Development of a PCR-based method for monitoring the status of Alcaligenes species in the agricultural environment

To analyze the status of the genus Alcaligenes in the agricultural environment, we developed a PCR method for detection of these species from vegetables and farming soil. The selected PCR primers amplified a 107-bp fragment of the 16S rRNA gene in a specific PCR assay with a detection limit of 1.06 pg of pure culture DNA, corresponding to DNA extracted from approximately 23 cells of Alcaligenes faecalis. Meanwhile, PCR primers generated a detectable amount of the amplicon from 2.2×10(2) CFU/ml cell suspensions from the soil. Analysis of vegetable phylloepiphytic and farming soil microbes showed that bacterial species belonging to the genus Alcaligenes were present in the range from 0.9×10(0) CFU per gram (or cm(2)) (Japanese radish: Raphanus sativus var. longipinnatus) to more than 1.1×10(4) CFU/g (broccoli flowers: Brassica oleracea var. italic), while 2.4×10(2) to 4.4×10(3) CFU/g were detected from all soil samples. These results indicated that Alcaligenes species are present in the phytosphere at levels 10-1000 times lower than those in soil. Our approach may be useful for tracking or quantifying species of the genus Alcaligenes in the agricultural environment.

Effect of molecular orientation angle of imidazolium ring on frictional properties of imidazolium-based ionic liquid

Ionic liquids have significant potential as lubricants, and it is known that ionic liquids exhibit characteristic behavior at solid-liquid interfaces. Although it is believed that the structure of ionic liquids at the interface contributes to the tribological properties in the region of boundary-mixed lubrication, this contribution has not been clarified because such analysis is difficult. In this research, we clarify the lubrication mechanism of an imidazolium-based ionic liquid by comparing the results of friction tests with interfacial molecular orientation analysis using sum frequency generation spectroscopy. Consequently, we clarify that the tilt angle of the imidazolium ring affects the friction coefficient of the ionic liquid; that is, the larger tilt angle, the lower the friction coefficient.

Three-dimensional surface figure measurement of high-accuracy spherical mirror with nanoprofiler using normal vector tracing method

Processing technology using an extreme ultraviolet light source, e.g., next-generation lithography, requires next-generation high-accuracy mirrors. As it will be difficult to attain the degree of precision required by next-generation high-accuracy mirrors such as aspherical mirrors through conventional processing methods, rapid progress in nanomeasurement technologies will be needed to produce such mirrors. Because the measuring methods used for the surface figure measurement of next-generation mirrors will require high precision, we have developed a novel nanoprofiler that can measure the figures of high-accuracy mirrors without the use of a reference surface. Because the accuracy of the proposed method is not limited by the accuracy of a reference surface, the measurement of free-form mirrors is expected to be realized. By using an algorithm to process normal vectors and their coordinate values at the measurement point obtained by a nanoprofiler, our measurement method can reconstruct three-dimensional shapes. First, we measured the surface of a concave spherical mirror with a 1000-mm radius of curvature using the proposed method, and the measurement repeatability is evaluated as 0.6 nm. Sub-nanometer repeatability is realized, and an increase in the repeatability would be expected by improving the dynamic stiffness of the nanoprofiler. The uncertainty of the measurement using the present apparatus is estimated to be approximately 10 nm by numerical simulation. Further, the uncertainty of a Fizeau interferometer is also approximately 10 nm. The results obtained using the proposed method are compared with those obtained using a Fizeau interferometer. The resulting profiles are consistent within the range of each uncertainty over the middle portions of the mirror.

Association between anti-U1 ribonucleoprotein antibodies and inflammatory mediators in cerebrospinal fluid of patients with neuropsychiatric systemic lupus erythematosus

Objective

We investigated possible associations between neurotoxic inflammatory mediators (IMs) and anti-U1RNP antibodies (Abs) in cerebrospinal fluid (CSF) of neuropsychiatric systemic lupus erythematosus (NPSLE).

Methods

Serum and CSF anti-U1RNP Abs were detected using an RNA-immunoprecipitation assay and CSF anti-U1RNP Ab levels were measured by ELISA. IFN-α, MCP-1 and IL-8 levels in CSF were determined by quantitative multiplex cytokine analysis. IM levels were compared among anti-U1RNP-positive and anti-U1RNP-negative NPSLE as well as other rheumatic disease controls (controls).

