[Research Photon Energy Spectrum of Medical Linear Accelerator by Monte Carlo Method].

Objective: The distribution of the photon energy spectrum in isocenter plane of the medical linear accelerator and the influence of secondary collimator on the photon energy spectrum are studied. Methods Use the BEAMnrc program to simulate the transmission of the 6 MeV electrons and photons in 5 cm×5 cm,10 cm×10 cm,15 cm×15 cm and 20 cm×20 cm fields in treatment head of the medical linear accelerator, where a phase space file was set up at the isocenter plane to record the particle information passing through this plane. The BEAMdp program is used to analyze the phase space file, in order to obtain the distribution of the photon energy spectrum in isocenter plane and the influence of secondary collimator on the photon energy spectrum. Results: By analyzing the photon energy spectrum of a medical linear accelerator with a nominal energy of 6 MV, it is found that the secondary collimator has little effect on the photon energy spectrum; different fields have different photon energy spectrum distributions; the photon energy spectrum in different central regions of the same field have the same normalized distribution. Conclusion: In the dose calculation of radiation therapy, the influence of photon energy spectrum should be carefully considered.

Feasibility of delta radiomics-based pCR prediction for rectal cancer patients treated with magnetic resonance-guided adaptive radiotherapy.

Magnetic resonance-guided adaptive radiotherapy (MRgART) represents the latest frontier in precision radiotherapy. It is distinguished from other modalities by the possibility of acquiring high-contrast soft tissue images, combined with the ability to recalculate and re-optimize the plan on the daily anatomy. The extensive database of available images offers ample scope for using disciplines such as radiomics to try to correlate features and outcomes. This study aimed to correlate the change of radiomics feature along the treatment to pathological complete response (pCR) for locally advanced rectal cancer (LARC) patients. Twenty-eight LARC patients undergoing neoadjuvant chemoradiotherapy (nCRT) with a short course (25 Gy, 5 Gy × 5f) MRgART at 1.5 Tesla MR-Linac were enrolled. The T2-weighted images acquired at each fraction, corresponding target delineation, pCR result of the surgical specimen, and clinical variables were collected. Seven families of features [First Order, Shape, Gray-level Co-occurrence Matrix (GLCM), Gray-level Dependence Matrix (GLDM), Gray-level Run Length Matrix (GLRLM), Gray-level Size Zone Matrix (GLSZM), and Neighborhood Gray Tone Difference Matrix (NGTDM)] were extracted, and delta features were calculated from the ratio of features of each successive fraction to those of the first fraction. Mann-Whitney U test and LASSO were utilized to reduce the dimension of features and select those features that are most significant to pCR. At last, the radiomics signatures were established by linear regression with the final set of features and their coefficients. A total of 581 radiomics features were extracted, and 2,324 delta features were calculated for each patient. Nineteen features and delta features, and one clinical variable (cN) were significant (p< 0.05) to pCR; seven predictive features were further selected and included in the linear regression to construct the radiomics signature significantly discriminating pCR and non-pCR groups (p< 0.05). Delta features based on MRI images acquired during a short course MRgART could potentially be used to predict treatment response in LARC patients undergoing nCRT.

The first 3D-bioprinted personalized active bone to repair bone defects: A case report.

The repair and reconstruction of bone defects are still major problems to be solved in the field of orthopedics. Meanwhile, 3D-bioprinted active bone implants may provide a new and effective solution. In this case, we used bioink prepared from the patient's autologous platelet-rich plasma (PRP) combined with polycaprolactone/ß-tricalcium phosphate (PCL/ß-TCP) composite scaffold material to print personalized PCL/ß-TCP/PRP active scaffolds layer by layer through 3D bioprinting technology. The scaffold was then applied in the patient to repair and reconstruct bone defect after tibial tumor resection. Compared with traditional bone implant materials, 3D-bioprinted personalized active bone will have significant clinical application prospects due to its advantages of biological activity, osteoinductivity, and personalized design.

Evaluation of flattening-filter-free and flattening filter dosimetric and radiobiological criteria for lung SBRT: A volume-based analysis.

