bluuebunny/crossref_metadata_2025_split huggingface dataset:
TNK2 preserves epidermal growth factor receptor expression on the cell surface and enhances migration and invasion of human breast cancer cells
Authors: Howlin Jillian , Rosenkvist Jeanette , Andersson Tommy 
Published: April 2008

Abstract
Introduction
Amplification of the TNK2 gene in primary tumours correlates with poor prognosis. In accordance, TNK2 overexpression was shown to promote invasion of cancer cells – but the mechanism by which TNK2 mediates these effects is unresolved. TNK2 was suggested to regulate Cdc42-driven migration by activation of breast cancer antioestrogen resistance 1 (BCAR1); however, distinct from this effect is evidence for a role of TNK2 in the regulation of epidermal growth factor receptor (EGFR) endocytosis and degradation. In the present study we sought to investigate whether negative targeting of TNK2 by siRNA could be used to inhibit cancer cell invasion, to establish the contribution of its effect on the EGFR and to consequently attempt to resolve the issue of TNK2's mechanism of action.

Methods
We used siRNA to knockdown expression of TNK2 and its proposed effector BCAR1 in order to analyse the effect of this knockdown on cancer cell behaviour in vitro. We examined morphological changes using phase-contrast microscopy and immunohistochemistry. Functional parameters examined included apoptosis, proliferation, migration and invasion. We also performed flow cytometry analysis to examine EGFR cell surface expression and carried out western blot to examine the total EGFR levels.

Results
We observed that targeting of TNK2 by siRNA in breast cancer cells resulted in distinct morphological changes characterised by a stellate appearance and an absence of protrusions at membrane edges. These changes were not recapitulated upon siRNA targeting of BCAR1. We thus hypothesised that a component of the effects induced by TNK2 may be independent of BCAR1. Consistent with the idea of an alternative mechanism for TNK2, we observed that TNK2 associates with activated EGFR in breast cancer cells in a TNK2-kinase-independent manner. Furthermore, we demonstrated that TNK2 functions to maintain EGFRs on the cell surface. We could demonstrate that the main functional effect of activating these surface EGFRs in breast cancer cells is stimulation of migration. In accordance, TNK2 silencing by siRNA led to a significant reduction in cell surface EGFR and to a concomitant decrease in the migratory and invasive capacity of breast cancer cells.

Conclusion
Our data suggest that TNK2 can enhance migration and invasion of breast cancer cells via preservation of EGFR expression, notwithstanding its previously reported signalling via BCAR1, explaining its oncogenic behaviour in vitro and correlation with metastatic human breast cancer in vivo.
Effect of a heated humidifier during continuous positive airway pressure delivered by a helmet
Authors: Chiumello Davide , Chierichetti Monica , Tallarini Federica , Cozzi Paola , Cressoni Massimo , Polli Federico , Colombo Riccardo , Castelli Antonio , Gattinoni Luciano 
Published: April 2008

Abstract
Introduction
The helmet may be an effective interface for the delivery of noninvasive positive pressure ventilation. The high internal gas volume of the helmet can act as a 'mixing chamber', in which the humidity of the patient's expired alveolar gases increases the humidity of the dry medical gases, thus avoiding the need for active humidification. We evaluated the temperature and humidity of respiratory gases inside the helmet, with and without a heated humidifier, during continuous positive airway pressure (CPAP) delivered with a helmet.

Methods
Nine patients with acute respiratory failure (arterial oxygen tension/fractional inspired oxygen ratio 209 ± 52 mmHg) and 10 healthy individuals were subjected to CPAP. The CPAP was delivered either through a mechanical ventilator or by continuous low (40 l/min) or high flow (80 l/min). Humidity was measured inside the helmet using a capacitive hygrometer. The level of patient comfort was evaluated using a continuous scale.

Results
In patients with acute respiratory failure, the heated humidifier significantly increased the absolute humidity from 18.4 ± 5.5 mgH2O/l to 34.1 ± 2.8 mgH2O/l during ventilator CPAP, from 11.4 ± 4.8 mgH2O/l to 33.9 ± 1.9 mgH2O/l during continuous low-flow CPAP, and from 6.4 ± 1.8 mgH2O/l to 24.2 ± 5.4 mgH2O/l during continuous high-flow CPAP. Without the heated humidifier, the absolute humidity was significantly higher with ventilator CPAP than with continuous low-flow and high-flow CPAP. The level of comfort was similar for all the three modes of ventilation and with or without the heated humidifier. The findings in healthy individuals were similar to those in the patients with acute respiratory failure.

