Centripetal Propagation of Vasoconstriction at the Time of Headache Resolution in Patients with Reversible Cerebral Vasoconstriction Syndrome

BACKGROUND AND PURPOSE

Reversible cerebral vasoconstriction syndrome is characterized by thunderclap headache and diffuse segmental vasoconstriction that resolves spontaneously within 3 months. Previous reports have proposed that vasoconstriction first involves small distal arteries and then progresses toward major vessels at the time of thunderclap headache remission. The purpose of this study was to confirm centripetal propagation of vasoconstriction on MRA at the time of thunderclap headache remission compared with MRA at the time of reversible cerebral vasoconstriction syndrome onset.

MATERIALS AND METHODS

Of the 39 patients diagnosed with reversible cerebral vasoconstriction syndrome at our hospital during the study period, participants comprised the 16 patients who underwent MR imaging, including MRA, within 72 hours of reversible cerebral vasoconstriction syndrome onset (initial MRA) and within 48 hours of thunderclap headache remission.

RESULTS

In 14 of the 16 patients (87.5%), centripetal propagation of vasoconstriction occurred from the initial MRA to remission of thunderclap headache, with typical segmental vasoconstriction of major vessels. These mainly involved the M1 portion of the MCA (10 cases), P1 portion of the posterior cerebral artery (10 cases), and A1 portion of the anterior cerebral artery (5 cases).

CONCLUSIONS

This study found evidence of centripetal propagation of vasoconstriction on MRA obtained at the time of thunderclap headache remission, compared with MRA obtained at the time of reversible cerebral vasoconstriction syndrome onset. If clinicians remain unsure of the diagnosis during early-stage reversible cerebral vasoconstriction syndrome, this time point represents the best opportunity to diagnose reversible cerebral vasoconstriction syndrome with confidence.

Abstract P1-15-03: Prevention of letrozole–induced bone loss using risedronate in postmenopausal women with hormone receptor positive breast cancer: A multicenter randomized clinical trial

Background

Prevention of letrozole–induced bone loss using oral risedronate has not been proved in the Japanese women. The aim of this study was to assess the effect of risedronate 17.5mg/week on bone mineral density (BMD) in postmenopausal, early breast cancer patients scheduled to receive adjuvant letrozole.

Patients and Methods

Postmenopausal women with hormone receptor–positive early breast cancer were assigned to one of two strata according to their baseline BMD T-score as being at low and high risk of osteoporosis. Patients with low risk (-2.5 ≤ T score) were randomly assigned to letrozole and risedronate (L+R) or to letrozole alone (L). Patients with high risk (-2.5 > T score) received letrozole and risedronate (L+R). Letrozole was given at a dosage of 2.5 mg/day while oral risedronate was given at 17.5mg/week. The primary end point was the change in lumbar spine (LS) BMD at 12 months. The secondary end points included change in total hip (HP) BMD and bone turnover markers.

Results

In the low risk group (N=103), treatment with L+R resulted in a significant increase in BMD at LS and at HP compared to treatment with L only at 12 months (1.8% vs -2.2%, P < 0.001, and -0.3% vs -2.9%, P = 0.001, respectively). In the L+R group, significant decreases in bone turnover makers, NTX and PINP, were recognized compared with L only at 12months (-11.1% vs. 27.5%, P<0.001, -42.3% vs. 15.2%, P<0.001, respectively). In the high risk group (N=28), treatment with L+R resulted in a significant increase in BMD at LS and prevention of decrease in BMD at HP (3.6%; 95%CI, 1.8% to 5.3%, p=0.003, 0.3%; 95%CI, -1.3% to 1.8%, p=0.47, respectively).

Estimated Percentage Change From Baseline to 6 and 12 Months in Lumbar Spine and Total Hip BMD   From Baseline to 6 MonthsFrom Baseline to 12 MonthsBMD areaRisk GroupTreatmentChange in BMD (%), 95% CIPChange in BMD (%), 95% CIPLumbar spineLow riskL+R1.7 (-1.3 to 4.7)<0.0011.8 (-2.1 to 5.7)<0.001  L-1.6 (-4.3 to 1.1) -2.2 (-5.7 to 1.3)  High riskL+R1.8 (0.4 to 3.2)0.043.6 (1.8 to 5.3)0.003Total hipLow riskL+R-0.2 (-2.7 to 2.3)0.001-0.3 (-3.2 to 2.6)0.001  L-2.2 (-5.4 to 1.0) -2.9 (-7.2 to 1.4)  High riskL+R0.1 (-1.3 to 1.6)0.610.3 (-1.3 to 1.8)0.47BMD: bone mineral density, L: Letrozole, R: risedronate

Four patients (14.3%) improved from osteoporotic region to the osteopenic region with L+R treatment. Letrozole and risedronate were well tolerable and there was no serious adeverse event including osteonecrosis of jaw.

