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The discovery of a two-dimensional electron gas (2DEG) at the [Formula: see text] interface has set a new platform for all-oxide electronics which could potentially exhibit the interplay among charge, spin, orbital, superconductivity, ferromagnetism and ferroelectricity. In this work, by using angle-resolved photoemission spectroscopy and conductivity measurement, we found the reduction of 2DEGs and the changes of the conductivity nature of some ferroelectric oxides including insulating Nb-lightly-substituted [Formula: see text], [Formula: see text] (BTO) and (Ca,Zr)-doped BTO across paraelectric-ferroelectric transition. We propose that these behaviours could be due to the increase of space-charge screening potential at the 2DEG/ferroelectric regions which is a result of the realignment of ferroelectric polarisation upon light irradiation. This finding suggests an opportunity for controlling the 2DEG at a bare oxide surface (instead of interfacial system) by using both light and ferroelectricity.

O-GlcNAcylation (O-GlcNAc) is a posttranslational modification that is mediated by O-GlcNAc-transferase (OGT) and reversed by O-GlcNAcase (OGA). Increasing evidence indicates that protein O-GlcNAcylation is increased in various types of cancer. In the present study, we aimed to evaluate the expression and function of both OGT and OGA in bladder cancer cells in vitro and in vivo. Expression data of OGT and OGA at the mRNA level was obtained from the Oncomine database. Effects of OGT and OGA on cell proliferate, invasive, and migratory abilities were assessed using MTT, wound healing, cell invasive assay, and cell cycle analysis. In vivo assay was also performed in nude mice. The results revealed that the expression of OGT in bladder cancer tissues was higher than that of normal tissues, while the OGA level was found to be lower in cancer tissues. We also found that knockdown of OGT could inhibit cell proliferation, migration, invasion, and induce cell cycle arrest, while these are reversed when OGA is inhibited. We also observed that O-GlcNAcylation could promote tumor formation in vivo, compared with a negative control. In summary, this study describes the oncogenic role of O-GlcNAcylation in bladder cancer cells.

Objective: The aim is to analyze the fracture risk in rheumatic patients by fracture risk assessment tool (FRAX), which is recommended by World Health Organization (WHO), so that we can prevent the occurrence of osteoporotic fracture earlier. Methods: Totally 617 participants, 204 out-patients with rheumatism, 204 in-patients with rheumatism and 209 healthy controls, from March to October in 2018 of Fourth Medical Center of PLA General Hospital, Jishuitan Hospital and China-Japan Friendship Hospital, were enrolled in this study. The probability of hip fracture (PHF) and major osteoporotic fracture (PMOF) in 10 years with FRAX were compared, and the differences between taking sleroids or not and with or without bone mass density (BMD) of femoral neck were evaluated. Correlation analysis was conducted between PHF, PMOF and clinical information, including age, disease duration, gender, steroid usage, osteocalcin, P1NP and β-crosslaps. Results: There was no significant difference in PMOF within 10 years (3.455±2.690 vs 2.973±2.149 vs 3.323±1.828) among the three groups ( P> 0.05), but the PHF (0.986±1.619 vs 0.515±0.873 vs 0.149±0.311) was different ( P< 0.05). PHF and PMOF increased gradually with age. PMOF of patients without glucocorticoid therapy in 10 years was lower than that of patients with glucocorticoid (3.554±2.584 vs 2.857±2.238, P< 0.05). There is no difference between the results of FRAX calculated with BMD or not (3.012±2.231 vs 3.207±2.601, P> 0.05). PHF and PMOF were positively correlated with age, course of disease, glucocorticoid use and osteocalcin level, while PHF was negatively correlated with TP1NP among in-patients. Conclusion: The prevalence of 10-year hip fracture calculated by FRAX in rheumatism patients is higher than that of healthy group. FRAX can be used to calculate fracture risk without BMD. Combination of FRAX and bone turnover markers may be more effective in prediction of osteoporotic fracture in rheumatic patients.

Objective: To investigate the clinical values of colposcopy and cervical biopsy and/or endocervical curettage (ECC) in the diagnosis of cervical lesion. Methods: Clinical data of 128 cases of cervical lesion diagnosed by Xuzhou Cancer Hospital from January 23, 2014 to October 11, 2016 were collected and retrospectively analyzed, all patients underwent colposcopy and cervical biopsy and/or ECC. Results: Among them, the age between 30 to 50 years old were 70 cases, whose transformation zone types of Ⅰ, Ⅱ and Ⅲ were 28 cases (40.0%), 23 cases (32.9%) and 19 cases (27.1%), respectively. The age older than 50 years were 45 cases, whose transformation zone types of Ⅱ and Ⅲ were 1 case (2.2%) and 44 cases (97.8%), respectively. Among the 128 cases of cervical lesions, diagnostic results of colposcopy showed that the chronic inflammation were 57 cases, cervical intraepithelial neoplasia (CIN)Ⅰwere 35 cases, CINⅡor CINⅡ~Ⅲ were 8 cases, CIN Ⅲ were 5 cases and cervical cancer were 23 cases. Alternatively, the pathological results showed that the chronic inflammation were 81 cases, CINⅠwere 17 cases, CINⅡor CINⅡ~Ⅲ were 7 cases, CIN Ⅲ were 5 cases and cervical cancer were 18 cases, respectively. Among the 81 cases of chronic inflammation diagnosed by pathology, 52 cases (64.2%) were consistent with the diagnostic results of colposcopy. Among the 17 cases of low grade squamous epithelial cell lesion (LSIL) diagnosed by pathology, 10 cases were in agree with the diagnostic results of colposcopy. Among the 12 cases of high-grade squamous epithelial cell lesion (HSIL) diagnosed by pathology, 9 cases were concordant with the diagnostic results of colposcopy. Among the 18 cases of cervical cancer diagnosed by pathology, 17 cases were consistent with the diagnostic results of colposcopy. Conclusions: The type of transformation zone is positively correlated with the age, and it can help to choose biopsy and therapeutic manner. The diagnostic accuracies of HSIL and early stage of cervical cancer by multi-point biopsy of colposcopy and/or ECC are high. The cervical lesions which are difficultly found by direct visualization can be identified by colposcopy, and thus provides objective evidence to determine the therapeutic manner for patients with stage ⅡA of cervical cancer.

Objectives: Death risk factors of patients with antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) were explored by the analysis of clinical characteristics of AAV patients, as to provide the basis for early diagnosis and treatment, and reduction of mortality and also improvement of prognosis. Methods: A retrospective study was conducted in patients with AAV which were admitted to this hospital from November 2003 to February 2017, by the contrasts of the similarities and differences of clinical characteristics between the death group and non-death group, for explore the risk factors of death. Results: (1) A total of 66 patients with AAV were included in this study, in which 20 were died (male/female was 12/8), and 46 were still alive, with a total mortality rate of 30.3%.(2)The average age of disease onset in the death group was (67±13) years, which was significantly higher than that of the control group (55±18, P =0.009). (3)The mean value of vasculitis damage index (VDI) in the death group was (6.4±2.5), which was significantly higher than that in the non-death group (4.4±2.5, P =0.006). (4)As to multiple organs involvements among the heart, lung, kidney, gastrointestinal tract, central nervous system and other organs, the proportion of three or more organs involvement in the death group was 85% (17/20), which was significantly higher than that in the control group 47.8%(22/46), P =0.004 8.The incidence of heart murmurs, recent premature beats, aortic insufficiency, chronic heart failure/cardiomyopathy, and massive hemoptysis were significantly higher than those in the control group ( P <0.05). (5) The incidence of infection in the death group (55%) was significantly higher than that in the control group (28.3%, P =0.038). Conclusion: An onset age of more than 65, multiple organs involvement, especially the occurrence of massive hemoptysis, heart valve diseases, heart failure and other cardiovascular involvements, increased VDI and combination of infections are the risk factors of death in AAV patients.

