2,650 research outputs found
Ex vitro acclimatization of plantain plantlets micropropagated in temporary immersion bioreactor
Plantain (Musa ABB CEMSA 3/4) plantlets were micropropagated in temporary immersion bioreactors (TIB) or in
gelled medium (GM). After ex vitro transfer ROS accumulation was determined by infiltrating leaves with nitroblue
tetrazolium (NBT) and 3,3’-diaminobenzidine (DAB). Stomatal cells were more stained with NBT and DAB in GM
plants than in TIB plants, but the difference disappeared at the end of acclimatization. At the end of the in vitro phase,
GM plantlets showed higher activities of ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR),
monodehydroascorbate reductase (MDHAR) and glutathione reductase (GR), while activities of catalase (CAT),
superoxide dismutase (SOD) and glutathione transferase (GT) were higher in TIB grown plantlets. At the end of
acclimatization GT, SOD, CAT and MDHAR stabilized at low values of activity in plantlets derived from both
treatments. Concerning the correspondent genes, GM plantlets showed higher expression of all transcripts with the
exception of CuZnSOD. The immunobloting of peroxiredoxins (PRXs) showed that chloroplast-located PRXs were
expressed at higher levels in TIB plantlets, some showing polymerization. In conclusion, TIB grown plantlets had an
improved anti-oxidative response when compared with GM
Successful management of bilateral orbital metastases from invasive lobular breast cancer with abemaciclib and letrozole: a case report and literature review
Breast cancer is a significant global health concern, contributing to substantial
morbidity and mortality among women. Hormone receptor-positive (HR+)/HER2-
negative (HER2-) breast cancer constitutes a considerable proportion of cases, and
significant advancements have been made in its management. CDK4/6 inhibitors
(CDK4/6is) are a new targeted therapy that has demonstrated efficacy in adjuvant,
advanced and metastatic settings. The propensity of lobular breast carcinomas for
estrogen-rich sites, such as periocular tissues and orbital fat, may explain their
tendency for orbital metastases. Current treatment strategies for these cases are
predominantly palliative, and the prognosis remains poor. This article presents a
unique case of a 51-year-old female with progressive right periorbital edema, pain,
and limited ocular motility. An imaging work-up showed bilateral intra and
extraconal orbital infiltration, which was biopsied. The histopathologic analysis
disclosed mild chronic inflammatory infiltrate with thickened fibrous tissue and
moderately differentiated lobular carcinoma cells, positive for GATA3 and CK7
markers, with 100% of tumor nuclei expressing estrogen receptors (ER+). A
systemic evaluation showed a multicentric nodular formation in both breasts.
Further diagnostic assessments unveiled an HR+/HER2- bilateral lobular breast
carcinoma with synchronous bilateral orbital metastases. Systemic treatment was
initiated with abemaciclib 150mg twice daily and letrozole 2.5mg once a day.
However, this regimen was interrupted due to toxicity. After two weeks, treatment
was resumed with a reduced abemaciclib dose (100mg twice daily) alongside
letrozole, with a reasonable tolerance. Nearly two years after the initial diagnosis of
inoperable metastatic cancer, the patient remains on the same systemic treatment
regimen with no signs of invasive disease. This case report is the first of a patientpresenting with bilateral orbital metastases from bilateral lobular breast cancer,
showing an impressive and sustained response to a first-line treatment regimen
combining abemaciclib and letrozole. A literature review on bilateral orbital
metastases from breast cancer is also presented.info:eu-repo/semantics/publishedVersio
Comparison of plantain plantlets propagated in temporary immersion bioreactors and gelled medium during in vitro growth and acclimatization
The current work compared the physiological characteristics of plantain (Musa AAB) plantlets micropropagated in
temporary immersion bioreactors (TIB) and on a gelled medium (GM). The plantlets were evaluated during in vitro
growth (in the shoot elongation phase) and at the end of ex vitro acclimatization. TIB improved rooting and gave rise to
longer shoots and higher dry mass. Respiration rate was the highest at the beginning of shoot elongation in both the TIB
and GM plantlets. Photosynthetic rate in TIB was significantly higher than in GM from the midpoint of acclimatization,
whereas a pyruvate kinase (PK) activity was lower. Starch accumulation was ca. two fold higher in corms than in leaves
and always higher in the TIB than GM plantlets. The higher expression of genes coding for carbon metabolism enzymes
PK and phosphoenolpyruvate carboxylase (PEPC) in TIB than in PM indicates a more important role of an autotrophic
