359 research outputs found
Early intestinal perforation secondary to congenital mesenteric defects
Gastrointestinal perforation (GIP) in preterm neonates may be idiopathic, due to necrotizing enterocolitis (NEC), or mechanical obstruction. The predominant cause of GIP in the neonatal period is NEC. Differential diagnosis with congenital malformations, including mesenteric defects leading to internal hernias, is mandatory if the onset is early. We describe two newborns with trans-mesenteric herniation resulting in GIP, and we discuss the presence of possible additional risk factors such as prematurity and predisposing vascular disruption in connective tissue disorders (Ehlers-Danlos syndrome), twinning, and use of assisted reproductive technologies. These cases prompted us to review our exploratory laparotomies performed for intestinal obstruction, complicated/or not with perforation, to identify the frequency of neonatal trans-mesenteric hernias in a referral hospital. The prevalence of GIP and of internal hernia was 25% and 3.3%, respectively. In conclusion, time-onset and particular conditions associated with GIP should lead to a high index of suspicion for internal hernias in order to achieve appropriate diagnosis and therapy
The echocardiography diagnosis of cor pulmonale in a horse
The authors describe the two-dimensional and Doppler signs that characterize the pulmonary hypertension caused by chronic obstructive pulmonary disease (COPD) in a horse
Diagnostic factors for recurrent pregnancy loss: an expanded workup
Purpose: There is limited information on the risk factors for recurrent pregnancy loss (RPL). Methods: In this study, a patient-based approach was used to investigate the possible involvement and relative relevance of a large number of diagnostic factors in 843 women with RPL who underwent an extensive diagnostic workup including 44 diagnostic factors divided into 7 major categories. Results: The rates of abnormalities found were: (1) genital infections: 11.74%; (2) uterine anatomic defects: 23.72%; (3) endocrine disorders: 29.42%; (4) thrombophilias: 62%; (5) autoimmune abnormalities: 39.2%; (6) parental karyotype abnormalities 2.25%; (7) clinical factors: 87.78%. Six hundred and fifty-nine out of eight hundred and forty-three women (78.17%) had more than one abnormality. The mean number of pregnancy losses increased by increasing the number of the abnormalities found (r = 0.86949, P < 0.02). The factors associated with the highest mean number of pregnancy losses were cervical isthmic incompetence, anti-beta-2-glycoprotein-1 antibodies, unicornuate uterus, anti-prothrombin A antibodies, protein C deficiency, and lupus anticoagulant. The majority of the considered abnormalities had similar, non-significant prevalence between women with 2 versus ≥ 3 pregnancy losses with the exception of age ≥ 35 years and MTHFR A1298C heterozygote mutation. No difference was found between women with primary and secondary RPL stratified according to the number of abnormalities detected (Chi-square: 8.55, P = 0.07). In these women, the only factors found to be present with statistically different rates were age ≥ 35 years, cigarette smoking, and genital infection by Ureaplasma. Conclusion: A patient-based diagnostic approach in women with RPL could be clinically useful and could represent a basis for future research
New Histamine-Related Five-Membered N-Heterocycle Derivatives as Carbonic Anhydrase I Activators
A series of histamine (HST)-related compounds were synthesized and tested for their activating properties on five physiologically relevant human Carbonic Anhydrase (hCA) isoforms (I, II, Va, VII and XIII). The imidazole ring of HST was replaced with different 5-membered heterocycles and the length of the aliphatic chain was varied. For the most interesting compounds some modifications on the terminal amino group were also performed. The most sensitive isoform to activation was hCA I (K(A) values in the low micromolar range), but surprisingly none of the new compounds displayed activity on hCA II. Some derivatives (1, 3a and 22) displayed an interesting selectivity for activating hCA I over hCA II, Va, VII and XIII
Optical phonon modes of wurtzite InP
Optical vibration modes of InP nanowires in the wurtzite phase were investigated by Raman scattering spectroscopy. The wires were grown along the [0001] axis by the vapor-liquid-solid method. The A1(TO), E2h, and E1(TO) phonon modes of the wurtzite symmetry were identified by using light linearly polarized along different directions in backscattering configuration. Additionally, forbidden longitudinal optical modes have also been observed. Furthermore, by applying an extended 11-parameter rigid-ion model, the complete dispersion relations of InP in the wurtzite phase have been calculated, showing a good agreement with the Raman experimental data
Role of Prolactin Receptors in Lymphangioleiomyomatosis
Pulmonary lymphangioleiomyomatosis (LAM) is a rare lung disease caused by mutations in the tumor suppressor genes encoding Tuberous Sclerosis Complex (TSC) 1 and TSC2. The protein product of the TSC2 gene is a well-known suppressor of the mTOR pathway. Emerging evidence suggests that the pituitary hormone prolactin (Prl) has both endocrine and paracrine modes of action. Here, we have investigated components of the Prl system in models for LAM. In a TSC2 (+/-) mouse sarcoma cell line, down-regulation of TSC2 using siRNA resulted in increased levels of the Prl receptor. In human LAM cells, the Prl receptor is detectable by immunohistochemistry, and the expression of Prl in these cells stimulates STAT3 and Erk phosphorylation, as well as proliferation. A high affinity Prl receptor antagonist consisting of Prl with four amino acid substitutions reduced phosphorylation of STAT3 and Erk. Antagonist treatment further reduced the proliferative and invasive properties of LAM cells. In histological sections from LAM patients, Prl receptor immuno reactivity was observed. We conclude that the Prl receptor is expressed in LAM, and that loss of TSC2 increases Prl receptor levels. It is proposed that Prl exerts growth-stimulatory effects on LAM cells, and that antagonizing the Prl receptor can block such effects
Oxidative stress signalling in the apoptosis of Jurkat T lymphocytes
The pathways of transduction of oxidative stress signals have been studied using the Jurkat T cell model
The oxidative stress was induced by exposure of the cells to 100 mM H2O2. DNA damage was detected within 15 min
after commencement of treatment. DNA damage repair occurred within about 1 h in cells exposed to oxidative stress for
15 min. In continuous exposure to stress, DNA repair was slower and control levels of DNA integrity were not reached.
