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The aim of this study was to investigate the changes in type II neuregulin-1 (NRG-1) during the regeneration process following autologous sciatic nerve transplantation in rats.A total of 40 Sprague-Dawley(SD) rats were randomly divided into an experimental and control group. There were 20 rats in each group.Five time points were set on the 3rd, 7th, 14th, 21st and 28th days after surgery. In the experimental group, reversed autologous transplantation of the sciatic nerve was performed, while in the control group, the sciatic nerve was only exposed. Changes in the rat footprints were observed at different time points, the sciatic functional index(SFI) was calculated, regeneration of the myelin sheath were observed by transmission electron microscopy, type II NRG-1 protein were detected by western blotting, and type II NRG-1 mRNA were detected by real-time PCR.The SFI of the experimental group was lower than that of the control group at all time points after surgery, and the SFI of the experimental group was gradually increased. The expression of type II NRG-1 protein in the experimental group was significantly increased on the 3rd day, peaking on the 7th day, and continued until the 28th day after surgery. The area of medullated nerve fibers(um2) in the experimental group was significantly different from that in the control group on the 7th, 14th, 21st and 28th days(P 0.01).Type II NRG-1 peaked between the 3rd day and 14th day after autologous nerve transplantation and was probably involved in the regulation of myelin sheath regeneration during this period.

Objective: To observe the significance of subchondral bone microfracture in the human osteoarthritic tibial plateau on cartilage tidemark drift.Methods: Human knee tibial plateau cartilage samples with different OARSI grades were obtained, and the numbers of cartilage tidemarks and microfracture lines were determinedafter safranin O staining and compared among groups. Osteogenesis caused by microfracture in subchondral bone was observed and staged according to biological properties.Immunohistochemistry, western blotting, PCR and laser microdissection were performedto detect the biological properties of osteogenic areas caused by microfractures.The accompanying relationship between the ossification process and new tidemark formation inosteogenic areas caused by microfractures was then evaluated.Results: With the increase in OARSI grade, the numbers of cartilage tidemarks and subchondral bone microfracture lines in human knee tibial plateau cartilage tissue samples showed increasing trends.The subchondral bone microfracture line was observed toextend as far asthe basal area of hyaline cartilage and cause endochondral osteogenesis.The endochondral osteogenesis caused by subchondral microfracture was categorized into chondrocyte,calcareous sedimentary and ossification stages. A new tidemark appeared in the osteogenic region near the hyaline cartilage when the ossification process of the osteogenic region was completed.Conclusions:Endochondral osteogenesis canoccur at the base of hyaline cartilage induced by microfractures in the tibial plateau subchondral bone. A new cartilage tidemark can form on the side of the osteogenic tissue close to hyaline cartilage when the process of osteogenesis is completed.There is a positive correlation between the degree of cartilage tissue degeneration and the number of tidemarks in articular cartilage.

Objective: CA-125 is widely used as biomarker of ovarian cancer. However, CA-125 suffers low accuracy. We developed a hybrid analytical model, the Ovarian Cancer Decision Tree (OCDT), employing a two-layer decision tree, which considers genetic alteration information from cell-free DNA along with CA-125 value to distinguish malignant tumors from benign tumors. Methods: We consider major copy number alterations at whole chromosome and chromosome-arm level as the main feature of our detection model. Fifty-eight patients diagnosed with malignant tumors, 66 with borderline tumors, and 10 with benign tumors were enrolled. Results: Genetic analysis revealed significant arm-level imbalances in most malignant tumors, especially in high-grade serous cancers in which 12 chromosome arms with significant aneuploidy ( PConclusions: The results suggested that genetic variations extracted from cfDNA can be combined with CA-125, and together improved the differential diagnosis of malignant from benign ovarian tumors. The model would aid in the pre-operative assessment of women with adnexal masses. Future clinical trials need to be conducted to further evaluate the value of CScore in clinical settings and search for the optimal threshold for malignancy detection.

