Toxicology assessment of deep-sea mining impacts on Gigantidas platifrons: A comparative in situ and laboratory metal exposure study.

Deep-sea toxicology is essential for deep-sea environmental impact assessment. Yet most toxicology experiments are conducted solely in laboratory settings, overlooking the complexities of the deep-sea environment. Here we carried out metal exposure experiments in both the laboratory and in situ, to compare and evaluate the response patterns of Gigantidas platifrons to metal exposure (copper [Cu] or cadmium [Cd] at 100 µg/L for 48 h). Metal concentrations, traditional biochemical parameters, and fatty acid composition were assessed in deep-sea mussel gills. The results revealed significant metal accumulation in deep-sea mussel gills in both laboratory and in situ experiments. Metal exposure could induce oxidative stress, neurotoxicity, an immune response, altered energy metabolism, and changes to fatty acid composition in mussel gills. Interestingly, the metal accumulating capability, biochemical response patterns, and fatty acid composition each varied under differing experimental systems. In the laboratory setting, Cd-exposed mussels exhibited a higher value for integrated biomarker response (IBR) while in situ the Cu-exposed mussels instead displayed a higher IBR value. This study emphasizes the importance of performing deep-sea toxicology experiments in situ and contributes valuable data to a standardized workflow for deep-sea toxicology assessment.

Vaccine events raising public concern and associated immunization program policy and practice changes, China, 2005-2021.

INTRODUCTION: Several vaccine events causing public concern have occurred in China that were investigated and responded to by the central government. We describe causes, influences, and policy or practice changes associated with vaccine events that occurred between 2005 and 2021. We make recommendations to foster resilience in China's Expanded Program of Immunization (EPI) system and vaccination enterprises and to sustain vaccine and program confidence. METHODS: Our study included all vaccine events since 2005 that were investigated and responded to by the central government of China. We verified mainstream and social media visibility of the events through Internet search. We extracted event times, causes, investigation processes, results, actions, and policy or practice regulation changes from official reports of government meetings and from official websites with media briefings. RESULTS: Seven vaccine events were identified, each of which caused more than 100,000 mainstream or social media reports nationally or nationally and internationally. The events ranged in magnitude from 145 children receiving out-of-date oral poliovirus vaccine to a measles supplementary immunization activity involving 103 million children. Few, if any, children were directly harmed by vaccines in the events. Government responded to each event with program or policy changes, and in one case, with legislation. Responses affected the conduct of campaigns and supplementary immunization activities, use of schools as vaccination venues, financial incentives for vaccinating with non-program vaccines, vaccine procurement and distribution, and program policy making. The most fundamental response was enacting the country's first vaccine law, the 2019 Vaccine Administration Law, which guides virtually all aspects of vaccination work, from vaccine development through regulation, program implementation, and safety and impact monitoring. CONCLUSIONS: All seven events generated substantial national and international mainstream and social media criticism and discussion, most commonly expressed through concerns of vaccine safety or vaccine effectiveness. Most had temporally associated temporary declines in vaccine confidence and coverage, jeopardizing decades of vaccination effort. The central government responded to each event by attempting to address root causes. Faithful implementation of the Vaccine Administration Law is fundamental to program strengthening and sustaining confidence of families, stakeholders, and government in vaccines and immunization in China.

Critical assessment of DNA adenine methylation in eukaryotes using quantitative deconvolution.

The discovery of N6-methyldeoxyadenine (6mA) across eukaryotes led to a search for additional epigenetic mechanisms. However, some studies have highlighted confounding factors that challenge the prevalence of 6mA in eukaryotes. We developed a metagenomic method to quantitatively deconvolve 6mA events from a genomic DNA sample into species of interest, genomic regions, and sources of contamination. Applying this method, we observed high-resolution 6mA deposition in two protozoa. We found that commensal or soil bacteria explained the vast majority of 6mA in insect and plant samples. We found no evidence of high abundance of 6mA in Drosophila, Arabidopsis, or humans. Plasmids used for genetic manipulation, even those from Dam methyltransferase mutant Escherichia coli, could carry abundant 6mA, confounding the evaluation of candidate 6mA methyltransferases and demethylases. On the basis of this work, we advocate for a reassessment of 6mA in eukaryotes.

Assessment of 9-OH- and 7,8-diol-benzo[a]pyrene in Blood as Potent Markers of Cognitive Impairment Related to benzo[a]pyrene Exposure: An Animal Model Study.