Introduction: The use of volumetric modulated arc therapy (VMAT) with flattening-filter-free (FFF) beams is becoming more prevalent in lung cancer stereotactic body radiotherapy (SBRT). The aim in this study was to assess the impact of dosimetric and radiobiological differences between FFF and flattening filter (FF) beams for lung SBRT based on the target volume. Methods: A total of 198 lung stereotactic body radiation therapy treatment plans with FFF beams and FF beams were retrospectively selected for this study. For all plans, the prescribed dose was 50 Gy/5 fractions, and the dose volume histogram (DVH) for the target and organs at risk (OAR) and the normal tissue complication probability (NTCP) of the lung were recorded and compared. Moreover, monitor units (MUs), the beam on-time and the treatment time were evaluated. Results: The study was performed following the Radiation Therapy Oncology Group (RTOG) 0813 and 0915 protocols. No significant differences in D90, coverage rate (CR) or conformity index (CI) of the target were observed between FFF beams and FF beams (p>0.05). The D2, R50% and gradient index (GI) for the target improved with FFF beams compared with FF beams (p<0.05). FFF beams also significantly reduced the dose for the lung, heart, spinal cord, esophagus and NTCP of the lung (p<0.05), compared with FF beams. However, there was no significant difference in sparing of the trachea (p>0.05). The mean MUs, beam on-time and treatment time were 1871 ± 278 MUs, 3.2 ± 0.2 min and 3.9 ± 0.3 min for FFF beams, and 1890 ± 260 MUs, 4.2 ± 0.3 min and 4.8 ± 0.4 min for FF beams, respectively. Discussion: The FFF beam technique for lung SBRT with VMAT results in a better dose fall-off, better dose-sparing of OAR, lower NTCP of the lung and a shorter beam on-time compared with the FF beam technique. Additionally, the improvement in target and OAR-sparing for FFF beams was increased with increasing target volume.

Monte Carlo dosimetry of the 60Co sources of a new GZP3 HDR afterloading system.

BACKGROUND: The purpose of this work was to obtain the dosimetric parameters of the new GZP3 60Co high-dose-rate afterloading system launched by the Nuclear Power Institute of China, which is comprised of two different 60Co sources. METHODS: The Monte Carlo software Geant4 and EGSnrc were employed to derive accurate calculations of the dosimetric parameters of the new GZP3 60Co brachytherapy source in the range of 0-10 cm, following the formalism proposed by American Association of Physicists in Medicine reports TG43 and TG43U1. Results of the two Monte Carlo codes were compared to verify the accuracy of the data. The source was located in the center of a 30-cm-radius theoretical sphere water phantom. RESULTS: For channels 1 and 2 of the new GZP3 60Co afterloading system, the results of the dose-rate constant (Λ) were 1.115 cGy h-1 U-1 and 1.112 cGy h-1 U-1, and for channel 3 they were 1.116 cGy h-1 U-1 and 1.113 cGy h-1 U-1 according to the Geant4 and EGSnrc, respectively. The radial dose function in the range of 0.25-10.0 cm in a longitudinal direction was calculated, and the fitting formulas for the function were obtained. The polynomial function for the radial dose function and the anisotropy function (1D and 2D) with a [Formula: see text] of 0°-175° and an r of 0.5-10.0 cm were obtained. The curves of the radial function and the anisotropy function fitted well compared with the two Monte Carlo software. CONCLUSION: These dosimetric data sets can be used as input data for TPS calculations and quality control for the new GZP3 60Co afterloading system.

Identification of the neuropeptide gene family and feeding regulation by neuropeptide Y in Mythimna separata (Lepidoptera: Noctuidae).