Rice planthopper (RPH) populations of Nilaparvata lugens and Sogatella furcifera periodically have erupted across Asia. Predicting RPH population dynamics and identifying their source areas are crucial for the management of these migratory pests in China, but the origins of the migrants to temperate and subtropical regions in China remains unclear. In particular, their early migration to China in March and April have not yet been explored due to a lack of research data available from potential source areas, Central Vietnam and Laos. In this study, we examined the population dynamics and migratory paths of N. lugens and S. furcifera in Vietnam and South China in 2012 and 2013. Trajectory modeling showed that in March and April in 2012 and 2013, RPH emigrated from source areas in Central Vietnam where rice was maturing to the Red River Delta and South China. Early migrants originated from Southern Central Vietnam (14-16°N), but later most were from Northern Central Vietnam (16-19°N). Analysis of meteorological and light-trap data from Hepu in April (1977-2013) using generalized linear models showed that immigration increased with precipitation in Southern Central Vietnam in January, but declined with precipitation in Northern Central Vietnam in January. These results determined that the RPH originate from overwintering areas in Central Vietnam, but not from southernmost areas of Vietnam. Winter precipitation, rather than temperature was the most important factor determining the number of RPH migrants. Based on their similar population dynamics and low population densities in Central Vietnam, we further speculated that RPH migrate to track ephemeral food resources whilst simultaneously avoiding predators. Migrations do not seem to be initiated by interspecific competition, overcrowding or host deterioration. Nevertheless, S. furcifera establishes populations earlier than N. lugens South China, perhaps to compensate for interspecific competition. We provide new information that could assist with forecasting outbreaks and implementing control measures against these migratory pests.

Objective: Osteosarcoma is one of the most common malignant bone tumors. The mechanisms of osteosarcoma development and invasion have been studied for periods of time, yet targeted therapy for improving survival has not been well established. Histone lysine methyltransferase NSD2 was frequently overexpressed in multiple types of cancer such as multiple myeloma, stomach and colon cancer, and the overexpression of it usually associated with aggressiveness tumor type. However, the expression status and function of NSD2 are still ambiguous in osteosarcoma., Materials and Methods: Here, we evaluate the abnormal expression levels of NSD2 in osteosarcoma samples and cell lines. The higher expression of NSD2 in tumors resulted in a poorer outcome and a worse 5-year overall survival. To investigate the role of NSD2 in osteosarcoma cell proliferation and invasion in vitro, MTT assay, cell cycle distribution, wound healing, transwell assay was performed in relative cell lines, using a recombinant lentivirus expressing NSD2 short hairpin RNA or NSD2 construction., Results: Our results imply that NSD2 promotes osteosarcoma cell proliferation and invasion, and the mechanism was possibly through the suppression of E-cadherin and induction of the epithelial mesenchymal transition, further to proceed invasion of osteosarcoma cells., Conclusions: NSD2 may work as a novel repression of E-cadherin; therefore, NSD2 has potential as a target of OS therapy. In the future, the monitoring of NSD2 in the serum/plasma from the RNA level may be used as a non-invasive method for selecting patients for target therapy.

Objectives: To present the surgical technique of transvesical single-site laparoscopic radical prostatectomy (TVSSLRP) and to evaluate its clinical efficacy. Methods: The clinical parameters of 39 patients who underwent transvesical single-site laparoscopic radical prostatectomy in Department of Urology, Third Affiliated Hospital of Sun Yat-Sen University from November 2010 to June 2015 were retrospectively reviewed. The age was ( M ( Q R )) 64 (10) years (range 47 to 70 years). The median preoperative serum total prostate specific antigen (PSA) level was 7.9 (2.9) μg/L (range 4.2 to 9.8 μg/L). The clinical TNM stage comprised 24 cases of cT1c and 15 cases of cT2a. All the transrectal biopsy Gleason score ≤6. The International Index of Erectile Function (IIEF-5) was (21.7±1.6) points (range 18 to 24 points). The surgical procedures were performed through single-site transvesical approach. The postoperative serum PSA was regularly detected. The continence status were recorded at 1 st month, 3 rd month and 6 th month after catheter removal, and the potencies were evaluated at 3 rd month, 6 th month and 12 th month postoperative, respectively. Results: All the operations were successfully performed and there was no intraoperative complication or conversion to standard laparoscopic approach. The operation duration was (105±26) minuetes, the estimated blood loss was (100±56) ml and no blood transfusion was required. The pathological TNM stage comprised 30 cases of pT2a and 9 cases of pT2b, the Gleason score all ≤6 and no patient had positive surgical margins. The duration of urinary catheterization was (11.6±1.4) days and hospital stay was (12.9±4.3) days. The continence rates were 84.6%, 97.4%, 100% at 1 st month, 3 rd month and 6 th month after catheter removal, respectively. The potency rates were 48.7%, 64.1%, 76.9% at 3 rd month, 6 th month and 12 th month postoperative, respectively, with an IIEF-5 score≥18. Two cases demonstrated biochemical recurrence and one case presented vesico-urethral stricture during an average follow-up of 39 months (range 12 to 60 months). Conclusions: TVSSLRP is suitable for low-risk organ-confined prostate cancer. It can provide satisfactory continence and potency recovery, less complications and good oncological results.

Objective: To investigate the clinical features of patients with antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV), and to explore the disease activity of AAV patients and the relationship with prognosis., Methods: The clinical data of 46 cases of AAV patients in the First Affiliated Hospital of PLA General Hospital were analyzed retrospectively.The clinical and laboratory features of each clinical subtype were compared.The disease activity of AAV and the relationship between disease activity and prognosis were evaluated., Results: Among the 46 patients with AAV, 24 were male, and 22 were female, with the average age of 56±18.Among the subtypes of AAV, the number of granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA) were 22, 17 and 4 respectively, while the positive rate of ANCA are 72.7%, 88.2% and 50.0% respectively.For GPA, the results of ANCA were mainly C-ANCA or ANCA directed toward proteinase-3 (PR3), and for MPA, the results of ANCA were mainly P-ANCA or ANCA directed toward myeloperoxidase (MPO). Upper and lower respiratory disease, renal involvement and non-deformity arthropathy were the common clinical manifestations of all primary AAV subtypes.Epistaxis, nasal blood scab, saddle nose, pulmonary nodule and intrapulmonary cavities were the characteristic manifestations of GPA, while rapid progress of renal failure was prominent in MPA.Whatever their ANCA results, there were no significant differences between each other as to system-organ involvements and laboratory indexes.Seven patients (15.2%) died during hospitalization or in follow-up visits.Serious involvements of heart, lung, kidney, and complicated with infections were the main risk factors of death in AAV patients., Conclusions: Upper and lower respiratory involvements and kidney diseases are the primary manifestations of AAV patients.ANCA results are irrelevant with disease activity and system-organ involvements.Serious involvements of heart, lung, kidney, and complicated with infections are the main risk factors of death in AAV patients.

Classical systems containing cleverly devised combinations of loss and gain elements constitute extremely rich building units that can mimic non-Hermitian properties, which conventionally are attainable in quantum mechanics only. Parity-time (PT) symmetric media, also referred to as synthetic media, have been devised in many optical systems with the ground breaking potential to create nonreciprocal structures and one-way cloaks of invisibility. Here we demonstrate a feasible approach for the case of sound where the most important ingredients within synthetic materials, loss and gain, are achieved through electrically biased piezoelectric semiconductors. We study first how wave attenuation and amplification can be tuned, and when combined, can give rise to a phononic PT synthetic media with unidirectional suppressed reflectance, a feature directly applicable to evading sonar detection.

We examined the expression of peripheral blood natural killer T (NKT) cells in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients and predicted its efficacy after pegylated interferon α-2a (Peg-INFα-2a) therapy. Sixty-three cases of HbeAg-positive CHB inpatients and outpatients, treated in the Third Xiangya Hospital of Central South University from January to December 2010, were administrated Peg-INFα-2a 18 myriad international unit intramuscularly once per week for 48 weeks. The number of peripheral NKT cells, 5 quantitative indicators of hepatitis B, and hepatitis B virus DNA capacity were detected at each time point. Forty-eight weeks after Peg-INFα-2a treatment, 26 HBeAg-positive CHB patients exhibited significant effects, 21 cases exhibited effects, and 16 cases showed no effects. The ratio of peripheral blood NKT cells in T lymphocytes before and 4, 8, and 12 weeks after treatment in the significant effect group was significantly increased compared to the effect group and no effect group (P < 0.01); at the 48th week of treatment and 24 weeks after the drug was withdrawn, NKT cell expression in the significant effect group was significantly higher than that in the effect group (t = 32.0, P < 0.01; t = 27.6, P < 0.01, respectively). A total of 27 patients showed HBeAg seroconversion until the 24th week after drug withdrawal. During treatment with Peg-INFα-2a in HBeAg-positive CHB patients, expression of peripheral blood NKT cells could be used to predict efficacy.

