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In this study, a combined process of acidic oxidation leaching and SO2 reduction was proposed to purify crude As2O3 recovered from antimony smelting arsenic-alkali residue. The effects of various process factors on crude As2O3 leaching were investigated based on the thermodynamic analysis. The results showed that the leaching efficiency of arsenic was 95.5% when crude As2O3 was leached with the mixed solution of H2SO4 and H2O2 under the conditions: the H2O2/As(III) molar ratio (n(H2O2): n(As(III))) of 0.93, leaching temperature of 75 ℃, leaching time of 90 min and liquid-solid ratio of 4:1. The kinetic study of As(V) reduction with SO2 gas showed that the reduction process conformed to the first-order gas/liquid reaction kinetics, and was controlled by both diffusion and chemical reaction with an apparent activation energy of 16.69 kJ mol−1. Arsenic could be directly recovered in the form of As2O3 from leaching solution by SO2 reduction, and the obtained product reached the standard of As2O3-1 (GB 26721-2011) after further purification. The direct recovery of arsenic was 85.8% after twice purifications for crude As2O3. In addition, no arsenic-containing wastes were produced in the purification process. Overall, this process is efficient and clean for the purification of crude As2O3.

We previously demonstrated that real-time monitoring of plasma Epstein-Barr virus DNA (EBV DNA) during chemoradiation therapy defined 4 distinct phenotypic clusters of nasopharyngeal carcinoma. In particular, the treatment-resistant group, defined as detectable EBV DNA at the end of radiation therapy, had the worst prognosis and is thought to have minimal residual disease.This is the first phase 2 trial to use a targeted agent, apatinib (an inhibitor of vascular endothelial growth factor receptor 2 tyrosine kinase), in the treatment-resistant group. Eligible patients had plasma EBV DNA0 copies/mL at the end of radiation therapy (±1 week). Patients received apatinib (500 mg, once daily) until disease progression, unacceptable toxicity, or for a maximum of 2 years. The primary endpoint was disease-free survival (DFS).Twenty-five patients were enrolled and 23 patients who received apatinib were included in the analyses. Three-year DFS was 47.8% and overall survival was 73.9%. Patients with plasma vascular endothelial growth factor-A ≤150 pg/mL at 28 days after the initiation of treatment had significantly better 3-year DFS (66.7% vs 14.3%; P = .041) and overall survival (88.9% vs 42.9%; P = .033). The most common adverse event of grade ≥3 was nasopharyngeal necrosis (26%), oral/pharyngeal pain (22%), and hand-foot syndrome (22%). Nineteen patients had serial EBV DNA data. Fourteen patients had plasma EBV DNA clearance (turn to 0), and 5 (36%) of these 14 patients had disease recurrence or death, whereas all 5 patients without EBV DNA clearance had disease recurrence or death (3-year DFS: 64.3% vs 0%; P = .001).The use of antiangiogenic agents shortly after radiation therapy might increase the risk of necrosis. This approach needs to be avoided until translational and preclinical studies reveal the underlying mechanism of interaction between radiation therapy and antiangiogenic agents.

A novel method for synthesizing poly-silicate aluminum sulfate coagulant (PSAS) using a silica-alumina sol was reported. Herein, two modalities (nSiO2/nNa2O: 1.11 and 3.27) of self-made water glasses were used as the silica source for synthesizing the sol precursor. Then, the PSAS1.11 and PSAS3.27 with different basicity were obtained by controlling the Al molar ratio of precursor to aluminum sulfate. The results showed that the PSAS1.11 coagulant prepared with low modulus water glass (LMWS, 1.11) has low turbidity and good stability. Using low modulus water glass, the effect of the Al molar ratio of precursor to aluminum sulfate on the basicity and stability of PSAS1.11 with Al/Si of 20 and the effect of the molar ratio of aluminum to silicon on the basicity and stability of PSAS1.11 were studied, respectively. Based on XRD and Fourier infrared (FTIR) characterization of the sol precursor and PSAS1.11, the synthesis mechanism of PSAS by the silica-alumina sol method was discussed. Al species distribution of PSAS1.11 was determined using the Al-Ferron timed spectrophotometric method. Moreover, the performance of PSAS1.11 coagulant was examined, regarding its efficiency towards color removal of Congo red. The results showed that PSAS1.11 coagulant with Al/Si of 20 and Al molar ratio of 1/12 exhibits excellent performance, and the color removal rate reached 98.6% at an initial pH of 11 and coagulant dosage of 40 mg L−1 (Al mg L−1). Finally, the PSAS coagulant mechanism was discussed in detail through infrared characterization, 27Al NMR, Raman, morphology and mapping of the flocs.

