bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of the harmonic scalpel in thyroidectomy
Authors: Parker David J. , Krupa Katherine , Esler Rachel , Vujovic Peter , Bennett Ian C. 
Published: June 2009

AbstractThyroidectomy is a surgical procedure that requires meticulous dissection, safe anatomical exposure and effective haemostasis. Use of the harmonic scalpel in thyroidectomy may assist in achieving these goals, particularly in respect to enabling efficient haemostatic coagulation and division of small vessels. This report demonstrates the results of utilizing the harmonic scalpel in a series of 88 prospective thyroidectomies in patients under the care of two surgeons over a 2‐year period recording a number of parameters, including operative times and post‐operative complications. These data were compared with a retrospective cohort of 57 patients who underwent thyroidectomies by the same two surgeons prior to the introduction of the harmonic scalpel. The results of this study show that the use of the harmonic scalpel decreased surgical operating time by 20 min (22.5%) for a hemithyroidectomy and 13.5 min (12%) for a total thyroidectomy. Harmonic scalpel use was not associated with an increased complication rate and has been demonstrated to be a very efficient and safe tool in assisting with the conduct of a thyroidectomy.
Complete pathologic response after preoperative rectal cancer chemoradiotherapy
Authors: Ciccocioppo Anthony , Stephens Jacqueline H. , Hewett Peter J. , Rieger Nicholas A. 
Published: June 2009

AbstractBackground:  Following preoperative treatment of rectal cancer with chemoradiotherapy (CRT), a complete pathological response (CPR) can be seen in the surgical specimen. The aim of this study was to assess the outcome of these patients as compared with those who did not have a complete response.Methods:  A retrospective study of the outcome of patients managed with preoperative CRT for their rectal cancer was conducted.Results:  Between November 1998 and July 2004, there were 530 new presentations of rectal cancer at The Queen Elizabeth and Royal Adelaide hospitals. Forty of these patients (7.5%) were treated with long‐course preoperative CRT. After resection, a CPR was seen in seven patients (17.5%). These patients were all disease free at January 2006 after a median follow‐up of 6.0 years (range 1.42–7.02 years). One patient had died from non‐tumour‐/surgery‐related causes. Tumour recurrence, but not mortality, in this group was superior to the comparison group of patients without a CPR.Conclusions:  None of our patients who had a CPR after preoperative CRT have recurred or died from their disease.
Epidemiology of post‐injury multiple organ failure in an Australian trauma system
Authors: Dewar David C. , Mackay Peter , Balogh Zsolt 
Published: June 2009

AbstractBackground:  The epidemiology of post‐injury multiple organ failure (MOF) is reported internationally to have gone through changes over the last 15 years. The purpose of this study is to describe the epidemiology of post‐injury MOF in Australia.Methods:  A 12‐month prospective epidemiological study was performed at the John Hunter Hospital (Level‐1 Trauma Centre). Demographics, injury severity (ISS), physiological parameters, MOF status and outcome data were prospectively collected on all trauma patients who met inclusion criteria (ICU admission; ISS > 15; age > 18, head Abbreviated Injury Scale (AIS) <3 and survival >48 h). MOF was prospectively defined by the Denver MOF score greater than 3 points. Data are presented as % or Mean+/−SEM. Univariate statistical comparison was performed (Student t‐test, X2 test), P < 0.05 was considered significant.Results:  Twenty‐nine patients met inclusion criteria (Age 40+/−4, ISS 29+/−3, Male 62%), five patients developed MOF. The incidence of MOF among trauma patients admitted to ICU was 2% (5/204) and 17% (5/29) in the high‐risk cohort. The maximum average MOF score was 6.3 +/−1, with the average duration of MOF 5+/−2 days. Two patients had respiratory and cardiac failure, two patients had failure of respiratory, cardiac and hepatic systems, while one patient had failure of respiratory, hepatic and renal systems. One MOF patient died, all non MOF patients survived. MOF patients had longer ICU stays (20+/−4 versus 7+/−0.8 P= 0.01), tended to be older (60+/−11 versus 35+/−4 p=0.07). None of the previously described independent predictors (ISS, base deficit, lactate, transfusions) were different when the MOF patients were compared with the non‐MOF patients.Conclusion:  The incidence of MOF in Australia is consistent with the international data. In Australia MOF continues to cause significant late mortality and morbidity in trauma patients. MOF patients have longer ICU stay than high‐risk non MOF patients, and use significant resources. Our preliminary data challenges the timeliness of the 10‐year‐old independent predictors of post‐injury MOF. The epidemiology, the clinical presentation and the independent predictors of post‐injury MOF require larger scale reassessment for the Australian context.
Noise‐induced increase in human auditory evoked neuromagnetic fields
Authors: Alain Claude , Quan Jessica , McDonald Kelly , Van Roon Patricia 
Published: June 2009

