Three-dimensional bone structure and bone mineral density evaluations of autogenous bone graft after sinus augmentation: a microcomputed tomography analysis

OBJECTIVE

The purpose of this study was to determine the relationships and differences in three-dimensional (3D) bone mineral density (BMD) and microtrabecular structures between autogenous bone grafts and their adjacent native bone after a healing period following maxillary sinus augmentation.

MATERIALS AND METHODS

Nine rod-shaped human bone biopsy samples were taken from patients receiving two-stage sinus augmentation therapy in implantation areas and analyzed using microcomputed tomography (micro-CT). Before micro-CT scanning, two BMD phantoms were placed near to the bone biopsy samples for executing BMD calculations of the grafted and native bone samples. In addition, 3D structural parameters of the trabeculae were analyzed for both the grafted and native bone, including percentage of bone volume [bone volume (BV)/tissue volume (TV)], bone-specific surface [bone surface (BS)/BV], trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), trabecular pattern factor (Tb.Pf), and structure model index (SMI).

RESULTS

No significant correlations with regard to BMD and trabecular-structure parameters were found between native bone and grafted bone; however, BS/BV and Tb.Pf were higher and Tb.Th and Tb.Sp were 37.35% and 12.74% lower in grafted bone than in native bone. For grafted bone, there were significant correlations (P < 0.05) between BMD and BV/TV, and Tb.N.

CONCLUSIONS

When using autogenous bone as a graft material, BMD and micromorphological conditions of grafted bone were not influenced by the condition of the native bone in the maxilla. Differences were found in surface complexity, trabecular thickness, trabecular separation, and the connectivity of trabeculae between grafted and native bone. The BMD in grafted bone was affected by the quantity of the trabeculae.

The effects of cortical bone thickness and trabecular bone strength on noninvasive measures of the implant primary stability using synthetic bone models

PURPOSE

This study investigated how the primary stability of a dental implant as measured by the insertion torque value (ITV), Periotest value (PTV), and implant stability quotient (ISQ) is affected by varying thicknesses of cortical bone and strengths of trabecular bone using synthetic bone models.

MATERIALS AND METHODS

Four synthetic cortical shells (with thicknesses of 0, 1, 2, and 3 mm) were attached to four cellular rigid polyurethane foams (with elastic moduli of 137, 47.5, 23, and 12.4 MPa) and one open-cell rigid polyurethane foam which mimic the osteoporotic bone (with an elastic modulus 6.5 MPa), to represent the jawbones with various cortical bone thicknesses and strengths of trabecular bone. A total of 60 bone specimens accompanied with implants was examined by a torque meter, Osstell resonance frequency analyzer, and Periotest electronic device. All data were statistically analyzed by two-way analysis of variance. In addition, second-order nonlinear regression was utilized to assess the correlations of the primary implant stability with the four cortex thicknesses and five strengths of trabecular bone.

RESULTS

ITV, ISQ, and PTV differed significantly (p < .05) and were strongly correlated with the thickness of cortical bone (R(2) > 0.9) and the elastic modulus of trabecular bone (R(2) = 0.74-0.99).

CONCLUSIONS

The initial stability at the time of implant placement is influenced by both the cortical bone thickness and the strength of trabecular bone; however, these factors are mostly nonlinearly correlated with ITV, PTV, and ISQ. Using ITV and PTV seems more suitable for identifying the primary implant stability in osteoporotic bone with a thin cortex.