The potent neurotoxicity of benzo[a]pyrene (B[a]P) has been suggested to be a susceptibility factor accelerating the onset of brain tumours and the emergence of neurobehavioural disturbances. B[a]P has been shown to be neurotoxic, acting directly on both the central and peripheral nervous systems, as well as indirectly via peripheral organs like liver and gut. By using a realistic B[a]P exposure scenario (0.02-200 mg/kg/day, 10 days) in mice, we elucidated brain-specific B[a]P metabolism and at identified hydroxylated B[a]P metabolites in serum which could be used as markers of cognitive impairment. Repeated oral administration of B[a]P led to, at the doses of 20 and 200 mg/kg/day, significant overexpression of Cyp1a1/Cyp1b1 in 2 out of the 3 brain regions considered, thereby suggesting the ability of the brain to metabolize B[a]P itself. At the same doses, mice exhibited a reduction in anxiety in both the elevated plus maze and the hole board apparatus. Concomitantly, B[a]P triggered dose-dependent changes in Nmda subunit expression (Nr1 and Nr2a/Nr2b) in areas involved in cognition. We detected 9-OH-B[a]P and 7,8-diol-B[a]P in serum at the level for which cognitive impairment was observed. We suggest that these metabolites may, in the future be exploited as potent biomarkers of B[a]P-induced cognitive impairments.

Characterization and phylogenetic significance of the complete chloroplast genome of Camellia Kissii, an economic crop for producing oil.

Camellia kissii is cultivated for a long time as an oil crop for edible and industrial oils, and has the functions of high oil production rate and unique health care. The complete chloroplast (cp) genome sequence of C. kissii is 156,961 bp in length with GC content of 39.29%. It presents a quadrate structure, including a large single-copy (LSC) region (86,640 bp), a small single-copy (SSC) region (18,399 bp), and a pair of inverted repeats (IRs) (25,961 bp). Meanwhile, 15 complete chloroplast genome of Camellia was aligned to explore the phylogenetic significance of Camellia. And the genetic relationship between Camellia kissii and Camellia huana was found to be closest.

A Comparison of Monte Carlo Methods for Computing Marginal Likelihoods of Item Response Theory Models.

Nowadays, Bayesian methods are routinely used for estimating parameters of item response theory (IRT) models. However, the marginal likelihoods are still rarely used for comparing IRT models due to their complexity and a relatively high dimension of the model parameters. In this paper, we review Monte Carlo (MC) methods developed in the literature in recent years and provide a detailed development of how these methods are applied to the IRT models. In particular, we focus on the "best possible" implementation of these MC methods for the IRT models. These MC methods are used to compute the marginal likelihoods under the one-parameter IRT model with the logistic link (1PL model) and the two-parameter logistic IRT model (2PL model) for a real English Examination dataset. We further use the widely applicable information criterion (WAIC) and deviance information criterion (DIC) to compare the 1PL model and the 2PL model. The 2PL model is favored by all of these three Bayesian model comparison criteria for the English Examination data.

Factors influencing the routine immunization status of children aged 2-3 years in China.

OBJECTIVES: To examine the factors associated with the routine immunization status of children aged 2-3 years in China for gaining a better understanding of the Expanded Program on Immunization and to provide evidence for formulating specific strategies to guide the allocation of health resources. METHODS: We analyzed data from 45095 children aged 2-3 years in the 2013 National Immunization Coverage Survey to identify the sociodemographic and provider-associated factors affecting the full immunization status of children. Univariate and multiple logistic regression analyses were performed. RESULTS: The immunization rate for children aged 2-3 years ranged from 95.9% (diphtheria and tetanus toxoid with pertussis vaccine, 4th dose) to 99.5% (Japanese encephalitis vaccine, 1st dose) and was 93.1% for full immunization. In terms of sociodemographic factors, male children [adjusted OR (AOR): 1.115; 95% confidence interval(CI):1.016-1.222], minority children (AOR: 1.632; 95% CI: 1.457-1.828), children of fathers with less than high school education (AOR: 1.577; 95% CI: 1.195-2.081), those born at home (AOR: 4.655; 95% CI: 3.771-5.746), those who immigrated from an adjacent county (AOR: 2.006; 95% CI: 1.581-2.546), and those living in urban-rural fringe areas (AOR: 1.807; 95% CI: 1.475-2.214) or mountainous areas (AOR: 1.615; 95% CI: 1.437-1.814) had significantly increased odds of not being fully immunized. In terms of provider-associated factors, administration of vaccines at home (AOR: 2.311; 95% CI: 1.316-4.059), household reminders (AOR: 2.292; 95% CI: 1.884-2.789), and travel time to vaccination providers of >40 minutes (AOR: 1.622; 95% CI: 1.309-2.010) were negatively associated with immunization rates. In addition, compared to 3-year-old years, 2-year-old children (AOR: 1.201; 95% CI: 1.094-1.318) were less likely to be fully immunized. CONCLUSIONS: All included factors except maternal education level and distance from home to vaccination providers significantly affected immunization rates. Appropriate reminders and accessibility of immunization services played key roles in improving the immunization status. More attention to high-risk groups identified in this study may reduce the disparities in routine childhood immunization in China.

