill all or most of the canopy space. METHODOLOGY/PRINCIPAL FINDINGS: We introduce a new, simple and rapidly-implemented model--the Ideal Tree Distribution, ITD--with tree form (height allometry and crown shape), growth plasticity, and space-filling, at its core. The ITD predicts the canopy status (in or out of canopy), crown depth, and total and exposed crown area of the trees in a stand, given their species, sizes and potential crown shapes. We use maximum likelihood methods, in conjunction with data from over 100,000 trees taken from forests across the coterminous US, to estimate ITD model parameters for 250 North American tree species. With only two free parameters per species--one aggregate parameter to describe crown shape, and one parameter to set the so-called depth bias--the model captures between-species patterns in average canopy status, crown radius, and crown depth, and within-species means of these metrics vs stem diameter. The model also predicts much of the variation in these metrics for a tree of a given species and size, resulting solely from deterministic responses to variation in stand structure. CONCLUSIONS/SIGNIFICANCE: This new model, with parameters for US tree species, opens up new possibilities for understanding and modeling forest dynamics at local and regional scales, and may provide a new way to interpret remote sensing data of forest canopies, including LIDAR and aerial photography
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