Objective This study aims to develop an artificial intelligence-based method to screen patients with left ventricular ejection fraction (LVEF) of 50% or lesser using electrocardiogram (ECG) data alone. Methods Convolutional neural network (CNN) is a class of deep neural networks, which has been widely used in medical image recognition. We collected standard 12-lead ECG and transthoracic echocardiogram (TTE) data including the LVEF value. Then, we paired the ECG and TTE data from the same individual. For multiple ECG-TTE pairs from a single individual, only the earliest data pair was included. All the ECG-TTE pairs were randomly divided into the training, validation, or testing data set in a ratio of 9:1:1 to create or evaluate the CNN model. Finally, we assessed the screening performance by overall accuracy, sensitivity, specificity, positive predictive value, and negative predictive value. Results We retrospectively enrolled a total of 26 786 ECG-TTE pairs and randomly divided them into training (n = 21 732), validation (n = 2 530), and testing data set (n = 2 530). In the testing set, the CNN algorithm showed an overall accuracy of 73.9%, sensitivity of 69.2%, specificity of 70.5%, positive predictive value of 70.1%, and negative predictive value of 69.9%. Conclusion Our results demonstrate that a well-trained CNN algorithm may be used as a low-cost and noninvasive method to identify patients with left ventricular dysfunction.

Objective. Adding vitamin E to highly cross-linked polyethylene liners is frequently performed in clinical practice, aiming at reducing liner wear, increasing liner survival, and delaying revision surgery. This study is aimed at evaluating the revision rate, total femoral head penetration, and postoperative clinical function of highly cross-linked polyethylene liners with and without vitamin E in total hip arthroplasty. Methods. We conducted a systematic literature search to identify the use of highly cross-linked vitamin E liners compared to other liners in patients who received total hip arthroplasty (THA) before April 2021. The study quality assessment and data collection were conducted by two independent reviewers. Studies were artificially grouped, and vitamin E-enhanced liners (VE-PE) were compared with vitamin E-free liners (non-VE-PE). Analyses were executed using Review Manager version 5.4.1. Results. From the preliminary screening of 568 studies, fourteen studies met the research criteria. Compared to non-VE-PE, using VE-PE reduced the all-cause revision rate ( odds ratio = 0.54 ; 95% confidence interval (CI) 0.40, 0.73; P < 0.0001 ). The total femoral head penetration of the VE-PE was lower than that of the non-VE-PE ( mean difference = − 0.10 ; 95% CI -0.17, -0.03; P = 0.007 ). However, there was no difference in clinical function, including the Harris Hip Score and EuroQol Five-Dimension Questionnaire scores. Conclusion. Compared to the liners without vitamin E, the addition of vitamin E to liners could reduce the all-cause revision rate by approximately 46% in the short-term follow-up. In addition, even though addition of vitamin E could also slow down femoral head penetration, there is no contribution to clinical function.

Background This study aimed to investigate the trend of cardiovascular disease (CVD)-specific mortality in patients with non-small cell lung cancer (NSCLC) and identify prognostic factors for CVD-specific death in stage NSCLC patients. Methods In this study, 270,618 NSCLC patients were collected from the Surveillance, Epidemiology, and End Results database. CVD- and NSCLC-specific cumulative mortality and proportion of death were calculated and graphically displayed to describe the probability of specific endpoints. Prognostic factors for CVD-specific mortality were evaluated by cause-specific hazard ratios (HR) with 95% confidence intervals (CI) using the competing risk model with non-cardiovascular death as competing risks. Results Among all competing causes of death, lung cancer resulted in the highest cumulative mortality, followed by CVDs and other causes. In the proportion of cause-specific death, heart diseases accounted for approximately 5.3% of the total death, only secondary to primary cancer. In all three stages, higher age, squamous cell carcinoma, and no-or-unknown chemotherapy and/or radiotherapy were associated with a higher risk of CVD-specific death, while surgery treatment seemed to be a protective factor. Female gender was statistically related to CVD-specific death in stage I and III patients with HRs of 0.84 (0.78–0.91) and 0.84 (0.77–0.93), respectively. Interestingly, right-sided laterality was correlated with lower CVD-specific mortality with HR of 0.82 (0.74–0.90) in stage III. Conclusions This study illustrated the historical trend of CVD-specific death in NSCLC patients and assesses potential prognostic risk factors, highlighting the involvement of cardio-oncology teams in cancer treatment to provide optimal comprehensive care and long-term surveillance for cancer patients.

