Continuous flow biocatalysis: synthesis of purine nucleoside esters catalyzed by lipase TL IM from Thermomyces lanuginosus.

Purine nucleoside ester is one of the derivatives of purine nucleoside, which has antiviral and anticancer activities. In this work, a continuous flow synthesis of purine nucleoside esters catalyzed by lipase TL IM from Thermomyces lanuginosus was successfully achieved. Various parameters including solvent, reaction temperature, reaction time/flow rate and substrate ratio were investigated. The best yields were obtained with a continuous flow microreactor for 35 min at 50 °C with the substrate ratio of 1 : 5 (nucleosides to vinyl esters) in the solvent of tert-amyl alcohol. 12 products were efficiently synthesized with yields of 78-93%. Here we reported for the first time the use of lipase TL IM from Thermomyces lanuginosus in the synthesis of purine nucleoside esters. The significant advantages of this methodology are a green solvent and mild conditions, a simple work-up procedure and the highly reusable biocatalyst. This research provides a new technique for rapid synthesis of anticancer and antiviral nucleoside drugs and is helpful for further screening of drug activity.

Development of a green, concise synthesis of nicotinamide derivatives catalysed by Novozym® 435 from Candida antarctica in sustainable continuous-flow microreactors.

An increasing number of studies have shown that many nicotinamide derivatives exhibited extensive biological activities, such as anti-inflammatory and antitumor activity. In this paper, a green, concise synthesis of nicotinamide derivatives in sustainable continuous-flow microreactors catalysed by Novozym® 435 from Candida antarctica has been developed. Application of an easily obtainable and reusable lipase in the synthesis of nicotinamide derivatives from methyl nicotinate and amines/benzylamines reacted for 35 min at 50 °C led to high product yields (81.6-88.5%). Environmentally friendly tert-amyl alcohol was applied as a reaction medium. Substantially shorter reaction times as well as a significant increase in the product yield were obtained as compared to the batch process. This innovative approach provides a promising green, efficient and rapid synthesis strategy for pharmaceutical synthesis and further activity research of novel nicotinamide derivatives.

A novel QA phantom based on scintillating fiber ribbons with implementation of 2D dose tomography for small-field radiotherapy.

PURPOSE: To develop a novel instrument for real-time quality assurance (QA) procedures in radiotherapy. The system implements a scintillation-based phantom and associated signal acquisition and processing modules and aims to monitor two-dimensional (2D) dose distributions of small fields. MATERIALS AND METHODS: For the proposed phantom, we have designed and realized a prototype implementing six high-resolution tissue-equivalent scintillating fiber ribbons stacked with in-plane 30° rotated orientations from each other. Each ribbon output is coupled to a silicon photodiode linear array (with an element pitch of 400 µm) to detect scintillating signal, which represents the projected irradiation profile perpendicular to the ribbon's orientation. For the system providing six acquired projected dose profiles at different orientations, we have developed a two-step signal processing method to perform 2D dose reconstruction. The first step is to determine irradiation field geometry parameters using a tomographic geometry approach, and the second one is to perform specific penumbra estimation. The QA system prototype has been tested on a Novalis TrueBeam STX with a 6-MV photon beam for small elliptic fields defined by 5- and 10-mm cone collimators and for 10 × 10- and 20 × 10-mm2 rectangular fields defined by the micro-multileaf collimator. Gamma index analysis using EBT3 films as reference has been carried out with tight 2%-dose-difference (DD)/700-µm-distance-to-agreement (DTA) as well as 1%-DD/1-mm-DTA criteria for evaluating the system performances. The testing also includes an evaluation of the proposed two-step field reconstruction method in comparison with two conventional methods: filtered back projection (FBP) and simultaneous iterative reconstruction technique (SIRT). RESULTS: The reconstructed 2D dose distributions have gamma index pass rates higher than 95% for all the tested configurations as compared with EBT3 film measurements with both 2%-DD/700-µm-DTA and 1%-DD/1-mm criteria. 2D global gamma analysis shows that the two-step and FBP radiation field reconstruction methods systematically outperform the SIRT approach. Moreover, higher gamma index success rates are obtained with the two-step method than with FBP in the case of the fields defined with the stereotactic cones. CONCLUSIONS: The proposed small-field QA system makes a use of six water-equivalent scintillating detectors (fiber ribbons) to acquire dose distribution. The developed two-step signal processing method performs tomographic 2D dose reconstruction. A system prototype has been built and tested using hospital facilities with small rectangular and elliptic fields. Testing results show 2D reconstructed dose distributions with high accuracy and resolution. Such a system could potentially be an alternative approach to film dosimetry for small-field QA, which is still widely used as reference in clinical practice.