Conclusions

At 12 months, 17.5mg/week risedronate therapy prevented bone loss in postmenopausal women with breast cancer who were receiving adjuvant letrozole, of which results were compatible with previous findings of western populations.

Citation Format: Kadoya T, Masumoto N, Shigematsu H, Emi A, Kajitani K, Kobayashi Y, Funakoshi M, Kawabuchi Y, Ohara M, Matsuura K, Noma M, Sasada T, Okada M. Prevention of letrozole–induced bone loss using risedronate in postmenopausal women with hormone receptor positive breast cancer: A multicenter randomized clinical trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-15-03.

Abstract P4-09-17: Wnt5a expression is associated with high-grade malignancy in ER-positive breast cancer

Background: Wnt5a is a representative ligand that activates the β-catenin-independent pathways. The purpose of our study is to elucidate the implication of Wnt5a expression in breast cancer.

Materials and methods: One hundred seventy eight breast cancer patients (mean age ± SD: 59.6 ± 13.2 years) with clinical Stage I∼III between January 2011 and February 2014, were prospectively evaluated. Patients who underwent operation without neoadjuvant therapy were enrolled to this study. The immunohistochemical analyses of Wnt5a protein was performed to evaluate relationships between Wnt5a expression and clinicopathological factors. MCF7 cells that stably express Wnt5a were generated and used for cDNA microarray analyses to investigate Wnt5a-dependent gene expression.

Results: Wnt5a expression was significantly more frequent when estrogen receptor (ER) was present, 68/153 (44%) than when ER was absent, 1/25 (4%) (p<0.001). Wnt5a expression was also related with progesterone receptor (PgR) (P<0.001), but not with HER2 status (P=0.496). In ER-positive breast cancer, a significant interaction between expression of Wnt5a with lymph node metastasis (P<0.001), nuclear grade (P=0.004), lymphatic invasion (P=0.002), vessel invasion (P=0.050), and pStage (P<0.001). Microarray analyses identified several genes induced by Wnt5a (>3.0 fold), involving activated leukocyte cell adhesion molecule (ALCAM). ALCAM is known to be related with apoptosis, invasion and prognosis of breast cancer. Wnt5a expression levels correlated with those of ALCAM in ER-positive tumor samples from patients by immunohistochemical analyses (P<0.001).

Relationship between Wnt5a expression and clinicopathological featureClinicopathological featuretotalWnt5a expressionP value (n=153)Negative (n=85)Positive (n=68) Age (median, range) 63, 35-8657.5, 34-870.065Age, n (%)    ≤4528 (18)13 (46)15 (54) >45125 (82)72 (58)53 (42)0.282Menopausal status, n (%)    Premenopausal58 (38)27 (47)31 (53) Postmenopausal95 (62)58 (61)37 (39)0.080Tumor size, n (%)    pT1 ≤20mm104 (44)63 (61)41 (39) pT2/pT3 >20mm49 (56)22 (45)27 (55)0.069lymph node metastasis, n (%)    Negative103 (67)72 (70)31 (30) Positive50 (33)13 (26)37 (74)<0.001Nuclear grade, n (%)    1/285 (56)56 (66)29 (34) 368 (44)29 (43)39 (57)0.004Lymphatic invasion, n (%)    Negative101 (66)65 (64)36 (36) Positive52 (34)20 (38)32 (62)0.002Vessel invasion, n (%)    Negative142 (93)82 (58)60 (42) Positive11 (7)3 (27)8 (73)0.050Ki-67, n (%)    0-2067 (44)43 (64)24 (36) 21-10086 (56)42 (49)44 (51)0.058pStage, n (%)    pStage I80 (52)58 (73)22 (28) pStage II64 (42)27 (42)37 (58) pStage III9 (6)0 (0)9 (100)<0.001ALCAM, n (%)    Negative85 (56)64 (75)21 (25) Positive68 (44)21 (31)47 (69)<0.001

Conclusions: Wnt5a express in ER-positive breast cancer and are associated with high-grade malignancy. Wnt5a could be a prognostic factor of ER-positive breast cancer. These results have implications that Wnt5a may become a preoperative and postoperative assessment tool for tumor malignancy grade and a potential therapeutic target except endocrine therapy in ER-positive breast cancer. In future studies, further research on Wnt5a are required to develop a novel treatment for more improved outcomes in a great variety of breast cancer.