Quercetin has attracted more attention in recent years due to its protective role against ischemia/reperfusion injury. Quercetin can alleviate oxidative stress injury through the inhibition of NADPH oxidase and xanthine oxidase, blockage of the Fenton reaction, and scavenging of reactive oxygen species. Quercetin can also exert anti-inflammatory and anti-apoptotic effects by reducing the response to inflammatory factors and inhibiting cell apoptosis. Moreover, it can induce vasodilation effects through the inhibition of endothelin-1 receptors, the enhancement of NO stimulation and the activation of the large-conductance calcium-activated potassium channels. Finally, Quercetin can also antagonize the calcium overload. These multifaceted activities of Quercetin make it a potential therapeutic alternative for the treatment of ischemia/reperfusion injury.

Accumulating evidence indicates the occurrence and development of diabetic complications relates to not only constant high plasma glucose, but also glucose fluctuations which affect various kinds of molecular mechanisms in various target cells and tissues. In this review, we detail reactive oxygen species and their potentially damaging effects upon glucose fluctuations and resultant downstream regulation of protein signaling pathways, including protein kinase C, protein kinase B, nuclear factor-κB, and the mitogen-activated protein kinase signaling pathway. A deeper understanding of glucose-fluctuation-related molecular mechanisms in the development of diabetic complications may enable more potential target therapies in future.

Objectives Total hip arthroplasty is a reliable therapeutic intervention in patients with ankylosing spondylitis, in whom the aims of surgery are to reduce pain, restore hip function and improve quality of life. The current study is a retrospective analysis of the clinical and radiographic findings in a consecutive series of patients with hip ankylosis associated with severe ankylosing spondylitis who underwent bilateral primary total hip arthroplasty using non-cemented components. Methods From June 2008 to May 2012, total hip arthroplasty was performed on 34 hips in 17 patients with bilateral ankylosis caused by ankylosing spondylitis. The study patients included 13 men and 4 women with a mean age of 24.2 years. The mean duration of disease was 8.3 years and the average duration of hip involvement was 7.6 years. All patients had severe hip pain and dysfunction with bilateral bony ankylosis and no range of motion preoperatively and all underwent bilateral cementless total hip arthroplasty performed by a single surgeon. Joint pain, range of motion (ROM), and Harris hip scores were assessed to evaluate the postoperative results. Results At a mean follow-up of 31.7 months, all patients had experienced significant clinical improvement in function, ROM, posture and ambulation. At the final follow-up, the mean postoperative flexion ROM was 134.4° compared with 0° preoperatively. Similar improvements were seen in hip abduction, adduction, internal rotation and external rotation. Postoperatively, 23 hips were completely pain-free, six had only occasional discomfort, three mild to moderate pain and two severe pain. The average Harris Hip Score improved from 23.7 preoperatively to 65.8 postoperatively. No stems had loosened at the final follow-up in any patient, nor had any revision surgery been required. Conclusions Bilateral severe hip ankylosis in patients with ankylosing spondylitis can be treated with cementless bilateral synchronous total hip arthroplasty, which can greatly improve hip joint function and relieve pain without significant complications. Provided the overall physical condition of a patient and their economic situation make surgery a feasible option and the surgeon is experienced, this treatment is a worthwhile surgical intervention for bilateral hip bony ankylosis. However, the technically demanding nature of the procedure and potential pre- and post-operative problems should not be underestimated.