Aneurysmal bone cyst of the proximal femur concomitant with Graves' disease and Moyamoya disease: report of a rare case.

Aneurysmal bone cyst is a type of benign bone pathology with expansile and osteolytic features whose etiology remains unclear. Graves' disease is an autoimmune disease characterized by diffuse goiter and hyperthyroidism. Moyamoya disease is a progressive cerebral vasculopathy. It has been reported that Graves' disease and Moyamoya disease share a similar etiology involving cytokines and autoimmune and genetic factors. There are no previous reports regarding the relationship between aneurysmal bone cyst and Graves' disease. Here, we present the rare case of a 25-year-old woman with suspected aneurysmal bone cyst of the left proximal femur and a definite preoperative diagnosis of Graves' disease, in whom lesion resection combined with left total hip replacement was indicated. Biopsy confirmed the diagnosis of aneurysmal bone cyst. Three days postoperatively, the patient developed acute ischemic cerebral infarction owing to Moyamoya disease, which was subsequently confirmed. This case elucidates the potential interaction among aneurysmal bone cysts, Graves' disease, and Moyamoya disease and provides lessons regarding appropriate perioperative preparation for patients with Graves' disease who require surgery to avoid potential severe complications.

Fully Depleted, Trench-Pinned Photo Gate for CMOS Image Sensor Applications.

Tackling issues of implantation-caused defects and contamination, this paper presents a new complementary metal-oxide-semiconductor (CMOS) image sensor (CIS) pixel design concept based on a native epitaxial layer for photon detection, charge storage, and charge transfer to the sensing node. To prove this concept, a backside illumination (BSI), p-type, 2-µm-pitch pixel was designed. It integrates a vertical pinned photo gate (PPG), a buried vertical transfer gate (TG), sidewall capacitive deep trench isolation (CDTI), and backside oxide-nitride-oxide (ONO) stack. The designed pixel was fabricated with variations of key parameters for optimization. Testing results showed the following achievements: 13,000 h+ full-well capacity with no lag for charge transfer, 80% quantum efficiency (QE) at 550-nm wavelength, 5 h+/s dark current at 60 °C, 2 h+ temporal noise floor, and 75 dB dynamic range. In comparison with conventional pixel design, the proposed concept could improve CIS performance.

Fan-Beam Based Virtual Fluoroscopy for Navigated Catheterization in Interventional Radiology.

Personalized medicine implies reducing invasiveness of therapeutic procedures. Although interventional radiology proved a very interesting alternative to surgical procedures, it still raises concerns due to the irradiation dose received by the medical team (and by the patient). We propose a novel concept allowing to reduce very significantly the irradiation dose during the phases where tools inserted in the patient have to be tracked with respect to previously acquired images. This implies inserting a miniaturized X-ray detector in the tip of the tools, and reducing the dose by a "rotating collimator". We demonstrate that real-time processing of the signals allows accurate localization of the tip of the tools, with a dose reduction of at least ten times.

Expanded Paramedian Forehead Flaps for Nasal Defects: Beyond Aesthetic Subunits.

BACKGROUND: Reconstruction of nasal tip defects presents a significant challenge for plastic surgeons. The form, function, and aesthetic appeal of all nasal subunits must be addressed. The expanded paramedian forehead flap is a good choice for nasal reconstruction, providing similar texture, structure, and skin color, and high reliability. This article discusses the authors' modification of the expanded paramedian forehead flap in reconstructing defects on or around the nasal tip. METHODS: Twenty-two patients with nasal defects located on or around the nasal tip were treated in our institution. Sixteen patients underwent nasal reconstruction with expanded forehead flaps. The other 6 cases with cartilage defect underwent reconstruction with expanded forehead flaps and autogenous rib cartilage grafts. Functional and cosmetic results were assessed by surgeon, patient, and patient's relatives using a scale from 1 to 10. RESULTS: The aesthetic appearance of all patients was significantly improved after surgery. Two cases had mild hyperpigmentation. Two patients considered the flaps too thick. Three cases had minor brow elevation at the donor site. There were no obvious scars at the donor sites. There were no serious complications, such as infection, flap necrosis, deviation, or collapse. CONCLUSIONS: The expanded paramedian forehead flap is a safe and effective method for reconstructing defects located on or around the nasal tip. Moreover, this technique can result in good functional and cosmetic outcomes with very few complications.

