Visualizing brain inflammation with a shingled-leg radio-frequency head probe for (19)F/(1)H MRI

Magnetic resonance imaging (MRI) provides the opportunity of tracking cells in vivo. Major challenges in dissecting cells from the recipient tissue and signal sensitivity constraints albeit exist. In this study, we aimed to tackle these limitations in order to study inflammation in autoimmune encephalomyelitis. We constructed a very small dual-tunable radio frequency (RF) birdcage probe tailored for (19)F (fluorine) and (1)H (proton) MR mouse neuroimaging. The novel design eliminated the need for extra electrical components on the probe structure and afforded a uniform -field as well as good SNR. We employed fluorescently-tagged (19)F nanoparticles and could study the dynamics of inflammatory cells between CNS and lymphatic system during development of encephalomyelitis, even within regions of the brain that are otherwise not easily visualized by conventional probes. (19)F/(1)H MR Neuroimaging will allow us to study the nature of immune cell infiltration during brain inflammation over an extensive period of time

Spin Depolarization in Quantum Wires Polarized Spontaneously in a Zero Magnetic Field

The conditions for a spontaneous spin polarization in a quantum wire positioned in a zero magnetic field are analyzed under weak population of one-dimensional subbands that gives rise to the efficient quenching of the kinetic energy by the exchange energy of carriers. The critical linear concentration of carriers above which the quasi one-dimensional gas undergoes a complete spin depolarization is determined by the Hartree-Fock approximation. The dependence of the critical linear concentration on the concentration of carriers is defined to reveal the interplay of the spin depolarization with the evolution of the 0.7 (2e2/h) feature in the quantum conductance staircase from the e2/h to 3/2 (e2/h) values. This dependence is used to study the effect of the hole concentration on the 0.7 (2e2/h) feature in the quantum conductance staircase of the quantum wire prepared inside the p-type silicon quantum well using the split-gate technique. The 1D channel is demonstrated to be spin-polarized at the linear concentration of holes lower than the critical linear concentration, because the 0.7 (2e2/h) feature is close to the value of 0.5 (2e2/h) that indicates the spin degeneracy lifting for the first step of the quantum conductance staircase. The 0.7 (2e2/h) feature is found to take however its normal magnitude when the linear concentration of holes attains the critical value corresponding to the spin depolarization. The variations in the height of the 0.7 (2e2/h) feature observed in the hole quantum conductance staircase that is revealed by the p-type silicon quantum wire seem to be related to the evidences of the quantum conductance staircase obtained by varying the concentration of electrons in the 1D channel prepared inside the GaAs-AlGaAs heterojunction.Comment: 27 pages, 5 figure

Current CONtrolled Transmit And Receive Coil Elements (C2ONTAR) for Parallel Acquisition and Parallel Excitation Techniques at High-Field MRI

A novel intrinsically decoupled transmit and receive radio-frequency coil element is presented for applications in parallel imaging and parallel excitation techniques in high-field magnetic resonance imaging. Decoupling is achieved by a twofold strategy: during transmission elements are driven by current sources, while during signal reception resonant elements are switched to a high input impedance preamplifier. To avoid B0 distortions by magnetic impurities or DC currents a resonant transmission line is used to relocate electronic components from the vicinity of the imaged object. The performance of a four-element array for 3 T magnetic resonance tomograph is analyzed by means of simulation, measurements of electromagnetic fields and bench experiments. The feasibility of parallel acquisition and parallel excitation is demonstrated and compared to that of a conventional power source-driven array of equivalent geometry. Due to their intrinsic decoupling the current-controlled elements are ideal basic building blocks for multi-element transmit and receive arrays of flexible geometry

Association of high risk human papillomavirus and breast cancer : a UK based study