Mythimna separata is a crucial agricultural pest with polyphagous characteristic. Neuropeptide signaling, especially neuropeptide Y (NPY) involved in feeding regulation, is considered as a potential pest control target. In this study, we identified 50 neuropeptides including NPY of M. separata using transcriptome sequencing. Bioinformatics analysis showed that NPY had a conserved carboxyterminal motif of RGRYamide and shared very high homology across lepidopteran insects. Spatio-temporal expression profile articulated that NPY was mainly expressed in the larval stage, and with the highest expression in larval midgut and adult alimentary canal. RNAi knockdown by the injection of dsNPY into larvae significantly inhibited food uptake and body weight, delayed developmental duration, and also caused increase of trehalose and decrease of glycogen and total lipid compared to dsGFP. This study identified nearly the entire neuropeptide gene family of M. separata and further indicated that NPY signaling pathway might played a vital role in the feeding regulation and related to energy metabolism. Our results not only laid a preliminary foundation for functional studies on neuropeptide of M. separata, but also provided a potential molecular target for future pesticide development.

Prognostic Significance of Clinicopathological Factors Influencing Overall Survival and Event-Free Survival of Patients with Cervical Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND Cervical cancer (CC) is the most frequent type of cancer among women and its poor prognosis is a main concern, while the prognostic factors for CC have still remained controversial. We conducted this systematic review and meta-analysis to identify the prognostic significance of clinicopathological factors, influencing overall survival (OS), and event-free survival (EFS) of CC patients. MATERIAL AND METHODS The electronic databases of PubMed, EmBase, and the Cochrane library were systematically searched for identification of eligible studies published until June 2021. The pooled hazard ratio (HR) with 95% confidence interval (CI) were calculated using the random-effects model. Sensitivity and subgroup analyses and assessment of publication bias were also conducted. RESULTS We selected 140 studies that involved 47 965 patients for the meta-analysis. The results revealed that age, cell type, depth of tumor invasion, the International Federation of Gynecology and Obstetrics stage, hemoglobin level, histological grade, leukocytosis, lymph node involvement, lymph-vascular space invasion, neutrophil-to-lymphocyte ratio, parametrial invasion, platelet-to-lymphocyte ratio, resection margin, squamous cell carcinoma antigen level, thrombocytosis, tumor grade, tumor size, and tumor volume were clinicopathological factors influencing OS and EFS of CC patients (P<0.05). CONCLUSIONS This study comprehensively identified the prognostic significance of clinicopathological factors, influencing OS, and EFS of CC patients. However, further large-scale prospective studies should be conducted to verify our findings and develop more accurate prognostic models for CC.

Three-dimensional printing-based personalized limb salvage and reconstruction treatment of pelvic tumors.

BACKGROUND AND OBJECTIVES: The treatment of pelvic tumors is widely recognized to be challenging. The purpose of this study was to evaluate the efficacy of personalized three-dimensional (3D) printing-based limb salvage and reconstruction treatment for pelvic tumors. METHODS: Twenty-eight pelvic tumor patients were enrolled. 3D printing lesion models and osteotomy templates were prepared for surgery planning, prosthesis design, and osteotomy assistance during surgery. 3D printing-based personalized pelvic prostheses were manufactured and used in all 28 patients. Follow-up of postoperative survival, prosthesis survival, imaging examinations, and Musculoskeletal Tumor Society (MSTS) lower limb functional scores were carried out. RESULTS: The mean follow-up period was 32.2 months, during which 16 patients had disease-free survival, 3 survived with the disease, and 9 died. The prostheses were stable, and the mean offset of the center of rotation was 5.48 mm. The prosthesis-bone interface showed good integration. For the 19 surviving patients, the mean MSTS lower limb functional score was 23.2. Postoperative complications included superficial infection in six patients and hip dislocation in three patients. CONCLUSIONS: Personalized 3D printing-based limb salvage and reconstruction was an effective treatment for pelvic tumors. Our patients achieved good early postoperative efficacy and functional recovery.

A clinical study on bone defect reconstruction and functional recovery in benign bone tumors of the lower extremity, treated by bone marrow mesenchymal stem cell rapid screening-enrichment-composite system.