Citation Format: Kobayashi Y, Kadoya T, Gouda N, Kajitani K, Emi A, Shigematsu H, Masumoto N, Okada M. Wnt5a expression is associated with high-grade malignancy in ER-positive breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-09-17.

Acute Phosphate Nephropathy with Diffuse Tubular Injury Despite Limited Calcium Phosphate Deposition

An 86-year-old woman developed acute kidney injury after colonoscopy. A renal biopsy showed diffuse tubular injury with minimal calcium phosphate deposits (CPDs), which were thought to be caused by an oral sodium phosphate bowel purgative before colonoscopy. According to these findings, she was diagnosed with acute phosphate nephropathy (APhN). In contrast to previous reports of diffuse tubular injury associated with tubular CPDs in APhN, this case demonstrated diffuse tubular injury despite a limited distribution of CPDs, suggesting that calcium phosphate can cause tubular injury without deposition. This case thus supports the hypothesis that urinary calcium phosphate crystals may cause tubular injury via other mechanisms, including inflammatory cytokines.

Neuroradiologic Diagnosis of Minor Leak prior to Major SAH: Diagnosis by T1-FLAIR Mismatch

BACKGROUND AND PURPOSE

In major SAH, the only method to diagnose a preceding minor leak is to ascertain the presence of a warning headache by interview; however, poor clinical condition and recall bias can cause inaccuracy. We devised a neuroradiologic method to diagnose previous minor leak in patients with SAH and attempted to determine whether warning (sentinel) headaches were associated with minor leaks before major SAH.

MATERIALS AND METHODS

We retrospectively evaluated 127 patients who were admitted with SAH within 48 hours of ictus. Previous minor leak before major SAH was defined as T1WI-detected clearly bright hyperintense subarachnoid blood accompanied by SAH blood on FLAIR images that was distributed over a larger area than bright hyperintense subarachnoid blood on T1WI (T1-FLAIR mismatch).

RESULTS

The incidence of warning headache before SAH was 11.0% (14 of 127 patients, determined by interview). The incidence of T1-FLAIR mismatch (neuroradiologic diagnosis of minor leak before major SAH) was 33.9% (43 of 127 patients). Of the 14 patients with warning headache, 13 had a minor leak diagnosed by T1-FLAIR mismatch at the time of admission. Variables identified by multivariate analysis as significantly associated with minor leak diagnosed by T1-FLAIR mismatch included 80 years of age or older, rebleeding after admission, intracerebral hemorrhage on CT, and mRS scores of 3-6.

CONCLUSIONS

We conclude that warning headaches diagnosed by interview are not a product of recall bias but are the result of actual leaks from aneurysms.

Cell sheet injection as a technique of osteogenic supply

We previously reported a new cell transplantation method utilizing injections of mesenchymal stem cell (MSC) sheets that have osteogenic potential. After subcutaneous transplantation without any scaffold, the sheet demonstrated in vivo bone formation. In the present study, we transplanted such sheets by injection into implanted ceramics and assessed whether the injectable MSC sheets could stimulate osteogenic integration of the ceramics. To fabricate MSC sheets, bone marrow cells cultured from femur shafts of 7-week-old rats were subcultured in regular 10-cm dishes containing dexamethasone and ascorbic acid phosphate until confluent. Each cell sheet was then lifted using a scraper. Porous β-tricalcium phosphate (β-TCP) disks (5 mm Φ×2 mm) were transplanted subcutaneously into the backs of the rats. Immediately following implantation, the sheets were injected around the disks via a 16G needle (immediate group). Cell sheets were also injected into the remaining implanted disks 1 week after disk implantation (1-wk group). Four weeks following sheet injection, radiography and histology revealed calcification and bone tissue around the harvested disks of the immediate group (eight disks exhibited bone formation/eight implanted disks), whereas calcification and bone tissue were observed in 50% of the samples in the 1-wk group (four disks exhibited bone formation/eight implanted disks). The present study indicates that injected cell sheets can supply osteogenic potential to implanted ceramics. Owing to the usage of a needle for cell sheet transplantation, such an injection method can be applied as a minimally invasive technique of osteogenic supply to implanted ceramics.

