5 research outputs found
Paracoccidioidomicosis, consideraciones de una micosis desatendida
El presente trabajo corresponde a una revisión bibliográfica sobre el estado del
conocimiento de las especies de Paracoccidioides spp. y los cuadros clínicos asociados a este
hongo. La revisión inicia con un marco histórico sobre el desarrollo del conocimiento de la
paracoccidioidomicosis a nivel latinoamericano, incluyendo un apartado sobre Costa Rica.
Se detallan temas relacionados a la etiología, ecología, aspectos veterinarios y la
epidemiología de la micosis.
Adicionalmente, se incluyen temas como la patogenicidad y los factores de virulencia
de Paracoccidioides spp, así como la respuesta inmune que se desarrolla en el hospedero.
Por último, y no menos importante, se describe lo encontrado en la literatura sobre los tópicos
de diagnóstico diferencial, diagnóstico de laboratorio, el tratamiento contra la enfermedad, y
las conclusiones del presente trabajo.
Este trabajo pretende recopilar el conocimiento básico sobre esta micosis y los
últimos avances científicos reportados en la literatura en el tema de la paracoccidiodomicosis
y su agente etiológico.In this document, a literature review of the state of scientific knowledge about
Paracoccidioides spp. species and their associated clinical manifestations was made. This
review starts with a historical frame about knowledge development about
paracoccidioidomycosis in Latin America, including Costa Rica. Etiology, ecology,
veterinary aspects, and this mycosis epidemiology are reviewed.
Additionally, pathogenicity and virulence factors of the causing agent,
Paracoccidioides spp., are included, as well as the host immune response to the fungus.
Finally, topics such as differential diagnosis, laboratory diagnosis and the disease treatment
are discussed, and the concluding remarks of this literature review are detailed.
This work tries to summarize basic knowledge about this mycosis and the latest
scientific advances reported in literature about paracoccidioidomycisis and its etiological
agent.UCR::Vicerrectoría de Investigación::Sistema de Estudios de Posgrado::Salud::Especialidad en Micología Médic
Comparative genomics and transcriptomics elucidate virulence mechanisms and host responses in infectious diseases
The main thematic area of the present thesis is the development and application of bioinformatics pipelines, namely whole-genome sequence (WGS) analysis and transcriptome profile analysis. These pipelines were applied to study the fungal pathogen Aspergillus fumigatus (Manuscripts I, III, and IV) and the early human immune mechanisms activated in response to different types of pathogens (bacteria, fungi, and co-infections) in sepsis patients (Manuscript II). The comparative genomic and transcriptomic analyses applied in my thesis have significantly improved our understanding of fungal pathogenicity as well as the pathogen-specific immune response mechanisms of the human host. Next to a number of novel insights, my work included in this thesis has generated a large number of new hypotheses based on big-data analysis, offering the scientific community the possibility to design exciting new research to confirm them in future experimental studies and bring us closer to actual precision medicine for infectious diseases
Molecular basis of C4 protein deficiency in Aboriginal Australians, and a molecular C4 allotyping technique
Since the initial discovery of the association between C4 protein
deficiency and autoimmune disease, much effort has been devoted to
the characterisation of C4 protein and its molecular composition
(Dawkins et al., 1983). From the outset, researchers have found the
C4 protein difficult to work with as it is unstable and degrades
rapidly. However, with the advent of molecular techniques, studies of
the C4 gene have accelerated, uncovering a very complicated and
large duplicated gene region.
This thesis reviews the literature on complement component C4, and
reports on three interrelated research areas involving protein and
DNA analysis of complement C4. Contributions to the molecular
characterisation of the C4 complement gene region and population
genetics are discussed in relation to current knowledge, and direction
for further research is provided.
This study set out to establish whether indigenous people of PNG and
Aboriginal Australians have shared a common gene pool. By
analysing the distribution of polymorphic C4 alleles these studies
found the Aboriginal Australian and PNG populations to be distinctly
different. Analysis of the distribution of C4 alleles in the two ethnic
groups indicated that the two Aboriginal populations showed
significant similarities but the three geographically distinct PNG
populations were significantly different. Studies here suggested these
ethnic populations are more reliably distinguished from each other
by differences in the frequencies of the most frequently occurring
C4 alleles, than by the incidence of rare alleles.