We experimentally investigated concurrent parametric downconversion processes in a two-dimensional hexagonally poled lithium tantalate crystal. The substantial enhancement of parametric gain was observed when concurrent processes shared a common parametric beam. Both degenerate and nondegenerate concurrent parametric downconversion processes were studied. Analyses of the spatial forms and output angles showed a strong dependence on the working temperature, during which a well-defined beamlike parametric output was observed. Our results will stimulate the design for coherent high-gain generation of multiple parametric beams and also shed light on the compact engineering of path-entanglement with specific spatial forms based on concurrent spontaneous parametric downconversion processes.

The heat-shock transcription factor (Hsf) gene CaHsfA2 (GenBank accession No. JX402923) was cloned from the Capsicum annuum thermotolerant line R9 by combining the techniques electron cloning and rapid amplification of cDNA ends. The gene, which is 1436 bp in length, had an open reading frame of 1089 bp that encoded 362 amino acids. There was an 831-bp intron between positions 321 and 322 of the cDNA. The deduced amino acid sequence of CaHsfA2 contained the conserved domains of Hsf, including DNA binding domain, adjacent domain with heptad hydrophobic repeats (A/B), activator motifs, nuclear localization signal, and nuclear export signal, and it had the highest E value of hypothesized annotation of HsfA2. CaHsfA2 had the nearest phylogenetic relationship with HsfA2 from Lycopersicon peruvianum and Mimulus guttatus, which was consistent with its botanical classification. After heat-shock treatment at 40°C for 2 h, the expression of CaHsfA2 was observed in different tissues of thermotolerant cultivar R9 and thermosensitive line B6; however, the expression levels of the CaHsfA2 gene were significantly different as follows: expression in B6 leaf > stem > flower > root, and expression in R9 flower > leaf > stem ≈ root.

The class-3 semaphorins (Sema3A-F, Sema3s) are initially identified to play an important role in axonal guidance and cell migration. Our previous studies showed that Sema3s are also involved in the lymph node metastasis of prostate cancer, and are likely to modulate the behavior of prostate cancer with a pro-tumoral or an anti-tumoral effect, depending on their subtypes. However, no study has critically investigated the value of Sema3s expression in preoperative biopsy samples for the prediction of biochemical recurrence (BCR) after radical prostatectomy. In this study, we evaluated Sema3s expression by immunohistochemistry on 198 prostate biopsies with low- and intermediate-risk localized prostate cancer. The median follow-up was 42 months (range, 6-60) for all patients. Our results showed that Sema3A (OR: 0.19, P<0.001), Sema3B (OR: 0.38, P=0.003), Sema3E (OR: 0.39, P=0.007), and Sema3C (OR: 2.31, P=0.014) staining were independent predictors of BCR on multivariable analysis. Sema3A, 3B, 3C and 3E expression demonstrated potential values in predicting BCR upon survival analysis (P=0.001, P=0.003, P=0.029, P=0.037, respectively, Log-rank test). Our findings suggested that Sema3A, 3B, 3C, and 3E immunostaining in prostate biopsies, as supplements to clinicopathological parameters, could be used for predicting BCR in low- and intermediate-risk prostate cancer patients after radical prostatectomy. Specially, concurrent Sema3C-positive and Sema3A-negative, 3B-negative, 3E-negative staining is associated with an adverse prognosis. Further prospective studies in larger patient populations are needed to validate the current observations.

A new and more comprehensive methodology for reporting outcomes after radical prostatectomy (RP) has been proposed: the so-called pentafecta. However, no prior studies reported intermediate- and long-term pentafecta outcomes after laparoscopic RP. We collected prospectively the clinical data of 170 consecutive patients with a minimum 60-month follow-up undergoing laparoscopic RP for clinically localized prostate cancer. International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form and the Sexual Health Inventory for Men score were used to evaluate the functional outcomes. Logistic regression was used to perform univariable and multivariable analyses. Sixty months after surgery, a pentafecta outcome was achieved by 124 patients (72.9%). On univariable regression analysis, patient age at surgery (P<0.001), body mass index (P=0.031), pathological T stage (P<0.001) and prostate volume (P=0.003) were significantly associated with pentafecta rates. On multivariable analysis, only patient age at surgery (odds ratio 0.95; P=0.006) and pathological T stage (odds ratio 0.82; P<0.001) were independent predictors of pentafecta rates. Using validated questionnaires to assess functional outcomes, for the first time, we evaluated pentafecta outcomes at 5 years after laparoscopic RP. This approach may be beneficial and could be used when counseling patients with clinically localized prostate cancer.

Pulmonary sparganosis mansoni is uncommon in general clinical practice, but prevalent in endemic foci. Pulmonary sparganosis mansoni shares some clinical and radiologic similarities that mimic other common pulmonary pathogens. Delayed diagnosis of pulmonary sparganosis mansoni can pose a significant hazard to the patient. Indeed, a history of ingesting uncooked stone cracks in endemic areas is strongly suggestive of the possibility of pulmonary sparganosis mansoni. We report a case of a 43-year-old male peasant infested with pulmonary sparganosis mansoni who had been misdiagnosed with pulmonary tuberculosis.

We previously reported a noncontact ultrasound water jet indentation system for measuring and mapping tissue mechanical properties. The key idea was to utilize a water jet as an indenter as well as the coupling medium for high-frequency ultrasound. In this paper, the system was employed to assess articular cartilage degeneration, using stiffness ratio as an indicator of the mechanical properties of samples. Both the mechanical and acoustical properties of intact and degenerated bovine patellar articular cartilage (n = 8) were obtained in situ. It was found that the stiffness ratio was reduced by 44 +/- 17% after the articular cartilage was treated by 0.25% trypsin at 37 degrees C for 4 h while no significant difference in thickness was observed between the intact and degenerated samples. A significant decrease of 36 +/- 20% in the peak-to-peak amplitude of ultrasound echoes reflected from the cartilage surface was also found for the cartilage samples treated by trypsin. The results also showed that the stiffness obtained with the new method highly correlated with that measured using a standard mechanical testing protocol. A good reproducibility of the measurements was demonstrated. The present results showed that the ultrasound water jet indentation system may provide a potential tool for the non-destructive evaluation of articular cartilage degeneration by simultaneously obtaining mechanical properties, acoustical properties, and thickness data.

Palpation is a traditional diagnostic procedure for health care professionals to use their fingers to touch and feel the body soft tissues. It is a common clinical approach, though it is rather subjective and qualitative and the palpation results may vary among different people. Tissue ultrasound palpation sensor (TUPS) provides a feasible solution that makes the palpation of soft tissues not subjective feeling any more. It is comprised of an ultrasound transducer together with a load cell to form the finger-sized probe. The probe is used to push against the soft tissue surface to measure the thickness and elasticity of the soft tissues. TUPS has been successfully applied to the assessment of various human tissues. Recently, we have improved TUPS, which can now be linked to personal computer (PC) via universal serial bus (USB) and provide a better user-interface. The information of ultrasound signal and indentation force is displayed on PC in real time during measurement. In this paper, we introduce the recent application of TUPS for the assessment of the transverse carpal ligament. The tissues at the carpal tunnel regions of five normal male subjects were tested using TUPS. The results showed that the average thickness of the tissues covering the carpal tunnel ligament and the tunnel region was 7.98+/-1.05 mm and 9.59+/-1.12 mm, respectively. Under a compression force of 20 N applied by a cylindrical ultrasound indentor with a diameter of 9 mm, the stiffness of the soft tissue layer and the tunnel region was 6.72+/-2.10 N/mm and 15.63+/-8.42 N/mm, respectively. It is expected that TUPS can be a potential tool for non-invasive assessment of carpal tunnel syndrome.