AbstractNoise is usually detrimental to auditory perception. However, recent psychophysical studies have shown that low levels of broadband noise may improve signal detection. Here, we measured auditory evoked fields (AEFs) while participants listened passively to low‐pitched and high‐pitched tones (Experiment 1) or complex sounds that included a tuned or a mistuned component that yielded the perception of concurrent sound objects (Experiment 2). In both experiments, stimuli were embedded in low or intermediate levels of Gaussian noise or presented without background noise. For each participant, the AEFs were modeled with a pair of dipoles in the superior temporal plane, and the effects of noise were examined on the resulting source waveforms. In both experiments, the N1m was larger when the stimuli were embedded in low background noise than in the no‐noise control condition. Complex sounds with a mistuned component generated an object‐related negativity that was larger in the low‐noise condition. The results show that low‐level background noise facilitates AEFs associated with sound onset and can be beneficial for sorting out concurrent sound objects. We suggest that noise‐induced increases in transient evoked responses may be mediated via efferent feedback connections between the auditory cortex and lower auditory centers.
Wide‐ranging frequency preferences of auditory midbrain neurons: Roles of membrane time constant and synaptic properties
Authors: Yang Sungchil , Lin Wenyu , Feng Albert S. 
Published: June 2009

AbstractPeriodicity is a fundamental sound attribute. Its coding has been the subject of intensive research, most of which has focused on investigating how the periodicity of sounds is processed through the synaptic machinery in the brain. The extent to which the intrinsic properties of cells play in periodicity coding, particularly in the creation of selectivity to periodic signals, is not well understood. We performed in vitro whole‐cell patch recordings in the frog torus semicircularis to investigate each neuron’s intrinsic membrane properties as well as responses to sinusoidal current injected through the electrode and periodic stimulation of the ascending afferent. We found that: (i) toral neurons were heterogeneous, showing diverse biophysical phenotypes having distinct membrane characteristics, including membrane time constants (τ) and ionic channel compositions (Ih, Ikir, Ikv and INaP); (ii) a neuron’s τ was tightly correlated with its current‐evoked frequency preference (FP; range: 0.05–50 Hz); (iii) application of blockers for Ih, Ikir and Ikv (but not INaP) shifted the τ as well as the cell’s current‐evoked FP, suggesting that these ion channels contribute to the cell’s FP through regulation of τ; (iv) a neuron’s τ was also correlated with its afferent‐evoked FP (range: 10–300 pulses/s); and (v) the range of afferent‐evoked FP was approximately one order higher than the range of current‐evoked FPs, suggesting that both the cell’s intrinsic membrane and synaptic properties contribute to determining the afferent‐evoked cell‐specific FP (whose range matched those of cell‐specific responses to sound stimulation, e.g. selectivity to amplitude modulation rate).
Neuropathic pain in spinal cord injury: significance of clinical and electrophysiological measures
Authors: Wydenkeller Susanne , Maurizio Stefano , Dietz Volker , Halder Pascal 
Published: June 2009