The high frequency of C4 null alleles in northern located Darwin
Aboriginal's reported by Ranford et al. (1987), is not an isolated
incident as this study also found the highest frequencies of C4 null
alleles in northern located Aboriginal Australian's compared to any
ethnic group studied. This could be associated with the high
occurrence of the autoimmune disease Systemic Lupus
Erythematosus (SLE) in Aboriginal Australians, and strong susceptibility of Aboriginal Australians to this disease (Anstey et al.,
1993).
Accurate identification of C4 alleles including C4 null alleles is
essential both for investigating gene-linked disease associations, as
well as for advancing future population genetics studies. Studies here
demonstrate that C4 protein allotyping does not accurately identify
the C4 genotype of an individual. This was highlighted by the lack of
Hardy-Weinberg equilibrium with respect to C4 allele frequencies of
the East Cape York Aboriginal population as well as the identification
of a number of alleles by molecular analysis which could not be
identified by protein typing. The difficulties associated with
determining C4 allotypes by C4 protein gel electrophoresis include
instability of the C4 protein, high degree of technical expertise for
interpretation of allotypes, and limitations of this technique in
distinguishing overlapping alleles.
It was established in these studies that the polymorphic C4d region
of C4 genes may be used by molecular means to identify and type
C4 alleles. With the advent of molecular biological techniques such
as protein and DNA sequencing, and RFLP analysis of the C4 gene
region, information required for development of a molecular-based
typing protocol has become available. Some of the previously
described C4A and C4B alleles have been found to have unique
combinations of polymorphic amino acid residues distributed within
a short stretch of DNA, otherwise known as the C4d region. This
region of the gene is highly polymorphic encoding amino acid
residues known to be involved in immune-complex binding, and also
encodes antigenic determinants. Therefore the C4d region was
considered an ideal candidate for the development of a molecularbased
allotyping protocol. The molecular-based C4 typing technique
developed here is based on PCR-RFLP analysis of the C4d region.
Protein and DNA sequence information, C4 protein allotyping data,
and computer analysis which estimates the predicted isoelectric
value of a protein were used to develop this protocol. Application of
the molecular C4 typing protocol enabled the identification of C4
alleles which co-migrate by C4 protein gel electrophoresis as well as
a number of rare and novel C4 alleles. The molecular basis of C4 null alleles has been extensively studied
in Caucasians, however, very little is known about the genetic basis
of C4 null alleles in other ethnic populations. C4 null alleles from
Aboriginal Australians were investigated here in order to identify
the genetic basis of these alleles compared to those in Caucasians.
Many Caucasian C4 null alleles result from large deletions. However,
this study found that the C4B null allele in Aboriginal Australians
results from either duplication of C4A genes on a single haplotype,
or possession of a hybrid C4A/C4B type of novel allele, which was
denoted as C4A *CAN1. These findings have considerable
significance in relation to the high frequency of C4 null alleles found
in Aboriginal Australian populations. Many of these "null alleles" may
indeed be functional alleles which have been misinterpreted by C 4
protein typing. The molecular basis of C4A null alleles remains
unresolved, however, this study indicates that the defect is likely to
be due to post-transcriptional processing of the allele.
This thesis describes a detailed investigation into the molecular basis
of C4 alleles including rare and null alleles. This information
together with the vast amount of molecular data available on C 4
enabled the development of a molecular-based C4 typing protocol.
This protocol is considered to be a more reliable and accurate typing
method than the traditional protein typing method, and can be easily
adopted in any laboratory for routine allotyping
Skin Diseases and Sexually Transmitted Infections
ПОСОБИЯКОЖНЫЕ БОЛЕЗНИДЕРМАТОЛОГИЯВЕНЕРОЛОГИЯИНОСТРАННЫЕ СТУДЕНТЫВЕНЕРИЧЕСКИЕ БОЛЕЗНИПособие охватывает как общие, так и редкие вопросы дерматологии и венерологии. Содержатся главы о кожных и венерических заболеваниях, которые являются общими для Азии, Африки и Латинской Америки