Conclusion
The fresh gas flowing through the helmet with continuous flow CPAP systems limited the possibility to increase the humidity. We suggest that a heated humidifier should be employed with continuous flow CPAP systems.
Widespread duplications in the genomes of laboratory stocks of Dictyostelium discoideum
Authors: Bloomfield Gareth , Tanaka Yoshimasa , Skelton Jason , Ivens Alasdair , Kay Robert R 
Published: April 2008

Abstract
Background
Duplications of stretches of the genome are an important source of individual genetic variation, but their unrecognized presence in laboratory organisms would be a confounding variable for genetic analysis.

Results
We report here that duplications of 15 kb or more are common in the genome of the social amoeba Dictyostelium discoideum. Most stocks of the axenic 'workhorse' strains Ax2 and Ax3/4 obtained from different laboratories can be expected to carry different duplications. The auxotrophic strains DH1 and JH10 also bear previously unreported duplications. Strain Ax3/4 is known to carry a large duplication on chromosome 2 and this structure shows evidence of continuing instability; we find a further variable duplication on chromosome 5. These duplications are lacking in Ax2, which has instead a small duplication on chromosome 1. Stocks of the type isolate NC4 are similarly variable, though we have identified some approximating the assumed ancestral genotype. More recent wild-type isolates are almost without large duplications, but we can identify small deletions or regions of high divergence, possibly reflecting responses to local selective pressures. Duplications are scattered through most of the genome, and can be stable enough to reconstruct genealogies spanning decades of the history of the NC4 lineage. The expression level of many duplicated genes is increased with dosage, but for others it appears that some form of dosage compensation occurs.

Conclusion
The genetic variation described here must underlie some of the phenotypic variation observed between strains from different laboratories. We suggest courses of action to alleviate the problem.
Microscopic wire guide-based orotracheal mouse intubation: description, evaluation and comparison with transillumination
Authors: Hamacher J , Arras M , Bootz F , Weiss M , Schramm R , Moehrlen U 
Published: April 2008

Summary Airway access is needed for a number of experimental animal models, and the majority of animal research is based on mouse models. Anatomical conditions in mice are small, and the narrow glottic opening allows intubation only with a subtle technique. We therefore developed a microscopic endotracheal intubation method with a wire guide technique in mice anaesthetized with halothane in oxygen. The mouse is hung perpendicularly with its incisors on a thread fixed on a vertical plate. The tongue is placed with a pair of forceps between the left hand's thumb and forefinger and slightly pulled, while the neck and thorax are positioned using the third and fourth fingers. By doing so, the neck can be slightly stretched, which allows optimal visualization of the larynx and the vocal cords. To ensure a safe intubation, a fine wire guide is placed under vision between the vocal cords and advanced about 5 mm into the trachea. An intravenous 22G × 1 in. plastic or Teflon catheter is guided over this wire. In a series of 41 mice, between 21 and 38 g, the success rate for the first intubation attempt was >95%. Certainty of the judgement procedure was 100% and success rate was higher using the described method when compared with a transillumination method in a further series. The technique is safe, less invasive than tracheostomy and suitable for controlled ventilation and pulmonary substance application.
Electroencephalography in the diagnosis of hydrocephalus in golden hamsters (Mesocricetus auratus)
Authors: Bali M S , Gebhardt-Henrich S , Keller P , Steiger A , Gattermann R , Bergamasco L , Kronen P , Doherr M G , Botteron C , Tomek A , Jaggy A 
Published: April 2008

Summary The golden hamster ( Mesocricetus auratus) is a popular laboratory animal and is used in a multitude of behavioural studies. However, it has been shown that it suffers from different forms of hereditary hydrocephalus, which may result in behavioural changes. This prospective study was designed to look into the usefulness of electroencephalography (EEG) measurements in the diagnosis of hydrocephalus in hamsters. The EEGs of the hydrocephalic hamsters were evaluated double-blind and showed a high-voltage slow wave activity, with a fast activity superimposed onto it. This pattern has already been well described in other hydrocephalic species and differed significantly from the EEGs that were obtained from the normal hamsters. It was concluded from our study that a background activity with an amplitude over 50 µV in combination with a frequency of <5 Hz was highly indicative of hydrocephalus in young hamsters. We believe that the EEG could be a very useful diagnostic tool in the screening for hydrocephalus in hamsters.
Effects of buprenorphine on body temperature, locomotor activity and cardiovascular function when assessed by telemetric monitoring in rats
Authors: Ilbäck N-G , Siller M , Stålhandske T 
Published: April 2008

