Roles of DWI and T2-weighted MRI volumetry in the evaluation of lymph node metastasis and lymphovascular invasion of stage IB-IIA cervical cancer

AIM

To determine whether magnetic resonance imaging volumetry on T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) could be used to assess lymph node metastases (LNM) and lymphovascular invasion (LVSI) in resectable cervical cancer.

MATERIAL AND METHODS

Sixty-five consecutive patients with cervical cancer were enrolled retrospectively. Tumour size, including maximum transverse diameter, tumour length, and gross tumour volume (GTV), was evaluated on DWI and T2WI. Apparent diffusion coefficient (ADC) values were measured. Univariate, multivariate, and receiver operating characteristic (ROC) curve analyses were performed to determine whether tumour size and ADC could be used to assess LNM and LVSI.

RESULTS

Tumour length on both T2WI and DWI, and T2WI-based and DWI-based GTVs could be used to assess LNM (p=0.002, 0.004, 0.001, and <0.001, respectively). Tumour length on T2WI, T2WI-based GTV, DWI-based GTV, and ADC value could be used assess LVSI (p=0.039, 0.038, 0.012, 0.039, respectively). Multivariate analyses showed both T2WI-based GTV (odds ratio [OR] = 1.044; p=0.008) and DWI-based GTV (OR=1.941; p=0.019) were independent risk factors for LNM. T2WI-based GTV (OR=1.023, p=0.038) and DWI-based GTV (OR=3.275, p=0.008) were independent risk factors for LVSI. No statistically significant difference was identified between the area under the ROC curve (AUC) of the DWI-based GTV and the T2WI-based GTV (0.790 versus 0.775, p=0.113), or the tumour length on both T2WI (0.790 versus 0.734, p=0.185) and DWI (0.790 versus 0.737, p=0.333) for LNM. For LVSI, the AUC of DWI-based GTV was higher than T2WI-based GTV (0.720 versus 0.682, p=0.006).

CONCLUSION

GTV on both T2WI and DWI could be used assess LNM and LVSI. DWI-based GTV might show the greatest potential for assessing LNM and LVSI in resectable cervical cancer.

Early prediction of response to neoadjuvant chemotherapy using contrast-enhanced ultrasound in breast cancer

Early prediction of non-response is essential in order to avoid inefficient treatments. The objective of this study was to determine the contrast-enhanced ultrasound (CEUS) for early predicting pathologic complete response (pCR) to neoadjuvant chemotherapy (NAC) in breast cancer patients.Between March 2018 and October 2019, 93 consecutive patients with histologically proven breast cancer scheduled for NAC were enrolled. Conventional ultrasound and CEUS imaging were performed before NAC and after two cycles of NAC. CEUS parameters were compared with pathologic response. Multiple logistic regression analyses were utilized to explore CEUS parameters to predict pCR, and receiver operating characteristic analysis was used to evaluate the predictive ability.Therapeutic response was obtained from 25 (27%) patients with pCR and 68 (73%) with non-pCR. Compared to non-pCR, pCR cases have a significantly higher proportion of homogeneous enhancement feature (56% vs 14%, P < .001) and centripetal enhancement (52% vs 23%, P = .012). A significant decrease in peak intensity (PI) was observed after two cycles of NAC. Compared with non-pCR patients, the kinetic parameters PI change (PI%) was higher in pCR patients (P < .001). Multiple logistic regression demonstrated two independent predictors of pCR: internal homogeneity (odds ratio, 4.85; 95% confidence interval: 1.20-19.65; P = .027) and PI% (odds ratio, 1.08; 95% confidence interval: 1.02-1.15; P = .007). In receiver operating characteristic curve analysis, internal homogeneity and PI%, with area under curve of 0.71 and 0.84, predicted pCR with sensitivity (56%, 95%) and specificity (85%, 70%), respectively.Internal homogeneity and PI% of CEUS may be useful in the noninvasive early prediction of pCR in patients with breast cancer.

Ultrasound and Clinical Characteristics of False-negative Results in Mammography Screening of Dense Breasts

OBJECTIVE

We analyzed the clinical and ultrasound characteristics associated with false-negative mammography results in women with dense breasts.

MATERIALS AND METHODS

The present study included 191 women (mean age, 54.47 ± 11.61 years; range, 31-75 years) who had presented from July 2015 to June 2018 with pathologically confirmed breast cancer. The mammography, conventional ultrasound, and elastography imaging results of these patients were reviewed. Breast density and screening cancer probability from mammography and conventional ultrasound imaging were scored using the Breast Imaging Reporting and Data System. Multivariate logistic regression analysis was performed to identify the factors independently associated with the false-negative results on breast mammographic screening.

RESULTS

Of 191 confirmed breast cancer cases, 55 (28.8%) were assigned to category ≤ 3, and 136 (71.2%) were assigned to category ≥ 4a according to the mammography findings. All the breasts were graded mammographically as dense. A rougher margin (odds ratio [OR], 8.123; 95% confidence interval [CI], 1.731-38.127) was the strongest independent factor associated with negative results, followed by a lower stiffness ratio (OR, 7.773; 95% CI, 2.574-23.473), negative axillary lymph node status (OR, 5.066; 95% CI, 1.028-24.955), and softer lesions (OR, 1.037; 95% CI, 1.001-1.075).