In this study, the removal effect of arsenic(V) was compared with different lead-containing substances, and the process of arsenic(V) removal with lead oxide was optimized. The results showed that As(V) removal efficiencies with lead powder, lead oxide, lead hydroxide and lead nitrate were 26.5%, > 99.9%, 98.5% and 96.3% at lead/arsenic(Pb/As) molar ratio of 2.12, respectively. Arsenic(V) removal with lead and its compounds was mainly based on the formation of mimetite. The removal of arsenic with lead oxide did not introduce impurity anions, and the crystallization performance and stability of the precipitate were relatively better than those of the precipitates obtained with other lead-containing substances. The crystallization performance of the precipitate was obviously improved when lead oxide was added twice. Using pH-conditioning in the process of arsenic removal, the residual lead in the solution could be removed via the co-precipitation of the hydrolysis of Pb2+ with mimetite. The highest As(V) leaching concentration of As—Pb precipitates was 0.2 mg/L at the pH of 1.9–12.3 with the leaching time of 1–48 h, and the stability of As—Pb precipitates could be improved by washing with dilute nitric acid. Lead oxide could be used as an effective reagent of arsenic removal in aqueous chloride solution.

A new method to remove arsenic from aqueous chloride solution by using lead oxide was proposed, and the effects of the lead(II)/arsenic(V) molar ratio (nPb(II):nAs(V)), initial pH of solution, initial concentrations of chloride ion (Cl−) and arsenic(V) on arsenic removal were investigated. The results showed that nPb(II):nAs(V), initial pH and initial Cl− concentration had great influence on arsenic removal. The suitable conditions of arsenic removal were initial pH of 1.8–2.4 and initial Cl− concentration of 0.52–2.00 g L−1 for 200 mg L−1 As(V) solution. Initial As(V) concentration had little influence on arsenic removal when the appropriate nAs(V):n Cl − was controlled in the solution at nPb(II):nAs(V) of 1.52. Based on these conditions, As(V) removal efficiency reached up to 99.99% and As(V) concentration decreased from 200 mg L−1 to less than 0.01 mg L−1 at initial pH of 1.8 with nPb(II):nAs(V) of 2.12. Various characterizations confirm that the formed precipitate was mimetite (Pb5(AsO4)3Cl) and had better thermal stability within 500 °C. For the prevalent problem of lead dissolution by forming mimetite, Pb residual concentration reduced from 337.6 to 0.07 mg L−1 using sodium sulfide in the solution after arsenic removal. Therefore, lead oxide could be used as an effective reagent of arsenic removal to remove As(V) from aqueous chloride solution.

Purpose: The benefits of additional use of nimotuzumab (NTZ) in the treatment of locoregionally advanced nasopharyngeal carcinoma (LA-NPC) is largely unclear. We aim to compare LA-NPC treatment outcomes in patients that received CCRT with nimotuzumab (NTZ) to patients that received CCRT only. Materials and Methods: Between October 2009 and January 2012, 31 previously untreated and newly diagnosed LA-NPC patients were administered CCRT (3 cycles of 100 mg/m2 cisplatin every third week with intensity-modulated radiotherapy) plus NTZ according to an IRB-approved institutional research protocol. A well-balanced cohort of 62 patients who received CCRT alone was created by matching each patient who received CCRT plus NTZ via propensity-matched analysis in a 2:1 ratio. Results: Compared with CCRT only, CCRT plus NTZ was significantly associated with superior overall survival (5-year OS; 96.8% vs. 82.3%; P = 0.001), superior distant metastasis-free survival (5-year DMFS; 90.3% vs. 80.6%, P = 0.012) and superior progression-free survival (5-year PFS; 83.9% vs. 71.0%, P = 0.006). In multivariate analysis, the inclusion of NTZ to CCRT was confirmed to be a favorable factor for OS (HR, 0.31; 95% CI, 0.02–0.71; P = 0.027), DMFS (HR, 0.45; 95% CI, 0.13–0.77; P = 0.034), and PFS (HR, 0.38; 95% CI, 0.11–0.89; P = 0.041). In addition, no significant differences in hematology parameters, dermatitis, nausea, vomiting, xerostomia, nephrotoxicity or neurotoxicity were found between the two arms (all P > 0.05). Conclusion: The inclusion of NTZ to CCRT is more effective for long-term survival among LA-NPC patients than CCRT only.