Effects of orthodontic tooth movement on alveolar bone density

The object of this study was to evaluate the relationship between changes in the alveolar bone density around the teeth and the direction of tooth movement by using cone-beam computed tomography (CBCT). CBCT was used to measure the bone densities around six maxilla anterior teeth before and after 7 months of orthodontic treatment in eight patients. Each root was divided into three levels (cervical, intermediate, and apical) to determine whether the bone density change varied with the tooth level. Moreover, each level was divided into four regions (palatal, distal, mesial, and buccal sides). Three-dimensional computer models of the maxilla before and after orthodontic treatment were created to detect the direction of tooth movement. The percentage for all 144 samples [8 (patients) × 6 (teeth) × 3 (levels)] in which the side (palatal, distal, mesial, or buccal sides) of maximum bone density reduction (before and after orthodontic treatment) coincided with the direction of tooth movement was calculated; this was referred to as the "coincidence percentage". The bone density around the teeth reduced by 24.3 ± 9.5%. The average coincidence percentage for the eight patients was 59.0%. The coincidence percentages for the eight patients were 62.5%, 62.5%, and 52.1% at the cervical, intermediate, and apical levels, respectively. The obtained results demonstrate that the direction of tooth movement is associated with the side of maximum bone density reduction, and that CBCT is a useful approach for evaluating bone density changes around teeth induced by orthodontic treatment.

An inexact chance-constrained programming model for water quality management in Binhai New Area of Tianjin, China

In this study, an inexact-chance-constrained water quality management (ICC-WQM) model is developed for planning regional environmental management under uncertainty. This method is based on an integration of interval linear programming (ILP) and chance-constrained programming (CCP) techniques. ICC-WQM allows uncertainties presented as both probability distributions and interval values to be incorporated within a general optimization framework. Complexities in environmental management systems can be systematically reflected, thus applicability of the modeling process can be highly enhanced. The developed method is applied to planning chemical-industry development in Binhai New Area of Tianjin, China. Interval solutions associated with different risk levels of constraint violation have been obtained. They can be used for generating decision alternatives and thus help decision makers identify desired policies under various system-reliability constraints of water environmental capacity of pollutant. Tradeoffs between system benefits and constraint-violation risks can also be tackled. They are helpful for supporting (a) decision of wastewater discharge and government investment, (b) formulation of local policies regarding water consumption, economic development and industry structure, and (c) analysis of interactions among economic benefits, system reliability and pollutant discharges.

Single-camera panoramic stereo imaging system with a fisheye lens and a convex mirror

This paper presents a panoramic stereo imaging system which uses a single camera coaxially combined with a fisheye lens and a convex mirror. It provides the design methodology, trade analysis, and experimental results using commercially available components. The trade study shows the design equations and the various tradeoffs that must be made during design. The system's novelty is that it provides stereo vision over a full 360-degree horizontal field-of-view (FOV). Meanwhile, the entire vertical FOV is enlarged compared to the existing systems. The system is calibrated with a computational model that can accommodate the non-single viewpoint imaging cases to conduct 3D reconstruction in Euclidean space.

Systemic treatment with strontium ranelate promotes tibial fracture healing in ovariectomized rats

Systemic treatment with strontium ranelate (SR) was performed on ovariectomized (OVX) rats with fractured tibiae. Callus quality was assessed by radiographic, histological, micro-computerized tomography, and biomechanical examinations at 4 and 8 weeks after fracture. Results revealed that systemic applied SR promoted osteoporotic fracture healing.

INTRODUCTION

Several studies have demonstrated the dual effect of SR on osteoporotic and undisturbed bone. However, reports of their effect on osteoporotic fracture healing are limited. This study was designed to investigate the effects of SR on bone regeneration in OVX rats with fractured tibiae.

METHODS

Three months after being OVX, female Sprague-Dawley rats accepted bilateral osteotomy on proximal tibiae fixed with intramedullary wires and were divided into two groups: OVX and OVX + SR (625 mg/kg/day). Callus quality was evaluated at 4 and 8 weeks postfracture.

RESULTS

Compared with OVX group, SR treatment significantly increased bone formation, BMD, biomechanical strength, and improved microstructural properties of the callus. The ultimate load was increased by 211.0% and 61.4% (p<0.01), and the total bone volume of callus by 74.8% and 79.3% (p<0.01) at 4 and 8 weeks postfracture, respectively. SR treatment also promoted healing progress with increased osteogenesis at 4 weeks; more mature and tightly arranged woven or lamellar bone at 8 weeks across the fracture gap in histological analysis.