CONCLUSION

Women with dense breasts, a lower lesion/glandular tissue stiffness ratio, and softer cancer can easily lead to a misdiagnosis using mammography. By giving sufficient attention to the margin, earlier stage cancer with negative lymph node status are more likely to benefit from supplemental ultrasound imaging.

Usefulness of Strain Elastography, ARFI Imaging, and Point Shear Wave Elastography for the Assessment of Crohn Disease Strictures

OBJECTIVES

The aim of this study was to evaluate the diagnostic performance of strain elastography, acoustic radiation force impulse (ARFI) imaging and point shear wave elastography (p-SWE) for assessment of the predominant types of intestinal stenosis in Crohn disease.

METHODS

Twenty-five patients were enrolled in this study, among whom 25 suspicious stenoses in 25 intestinal segments were studied using gray scale ultrasonography. All 3 elastography methods were performed, and all patients underwent endoscopy within 24 hours with pathologic biopsy. The sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), Youden index, and area under the receiver operating characteristic curve (AUROC) were calculated. Pathologic findings were regarded as the gold standard.

RESULTS

For SE, the optimal cutoff value was a score of 4 or greater (sensitivity, 75%; specificity, 66.7%; accuracy, 68%; PPV, 30%; NPV, 93.3%; AUROC, 0.708; however, P > .05). The results of ARFI imaging were similar: the optimal cutoff value was a score of 4 or greater (sensitivity, 50%; specificity, 81%; accuracy, 76%; PPV, 33.3%; NPV, 89.4%; AUROC, 0.669; P < .05). However, for p-SWE, the optimal cutoff value was reached when the shear wave velocity exceeded 2.73 m/s (sensitivity, 75%; specificity, 100%; accuracy, 96%; PPV, 100%; NPV, 95.5%; AUROC, 0.833; P < .05).

CONCLUSIONS

p-SWE had the best performance for evaluating and differentiating intestinal stenosis in Crohn disease, while neither SE nor ARFI imaging achieved satisfactory outcomes for evaluating inflammatory stenosis and fibrotic stenosis of Crohn disease.

[An assessment of the sublingual immunotherapy with Dermatophagoides farinae on asthma control level and pulmonary function of allergic asthma and rhinitis in adult patient]

Objective:To evaluate the efficacy, asthma control level and pulmonary function of sublingual immunotherapy on allergic asthma and rhinitis in adult patient. Method:This retrospective analysis of 182 cases of adult patient from 18-60 years with allergic asthma and rhinitis, according to the patients' wishes they were divided into drug group（66 patients） and SLIT group（116 patients）. Drug group patients were treated with low to moderate doses of inhaled corticosteroids+long-acting β2 receptor agonists and mometasone furoate nasal spray+desloratadine tablets as symptomatic treatment. SLIT group was treated by SLIT with Dermatophagoides farina drops on this basis. Before treatment and 1 year, 2 year and 3 years after treatment, the ACT, PEF%, DASS, NASS, TNSS and TMS were evaluated. Result:The ACT, PEF%, DASS, NASS, TNSS and TMS had continuously improved significantly 1 year, 2 year and 3 years after treatment in both groups comparing with baseline（P<0.05）. Compared with 1 year after treatment, SLIT group had lower ACT, PEF%, DASS, NASS, TNSS and TMS in 2 years after treatment（all P<0.05）, whereas drug group had lower TMS and DASS（all P<0.05）. In 3 years of treatment, only SLIT group resulted in significant continuous improvement in DASS and TMS（all P<0.05）. After 1 year, 2 and 3 years of treatment, SLIT group resulted in significantly better ACT, PEF%, DASS, NASS and TMS than drug group（all P<0.05）. After 2 and 3 years of treatment, TNSS of SLIT group were significantly lower than in drug group（P<0.05）. Conclusion:Sublingual immunotherapy for 3 yearswith Dermatophagoides farinae dropsin adult patient with allergic asthma and rhinitis was more effective than drug therapy alone, and asthma control and lung function improved significantly.

Benign lesion evaluation: Factors causing the "stiff rim" sign in breast tissues using shear-wave elastography

OBJECTIVE:

To investigate the factors causing the "stiff rim" sign in breast lesions using shear-wave elastography.

METHODS:

A total of 907 patients with 907 lesions were included retrospectively in this study. Traditional ultrasound and shear-wave elastography imaging were both performed. Patients age, maximum diameter, depth, distance, echogenicity, shape, boundary, margin, internal components, CDFI, calcification, echogenicity attenuation and longitudinal growth of lesions were observed and calculated by both univariate and multivariate analyses.

RESULTS:

Univariate analyses indicated that the age, depth, shape, margin, internal components, CDFI, calcification and pathology showed significant difference between the benign lesions with and without a "stiff rim", whereas there was no correlation of "stiff rim" with maximum diameter, distance, boundary, echogenicity, echo attenuation and longitudinal growth of the lesions. Multivariate analysis expressed that CDFI, margin, internal components, depth and age were significantly associated with the "stiff rim" sign in breast benign lesions, whereas there was no correlation with the pathology, shape or calcification of the lesions.

CONCLUSIONS:

The "stiff rim" sign can be helpful for differentiation between benign and malignant lesions. Older patients with a "stiff rim" sign whose benign masses are deep, poorly defined, heterogeneous and have a positive CDFI should be examined more closely to avoid unnecessary false-positives.