This study is aimed to develop a novel noncontact ultrasonic indentation system for measuring quantitative mechanical properties of soft tissues, which are increasingly important for tissue assessment and characterization. The key idea of this method is to use a water jet as an indenter to compress the soft tissue while at the same time as a medium for an ultrasound beam to propagate through. The use of water jet indentation does not require a rigid compressor in front of the focused high frequency ultrasound transducer to compress the tissue, so that the additional attenuation caused by the rigid compressor and the strong echoes reflected from its surfaces can be avoided. The indentation deformation was estimated from the ultrasound echoes using a cross-correlation algorithm and the indentation force was calculated from the water pressure measured inside the water pipe. Experiments were performed on uniform tissue-mimicking phantoms with different stiffness. The Young's moduli and Poisson's ratios of these phantoms were measured using a uniaxial ultrasound compression system. The ratio of the indentation pressure to the tissue relative deformation was obtained from the water indentation. This ratio was well correlated with the Young's modulus (r = 0.87). The results also demonstrated that the water indentation approach could differentiate materials with different stiffness in a combined phantom (288 kPa and 433 kPa). This novel noncontact water indentation approach could be potentially used for the measurement of the elasticity of small samples and with a fast scanning speed.

A PCR restriction fragment length polymorphism assay was used to analyse single-nucleotide polymorphisms in the tumour necrosis factor (TNF)-alpha and TNF-beta genes of 56 patients with chronic severe hepatitis B virus (HBV) infection, 71 patients who either had chronic mild HBV infection or who were asymptomatic carriers, and 90 healthy controls. The serum TNF-alpha concentrations in patients with chronic severe HBV infection were compared to those of 30 healthy controls by radioimmunoassay. The frequencies of the TNF1/2 genotype and the TNF2 allele were greater in patients with chronic severe HBV infection than in healthy controls (25% vs. 11.1%, p 0.015; 12.5% vs. 5.6%, p 0.036, respectively) and patients with chronic mild HBV infection and asymptomatic carriers (25% vs. 8.8%, p 0.011; 12.5% vs. 4.2%, p 0.015, respectively). Heterozygotes carrying the TNF2 allele had higher levels of serum TNF-alpha than homozygotes for the wild-type allele among all patients with chronic severe HBV infection (p <0.01). The genotype distribution and allele frequency of TNF-beta were similar for patients with chronic severe HBV infection and healthy controls, but the frequency of the TNF-beta*2/2 genotype in patients with chronic mild HBV infection and asymptomatic controls was lower than for healthy controls (9.9% vs. 22.4%, p 0.043) or patients with chronic severe HBV infection (9.9% vs. 26.8%, p 0.043), although this was not significant after correction for multiple testing. It was concluded that TNF-alpha gene polymorphisms may play an important role as a host factor in the progression of HBV infection.

3D ultrasound is a promising imaging modality for clinical diagnosis and treatment monitoring. Its cost is relatively low in comparison with CT and MRI, no intensive training and radiation protection is required for its operation, and its hardware is movable and can potentially be portable. In this study, we developed a portable freehand 3D ultrasound imaging system for the assessment of musculoskeletal body parts. A portable ultrasound scanner was used to obtain real-time B-mode ultrasound images of musculoskeletal tissues and an electromagnetic spatial sensor was fixed on the ultrasound probe to acquire the position and orientation of the images. The images were digitized with a video digitization device and displayed with its orientation and position synchronized in real-time with the data obtained by the spatial sensor. A program was developed for volume reconstruction, visualization, segmentation and measurement using Visual C++ and Visualization toolkits (VTK) software. A 2D Gaussian filter and a Median filter were implemented to improve the quality of the B-scan images collected by the portable ultrasound scanner. An improved distance-weighted grid-mapping algorithm was proposed for volume reconstruction. Temporal calibrations were conducted to correct the delay between the collections of images and spatial data. Spatial calibrations were performed using a cross-wire phantom. The system accuracy was validated by one cylinder and two cuboid phantoms made of silicone. The average errors for distance measurement in three orthogonal directions in comparison with micrometer measurement were 0.06+/-0.39, -0.27+/-0.27, and 0.33+/-0.39 mm, respectively. The average error for volume measurement was -0.18%+/-5.44% for the three phantoms. The system has been successfully used to obtain the volume images of a fetus phantom, the fingers and forearms of human subjects. For a typical volume with 126 x 103 x 109 voxels, the 3D image could be reconstructed from 258 B-scans (640 x 480 pixels) within one minute using a portable PC with Pentium IV 2.4 GHz CPU and 512 MB memories. It is believed that such a portable volume imaging system will have many applications in the assessment of musculoskeletal tissues because of its easy accessibility.

Research in elasticity imaging typically relies on 1-10 MHz ultrasound. Elasticity imaging at these frequencies can provide strain maps with a resolution in the order of millimetres, but this is not sufficient for applications to skin, articular cartilage or other fine structures. We developed a prototype high resolution elastomicroscopy system consisting of a 50 MHz ultrasound backscatter microscope system and a calibrated compression device using a load cell to measure the pressure applied to the specimen, which was installed between a rigidly fixed face-plate and a specimen platform. Radiofrequency data were acquired in a B-scan format (10 mm wide x 3 mm deep) in specimens of mouse skin and bovine patellar cartilage. The scanning resolution along the B-scan plane direction was 50 microm, and the ultrasound signals were digitized at 500 MHz to achieve a sensitivity better than 1 microm for the axial displacement measurement. Because of elevated attenuation of ultrasound at high frequencies, special consideration was necessary to design a face-plate permitting efficient ultrasound transmission into the specimen and relative uniformity of the compression. Best results were obtained using a thin plastic film to cover a specially shaped slit in the face-plate. Local tissue strain maps were constructed by applying a cross-correlation tracking method to signals obtained at the same site at different compression levels. The speed of sound in the tissue specimen (1589.8+/-7.8 m s(-1) for cartilage and 1532.4+/-4.4 m s(-1) for skin) was simultaneously measured during the compression test. Preliminary results demonstrated that this ultrasound elastomicroscopy technique was able to map deformations of the skin and articular cartilage specimens to high resolution, in the order of 50 microm. This system can also be potentially used for the assessment of other biological tissues, bioengineered tissues or biomaterials with fine structures.

Indentation is a commonly used approach to measure the mechanical properties of soft tissues, such as articular cartilage and limb tissues. The Young's modulus of tissue can be calculated from the indentation test using a mechanical model, where the soft tissue is normally assumed to have a flat substrate. In this study, a series of 2D finite element models were established to investigate the effects of bones with various curvatures embedded in the soft tissues during an indentation test. For each curvature of the hard substrate, the errors in the calculation of the Young's modulus were estimated for different indentation depths (0-10%) and aspect ratios a/h of the indentor diameter and the tissue thickness (0.2-2 in seven steps). The radius ratio a/R of the indentor and the curved substrate ranged from 0 to 0.38 in nine steps. Results showed that the error in calculation of the Young's modulus increased by 21.2% when the curvature a/R of the bone increased from 0 to 0.38 (under the condition of a/h=1.0, Poisson's ratio v=0.45). The error increased from 6.0 to 18.2% when the tissue thickness increased from 0.2 to 2 (a/R=0.18, v=0.45). It was found that the error in the Young's modulus calculation caused by the curved hard substrates could be corrected by a single factor for different indentation depths. This factor depends on the Poisson's ratio, the aspect ratio a/h and the radius ratio a/R.

Background: Vasoconstrictor and vasodilator release from vascular endothelial cells not only regulates vascular tone but also induces vascular smooth muscle cell proliferation., Methods: In order to understand the role of vasoconstrictor and vasodilator release in the development of hypertension in spontaneously hypertensive rats (SHR), aortic endothelial cells were isolated and cultured from 4-week-old and 24-week-old SHR (SHR-4 and SHR-24) and age-matched Wistar-Kyoto rats (WKY-4 and WKY-24) used as control. Prostacyclin (PGI2), endothelin-1 (ET-1) and thromboxane A2 (TXA2) release from cultured endothelial cells in the culture medium, were measured after 30 min with or without treatment with acetylcholine, calcium ionophore A23187 or thrombin., Results: The results showed that there was no significant difference in ET-1 secretion between SHR-4 and age-matched WKY rats, but ET-1 secretion was about twice as high in SHR-24 as in WKY-24. TXA2 secretion was significantly higher in SHR-4 than in WKY-4 and was also higher than in SHR-24, but there was no significant difference between SHR-24 and WKY-24. The secretion of PGI2 was higher in SHR-24 than in WKY-24 and also higher than in SHR-4 and WKY-4. The prostaglandin PGI2 and TXB2 secretions from all groups of cultured VECs treated with various reagents, acetylcholine, calcium ionophore A23187 or thrombin were increased in similar patterns. However, there was no significantly different response between SHR and WKY VECs., Conclusions: Similar levels of ET-1 secreted from endothelial cells between SHR-4 and WKY-4 indicated that ET-1 secretion seems not a crucial factor in early hypertension development in SHR. The high level of TXA2 secretion in SHR-4 may involve in early hypertension development in SHR.