[Study of the last glacial loess-like deposits in the coastal area of South China with diffuse reflectance spectroscopy and laser particle size analysis].

Newly discovered yellow silt widely distributed in the coastal area of south China was analyzed using diffuse reflectance spectroscopy (DRS) and laser particle size (LPS) methods in the present paper. The authors take the lead in trying to synthetically judge the depositional environment, transporting agent and forming mechanism of the yellow silt from angles of output forms of iron minerals as well as grain size distribution features of the samples chose from three representative sections and a drill core. The DRS first derivative curves show the peak height of iron minerals decreasing from hematite (565 nm) to goethite (505 and 435 nm), which reflects a relatively dry, cold climate that coincides with the aeolian loess widely distributed in the northwest China, but reverses of the fluvial and marine deposits which experienced a well hydration in humid conditions over a long period of time in study area. LPS analysis show that grain size from top to bottom of the sections and drill core are homogeneous and typical of aeolian sediments. The grain size distribution in the yellow silt is characterized by double peaks with main peak of 10-50 µm and a secondary peak of < 5 µm, similar to that of loess in northwest China but quite different from associated fluvial and marine deposits featured by unidirectional change of allocation mode of the grain size groups. Based on grain size analysis, DRS results, age range of 10-80 ka, and spatial distribution that both of the positive landforms and buried topographies in the coastal area of south China have this kind of sediments, the yellow silt is considered to represent an aeolian deposit formed during the last glacial period, which is called "loess-like deposits" in our study.

A novel method for creating working space during endoscopic thyroidectomy via bilateral areolar approach.

BACKGROUND: Endoscopic thyroidectomy (ET) can be performed through the bilateral areolar approach (BAA). A working space (WS) is typically created on the surface of the pectoral fascia in the chest wall and in the subplatysmal space in the neck. There are several limitations of using this WS. The aim of this study was to establish a new WS for ET. SUBJECTS AND METHODS: A retrospective review was performed on 85 patients with benign thyroid nodules who had undergone ET through a BAA. A WS was created between the anterior and poster layers of the superficial pectoral fascia (SPF) in the chest and underneath the deep layer of the investing layer (IL) in the neck. RESULTS: The time for creating the WS was 7.2 ± 2.1 (range, 5-12) minutes. No hemorrhage occurred during the procedure. Fat liquefaction occurred in 2 patients. Edema of the neck skin flap presented as lack of a suprasternal notch. No skin numbness occurred. No patient required postoperative pain medication. All patients were extremely satisfied with the cosmetic results. CONCLUSIONS: This new method of establishing a WS between the two layers of the SPF and underneath the IL is simple and fast, provides good exposure, yields less postoperative pain, and has a lower risk of skin burn.

Implementation and validation of a fluence pencil kernels model for GaN-based dosimetry in photon beam radiotherapy.

Gallium nitride (GaN), a direct-gap semiconductor that is radioluminescent, can be used as a transducer yielding a high signal from a small detecting volume and thus potentially suitable for use in small fields and for high dose gradients. A common drawback of semiconductor dosimeters with effective atomic numbers higher than soft tissues is that their responses depend on the presence of low energy photons for which the photoelectric cross section varies strongly with atomic number, which may affect the accuracy of dosimetric measurements. To tackle this 'over-response' issue, we propose a model for GaN-based dosimetry with readout correction. The local photon spectrum is calculated by convolving fluence pencil kernel spectra with the beam aperture fluence distribution. The response of a GaN detector is modelled by combining large cavity theory and small cavity theory for the low and high energy components of the local spectrum. Monte Carlo simulations are employed for determination of specific correction factors for different GaN transducer sizes and irradiation conditions. Some model parameters such as the cut-off energy and partitioning energy are discussed. The accuracy of the GaN dosimetric response model has been evaluated for tissue phantom ratio experiments along the central axis. These experiments have shown that calculated and measured GaN responses stay within ±3% at all depths beyond the build-up depth. The calculated GaN response factor is also in good agreement with measured data (±2.5%). The validated model with response compensation improves significantly the accuracy of dosimetric measurements: below 2.5% deviation as compared to 13% without compensation, for a 10 × 10 cm(2) field, at depth from 1.5 to 22 cm.