A case of podocytic infolding glomerulopathy with multiple myeloma

BACKGROUND

Podocytic infolding glomerulopathy (PIG) is a recently described condition causing rare pathological changes to the glomeruli, and has attracted considerable attention. PIG is characterized by specific changes to the thickened glomerular basement membrane (GBM), including microspheres, microtubular structures, and podocytic infolding. Only a small number of cases of PIG have been reported. The clinical features and pathogenesis of this condition are still unclear. To elucidate the characteristics of this glomerulopathy, it is necessary to accumulate information from reported cases. We present here the first reported case of PIG with multiple myeloma.

CASE PRESENTATION

A 79-year-old Japanese man was admitted to his local hospital with proteinuria, hypergammaglobulinemia, hypoalbuminemia, and kidney dysfunction. Laboratory tests revealed monoclonal IgG(λ) M proteins in the serum and Bence-Jones proteins in the urine. Bone marrow aspiration showed monoclonal plasma cell proliferation, indicating a diagnosis of multiple myeloma. Renal biopsy was performed to determine the cause of the proteinuria and kidney dysfunction. Histological examination of the biopsy specimen showed glomeruli with an irregularly thickened GBM and bubble-like structures in the capillary walls. Immunofluorescence staining did not show glomerular deposition of immunoglobulins, light chains, or complement components. Congo red staining did not show amyloid deposition. Electron microscopy showed an irregularly thickened GBM with unusual structures in the glomerular capillary walls including podocytic infolding and microspheres, suggesting PIG. There were no electron-dense deposits in the GBM, while various findings indicating podocyte injury were detected.

CONCLUSION

We present here the first reported case of PIG in a patient with multiple myeloma. The mechanisms underlying the development of PIG in multiple myeloma are unknown, but may be associated with podocyte injury.

Abstract P2-03-07: Prediction of the pathological response to neoadjuvant chemotherapy in patients with breast cancer using sonazoid-enhanced ultrasonography

Background:

Altered blood flow in malignant tumors is evidenced by contrast-enhanced ultrasonography (CEUS) because of its image perfusion capabilities.

This study aimed to investigate the value of CEUS in the evaluation of the response of breast cancer lesions to neoadjuvant chemotherapy (NAC). We evaluated whether the prediction of a pathological complete response (pCR) using CEUS was more precise than that using other standard evaluation methods such as magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT).

Methods:

Ten patients (mean age, 50.2 years) who underwent NAC for invasive breast cancer between September 2012 and April 2013 were eligible for this cohort study. Clinical tumor response was evaluated using contrast-enhanced MRI, PET/CT, and CEUS following NAC. A pCR was defined as the absence of invasive cancer in the breast and lymph nodes according to the Japanese Breast Cancer Society criteria.

A clinically complete response (cCR) was defined as the absence of residual disease on MRI and PET/CT. The HI VISION ASCENDUS (Hitachi Aloka Medical Corp.) was used for ultrasonography. Tumors were observed 50 s after Sonazoid injection at a dose of 0.01 ml/kg. A time-intensity curve of tumor signal intensity was drawn. The brightness of the tumor was digitized and the curve was created on the basis of brightness changes over time. The intensity of brightness of the breast cancer lesions was calculated as the increased rate of brightness (IRB) using the following formula: maximal intensity/intensity before contrast.

Results:

Four (40%) of the 10 patients were diagnosed with pCR by NAC. Among 4 (40%) patients diagnosed with cCR by MRI, 1 (25%) achieved pCR. All patients were diagnosed with pCR by PET/CT. The IRB values of the 10 patients who received CEUS before surgery were 1.0, 1.1, 1.2, 1.2, 1.3, 1.6, 1.8, 1.9, 2.5, and 4.2. The IRB values of the 4 patients diagnosed with pCR were 1.0, 1.1, 1.2, and 1.2. IRB values were significantly lower in patients who achieved pCR than in those who did not (pCR vs. no pCR, 1.1 ± 0.9 vs. 2.2 ± 1.0, P < 0.05). Furthermore, among the patients who achieved pCR, the IRB values of 2 patients with no residual ductal carcinoma in situ (DCIS) were 1.0 and 1.1, whereas those of 2 patients with residual DCIS were both 1.2.