Background: Alendronate has been used to prevent or treat glucocorticoid-induced osteoporosis (GIO), data regarding its efficacy are inconsistent. We conducted the current systematic review and meta-analysis to evaluate both efficacy and safety of alendronate in the treatment of GIO. Methods: PubMed, Embase, the Cochrane Controlled Trials Registry, and the China Academic Journal Network Publishing Databases were searched up through March 1, 2018. Randomized controlled trials (RCTs) involving patients which received alendronate treatment were included. Outcome measures were bone mineral density (BMD) changes, bone fractures, and adverse reactions. Data from the individual studies were pooled using random or fixed effect models based on heterogeneity. Effect size was reported as standardized mean differences (SMD) for continuous outcomes and pooled odds ratios (OR) for dichotomous outcomes, with 95% confidence interval (CI). Results: Overall, 10 studies involving 1002 patients were included in the present investigation. Alendronate treatment significantly increased BMD of the lumbar spine and femoral neck during 6 to 24 months. These beneficial effects were apparent at 12 months after treatment for the lumbar spine but not the femoral neck BMD. Alendronate treatment did not significantly change fracture risk nor induce significant differences in adverse gastrointestinal effects. Conclusion: Alendronate significantly increases BMD of the lumbar spine and femoral neck in patients with GIO, but does not appear to reduce the risk of fractures. As relatively insufficient data regarding the GIO fracture incidence has been reported, more RCTs need to be carried out to determine the efficacy of alendronate in the prevention of GIO fracture.

As the crucial junction in transportation lines, more attention should pay to the safety of bridges. However, the collapse of bridges under earthquake threats the safe of lifeline engineering seriously. Unseating prevention devices are the effective structural measure to prevent collapse under unexpected earthquake. The design of unseating prevention devices need not only to meet the deformation demand of bridge during normal operations, but also to limit the oversize displacement under unexpected earthquake. Combined with relational design standards at home and abroad, unseating prevention devices have been designed for bridge to prevent collapse. The research results show that the unseating prevention devices with reasonable parameter will decrease the relative displacement between superstructure and substructure, improve the seismic performance and integrality of bridge, and make the seismic load to be well-distributed among the piers.

The present study aimed to determine the mechanism by which low‑intensity intermittent negative pressure affects the differentiation and proliferation of human mesenchymal stem cells (MSCs). Alkaline phosphatase (ALP) activity, type I collagen and vascular endothelial growth factor (VEGF) were detected to analyze differentiation. MTT and flow cytometry were employed to measure proliferation and apoptosis. Western blot analysis was used to examine endoplasmic reticulum (ER) stress‑associated factors. This study was divided into two groups, including a normal group (without any treatment) and vacuum group (treated with a vacuum). There was a significant decrease in the proliferation of cells in the vacuum group. The number of cells in S phase was reduced significantly, while the rate of apoptosis and the activity of ALP were markedly increased under vacuum conditions. Expression of collagen type I and VEGF was significantly increased, and the ratio of osteoprotegrin to osteoprotegrin ligand was decreased significantly in the vacuum group. ER stress‑associated proteins, p‑PRKR‑like ER kinase, inositol‑requiring enzyme 1 and cleaved activating transcription factor 6, as well as the downstream factors, were activated when treated with negative pressure. In conclusion, treatment with low‑intensity and intermittent negative pressure may inhibit the proliferation of MSCs and trigger ER stress‑associated cellular apoptosis, further enhancing osteogenesis activity and inducing differentiation to osteoblasts.

The collapse-proof effect of unseating prevention devices are influenced by the design parameters under earthquake. Combine with existing relational design standards of unseating prevention devices at home and abroad, the dynamical analysis has been used to get the seismic response of bridges with different parameter cable-unseating prevention devices. The influence of design parameters on the collapse-proof effect and internal force of unseating prevention devices are been analyzed. The result show that the unseating prevention devices can play the role to proof the collapse, and it can enhance the anti-pushing rigidity and integrity of structure. The effect of collapse-proof decrease as the cable length and primary clearance increase, the internal force of unseating prevention devices is larger than the design bearing capacity while the parameters are both smaller, even some has exceed its yield tension.