Results

Anti-U1RNP Abs were detected in serum (58%) and in CSF (18%) of 82 NPSLE patients. CSF MCP-1 levels were higher in NPSLE than in controls. CSF IFN-α level was higher in CSF anti-U1RNP Ab-positive than in -negative patients or controls. When limited to serum anti-U1RNP Ab-positive patients, however, levels of all three IMs in CSF were higher in CSF anti-U1RNP Ab-positive than in -negative patients. Anti-U1RNP Ab levels in CSF correlated with CSF MCP-1, but not IFN-α and IL-8 levels.

Conclusions

CSF anti-U1RNP Ab positivity is associated with increased level of CSF IFN-α. MCP-1 levels correlated with CSF anti-U1RNP Ab levels, whereas the increased CSF MCP-1 was not specific to CSF anti-U1RNP Ab-positive NPSLE.

Electron reemission processes following photoelectron recapture due to post-collision interaction in inner-shell photoionization of water molecules

Electron reemission following photoelectron recapture due to post-collision interaction has been studied at 0.7 eV the inner-shell photoionization threshold of water molecules, using a multi-electron coincidence method. Electron reemissions after single Auger decay occur from O and OH fragments which are produced by the dissociations of high-n Rydberg H2O(+) states populated through photoelectron recapture. In addition, electron reemissions after double Auger decay are identified in triple coincidence events, where autoionization lines from O and O(+) fragments are observed.

Human parvovirus B19 infection mimicking systemic lupus erythematosus

Abstract Although several recent reports have discussed the similarities between human parvovirus B19 (HPV-B19) infection and systemic lupus erythematosus (SLE), the relationship between these conditions has not been established owing to the small number of patients investigated. In 1998-1999, an outbreak of Erythema infectiosum occurred close to our hospital, enabling us to investigate the clinical, hematological, and serological findings, including serum complement and antinuclear antibodies (ANA), in 22 patients with acute HPV-B19 infection. The principal symptoms included rash (86.3%), edema (59%), arthralgia (45.4%) and fever (31.8%). Lymphadenopathy was seen in three of the 22 cases. The laboratory findings showed high incidences of leukopenia (50%), hypocomplementemia (95%), and ANA (64.7%). At the time of disease onset, patients with acute HPV-B19 infection presented with features which were similar to those of SLE. The possibility of HPV-B19 infection should therefore be considered in patients presenting with SLE-like features.

Mechanosensitive channels are activated by stress in the actin stress fibres, and could be involved in gravity sensing in plants

Mechanosensitive (MS) channels are expressed in a variety of cells. The molecular and biophysical mechanism involved in the regulation of MS channel activities is a central interest in basic biology. MS channels are thought to play crucial roles in gravity sensing in plant cells. To date, two mechanisms have been proposed for MS channel activation. One is that tension development in the lipid bilayer directly activates MS channels. The second mechanism proposes that the cytoskeleton is involved in the channel activation, because MS channel activities are modulated by pharmacological treatments that affect the cytoskeleton. We tested whether tension in the cytoskeleton activates MS channels. Mammalian endothelial cells were microinjected with phalloidin-conjugated beads, which bound to stress fibres, and a traction force to the actin cytoskeleton was applied by dragging the beads with optical tweezers. MS channels were activated when the force was applied, demonstrating that a sub-pN force to the actin filaments activates a single MS channel. Plants may use a similar molecular mechanism in gravity sensing, since the cytoplasmic Ca(2+) concentration increase induced by changes in the gravity vector was attenuated by potential MS channel inhibitors, and by actin-disrupting drugs. These results support the idea that the tension increase in actin filaments by gravity-dependent sedimentation of amyloplasts activates MS Ca(2+) -permeable channels, which can be the molecular mechanism of a Ca(2+) concentration increase through gravistimulation. We review recent progress in the study of tension sensing by actin filaments and MS channels using advanced biophysical methods, and discuss their possible roles in gravisensing.

New candidates for mechano-sensitive channels potentially involved in gravity sensing in Arabidopsis thaliana