Objective: To investigate the inhibitory effect of the combination of 2,3-dihydroxypropyl-adenine (DHPAs) and hyperbaric oxygen (HBO) on Japanese B encephalitis virus infection in mice., Methods: Mice infected P3-55 and P3-53 virus were used in the experiments. Virus was inoculated intraperitoneally to Kumming strain mice (8.5-9.5 g). Mice were divided into groups and treated in the incubation period of the infection. The duration of treatment was 5 days, and the experiments were terminated at the end of 2 weeks after treatment. The living and the dead were then counted finally., Results: The intergroup comparison showed marked difference between the control group and combination of DHPAs and hyperbaric oxygen group (P < 0.025 and P < 0.01), but there was no statistical difference between other groups and the control group (P > 0.05)., Conclusion: The combined treatment of (S) DHPA and/or (RS)-DHPA and HBO has inhibitory effect on Japanese encephalitis virus infection in experimental mice.

Dietary fat has previously been shown to have somewhat complicated relationships to levels of oxidative stress in rats. In this study, we examined the effects of five different dietary fat intakes on levels of oxidative DNA damage in rats. Animals fed diets containing 3%, 5%, 10%, or 15% corn oil had body weights that were similar after 20 weeks. Animals fed a 20% fat diet, however, had significantly higher mean body weight than any other group. Levels of 5-hydroxymethyl-2'-deoxyuridine, one marker of oxidative DNA damage, had different relationships to dietary fat in blood and mammary gland. In blood, levels increased with dietary fat levels, and the highest levels were observed with the 20% fat diet (65% higher levels than with the 3% fat diet). In mammary gland, a plateau-type effect was observed, with maximal levels of oxidative DNA damage being obtained using 10% fat (representing a 68% increase relative to the 3% fat diet). This could be a result of induction of compensatory mechanisms in response to a high-fat diet in mammary gland but not in the short-lived nucleated blood cells. Oxidative DNA damage levels in blood thus appear to be a marker of dietary fat intake. In mammary gland, however, levels of DNA damage are consistent with previously observed promotional effects of dietary fat on mammary gland tumorigenesis at lower levels of fat intake with little or no incremental promoting effects at higher levels of fat intake.

Methylazoxymethanol (MAM), an aglycone of cycasin extracted from Cycad seed, is reported to induce microencephaly in rats after prenatal or postnatal administration. Forty postnatal day (PND) 1 rats derived from 8 timed-pregnant rats were used to evaluate the effect of a single subcutaneous injection of MAM on PND 1 on cell proliferation in rat brain. All dams were fed NIH-31 diet. In the MAM-treated group, each pup received a single injection of MAM at 10 mg/kg body weight. In the control group, pups were injected with saline solution. Body weight of pups was recorded on PNDs 1, 7, 14, 21, 28, and 60. One male pup in each litter was removed for sacrifice by decapitation on PNDs 7, 14, 21, 28, and 60. The brain was removed and dissected to obtain the brain stem, caudate nucleus, cerebellum, frontal cortex, hippocampus, hypothalamus, and olfactory bulb. The percentage (%) of S-phase cells in the cell cycle for each region was measured as index of cell proliferation. A significant (p<0. 05) reduction in body weight was detected on PND 7. The % S-phase cells in cerebellum on PND 7 and olfactory bulb on PND 14 initially increased and then later decreased. There were significant decreases in the % S-phase cells in both cerebellum and caudate nucleus on PND 21 and olfactory bulb on PND 28. No significant changes were found in other brain regions in cell proliferation activity between the control and MAM-treated groups. The % of S-phase cells in cerebellum decreased 65% on PND 60 but lacked statistical significance due to small number of animals used in each group. The results indicated that a single injection of MAM at 10 mg/kg/body weight on PND 1 inhibited cell proliferation in the cerebellum in a manner that could lead to microencephaly.

The unique cytokeratin K19 specifically expresses in simple epithelial cells, basal cells of non-keratinized stratified squamous epithelium, epidermal cells during the embryonic stage and squamous carcinoma cells, but it is not expressed in adult epidermis. Interestingly, when epidermal cells are cultured in vitro, K19 is re-expressed in the supra-basal layer. K19 expression was used as a marker for epidermal cell growth and differentiation. In order to clarify the temporal and spatial sequential expression in cultured keratinocyte, two-stage human keratinocyte culture systems were used to examine K19 expression in keratinocytes in a proliferation and differentiation stages through immunoblotting and immunohistochemistry assay. According to our results, K19 was not expressed in cultured human keratinocytes in the proliferation stage but was re-expressed in keratinocytes three days after the cultured medium was changed to a differentiation medium. Immunohistochemical observation revealed that K19 was persistently expressed in the supra-basal layer of cultured keratinocytes during first three weeks of culturing, but none was detectable in the basal cell layer. When keratinocytes were cultured with an "inserted cultured dish," K19 was persistently expressed in all layers of keratinocytes nourished by medium both from an inner chamber and an outer chamber. The different expression of K19 in these two different culture systems seemed to indicate that down regulation of K19 expression in keratinocyte was related to the direction of medium supply.

OBJECTIVE:To study the relationship between the expression of p53 and c-erbB-2 proteins and biologic behaviors of human mucoepidermal carcinoma.METHODS:The expressions of oncogene proteins p53 and c-erbB-2 in 32 cases of human mucoepidermal carcinomas were investigated with microwave immunohistochemistry.RESULTS:p53 and c-erbB-2 oncoproteins in duct epithelial cells around cancer tissues were 10.0% and 15.0%,respectively,but those in the acinar cells affiliated with the salivary gland ducts were negative. The positive rates of p53 oncoprotein and c-erbB-2 oncoprotein in mucoepidermal carcinoma were 40.6% and 46.9%,respectively. Both p53 and c-erbB-2 oncoproteins were expressed in mucous cells,epidermoid cells and intermediate cells of mucoepidermal carcinoma. The expression of p53 and c-erbB-2 oncoproteins in human mucoepidermal carcinoma tissues were related to histological patterns,differentiation degree of cancer and tumor recurrence (P<0.01).CONCLUSION:This study suggested that both p53 and c-erbB-2 on coproteins,as the markers for differentiation of cancer,might be useful in screening progress and evaluating prognosis of patients with mucoepidermal carcinoma.

The effects of dietary fat and age on the level of malondialdehyde (MDA), a product of lipid peroxidation, were investigated in cerebellum, kidney, and liver tissues of female Fischer 344 rats. Groups of rats were fed diets containing various levels of corn oil (3, 5, 10, 15, or 20%), starting at 57 days of age, for a duration of 2, 10, or 20 weeks. High fat diets are thought to promote tumor formation, diabetes, and cardiovascular diseases via induction of oxidation stress, and this can begin early in the lifespan. However, it was observed that rats chronically consuming 3 and 5% corn oil diets yielded significantly higher levels of MDA, as analyzed by high-performance liquid chromatography, compared with those fed higher fat diets. After 20 weeks of feeding, the concentration of MDA in each of the three organs studied showed no significant differences among rats consuming diets containing 10, 15, or 20% corn oil. The levels of MDA were highest in the cerebellum, followed by kidney, and lowest in liver. Over the 20-week feeding period, a decrease in MDA level in both cerebellum and liver was observed.