CONCLUSION

This study suggests that systemic treatment with strontium ranelate could promote tibial fracture healing in OVX rats.

[Diagnosis and treatment of arrhythmogenic right ventricular cardiomyopathy in children]

OBJECTIVE

To summarize the experience in diagnosis and treatment of arrhythmogenic right ventricular cardiomyopathy (ARVC) in children.

METHODS

A total of 14 children (7 females and 7 males) with ARVC were involved. The cases underwent electrocardiography, echocardiography, cardiac CT or MRI examinations. All cases were treated with sotalol or amiodarone in combination with propranolol. In 2 cases with drug-refractory ventricular extrasystoles, catheter ablation treatment was performed. In 6 cases with obvious impaired ventricular function, additional pharmacological therapy including vasodilators, diuretics, and digitalis were given.

RESULTS

Ventricular extrasystoles occurred in all 14 cases and ventricular tachycardia in 8 cases. Ten cases showed Epsilon wave on electrocardiography. All 14 cases had enlarged right ventricle and reduced right ventricular ejection fraction. CT or MRI examination showed right ventricular dilatation and a thinned wall of right ventricle in 10 cases. Ventricular extrasystoles or tachycardia disappeared in 7 cases and was reduced in 4 cases after treatment. The two children receiving catheter ablation treatment did not present ventricular extrasystoles or tachycardia in a 3-month follow-up. The heart function was improved in the 6 children with obvious impaired ventricular function after pharmacological therapy.

CONCLUSIONS

The clinical manifestations are diverse in children with ARVC. A definite diagnosis of ARVC should be based on a combination of electrocardiography and echocardiography examinations. Pharmacological therapy is effective partially. Catheter ablation treatment appears to be a promising option in patients with drug-refractory ventricular extrasystoles.

Vertical distribution of polybrominated diphenyl ethers (PBDEs) in soil cores taken from a typical electronic waste polluted area in South China

37 PBDE congeners were analyzed at six different depths in two soil cores taken from a typical electronic waste polluted area in South China. The PBDEs were congregated in the surface layer (0-5 cm) of soil cores and were 29 times in MK and 18 times in NW higher than the second lower layers (5-10 cm). As a whole, the concentrations of PBDEs were decreased with the soil depth increased in two cores. Lower brominated PBDE had higher penetrability than the deca-BDE in soil. The deca-BDE could be detected in deeper soil layers (15-20 cm in MK and 20-30 cm in NW) and the percentage of deca-BDE decreased with the increase of depth.

Tissue distribution of polybrominated diphenyl ethers (PBDEs) in captive domestic pigs, Sus scrofa, from a village near an electronic waste recycling site in South China

The dominant part of PBDEs residue in pig tissues was BDE-47 accounted for 48.2% approximately 66.9%, followed by BDE-99 from 15.9% to 24.2%. When the data were on lipid weight basis, the summation operatorPBDEs concentrations in tissues of individual pig showed the same order of liver > muscle, intestine > fat. Principal component analysis and PBDE congener mean concentration ratios of muscle versus liver (M/L), fat versus liver (F/L) and intestine versus liver (I/L) showed the higher accumulation ability of PBDEs in liver than in other tissues. And the PBDE mean concentration ratios of M/L, F/L and I/L had the trend of decrease with increasing bromination degree of PBDE congeners.

In utero smoke exposure, glutathione S-transferase P1 haplotypes, and respiratory illness-related absence among schoolchildren

BACKGROUND

The GSTP1 Ile105Val variant and secondhand tobacco smoke exposure have been independently associated with acute respiratory illness; however, susceptibility to in utero and secondhand tobacco smoke has yet to be examined in relation to variation across the GSTP1 locus.

OBJECTIVE

The purpose of this work was to determine whether variation across the GSTP1 locus is associated with respiratory illness-related school absences and to determine whether this relationship varies by in utero and secondhand tobacco smoke exposure.

METHODS

Tobacco smoke exposure status, incident respiratory-related school absence records, and DNA samples was ascertained for 1132 Hispanic and non-Hispanic white elementary school children as part of the Children's Health Study.