In the 4 patients who achieved cCR as diagnosed by MRI and PET/CT, 3 with pathological residual disease had detectable IRB by CEUS.

table 1caseageStageSub typeMRIPET-CTpathological responseIncrease rate of brightness (IRB)167T2N1 IIBLuminal HER2PRCRCR1237T2N0 IIAHER2 positivePRCRCR1.1346T3N1 IIIAHER2 positiveCRCRCR1.2446T2N3c IIICLuminal HER2PRCRCR1.2564T2N0 IIAHER-2 positiveCRCRPR1.3658T2N1 IIBLuminal BCRCRPR1.6738T2N0 IIALuminal BPRCRPR1.8857T1cN0 ILuminal HER-2PRCRPR1.9939T2N1 IIBLuminalBSDCRSD2.51050T2N1 IIBTriple negativePRCRSD4.2

Conclusions:

The prediction of pCR after NAC in patients with breast cancer is more precise with Sonazoid-enhanced ultrasonography than with standard methods such as MRI and PET/CT. Furthermore, CEUS may be useful for predicting residual DCIS on the basis of brightness intensity.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-03-07.

Noise models and cryo-EM drift correction with a direct-electron camera

Blurring due to specimen-holder drift is a common occurrence in cryo-EM images. Cameras employing active-pixel sensors are capable of high frame rates such that a single low-dose exposure can be acquired as a series of frames. In this paper we consider the possibility of tracking and compensating for overall drift in typical single-particle specimens through the analysis of frame sequences. A problem that arises in tracking through cross-correlation of frames obtained with the DE-12 camera from Direct Electron LLC is the presence of "hot-pixel noise". This random pattern of bright pixels is highly correlated among frames. We show how a model of this noise can be employed to greatly reduce its effects. A filter function is derived that optimizes the tracking of image shifts by cross-correlation, and we demonstrate the tracking of specimen drift in typical cryo-EM specimens.

Abstract P6-07-26: Prognostic significance of the maximal value of the baseline standardized uptake value on fluorine 18 fluorodeoxyglucose positron emission tomography/computed tomography for predicting pathologic malignancy of operable breast cancer with neoadjuvant chemotherapy

PURPOSE: [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is potentially useful in predicting pathological complete response (pCR), disease free survival (DFS) and overall survival (OS) of breast cancer patients with neoadjuvant chemotherapy.

MATERIALS AND METHODS: 77 breast cancer patients (mean age ± SD: 52.6 ± 11.2 years) with clinical Stage I∼III between January 2006 and December 2011, were prospectively evaluated (median follow up period:26.5 months). Neoadjuvant chemotherapy of an anthracycline-based regimen and taxane was performed, and patients underwent a whole-body FDG PET/CT before and after chemotherapy. The maximal value of the baseline standardized uptake values (SUVmax) were assessed for predicting pCR, DFS and OS. For the evaluation of relationship between SUVmax values and prognosticators such as hormone receptors, human epidermal growth factor receptor 2 (HER2), nuclear grade, lymph node metastasis and tumor size, statistical analyses were performed using Student t test and log-rank test, and p values of less than 0.05 were considered to indicate statistically significant differences.

RESULTS: Clinical Stage included were I (n = 2, 2.6%), II (n = 62, 80.5%) and III (n = 12, 15.6%). Tumors with estrogen receptor positive were 52 (67.5%) and negative were 24 (31.2%). Therapeutic response by neoadjuvant chemotherapy was obtained in 15 patients (19.5%) with pCR and 60 (77.9%) without pCR. Patients were divided into two groups according to cut-off SUVmax established on the basis of receiver operating characteristic (ROC) analysis (<6.0 vs. ≥6.0, AUC=0.721). When related to the biologic parameters, estrogen receptor (OR:3.75, 95%Cl:1.36–10.35, p = 0.02), but not progesterone receptor (OR:2.31, 95%Cl:0.89–6.00, p = 0.08) nor HER2 status (OR:1.51, 95%Cl:0.47–4.85, p = 0.70) were found strong relation to SUVmax values.

Growth rates of abdominal aortic aneurysms in Japanese patients observed in one institute

AIM

The aim of this paper was to investigate the growth rate of abdominal aortic aneurysms (AAA) in Japanese patients.