The effect of PEG dispersant on the magnetic separation of magnetite (Fe3O4) synthesized from ferrous sulfate solution via co-precipitation method with calcium hydroxide as the precipitant was investigated. The results indicated that a PEG dispersant could significantly affect Fe3O4 recovery. Adding PEG during the preparation of Fe3O4 was unfavorable for Fe3O4 recovery. When the PEG-6000 concentration was increased from 0 to 8 g/L, the iron grade and median particle size of the Fe3O4 product decreased from 65.58% and 2.35 μm to 57.79% and 1.35 μm, respectively. However, adding PEG during the wet milling of the mixed product promoted the subsequent recovery of Fe3O4. When the amount of PEG-200 increased from 0% to 4% of the powder mass, the grade of iron in the Fe3O4 product increased from 65.58% to 68.32%. While the relative molecular mass of PEG at an amount of 4% of the powder mass increased from 200 to 20000, the grade of iron was reduced from 68.32% to 66.70%.

Background: In practice, the dose perturbation effect of head and neck immobilization devices is often overlooked in intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC). Purpose of this study is to verify and analyze the dosimetric effect of head and neck immobilization devices on NPC multi-field IMRT. Methods: Ten patients with nasopharyngeal carcinoma were randomly selected. Two sets of body contours were established for each patient. One set of body contours did not contain the immobilization device, and the other contour set included the immobilization device. For each patient, dose calculations were conducted for the two sets of contours using the same 9-field IMRT plan, which were recorded as Plan- and Plan+. The dose difference caused by the head and neck immobilization devices was assessed by comparing the dose-volume histogram (DVH) parameter results and by plan subtraction. The gafchromic EBT3 film and anthropomorphic phantom were used to verify the calculated doses. Results: The target coverage and average dose of Plan+ were lower than those of Plan- : the prescription dose coverage rates for PTVnx, PTVnd, PTV1 and PTV2 decreased by 2.4%, 9.9%, 1.5%, and 3.6%, respectively, and the mean doses were reduced by 0.9%, 1.9%, 1.1%, and 1.5%, respectively. Doses in the organs at risk showed no significant differences or slight reductions (the maximum reduction in mean dose was 1.7%). From the EBT3 measurements, the skin dose on the posterior neck was increased by approximately 53%. Conclusion: The attenuation and bolus effects of the head and neck immobilization device reduce dose coverage rate and average dose of the planning target volumes in nasopharyngeal carcinoma and lead to an increase in the skin dose. During treatment planning and dose calculation, the immobilization device should be included within body contour to account for the dose attenuation and skin dose increment.

Magnetite concentrate was recovered from ferrous sulphate by co-precipitation and magnetic separation. In co-precipitation process, the effects of reaction conditions on iron recovery were studied, and the optimal reaction parameters are proposed as follows: n(CaO)/n(Fe2+) 1.4:1, reaction temperature 80 °C, ferrous ion concentration 0.4 mol/L, and the final mole ratio of Fe3+ to Fe2+ in the reaction solution 1.9–2.1. In magnetic separation process, the effects of milling time and magnetic induction intensity on iron recovery were investigated. Wet milling played an important part in breaking the encapsulated magnetic phases. The results showed that the mixed product was wet-milled for 20 min before magnetic separation, the grade and recovery rate of iron in magnetite concentrate were increased from 51.41% and 84.15% to 62.05% and 85.35%, respectively.

Proper utilization of the FeSO4·7H2O waste slag generated from TiO2 industry is an urgent need, and Fe3O4 particles are currently being widely used in the wastewater flocculation field. In this work, magnetite was recovered from ferrous sulphate by a novel co-precipitation method with calcium hydroxide as the precipitant. Under optimum conditions, the obtained spherical magnetite particles are well crystallized with a Fe3O4 purity of 88.78%, but apt to aggregate with a median particle size of 1.83 μm. Magnetic measurement reveals the obtained Fe3O4 particles are soft magnetic with a saturation magnetization of 81.73 A·m2/kg. In addition, a highly crystallized gypsum co-product is obtained in blocky or irregular shape. Predictably, this study would provide additional opportunities for future application of low-cost Fe3O4 particles in water treatment field.