The constitutive relation of concrete under uniaxial tension and compression is an essential theoretical basis for structural analysis of concrete. Because of the lack of sufficient stiffness for ordinary test device, a stable decline branch of stress-strain curve could not be obtained. The condition of realizing the stress-strain complete curve for concrete uniaxial tension and compression is derived. The experiment device for uniaxial tension and compression was designed and fabricated with increasing stiffness method. Experiments were carried out for concrete with grade C30~C60 and strain rate 10-5/s~10-2/s. The equation for stress-strain curve in the rising branch were obtained and so were the complete stress-strain curve of uniaxial tension and compression under different strain ratio, which provide the theoretical basis for concrete structural analysis.

Dynamic and static load testing for Dutou major Bridge was conducted. the test projects, the layout of measuring points and observation methods, test loadings, test methods, test results were presented, the test results showed that the strength and stiffness behavior of the bridge could meet the requirements of designation, the structure lied in a flexible working stage under test load.

The constitutive relation of concrete under uniaxial compression is the essential theoretical basis for structural analysis of concrete. Because of lack of sufficient stiffness for ordinarily tester, stable falling branch of stress-strain curve cannot be obtained. The common methods to increase rigidity of loading system include direct and indirect method. The condition of realizing the stress-strain complete curve for concrete uniaxial compression is derived. A set of stiffness experimental equipment is designed by using the indirect method, which has the advantages of simple, dependable and strong adaptability. Experiment shows that stress-strain complete curve of uniaxial compression under different strain rate could be achieved by using this equipment and electro-hydraulic loading system of MTS co. ltd. It will lay foundation for putting forward the stress-strain curve equation of uniaxial tension and compression under considering the effect of strain rate. It can provide theoretical basis for structural analysis of concrete.

The capability of structure resisting progressive collapse depends on controlling the dispersion of damage by uncommon agency in the part of the structure and to avoid the destruction just likes the Domino action. For the RC frame, when one column under the beams was broken, the key to avoid progressive collapse is whether the frame beams can bear the column’s load to produce a new way for transmitting the force or not. In this paper, the simulation analysis to a six-layer frame structure which designed by the concrete structural design codes is put up according to the four failure position of columns. The following conclusions are concluded: the damage in vertical region does not appear or appear very little because of a strong stiffness in joint between invalid column and beam. Structural collapse was resulted by the collapse stress from displacement transfering the other end of beam connected with columns.

Specific accumulation of radiolabeled antisense oligonucleotides as a result of binding by an antisense mechanism to target mRNAs in tumor has been repeatedly observed. However, the mechanisms responsible for nonspecific cellular accumulation remain almost completely unexplored. We have occasionally observed in cell culture nonspecific accumulations of 99m Tc-labeled sense, scrambled or random control oligonucleotides in tumor cells comparable to or even higher than those of the corresponding antisense oligonucleotides. We have also observed that these nonspecific accumulations of control oligonucleotides are sequence dependent. To explore the influence of base composition on nonspecific accumulation, we used MCF-7 breast cancer cells, along with 10 uniform phosphorothioates and 5 uniform phosphodiesters oligonuc leotides. Three of the phosphorothioates were antisense against different sites within the survivin mRNA, and two were the corresponding sense and scrambled controls. In addition, the accumulations in MCF-7 cells of radiolabeled poly A, poly C, poly T and poly GGGA phosphorothioate oligonucleotides were also studied to explore the influence of each nitrogenous base on the nonspecific cell accumulations of phosphorothioate oligonucleotides. Our results show that guanine content is an important determinant of nonspecific cellular accumulations under the conditions of this investigation. If this observation can be shown to be universally applicable to other cell types, then the selection of control sequences in studies of antisense tumor targeting should avoid those that are guanine rich, if possible.

