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1.
Ecol Evol ; 14(6): e11555, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38895571

ABSTRACT

Intraspecific variation in plants is expected to have profound impacts on the arthropod communities associated with them. Because sexual dimorphism in plants is expected to provide consistent variation among individuals of the same species, researchers have often studied the effect it has on associated arthropods. Nevertheless, most studies have focused on the effect of sexual dimorphism in a single or a few herbivores, thus overlooking the potential effects on the whole arthropod community. Our main objective was to evaluate effects of Buddleja cordata's plant-sex on its associated arthropod community. We surveyed 13 pairs of male and female plants every 2 months during a year (June 2010 to April 2011). Every sampling date, we measured plant traits (water content and leaf thickness), herbivory, and the arthropod community. We did not find differences in herbivory between plant sex or through time. However, we found differences in water content through time, with leaf water-content matching the environmental seasonality. For arthropod richness, we found 68 morphospecies associated with female and 72 with male plants, from which 53 were shared by both sexes. We did not observe differences in morphospecies richness; however, we found sex-associated differences in the diversity of all species and differences on the diversity of the most abundant species with an interesting temporal component. During peak flowering season, male plants showed higher values on both parameters, but during the peak fructification season female plants showed the higher values on both diversity parameters. Our research exemplifies the interaction between plant-phenology and plant-sex as drivers of arthropod communities' diversity, even when plant sexual-dimorphism is inconspicuous, and highlighting the importance of accounting for seasonal variation. We stress the need of conducting more studies that test this time-dependent framework in other dioecious systems, as it has the potential to reconcile previous contrasting observations reported in the literature.

2.
Tissue Antigens ; 70(5): 442-4, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17868257

ABSTRACT

A novel human leukocyte antigen-DQ allele, DQB1*0622, was identified in a bone marrow transplantation candidate. DQB1*0622 differs from DQB1*0609 by two nucleotide differences in exon 2, position 122 (A-->T) and 177 (A-->G). The difference at position 122 resulted in an amino acid change (Tyrosine to Phenylalanine). However, the difference at position 177 did not cause any amino acid change.


Subject(s)
Alleles , Amino Acid Substitution , Exons , HLA-DQ Antigens/genetics , Mutation, Missense , Base Sequence , HLA-DQ beta-Chains , Humans , Molecular Sequence Data
3.
Tissue Antigens ; 65(2): 192-4, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15713220

ABSTRACT

A novel HLA-B allele, B*3549, was identified in a bone marrow transplantation candidate. B*3549 differs from B*3525 by two nucleotides at exon 2, position 142 (T to G) and 165 (G to C). The difference at position 142 resulted in an amino acid difference (serine to alanine). However, the difference at position 165 did not cause any amino acid change. This novel allele was found on a haplotype with A*3101, B*3549, Cw*0401, DRB1*0407, and DQB1*0302.


Subject(s)
HLA-B Antigens/genetics , Alleles , Base Sequence , Bone Marrow Transplantation , Female , HLA-B Antigens/classification , HLA-DR Antigens/genetics , Histocompatibility Testing , Humans , Male , Molecular Sequence Data , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational , Sequence Homology, Nucleic Acid
4.
Rev Hosp Clin Fac Med Sao Paulo ; 53(6): 311-6, 1998.
Article in Portuguese | MEDLINE | ID: mdl-10413947

ABSTRACT

Two hundred and fifty two blood donors HBsAg positive (mean age = 32.6, 91, 7% male) were searched into a transversal study to determine their clinical, laboratorial and histological characteristics. It was also compared the positiviness and negativiness of the serologic markers HBeAg, anti-Hbe and IgM anti-HBc with the values of serum aminotransferases. Hepatomegaly and splenomegaly were detected in 9.9% (25/252) and in 2.4% (6/252) respectively. In 17.5% (44/251) and 28.3% (71/251) the AST and ALT were respectively, over 50 UI/I. The positive frequencies of the various serologic markers of hepatitis B virus in 120 patients were: anti-HBc total in 89.5% (102/114), HBeAg in 25.7% (28/109) anti-Hbe in 67.3% (66/98), IgM anti-HBc in 40.8% (49/120); anti-Delta in 0.0% (0.66). Thirty one patients were submitted to liver biopsy, due do clinical alteration and/or of the aminotransferases. The hystological findings were: normal liver in 16.1% (5/31), non specific hystological alterations in 22.6% (7/31), persistent chronic hepatitis in 22.6% (7/31), active chronic hepatitis in 6.5% (2/31), cirrhosis in 12.9% (4/31), alcoholic hepatitis in 3.2% (1/31), lobular chronic hepatitis in 3.2% (1/31) and alterations exclusively due to schistosomiasis in 12.9% (4/31). Schistosomiasis elements (granuloma and/or Symmers fibrosis) were also notived in 7 patients. The comparative analysis of positiveness and negativeness of the serologic markers with the aminotransferases ("t" test of Student) showed significative difference of the averages (p < 0.05) only in relation to the simultaneous positeveness and negativeness of the HBeAg and IgM anti-HBc (average of AST = 56.11 and ALT = 78.00 when HBeAg and IgM anti-HBc were positive; average of AST = 24.25 and ALT = 27.00 when HBeAg and IgM anti-HBc were negative). According to this study the conclusion are: 1) The presence of two markers (HBeAg and IgM anti-HBc) and not only one determinant of viral replication in asymptomatic HBsAg carriers can strongly indicate a significant biochemical activity suggestive of hepatocellular lesion. 2) The presence of HBeAg in 25.7% (28/109) clearly shows the high rate of carriers with a potential of infectivity. 3) The results of hepatic histology shows that the majority of our patients had either normal liver or mild histological alterations. It is important to notice that only the cases with elevated aminotransferases were submitted to liver biopsies. The alterations caused by schistosomiasis shows, as is well known, the high prevalence of the parasitism in our surroundings. 4) The clinical aspects of the patients studied did not show significant alterations. Risk factors to get the infection were low. The hematologic and biochemical parameters (except aminotransferases) were either normal or just slightly abnormal. It was not detected a statistically significant difference. 5) The co-infections by delta virus was null.


Subject(s)
Alanine Transaminase/blood , Aspartate Aminotransferases/blood , Blood Donors , Hepatitis B Surface Antigens/blood , Hepatitis B/diagnosis , Adult , Brazil , Cohort Studies , Cross-Sectional Studies , Female , Hepatitis B/immunology , Humans , Immunoglobulin M/blood , Liver/pathology , Male , Middle Aged , Predictive Value of Tests
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