A potential efflux boron transporter gene GsBOR2, positively regulates Arabidopsis bicarbonate tolerance.

Soil alkalization severely restricts agricultural production and economic development worldwide, this problem is far more serious in Songnen Plain, the largest commodity grain base of China. However, little research has been done concerning the mechanisms of plant responses to alkaline stress to date. In this study, we isolated an alkali inducible gene GsBOR2 from Glycine soja on the basis of RNA seq data. GsBOR2 sh high protein sequence similarity with the known boron transporters in other species. The expression of GsBOR2 was highly up-regulated by 50 mM NaHCO3 treatment and displayed tissue specificity. We then generated the transgenic Arabidopsis overexpressing GsBOR2 and found that the transgenic lines exhibited enhanced alkaline tolerance compared to wild type plants, as illustrated by longer roots and greater shoot biomass. Moreover, GsBOR2 overexpression was also capable of increasing plant resistance to KHCO3 treatment but not to high-pH stress. Functional complementation of Scbor1 mutant yeasts suggested that GsBOR2 could likely mediate the efflux of boron from cells. Taken together, the alkali responsive gene GsBOR2 is a positive regulator of plant bicarbonate tolerance.

Routine immunization services costs and financing in China, 2015.

OBJECTIVE: To estimate the costs of routine immunization (RI) services in China in 2015, to provide objective data relevant to investment in the Expanded Program on Immunization, and to contribute to global data on costing and financing of RI. METHODS: The study was conducted between January and March 2016. We selected 276 villages, 138 townships, 46 counties, and 40 prefectures from 15 provinces as investigation sites at random, stratified by eastern, middle, and western regions. Direct cost items included vaccines, personnel, cold chain, surveillance, communication, training, and supervision at the national, provincial, prefecture, county, township, and village levels. We obtained financial data from governmental and external sources. Indirect costs of RI included parents' transportation costs and productivity lost due to taking their children for vaccination. RESULTS: Total direct costs were $92.42 for each child fully immunized ($4.20/dose), which equates to $1529.55 million per birth cohort. RI costs were higher in the eastern region than in the western region, and higher than that of the central region. Vaccination coverage was positively associated with direct routine immunization costs. The cost of the recommended vaccines was $19.08/child and vaccine only accounted for 20.64% of total costs. Operational cost, including surveillance, communication, training and supervision, was $217.31/child, accounting for 14.21% of total cost. The indirect cost per child was $72.86; the total indirect cost was $1205.83 million for the birth cohort. Government investment in RI accounted for about 70% of total costs. Revenue from sales of private-sector vaccine supported the remaining 30% of RI costs. CONCLUSIONS: While government financing has increased, some operating costs continue to be provided from revenue generated by sales of Category 2 (private-sector) vaccines to families. China could benefit from bringing new and underutilized vaccines into the EPI system based on evidence that includes routine immunization vaccine and operations costs.

[Effect of a clinical pathway in patients with Crohn's disease complicated with intestinal obstruction].