metabolism in the TIB plantlets when compared to the GM ones. The accumulated reserves were used during the first
days of acclimatization leading to the higher survival rates and to the better plant quality of the TIB plantlet
A retrospective analysis of clinicopathological and prognostic characteristics of ovarian tumors in the State of Espírito Santo, Brazil
<p>Abstract</p> <p>Background</p> <p>Ovarian cancer is sixth most common cancer among women and the leading cause of death in women with gynecological malignancies. Despite the great impact ovarian cancer has on women's health and its great impact in public economy, Brazil still lacks valuable information concerning epidemiological aspects of this disease</p> <p>Methods</p> <p>We've compiled clinical data of all ovarian tumors registered at the two public hospitals of reference (1997 - 2007), such as: patients' age at diagnosis, tumor histological type, tumor stage, chemotherapy regimens, chemotherapy responsiveness, disease-free survival, and overall survival.</p> <p>Results</p> <p>Women's mean age at diagnosis was 54.67 ± 13.84 for ovarian cancer, 46.15 ± 11.15 for borderline tumors, and 42.01 ± 15.06 for adenomas. Among epithelial ovarian cancer cases, 30.1% were of serous, 13.7% were of mucinous, and 13.7% were of endometrioid type; exceptionally serous carcinoma was diagnosed in women younger than 30 years old. Endometrioid cancer had lower disease-free survival than others (p < 0.05). Cases were predominantly diagnosed as poor prognosis disease (FIGO III and IV, 56.2%). Regarding responsiveness to platinum-based therapy, 17.1% of patients were resistant, whereas 24.6%, susceptible. From these, we found equally responsiveness to platinum alone or its association with paclitaxel or cyclophosphamide.</p> <p>Discussion</p> <p>Our data agreed with other studies regarding mean patients' age at diagnosis, histological type frequency, FIGO stages distribution, and chemotherapy regimens. However, the histological type distribution, with equal contribution of mucinous and endometrioid types seems to be a unique characteristic of the studied highly miscegenated population.</p> <p>Conclusion</p> <p>We have enlighten the profile of the studied ovarian cancer population, which might enable the development of more efficient political strategies to control this malignancy that is the fifth leading cause of cancer-related deaths among women.</p
The Custodial Randall-Sundrum Model: From Precision Tests to Higgs Physics
We reexamine the Randall-Sundrum (RS) model with enlarged gauge symmetry
SU(2)_L x SU(2)_R x U(1)_X x P_LR in the presence of a brane-localized Higgs
sector. In contrast to the existing literature, we perform the Kaluza-Klein
(KK) decomposition within the mass basis, which avoids the truncation of the KK
towers. Expanding the low-energy spectrum as well as the gauge couplings in
powers of the Higgs vacuum expectation value, we obtain analytic formulas which
allow for a deep understanding of the model-specific protection mechanisms of
the T parameter and the left-handed Z-boson couplings. In particular, in the
latter case we explain which contributions escape protection and identify them
with the irreducible sources of P_LR symmetry breaking. We furthermore show
explicitly that no protection mechanism is present in the charged-current
sector confirming existing model-independent findings. The main focus of the
phenomenological part of our work is a detailed discussion of Higgs-boson
couplings and their impact on physics at the CERN Large Hadron Collider. For
the first time, a complete one-loop calculation of all relevant Higgs-boson
production and decay channels is presented, incorporating the effects stemming
from the extended electroweak gauge-boson and fermion sectors.Comment: 74 pages, 13 figures, 3 tables. v2: Matches version published in JHE
PEEP-ZEEP technique: cardiorespiratory repercussions in mechanically ventilated patients submitted to a coronary artery bypass graft surgery
<p>Abstract</p> <p>Background</p> <p>The PEEP-ZEEP technique is previously described as a lung inflation through a positive pressure enhancement at the end of expiration (PEEP), followed by rapid lung deflation with an abrupt reduction in the PEEP to 0 cmH<sub>2</sub>O (ZEEP), associated to a manual bilateral thoracic compression.</p> <p>Aim</p> <p>To analyze PEEP-ZEEP technique's repercussions on the cardio-respiratory system in immediate postoperative artery graft bypass patients.</p> <p>Methods</p> <p>15 patients submitted to a coronary artery bypass graft surgery (CABG) were enrolled prospectively, before, 10 minutes and 30 minutes after the technique. Patients were curarized, intubated, and mechanically ventilated. To perform PEEP-ZEEP technique, saline solution was instilled into their orotracheal tube than the patient was reconnected to the ventilator. Afterwards, the PEEP was increased to 15 cmH<sub>2</sub>O throughout 5 ventilatory cycles and than the PEEP was rapidly reduced to 0 cmH<sub>2</sub>O along with manual bilateral thoracic compression. At the end of the procedure, tracheal suction was accomplished.