RESULTS

Four GSTP1 single-nucleotide polymorphisms were selected that accounted for 93% of the variation across the locus. Individual single-nucleotide polymorphism analyses showed a protective effect for the minor alleles in single-nucleotide polymorphisms 1 (rs6591255), 3 (GSTP1 Ile105Val: rs1695), and 4 (rs749174) for respiratory illness. The haplotype, which includes a minor allele for single-nucleotide polymorphisms 1, 3, and 4 (h1011), was associated with a decreased risk of respiratory illness. The protective effect of GSTP1 variants was lost among individuals exposed to in utero and secondhand tobacco smoke.

CONCLUSIONS

A common GSTP1 haplotype, which includes the functional Ile105Val polymorphism, was associated with respiratory-related school absences. The protection afforded by this haplotype was lost in children exposed to involuntary tobacco smoke. The paradigm of loss of genetic protection among those exposed to tobacco smoke has clinical and public health implications that warrant broader consideration in research and practice.

Measurement of milk D-3-hydroxybutyrate with a simple UV spectrophotometer method: an alternative assay method

The measurement of D-3-hydroxybutyrate (D-BHBA) in milk samples is an important tool for diagnosis of subclinical/clinical ketosis in dairy cows. We describe a simple UV spectrophotometric method for measuring the concentration of D-BHBA in milk of dairy cows. From two herds, 119 milk samples were taken from dairy cows. The standard-curve equation was y = 0.2582x + 0.0269 (R2 = 0.9967). The assay was highly specific with a minimum detection limit of 0.01 mmol/L and measuring range of up to 5 mmol/L. The recovery was between 99.35% and 100.22% and repeatability was 99.8%. The comparison between the spectrophotometric method and the fluorometric method revealed a close correlation (r = 0.9939). These results show that the spectrophotometric method can be successfully used as an alternative method to measure D-BHBA content in milk.

Electrical transport properties of fullerene peapods interacting with light

In this paper, we investigate the transport properties of field-effect transistors (FETs) based on various kinds of fullerene (C(60), C(70), and C(84)) peapods. The encapsulation of various fullerenes inside single-walled carbon nanotubes (SWNTs) is characterized by TEM and Raman spectroscopy. Our results indicate that the transport characteristics of p-type SWNTs are extremely sensitive to the encapsulation of various kinds of fullerene. In the absence of light illumination, the threshold voltage of p-type SWNTs shifts towards positive values after C(60) and C(70) encapsulation, and ambipolar transport characteristics are observed for C(84) peapods. The photoinduced electron transfer phenomenon is observed for fullerene peapods under light illumination. The optical response for C(60) and C(70) peapod FET devices is reflected in a shift of threshold voltage towards negative values, and a recoverable characteristic is observed when light is off. After a long period of light illumination, in contrast to p-type C(60) and C(70) peapods, an n-type transport characteristic is observed on C(84) peapods.

Aromatase inhibitors in ovarian cancer: is there a role?

Estrogen plays a role in ovarian tumorigenesis. Aromatase is the enzyme required for the synthesis of estrogen via conversion of androgen to estrogen, which is the major source of estrogen in postmenopausal women. Aromatase is present in normal ovaries and other tissues (e.g., fat and muscle) as well as in 33-81% tumor tissues of ovarian cancer. Aromatase inhibitors (AIs) block estrogen synthesis by inhibiting aromatase activity. In patients with recurrent ovarian cancer, single-agent AI therapy has been shown to elicit clinical response rates of up to 35.7% and stable disease rates of 20-42%. Given the limited treatment options for recurrent ovarian cancer and the favorable safety profile and convenient use, AI is a rational option for prolonging platinum-free interval in recurrent ovarian cancer. Further studies are required to determine the efficacy of combination treatment with AIs and biological agents, determine the benefit of AIs for treating special types of ovarian cancer (e.g., endometrioid type), and identify biomarkers for targeted patient selection. This review summarizes the current epidemiologic, preclinical, and clinical data regarding estrogen's role in ovarian cancer, the expression and regulation of aromatase in this disease, the development and characteristics of the three generations of AIs, and the preclinical and clinical studies of AIs in the treatment of ovarian cancer.