[Comparison of fluorescence spectroscopy and plasma-mass spectrometry results of the Meso/Cenozoic basic rocks in SE China and its geo-implication].

With comparison of the fluorescence spectroscopy and plasma-mass spectroscopy analysis results of the Meso/Cenozoic basic rocks of SE China, the authors found that the average SiO2 content of the Mesozoic basic rocks in this area is about 50%, while that of the Cenozoic basic rocks is about 43%. The former belongs to the basic group and the later to the ultrabasic group in igneous rock classification. Cenozoic basalts, accompanied with high magnesium content and low silica-alumina component, are obviously basic or ultrabasic rocks. Distinctive difference in the content of trace elements and of REE is also presented between the Mesozoic and the Cenozoic basic rocks. Distribution models of both trace elements and REE of the Mesozoic basic rocks are similar to those of the upper crust, and the models of the Cenozoic basic rocks are like those of OIB, indicating that basic rocks of the Cenozoic and OIB should originate from the mantle while that of the Mesozoic is from the bottom part of the upper crust with relationship to the evolution of the Mesozoic crustal magma layer of this area.

[Analysis of X-ray fluorescence spectroscopy and plasma mass spectrometry of the Guidong granite body and its implications to granite evolution].

The Guidong composite granite body (CGB) located in the north Guangdong Province consists of numerous rock bodies formed respectively in the early and late Jurassic and early Cretaceous. Analysis of the granites of different period with X-ray fluorescence spectroscopy and plasma mass spectrometry indicates: (1) From the top of a granite body downwards, the felsic components of rock decrease, while the mafic and sigmaREE, LREE/HREE, (La/Yb)N, as well as delta Eu value increase, suggesting the material differentiation in the in-situ melting of crustal rocks and crystallisation of magma; (2) From old to young of the different period granite-massifs in the Guidong CGB, the felsic compositions totally decrease, and the mafic components, sigmaEE, LREE/HREE, (La/Yb)N, and delta Eu value increase as well, implying multiple crustal melting (remelting) events in the Mesozoic in this area; and (3) Primitive mantle-normalized spider diagram for trace elements of Guidong CGB suggests high maturity of the crust involved in the in-situ melting.

[Discussion on diagenesis of Xilingang pluton-constrained by X-ray Fluorescence spectroscopy, plasma mass spectrometry and Raman spectroscopy].

The results on Xilingang pluton, mainly consisting of red beds, granites containing numerous debris of red beds and granites, obtained by X-ray fluorescence spectroscopy, plasma mass spectrometry and Raman spectroscopy show: (1) Xilingang pluton from red beds, granites containing numerous debris of red beds to granites has obvious characteristics of decreasing silicon and alkali content, and rising ignition loss, dark mineral content and oxidation index; (2) Chondrite-normalized REE distribution curves and primitive mantle-normalized spider diagram for trace elements of redbed, granites containing numerous debris of red beds and granites have a good consistency, the distribution characteristics of elements are similar to Nanling transformation-type granite; (3) The value of Raman spectrogram characteristic peak of quartz crystal in Xilingang granite decreased from the center of quartz crystal, and FWHM is steady. According to the above, the authors believe that Xilingang granite formed was related to in-situ melting of red beds and underlying strata and magma consolidation. Volatile components were discharged continuously, and oxidation index decreased gradually in the melting process. In the process of diagenesis, the top of pluton tend to be an ongoing silicon and alkali increase, while TFeO and MgO continue to migrate to bottom, and crystallization environment is a relatively closed and steady system.