ADVANCES IN KNOWLEDGE:

The "stiff rim" sign can be helpful for differentiation between benign and malignant lesions. Positive CDFI, poorly defined margin, heterogeneous internal components, deep depth and older age were significantly associated with the "stiff rim" sign in benign breast lesions.

Association of conventional ultrasound, elastography and clinicopathological factors with axillary lymph node status in invasive ductal breast carcinoma with sizes > 10 mm

Background

To evaluate whether conventional ultrasound, elastography [conventional strain elastography of elasticity imaging, acoustic radiation force impulse induced strain elastography of virtual touch tissue imaging, and a novel two-dimensional shear wave elastography of virtual touch tissue imaging quantification] and clinicopathological factors are associated with axillary lymph node metastasis in invasive ductal breast carcinoma with sizes > 10 mm.

Materials and Methods

We evaluated 150 breast lesions from 148 patients using the above methods and the clinicopathological factors. Univariate and multivariate logistic regression analysis were performed to determine the axillary lymph node metastasis risk factors. Diagnostic performance was evaluated using receiver operating characteristic curve analysis.

Results

Sixty-three tumors (42%) were node-positive, 87 (58%) were node-negative. Aspect ratio, virtual touch tissue imaging grade, shear wave velocity, pathological invasive tumor size, and histological grade maintained independent significance in predicting nodal involvement. The mean tumor shear wave velocitys (4.60, 6.49, 7.16) increased in proportion to metastatic node number (0, 1-3, ≥ 4, respectively; P < 0.001). For all tumors in this study, the cut-off shear wave velocity was 6.16 m/s and was associated with 64.1% sensitivity, 78.0% specificity and an area under the ROC curve of 0.799 (95% confidence interval, 0.731-0.868).

Conclusions

Aspect ratio, virtual touch tissue imaging grade, shear wave velocity, pathological invasive tumor size and histological grade are independently associated with axillary lymph node metastasis in invasive ductal breast carcinoma with sizes > 10 mm.

Occupational metal exposures, smoking and risk of diabetes and prediabetes

BACKGROUND

Metal exposure and tobacco smoking have been independently associated with diabetes, but no study has been conducted to investigate the interaction between them on the risk of diabetes.

AIMS

To investigate the effect of occupational exposure to metals, and potential effect modification by smoking, on the risk of diabetes and prediabetes in a cohort of Chinese male workers.

METHODS

We assessed metal exposure and tobacco smoking at baseline in the Jinchang Cohort of male workers. We used Poisson regression analyses to estimate the interaction between smoking and metal exposures based on occupations, which we grouped according to the measured urinary metal levels.

RESULTS

Among the 26008 study subjects, compared with non-smokers, the adjusted prevalence ratio (PR) for diabetes was 1.8 [95% confidence interval (CI) 1.3-2.4] for smokers of >40 pack-years. The adjusted PRs were 1.2 (95% CI 1.1-1.4) among mining/production workers and 2.7 (95% CI 2.4-3.0) among smelting/refining workers, both compared with office workers. There was significant effect modification under the additive model between smoking and metal exposure on the prevalence of diabetes (Pinteraction = 0.001), with an adjusted PR of 3.6 (95% CI 2.4-5.4) for those with >40 pack-years of smoking who had the highest metal exposures, whereas no significant interaction was observed for prediabetes.

CONCLUSIONS

Both exposure to metals and heavy smoking were associated with an increased prevalence of diabetes in this large cohort of male workers. There was also strong interaction between these two exposures in affecting diabetes risk that should be confirmed in future studies.

Comparison of Virtual Touch Tissue Quantification and Virtual Touch Tissue Imaging Quantification for diagnosis of solid breast tumors of different sizes

BACKGROUND

Acoustic radiation force impulse imaging (ARFI) with Virtual Touch Tissue Quantification (VTQ) or Virtual Touch Tissue Imaging Quantification (VTIQ) measures shear wave velocity (SWV), which is proportional to tissue stiffness, a diagnostic parameter for malignancy.

OBJECTIVE

To compare the performance of VTQ and VTIQ in diagnosing solid breast tumors.

METHODS

Conventional ultrasound, VTQ and VTIQ were used to examine 246 solid breast tumors from 230 patients. Tumors were grouped according to size: <10 mm, 10-20 mm, >20 mm. Pathological diagnoses were via histological examination of biopsies. ROC curves were used to assess diagnostic performance and optimal cut-off points for VTQ and VTIQ.

RESULTS

For all sizes, SWVVTQ and SWVVTIQ were higher for malignant versus benign tumors (P < 0.05). SWVVTQ and SWVVTIQ were both higher for tumors≥10 mm (P < 0.05). Areas under the ROC curves (diagnostic performance index; 0.860-0.952) did not differ significantly between VTQ and VTIQ. Optimal cut-off values for SWVVTQ and SWVVTIQ were higher for tumors≥10 mm.

CONCLUSION

The diagnostic performance of VTQ and VTIQ was moderate to good for solid breast tumors. Although both methods have higher sensitivities in tumors≥10 mm, their overall diagnostic performance was similar for all sizes.

A novel two-dimensional quantitative shear wave elastography to make differential diagnosis of breast lesions: Comprehensive evaluation and influencing factors

BACKGROUND

Virtual touch imaging quantification (VTIQ), a form of shear wave elastography, may help in the diagnosis of breast lesions.

OBJECTIVE

We aimed to evaluate the diagnostic performance of combined VTIQ and conventional ultrasound (US), and assess the factors influencing VTIQ measurement.