Spontaneously hypertensive (SHR), Wistar-Kyoto (WKY), and Sprague-Dawley (SD) rats at the ages of 4, 8, 12, 16 and 24 weeks were used to examine the effects of age on the density of endothelin-1 (ET-1) binding sites in aortic smooth muscle cells and systolic blood pressure (SBP). The SBP of the 3 different rat strains was measured, and the maximum binding value (Bmax) and dissociation constant (Kd) of ET-1 binding sites in smooth muscle cells of the thoracic aorta were determined. The results showed that the SBP and Bmax values of SHR, WKY and SD rats increased with age; the SBP and Bmax value at each corresponding age were significantly higher in SHR than in WKY and SD rats, however, there was no significant difference between WKY and SD rats. The relationship of age vs SBP, age vs Bmax, and Bmax vs SBP showed significantly positive correlation in all 3 rat strains. The regression line in the Bmax of endothelin binding sites against SBP in the 3 different rat strains presented a similar slope. These results indicate that SBP, which increased with age, could be related to an increased density of ET-1 binding sites on vascular smooth muscle cells in these 3 different rat strains.

The effect of a food-restricted diet on the fecal microflora of rats was studied by determining total anaerobic bacteria, bacterial cellular fatty acids, and the predominant intestinal bacteria shown by polymerase chain reaction (PCR) primers specific for the 16S rRNA gene sequences of 12 bacterial species. Twenty-four female Fischer 344 rats, 57 days old were divided into two groups and maintained on an NIH-31 diet. One group was fed ad libitum while the other group received 60% of ad libitum food intake (40% food restriction supplemented with vitamins and minerals equal to the ad libitum animals). After 2, 10, and 20 weeks on this dietary regimen, groups of four animals were sacrificed and the intestinal contents analyzed for changes in the bacterial flora. The anaerobic population for two-week (short-term) food-restricted rats was 3.2 x 10(8) per gram, slightly less than the 9.1 x 10(8) per gram found in the ad libitum-fed rats. The anaerobic populations in 20-week food restricted and ad libitum fed rats were 1.9 x 10(9) and 2.7 x 10(9) per gram, respectively. The total anaerobic population did not change significantly in either group during the 20-week study. No statistically significant differences were observed in the bacterial cellular fatty acid profiles between the two groups as determined by gas-liquid chromatography. PCR analysis of the intestinal contents indicated no significant shifts in the predominant flora due to dietary changes. The results, using three different methods to detect changes in the rat intestinal microflora, suggest that long-term dietary restriction had little effect on the microflora of female Fischer 344 rats.

Endothelin-1 (ET-1), which is secreted from vascular endothelial cells, is not only a potent vasoconstrictor but also a vascular smooth muscle cell growth factor. The direct effect of ET-1 on vascular smooth muscle cells, mediated via its specific receptor may therefore play an important role in hypertension and atherosclerosis. Our previous studies indicated that ET-1 secretion from cultured aortic endothelial cells from spontaneously hypertensive rats (SHRs) at the prehypertensive stage (4 weeks old) was not significantly different from that of cells from age-matched Wistar-Kyoto (WKY) rats. In this study, the binding of ET-1 to cultured aortic smooth muscle cells from SHRs and WKY rats was studied. Using tissue explant techniques, rat aortic smooth muscle cells from SHRs and age-matched WKY rats of different ages (4 and 24 weeks old) were successfully cultured in vitro. The maximum binding capacity (Bmax) and binding affinity (Kd) of ET-1 to cultured aortic smooth muscle cells were evaluated by a receptor-binding assay. The data revealed that the affinity of ET-1 binding to smooth muscle cells was similar in all 4 groups of experimental rats. However, the Bmax of cultured smooth muscle cells from 24-week-old SHRs was 2.5 times higher than of smooth muscle cells from age-matched WKY rats (8.64 +/- 0.72 vs 3.69 +/- 0.10 fmol/10(6) cells) and 1.5 times higher than in aortic smooth muscle cells from 4-week-old SHRs (8.64 +/- 0.72 vs 5.36 +/- 0.36 fmol/10(6) cells). These results suggest that hypertension in SHRs may be related to a high density of ET-1 receptors on arterial smooth muscle cells.

The effect of L-triiodothyronine (L-T3)-induced hyperthyroidism on reproduction in female rats was studied. Treatment groups used were normal control, 1, 2, 4, 8, and 16 micrograms L-T3/100 g body weight (b.w.)/day. Subcutaneous injections of L-T3 began the first day of estrus until day 1 or day 19 of lactation. All rats given 1, 2, or 4 micrograms L-T3 had regular estrous cycles and normal number of pregnancies. Levels of L-T3 at 8 or 16 micrograms results in abnormal estrous cycles. Only one pregnancy occurred in the 8 micrograms group and no rats became pregnant in the 16 micrograms group. While groups on 1 or 2 micrograms L-T3 had normal parturition, groups on 4 micrograms or more showed signs of dystocia. Only the 1 microgram L-T3 group lactated to day 20, but at 67% of normal control. All levels above 1 micrograms showed loss of pups by day 2 of lactation due to lack of milk production, loss of maternal behavior, and cannibalism. Mammary gland wet and dried fat-free tissue (DFFT) weights were decreased in all treated groups except 1 microgram L-T3. The wet and DFFT weights of thyroids and uteri on days 2 or 20 of lactation were not altered by L-T3 treatment, but levels above 1 microgram increased both wet and DFFT weights of adrenal glands and ovaries. The data indicate that the no observed adverse effect level (NOAEL) of L-T3 for female rat reproduction would be below 1 microgram/100 g b.w./day. L-T3 treatment at 1 microgram/100 b.w./day or above is detrimental. These effects may be mediated through a hormonal imbalance due to the accelerated metabolic rate in reproductive tissues associated with hyperthyroidism.

In the present study, we successfully established a "tissue explant technique" to obtain high yield and purity of endothelial cells from the aorta of hypertensive and normotensive rats (SHR and WKY). Small pieces of aorta were placed on fibronectin precoated petri dishes. The effects of oxygenation in the tissue preparation stage, tilting of the petri dish during the explanting period and timing of the removal of tissue blocks from petri dishes were evaluated. These procedures appeared to be critical for cell survival, tissue adhesion and minimizing of non-endothelial cell contamination. The cultured endothelial cells were characterized by morphological, immunohistochemical and biochemical examination. The cultured cells from both SHR and WKY rats showed similar endothelial cell character, positive immunofluorescence staining for the von Willebrand factor, and uptake of acetylated low-density lipoprotein (DiI-ac-LDL). The secretory function of prostacylcin I2 (PGI2), thromboxane A2 and endothelin of cultured endothelial cells was measured. The results showed that the secretion of both PGI2 and endothelin was greater in SHR than in WKY rats, but that there was no difference in thromboxane A2 secretion. Therefore, our "tissue explant technique" can provide high yield and purity of endothelial cells with their specific biological function in vitro. It will permit us to further study the role of endothelial cells in the development of hypertension.

Thyroxine secretion rates (TSR) at various stages of pregnancy in rats were measured by the radiothyroxine pool-turnover method. Groups of rats included normal controls (non-pregnant), days 5, 10, 20, and 22 of pregnancy and near term (within 24 hours prior to parturition if past 22 days of pregnancy). Each animal had blood samples taken just prior to injection of 10 microCi L-thyroxine (L-T4)-131I and at 12, 24, 36, and 48 hours afterwards. Determinations of thyroxine iodine (T4-I), volume of distribution (VD), fractional turnover rate (K), and L-T4 pool size were made from these samples. TSR was calculated as the product of (1.54) (T4-I) (VD) (K). An increase in TSR occurred near term, 3.65 micrograms L-T4/day compared to 1.23 micrograms L-T4/day in the controls, was primarily due to an increase in VD from 33.9 ml in the controls to 90.0 ml near term. A rapid increase in TSR to 3.65 micrograms L-T4/day just prior to term was postulated to be due to a stimulatory action of relaxin in the presence of estrogen upon L-T4 utilization. The mechanism of the increase in TSR in pregnant rats is probably due to the effect of several hormonal changes in maternal tissues throughout pregnancy and to adaptation of the pregnant animals to higher metabolic needs of the rapid developing fetuses.