Summary Buprenorphine is a potent analgesic commonly used clinically in humans and rodents experiencing severe pain. However, effects of therapeutic doses on locomotor activity and the cardiovascular system have not been studied in conscious animals. The effects of buprenorphine were therefore evaluated in this study using telemetric monitoring in conscious animals. Telemetry transmitters were implanted in the peritoneal cavity of Wistar rats with a pressure catheter in the aorta and electrodes for electrocardiogram (ECG) recording subcutaneously. After a single subcutaneous administration of saline, each rat was administered single subcutaneous doses of 0.006, 0.03 or 0.15 mg/kg body weight (bw) of buprenorphine. During a 10 h period after administration, buprenorphine induced a varying dose-dependent increase in body temperature, heart rate, d P/d t and systolic–diastolic blood pressure, as well as a corresponding decrease in QT time. At high dose, however, QT time was still decreased 24 h post-administration, but no arrhythmias or visual changes were observed in the ECG complex. Body temperature and heart rate increased at the high dose of buprenorphine, even at 20–24 h after administration. Moreover, the high dose of buprenorphine induced a biphasic response in diastolic blood pressure, with an early and pronounced increase that, at 14 h after administration, reversed to a decrease, failing to normalize within 24 h post-dosage. The results indicate that buprenorphine induces long-lasting effects (such as body temperature and cardiovascular effects) in the rat after a single subcutaneous dose at 0.15 mg/kg bw.
Comparative effects of halothane, isoflurane, sevoflurane and desflurane on the electroencephalogram of the rat
Authors: Murrell J C , Waters D , Johnson C B 
Published: April 2008

Summary Inhalant anaesthetic agents are commonly used in studies investigating the electroencephalographic (EEG) effects of noxious stimuli in animals. Halothane causes less EEG depression than isoflurane, however, the EEG effects of halothane, isoflurane, sevoflurane and desflurane have not been compared in the same model. This study aimed to compare the EEG effects of these inhalational agents in the rat. Forty male Sprague-Dawley rats were assigned to four groups and anaesthetized with halothane, isoflurane, sevoflurane or desflurane. EEG was recorded from the left and right somatosensory cortices for 5 min at three different multiples of minimal alveolar concentration (MAC) (1.25, 1.5 and 1.75). Median, 95% spectral edge frequency and total power were derived and a single mean value for each was calculated for the first 60 s of each recording period. When the raw EEG contained burst suppression (BS), the BS ratio (BSR) over 60 s was calculated. No BS was found in EEG recorded from the halothane group at any concentration. BS was present at all concentrations with the other anaesthetic agents. BS was almost complete at all concentrations of isoflurane, whereas BSR increased significantly with increasing concentrations of sevoflurane and desflurane. No significant differences were found between the BSR due to the 1.75 MAC multiple of isoflurane, sevoflurane or desflurane. Halothane causes significantly less depression of cortical activity than the newer inhalant agents at equivalent multiples of MAC. These data support the hypothesis that halothane has a fundamentally different mechanism of action than the other inhalant agents.
Direct mixed and open questions in child interviewing: An analog study
Authors: Horowitz Steven W. 
Published: April 2008

Purpose. This study evaluated the relative value of direct questions, open‐ended questions, and mixed questions (including cued invitations) in eliciting accurate statements from young children about a known episode.Methods. Children, 25 aged 5–7 years, and 25 aged 10–12 years, were interviewed concerning a standardized experience the previous week. Direct, mixed, and open‐ended question sequences were counterbalanced between participants. Transcribed videos were assessed for quantity and quality of statements.Results. Mixed questions tended to fall in the middle, between direct and open questions on length of statement, and number of errors. For the younger children, direct questions, but not mixed questions, increased the number of errors of commission in subsequent open question sequences. Cued invitations, where the direct portion of the mixed question pair reiterated information previously elicited from the child, produced fewer errors of omission than mixed questions without adding errors of commission.Conclusions. Mixed questions, especially cued invitations, were found to be a useful alternative for obtaining specific content when open questions alone were not sufficient. Support for conducting the interview in an ‘inverted pyramid’ or ‘funnel’ fashion was found in an analog study where ground truth was firmly established.
Sialochemical and oxidative analyses in radioactive I131-treated patients with thyroid carcinoma
Authors: Ish-Shalom Sophia , Durleshter Lena , Segal Elena , Nagler Rafael M 
Published: April 2008