METHODS

From September 2014 to December 2014, 162 patients with breast lesions were examined by US and VTIQ to assess shear wave speed (SWS) and morphological characteristics (lesion shape, orientation, margin and echo pattern). The sensitivity, specificity and accuracy of VTIQ, US and VTIQ+US for the diagnosis of breast lesions was evaluated in comparison to pathological results. Factors influencing deviations in SWS measurements were assessed by logistic regression.

RESULTS

The SWS cut-off between malignant and benign lesions was 3.73 m/s. The sensitivity, specificity and accuracy were: 98.07%, 55.96%, and 69.57% for US; 76.92%, 78.89% and 78.26% for VTIQ; and 98.07%, 84.40% and 88.82% for US+VTIQ. The two factors that influenced the SWS results were the lesion margin (odds ratio [OR], 16.363; 95% confidence interval [CI], 3.220-29.020) and vascularity (OR, 6.712; 95% CI, 1.358-9.072).

CONCLUSIONS

The lesion margin and vascularity could affect the measurement of SWS as well as the experience of examiner. However, VTIQ is still a reliable method that provides valuable information in the differential diagnosis of breast lesions, and may reduce unnecessary biopsies.

Controlling condensate collapse and expansion with an optical Feshbach resonance

We demonstrate control of the collapse and expansion of an (88)Sr Bose-Einstein condensate using an optical Feshbach resonance near the (1)S(0)-(3)P(1) intercombination transition at 689 nm. Significant changes in dynamics are caused by modifications of scattering length by up to ± 10a(bg), where the background scattering length of (88)Sr is a(bg) = -2a(0) (1a(0) = 0.053 nm). Changes in scattering length are monitored through changes in the size of the condensate after a time-of-flight measurement. Because the background scattering length is close to zero, blue detuning of the optical Feshbach resonance laser with respect to a photoassociative resonance leads to increased interaction energy and a faster condensate expansion, whereas red detuning triggers a collapse of the condensate. The results are modeled with the time-dependent nonlinear Gross-Pitaevskii equation.

Frequent SLIT2 Promoter Methylation in the Serum of Patients with Ovarian Cancer

OBJECTIVE: The slit homologue 2 ( SLIT2) gene is a tumour suppressor gene. This study investigated the methylation status of the SLIT2 promoter in women with ovarian cancer in terms of identifying whether this might aid the early diagnosis of ovarian cancer. METHODS: Using methylation-specific polymerase chain reaction analysis, the methylation status of the SLIT2 promoter was measured in tumour tissue and serum samples from 36 patients with ovarian cancer and in matched serum samples from 25 controls without cancer. RESULTS: Aberrant methylation of the SLIT2 promoter was present in ovarian tissue from 29/36 (80.6%) ovarian cancer patients, but not in the 25 healthy controls. Among the cases with hypermethylation in their ovarian tissue, 27/29 (93.1%) of the case-matched serum DNA samples, including all four cases of early-stage ovarian cancer, showed hypermethylation of the SLIT2 promoter. CONCLUSIONS: Hypermethylation of the SLIT2 promoter may be a relatively early event in ovarian cancer; thus, its detection may be an effective approach to improve early diagnosis.

Spontaneous spin textures in dipolar spinor condensates

We have mapped out a detailed phase diagram that shows the ground state structure of a spin-1 condensate with magnetic dipole-dipole interactions. We show that the interplay between the dipolar and the spin-exchange interactions induces a rich variety of quantum phases that exhibit spontaneous magnetic ordering in the form of intricate spin textures.

Structural phase transitions of vortex matter in an optical lattice

We consider the vortex structure of a rapidly rotating trapped atomic Bose-Einstein condensate in the presence of a corotating periodic optical lattice potential. We observe a rich variety of structural phases which reflect the interplay of the vortex-vortex and vortex-lattice interactions. The lattice structure is very sensitive to the ratio of vortices to pinning sites and we observe structural phase transitions and domain formation as this ratio is varied.

Quantum phases of dipolar spinor condensates

We study the zero-temperature ground state structure of a spin-1 condensate with magnetic dipole-dipole interactions. We show that the dipolar interactions break the rotational symmetry of the Hamiltonian and induce new quantum phases. Different phases can be reached by tuning the effective strength of the dipolar interactions via modifying the trapping geometry. The experimental feasibility of detecting these phases is investigated. The spin-mixing dynamics is also studied.

Diffraction of a superfluid fermi gas by an atomic grating

An atomic grating generated by a pulsed standing-wave laser field is proposed to manipulate the superfluid state in a quantum degenerate gas of fermionic atoms. We show that in the presence of atomic Cooper pairs, the density oscillations of the gas caused by the atomic grating exhibit a much longer coherence time than that in the normal Fermi gas. Our result indicates that the technique of a pulsed atomic grating is a potential candidate to detect the atomic superfluid state in a quantum degenerate Fermi gas.