[Comparison study of clinical effect and complications between subfascial and submammary breast augmentation].

OBJECTIVE: To compare the clinical effect and complications of subfascial breast augmentation and submammary breast augmentation. METHOD: From Sept. 2009 to May 2012 , 25 patients with subfascial breast augmentation and 31 patients with submammary breast augmentation were observed. The postoperative results including visible implant edge or ripple, upper pole of the implant and long-term implant ptosis were compared respectively. The complications including hematoma, infection and capsular contraction were also recorded. RESULTS: 56 cases were followed up for 2 months to 26 months. The incidence rate of visible implant edge or ripple was 4.0% (1/25 ) in the subfascial group and 29.0% (9/31) in the submammary group, showing a significant difference between them ( PC 0.05). The incidence rate of convex upper pole of the implant was 8.0% (2/25) in the subfascial group and 35.5% (11/31) in the submammary group, showing a significant difference between them ( P < 0.05). Long-term implant ptosis was not found in the two groups. The incidence rate of hematoma was 4.0% (1/25) in the subfascial group and 6.5% (2/31) in the submammary group, infection was not found. The incidence rate of capsular contraction was 8.0% (2/25) in the subfascial group and 12.9% (4/31) in the submammary group, showing no statistical difference between them ( P > 0.05 ). CONCLUSIONS: Subfascial breast augmentation has more clinical advantages compared with submammary breast augmentation, but no evident difference was found in the common complication rate, such as capsular contraction.

Surface structural-chemical characterization of a single-site d0 heterogeneous arene hydrogenation catalyst having 100% active sites.

Structural characterization of the catalytically significant sites on solid catalyst surfaces is frequently tenuous because their fraction, among all sites, typically is quite low. Here we report the combined application of solid-state (13)C-cross-polarization magic angle spinning nuclear magnetic resonance ((13)C-CPMAS-NMR) spectroscopy, density functional theory (DFT), and Zr X-ray absorption spectroscopy (XAS) to characterize the adsorption products and surface chemistry of the precatalysts (η(5)-C(5)H(5))(2)ZrR(2) (R = H, CH(3)) and [η(5)-C(5)(CH(3))(5)]Zr(CH(3))(3) adsorbed on Brønsted superacidic sulfated alumina (AlS). The latter complex is exceptionally active for benzene hydrogenation, with ~100% of the Zr sites catalytically significant as determined by kinetic poisoning experiments. The (13)C-CPMAS-NMR, DFT, and XAS data indicate formation of organozirconium cations having a largely electrostatic [η(5)-C(5)(CH(3))(5)]Zr(CH(3))(2)(+)· · · AlS(-) interaction with greatly elongated Zr · · · O(AlS) distances of ~2.35(2) Å. The catalytic benzene hydrogenation cycle is stepwise understandable by DFT, and proceeds via turnover-limiting H(2) delivery to surface [η(5)-C(5)(CH(3))(5)]ZrH(2)(benzene)(+)· · · AlS(-) species, observable by solid-state NMR and XAS.

[Experimental study of the red-bed pigment with diffuse reflectance spectroscopy].

Red pigment of continental red-bed is known originating from the fine-particle hematite in the rocks. Advance of researches on the origin of continental red-bed demonstrates that the red pigment of red-bed originated from its diagenetic but not depositional process. The high diagenetic temperature causes the dehydration of iron hydrate to form hematite, generating the red pigment. For examining the above hypothesis, the authors of this paper designed an experiment to approach the reddening process, i.e. formation of the red pigment of continental red-bed. Black ooze sampled from the Holocene sediments of the Pearl River Delta was heated in different ways. The diffuse reflectance spectroscopy (DRS) of those heated ooze samples were detected with Perkin-Elmer Lamdba 950 ultraviolet/visible/near-infrared spectrophotometer, and moreover, red-values of the samples were calculated for determining their coloring levels. Iron in black ooze sediment is predominantly in the form of goethite. Experimental results verified that initial dehydration-temperature of goethite is about 150 degrees C, either enhancing temperature or prolonging heating time is accompanied with decreasing goethite and increasing hematite, and a positive relationship exists between red-value of samples and peak-height of hematite. The experimental results strongly support the idea of thermal origin of continental red-bed.