The present study was conducted to elucidate the influence of impurities in waste ferrous sulfate on its recovery of magnetite. Ferrous sulfate solution was purified by the addition of NaOH solution to precipitate impurities, and magnetite was recovered from ferrous sulfate solution without and with purification pretreatment. Calcium hydroxide was added to the solution of ferrous sulfate as a precipitator. A mixed product of magnetite and gypsum was subsequently obtained by air oxidation and heating. Wet-milling was performed prior to magnetic separation to recover magnetite from the mixed products. The results show that with the purification pretreatment, the grade of iron in magnetite concentrate increased from 62.05% to 65.58% and the recovery rate of iron decreased from 85.35% to 80.35%. The purification pretreatment reduced the conglutination between magnetite and gypsum, which favors their subsequent magnetic separation. In summary, a higher-grade magnetite with a better crystallinity and a larger particle size of 2.35 μm was obtained with the purification pretreatment.

For the comprehensive utilization of antimony smelting arsenic-alkali residue, there are some problems such as the incomplete separation and low recoveries of arsenic and alkali, and the formation of arsenic-alkali mixed salts with secondary pollution. In order to solve these problems, the leaching solution of arsenic-alkali residue (arsenic-alkali solution) was used as a raw material in this study, and a novel process of twice alkali recovery with CO2, deep alkali removal with H2SO4, As(V) reduction with SO2 and evaporation concentration to recover arsenic was proposed to dispose of the arsenic-alkali solution. The total recovery of alkali was 87.8% by twice alkali recovery from the arsenic-alkali solution. After washing and thermal decomposition of crude NaHCO3, the obtained Na2CO3 product can be used as the reagent of arsenic removal in the refining process of crude antimony. In the process of deep alkali removal, compared with the direct treatment, the consumption of H2SO4 after twice alkali recovery was markedly reduced from the arsenic-alkali solution, and also no mirabilite was precipitated. The total recovery of arsenic was 80.6% in the process of arsenic recovery, and the purity of As2O3 in arsenic trioxide product reached 95.2% after washing, which meets the third grade standard of arsenic trioxide (GB 26721–2011). This process realizes the efficient separation and recovery of arsenic and alkali from the arsenic-alkali solution, and also no arsenic-alkali mixed salts are produced.

Arsenic-alkali residue is a hazardous waste produced by the refining process of crude antimony in antimony smelting, and contains highly toxic sodium arsenate and a large number of residual alkali. In this study, aiming at the problems of the low recoveries and incomplete separation of arsenic and alkali, the secondary pollution of arsenic-alkali mixed salts and the insufficient utilization of valuable resources in the treatment process of arsenic-alkali residue, a new process of antimony enrichment with water leaching, twice alkali recovery with CO2, selenium recovery with acidification and arsenic recovery with SO2 reduction and evaporation concentration was proposed to dispose arsenic-alkali residue. The results showed that the leaching efficiencies of Sb, As, Se and alkali in arsenic-alkali residue were 1.8, 98.4, 97.9 and 100% by hot water leaching, respectively. Alkali was recovered with CO2 from arsenic-alkali solution and the direct recovery was 87.8%. In addition, the purity of Na2CO3 product was higher than 90% and As content in product was controlled below 0.2%. Deep alkali removal and efficient selenium recovery were achieved by acidification from the solution after alkali recovery, the direct recovery of Se was 80.6%, and the purity of crude selenium was 81.7%. Arsenic was recovered from the solution after selenium removal and the direct recovery was 79.4%, and the quality of As2O3 product reached the third grade standard of arsenic trioxide (GB 26721-2011). This process realizes the efficient recovery of alkali, selenium and arsenic in arsenic-alkali residue, and also does not produce arsenic-alkali mixed salts and wastewater.

The original version of this article [1] unfortunately contained a mistake.