The mechano-sensitive channels of plants may sense increases in tension induced by mechanical stimuli, such as touch, wind and turgor pressure, and a gravitational stimulus. Recent studies have identified plant homologues of the bacterial mechano-sensitive channel MscS, which is gated by membrane tension and reduces intracellular osmolality by releasing small osmolytes from bacterial cells. However, the physiological roles of these homologues have not yet been clearly elucidated, and only two of them have been shown to be involved in the protection of osmotically stressed plastids in Arabidopsis thaliana. We identified another group of candidates for mechano-sensitive channels in Arabidopsis, named MCA1 and MCA2, whose homologues are exclusively found in plant genomes. MCA1 and MCA2 are composed of 421 and 416 amino acid residues, respectively, share 73% homology in their amino acid sequences, and are not homologous to any known ion channels or transporters. Our structural study revealed that the N-terminal region (one to 173 amino acids) of both proteins was necessary and sufficient for Ca(2+) influx activity. Interestingly, this region had one putative transmembrane segment containing an Asp residue whose substitution mutation abolished this activity. Our physiological study suggested that MCA1 expressed at the root tip was required for sensing the hardness of the agar medium or soil. In addition, MCA1 and MCA2 were shown to be responsible for hypo-osmotic shock-induced increases in [Ca(2+) ]cyt . Thus, both proteins appear to be involved in the process of sensing mechanical stresses. We discussed the possible role of both proteins in sensing mechanical and gravitational stimuli.

Abstract P6-05-14: Prognostic significance of Ki-67 index value at primary breast tumor in recurrent breast cancer

Introduction: The Ki-67 index value is a prognostic factor in primary breast cancer and is a proliferation marker that also distinguishes between luminal type A and type B breast cancer. Moreover, change in Ki-67 index value due to treatment and recurrence is considered to be important in treating breast cancer. The evaluative procedure in this study was on two levels; first, we examined whether the baseline Ki-67 value at the primary tumor is useful as a prognostic factor after recurrence, and second, we looked at the changes in the values after recurrence.

Patients and Methods: Immunohistochemical (IHC) analysis of the Ki-67 index was performed on 4701 patients with primary breast cancer from 1987 until March 2013 at Kumamoto City Hospital. Out of these patients, there were 666 consecutive cases with recurrence after primary surgery. The fraction of proliferating cells (positive for Ki-67) was based on a count of at least 500 tumor cells in the area including the hot spot, and the Ki-67 values were divided into 2 or 3 groups; <20% and ≥20% (and ≥50%). Items examined were ER, PgR, HER2, tumor size, nodal status at primary tumor, and recurrent site (soft tissue, bone and viscera) and disease-free interval (DFI). Cox's proportional hazard model was used to perform a univariate and multivariate analyses of the factors related to overall survival (OS) after recurrence. The median follow-up period was 65.9 months in the remaining survival group. In 101 recurrent cases from whom the recurrent lesion was resected, the change in biological markers (Ki-67, ER and PgR) were evaluated.

Results: The median Ki-67 value at baseline was 20% in all the cases and 27% in the recurrent cases. In terms of recurrent site, the values were low (23%) in patients with bone metastasis, whereas patients with liver or brain metastasis showed higher values (38% and 53%, respectively). Moreover, DFI was inversely correlated with Ki-67 values. Univariate and multivariate analyses were performed to identify the prognostic factors for OS after recurrence. The significant factors included tumor size, lymph node status, ER, PgR, DFI, recurrent site, and the Ki-67 index value. Among these factors, a multivariate analysis revealed that the Ki-67 index value at primary tumor was an independent significant factor. The hormone receptor positive rate from the primary tumor to recurrence decreased from 67.3% to 63.4% and 64.4% to 50% for ER and PgR, respectively. The Ki-67 index value increased significantly from a mean of 28.9% at primary tumor to 35.7% at relapse. Furthermore, the Ki-67 index value at primary tumor was a significant prognostic factor for OS after recurrence in this cohort.

Conclusion: The Ki-67 value at primary tumor was a significant prognostic factor for OS after recurrence. The Ki-67 index value increased significantly after recurrence. It is therefore important to take the Ki-67 index into consideration in the treatment and follow-up of breast cancer patients.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-05-14.

Abstract P5-05-06: Menopausal status: An important consideration in determining the biology and prognosis of estrogen receptor-positive and progesterone receptor-negative breast cancer

Background: Transcription of the progesterone receptor (PgR) gene is regulated by estrogen in the breast tissue. PgR loss is considered to be a result in the reduction of estrogen receptor (ER) activity, due to either low circulating estrogen in some older women or a high growth factor signaling. Among the ER-positive breast cancer patients, PR-negative cases frequently have a higher resistance to endocrine therapy, and have a poorer prognosis. Therefore, we examined the clinical significance of ER+/PgR- tumors in luminal/HER2 negative breast cancer and its relationship to menopausal status.