BackgroundI131 in relatively high doses has been shown in the past to cause damaging salivary effects and oral discomfort in patients. Although lower dosage is now widely accepted, I131 may still be the source of salivary damage over the long-term and subsequent harmful effects on both the oral cavity and the gastrointestinal tract, into which the saliva is swallowed. This study examined the effects of radioactive I131 on salivary gland activity, saliva composition and oxidative profile, and related oral discomfort complaints following thyroidectomy due to carcinoma of thyroid gland.MethodsOut of 40 consenting female post-thyroidectomy patients, 23 (mean age 50±4 years old) were treated with I131 while 17 (mean age 46±4) were not. Whole saliva from all subjects was analyzed for antioxidant and biochemical composition and flow rate.ResultsThe salivary flow rates of both groups were similar but their composition differed considerably. Salivary superoxide dismutase enzyme (SOD), total protein, and albumin concentrations were significantly reduced in the treated patients by 40, 25, and 18% respectively (P<0.05), as were all other salivary antioxidants. Oral discomfort complaints were far more prevalent in the I131-treated patients.ConclusionsI131-dependent damage to the salivary glands was evidenced by a broad spectrum of compositional alterations and oral complaints. Reduction in salivary antioxidant status, SOD enzyme, and the uric acid molecule leaves the oral cavity less protected against oxidative stress. This is the first report of radioactive I131 treatment being harmful to salivary glands due to compromised salivary compositional and oxidative profile and oral discomfort complaints.
Letrozole once a week normalizes serum testosterone in obesity-related male hypogonadism
Authors: Loves Sandra , Ruinemans-Koerts Janneke , de Boer Hans 
Published: April 2008

ObjectiveIsolated hypogonadotropic hypogonadism (IHH) is frequently observed in severely obese men, probably as a result of increased estradiol (E2) production and E2-mediated negative feedback on pituitary LH secretion. Aromatase inhibitors can reverse this process. This study evaluates whether letrozole once a week can normalize serum testosterone in severely obese men and maintain its long term effect.DesignOpen, uncontrolled 6-month pilot study in 12 severely obese men (body mass index>35.0 kg/m2) with obesity-related IHH and free testosterone levels <225 pmol/l, treated with 2.5 mg letrozole once a week for 6 months.ResultsSix weeks of treatment reduced total E2 from 123±11 to 58±7 pmol/l (P<0.001, mean±s.e.m.), and increased serum LH from 4.4±0.6 to 11.1±1.5 U/l (P<0.001). Total testosterone rose from 5.9±0.5 to 19.6±1.4 nmol/l (P<0.001), and free testosterone from 163±13 to 604±50 pmol/l (P<0.001). Total testosterone rose to within the normal range in all subjects, whereas free testosterone rose to supraphysiological levels in 7 out of 12 men. The testosterone and E2 levels were stable throughout the week and during the 6-month treatment period.ConclusionLetrozole 2.5 mg once a week produced a sustained normalization of serum total testosterone in obese men with IHH. However, free testosterone frequently rose to supraphysiological levels. Therefore, a starting dose <2.5 mg once a week is recommended.
Early or advanced stage type 2 diabetes is not accompanied by in vivo skeletal muscle mitochondrial dysfunction
Authors: De Feyter H M , van den Broek N M A , Praet S F E , Nicolay K , van Loon L J C , Prompers J J 
Published: April 2008