Based on the assumption that a conserved differentiation program governs the assembly of sarcomeres in skeletal muscle in a manner analogous to programs for viral capsid assembly, we have defined the temporal and spatial distribution of 10 muscle-specific proteins in mononucleated myoblasts as a function of the time after terminal cell division. Single cells in mitosis were identified in monolayer cultures of embryonic chicken pectoralis, followed for selected time points (0-24 h postmitosis) by video time-lapse microscopy, and then fixed for immunofluorescence staining. For convenience, the myoblasts were termed x-h-old to define their age relative to their mitotic "birthdate." All 6 h myoblasts that emerged in a mitogen-rich medium were desmin+ but only 50% were positive for a alpha-actin, troponin-I, alpha-actinin, MyHC, zeugmatin, titin, or nebulin. By 15 h postmitosis, approximately 80% were positive for all of the above proteins. The up-regulation of these 7 myofibrillar proteins appears to be stochastic, in that many myoblasts were alpha-actinin+ or zeugmatin+ but MyHC- or titin- whereas others were troponin-I+ or MyHC+ but alpha-actinin- or alpha-actin-. In 15-h-old myoblasts, these contractile proteins were organized into nonstriated myofibrils (NSMFs). In contrast to striated myofibrils (SMFs), the NSMFs exhibited variable stoichiometries of the sarcomeric proteins and these were not organized into any consistent pattern. In this phase of maturation, two other changes occurred: (1) the microtubule network was reorganized into parallel bundles, driving the myoblasts into polarized, needle-shaped cells; and (2) the sarcolemma became fusion-competent. A transition from NSMFs to SMFs took place between 15 and 24 h (or later) postmitosis and was correlated with the late appearance of myomesin, and particularly, MyBP-C (C protein). The emergence of one, or a string of approximately 2 mu long sarcomeres, was invariably characterized by the localization of myomesin and MyBP-C to their mature positions in the developing A-bands. The latter group of A-band proteins may be rate-limiting in the assembly program. The great majority of myoblasts stained positively for desmin and myofibrillar proteins prior to, rather than after, fusing to form myotubes. This sequential appearance of muscle-specific proteins in vitro fully recapitulates myofibrillar assembly steps in myoblasts of the myotome and limb bud in vivo, as well as in nonmuscle cells converted to myoblasts by MyoD. We suggest that this cell-autonomous myoblast differentiation program may be blocked at different control points in immortalized myogenic cell lines.

Hepatic parenchymal cells in most adult mammals are polyploid, with most of the cells in the quiescent or low-proliferation state. Polyploidization has been related to carcinogenesis and aging, and both end points are significantly affected by dietary restriction (DR). Direct measures of hepatic nuclear polyploidization in DR B6C3F1 mice have not been examined. We examined the effect of DR on distributions of nuclear ploidy in both sexes and on different age groups of B6C3F1 mice. Differences between young and old male mice and between old male and female mice were also compared. Hepatic nuclear ploidy values were measured by flow cytometry. The DNA histograms were analyzed for the percentage of nuclei having different classes of DNA content by gating channels between the areas under the peaks of diploid, tetraploid, and octaploid. The results indicate that 1 or 26 months of DR started at 4 months of age did not alter hepatic nuclear ploidy distributions in young and old mice. Our data suggest that in the male mouse, polyploidization is established by 5 months of age for hepatic nuclei and that ploidy classes are affected by sex at 30 months of age. For females, effects in the octaploid nuclei are seen as a result of DR.

While the life-extending and disease-modulating effects of caloric restriction (CR) are well documented in whole animal studies and in correlative experiments using cells taken from CR animals, very few studies have used cells in culture after their removal from the CR-fed animal. In using this in vivo-->in vitro approach we have attempted to examine the proposition that the effects of CR can be transferred to individual cells by analyzing the cellular functions of proliferation and transformation, the activation of oncogenes, and the methylation of DNA as a function only of diet. Pancreatic acinar cells excised from CR-fed Brown-Norway rats and placed in rich medium showed different responses compared to cells from ad libitum (AL)-fed controls. CR had the effect of slowing growth rate and protecting against spontaneous and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced transformation over 14 passages of cells in culture. At the molecular level, cells from the CR animals showed reduced c-Ha-ras oncogene expression and mutation as well as reduced mutation of the p53 suppressor gene. CR also increased genomic methylation of ras DNA. We conclude that the effects of CR treatment of the animal are transferred to individual cells and note that these responses (decreased proliferation and transformation; depressed oncogene expression and mutation and decreased suppressor gene mutation; and increased oncogene methylation) are cellular and molecular analogs of in vivo weight loss, life extension, and carcinogenesis modulation, which are hallmarks of CR in the whole animal. The fact that these responses are seen generations after the cells are removed from the CR-treated animal indicates that CR causes a permanent predisposition of pancreatic acinar cells to these modulated responses and shows the value of the in vivo-->in vitro protocol in studies that relate diet to cellular and molecular function.

Localizations of CEA,EMA and keration in 19 cases of mucoepidermal carcinomas were investigated using the indirect immunoperoxidase technique.The results showed CEA was negative in normal salivary glands and showed faint reaction in glands near carcinoma tissue.Keratin and EMA were localized in some myoepithelial cells.The positive rates in carcinoma tissue were 78.9%,89.5% and 84.2%,respectively.The positive rates and staining intensity of CEA and EMA in carcinoma tissue gradually decreased with the decline of tumor differentitation,but that of keratin showed no variation.the author consider that CEA and EMA could become good indices in clinically diagnosing mucoepithelial carcinoma and determining tumor differentiation type cell in mucoepidermal carcinoma and have a potential to multiply express the tumor elements of epithelium and/or mesenchyma.

Young adult male Fischer rats maintained on a reduced calorie diet (60% of ad libitum food consumption) for 6 weeks showed a decrease in the binding of aflatoxin B1 (AFB1) to hepatic or renal nuclear DNA and a reduction of AFB1-induced hepatocellular damage. Repeated dosing of rats with AFB1 resulted in the inhibition of hepatic and renal DNA synthesis measured by [3H]thymidine incorporation. However, the rate of DNA synthesis was greater in ad libitum (AL) rats than in calorically restricted (CR) animals. Three days after AFB1 dosing, the rate of DNA synthesis had recovered to the control level. Cell cycle analyses measured by a flow cytometric method on kidney cells of both AL and CR rats showed that there were no significant changes in cell populations in the S phase between these two groups of rats. AFB1 inhibited the cell proliferation on an average of 33%. The restoration of the cell proliferation in kidney cells was found on the third day after AFB1 dosing. The rate of the regenerative cell proliferation was found to be slightly greater in AL rats than in CR animals. The AFB1-induced regenerative DNA synthesis in both liver and kidney was retarded by CR.

The effect of dietary restriction (DR) on cell proliferation determined by cell cycle analysis in tissues of young and old mice was investigated. Using the percentage of S-phase cells as an index of cell proliferation, we found that DR inhibited cell proliferation in spleen and thymus in young mice. No significant changes were found in bone marrow and kidney in the ad libitum (AL) or DR mice regardless of age. In old mice, the DR effect was observed in spleen only. When age increased, a parallel decline in cell proliferation was evidenced by a reduced % of S-phase cells. DR produces a greater cell cycle effect in the young mice than in the old mice. The present data suggests that inhibition of cell proliferation by DR may be affected by type of tissue, age, length of DR, and capacity or rate of cell proliferation.

Increased fat and caloric content of the diet has been associated with increased mammary tumor incidence. The dietary modulation of cellular redox state may be one mechanism behind this association. We have examined the effects of changes in dietary fat and caloric intake on the levels of 5-hydroxymethyluracil in DNA from rat liver and mammary gland. Female Fischer 344 rats, 40 days old, were maintained on 3% (low-fat), 5% (control), or 20% (high-fat) corn oil diets for 2 weeks. A fourth group of rats had the same daily fat intake as the control group, but total caloric intake was restricted by 40%. As a measure of oxidative DNA damage, 5-hydroxymethyluracil levels were measured in the DNA extracted from liver and mammary gland by gas chromatography-mass spectrometry. 5-Hydroxymethyluracil levels in the liver DNA of the low-fat, high-fat, and calorie-restricted groups were decreased relative to that of control, but the only significant decrease was in the calorie-restricted group (p less than 0.01). In the mammary gland DNA, statistically significant decreases in damage were found in each group relative to control (p less than 0.05). The relationship between fat in the diet and oxidative stress is thus complex. These results show that changes in dietary intake of both fat and calories can modulate oxidative DNA damage levels, and the effect of diet was more clearly evident in the DNA from mammary gland than in DNA from liver.