Antiproliferative activity of REIC/Dkk-3 and its significant down-regulation in non-small-cell lung carcinomas

We recently reported the cloning of the REIC/Dkk-3 gene, whose expression was shown to be down-regulated in many human immortalized and tumor-derived cell lines [T. Tsuji et al. (2000) Biochem. Biophys. Res. Commun. 268, 20-24]. In the present study, we demonstrated that expression of the exogenous REIC/Dkk-3 gene in tumor cells inhibited cell growth. Furthermore, the level of REIC/Dkk-3 mRNA in normal human cells was lowest in the late G(1) phase during the cell cycle. Then we found that the expression of REIC/Dkk-3 was significantly down-regulated in surgically resected non-small-cell lung carcinomas. We determined the REIC/Dkk-3 locus on chromosome 11p15, where loss of heterozygosity has frequently been observed in human tumors. These findings indicate that REIC/Dkk-3 may function as a tumor suppressor.

The in vivo role of p38 MAP kinases in cardiac remodeling and restrictive cardiomyopathy

Stress-induced mitogen-activated protein kinase (MAP) p38 is activated in various forms of heart failure, yet its effects on the intact heart remain to be established. Targeted activation of p38 MAP kinase in ventricular myocytes was achieved in vivo by using a gene-switch transgenic strategy with activated mutants of upstream kinases MKK3bE and MKK6bE. Transgene expression resulted in significant induction of p38 kinase activity and premature death at 7-9 weeks. Both groups of transgenic hearts exhibited marked interstitial fibrosis and expression of fetal marker genes characteristic of cardiac failure, but no significant hypertrophy at the organ level. Echocardiographic and pressure-volume analyses revealed a similar extent of systolic contractile depression and restrictive diastolic abnormalities related to markedly increased passive chamber stiffness. However, MKK3bE-expressing hearts had increased end-systolic chamber volumes and a thinned ventricular wall, associated with heterogeneous myocyte atrophy, whereas MKK6bE hearts had reduced end-diastolic ventricular cavity size, a modest increase in myocyte size, and no significant myocyte atrophy. These data provide in vivo evidence for a negative inotropic and restrictive diastolic effect from p38 MAP kinase activation in ventricular myocytes and reveal specific roles of p38 pathway in the development of ventricular end-systolic remodeling.

Ferromagnetism in a lattice of Bose-Einstein condensates

We show that an ensemble of spinor Bose-Einstein condensates confined in a one-dimensional optical lattice can undergo a ferromagnetic phase transition and spontaneous magnetization arises due to the magnetic dipole-dipole interaction. This phenomenon is analogous to ferromagnetism in solid state physics, but occurs with bosons instead of fermions.

Helicobacter pylori induces pepsinogen secretion by rat gastric cells in culture via a cAMP signal pathway

Infection with Helicobater pylori (H. pylori) is associated with various stomach diseases such as chronic gastritis, peptic ulcer, and gastric carcinoma. In order to investigate the mechanisms of enhanced production of pepsinogen by H. pylori in cultured rat gastric cells that have the potential to produce pepsinogen, secretion and synthesis of pepsinogen in the cells exposed to H. pylori extract were determined by measuring the hydrolysis of hemoglobin. Various drugs were used to study the mechanisms of effects of H. pylori on the cells. Exposure of the gastric cells to H. pylori extract caused a significant increase in pepsinogen secretion into the culture medium within 30-180 min in a dose-dependent manner, accompanied by a significant increase in pepsinogen synthesis in the gastric cells after 60 min of incubation. Heat treatment of the H. pylori sonicate at 100 degrees C for 10 min completely abolished the stimulatory effect of H. pylori on pepsinogen secretion. 2',3'-Dideoxyadenosine (50 microM), a specific adenylate cyclase inhibitor, abolished the effect of H. pylori-induced pepsinogen secretion. Puromycin (10 microg/ml), a protein synthesis inhibitor, and nicorandil (0.1 mM), a specific intracellular calcium antagonist, reduced the H. pylori-induced pepsinogen secretion by 37% (p<0.01) and 25% (p<0.05), respectively. On the other hand, actinomycin D (1 microg/ml), an RNA synthesis inhibitor, did not affect the H. pylori-induced pepsinogen secretion. Consequently, dibutyryl cAMP potentially stimulated the pepsinogen secretion from gastric epithelial cells in a dose-dependent manner. H. pylori induces pepsinogen secretion and synthesis by gastric epithelial cells through an increase in the intracellular cAMP and mobilization of the intracellular calcium. In addition, H. pylori affects pepsinogen synthesis at the translational level.

[Pharmacological comparison between virosecurinine and securinine]

Pharmacological activities of virosecurinine (Vse) and securinine (Sec) were studied. The results showed that acute toxicity of Vse was 1/13.6 that of Sec, and Vse had no convulsive effects on rats or frogs, while Sec had. The results also showed that Vse and Sec could elevate blood pressure and excite respiration in cats.