Infection by human papillomaviruses (HPVs) has been implicated in the aetiology of a variety of cancers. Studies evaluating the presence of HPVs in breast cancer (BC) have generated considerable controversy. To date, most studies have focused on the presence of viral DNA in BC; however there are important gaps in evidencing the role of HPV persistence in the invasiveness of BC. While these studies have been conducted in several countries, none, on the presence and biological activity of high risk (HR) HPV in BC has been done in the UK. Hence, we aimed to investigate these gaps by screening a total of 110 fresh breast tissue specimens from UK patients for the presence of twelve HR-HPV types DNA using PCR and Sanger sequencing. Samples positive for HPV-DNA were screened for viral oncoprotein expression using western blot and dot blot. Data obtained showed the presence of HR-HPVs in 42% of breast tissues of which the viral activity was only confirmed in a number of invasive carcinomas (5/26). This finding, the first to report in the UK, suggests that the selective expression of viral oncoprotein in invasive cases may propose a role for HR-HPVs in the development of some types of BC

HPV-Related Nonkeratinizing Squamous Cell Carcinoma of the Oropharynx: Utility of Microscopic Features in Predicting Patient Outcome

Human papilloma virus (HPV) is an etiologic agent in a subset of oropharyngeal squamous cell carcinomas (SCCs). The aim of this study was to sub-classify SCC of the oropharynx based upon histologic features into nonkeratinizing (NK) SCC, keratinizing (K) SCC, and hybrid SCC, and determine the frequency of HPV and patient survival in each group. Patients with oropharyngeal SCC with a minimum of 2 years of clinical follow-up were identified from radiation oncology databases from 1997 to 2004. All patients received either up front surgery with postoperative radiation or definitive radiation based therapy. In situ hybridization (ISH) for high-risk HPV subtypes and immunohistochemistry for p16, a protein frequently up-regulated in HPV-associated carcinomas, were performed. Overall and disease-specific survival were assessed. Of 118 cases, 46.6% were NK SCC, 24.6% K SCC and 28.8% hybrid SCC. NK SCC occurred in slightly younger patients that were more often male. It more frequently presented with lymph node metastases and was surgically resected compared to K SCC. NK SCC was significantly more likely to be HPV and p16 positive than KSCC (P < 0.001) and to have better overall and disease-specific survival (P = 0.0002; P = 0.0142, respectively). Hybrid SCC was also more likely than K SCC to be HPV and p16 positive (P = 0.003; P = 0.002, respectively) and to have better overall survival (P = 0.0105). Sub-classification of oropharyngeal SCC by histologic type provides useful clinical information. NK SCC histology strongly predicts HPV-association and better patient survival compared to K SCC. Hybrid SCC appears to have an intermediate frequency of HPV-association and patient survival

Human Papillomavirus (HPV) in breast tumors: prevalence in a group of Mexican patients

<p>Abstract</p> <p>Background</p> <p>Breast cancer is one of the main health problems in developed countries, occupying first place in mortality in women. It is well-known that there are risk factors associated with breast cancer development. Nonetheless, in 50–80% of cases known risk factors have not been identified, this has generated the attempt to identify new factors related with this neoplasia as viral infections. The aim of this work is investigate the prevalence of HPV DNA in patients with breast lesions at the Instituto Nacional de Cancerologia de Mexico.</p> <p>Methods</p> <p>Fifty-one cases of breast cancer were selected from the files of the institute and compared by age and tumor size with 43 cases of non malignant breast lesions (fibroadenoma, fibrocystic disease and phyllodes tumor). Paraffin embedded specimens were selected, HPV DNA was analyzed by polymerase chain reaction (PCR) and sequenced for different types of HPV in case of positivity for HPV-DNA. Descriptive analysis of clinical and pathological variables was performed and comparisons between positive and negative cases was done.</p> <p>Results</p> <p>All patients were mexican, mean age was 53.3, median age of menarche was 13 and median tumor size 9 cms. Cervicovaginal cytology was performed to all patients, 1 patient (1.9%) of cancer group had HPV and none in the other group, no cases were diagnosed with cervical dysplasia. In the group of carcinomas 36 (70.5%) were negative and 15 (29.4%) were positive to HPV-DNA, 10(66.6%) were positive for HPV 16, 3(20%) for HPV 18, two cases (13.4%) were positive for both. In the group of benign conditions all were negative to HPV-DNA.</p> <p>Conclusion</p> <p>Presence of HPV in breast cancer in our group of cases is high in comparison to other authors; larger numbers of cases need to be analyzed in order to establish the exact role of this virus in the pathogenesis of breast cancer.</p