BACKGROUND: With the development of medical technology, credible options for defect reconstructions after the resection of benign bone tumors of the lower extremities have become a high priority. As the current reconstructive methods commonly used in clinical practice have some flaws, new methods of reconstruction need to be explored. We aimed to prepare a new kind of bioactive scaffold for the repair of bone defects through a stem cell rapid screening-enrichment-composite technology system developed by our team. Furthermore, we aimed to investigate the curative effects of these bioactive scaffolds. METHODS: Firstly, cell count, trypan blue exclusion rate, and ALP staining were used to evaluate changes in enrichment efficiency, cell activity, and osteogenic ability before and after enrichment. Then, the scaffolds were placed under the skin of nude mice to verify their osteogenic effects in vivo. Finally, the scaffolds were used for the reconstruction of bone defects after operations for benign bone tumors in a patient's lower limb. The healing status of the defect site at 1 and 3 months was assessed by X-ray, and the Musculoskeletal Tumor Society (MSTS) score was applied to reflect the recovery of patient limb function. RESULTS: The system effectively enriched stem cells without affecting the activity and osteogenic abilities of the bone marrow mesenchymal stem cells (BMSCs). Meanwhile, the bioactive scaffolds obtained better osteogenic effects. In patients, the active scaffolds showed better bone integration and healing status, and the patients also obtained higher MSTS scores at 1 and 3 months after surgery. CONCLUSION: As a new technique, the rapid screening-enrichment-composite technology of stem cells demonstrates a better therapeutic effect in the reconstruction of bone defects after surgery for benign bone tumors of the lower extremities, which will further improve patient prognosis.

Dosimetric and delivery comparison of helical tomotherapy with dynamic jaw and fixed jaw for cervical carcinoma.

Context: Recently, the dynamic jaw mode has been introduced in our radiation oncology center second in China. Many studies showed that dynamic jaw mode in helical tomotherapy (HT) has the potential to improve organs at risk avoidance. Aim: This study aimed to evaluate the plan quality and efficiency of dynamic jaw delivery compared to the regular HT delivery mode (fixed jaw mode) for cervical carcinoma. Settings and Design: Plan quality and efficiency were compared among the fixed jaw 2.5 cm mode, the dynamic jaw 2.5 cm mode, and the dynamic jaw 5.0 cm mode. Subjects and Methods A total of 20 patients with cervical carcinoma were chosen to compare the plan quality and treatment efficiency using regular HT mode (fixed jaw 2.5 cm field width) and HT dynamic jaw mode with width 2.5 cm and 5.0 cm field width. The prescribed dose was 50.4 Gy in 28 fractions to planning target volume. Target coverage, homogeneity, conformity, sparing of organs at risk (OARs), monitor unit, and beam-on time were evaluated. Statistical Analysis Used: : The statistical significance of any difference among plans assessed the two-sided paired t-test. The statistical analysis was conducted using SPSS 19.0 software. Results: For each of the 20 patients, the plans were clinically acceptable. The target coverage and sparing of most OARs were measured using the dynamic jaw. Conclusions: Cervical carcinoma should be treated with the dynamic jaw 2.5 cm mode. Considering the risk of long treatment time, the dynamic jaw 5.0 cm mode could be an option.

A novel revision system for complex pelvic defects utilizing 3D-printed custom prosthesis.