Effects of oxygen concentrations on human fibroblasts treated with Fe(3+)-NTA

Free radicals derived from the reaction of iron and oxygen are thought to be one of the causes of tissue injury. In order to identify whether oxygen concentrations are an important factor in iron-mediated damage to cells, cytotoxic effects of Fe(3+)-NTA on human fibroblasts (KMST-6 line) were studied under the conditions of 1% and 20% oxygen concentrations in an incubator. A comparison of the effects of Fe(3+)-NTA on cells cultured in 1% and 20% oxygen environments showed that the following features were more prominent under the usual culture concentrations of 20% oxygen: i) cytotoxicity, ii) increase in intracellular reactive oxygen species, iii) increase in H(2)O(2) production in the cells, and iv) formation of 8-hydroxydeoxyguanosine. To elucidate the roles of endogenous antioxidants, the levels of manganese superoxide dismutase (MnSOD) and catalase were measured by Western blotting. The increase in MnSOD in the presence of Fe(3+)-NTA was greater under the condition of 20% O(2) than under the condition of 1% O(2). The expression of catalase was significantly up-regulated at 20% O(2). However, when the cells were treated with Fe(3+)-NTA, the expression of catalase was markedly down-regulated under the condition of 20% O(2). Hydroxyl radical scavengers such as vitamin E, dimethyl-sulfoxide (DMSO) and mannitol reduced endogenous ROS generation and alleviated the cytotoxic effects of iron. On the other hand, superoxide dismutase (SOD), vitamin C and catalase did not show any protective effects against Fe(3+)-NTA. These findings suggest that enhanced cytotoxic effects of Fe(3+)-NTA at 20% O(2 )are due to endogenously produced hydroxyl radicals.

A family of depsi-peptide fungal metabolites, as selective and competitive human tachykinin receptor (NK2) antagonists: fermentation, isolation, physico-chemical properties, and biological activity

Four tachykinin (NK2) receptor inhibitors, SCH 378161 (1), SCH 217048 (2), SCH 378199 (3), and SCH 378167 (4) were isolated from the fermentation broth of a taxonomically unidentified fungus. These compounds were separated from the fermentation broth by ethyl acetate extraction. Purification and separation of the individual compounds were achieved by NK2 assay-guided fractionation using gel filtration, reverse phase chromatography and HPLC. They were identified to be a family of depsipeptides by spectroscopic and degradation studies. Compounds 1 and 3 contain proline and differ as an amide and acid whereas 2 and 4 contain pipecolic acid and differ in being an amide and acid. All of these compounds contain an identical hydroxy acid. They are selective NK2 inhibitors with Ki values ranging from 27-982 nM and demonstrate no activity at 10 microM in the NK1 and NK3 assays. In addition, compounds 1 and 2 inhibited NKA-induced increases in the concentration of intracellular Ca2+, [Ca2+]i, in a CHO cell expressing the human NK2 receptor; this inhibition was competitive in nature with pA2 values of 7.2 and 7.5, respectively. These data demonstrate that these natural products are selective and competitive receptor antagonists of the human NK2 receptor.

Eliminating the mean-field shift in two-component bose-einstein condensates

We demonstrate that the nonlinear mean-field shift in a multicomponent Bose-Einstein condensate may be eliminated by controlling the two-body interaction coefficients. This modification can be achieved by engineering the environment of the condensate. We consider the case of a two-component condensate in a quasi-one-dimensional atomic waveguide, achieving modification of the atom-atom interactions by varying the transverse wave functions of the components. Eliminating the density-dependent phase shift represents a promising potential application for multicomponent condensates in atom interferometry and precision measurements.

Creating macroscopic atomic Einstein-Podolsky-Rosen states from Bose-Einstein condensates

We present a scheme for creating quant entangled atomic states through the coherent spin-exchange collision of a spinor Bose-Einstein condensate. The state generated possesses macroscopic Einstein-Podolsky-Rosen correlation and the fluctuation in one of its quasispin components vanishes. We show that an elongated condensate with large aspect ratio is most suitable for creating such a state.

Species selectivity of a small molecule antagonist for the CCR1 chemokine receptor

The species specificity of a small molecule antagonist for the human CCR1 chemokine receptor, 2-2-diphenyl-5-(4-chlorophenyl)piperidin-1-yl)valeronitrile (CCR1 antagonist 1), has been examined using cloned CCR1 receptors from various species. The compound was able to bind to rabbit, marmoset, and human CCR1, and was able to block the functional activation of these receptors. However, it failed to significantly displace radiolabeled macrophage inflammatory protein-1alpha (MIP-1alpha) binding to mouse CCR1 at concentrations up to 10 microM. These data suggested that the antagonist binding site is well-conserved in rabbit, marmoset and human CCR1, but not in mouse CCR1. The functional selectivity and mechanism of action for CCR1 antagonist 1 were further characterized. CCR1 antagonist 1 blocked the increase in intracellular Ca(2+) stimulated by CCR1 agonists, but had no effect on N-formyl-Met-Leu-Phe (FMLP), monocyte chemotactic protein-1 (MCP-1) and stromal-derived factor 1alpha (SDF1alpha)-induced Ca(2+) mobilization, demonstrating functional selectivity for CCR1. Since CCR1 antagonist 1 is a functional antagonist of marmoset and rabbit CCR1 receptors, it should be possible to test its efficacy in animal models of disease.

Growth inhibitory effects of ATP and its derivatives on human fibroblasts immortalized with 60Co-gamma rays