[Reduction mammaplasty with central gland pedicle based on Würinger's horizontal septum].

OBJECTIVE: To investigate the method and efficacy of reduction mammaplasty with central gland pedicle based on Würinger' s horizontal septum in the treatment of female breast hypertrophy. METHODS: From Mar. 2009 to Sept. 2011, a series of 21 consecutive patients with mild and moderate hypermastia underwent reduction mammaplasty with central gland pedicle. Only the mammary gland located at cranial portion of septum was resected and the mammary gland located at caudal portion of septum was preserved. RESULTS: In our series, the mean resection weight per breast was (327.8 +/- 148.6) g, the mean nipple-to clavicle midpoint was 20.0 cm (range, 18.0-22.0 cm) and the mean nipple-to-sternal-notch distance was 21.0 cm (range, 19.5-22.5 cm) postoperatively. Nipple was moved upward 6.5 cm on average (range, 4.0-10.0 cm). There was no hematoma and nipple-areolar complex (NAC) necrosis. Minimal wound dehiscence occurred in one case and healed by dressing change. 17 cases were followed up for 3 months to 2 years. Satisfactory breast shape was achieved with good NAC sensibility. CONCLUSIONS: The reduction mammaplasty with central gland pedicle based on Würinger' s horizontal septum is a safe and reliable technique for mild and moderate hypermastia. Satisfactory breast contour, as well as NAC viability and sensibility, could be achieved with lower occurrence of hematoma or seroma.

CMOS buried quad p-n junction photodetector for multi-wavelength analysis.

This paper presents a buried quad p-n junction (BQJ) photodetector fabricated with a HV (high-voltage) CMOS process. Multiple buried junction photodetectors are wavelength-sensitive devices developed for spectral analysis applications where a compact integrated solution is preferred over systems involving bulk optics or a spectrometer due to physical size limitations. The BQJ device presented here is designed for chip-based biochemical analyses using simultaneous fluorescence labeling of multiple analytes such as with advanced labs-on-chip or miniaturized photonics-based biosensors. Modeling and experimental measurements of the spectral response of the device are presented. A matrix-based method for estimating individual spectral components in a compound spectrum is described. The device and analysis method are validated via a test setup using individually modulated LEDs to simulate light from 4-component fluorescence emission.

A new method of spermatic cord mobilization in herniorrhaphy.

Spermatic cord mobilization is a routine part of inguinal hernia repair, but the method of cord mobilization varies among surgeons. This study establishes an anatomic plane for spermatic cord mobilization. We studied the anatomy of the superficial cremasteric fascia in 105 male patients during herniorrhaphy for primary inguinal hernias. The mean patient age was 44.8 (18-71) years and mean body mass index was 24.1 kg/m(2) (21.5-27.1 kg/m(2)). The two layers of the superficial cremasteric fascia between the spermatic cord and the inguinal falx were incised to mobilize the cord. We found that spermatic cord mobilization during herniorrhaphy can be easily approached through an anatomic plane between the spermatic cord and the conjoined tendon with subsequent division of the superficial cremasteric fascia. None of the patients experienced any hemorrhage or nerve injury during cord mobilization. We found this method to be both safe and easy to learn.

Chronic hepatitis B virus infection and pancreatic cancer: a case-control study in southern China.

BACKGROUND: The association of hepatitis B virus (HBV) infection and pancreatic cancer is still controversial. The purpose of this study is to determine whether chronic HBV infection increases the risk. METHODS: In this case-control study, there were 1,066 patients recruited, with 533 in the study group and 533 controls, frequency-matched for age and sex. Blood samples were collected to detect hepatitis viral infection. RESULTS: Compared to 77 patients (14.4%) in the control group, 80 pancreatic cancer patients (15.0%) were seropositive for HBV surface antigen (not statistically significant, P=0.8). The prevalence of HBV e antigen was higher in study group than that of control group (P=0.03). Further analysis indicated that HBeAg was a risk factor for pancreatic cancer (OR=2.935, 95% CI: 1.048-8.220). CONCLUSIONS: In HBV endemic area of China, there appears to be no significant association between chronic HBV infection and pancreatic cancer, but the role of HBeAg needs further exploration.