Methods: The sample for this study came from 1791 consecutive patients with HER2 negative primary breast cancer from January 2002 to March 2013. The ER and PgR expressions were evaluated using immunohistochemistry (IHC). 1586cases had ER+/PgR+ tumor, 205cases had ER+/PgR- tumor. The items examined were nuclear grade, Ki-67 index value, TP53, tumor size and number of lymph node involvement. The Ki-67 index value and TP53 were evaluated using IHC and the cut-off values were 20% and 50%, respectively. Recurrence free survival (RFS) and breast cancer-specific survival (BCSS) was calculated using the Kaplan-Meier method and evaluated by the log-rank test or generalized Wicoxon test in stage 1 and 2 breast cancer.

Results: In terms of the distribution of ER and PgR status, ER+/PgR- were frequently seen in postmenopausal patients (13.7% vs 6.8%, respectively). Patients with ER+/PgR-and HER2 negative tumors had significantly smaller tumors, lower Ki-67 values, and a lower nuclear grade in the postmenopausal group compared with those in the premenopausal group. Moreover, RFS trended to be better in the postmenopausal group (p = 0.06), but there was no significant difference. BCSS was significantly higher in the postmenopausal cases (p = 0.001). On the other hand, in patients with ER+/PgR+ tumors, there was no significant difference in RFS and BCSS between the post- and pre-menopausal groups.

Conclusion: The ER+/PgR- tumors were more commonly seen in postmenopausal patients. The biological characteristics of ER+/PgR- tumors were significantly different in terms of the Ki-67 index value, nuclear grade, and the prognosis (BCSS and RFS) between pre- and postmenopausal status. Moreover, the postmenopausal group had a more favorable biology and prognosis than the premenopausal group. Therefore, the findings in this study indicate that menopausal status is related to the biology and prognosis in patients with ER+/PgR- tumors.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-05-06.

Abstract P1-02-01: Pre-analytical setting is critical for an assessment of the Ki-67 labeling index for breast cancer

Background: The Ki-67 labeling index (LI) is useful in determining the efficacy of chemotherapy for patients with ER-positive and HER2-negative breast cancer. However, standardization of Ki-67 assessment has not yet been established. In terms of the factors that may affect Ki-67 LI, recent studies have focused on inter-observer variability in the interpretation of these values and insufficient attention has been given to the importance of handling the tissue. Therefore, this study focused on the effect of tissue fixation on Ki-67 LI.

Methods:

The effects of several pre-analytical conditions on the Ki-67 LI were studied as follows;

(1) Type of fixation: Each 173 surgically excised tumors were fixed with either 10% neutral buffered formalin or 15% formalin on the same condition, followed by assessment of Ki-67 LI.

(2) Time of fixation: Each study was repeated more than three times to confirm the result.

A: Time to fixation: A part of tumor, sliced from the surgically excised tumor, was kept in 4° for several hours to overnight before formalin fixation. Ki-67 LI was compared between the tumor with immediate and delayed fixation.

B: Time of fixation:

Insufficient fixation: A part of tumor, sliced from the surgically excised tumor, was fixed with formalin for 3 hours, followed by preparation of a paraffin-embedded block. Ki-67 LI was compared between the tumor with proper and shorter fixation.

Prolonged fixation: Some pieces of slice were prepared from the surgically excised tumor, followed by each preparation of a paraffin-embedded block at a designated fixation period. Ki-67 LI was compared among each sample fixed in a different period of time.

(3) Surgically excised tumors on Ki-67 LI:

A: Effect of cutting onto the tumor before fixation: Ki-67 LI in each 595 surgically excised tumor with or without cutting onto the tumor before fixation, was analyzed.

B: Comparison between core needle biopsy and surgically excised tissue: Ki-67 LI in each 136 pairs of core needle biopsy and surgically excised tissue originated from the same tumor was compared.

Results:

(1) Ki-67 LI was significantly higher when 10% neutral buffered formalin was used as a fixative compared to 15% formalin (p = 0.018).

(2) Ki-67 LI was reduced in some degree when time to fixation was delayed, while insufficient fixation caused dramatic reduction of Ki-67 LI compared to that seen in an either ER or HER2. A prolonged period of fixation caused gradual reduction of Ki-67 LI associated with diminished nuclear labeling.

(3) Ki-67 LI was significantly higher in the tumor cut onto before fixation (p = 0.018). There was no significant difference in Ki-67 LI between core needle and surgically excised specimens (p = 0.107), when the tumor was properly fixed.

Conclusion: Our results suggest that pre-analytical setting critically influences the Ki-67 labeling. In order to standardize Ki-67 LI assessment in breast cancer, the care in handling of the pre-analytical tissue is crucial in determining accurate Ki-67 values.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-02-01.