OBJECTIVE: To evaluate the effect of a clinical pathway for Crohn disease (CD) complicated with intestinal obstruction. METHODS: CD patients complicated with intestinal obstruction in Inflammatory Bowel Disease(IBD) Center of Jinling Hospital were enrolled. One hundred and nineteen CD patients from March 2014 to September 2015 received treatment with the clinical pathway (CP), which was developed based on medical evidence and experience of the IBD center in February 2014, as CP group. The other 108 CD patients from September 2012 to February 2014 received treatment according to the management strategy made by individual attending physician as non-CP group. Rate of operation, rate of stoma, morbidity of surgical complications, hospital stay, hospital cost, and 6-month unplanned re-admission were compared between two groups. RESULTS: The baseline data were similar between the two group (all P > 0.05). No significant differences were noted between these the two groups in terms of rate of operation (73.9% vs. 77.8%, P = 0.605), rate of stoma (15.9% vs. 25.0%, P = 0.197), and morbidity of surgical complications (23.9% vs. 27.4%, P = 0.724). However, the mean postoperative hospital stay was shorter (10.9 d vs. 13.2 d, P = 0.000), the mean hospital cost was less (78 325 Yuan vs. 85 310 Yuan, P = 0.031) and the rate of 6-month unplanned re-admission was lower(3.4% vs. 11.1%, P = 0.035) in CP group. CONCLUSION: Treatment based on this CP for CD patients complicated with intestinal obstruction can reduce the rate of 6-month unplanned re-admission, shorten the postoperative hospital stay and decrease the hospital cost in patients requiring surgery.

Assessment of Suitable Reference Genes for Quantitative Gene Expression Studies in Melon Fruits.

Melon (Cucumis melo L.) is an attractive model plant for investigating fruit development because of its morphological, physiological, and biochemical diversity. Quantification of gene expression by quantitative reverse transcription polymerase chain reaction (qRT-PCR) with stably expressed reference genes for normalization can effectively elucidate the biological functions of genes that regulate fruit development. However, the reference genes for data normalization in melon fruits have not yet been systematically validated. This study aims to assess the suitability of 20 genes for their potential use as reference genes in melon fruits. Expression variations of these genes were measured in 24 samples that represented different developmental stages of fertilized and parthenocarpic melon fruits by qRT-PCR analysis. GeNorm identified ribosomal protein L (CmRPL) and cytosolic ribosomal protein S15 (CmRPS15) as the best pair of reference genes, and as many as five genes including CmRPL, CmRPS15, TIP41-like family protein (CmTIP41), cyclophilin ROC7 (CmCYP7), and ADP ribosylation factor 1 (CmADP) were required for more reliable normalization. NormFinder ranked CmRPS15 as the best single reference gene, and RAN GTPase gene family (CmRAN) and TATA-box binding protein (CmTBP2) as the best combination of reference genes in melon fruits. Their effectiveness was further validated by parallel analyses on the activities of soluble acid invertase and sucrose phosphate synthase, and expression profiles of their respective encoding genes CmAIN2 and CmSPS1, as well as sucrose contents during melon fruit ripening. The validated reference genes will help to improve the accuracy of gene expression studies in melon fruits.

Assessment of endoscopic treatment for quadrigeminal cistern arachnoid cysts: A 7-year experience with 28 cases.

BACKGROUND: Quadrigeminal cistern arachnoid cysts (QACs) are difficult to treat because of their deep location and the presence of nervous and vascular structures of the pineal-quadrigeminal region. There are several surgical procedures available for QACs, including craniotomy and cyst excision or fenestration, ventriculoperitoneal or cystoperitoneal shunting, and endoscopic fenestration. There is a debate about which method is the best. OBJECTIVE: The aim of this study is to evaluate the effectiveness and safety of endoscopic ventriculocystostomy (VC) and third ventriculostomy (ETV) for treatment of arachnoid cysts of the quadrigeminal cistern. METHODS: Twenty-eight patients with QACs who had undergone endoscopic treatment in our department between August 2007 and June 2014 were studied retrospectively. Patient age at the time of endoscopic treatment ranged from 5 months to 42 years, including 25 children (14 males and 11 females) and 3 adults (one male and two females). All patients presented with hydrocephalus and did not undergo shunting prior to neuroendoscopic surgery. The first endoscopic procedures included lateral ventricle cystostomy (LVC) together with ETV in 18 cases, third ventricle cystostomy (3rd VC) together with ETV in 3 cases, and double VC (3rd VC and LVC) together with ETV in 7 cases. Data were obtained on clinical and neuroradiological presentation, indications to treat, surgical technique, complications, and the results of clinical and neuroradiological follow-up. RESULTS: Complete success was achieved in 25 (89.3 %) of 28 cases. During the follow-up period, one case underwent endoscopic reoperation with success. Shunts were implanted in 2 patients due to progression of symptoms and increase in hydrocephalus after the first endoscopic operation. Shunt independency was achieved in 26 (92.9 %) of 28 cases. The cyst was reduced in size in 22 cases (78.6 %). Postoperative images showed a reduction in the size of the ventricles in 23 cases (82.1 %). There was no surgical mortality. Subdural collection developed in 4 cases (14.3 %) and required a transient subduroperitoneal shunt in 2 cases, whereas the other 2 patients were asymptomatic and did not require any surgical treatment. CONCLUSIONS: VC together with ETV through precoronal approach is an effective treatment for symptomatic QACs and should be the initial surgical procedure. The surgical indications should include signs of elevated ICP (including increased head circumference), Parinaud syndrome, gait ataxia, and nystagmus. Also, surgery is indicated by progressive enlargement of the cyst and young children with large cysts even if the patients are asymptomatic. Contraindications to surgery include the absence of symptoms (older children and adult) and isolated developmental delay. The main criterion for successful surgery should be improvement of clinical symptoms instead of reduced cyst volume and/or ventricular size. Repeated endoscopic procedures may be considered only for the patients whose symptoms improved after first endoscopic operation.

