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Demand for the development of cassava varieties with different native starches has guided the search for these characteristics in the germplasm of Manihot esculenta Crantz. Therefore, the objective of this study was to estimate the genetic diversity of cassava accessions for root and starch granule characteristics to guide the future industrial application of this species. Starches from 56 accessions were evaluated for the number of granules in 1 g of starch (NTG), area (AG, μm), length (LG, μm), width (WG, μm), starch granule roundness (Round), dry matter content in the roots (DMC, %), pulp color (PulCo), and cyanogenic compounds (HCN). Images captured by light microscopy were used to determine the average phenotypic values, and these were further analyzed by principal component analysis (PCA) considering mixed data (quantitative and qualitative). Significant differences between the cassava accessions for all traits measured revealed wide variability in starch granule characteristics. Four diversity groups with better fitness for the classification of cassava accessions based on PulCo were identified, in comparison with HCN. Accessions with differential starch characteristics were identified, and crossings for the generation of segregating populations in order to obtain table and industry varieties have been proposed.

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Our aim was to evaluate genetic polymorphism of molecules involved in immunoregulatory/allergic processes in patients who presented with cutaneous hypersensitivity caused by chemically unrelated nonsteroidal anti-inflammatory drugs. Polymorphisms at IL10 (-1082 G>A), IL4 (-589 C>T), CTLA4 (+49A>G), and DAO (+8956 C>G) genes were studied in 55 cases and 97 controls by the polymerase chain reaction-restriction fragment length polymorphism technique. With regard to the polymorphism at IL10 -1082, higher frequencies of the AG genotype (57% vs 39%) and G allele carriers (70% vs 48%) were found among the patients, indicating a risk effect (odds ratio [OR] = 2.56 and P = .01 for AG genotype and OR = 2.52; P = .01 for AG/GG). For the CTLA4 +49 A/G single-nucleotide polymorphism (SNP), AG genotype (31.0%) (P = .02) and G carrier (54.0%) (P = .05) frequencies were found to be significantly lower in the patient group compared with the control group (51.0% and 69.0%, respectively). The SNP DAO +8956 C>G was associated with a strong protective effect, with OR values of 0.83 for CG and 0.11 for GG genotype (P = .04 for the codominant model), suggesting an allele dose effect. The combination of IL10 and DAO SNPs in a multivariate model did not alter the OR values, suggesting independent effects for both SNPs. The results are striking. In conclusion, these results suggest that polymorphisms in regulatory targets of the immune response and in DAO gene could modulate an individual's susceptibility to nonsteroidal anti-inflammatory drug hypersensitivity reactions. Further studies will be necessary to complement our results.

Tumor necrosis factor α antagonists are proven to be effective for the treatment of chronic inflammatory conditions, such as psoriasis. A major concern for patients is the risk of acquiring granulomatous infectious diseases caused by the immunosuppressive effects of the drugs. We report a 60-year-old man with psoriasis who underwent infliximab treatment for 2 years and developed secondary leprosy, presenting extensive erythematous and infiltrated plaques on the trunk and limbs with loss of sensitivity (thermal, pain and tactile). The skin lesion biopsy showed perivascular epithelioid granulomas, nodular dermal aggregates of foamy macrophages and bundles of acid-fast bacilli. The clinical picture associated with histopathologic evaluation suggested borderline lepromatous leprosy. Before infliximab treatment, the patient had a positive tuberculin skin test and underwent chemoprophylaxis treatment for latent tuberculosis. Although the tuberculin reactivity suggests a strong correlation with a latent Mycobacterium tuberculosis infection, the possibility of infections by other mycobacteria, such as Mycobacterium leprae, should not be discarded.

We evaluated interleukin-10 (IL10) －592 C/A, IL4－589 C/T, interferon gamma (IFNG)＋874 A/T, cytotoxic T-lymphocyte-associated antigen 4 (CTLA4)＋49 A/G gene polymorphisms associated with efavirenz hypersensitivity reaction. A total of 63 human immunodeficiency virus-positive patients under treatment at a public hospital were included in the study, of whom 21 presented with efavirenz hypersensitivity. Patients who presented with efavirenz hypersensitivity reaction showed a higher frequency of the IL10 －592A allele than the controls (p＝0.028). The allele A was associated with increased risk of efavirenz hypersensitivity (odds ratio＝2.40). In case of IL4, a significant difference in the frequency of the IL4 －589 (C/T) polymorphism was not observed between patients and controls. A significant inverse correlation was observed when comparing the CTLA4＋49A/G and IL4 －589 C/T polymorphisms (r＝－0.650, p＝0.001); that is, the CTLA4 +49GG genotype, involved with the lowest capacity of inhibition, was inversely correlated IL4－589TT genotype, which induces high production of IL-4. With respect to the CTLA4＋49A/G and IFNG＋874T/A gene polymorphisms, significant differences in allele and genotype frequencies were not observed between the groups. Therefore, our data suggest that polymorphisms in regulatory regions of cytokine genes could modulate an individual's susceptibility to efavirenz hypersensitivity reaction.

The distribution and frequency of single nucleotide polymorphisms (SNPs) can help to understand changes associated with characteristics of interest. We aimed to evaluate nucleotide diversity in six genes involved in starch biosynthesis in cassava using a panel of 96 unrelated accessions. The genes were sequenced, aligned, and used to obtain values for nucleotide diversity (π), segregating sites (θ), Tajima's D test, and neighbor-joining (NJ) clustering. On average, one SNP per 147 and 171 bp was identified in exon and intron regions, respectively. Thirteen heterozygous loci were found. Three of seven SNPs in the exon region resulted in non-synonymous replacement or four synonymous substitutions. However, no associations were noted between SNPs and root dry-matter content. The parameter π ranged from 0.0001 (granule bound starch synthase I) to 0.0033 (α-amylase), averaging 0.0011, while θ ranged from 0.00014 (starch branching enzyme) to 0.00584 (starch synthase I), averaging 0.002353. The θ diversity value was typically double that of the π. Results of the D test did not suggest any evidence of deviance of neutrality in these genes. Among the evaluated accession, 82/96 were clustered using the NJ method but without a clear separation of the root dry-matter content, root pulp coloration, and classification of the cyanogenic compound content. High variation in genes of the starch biosynthetic pathway can be used to identify associations with the functional properties of starch for the use of polymorphisms for selection purposes.

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