AbstractA large percentage of spinal cord‐injured subjects suffer from neuropathic pain below the level of the lesion (bNP). The neural mechanisms underlying this condition are not clear. The aim of this study was to elucidate the general effects of spinal deafferentiation and of bNP on electroencephalographic (EEG) activity. In addition, the relationship between the presence of bNP and impaired function of the spinothalamic tract was studied. Measurements were performed in complete and incomplete spinal cord‐injured subjects with and without bNP as well as in a healthy control group. Spinothalamic tract function, assessed by contact heat evoked potentials, did not differ between subjects with and without bNP; nevertheless, it was impaired in 94% of subjects suffering from bNP. In the EEG recordings, the degree of deafferentiation was reflected in a slowing of EEG peak frequency in the 6–12‐Hz band. Taking into account this unspecific effect, spinal cord‐injured subjects with bNP showed significantly slower EEG activity than subjects without bNP. A discrimination analysis in the subjects with spinothalamic tract dysfunction correctly classified 84% of subjects as belonging to either the group with bNP or the group without bNP, according to their EEG peak frequency. These findings could be helpful for both the development of an objective diagnosis of bNP and for testing the effectiveness of new therapeutic agents.
Perceptual influence on bimanual coordination: an fMRI study
Authors: Müller Katharina , Kleiser Raimund , Mechsner Franz , Seitz Rüdiger J. 
Published: June 2009

AbstractIn bimanual coordination subjects typically show a spontaneous preference for movement symmetry. While there is experimental evidence for the principle of muscle homology, recent evidence suggested that bimanual coordination may be mediated as perceptual goals (Mechsner et al., 2001). To explore this controversy we performed a fMRI study in 11 healthy, right‐handed subjects using bimanual index finger abductions and adductions in a congruous condition, i.e. both palms down, and incongruous conditions with either the left or right palm up. Our fMRI data showed a widespread bihemispheric network mediating proprioceptive coordination of the two hands with significant differences mainly for a perceptual dissociation: in the incongruous conditions with the one palm up there was a BOLD signal increase in a bilateral frontoparietal network involving the motor and premotor cortical areas, particularly in the right palm‐up condition. These results accord with the notion that perceptual cues play an important role in the control of bilateral hand movements.
Attentional modulation of adaptation in V4
Authors: Hudson Andrew E. , Schiff Nicholas D. , Victor Jonathan D. , Purpura Keith P. 
Published: June 2009

AbstractAdaptation and visual attention are two processes that alter neural responses to luminance contrast. Rapid contrast adaptation changes response size and dynamics at all stages of visual processing, while visual attention has been shown to modulate both contrast gain and response gain in macaque extrastriate visual cortex. Because attention aims to enhance behaviorally relevant sensory responses while adaptation acts to attenuate neural activity, the question we asked is, how does attention alter adaptation? We present here single‐unit recordings from V4 of two rhesus macaques performing a cued target detection task. The study was designed to characterize the effects of attention on the size and dynamics of a sequence of responses produced by a series of flashed oriented gratings parametric in luminance contrast. We found that the effect of attention on the response dynamics of V4 neurons is inconsistent with a mechanism that only alters the effective stimulus contrast, or only rescales the gain of the response. Instead, the action of attention modifies contrast gain early in the task, and modifies both response gain and contrast gain later in the task. We also show that responses to attended stimuli are more closely locked to the stimulus cycle than unattended responses, and that attended responses show less of the phase lag produced by adaptation than unattended responses. The phase advance generated by attention of the adapted responses suggests that the attentional gain control operates in some ways like a contrast gain control utilizing a neural measure of contrast to influence dynamics.
The GluR2 subunit inhibits proliferation by inactivating Src‐MAPK signalling and induces apoptosis by means of caspase 3/6‐dependent activation in glioma cells
Authors: Beretta Francesca , Bassani Silvia , Binda Elena , Verpelli Chiara , Bello Lorenzo , Galli Rossella , Passafaro Maria 
Published: June 2009

AbstractGlioblastoma multiforme (GBM) is the most invasive and undifferentiated type of brain tumour, and so surgical interventions are ineffective. We found that GluR2 is absent in fast‐growing GBM‐derived tumour stem cells and high‐grade glioma specimens, but is expressed in slow‐growing stem cells and low‐grade glioma specimens. More remarkably, GluR2 overexpression in U‐87MG cells inhibits proliferation by inactivating extracellular signal‐regulated kinase (ERK)1/2‐Src phosphorylation and induces apoptosis. Mechanistically, we observed that the scaffold protein GRIP is essential for the effect of GluR2 on ERK‐Src inactivation. These findings indicate that the absence of the GluR2 subunit favours malignancy.
Molecular analysis of the phosphorus starvation response in Trichodesmium spp.
Authors: Orchard Elizabeth D. , Webb Eric A. , Dyhrman Sonya T. 
Published: June 2009