The attempt to target the limited copies of messenger RNA (mRNA) in vivo with radiolabeled nucleobase oligomers as antisense probes is challenging. Selecting an antisense molecule with superior properties, enhancing the cellular kinetics, and improving the radiolabeling chemistry would be the reasonable approach to accomplish this goal. The present study reports a method to construct a chimera of phosphorodiamidate morpholino nucleobase oligomer (MORF) covalently conjugated to a peptide containing a cell membrane transduction Tat peptide and an N 2 S 2 chelator for technetium-99m ( 99m Tc) radiolabeling (N 2 S 2 -Tat-MORF). The radiolabeling properties and cellular kinetics of 99m Tc-N 2 S 2 -Tat-MORF were measured. As hypothesized, the preparation of 99m Tc-N 2 S 2 -Tat-MORF could be achieved by an instant one-step method with labeling efficiency greater than 95%, and the 99m Tc-N 2 S 2 -Tat-MORF showed distinct properties in cell culture from those of a control, the same MORF sequence without Tat but with mercaptoacetyltriglycine (MAG 3 ) as chelator for 99m Tc ( 99m Tc-MAG 3 -MORF). 99m Tc-N 2 S 2 -Tat-MORF achieved maximum accumulation of about 35% within 2 h, while 99m Tc-MAG 3 -MORF showed lower and steadily increasing accumulations but of less than 1% in 24 h. These preliminary results demonstrated that the proposed chimera has properties for easy labeling, and 99m Tc-N 2 S 2 -Tat-MORF prepared by this method possesses enhanced cellular kinetics and merits further investigation for in vivo mRNA targeting.

Technetium-99m labeled ubiquicidin peptide 29-41 ((99m)Tc-UBI) is a cationic human antimicrobial peptide fragment that has been shown to bind bacteria in vitro and accumulates at sites of infection in experimental animals. To help determine if (99m)Tc-UBI is bound to the bacterial cell envelope by a simple nonspecific electrostatic interaction, a comparative study of the in vitro binding of (99m)Tc-UBI and two different (99m)Tc labeled cationic peptides ((99m)Tc-Tat-1-Scr and (99m)Tc-Tat-2-Scr) to bacteria and to two tumor cell line (LS174T and ACHN) was performed. The in vivo specificity of (99m)Tc-UBI for infection in mice was also evaluated using dual labels in the same animal and comparing the target/non-target ratio for (67)Ga-citrate and (99m)Tc-UBI at sites of induced infection and sterile inflammation. Under conditions of this study, the in vitro binding of (99m)Tc-UBI, (99m)Tc-Tat-1-Scr and (99m)Tc-Tat-2-Scr to S. aureus was 35, 78 and 87% respectively. While the binding of (99m)Tc-Tat-1-Scr and (99m)Tc-Tat-2-Scr was 37 and 33% to colon tumor cells (LS174T) and 39 and 41% to renal tumor cells (ACHN) respectively, the binding of (99m)Tc-UBI to both cell types was much lower at less than 4%. In vivo studies revealed that there is a significant difference (p < 0.05) in the radioactive accumulation of (99m)Tc-UBI between the sites of infection and inflammation compared to (67)Ga-citrate. Thus, (99m)Tc-UBI showed an average infection/inflammation ratio of 2.08 +/- 0.49 compared to 1.14 +/- 0.45 for (67)Ga-citrate. In conclusion, the in vitro and in vivo results provide evidence that a specific mechanism is responsible of the (99m)Tc-UBI bacterial intracellular accumulation.