In our previous study (Katayama B et al, Int J Mol Med 2: 603-606, 1998), cell growth inhibition caused by ATP added to cultures was found to be greater in immortalized human fibroblasts than in the normal human fibroblasts. Since it has been reported that ATP affects cells via P2-purinergic receptors, growth inhibitory effects of ATP and its derivatives on immortalized human fibroblasts were investigated in the present study in order to learn what type of receptors are involved in ATP cytotoxicity. The ATP derivatives used in this study were: ATP, ADP, beta, gamma-methyleneadenosine 5'-triphosphate (MeATP), 2' & 3'-o-(4-benzoylbenzoyl) adenosine, triethylammonium salt (BzATP), adenosine 5'-o-(3-thiotriphosphate) (ATPgammaS), 2-methylthioadenosine 5'-triphosphate (2-MeSATP) and UTP. The extent of cytotoxicity induced by these drugs was found to be in the order of: ATP=ADP>ATPgammaS>MeATP=BzATP. On the other hand, neither 2-MeSATP nor UTP showed any cytotoxicity. These findings indicate that ATP may exert the cell growth inhibition by certain kinds of signal transduction via P2x or P2y purinergic receptors which affect intrinsic channels/pores of cell membrane and/or G protein activation. As a result, intracellular elevation in the concentrations of ions such as calcium and potassium, membrane depolarization, loss of endogenous ions/metabolites, and activation of inositol phospholipid-specific phospholipase C may occur. Actually, a dihydropyridine calcium channel blocker, nifedipine, and an ATP-sensitive K+-channel blocker, glybenclamide, reduced the growth inhibitory effects of ATP on the cells to some extent. The growth inhibition caused by ATP was not due to apoptosis or induction of a cyclin/CDK kinase inhibitor, P21.

Yeast functional assay of the p53 gene status in 11 cell lines and 26 surgical specimens of human hepatocellular carcinoma

The structural abnormalities of the p53 gene have frequently been detected in hepatocellular carcinomas (HCCs). To ascertain whether or not functional inactivation of this gene also occurs in HCCs, the transactivation of p53 gene products in 11 HCC cell lines maintained in our laboratory and 26 HCC surgical specimens was examined by yeast functional assay (functional analysis of separated alleles in yeast: FASAY), which determines the functional status of the individual p53 alleles. The p53 gene product was inactivated in 8 of 11 (72.7%) HCC cell lines and in 12 of 26 (46.2%) HCC surgical specimens. The inactivation frequency of the gene was 37.5%, 36.4%, and 71.4% in well, moderately, and poorly differentiated HCCs, respectively. In HCC surgical specimens larger than 5 cm in diameter, the inactivation frequency was 83.3% while in those smaller than 2. 5 cm, it was 14.3%. These results show that functional inactivation of p53 gene products often occurs in HCCs and that the inactivation frequency of the gene in HCCs is well correlated with differentiation degree and tumor size, suggesting that the inactivation of p53 gene products plays a role in progression from well to poorly differentiated HCC.

[Determination of trace barium in biological samples by Zeeman graphite AAS with coated graphite tube]

Using a tungstate-coated graphite tube, trace barium in biological samples was determined by Zeeman graphite AAS. The sensitivity of Ba can be significantly improved. The precision and the lifetime of graphite tube have been improved by adding matrix modifier. The method is simple. The recovery and precision are satisfactory.

Asterriquinones produced by Aspergillus candidus inhibit binding of the Grb-2 adapter to phosphorylated EGF receptor tyrosine kinase

Five new asterriquinone analogs (2-4, 6, 7), together with previously identified neoasterriquinone (1) and isoasterriquinone (5), were isolated from a fermentation broth of the fungus Aspergillus candidus and purified by HSCCC (high speed counter current chromatography) followed by HPLC. The structures were determined by 1D and 2D NMR and MS/MS techniques. All seven showed inhibitory activity against the binding of a recombinant protein containing the SH2 protein domain of Grb-2 to the tyrosine phosphorylated form of the EGF receptor tyrosine kinase. Some of these asterriquinones exhibited specific inhibition of Grb-2 binding compared to Grb-7 and PLC-gamma.

Establishment and cellular characteristics of a hepatocyte cell line (OUMS-31) derived from an acatalasemic mouse

Liver cell lines with very low catalase activity were established from an acatalasemic mouse. Hepatocytes isolated by a collagenase-liver-perfusion technique were cultured in Williams' E medium supplemented with 10% fetal bovine serum. The acatalasemic liver cell line showed approximately 20% of the catalase activity of a normal mouse liver cell line, whereas its glutathione peroxidase activity was approximately equal to that of the normal liver cell line. DNA sequence analysis of this cell line showed the same mutation in the catalase gene as is seen in the acatalasemic mouse. Our observation of intracellular content of hydrogen peroxide (H2O2) radical and increased susceptibility of the cells to H2O2 were compatible with the existence of low catalase activity in the acatalasemic mouse. This hepatocyte cell line should be useful for studying effects of oxidative radical stress at the cellular level.

Transferrin synthesized in cultured human fibroblasts is associated with tubulins and has iron binding capacity

In a previous report (13), using immunocytochemical and fluorescence-labeling techniques, we demonstrated that transferrin is synthesized in cultured human fibroblasts and that it is associated with tubulins in the cells. These morphological findings led us to attempt to elaborate those issues in more detail by biochemical methods. In this report, we were able to prove the association of transferrin produced in cells with tubulins. In addition, the transferrin associated with tubulins was found to bind to iron. These results suggest that endogenous transferrin plays a role in preventing damage caused by free radicals which can be induced by the interaction of iron with the hydrogen peroxide produced in cells.