Glutathione S-transferase P1, maternal smoking, and asthma in children: a haplotype-based analysis

BACKGROUND

Glutathione S-transferase P1 (GSTP1) plays a role in a spectrum of respiratory diseases; however, the effects of sequence variation across the entire locus in asthma pathogenesis have yet to be determined.

OBJECTIVES

This study was designed to investigate whether sequence variations in the GSTP1 coding and promoter regions are associated with asthma and wheezing outcomes and to determine whether variants affect susceptibility to maternal smoking.

METHODS

Four haplotype tagging SNPs were selected that accounted for 83% of the common haplotypic variation in GSTP1. The associations of GSTP1 variants with asthma and wheezing were assessed among white children in the Children's Health Study (CHS).

RESULTS

The Ile105Val allele and a SNP in the upstream promoter region (SNP1: rs6591255, putative transcription factor 1 binding site) were associated with asthma and wheezing outcomes, an association observed in two cohorts of the CHS recruited in different years. Haplotypes that included both the promoter SNP (i.e., rs6591255) and the 105 Val variant were associated with an increased risk for asthma in non-Hispanic whites. Using SNP- and haplotype-based approaches, the effect of maternal smoking on wheezing was largest in children with the Ile105Val allele.

CONCLUSIONS

Variants in both the promoter and coding regions of the GSTP1 locus may contribute to the occurrence of childhood asthma and wheezing and may increase susceptibility to adverse effects of tobacco-smoke exposure.

Vision processing for realtime 3-D data acquisition based on coded structured light

Structured light vision systems have been successfully used for accurate measurement of 3-D surfaces in computer vision. However, their applications are mainly limited to scanning stationary objects so far since tens of images have to be captured for recovering one 3-D scene. This paper presents an idea for real-time acquisition of 3-D surface data by a specially coded vision system. To achieve 3-D measurement for a dynamic scene, the data acquisition must be performed with only a single image. A principle of uniquely color-encoded pattern projection is proposed to design a color matrix for improving the reconstruction efficiency. The matrix is produced by a special code sequence and a number of state transitions. A color projector is controlled by a computer to generate the desired color patterns in the scene. The unique indexing of the light codes is crucial here for color projection since it is essential that each light grid be uniquely identified by incorporating local neighborhoods so that 3-D reconstruction can be performed with only local analysis of a single image. A scheme is presented to describe such a vision processing method for fast 3-D data acquisition. Practical experimental performance is provided to analyze the efficiency of the proposed methods.

Detection of human parvovirus B19 in papillary thyroid carcinoma

To evaluate whether parvovirus B19, a common human pathogen, was also involved in papillary thyroid carcinoma (PTC), 112 paraffin-embedded thyroid specimens of benign nodules, papillary, medullary and follicular carcinomas, and normal controls were examined for B19 DNA and capsid protein by nested PCR, in situ hybridisation (ISH) and immunohistochemistry (IHC). The expression of the nuclear factor-κB (NF-κB) was investigated by IHC. The results showed B19 DNA commonly exists in human thyroid tissues; however, there were significant differences between PTC group and normal controls, and between PTC and nonneoplastic adjacent tissues (P<0.001). The presence of viral DNA in PTC neoplastic epithelium was confirmed by laser-capture microdissection and sequencing of nested PCR products. B19 capsid protein in PTC group was significantly higher than that of all the control groups and nonneoplastic adjacent tissues (P⩽0.001). Compared with control groups, the activation of NF-κB in PTC group was significantly increased (P⩽0.02), except for medullary carcinomas, and the activation of NF-κB was correlated with the viral protein presence (P=0.002). Moreover, NF-κB was colocalised with B19 DNA in the neoplastic epithelium of PTC by double staining of IHC and ISH. These results indicate for the first time a possible role of B19 in pathogenesis of PTC.