</p> <p>Results</p> <p>The inspiratory peak and plateau pressures increased during the procedure (p < 0.001) compared with other pressures during the assessment periods; however, they were within lung safe limits. The expiratory flow before the procedure were 33 ± 7.87 L/min, increasing significantly during the procedure to 60 ± 6.54 L/min (p < 0.001), diminishing to 35 ± 8.17 L/min at 10 minutes and to 36 ± 8.48 L/min at 30 minutes. Hemodynamic and oxygenation variables were not altered.</p> <p>Conclusion</p> <p>The PEEP-ZEEP technique seems to be safe, without alterations on hemodynamic variables, produces elevated expiratory flow and seems to be an alternative technique for the removal of bronchial secretions in patients submitted to a CABG.</p
Changes in calcium dynamics following the reversal of the sodium-calcium exchanger have a key role in AMPA receptor-mediated neurodegeneration via calpain activation in hippocampal neurons
Proteolytic cleavage of the Na(+)/Ca(2+) exchanger (NCX) by calpains impairs calcium homeostasis, leading to a delayed calcium overload and excitotoxic cell death. However, it is not known whether reversal of the exchanger contributes to activate calpains and trigger neuronal death. We investigated the role of the reversal of the NCX in Ca(2+) dynamics, calpain activation and cell viability, in alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor-stimulated hippocampal neurons. Selective overactivation of AMPA receptors caused the reversal of the NCX, which accounted for approximately 30% of the rise in intracellular free calcium concentration ([Ca(2+)](i)). The NCX reverse-mode inhibitor, 2-[2-[4-(4-nitrobenzyloxy)phenyl]ethyl]isothiourea (KB-R7943), partially inhibited the initial increase in [Ca(2+)](i), and prevented a delayed increase in [Ca(2+)](i). In parallel, overactivation of AMPA receptors strongly activated calpains and led to the proteolysis of NCX3. KB-R7943 prevented calpain activation, cleavage of NCX3 and was neuroprotective. Silencing of NCX3 reduced Ca(2+) uptake, calpain activation and was neuroprotective. Our data show for the first time that NCX reversal is an early event following AMPA receptor stimulation and is linked to the activation of calpains. Since calpain activation subsequently inactivates NCX, causing a secondary Ca(2+) entry, NCX may be viewed as a new suicide substrate operating in a Ca(2+)-dependent loop that triggers cell death and as a target for neuroprotectio
Selectivity of Pesticides used in Integrated Apple Production to the Lacewing, Chrysoperla externa
This research aimed to assess the toxicity of the pesticides abamectin 18 CE (0.02 g a.i. L-1), carbaryl 480 SC (1.73 g a.i. L-1), sulfur 800 GrDA (4.8 g a.i. L-1), fenitrothion 500 CE (0.75 g a.i. L-1), methidathion 400 CE (0.4 g a.i. L-1), and trichlorfon 500 SC (1.5 g a.i. L-1) as applied in integrated apple production in Brazil on the survival, oviposition capacity, and egg viability of the lacewing, Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) from Bento Gonçalves and Vacaria, Rio Grande do Sul State, Brazil. An attempt was made to study morphological changes caused by some of these chemicals, by means of ultrastructural analysis, using a scanning electronic microscope. Carbaryl, fenitrothion, and methidathion caused 100% adult mortality for both populations, avoiding evaluation of pesticides' effects on predator reproductive parameters. Abamectin and sulfur also affected the survival of these individuals with mortality rates of 10% and 6.7%, respectively, for adults from Bento Gonçalves, and were harmless to those from Vacaria at the end of evaluation. Trichlorfon was also harmless to adults from both populations. No compound reduced oviposition capacity. C. externa from Vacaria presented higher reproductive potential than those from Bento Gonçalves. In relation to egg viability, sulfur was the most damaging compound to both populations of C. externa. Ultrastructural analyses showed morphological changes in the micropyle and the chorion of eggs laid by C. externa treated with either abamectin or sulfur. The treatment may have influenced the fertilization of C. externa eggs and embryonic development. Sulfur was responsible for malformations in the end region of the abdomen and genitals of treated females. When applied to adults, abamectin, sulfur, and trichlorfon were harmless, while carbaryl, fenitrothion, and methidathion were harmful, according to the IOBC classification
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