DNA repair did not involve gene transcription. H2O2 at 100 mM caused cell death by necrosis as well as by apoptosis.
Both these processes were induced by 15 min exposure to the stress stimulus. However, some important differences
were found between necrosis and apoptosis. Necrosis was more rapid, began within an hour of treatment and continued
to increase during the full duration of the experiment. But apoptosis was seen after 4 h from treatment and was
conspicuous between 6 and 20 h after the start of treatment. The necrotic phase preceded apoptosis, although these did
show an overlap. In the necrotic phase, Bcl-2, Caspase 8 genes were down regulated. The 6\ub120 h phase characterised by
a marked increase in apoptosis is accompanied by the up regulation of both Bcl-2 and Caspase genes. Expression of the
Fas and p53 genes was not altered in either phase. We also analysed the levels of expression of the scavenging genes
whose gene products are involved in detoxi\uaecation. No modulation of the antioxidant enzymes, catalase, Cu/Zn superoxide
dismutase and glutatione peroxidase was detectable
Dipturus trachydermus, Roughskin Skate
The Roughskin Skate (Dipturus trachydermus) is a large skate (to 265 cm total length) that occurs in the Southeast Pacific and Southwest Atlantic from Coquimbo, Chile (31°S), south around Cape Horn and north to RĂo de la Plata, Uruguay, including the Falkland Islands (Malvinas). It is demersal on the outer continental shelf and upper slope at depths of 85–480 m, but is most commonly found at 200–350 m in Chile and shallower (80–150 m) in Argentina. It is captured in industrial trawl fisheries for hake (Merluccius spp.), and artisanal bottom longline fisheries that encompass nearly the entire geographic and depth range of this species in Chile and Argentina. In Chile, it was a secondary catch of the target skate fishery which ramped up in 1993 as a direct result of the arrival of Korean skate traders who provided a market that incentivised fishers to target and retain this species for international trade.Fil: Dulvy, N. K.. University Fraser Simon; CanadáFil: Acuña, E.. Universidad CatĂłlica del Norte; ChileFil: Bustamante, C.. Universidad de Antofagasta; ChileFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". EstaciĂłn HidrobiolĂłgica de Puerto QuequĂ©n (sede QuequĂ©n); ArgentinaFil: Concha, F.. Universidad de ValparaĂso; ChileFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Paesch, L.. DirecciĂłn Nacional de Recursos Acuáticos; UruguayFil: Pompert, J.. No especifĂca;Fil: Rincon, G.. Universidade Federal Do Maranhao.; BrasilFil: Velez Zuazo, X.. Smithsonian Conservation Biology Institute; Estados Unido
Valence-band splitting energies in wurtzite InP nanowires : Photoluminescence spectroscopy and ab initio calculations
We investigated experimentally and theoretically the valence-band structure of wurtzite InP nanowires. The wurtzite phase, which usually is not stable for III-V phosphide compounds, has been observed in InP nanowires. We present results on the electronic properties of these nanowires using the photoluminescence excitation technique. Spectra from an ensemble of nanowires show three clear absorption edges separated by 44 meV and 143 meV, respectively. The band edges are attributed to excitonic absorptions involving three distinct valence-bands labeled: A, B, and C. Theoretical results based on"ab initio" calculation gives corresponding valence-band energy separations of 50 meV and 200 meV, respectively, which are in good agreement with the experimental results
Gene and protein expression in response to different growth temperatures and oxygen availability in Burkholderia thailandensis.
Published onlineJournal ArticleResearch Support, Non-U.S. Gov'tThis is the final version of the article. Available from Public Library of Science via the DOI in this record.Burkholderia thailandensis, although normally avirulent for mammals, can infect macrophages in vitro and has occasionally been reported to cause pneumonia in humans. It is therefore used as a model organism for the human pathogen B. pseudomallei, to which it is closely related phylogenetically. We characterized the B. thailandensis clinical isolate CDC2721121 (BtCDC272) at the genome level and studied its response to environmental cues associated with human host colonization, namely, temperature and oxygen limitation. Effects of the different growth conditions on BtCDC272 were studied through whole genome transcription studies and analysis of proteins associated with the bacterial cell surface. We found that growth at 37°C, compared to 28°C, negatively affected cell motility and flagella production through a mechanism involving regulation of the flagellin-encoding fliC gene at the mRNA stability level. Growth in oxygen-limiting conditions, in contrast, stimulated various processes linked to virulence, such as lipopolysaccharide production and expression of genes encoding protein secretion systems. Consistent with these observations, BtCDC272 grown in oxygen limitation was more resistant to phagocytosis and strongly induced the production of inflammatory cytokines from murine macrophages. Our results suggest that, while temperature sensing is important for regulation of B. thailandensis cell motility, oxygen limitation has a deeper impact on its physiology and constitutes a crucial environmental signal for the production of virulence factors.This work was supported by Fondazione CARIPLO (Progetto Vaccini, contract number 2009–3577) and by Ministero dell’Istruzione, dell’Università e della Ricerca (MIUR) (project FIRB RBLA039LSF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
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