Support vector networks in adaptive friction compensation

This paper presents our research on how support vector regression (SVR) and parametric adaptive learning, which are normally used independently, can be exploited together to benefit adaptive neural control. In the context of friction compensation for servo-motion control systems, we present the notion of support vector networks which play an essential role in combining SVR and adaptive neural network (NN) in cooperation for friction estimation. The analysis shows that the proposed support vector network contributes not only to the performance improvement but also to the practical usefulness in adaptive friction compensation. Experimental results are reported to demonstrate the effectiveness of the proposed approach.

Systemic anticancer therapy in gynecological cancer patients with renal dysfunction

Chronic kidney disease is a common occurrence in patients with gynecological cancer. Systemic anticancer treatment in such patients is a challenge for clinicians because of altered drug pharmacokinetics. For those drugs that are excreted mainly by the kidneys, decreased renal function may lead to increased systemic exposure and increased toxicity. Dose adjustment based on pharmacokinetic changes is required in this situation to avoid life-threatening toxicity. In this review, we summarize the nephrotoxicity and pharmacokinetic data of agents commonly used in systemic anticancer treatment of gynecological cancers and dose adjustment guidelines in the presence of impaired renal function. We review 17 medications that need dose adjustment (cisplatin, carboplatin, doxorubicin, epirubicin, cyclophosphamide, ifosfamide, topotecan, irinotecan, etoposide, capecitabine, bleomycin, methotrexate, actinomycin D, granulocyte-macrophage colony-stimulating factor, metoclopramide, cimetidine, and diphenhydramine) as well as 27 drugs that do not (paclitaxel, docetaxel, pegylated liposomal doxorubicin, gemcitabine, oxaliplatin, fluorouracil, vincristine, letrozole, anastrozole, tamoxifen, leuprorelin, megestrol, gefitinib, erlotinib, trastuzumab, leucovorin, granulocyte colony-stimulating factor, erythropoietin, ondansetron, granisetron, palonosetron, tropisetron, dolasetron, aprepitant, dexamethasone, lorazepam, and diazepam). We also review the formulae commonly used to estimate creatinine clearance, including Cockcroft-Gault, Chatelut, Jelliffe, Wright, and the Modification of Diet in Renal Disease study formulae.

Production and characterization of monoclonal antibodies to (poly100)S1 protein of avian infectious bronchitis virus

Fragments within S1 genes ((poly100)S1) of infectious bronchitis virus (IBV) strains ZJ971, M41 and SC021202 (SC) were subcloned into a prokaryotic expression vector and expressed in Escherichia coli. Monoclonal antibodies (mAbs) against the recombinant (poly100)S1 proteins were produced, characterized and used to analyse epitopes on the S1 subunit of IBV. Nine mAbs raising from the three (poly100)S1 proteins recognized five different epitopes of the S1 subunit, designated as S1-A, B, C, D and E. Epitopes S1-C and S1-D are common for the three IBV strains, while S1-A and S1-B exist on ZJ971 and M41 strains, and S1-E was a strain-specific epitope for SC strain. Immunocytochemistry indicated that all the mAbs to the (poly100)S1 proteins can react with the homologous S1 glycoprotein expressed in Vero cells. Moreover neutralization test demonstrated that only mAbs 6E2, 4F9 and 6G4 had neutralization activity for the homologous IBV. These mAbs to (poly100)S1 protein were potential candidates for detecting and distinguishing IBV strains, and also used to examine antigenic variation of the S1 protein.

Toward dynamic recalibration and three-dimensional reconstruction in a structured light system

We present a method for dynamic recalibration and 3D reconstruction via a structured light system. Assuming that the light planes cast from the digital light projector have been calibrated off-line, we show that the focal length, aspect ratio, and all motion parameters of the camera can be determined on-line. Then the 3D reconstruction can be carried out by either a traditional triangulation method or a more efficient transformation-based method. In the latter method, a single image is sufficient for the whole process of calibration and reconstruction. Thus a hand-held camera can be used. Computer simulation and real data experiments were carried out to validate the method.