METHODS

We retrospectively studied patients conservatively followed with infrarenal AAA in terms of AAA diameter measured using computed tomography (CT) in our hospital between 1999 and 2009. The AAA surgery criterion in our institute was a diameter ≥ 5.0 cm or a growth rate ≥5 mm/year. We estimated operation-free ratios by initial AAA diameter and changes in AAA growth rates. Patients with an initial AAA diameter < 5.0 cm were divided into 2 groups. Patients with AAA that met the criteria for surgery were classified into the expansion group, and those remaining into the non-expansion group. Their AAA growth rates were compared.

RESULTS

The group consisted of 124 patients (average age, 73.7±8.6 years (range 54-92)) who had at least 2 recorded AAA measurements. The average follow-up period was 3.0±2.2 years (range 0.3-10.2). There were no cases of rupture during follow-up. Twenty-six patients (21.0%) underwent surgery (open replacement [N.=20]; endovascular abdominal aneurysm repair [N.=6]). The growth rate determined from the initially measured diameter was significantly faster in AAAs measuring 5.0-5.4 cm than in AAAs measuring 4.5-4.9 cm (P=0.01). More than 90% of patients with an initial AAA diameter <5.0 cm were observed conservatively for 2 years or more. However, more than half of the patients with an initial AAA diameter ≥4.0 cm needed surgery within 5 years. The growth rates of AAAs for each size during growth were significantly faster when the AAA diameter was 4.5-4.9 cm than when it was 4.0-4.4 cm (P=0.006), and when the AAA diameter was 5.0-5.4 cm than when it was 4.5-4.9 cm (P = 0.009). The expansion and non-expansion groups consisted of 38 (34.2%) and 73 (75.8%) patients, respectively. The AAA growth rate in the expansion group was significantly faster than that in the non-expansion group (3.4±2.2 mm/year vs. 1.4±1.3 mm/year, P=0.0001).

CONCLUSION

It may be considered that the appropriate indication for AAA repair is defined by a diameter of 5.0 cm for Japanese patients. Patients with AAA that is growing continuously by ≥3 mm/year and who have low operative risk may undergo surgery even if their AAA is <5.0 cm.

P3-07-27: ROCK II Expression Can Be a Potential Marker of Non-Sentinel Lymph Node Metastasis in Breast Cancer Patients with Sentinel Lymph Node Involvement

(Background) It becomes controversy whether axillary lymph node dissection is mandatory performed for breast cancer patients with positive sentinel lymph nodes (SNs), given that more than half of patients with a positive sentinel lymph biopsy have no metastasis in non-sentinel lymph nodes (non-SNs). Rho-associated kinase (ROCK) is essential part in tumor invasion and metastasis, and its activation is reported to be potential marker of lymph node metastasis.

(Purpose) The purpose of this study was to evaluate the expression of ROCK II as predictive factor of non-SNs metastasis in breast cancer patients with positive SNs.

(Patients and Method) ROCK II protein expression was determined using immunohistochemical analysis on formalin-fixed and paraffin-embedded primary tumor samples composed of 119 SN-positive patients who underwent axillary lymph node dissection in National Kyushu Cancer Center. ROCK II expression was defined positive when there was strong intensity of cytoplasm staining.

(Results) ROCK II expression tended to be strong in invasive area, but weak in intraductal component. Of the 119 patients, 35 (29%) were determined to be positive for ROCK II expression. Patients with ROCK II positive tumor had significantly higher probability of non-SNs metastasis compared with patients with ROCK II negative tumor (20/35, 57% for positive; 28/84, 33% for negative, p=0.02). In multivariate analysis, positive ROCK II expression was significantly associated with non-SNs metastasis even after accounting for other predictive factors including tumor size, lymphovascular invasion, number of SNs metastasis and extra-capsule invasion (positive vs. negative, HR 2.6, p=0.04).

[Thoracoscopic surgery for intractable pneumothorax under epidural and local aesthesia]

Thoracoscopic surgery under epidural and local anesthesia for intractable pneumothorax were performed in 26 patients. A total of 29 thoracoscopic operation were performed in 26 patients. Twenty-three patients undervent only a single thoracoscopic operation, and 3 patients underwent twice thoracoscopic operations. We could control the air leak of intractable pneumothorax with the covering of polyglycolic acid sheets using aerosolized fibrin glue in 25 patients. In all patients postoperative course was uneventful and there was no operative death.