ATP inhibition of proliferation of immortalized human fibroblasts is greater than that of normal human diploid fibroblasts

It is known that cancers develop by a multi-step process. Normal cells are first immortalized, and then transformed into tumorigenic cells. Normal human cells are very rarely immortalized, but once they are, they are relatively easily transformed into tumorigenic cells. This indicates that the immortalization step plays a critical part in the development of human cancers. Thus, elucidation of the mechanisms of this step would shed light on the process of carcinogenesis in human cells. To understand the causes of immortalization, it is important to determine the differences in cellular phenotype between immortalized and normal human cells. In this study, we found that immortalized human fibroblasts were more sensitive to the growth inhibitory effects of ATP than normal human fibroblasts. ADP was as effective as ATP, but AMP, adenosine, and phosphoric acid were not. These results indicate that a high-energy bound of ATP and ADP may contribute to the growth inhibition of the cells. When the immortalized cells were pulse-labeled with [32P]-ATP, 30-, 31-, 33- and 40-kDa membrane fraction proteins were more prominently labeled in the immortalized cells than in the normal cells. At present, the characteristics of these proteins are being investigated.

Rapid establishment of high-producing cell lines using dicistronic vectors with glutamine synthetase as the selection marker

Recombinant proteins are useful tools in biological research, drug development, and drug screening. Specially designed expression vectors have been developed to introduce cDNA for recombinant protein expression in mammalian cells. We have combined a dicistronic mRNA design for expression of the recombinant protein, using glutamine synthetase (GS) for selection. A soluble form of human interleukin-4 receptor alpha chain was used as the model protein. The dicistronic vectors were compared to a standard expression vector in CHO-K1 cells in parallel experiments. Our data showed that a dicistronic vector containing an internal ribosome entry site (IRES) of the encephalomyocarditis virus (ECMV) was superior to a conventional expression vector in both levels of protein expression and amplification efficiency. The productivity of these clones was stable without selection pressure for an extended period of time. The GS selection system within a dicistronic vector design can achieve rapid and efficient gene amplification for protein production.

[Research on the determination method of trace amount of Pb and Cd in animal bone]

A method for the determination of trace amount of Pb and Cd in animal bone using GFAAS has been established. The samples were determined directly after being diluted by TMAH solution. The method is handy and fast. The recovery is 96.95-103.15%. The RSD is less than 4.81%.

Studies of two-species Bose-Einstein condesation

We describe our recent progress on the investigation of two-species Bose-Einstein condensation. From a theoretical analysis we show that there is a new rich phenomenology associated with two-species Bose-Einstein condensates which does not exist in a single-species condensate. We then describe results of a numerical model of the evaporative cooling process of a trapped two-species gas.

Differential localization of two types of transferrin: produced by human fibroblasts or incorporated from culture medium

In a previous paper, we demonstrated that cultured human fibroblasts synthesize transferrin (Tf). Two types of Tf are present; one is produced by the cells and the other is internalized from the culture medium. To study the metabolism of intracellular Tf, we investigated the subcellular localization of the two types of Tf in human fibroblasts by immunocytochemical and fluorescence-labeling techniques. The internalized Tf was found to be localized in the perinuclear area, and the synthesized Tf was associated with microtubules, forming a fibrous structure in the cytoplasm. When the cells were treated with colchicine which depolymerizes microtubules irreversibly, the synthesized Tf lost its fibrous structure and spread out in cytoplasm, but the internalized Tf remained around the nucleus. These results suggest that the two types of Tf are regulated differently in the cells.

In situ hybridization for gastrin-releasing peptide receptor (GRP receptor) expression in prostatic carcinoma

Bombesin-like peptides (BLPs), which have been implicated in the regulation of growth of prostatic carcinoma cells, are a product of neuroendocrine cells frequently found in prostate tissue and are postulated to play a role in the initiation or progression of prostatic carcinoma. In this report, we examined the expression, in human prostate tissue, of mRNA encoding the 3 known receptors that respond to BLPs in humans, i.e., gastrin-releasing peptide (GRP) receptor, neuromedin B (NMB) receptor and bombesin receptor subtype 3 (BRS-3). Competitive rt-PCR experiments demonstrated the widespread but variable expression of GRP receptor mRNA in fresh-frozen specimens of prostatic carcinoma (12 cases) and benign prostatic hypertrophy (6 cases). NMB receptor mRNA expression was also widespread, but its level was less variable than GRP receptor message. In contrast, we could not detect BRS-3 mRNA in most tissue samples by rt-PCR. To address which cells in the prostate express the GRP receptor, we used in situ hybridization methods to stain selectively GRP receptor mRNA. GRP receptor mRNA was expressed predominantly in the luminal and basal epithelial cells in both histologically normal and cancerous glands within sections of normal (3 cases) and diseased (37 cases) tissue. GRP receptor mRNA staining in cancerous tissue ranged widely from very intense to not detectable (about 30% of the cases), while normal tissue consistently displayed a low level of message staining. Taken together, our results demonstrate expression of the GRP receptor in a high percentage of basal and/or luminal epithelial cells of normal and diseased prostate tissues.

Protein expression both in mammalian cell lines and in yeast Pichia pastoris using a single expression plasmid

We have designed and constructed a novel expression vector capable of producing recombinant proteins in both mammalian cell lines and the yeast strain Pichia pastoris. In this vector, a yeast promoter is placed inside an intron of the mammalian transcription unit. A yeast transcription termination sequence is placed immediately downstream of the mammalian polyadenylation site. In mammalian cells, transcription is driven by a mammalian promoter. The yeast promoter within the intron is removed by RNA processing. However, protein expression in yeast cells can be achieved utilizing the yeast promoter immediately upstream of the 3' splice site and the target genes. Our data indicate that this vector can express beta-galactosidase efficiently in both mammalian cell lines and the yeast strain P. pastoris.