Impact of Disease Activity on Resting Energy Expenditure and Body Composition in Adult Crohn's Disease: A Prospective Longitudinal Assessment.

BACKGROUND: There is controversy about nutrition status and calorie needs during phases of active versus inactive adult Crohn's disease (CD). Results have been reported in cross-sectional studies, but longitudinal data are unavailable. Our aim was to explore whether disease activity had an impact on resting energy expenditure (REE) and body composition in adult patients with CD. MATERIALS AND METHODS: Adult patients were studied on 2 occasions with active and inactive CD. REE was measured by indirect calorimetry. Body composition was estimated from bioelectrical impedance analysis. Disease activity was measured using the Crohn's Disease Activity Index (CDAI). Regression analyses of REE with CDAI score, C-reactive protein, and erythrocyte sedimentation rate were also performed. RESULTS: Seventy-five patients were included. Patients with active CD had increased REE/body weight compared with patients with inactive disease (28.8 ± 5.4 vs 25.9 ± 4.3 kcal/kg, P < .001). Disease behavior and location, but not sex, had an impact on REE/body weight. Body mass index was lower in active disease than in remission (17.4 ± 3.0 vs 18.1 ± 2.6 kg/m(2), P = .010). Body composition was not affected by disease behavior or location. CONCLUSION: Patients with remission had a better nutrition status and decreased REE compared with those with active CD. REE could also be affected by disease location and behavior.

[A comparative study of induction of remission and cost-effectiveness of enteral nutrition versus infliximab in moderate-to-severe Crohn's disease].

OBJECTIVE: To compare the induction of remission and cost-effectiveness of enteral nutrition (EN) and infliximab (IFX) in moderate-to-severe active Crohn's disease(CD). METHODS: Moderate-to-severe active CD patients were divided into IFX group and EN group. Remission rate, time to remission and treatment cost were compared between the two groups. Clinical remission was defined as Crohn's disease activity index (CDAI) < 150. The quality of life was evaluated by inflammatory bowel disease questionnaire of quality of life (IBDQ). RESULTS: A total of 100 patients were analyzed, including 48 patients in IFX group and 52 patients in EN group. IFX group had higher remission rate [87.5% (42/48) vs 67.3% (35/52) , P = 0.017] and shorter time to remission [(11.00 ± 8.35) days vs (33.94 ± 14.60) days, P < 0.001] than EN group. Treatment costs before remission were similar in two groups (P = 0.351) . The increase of IBDQ scores before and after treatment in IFX group was much higher than that of EN group (42.74 ± 27.50 vs 7.57 ± 22.77, P < 0.001) . Similarly, patients in EN group had greater increase of body mass index (BMI) than that of IFX group [(1.32 ± 0.29)kg/m(2) vs (0.51 ± 0.07) kg/m(2), P < 0.001]. For patients with CDAI < 280, remission rate was not significantly different [85.7% (24/28) vs 81.8% (18/22) , P = 0.718] between the two groups, while treatment cost in EN group was less than that of IFX group [(16.1 ± 5.9)×10(3) RMB vs (22.9 ± 11.9)×10(3) RMB, P = 0.021]. CONCLUSIONS: For patients with severe CD (CDAI ≥ 280), IFX has higher remission rate, shorter time to remission and comparable treatment cost than EN. But for patients with CDAI < 280, EN group has comparable remission rate to IFX group with lower cost.

Magnetic resonance imaging appearance of the medial wall of the cavernous sinus for the assessment of cavernous sinus invasion by pituitary adenomas.