BACKGROUND: Thus far, the hip revision surgery has been widely used and promoted, and the technology has been constantly innovated, such as tissue engineering, 3D printing prosthesis, etc. However, traditional standardized prosthesis, allograft, autograft, bone cement and reinforcing ring are still the main treatment methods in the mainstream pelvic defects classification systems for hip revision. In addition, the mainstream classification systems are still mainly focus on the peri-acetabulum, but less on the large-scale complex pelvic defects that widely affecting the regions far away from the acetabulum, which also have a significant impact on the holistic biomechanical properties of pelvis. METHODS: After integrating the design experience of custom prostheses and the understanding of biomechanical properties of pelvis, an innovative pelvic defects classification for custom revision was preliminarily proposed, and was practiced in surgeries. Some typical cases were chosen for elucidation in this study, and two observers each evaluated their CT data independently twice. Intraobserver and interobserver agreement were calculated using the kappa statistic to evaluate the reliability. The pelvis defects were classified into five types and two subtypes. The corresponding reconstruction principles, as the main basis to support the classification, were also described in detail. Prosthesis position examination and Harris hip score were utilized to evaluate the clinical outcome. RESULTS: The installed prostheses resulted in high concordance with preoperative position planning, significantly improved Harris score, low postoperative complication rate and no re-revision case. In addition, The interobserver and intraobserver agreement were both excellent. CONCLUSION: The presenting revision system for complex pelvic defects utilizing 3D-printed custom prosthesis and corresponding classification of pelvic defects can preliminarily guide patients' grouping and prosthesis design, and may potentially provide an innovative, feasible, and efficient basis for complex total hip arthroplasty (THA) revision. TRANSLATIONAL POTENTIAL STATEMENT: This study provides a novel method for prosthetic revision of peri-acetabular pelvic defects, and is expected to systematically improve the efficiency of prosthesis design and surgery in clinical practice.

Impact of positioning errors in the dosimetry of VMAT left-sided post mastectomy irradiation.

BACKGROUND: Volumetric modulated arc therapy (VMAT) adopted in post-mastectomy radiation therapy (PMRT) has the capacity to achieve highly conformal dose distributions. The research aims to evaluate the impact of positioning errors in the dosimetry of VMAT left-sided PMRT. METHODS: A total of 18 perturbations where introduced in 11 VMAT treatment plans that shifted the isocenter from its reference position of 3, 5, 10 mm in six directions. The thoracic wall and supraclavicular clinical target volumes (CTVs), the heart and the left lung dose volume histograms (DVHs) of 198 perturbed plans were calculated. The absolute differences (∆) of the mean dose (Dm) and DVH endpoints Vx and Dy (percentage volume receiving x Gy, and dose covering y% of the volume, respectively) were used to compare the dosimetry of the reference vs perturbed plans. RESULTS: Isocenter shifts in the anterior and lateral directions lead to maximum disagreement between the CTVs dosimetry of perturbed vs reference plans. Isocenter shifts of 10 mm shown a decrease of D95, D98 and Dm of 12.8, 18.0, and 2.9% respectively, for the CTVs. For 5 mm isocenter shifts, these differences decreased to 3.2, 5.2, and 0.9%, respectively, and for 3 mm shifts to 1.0, 1.7, and 0.6%, respectively. For the organs at risk (OARs), only isocenter shifts in the right, posterior and inferior directions worsen the plan dosimetry, nevertheless not negligible lung ∆ V20 of + 2.6%, and heart ∆ V25 of + 1.6% persist for 3 mm shifts. CONCLUSIONS: Inaccuracy in isocenter positioning for VMAT left-sided PMRT irradiation may impact the dosimetry of the CTVs and OARs to a different extent, depending on the directions and magnitude of the perturbation. The acquired information could be useful for planning strategies to guarantee the accuracy of the treatment delivered.

Functional Analysis of the Chemosensory Protein GmolCSP8 From the Oriental Fruit Moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae).

Chemosensory proteins (CSPs) belong to a family of small water-soluble proteins that can selectively bind and transport odorant molecules for olfactory communication in insects. To date, their definite physiological functions in olfaction remain controversial when compared with odorant binding proteins (OBPs). To investigate the functions of CSPs in the oriental fruit moth Grapholita molesta, we determined the tissue expression patterns and binding properties of the CSP, GmolCSP8. The key binding sites of GmolCSP8 with a representative ligand were evaluated using molecular flexible docking, site-directed mutagenesis and ligand-binding experiments. Multiple sequence alignment and phylogenetic analysis showed that GmolCSP8 possesses a typical conserved four cysteines motif and shares high sequence identity with some CSP members of other Lepidopteran insects. GmolCSP8 was predominantly expressed in the wings and antennae of both male and female adults and may be involve in contact chemoreception. Recombinant GmolCSP8 (rGmolCSP8) exhibited specific-binding affinities to small aliphatic alcohols (C4-12) and had the strongest binding affinity to 1-hexanol. The three-dimensional structure of GmolCSP8 was constructed using the structure of sgCSP4 as a template. Site-directed mutagenesis and ligand-binding experiments confirmed that Thr27 is the key binding site in GmolCSP8 for 1-hexanol binding, because this residue can form hydrogen bond with the oxygen atom of the hydroxyl group in 1-hexanol, and Leu30 may play an important role in binding to 1-hexanol. We found that pH significantly affected the binding affinities of rGmolCSP8 to ligand, revealing that ligand-binding and -release by this protein is related to a pH-dependent conformational transition. Based on these results, we infer that GmolCSP8 may participate in the recognition and transportation of 1-hexanol and other small aliphatic alcohols.