ObjectiveSeveral lines of evidence support a potential role of skeletal muscle mitochondrial dysfunction in the pathogenesis of insulin resistance and/or type 2 diabetes. However, it remains to be established whether mitochondrial dysfunction represents either cause or consequence of the disease. We examined in vivo skeletal muscle mitochondrial function in early and advanced stages of type 2 diabetes, with the aim to gain insight in the proposed role of mitochondrial dysfunction in the aetiology of insulin resistance and/or type 2 diabetes.MethodsTen long-standing, insulin-treated type 2 diabetes patients, 11 subjects with impaired fasting glucose, impaired glucose tolerance and/or recently diagnosed type 2 diabetes, and 12 healthy, normoglycaemic controls, matched for age and body composition and with low habitual physical activity levels were studied. In vivo mitochondrial function of the vastus lateralis muscle was evaluated from post-exercise phosphocreatine (PCr) recovery kinetics using 31P magnetic resonance spectroscopy (MRS). Intramyocellular lipid (IMCL) content was assessed in the same muscle using single-voxel 1H MRS.ResultsIMCL content tended to be higher in the type 2 diabetes patients when compared with normoglycaemic controls (P=0.06). The31P MRS parameters for mitochondrial function, i.e. PCr and ADP recovery time constants and maximum aerobic capacity, did not differ between groups.ConclusionsThe finding that in vivo skeletal muscle oxidative capacity does not differ between long-standing, insulin-treated type 2 diabetes patients, subjects with early stage type 2 diabetes and sedentary, normoglycaemic controls suggests that mitochondrial dysfunction does not necessarily represent either cause or consequence of insulin resistance and/or type 2 diabetes.
Activating transcription factor 3: a hormone responsive gene in the etiology of hypospadias
Authors: Beleza-Meireles Ana , Töhönen Virpi , Söderhäll Cilla , Schwentner Christian , Radmayr Christian , Kockum Ingrid , Nordenskjöld Agneta 
Published: April 2008

IntroductionHypospadias is a common inborn error of the genital development, whose complex etiology remains elusive. Defects of the androgen metabolism and activity have been found in a subset of boys with hypospadias. Moreover, the balance between androgens and estrogens seems to be important to the proper male genital development. Activating transcription factor 3 (ATF3), an estrogen responsive gene, has been reported to be expressed during sexual development and up-regulated in hypospadic genital skin. We investigated ATF3 as a candidate gene for hypospadias.Material and methodsGenotyping of eight-tagged single nucleotide polymorphisms (SNP)s was performed in 330 boys with hypospadias and in 380 healthy controls. Screening for mutations in ATF3 was conducted in a subset of boys with hypospadias. ATF3 expression was evaluated in the foreskin of boys with hypospadias and in healthy controls and in the human fetal genitalia by immunohistochemistry.ResultsThree common SNPs, spanning a region of about 16 kb in intron 1 of ATF3, are associated with hypospadias. These SNPs are not linked and their effects are independent. The combination of the three risk SNPs yields the highest significance. Mutation screening identified the gene variant c536A>G in one patient and c817C>T in the 3′-UTR in two other patients. ATF3 expression was evidenced in the developing male urethra.ConclusionsATF3 gene variants influence the risk of hypospadias. Its hormonal responsiveness may underlie this risk effect. But also other ATF3-dependent biological aspects, such as cell survival and death, response to stress stimuli, or the control of epithelial–mesenchymal interactions, may be of importance.
Impact of musculoskeletal disease on quality of life in long-standing acromegaly
Authors: Miller Anne , Doll Helen , David Joel , Wass John 
Published: April 2008

ObjectiveTo provide rheumatological assessment of patients with long-standing acromegaly and investigate the impact of musculoskeletal disease on quality of life.DesignCross-sectional observational study.MethodsFifty-eight patients diagnosed with acromegaly at least 5 years previously were interviewed and examined by a rheumatologist. Each patient completed the short form-36 (SF-36), arthritis impact measurement scales 2 (AIMS2) and acromegaly quality of life questionnaires (AcroQol).ResultsFifty-two out of 58 (90%) reported musculoskeletal pain, with 29 (50%) reporting neck pain. Hip osteoarthritis was present in 49 (84%) and knee osteoarthritis in 20 (34%). Half the patients (52%) reported sleep disturbance, but only 2 (3.5%) had fibromyalgia. Ten (17.2%) had previously undergone carpal tunnel decompression. Fifty-one (88%) patients had consulted their general practioner and 31 (54%) complementary therapists. SF-36, AIMS2 and AcroQol scores were lower in patients with musculoskeletal pain.ConclusionsThis study of musculoskeletal problems in patients with acromegaly reports systematic rheumatological examination, use of medical services and quality of life scores. Musculoskeletal problems should be routinely addressed in acromegaly by both endocrinologist and rheumatologist and a multidisciplinary approach taken to management.