An important limitation restricting antisense nuclear medicine imaging is low radioactivity accumulations in target cells. The Tat peptide (Tat), a basic domain of the HIV Tat protein, has been shown to enhance cell accumulation of various biomolecules. PURPOSE: The influence of Tat, as a cationic carrier, on the accumulation in cell culture of anionic antisense DNAs bound electrostatically rather than covalently was investigated. To establish specificity of the accumulation, antisense DNA and control sequence were studied along with four different peptides. The technique of in situ reverse transcription was used to assay the in vivo hybridization of antisense DNA to the target mRNA in cultured live cells when transducted with the Tat peptide. METHODS: Uniform phosphorothioated DNAs were radiolabeled with 99mTc via Hynic/tricine. This 18 mer antisense DNA against RIα mRNA along with its sense and random control was studied in ACHN cells with the four peptides as carriers. RESULTS: The addition of Tat significantly increased cell accumulations. At 12 hours accumulations went from 14% to 45% for the antisense DNA and from 4% to 12% for control. Furthermore, an antisense effect was again suggested, now with the Tat carrier, by the significantly higher accumulation of 99mTc on both antisense DNAs vs. controls. Moreover, the accumulated antisense DNA enhanced with the Tat carrier was capable of priming reverse transcription as determined by an in situ assay suggesting that the DNA could escape from entrapment in endosome or lysosome vesicles for hybridization. However, differences in cellular accumulation with either Tat compared to either scrambled peptide were not significant, showing that the Tat in this study was functioning merely as a cationic carrier. CONCLUSIONS: Although electrostatic binding of antisense DNA to Tat is convenient, the association may mask the unique transduction properties of the peptide. Nevertheless, a promising improvement in cellular accumulation of antisense DNA was observed through the use of these carriers. In addition, at least a fraction of the transducted DNA appears to be free of entrapment to hybridize to its mRNA target in live cells.

We have shown recently that cell accumulation in culture of antisense DNA is strongly influenced by the presence of a 99mTc-MAG3 group for radiolabeling. We have now compared the in vitro and mouse in vivo behavior of 99mTc when radiolabeled to one antisense phosphorothioate DNA by three different methods. The 18-mer antisense DNA against the RIalpha subunit of PKA was conjugated via a primary amine on the 5'-end with the NHS esters of HYNIC and MAG3 and by the cyclic anhydride of DTPA. Surface plasmon resonance measurements revealed that the association rate constant for hybridization was unchanged for all three chelators as compared with that of the native DNA. Size exclusion HPLC showed rapid and quantitative protein binding for all three chelators upon incubation of labeled DNAs in 37 degrees C serum and cell culture medium. However, in each case, radiolabeled and intact oligonucleotide was still detectable after 24 h. Cellular uptake was tested in an RIalpha mRNA-positive cancer cell line. The order of cellular accumulation of 99mTc was DTPAHYNIC(tricine)MAG3, with the differences increasing with time between 4 and 24 h. The rate of 99mTc egress from cells was found to be MAG3HYNICDTPA, which may explain the order of cellular accumulation. The biodistribution in normal mice was heavily influenced by the labeling method and followed a pattern similar to that seen previously by us for peptides labeled with the same chelators. In conclusion, although these studies concerned only one antisense DNA in one cell line, the results suggest that the success of antisense imaging may depend, in part, on the method of radiolabeling.

To develop a noninvasive direct method for the in vivo tracking of small interfering RNA (siRNA) used in RNA interference, two 18-nucleotide oligoribonucleotides were radiolabeled with technetium-99m ((99m)Tc-RNA). The ability of (99m)Tc-RNA to track delivery was tested in cultured cells and living mice. The cellular delivery of (99m)Tc-RNAs could be quantified by gamma counting and could be visualized by microautoradiography. Radiolabeled RNAs can be efficiently delivered into cells by reaching up to 3x10(5) molecules of small RNAs per cell. Moreover, RNAs were internalized with homogeneous distribution throughout the cytoplasm and nucleus. In tumor-bearing mice, whole-body images and biodistribution studies showed that (99m)Tc-RNAs were delivered to almost all tissues after intravenous injection. The imaging of living animals allowed noninvasive and longitudinal monitoring of the in vivo delivery of these small RNAs. In conclusion, using (99m)Tc radiolabeling, the delivery of small RNAs could be measured quantitatively in cultured cells and could be noninvasively visualized in living animals using a gamma camera. The results of this study could open up a new approach for measuring the in vivo delivery of small RNAs that might further facilitate the development of siRNAs as targeted therapies.