The Relationship between Oral Squamous Cell Carcinoma and Human Papillomavirus: A Meta-Analysis of a Chinese Population (1994–2011)

Background: Previous studies indicated that oral squamous cell carcinomas (OSCC) might be related to human papilloma virus (HPV) infection. However, up to now, there still lacks a large sample study to analyze the relationship between OSCC in a Chinese population and oral HPV infection. In the present study, we used a meta-analysis to evaluate the relationship of OSCC with HPV infection in a Chinese population. Methods: The reports on HPV and OSCC in a Chinese population published between January, 1994, and September, 2011 were retrieved via CNKI/WANFANG/OVID/MEDLINE databases. According to the inclusion criteria, we selected 18 eligible case-control studies. After testing the heterogeneity of the studies by the Cochran Q test, the meta-analyses for HPV and HPV16 were performed using the fixed effects model. Results: The overall positive rates of HPV and HPV16 in OSCC were 58.0 % (354/610; 95 % confidence interval [CI], 54.1–61.9) and 47.47 % (169/356; 95 % CI: 42.3–52.7), respectively; which were significantly higher than those in normal controls 10.44% (26/249; 95 % CI: 7.2–14.7) and 7.1 % (13/182; 95 % CI: 4.2–11.8). Quantitative meta-analysis revealed that, compared with normal controls, the combined odds ratios of OSCC with HPV or HPV16 infection were 12.7 (95 % CI: 8.0–20.0) and 9.0 (95% CI: 5.1–15.6), respectively. Both Begg’s test and funnel plots revealed that no publication bias was found in this present study (P.0.05)

Phase III trial of postoperative cisplatin, interferon alpha-2b, and 5-FU combined with external radiation treatment versus 5-FU alone for patients with resected pancreatic adenocarcinoma – CapRI: study protocol [ISRCTN62866759]

After surgical intervention with curative intention in specialised centres the five-year survival of patients with carcinoma of the exocrine pancreas is only 15%. The ESPAC-1 trial showed an increased five-year survival of 21% achieved with adjuvant chemotherapy. Investigators from the Virginia Mason Clinic have reported a 5-year survival rate of 55% in a phase II trial evaluating adjuvant chemotherapy, immunotherapy and external-beam radiation. DESIGN: The CapRI study is an open, controlled, prospective, randomised multi-centre phase III trial. Patients in study arm A will be treated as outpatients with 5-Fluorouracil; Cisplatin and 3 million units Interferon alpha-2b for 5 1/2 weeks combined with external beam radiation. After chemo-radiation the patients receive continuous 5-FU infusions for two more cycles. Patients in study arm B will be treated as outpatients with intravenous bolus injections of folinic acid, followed by intravenous bolus injections of 5-FU given on 5 consecutive days every 28 days for 6 cycles. A total of 110 patients with specimen-proven R0 or R1 resected pancreatic adenocarcinoma will be enrolled. An interim analysis for patient safety reasons will be done one year after start of recruitment. Evaluation of the primary endpoint will be performed two years after the last patients' enrolment. DISCUSSION: The aim of this study is to evaluate the overall survival period attained by chemo-radiotherapy including interferon alpha 2b administration with adjuvant chemotherapy. The influence of interferon alpha on the effectiveness of the patients' chemoradiation regimen, the toxicity, the disease-free interval and the quality of life are analysed. Different factors are tested in terms of their potential role as predictive markers