PURPOSE: The diagnostic criteria for cavernous sinus invasion (CSI) by pituitary adenomas are still unsatisfactory and controversial. For this reason, the study examined the appearance of the medial wall of the cavernous sinus (MWCS) on proton-density-weighted (PDW) magnetic resonance imaging (MRI) to determine its value for preoperative assessment of CSI. METHODS: A 3.0-Tesla MRI scanner was used to obtain preoperative PDW images and conventional MRI sequences of 48 consecutive pituitary adenomas, and the MWCS was examined in PDW images to determine the presence of CSI in comparison to surgical findings and three traditional MRI criteria: Knosp grading system (KGS); percentage of encasement of the internal carotid artery (PEICA); and replacement of cavernous sinus compartments (RCSC) by tumors. The value of the MWCS as seen on MRI was compared with that of the Ki-67 labelling index (Ki-67 LI). RESULTS: CSI images showed that continuity of the MWCS was interrupted and that tumor tissue had infiltrated the cavernous sinus (CS) compartments through the defects. In 96 CSs from 48 patients, the sensitivity of MRI visualization of the MWCS for detection of CSI was 93.3% with a specificity of 93.8%, which was significantly higher than with KGS, PEICA and RCSC (P=0.007, P=0.008 and P=0.056, respectively). Histopathological results showed no significant differences between MRI visualization of the MWCS and the Ki-67 LI. CONCLUSION: PDW imaging permits adequate visualization of the MWCS and is superior to traditional diagnostic criteria for the detection of CSI, providing accurate preoperative images for intraoperative navigation.

Gamma-ray rejection, or detection, with gadolinium as a converter.

Gadolinium is a competent neutron conversion material for neutron detection due to its extremely high neutron capture cross section. It differs from the other neutron reactive materials by emitting large amounts of low-energy electrons for the consequent signal generation in a detector. Such low-energy electrons, though abundant, are prone to be contaminated by internal and/or external gamma rays, such as the activated 43.0 keV K-X rays, given the high atomic number of gadolinium. While the 43.0 keV K-X ray ought to be rejected as it originates in part from the external gamma rays when neutron detection is concerned, the ability to separate this energy line from other signals points to a practical mode of gamma-ray detection by a thin-film semiconductor with gadolinium as a converter. In this paper, a gamma-ray discrimination scheme for neutron detection is studied, which also provides insight into gamma-ray detection with a small semiconductor device with gadolinium as a converter, in line with the same principle of isolating the K-X rays activated by high- or medium-energy gamma rays.

Comparing the community composition of European and eastern Chinese waterbirds and the influence of human factors on the China waterbird community.

We compared the European and eastern Chinese waterbird assemblages and checked whether the effects of human disturbance could be detected in the assemblages' composition. For the different Chinese provinces, we expected to find a negative effect of economic development on the mean bird species mass and on the proportion of bentivorous, piscivorous and insectivorous bird species. We also expected to find relatively fewer large species in the Chinese assemblage. Species rank-abundance curves were relatively similar, but China had significantly more species with smaller body masses. The China assemblage was characterized by relatively higher abundance of heavy-bodied species, contrary to our expectations. Mean bird body mass decreased in China with increasing disturbance and increasing gross domestic product (GDP). For coastal provinces in China the percentage of bentivorous, piscivorous and insectivorous bird species declined with increasing GDP, maybe through the increased use of pesticides or fertilizer.

[Effects of the improved FUS-invest investment for zirconium-oxide titanium crown and bridge on the reaction layer].

OBJECTIVE: To investigate the effects of the improved FUS-invest investment for zirconium-oxide titanium crown and bridge on the reaction layer. METHODS: 10 mm x 10 mm x 1 mm titanium castings were invested. Spectrum analysis was done to its reaction layer, the metallographic examination was observed and Vickers hardness was measured. RESULTS: The reaction layer was not obvious by the metallographic examination. The layer with plenty of Si was hardly detectable. The needle crystal layer diffused distribution on the surface of the titanium matrix. The depth was about 55 microm. Spectrum analysis showed that the contents of Si and Zr decreased as the depth increased. The microhardness, which obviously decreased from the surface to the matrix, tended to be equal with the hardness of the matrix after the depth reached 75 microm from the surface. CONCLUSION: The thickness of the reaction layer of the improved FUS-invest investment for zirconium-oxide titanium crown and bridge was decreased to 55 microm from 85 microm, which was the thickness before improvement.