Differentiation of preadipocytes into adipocytes and the formation of the subsequent adipose tissue are critical for mammalian growth and development. The molecular mechanism relating to preadipocyte differentiation and adipogenesis from the perspective of miRNAs is not yet completely understood. Here we investigated whether miR-183 functioned in the differentiation process. Both gain-of-function and loss-of-function assays demonstrated that miR-183 positively regulated 3T3-L1 differentiation by enhancing the expression of adipogenic marker genes such as CCAAT/enhancer binding protein α (C/EBPα), peroxisome proliferator-activated receptor γ (PPARγ), adiponectin and fatty acid synthase (FAS), as well as the triglyceride content and accumulation of lipid droplets. Meanwhile, low-density lipoprotein receptor-related protein 6 (LRP6) was known to impair the canonical Wnt/β-catenin signaling pathway and thereafter reduce c-myc and nuclear β-catenin protein. We showed that the inhibition of LRP6 by siRNA promoted 3T3-L1 adipogenic differentiation and adipogenesis. Further analysis showed that mouse miR-183 gene had its own transcription unit containing CpG islands, transcription start site (TSS), coding sequence (CDS) and polyA signal within the flanking sequences 2500 nt upstream and downstream of mouse miR-183 in genome. The core promoter of miR-183 gene was identified and transcription factor GATA3 (GATA binding protein 3) significantly inhibited the expression of mature miR-183 by binding to its core promoter in vivo, as indicated by the chromatin immunoprecipitation (ChIP) assay. These results suggest that miR-183, though negatively regulated by transcription factor GATA3, enhances 3T3-L1 preadipocyte differentiation and adipogenesis through the inhibition of the canonical Wnt/β-catenin signaling pathway by targeting LRP6.

Cu and As were separated and recovered from copper electrolyte by multiple stage electrowinning, reduction with SO 2 and evaporative crystallization. Experimental results showed that when the current density was 200 A/m 2 , the electrolyte temperature was 55 °C, the electrolyte circulation rate was about 10 mL/min and the final Cu concentration was higher than 25.88 g/L, the pure copper cathode was recovered. By adjusting the current density to 100 A/m 2 and the electrolyte temperature to 65 °C, the removal rate of As was 18.25% when the Cu concentration decreased from 24.69 g/L to 0.42 g/L. After As(V) in Cu-depleted electrolyte was fully reduced to As(III) by SO 2 , the resultant solution was subjected to evaporative crystallization, then As 2 O 3 was produced, and the recovery rate of As was 59.76%. The cathodic polarization curves demonstrated that both Cu 2+ concentration and As(V) affect the limiting current of Cu 2+ deposition.

The oxidation of arsenic from As(III) to As(V) during copper electrorefining was studied. Experimental results showed that during copper electrorefining, the precipitation of impurities As, Sb and Bi in the electrolyte has strong relation with the oxidation. When As(III) and As T were 5.00 g/L and 10.00 g/L respectively in the initial electrolyte, after copper electrolysis carried out with current density 235 A/m 2 at 65 °C for 168 h, the concentrations of Sb and Bi were decreased 35.0% and 18.2% respectively, while without As(III) in the initial electrolyte, under the same conditions, the concentrations of Sb and Bi weren't decreased but increased 12.5% and 9.1% respectively. It was found that the oxidation of arsenic from As(III) to As(V) plays an important role in the precipitation of impurities As, Sb and Bi in copper electrolyte as well, and the oxidation is applicable to the pseudo-first order kinetic model.

Cu, As, Sb and Bi in copper electrolyte could be efficiently removed by reducing with SO2 followed by evaporative crystallization. As2O3 and CuSO4·5H2O were obtained after crystallized product was treated by dissolution, oxidation, neutralization, sedimentation, filtration and evaporative crystallization. The removal rates of Cu, As, Sb and Bi are 87.1%, 83.9%, 21.0% and 84.7%, respectively, when As (V) in copper electrolyte is fully reduced to As (III) by SO2, and the H2SO4 in concentrated copper electrolyte is 645 g/L. The removal rate of As is 92.81% when 65 g crystallized product is dissolved in 200 mL water at 30°C. The CuSO4·5H2O content is 98.8% when the filtrate is purified under the conditions that n(Fe):n(As) is 1.2, the dosage of H2O2 is 19 times the stoichiometric needed, temperature is 45°C, time is 40 min, pH is 3.7, and then is evaporation crystallized.

The influences of temperature, H 2 SO 4 concentration, CuSO 4 concentration, reaction time and SO 2 flow rate on the reduction of arsenic(V) with SO 2 were studied and the deposition behavior of arsenic (III) under the effect of concentration and co-crystallization was investigated in copper electrolyte. The results indicate that reduction rate of arsenic (V) decreases with increasing temperature and H 2 SO 4 concentration, but increases with increasing SO 2 flow rate and reaction time, and it can reach 92% under appropriate conditions that reaction temperature is 65°C, H 2 SO 4 concentration is 203 g/L, CuSO 4 concentration is 80 g/L, reaction time is 2 h and SO 2 gas flow rate is 200 mL/min. To remove arsenic in the copper electrolyte, arsenic (V) is reduced to trivalence under the appropriate conditions, the copper electrolyte is concentrated till H 2 SO 4 concentration reaches 645 g/L, and then the removal rates of As, Cu, Sb and Bi reach 83.9%, 87.1%, 21.0% and 84.7%. The XRD analysis shows that crystallized product obtained contains As 2 O 3 and CuSO 4 ·5H 2 O.

