A001-02 DNA content, chromatin texture and nuclear morphology
in benzo[a]pyrene-transformed human breast epithelial cells after
microcell-mediated transfer of chromosomes 11 and 17
Mello MLS*, Vidal BC, Lareef MH, Hu YF, Yang X, Russo J
Since abnormal chromosomes 11 and 17 have been associated with neoplastic
progression in benzo[a]pyrene-transformed MCF-10F cells, image analysis
was used to assess the effect of inserting normal chromosomes 11 and
17 into MCF-10F tumorigenic cells (BP1-E) by microcell-mediated chromosome
transfer assay. A tendency of DNA amount distribution and nuclear
size restoration to values typical of non-transformed MCF-10F cells
was found especially after the transfer of normal chromosome 17. However,
data on chromatin texture indicate that a more complex genome balance
is required for the nuclear chromatin to recover its normal supraorganization
and expression.
Cytometry 52 – Accepted on December 2002.
*E-mail: mlsmello@unicamp.brBehaviour
*E-mail: pso@unicamp.br
A004-02 Image analysis of dichroism in silver-impregnated
collagen fibers
Vidal BC*
Microscopy & Analysis – Accepted on November 2002
*E-mail: vidal@unicamp.br
A005-02 Collagen fibers in human prostatic lesions:
histochemistry and anisotropies
Taboga SR, Vidal BC*
Journal of Submicroscopic Cytology and Pathology 35 – Accepted
on July 2002
*E-mail: vidal@unicamp.br, taboga@bio.ibilce.unesp.br
A006-02 Experimentally induced heat and cold shock
tolerance in adult Panstrongylus megistus (Burmeister)
Garcia SL, Garcia NL, Oliveira LR, Rodrigues VLCC, Mello MLS*
Thermal shock tolerance in domestic male and female adults in comparison
to that previously reported for nymphs was studied in P. megistus.
The mechanisms that play a role in the cellular protection of this
species under sequential temperature shocks were found to loose effectiveness
with insect development. When tolerance differed with sex, females
showed greater values than males.
Brazilian Journal of Biology 63 - Accepted on January 2002
*E-mail: mlsmello@unicamp.br
A007-02 Reversal of denervation-induced insulin
resistance by SHIP2 protein synthesis blockade
Bertelli DF, Ueno M, Amaral ME, Toyama MH, Carneiro EM, Marangoni
S, Carvalho CR, Saad MJ, Velloso LA, Boschero AC*
Short-term muscle denervation is a reproducible model of tissue specific
insulin resistance. To investigate the molecular basis of insulin
resistance in denervated muscle the downstream signaling molecules
of the insulin-signaling pathway were examined in intact and denervated
soleus muscle of rats. Short-term denervation induced a significant
fall in glucose clearance rates as detected by euglycemic-hyperinsulinemic
clamp, and was associated with significant decrease in insulin-stimulated
tyrosine phosphorylation of IR, IRS1 and IRS2 and serine phosphorylation
of Akt. Moreover, denervation reduced insulin-induced association
between IRS1/IRS2 and p85/PI3-kinase. Denervation caused an increase
in IRS1 and IRS2 associated PI3-kinase activity, but the contents
of phosphorylated phosphoinositides detected by HPLC were significantly
reduced in lipid fractions. No major differences in SHIP2 expression
were detected between intact and denervated muscle. However, serine
phosphorylation of p85/PI3-kinase was reduced in denervated muscle,
while the blockade of SHIP2 expression by antisense oligonucleotide
treatment led to partial restoration of phosphorylated phosphoinositide
contents and to improved glucose uptake. Thus, modulation of the functional
status of SHIP2 may be a major mechanism of insulin resistance induced
by denervation.
American Journal of Physiology and Endocrinol Metabolism
*E-mail: boschero@unicamp.br
A002-02 Interactions between ants, fruits, and seeds
in a restinga forest in southeastern Brazil
Passos L, Oliveira PS*
The interactions between ants and non-myrmecochorous diaspores were
surveyed in a restinga forest (sandy soil) on the coast of south-eastern
Brazil. During 2 y of monthly samplings, 562 interactions involving
48 ant species and 44 species of diaspore were recorded. Ant-diaspore
associations involved a considerable part of the ground-dwelling ant
community. Large ponerine ants individually removed the diaspores
up to 13 m, whereas small ants (myrmicines) normally recruited workers
and consumed the diaspore on the spot. Ant-derived benefits to diaspores
of non-myrmecochorous plants included secondary dispersal (small to
medium-sized diaspores), and increased germination success after seed
cleaning by ants. Seedlings of three species were associated with
nests of O. chelifer. The results indicate that ants play an important
role in fruit/seed biology in the restinga forest.
Journal of Tropical Ecology
*E-mail: pso@unicamp.br
A003-02 Maternal care in the Neotropical harvestman
Bourguyia albiornata (Arachnida: Opiliones): oviposition site selection
and egg protection
Machado G, Oliveira PS*
Females of the harvestman Bourguyia albiornata oviposit almost exclusively
inside the tube formed by the curled leaves of the bromeliad Aechmea
nudicaulis. Oviposition is not correlated with rainfall or with temperature,
but is negatively correlated with the number of individuals of A.
nudicaulis emitting flowers. During one year, 83.6% of the females
produced only one egg-batch and the remaining produced two or three
batches. The mean number of eggs per batch along successive reproductive
events decreased significantly. Ants were the most important egg predators
group, and at the study site at least 20 species nest and/or forage
in A. nudicaulis. Intense predation on eggs by generalist predators
may be an important pressure promoting parental care in Neotropical
harvestmen.
A008-02 Cytogenetics of a new species of the Paratelmatobius
cardosoi group (Anura: Leptodactylidae) with the description of an
apparent case of pericentric inversion
Lourenço LB, Garcia PC, Recco-Pimentel SM*
Amphibia-Reptilia
*E-mail: shirlei@unicamp.br
A009-02 Chromosomal differentiation of Hyla nana
and Hyla sanborni (Anura, Hylidae), with a description of NOR polymorphism
in H. nana
Medeiros LR, Rossa-Feres DC, Recco-Pimentel SM*
Journal of Heredity
*E-mail: shirlei@unicamp.br
