Materials that simultaneously mimic soft tissue in vivo for magnetic resonance imaging (MRI), ultrasound (US), and computed tomography (CT) for use in a prostate phantom have been developed. Prostate ...and muscle mimicking materials contain water, agarose, lipid particles, protein,
Cu
++
,
EDTA, glass beads, and thimerosal (preservative). Fat was mimicked with safflower oil suffusing a random mesh (network) of polyurethane. Phantom material properties were measured at 22 °C. (22 °C is a typical room temperature at which phantoms are used.) The values of material properties should match, as well as possible, the values for tissues at body temperature, 37 °C. For MRI, the primary properties of interest are T1 and T2 relaxations times, for US they are the attenuation coefficient, propagation speed, and backscatter, and for CT, the x-ray attenuation. Considering the large number of parameters to be mimicked, rather good agreement was found with actual tissue values obtained from the literature. Using published values for prostate parenchyma, T1 and T2 at 37 °C and 40 MHz are estimated to be about 1100 and 98 ms, respectively. The CT number for in vivo prostate is estimated to be 45 HU (Hounsfield units). The prostate mimicking material has a T1 of 937 ms and a T2 of 88 ms at 22 °C and 40 MHz; the propagation speed and attenuation coefficient slope are 1540 m/s and 0.36 dB/cm/MHz, respectively, and the CT number of tissue mimicking prostate is 43 HU. Tissue mimicking (TM) muscle differs from TM prostate in the amount of dry weight agarose,
Cu
++
,
EDTA, and the quality and quantity of glass beads. The 18 μm glass beads used in TM muscle increase US backscatter and US attenuation; the presence of the beads also has some effect on T1 but no effect on T2. The composition of tissue-mimicking materials developed is such that different versions can be placed in direct contact with one another in a phantom with no long term change in US, MRI, or CT properties. Thus, anthropomorphic phantoms can be constructed.
SETTING: Sureyyapasa Chest Diseases and Thoracic Surgery Training Hospital, Istanbul, Turkey.OBJECTIVE: To determine levels of Mycobacterium tuberculosis resistance to first-line drugs in patients ...with pulmonary tuberculosis (PTB).DESIGN: Between 1 January and 31 December
2005, all hospitalised PTB patients with culture-positive M. tuberculosis specimens and corresponding drug susceptibility tests (DST) for isoniazid (INH), rifampicin (RMP), streptomycin (SM) and ethambutol, routinely performed for every tuberculosis (TB) case at our centre, were included.RESULTS:
Of a total of 1513 cases, 1277 (84.4%) were new and 236 (15.6%) were previously treated cases. Of the 1513 isolates, 290 (19%) isolates were resistant to at least one of the drugs tested. Resistance among new and previously treated cases was respectively 16.3% (209 of 1277) and 34.3% (81/236).
Any SM resistance and any INH resistance were the most common drug resistance in new cases, while any RMP resistance was the most common drug resistance in previously treated cases. Multidrug resistance was detected in 3.2% (n = 41) of new cases and in 13.5% (n =
32) of previously treated cases.CONCLUSION: Planning for TB control requires an assessment of the number and distribution of drug-resistant cases, with laboratories providing accurate and reliable results.
The hydrodynamic performance of two, recently developed, nanostructured and fluorinated polymer coatings was explored in a systematic experimental study using the Newcastle University Cavitation ...Tunnel. The experiments consisted of testing the two coatings on an axisymmetric body apparatus to measure their boundary layer flow and frictional drag simultaneously. The tests also included a smooth reference surface as well as a state-of-the-art commercial fouling-release coating (Intersleek® 900). The boundary layer measurements were performed using a two-dimensional Laser Doppler Velocimetry (LDV) system whilst the direct frictional force measurements were taken using a special load cell installed in the testing body. Careful surface roughness measurements of the test surfaces were also performed including the use of a non-contact high precision laser profilometer. The tests and subsequent analysis of the data highlighted the exceptionally good frictional properties of all the coatings tested as well as some of the drag benefits of the new polymer coatings in the investigated Reynolds number range.
The extra benefit of adding chemotherapy to effective endocrine therapy (ET) has not been clearly or consistently identified in patients older than 70 years with estrogen receptor (ER) positive and ...node positive breast cancer. The aim of this study was to evaluate the efficacy of adjuvant ET vs. chemotherapy plus endocrine therapies (Chemo/ET) in such patients.
In this retrospective multicenter study 191 patients ≥ 70 years with operated hormone receptor breast cancer, who were administered adjuvant ET or Chemo/ET were assessed.
The median patient follow-up time was 29.0 months (range 1-252). Therefore disease free survival (DFS) and overall survival (OS) analysis was limited, due to the rather short median follow-up, and only 30-month cumulative percentages are reported herein. The 30-month DFS rates were 50.0% in the ET arm and 49.0% in the Chemo/ET arm (p=0.79). The 30-month OS rates were 86% in the ET arm and 96.0% in the Chemo/ET arm (p=0.08). Cox proportional hazard model showed that only surgery was independent prognostic factor for survival (p=0.047), while tumor size showed a strong trend for statistical significance (p=0.051).