This study is to identify significant dosimetric parameters for ear disorders in nasopharyngeal carcinoma (NPC) patients treated with intensity modulated therapy only. Ninety-seven patients with NPC were retrospectively reviewed. Organs at risk (OARs) in the auditory apparatus were contoured. Dose–volume histogram parameters were generated for the Eustachian tube (ET), tympanic cavity (TC), mastoid air cells, vestibular apparatus, cochlea and internal auditory canal (IAC). Ear disorders were rated 0 (none), 1 (mild) or 2 (severe) by a clinician blinded to radiation doses; Grade 2 ear disorders was the study end-point. Multivariate analysis revealed ET.D30 (dose to 30% of ET volume) >52.75 Gy and M.D0.5CC (dose to 0.5 ml of mastoid volume) >41.04 Gy (OR = 3.77, P = 0.012 and OR = 1.27, P = 0.033, respectively) were associated with Grade 2 ear disorders. Our results demonstrated that post-irradiation ear disorders remain a common late toxicity in NPC after IMRT. ET.D30 and M.D0.5CC should be considered during IMRT treatment plan optimization, review and approval.

Background and Objective: Cone-beam computed tomography (CBCT) has been widely used in radiation treatment positioning as so called image guided radiation therapy (IGRT) technique. It is impossible to correct all local position error by doing global IGRT positioning since deformation always happens in the patient and the positioning shifts relies on the image registration technique used in the image guidance. This study evaluated and analyzed the regional accuracy of CBCT guided positioning used different image registration strategy with a comprehensive scoring method to provide a reasonable guidance for clinic application of cancer IGRT.

The genetic polymorphisms of Atrn gene, which were from 174 F0-F5 Danish resource family pigs (DRF) that has undergone five successive generations of inbreeding and 129 F9 Hunan yellow pigs (HY) that were developed by crossbreeding, were tested by PCR-RFLP method, and the effects to carcass and growth traits were also analyzed. The results showed that: (1) Three genotypes of AA, AB, BB were detected by Taq I-RFLP in the two pig breeds, and highly significant differences (P0.01) in genotype frequencies were found between the two breeds; (2) Based on the linkage analysis of resource family pigs using CRI-MAP V2.4 software, Atrn gene loci in DRF was found to be linked with SW1031 loci on chromosome 17, the recombination frequency and LOD score for Atrn gene were 0.21 and 3.19 respectively; (3) With the least square analysis of multi-variable model, the significant differences among Atrn genotypes were found in ADSG and ABF traits in DRF and also in ADG, ABF and LMP traits in HY (P0.05 or P0.01), BB genotype pigs were superior to AA or AB genotype pigs. Based on the above mentioned results, B gene has favorable effects in important economic traits, and thus selection to BB genotype will get favorable effects in important economic traits. This will provide theory basis for Atrn gene being regarded as a candidate gene in pig carcass and growth traits.

A search for chromosome 13 QTL was carried out in a pig family of complex pedigree. The results indicated that a significant QTL on chromosome 13 was segregating in pig family. The QTL significantly affected body weight and average daily gain (P0.05), but the effect on backfat thickness was not significant (P0.05). Interval mapping localized this QTL between SW1898 and SW398. The estimated linkage position of this QTL was 75.2 cM. The QTL variance estimated at the marker interval was 0.9037 for the body weight and 0.0010 for average daily gain, respectively. This was the region which flanked the PIT1 gene, an essential transcriptional regulatory factor of growth hormone, prolactin and thyrotropin beta subunit. The present result confirmed a previous suggestion of a QTL for early growth traits at the estimated PIT1 position, and further implied that the effect of PIT1 genes on growth and body weight remained for the whole period of individual growth and development. Aditional evidence was also found which suggested a backfat QTL on chromosome 13, at a location approximately 28.3-63.4 cM apart from the one for body weight and growth, but the level of significance was not consistent in different generations.