Micronucleus (MN) expression in Peripheral blood lymphocytes is well established as a method to monitor chromosome damage in human populations. The use of MN as a measure of chromosome damage in peripheral blood lymphocytes was first proposed by Countryman and Heddle and subsequently improved with the development of the cytokinesis-block micronucleus (CBMN) method, which has been extensively used to evaluate chromosome damage in human populations. Nevertheless, the CBMN method requires more blood collected by venous puncture, and the procedure detecting MN in cultured lymphocytes is time-consuming. In 1992, a method for MN testing of lymphocytes with human capillary blood collected by skin puncture was developed. The procedure was simple and fast because MNs were detected in non-cultured lymphocytes, and only 1 or 2 drops of capillary blood were needed, so it was called the human capillary blood lymphocytes MN (HCBL-MN) method. The present study gives the comparison of the results of MN frequency in human lymphocytes using the two methods in the same subjects in order to find a simple and sensitive method, to clarify the correlation between the two methods and to provide information on baseline MN frequency in human lymphocytes detected by the two methods.

Efforts are underway to apply strategies developed in connection with antisense chemotherapy to antisense imaging in nuclear medicine. One such strategy is the use of cationic liposome to enhance the cellular uptake of antisense oligonucleotides.Using a 99mTc-labeled 18-mer uniformly phosphorothioate DNA antisense to the mRNA of the RI alpha subunit of PKA, the effects of a cationic liposome as carrier on cell uptake and efflux kinetics in tissue culture was evaluated in a RI alpha mRNA positive ACHN cell line. The sense DNA was used as control.Cell uptake was increased 4-5 fold using the liposome carrier compared to the same dosage of naked DNA. Whether naked or liposome-bound, the antisense DNA showed slower efflux from cells compared to the control, resulting in statistically higher accumulation of the antisense compared to the control DNA and suggesting an antisense effect. The internalization and increased cellular accumulation for both antisense and control DNAs with liposomes were demonstrated by microautoradiography and by subcellular fractionation. Finally, using 99mTc-labeled 15-mer antisense DNA against the c-myc oncogene mRNA in MDA-MB-231 cells, significantly more radiolabel was found in total mRNA for the antisense compared to the sense control DNA, both with and without liposome carrier. In conclusion, in tissue culture, the use of a cationic liposome carrier greatly increased cellular uptake and target mRNA binding of 99mTc-labeled antisense DNA.

Since the 1930s, increased carbohydrate metabolism has been recognized as a feature of malignant cells versus normal cells. 1 This knowledge supplies the rationale for positron emission tomography (PET) imaging of malignant tumors using 2-[18F]-fluoro-2-deoxy-D-glucose (FDG). 2 FDG is a glucose analogue that accumulates in cells in proportion to the rate of glucose metabolism. 3 Hexokinase, as the key enzyme of glucose metabolism, phosphorylates FDG. Once phosphorylated, FDG is metabolically trapped preferentially in tumor cells. 2 In brain tumors and other types of carcinomas (e.g., colon and breast), FDG-PET is used as a diagnostic tool. However, the role of FDG-PET in imaging soft tissue sarcomas has not yet been clarified, and thus FDG-PET is not used routinely in this setting. 4–8 Until now, assessment of soft tissue sarcomas has combined clinical examination with radiologic tomography such as magnetic resonance imaging (MRI) and computed tomography (CT). 9 In primary soft tissue sarcomas, radiologic tomography is a precise method of pathoanatomical imaging, whereas biologic information such as tumor aggressiveness, as reflected by tumor grade or tumor necrosis, cannot be evaluated objectively. Therefore, biopsy is a prerequisite in the preoperative evaluation. Biopsy, however, is invasive and in large tumors is not always representative (due to necrosis and varying tumor grade within a lesion). 9 In the detection of local recurrence, radiologic tomography may be limited because of altered fascial planes, fibrosis, scarring, or tissue edema resulting from previous treatment. 10–13 These considerations make FDG-PET imaging valuable in soft tissue sarcomas. This study analyzes the use of qualitative and semiquantitative FDG-PET imaging in patients suspected of having soft tissue sarcomas, focusing on a functional, noninvasive estimation of tumor grade, identification of viable tumor tissue, and differentiation of local recurrence from benign posttherapeutic tissue alterations.