SummaryThe marine diazotroph Trichodesmium is a major contributor to primary production and nitrogen fixation in the tropical and subtropical oceans. These regions are often characterized by low phosphorus (P) concentrations, and P starvation of Trichodesmium could limit growth, and potentially constrain nitrogen fixation. To better understand how this genus responds to P starvation we examined four genes involved in P acquisition: two copies of a high‐affinity phosphate binding protein (pstS and sphX) and two putative alkaline phosphatases (phoA and phoX). Sequence analysis of these genes among cultured species of Trichodesmium (T. tenue, T. erythraeum, T. thiebautii and T. spiralis) showed that they all are present and conserved within the genus. In T. erythraeum IMS101, the expression of sphX, phoA and phoX were sensitive to P supply whereas pstS was not. The induction of alkaline phosphatase activity corresponded with phoA and phoX expression, but enzyme activity persisted after the expression of these genes returned to basal levels. Additionally, nifH (nitrogenase reductase; involved in nitrogen fixation) expression was downregulated under P starvation conditions. These data highlight molecular level responses to low P and lay a foundation for better understanding the dynamics of Trichodesmium P physiology in low‐P environments.
Chromosomal antioxidant genes have metal ion‐specific roles as determinants of bacterial metal tolerance
Authors: Harrison Joe J. , Tremaroli Valentina , Stan Michelle A. , Chan Catherine S. , Vacchi‐Suzzi Caterina , Heyne Belinda J. , Parsek Matthew R. , Ceri Howard , Turner Raymond J. 
Published: June 2009

SummaryMicrobiological metal toxicity involves redox reactions between metal species and cellular molecules, and therefore, we hypothesized that antioxidant systems might be chromosomal determinants affecting the susceptibility of bacteria to metal toxicity. Here, survival was quantified in metal ion‐exposed planktonic cultures of several Escherichia coli strains, each bearing a mutation in a gene important for redox homeostasis. This characterized ∼250 gene–metal combinations and identified that sodA, sodB, gor, trxA, gshA, grxA and marR have distinct roles in safeguarding or sensitizing cells to different toxic metal ions (Cr2O72–, Co2+, Cu2+, Ag+, Zn2+, AsO2–, SeO32– or TeO32–). To shed light on these observations, fluorescent sensors for reactive oxygen species (ROS) and reduced thiol (RSH) quantification were used to ascertain that different metal ions exert oxidative toxicity through disparate modes‐of‐action. These oxidative mechanisms of metal toxicity were categorized as involving ROS and thiol‐disulfide chemistry together (AsO2–, SeO32–), ROS predominantly (Cu2+, Cr2O72–) or thiol‐disulfide chemistry predominantly (Ag+, Co2+, Zn2+, TeO32–). Corresponding to this, promoter‐luxCDABE fusions showed that toxic doses of different metal ions up‐ or downregulate the transcription of gene sets marking distinct pathways of cellular oxidative stress. Altogether, our findings suggest that different metal ions are lethal to cells through discrete pathways of oxidative biochemistry, and moreover, indicate that chromosomally encoded antioxidant systems may have metal ion‐specific physiological roles as determinants of bacterial metal tolerance.
A mid‐gut microbiota is not required for the pathogenicity of Bacillus thuringiensis to diamondback moth larvae
Authors: Raymond Ben , Johnston Paul R. , Wright Denis J. , Ellis Richard J. , Crickmore Neil , Bonsall Michael B. 
Published: June 2009

