8 research outputs found
Recurrence of cervical intraepithelial lesions after thermo-coagulation in HIV-positive and HIV-negative Nigerian women
Genome-wide DNA methylation analysis on C-reactive protein among Ghanaians suggests molecular links to the emerging risk of cardiovascular diseases
Heat shock, with recovery, promotes protection of Nicotiana tabacum during subsequent exposure to Ralstonia solanacearum
The Family Acholeplasmataceae (Including Phytoplasmas)The Prokaryotes
The family Acholeplasmataceae was originally established to
accommodate the genus Acholeplasma, comprising the mollicutes that
could be cultivated without the supplement of cholesterol and that
use UGA as a stop codon instead of coding for tryptophan. It was
later shown that the phytoplasmas, a large group of uncultivable,
wall-less, non-helical mollicutes that are associated with plants and
insects, shared taxonomically relevant properties with members of the
genus Acholeplasma. Being not cultivable in vitro in axenic culture, the
phytoplasmas could not be classified using the standards used for other
mollicutes and are named using the category of Candidatus, as “Ca.
Phytoplasma.”
Although phytoplasmas are associated with habitats and ecology
different from acholeplasmas, the two genera Acholeplasma and
“Candidatus Phytoplasma” are phylogenetically related and form a
distinct clade within the Mollicutes. The persisting inability to grow
the phytoplasmas in vitro hinders the identification of their distinctive
phenotypic traits, important criteria for mollicute classification. Until
supplemental phenotypic traits become available, the genus “Candidatus
Phytoplasma” is designated, on the basis of phylogeny, as a tentative
member in the family Acholeplasmataceae. Phylogenetic analysis based
on gene sequences, in particular, ribosomal sequences, has provided
the major supporting evidence for the composition and taxonomic
subdivision of this group of organisms with diverse habitats and ecology
and has become the mainstream for the Acholeplasmataceae systematics.
However, without the ability to determine phenotypic properties, the
circumscription of related species among the non culturable members of
the family remains a major issue.
The genus Acholeplasma comprises 14 species predominantly associated
with animals and isolated from mammalian fluids but regarded as not
normally pathogenic. Conversely, the genus “Ca. Phytoplasma” includes
plant pathogens of major economic relevance worldwide. To date, 36
“Ca. Phytoplasma species” have been described
Cervical cancer prevention and treatment research in Africa: a systematic review from a public health perspective
Guidelines for the use and interpretation of assays for monitoring autophagy
In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued
to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been
expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have
described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable
methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a
difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or
autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete
process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result
in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within,
lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is
especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily
equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a
concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity.
Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine
macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are
focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part
on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most
appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we
consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by
discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field