Transcriptomic analysis of differentially expressed genes in the oriental armyworm Mythimna separata Walker at different temperatures.

The oriental armyworm Mythimna separata Walker is a serious migratory and polyphagous pest that damages major crops and some pastures from the family Gramineae. Temperature is a crucial abiotic factor that affects its survival, development and reproduction, but the thermal responses of this moth at the molecular level are largely unknown. In this research, we sequenced the transcriptomes of oriental armyworms that were reared at three temperatures (20 °C, 25 °C and 30 °C) using an Illumina high-throughput RNA-sequencing (RNA-seq) method. We obtained 54.0 Gb of clean reads and 113,396 transcripts. From a total of 46,681 unigenes identified, 22,911 were annotated to the non-redundant (NR) database. We identified 333 downregulated and 1588 upregulated genes in 20 °C versus 25 °C, and 1096 downregulated and 875 upregulated genes at 30 °C versus 25 °C by differential expression of genes (DEGs). GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analyses revealed several functional terms related to carbohydrate metabolism, energy metabolism, and xenobiotics metabolism. DEGs involved in glycolysis, the citrate cycle, oxidative phosphorylation, and the composition of myofilaments were significantly downregulated, while most heat shock protein genes (HSPs) and genes in the ubiquitin-mediated proteasome pathway were upregulated at 30 °C. Many cytochrome P450 monooxygenase genes (CYPs) in clan 3 were upregulated at 20 °C, while two genes involved in ecdysteroid biosynthesis, CYP302A1 and CYP315A1, were upregulated at 30 °C. These data may improve the understanding of the complex molecular mechanisms involved in the thermal responses of M. separata.

Dosimetric study of GZP6 60 Co high dose rate brachytherapy source.

The purpose of this study was to obtain dosimetric parameters of GZP6 60 Co brachytherapy source number 3. The Geant4 MC code has been used to obtain the dose rate distribution following the American Association of Physicists in Medicine (AAPM) TG-43U1 dosimetric formalism. In the simulation, the source was centered in a 50 cm radius water phantom. The cylindrical ring voxels were 0.1 mm thick for r ≤ 1 cm, 0.5 mm for 1 cm < r ≤ 5 cm, and 1 mm for r > 5 cm. The kerma-dose approximation was performed for r > 0.75 cm to increase the simulation efficiency. Based on the numerical results, the dosimetric datasets were obtained. These results were compared with the available data of the similar 60 Co high dose rate sources and the detailed dosimetric characterization was discussed.

The terpene synthase gene family in Gossypium hirsutum harbors a linalool synthase GhTPS12 implicated in direct defence responses against herbivores.