The addition of chemotherapy to endocrine therapy in older patients has no significant impact on DFS and OS.
Purpose: Chronic otitis media with effusion (OME) is the leading cause
of hearing loss during childhood. In bacterial etiology of OME, the
most frequent pathogens responsible are Haemophilus ...influenzae
followed by Streptococcus pneumoniae and Moraxella catarrhalis .
This study aimed at evaluating the accuracy of nasopharyngeal (NP)
specimens in the identification of pathogens in the middle ear fluid
(MEF) in patients with OME. Materials and Methods: In this cross
sectional, case-control study, 95 MEFs and 53 NP secretion specimens
were obtained from 53 children. As a control group, 102 NP specimens
were taken from children having an operation other than an otological
disease. Conventional culture methods and multiplex-PCR method have
been used to determine the etiology of OME; NP carriage between cases
and control groups were compared using conventional culture methods.
Pearson Chi-Square and Fisher′s Exact tests were used in
statistical analysis. Results : Bacteria were isolated by culture in
37.9% of MEF specimens, 14.7% of which belonged to the group H.
influenzae , S. pneumoniae and M. catarrhalis. PCR was positive in
30.5% specimens targeting the same pathogens. There was a two-fold
increase in carriage rate of S. pneumoniae and H. influenzae in
patients than controls for each pathogen. Conclusion: PCR is a more
reliable method to detect middle ear pathogens in MEF in comparison
with the conventional culture methods. The NP colonization wasn′t
found to be an indicator of the pathogen in MEF although middle ear
pathogens colonize more in nasopharynx of diseased children.
Preparative reversed-phase HPLC analysis of the methanol extract of the aerial parts of Stachys bombycina (Lamiaceae) afforded two acylated flavonoids glycosides, chrysoeriol ...7-O-6-O-acetyl-β-D-allopyranosyl-(1 → 2)-β-D-glucopyranoside (1)
and apigenin 7-O-β-D-(6-p-coumaroyl)-glucopyranoside (2), the former being a new natural product. The structures of these compounds were elucidated unambiguously by UV spectroscopic analyses using shift reagents, ESIMS, and 1D and 2D NMR spectroscopic techniques.
The free radical scavenging activity of 1 and 2 compounds were assessed by DPPH assay, and the RC50 values were 1.25 × 10-2 and 7.69 × 10-4 mg/mL, respectively.
Polycystic ovary syndrome (PCOS) is clinically heterogeneous endocrine disorders. Insulin resistance-related proteins play a role in the etiopathogenesis of PCOS. Irisin is a newly identified myokine ...which act like adipokines. Irisin has been shown to be associated with the insulin resistance and metabolic syndrome. The purpose of this study was to determine the serum levels of irisin in PCOS patients and evaluate the correlations with other metabolic and hormonal parameters.
Thirty-five PCOS patients and 35 matched healthy controls were enrolled to study. Serum irisin levels, anthropometric, hormonal and metabolic parameters including HOMA-IR were measured. Linear regression analysis was employed to study the relationship between irisin and hormonal and metabolic parameters.
Serum irisin level in PCOS patients (mean value; 0.491±0.145 µg/mL) was significantly elevated when compared to control group (mean value 0.281±0.138 µg/mL) (p < 0.001). Linear regression analysis showed that serum irisin was positively associated with body mass index, luteinizing hormone, fasting insulin and total cholesterol in the overall patient population but not for PCOS group alone (p < 0.05).
Serum irisin level of PCOS patients was high compared to that of healthy control subjects. In patients with PCOS, this situation may be due to insulin resistance, when there is leptin resistance or metabolic syndrome.
Alloys with the nominal composition Mo–12Si–8.5B (at.%) were prepared by arc-melting or powder-metallurgical processing. Cast and annealed alloys consisted of approximately 38 vol.% α-Mo in a brittle ...matrix of 32 vol.% Mo
3Si and 30 vol.% Mo
5SiB
2. Their flexure strengths were approximately 500 MPa at room temperature, and 400–500 MPa at 1200°C in air. The fracture toughness values determined from the three-point fracture of chevron-notched specimens were about 10 MPa m
1/2 at room temperature and 20 MPa m
1/2 at 1200°C in air. The relatively high room temperature toughness is consistent with the deformation of the α-Mo particles observed on fracture surfaces. Three-point flexure tests at 1200°C in air and a tensile test at 1520°C in nitrogen indicated a small amount of high temperature plasticity. Extrusion experiments to modify the microstructure of cast alloys were unsuccessful due to extensive cracking. However, using powder-metallurgical (PM) techniques, microstructures consisting of Mo
3Si and Mo
5SiB
2 particles in a continuous α-Mo matrix were fabricated. The room temperature fracture toughnesss of the PM materials was on the order of 15 MPa m
1/2.
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