Experiments are described supporting the proposition that the assembly of stress fibers in non-muscle cells and the assembly of myofibrils in cardiac cells share conserved mechanisms. Double staining with a battery of labeled antibodies against membrane-associated proteins, myofibrillar proteins, and stress fiber proteins reveals the following: (a) dissociated, cultured cardiac myocytes reconstitute intercalated discs consisting of adherens junctions (AJs) and desmosomes at sites of cell-cell contact and sub-sarcolemmal adhesion plaques (SAPs) at sites of cell-substrate contact; (b) each AJ or SAP associates proximally with a striated myofibril, and conversely every striated myofibril is capped at either end by an AJ or a SAP; (C) the invariant association between a given myofibril and its SAP is especially prominent at the earliest stages of myofibrillogenesis; nascent myofibrils are capped by oppositely oriented SAPs; (d) the insertion of nascent myofibrils into AJs or into SAPs invariably involves vinculin, alpha-actin, and sarcomeric alpha-actinin (s-alpha-actinin); (e) AJs are positive for A-CAM but negative for talin and integrin; SAPs lack A-CAM but are positive for talin and integrin; (f) in cardiac cells all alpha-actinin-containing structures invariably are positive for the sarcomeric isoform, alpha-actin and related sarcomeric proteins; they lack non-s-alpha-actinin, gamma-actin, and caldesmon; (g) in fibroblasts all alpha-actinin-containing structures are positive for the non-sarcomeric isoform, gamma-actin, and related non-sarcomeric proteins, including caldesmon; and (h) myocytes differ from all other types of adherent cultured cells in that they do not assemble authentic stress fibers; instead they assemble stress fiber-like structures of linearly aligned I-Z-I-like complexes consisting exclusively of sarcomeric proteins.

The effect of dietary restriction (DR) on the proportion of cells in various phases of the cell cycle as determined by flow cytometry was investigated in the bone marrow and kidney of young and old Fischer 344 rats. Control rats were fed a standard occurrence of numerous age-associated diseases, including cancer, renal diseases and by the control rats starting at 16 weeks of age until killed at 5 or 20 months old. The relative proportion of cells in the various phases of the cell cycle was independent of tissue type, treatment condition and age, consistently showing an order of G1- greater than S- greater than G2M-phase. In old rats DR did not affect cell cycling in bone marrow of either sex, however, it did cause an increase in the percentage of G1-phase cells in the kidney of male rats. Additionally, DR caused a mathematically significant change in the percentage of cells in all phases of the cell cycle in the bone marrow of young male rats but had no effect in young females. The percentage of S-phase cells in both tissues of both sexes decreased in old rats when compared to young rats regardless of treatment conditions, indicating a parallel decline in cell proliferating activity with aging. To summarize, DR produces a greater cell cycle effect in the young male than the old male rats. Proliferative capacity is enhanced when the young male rats are dietary restricted. This may aid in DNA repair mechanisms and/or immune system response.

Cultured cardiac myocytes were stained with antibodies to sarcomeric alpha-actinin, troponin-I, alpha-actin, myosin heavy chain (MHC), titin, myomesin, C-protein, and vinculin. Attention was focused on the distribution of these proteins with respect to nonstriated myofibrils (NSMFs) and striated myofibrils (SMFs). In NSMFs, alpha-actinin is found as longitudinally aligned, irregular approximately 0.3-microns aggregates. Such aggregates are associated with alpha-actin, troponin-I, and titin. These I-Z-I-like complexes are also found as ectopic patches outside the domain of myofibrils in close apposition to the ventral surface of the cell. MHC is found outside of SMFs in the form of discrete fibrils. The temporal-spatial distribution and accumulation of the MHC-fibrils with respect to the I-Z-I-like complexes varies greatly along the length of the NSMFs. There are numerous instances of I-Z-I-like complexes without associated MHC-fibrils, and also cases of MHC-fibrils located many microns from I-Z-I-like complexes. The transition between the terminal approximately 1.7-microns sarcomere of any given SMF and its distal NSMF-tip is abrupt and is marked by a characteristic narrow alpha-actinin Z-band and vinculin positive adhesion plaque. A titin antibody T20, which localizes to an epitope at the Z-band in SMFs, precisely costains the 0.3-microns alpha-actinin aggregates in ectopic patches and NSMFs. Another titin antibody T1, which in SMFs localizes to an epitope at the A-I junction, typically does not stain ectopic patches and NSMFs. Where detectable, the T1-positive material is adjacent to rather than part of the 0.3-microns alpha-actinin aggregates. Myomesin and C-protein are found only in their characteristic sarcomeric locations (even in just perceptible SMFs). These A-band-associated proteins appear to be absent in ectopic patches and NSMFs.

Ovaries of tadpoles, froglets, young frogs, and mature frogs of Rana catesbeiana were cut into small pieces. They were incubated for 6 hr in Krebs-Ringer bicarbonate buffer as controls. Another series of ovaries of the same developmental stages were incubated with pituitary extracts in the buffer as experimentals. Media were then analyzed for estradiol secretion by radioimmunoassay. The results showed that estradiol secretion by tadpole ovaries during development was not affected by the addition of pituitary extracts of mature frogs in the media at any stage while those of young and mature frogs with pituitary extracts secreted more estradiol than those without. These findings indicate that tadpole ovaries are unresponsive to pituitary agents to produce estradiol while frog ovaries are dependent on some pituitary hormones to synthesize estradiol. Thus frog ovaries acquire dependence on the pituitary agent only after metamorphosis.

The microsomal activation of the potent hepatocarcinogen aflatoxin B1 (AFB1) and the expression of selected protooncogenes were investigated in the livers of rats exposed to delta 9-tetrahydrocannabinol (THC). At equimolar levels of cytochrome P-450, the microsome-mediated binding of AFB1 to DNA was significantly lower (56% of the controls) in preparations from drug exposed rats. Hepatic expression of the c-k-ras protooncogene was 3-fold higher in THC exposed animals. These results suggest the possible occurrence of long lasting residual effects in the rats exposed to THC.

Dehydroepiandrosterone (DHEA) a naturally occurring steroid, has been reported to inhibit the binding of N-dimethylnitrosamine and 7,12-dimethylbenz[a]anthracene to DNA in vivo and to increase glutathione transferase activity. In this study, we have investigated if DHEA could protect hepatic DNA from damage by the potent hepatocarcinogen aflatoxin B1 (AFB1). Young male Fischer 344 (2-month-old) rats were fed a diet containing 0.8% DHEA for 14 days. Control rats were pair-fed the same diet without DHEA. The rats were then administered a single i.p. dose of [3H]AFB1 in dimethylsulfoxide (0.6 mg/kg body weight; 200 mCi/mmol) and killed after 3 h. Liver weight, mitochondrial, microsomal and cytosolic protein, cytochrome P450 content and glutathione transferase activity increased significantly (P less than 0.001) in DHEA-fed rats; however, the hepatic DNA content was not altered. DHEA feeding increased the total amount of AFB1 bound to hepatic protein but decreased the extent of DNA binding. In in vitro experiments, there was less total binding to DNA and protein by AFB1 when using microsomes from DHEA-fed rats. These results suggest that DHEA inhibits the binding of AFB1 to DNA by modifying the biotransformation of the carcinogen.

Ethylenethiourea (ETU) was given by gavage at a dose of 40 mg/kg/day from Days 7 through 15 of gestation to hypothyroid and euthyroid rats, and to rats given exogenous thyroxine, to determine whether ETU teratogenicity occurs through alteration of maternal thyroid function. At sacrifice on Day 20 of gestation 84-100% of the fetuses in all groups given ETU were malformed regardless of the thyroid status of the dams. Ten percent of the fetuses of dams thyroparathyroidectomized at 75 days of age that were not given ETU were malformed; no malformations were noted among the fetuses of the other groups not given ETU. Hence, ETU was found to induce teratogenicity in rats but not through alteration of maternal thyroid status. In addition, it was determined that ETU lowered serum thyroxine concentration, that hypothyroidism itself increased the background level of malformations in the rat, and that hypothyroidism qualitatively and quantitatively increased the incidence of specific malformations after ETU administration.