Herbivore-induced terpenes have been reported to function as ecological signals in plant-insect interactions. Here, we showed that insect-induced cotton volatile blends contained 16 terpenoid compounds with a relatively high level of linalool. The high diversity of terpene production is derived from a large terpene synthase (TPS) gene family. The TPS gene family of Gossypium hirsutum and Gossypium raimondii consist of 46 and 41 members, respectively. Twelve TPS genes (GhTPS4-15) could be isolated, and protein expression in Escherichia coli revealed catalytic activity for eight GhTPS. The upregulation of the majority of these eight genes additionally supports the function of these genes in herbivore-induced volatile biosynthesis. Furthermore, transgenic Nicotiana tabacum plants overexpressing GhTPS12 were generated, which produced relatively large amounts of (3S)-linalool. In choice tests, female adults of Helicoverpa armigera laid fewer eggs on transgenic plants compared with non-transformed controls. Meanwhile, Myzus persicae preferred feeding on wild-type leaves over leaves of transgenic plants. Our findings demonstrate that transcript accumulation of multiple TPS genes is mainly responsible for the production and diversity of herbivore-induced volatile terpenes in cotton. Also, these genes might play roles in plant defence, in particular, direct defence responses against herbivores.

Monte Carlo dosimetric parameter study of a new (32)P brachytherapy source.

OBJECTIVE: Recently, a new catheter-based (32)P brachytherapy source has been developed (College of Chemistry, Sichuan University) for use in high-dose-rate afterloader. This study presents the results of the dosimetric data of the Geant4 Monte Carlo (MC) simulation toolkit for this new (32)P brachytherapy source. METHODS: The new (32)P source had dimensions of 0.50-cm length and 0.08-cm diameter and was encapsulated in teflon. In this study, we attempted to obtain dosimetric data for this new source, as required by the formalism proposed by the American Association of Physicists in Medicine reports TG60 and TG149. The source was located in a 30-cm radius theoretical sphere water phantom, and the absorbed dose of the source was calculated using MC code. RESULTS: The dosimetric data included the reference absorbed dose rate, the radial dose function in the range of 0.10-0.50 cm at a longitudinal axis, the polynomial function for the radial dose function and the anisotropy function with a θ value of 0-90° in 5° intervals and an r of 0.10-0.35 cm in 0.01-cm intervals. The radial and axial dose profiles and away-along quality assurance table are also calculated for the unsheathed (32)P source. The dose rate D(r0,θ0) at the reference point for the unsheathed (32)P source is determined to be equal to 1.2660 ± 0.0006 cGy s(-1) mCi. The radial dose function of the new (32)P source shows good agreement with the other (32)P source presented in this work with an average difference of 1.78%. CONCLUSION: Dosimetric data are provided for the new (32)P source. These data could be used in treatment-planning systems in clinical practice. ADVANCES IN KNOWLEDGE: Provided a new beta-emitting brachytherapy source that is intended for treatment of liver cancer. A dosimetric study of the unsheathed (32)P source for which no published dosimetric data existed was performed.

Identification and characterization of two general odorant binding protein genes from the oriental fruit moth, Grapholita molesta (busck).

Two novel general odorant-binding protein (GOBP) cDNAs (GmolGOBP1 and GmolGOBP2) were cloned and characterized from female antennal tissue of the oriental fruit moth, Grapholita molesta. We focused our investigation on this olfactory protein family by using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends-PCR (RACE-PCR). The full-length open reading frames of GmolGOBP1 and GmolGOBP2 were 492 and 483 nucleotides long, which encode 164 and 161 amino acid residue peptides, respectively. Protein signature analyses revealed that they each contained six conserved cysteines with an N-terminal signal sequence of 20 amino acids. The alignment of the two deduced protein sequences with other Lepidoptera GOBPs showed high sequence similarity (70-80%) with other full-length sequences from GenBank. Sequence similarity between the two GOBPs was only 48%, suggesting that the two proteins belong to different classes of lepidopteran GOBPs. RT-PCR analysis revealed that the two GOBP genes were expressed only in antennae of both sexes. Real-time PCR analysis further indicated that the transcript level of GmolGOBP1 was higher in males than in females, whereas the transcript level of GmolGOBP2 was higher in females than in males. Temporally, the two GOBP genes were expressed during the complete photoperiod (15L:9D). The highest transcript levels of GmolGOBP1 in both sexes and GmolGOBP2 in females were detected at the end of photophase and during scotophase. The expression of GmolGOBP2 in males remained at similar levels during the complete photoperiod. Based on these results, the possible physiological functions of GmolGOBPs are discussed.