SummaryThe mode of action of the entomopathogenic bacterium Bacillus thuringiensis (Bt) remains a matter of debate. Recent reports have claimed that aseptic lepidopteran hosts were not susceptible to Bt and that inoculation with mid‐gut bacteria restores pathogenicity. These claims are controversial because larvae were rendered aseptic by consuming antibiotics, although the effect of these antibiotics on Bt was not examined. We tested the generality of the mid‐gut bacteria hypothesis in the diamondback moth, Plutella xylostella using properly controlled experiments that investigated the effect of antibiotic consumption and absence of gut microbiota separately. We found that purified Bt toxin and spore/toxin mixtures were fully pathogenic to larvae reared aseptically. Persistence of antibiotics in larval tissues was implicated in reducing host mortality because larval consumption of the antibiotic rifampicin reduced the pathogenicity of rifampicin‐sensitive Bt strains but not rifampicin‐resistant strains. Inoculating larvae with Enterobacter sp. Mn2 reduced the mortality of larvae feeding on Bt HD‐1 and the presence of a culturable gut microbiota also reduced the pathogenicity of the Bt toxin Cry1Ac, in agreement with other studies indicating that an intestinal microbiota can protect taxonomically diverse hosts from pathogen attack. As ingestion of antibiotics suppresses host mortality the vegetative growth of Bt in the host must be important for its pathogenicity. Furthermore, claims that aseptic larvae are not susceptible to Bt must be supported by experiments that control for the effect of administering antibiotics.
Comparison of the prognostic value of tumour‐ and patient‐related factors in patients undergoing potentially curative surgery for colon cancer
Authors: Roxburgh C. S. D. , Wallace A. M. , Guthrie G. K. , Horgan P. G. , McMillan D. C. 
Published: June 2009

AbstractAim  To comprehensively compare the prognostic value of tumour‐ and patient‐related factors in patients undergoing curative surgery for colon cancer.Method  From a database of 287 patients who underwent elective resection between 1997 and 2005, tumour factors including stage and host factors including systemic inflammatory response [modified Glasgow Prognostic Score (mGPS)] were identified.Results  Median follow‐up was 65 months. Over this period, 125 patients died, 80 from cancer. On multivariate analysis of all significant patient and tumour related factors, Dukes stage (P < 0.01), vascular invasion (P < 0.01) and the mGPS (P < 0.01) were independently associated with cancer‐survival. Of the patient‐related factors, age (P < 0.01), haemoglobin (P < 0.01), white‐cell (P < 0.01), neutrophil (P < 0.01) and platelet (P < 0.01) counts, and alkaline phosphatase (P < 0.01) were most significantly associated with the mGPS.Conclusion  In addition to tumour‐related factors such as Dukes stage and vascular invasion, the preoperative mGPS should be included to guide prognosis in patients undergoing curative resection for colon cancer.
The impact of lymph node yield on Duke’s B and C colorectal cancer survival
Authors: Fretwell V. L. , Ang C. W. , Tweedle E. M. , Rooney P. S. 
Published: June 2009

AbstractAim  The number of positive lymph nodes retrieved following colorectal cancer (CRC) resection impacts on the staging and further treatment of the disease. We compared 5‐year survival by lymph node yield for Duke’s B and C patients to assess the impact on prognosis.Method  A retrospective methodology was employed to review patients who underwent operative resection for Duke’s B or C CRC between 1999 and 2003.Results  A total of 351 patients were included in our analyses. Lymph node yield, N‐stage and extramural vascular invasion were independent predictors of overall 5‐year survival. A significant difference in 5‐year survival by lymph node yield was seen among Duke’s B patients (< 9 nodes vs≥ 9 nodes, 45.2%vs 68.4%; P = 0.0043) and Duke’s C patients (< 10 nodes vs≥ 10 nodes, 25.6%vs 48.8%; P = 0.0099). There was a significant reduction in the relative risk of 2.8% in mortality for each additional node sampled in Duke’s B and C patients (RR 0.972, 95% confidence interval 0.949–0.994, P = 0.0102). Duke’s B patients who had < 9 lymph node yield and no neoadjuvant/adjuvant treatment had a similar survival to all Duke’s C patients (47.8%vs 41.7%, P = 0.5136).Conclusion  Lymph node yield independently predicts for survival in patients with Duke’s B and C CRC. Duke’s B patients with < 9 lymph node yield have no better survival than patients with Duke’s C disease. Therefore, prospective randomized studies are required to examine if inadequate lymph node yield could be one of the deciding factors in offering adjuvant therapy among Duke’s B cancer patients.