Transfection of human HGF plasmid DNA improves limb salvage in Buerger's disease patients with critical limb ischemia

AIM

Hepatocyte growth factor is a potent angiogenic agent. This study investigated the efficacy and safety of intramuscular injection of naked plasmid DNA encoding the human hepatocyte growth factor gene in Japanese patients with Buerger's disease and critical limb ischemia.

METHODS

An open-label clinical study was performed at eight hospitals in Japan from May 2004 to April 2008. Ten patients were enrolled. They had Buerger's disease with ischemic ulcers, were not candidates for revascularization, and were unresponsive to conventional drug therapy. Treatment consisted of 8 injections (total dose: 4 mg) of hepatocyte growth factor plasmid, which were administered into the calf muscles and/or distal thigh muscles of the ischemic limbs under ultrasound guidance. Administration was done twice at an interval of 4 weeks. If there was no improvement after 2 doses, a 3rd dose could be administered. The response to treatment was evaluated from the reduction of ischemic ulcer size.

RESULTS

The size of ischemic ulcers showed a decrease in 6/9 (66.7%) patients and the ulcers healed completely in 5/9 (55.6%) patients after gene therapy. Major amputation was not required. There were no deaths and no major safety concerns.

CONCLUSION

Hepatocyte growth factor gene therapy is safe and effective for critical limb ischemia in patients with Buerger's disease.

Pretreatment by low-dose fibrates protects against acute free fatty acid-induced renal tubule toxicity by counteracting PPARα deterioration

Development of a preventive strategy against tubular damage associated with proteinuria is of great importance. Recently, free fatty acid (FFA) toxicities accompanying proteinuria were found to be a main cause of tubular damage, which was aggravated by insufficiency of peroxisome proliferator-activated receptor alpha (PPARα), suggesting the benefit of PPARα activation. However, an earlier study using a murine acute tubular injury model, FFA-overload nephropathy, demonstrated that high-dose treatment of PPARα agonist (0.5% clofibrate diet) aggravated the tubular damage as a consequence of excess serum accumulation of clofibrate metabolites due to decreased kidney elimination. To induce the renoprotective effects of PPARα agonists without drug accumulation, we tried a pretreatment study using low-dose clofibrate (0.1% clofibrate diet) using the same murine model. Low-dose clofibrate pretreatment prevented acute tubular injuries without accumulation of its metabolites. The tubular protective effects appeared to be associated with the counteraction of PPARα deterioration, resulting in the decrease of FFAs influx to the kidney, maintenance of fatty acid oxidation, diminution of intracellular accumulation of undigested FFAs, and attenuation of disease developmental factors including oxidative stress, apoptosis, and NFκB activation. These effects are common to other fibrates and dependent on PPARα function. Interestingly, however, clofibrate pretreatment also exerted PPARα-independent tubular toxicities in PPARα-null mice with FFA-overload nephropathy. The favorable properties of fibrates are evident when PPARα-dependent tubular protective effects outweigh their PPARα-independent tubular toxicities. This delicate balance seems to be easily affected by the drug dose. It will be important to establish the appropriate dosage of fibrates for treatment against kidney disease and to develop a novel PPARα activator that has a steady serum concentration regardless of kidney dysfunction.

Abstract P4-10-05: Factors Associated with Ipsilateral Breast Tumor Recurrence in Breast Cancer Patients Treated with Breast Conserving Surgery and Radiotherapy after Preoperative Chemotherapy

Background: Although preoperative chemotherapy (PCT) was originally used to make locally advanced breast cancers (BC) operable, it is now frequently utilized to make relatively large primary tumors small enough for breast conserving treatment (BCT). A large number of studies have been performed to identify risk factors of ipsilateral breast tumor recurrence (IBTR) after breast conserving treatment for originally small tumors. However, those studies for patients (Pts) who received BCT after PCT for relatively large tumors are limited. We have done a multicenter retrospective study to identify factors which were associated with IBTR in Pts treated with BCT after PCT.

Patients and methods: From 7 Japanese hospitals, data, which regard characteristics of tumors and Pts, and treatment, of Pts who fulfilled the following criteria; 1. Female BC Pts who started PCT before January 2007 2. Her tumor was invasive, clinically solitary, and 2 cm or largerby palpation at diagnosis 3. She received 3 or more cycles of PCT 4. She received breast conserving surgery as a definitive surgery after PCT including axillary dissection or sentinel node biopsy 5. She received radiotherapy at least to the conserved breast. Pts with inflammatory BC and BC Pts who received preoperative treatment(s) other than chemotherapy were excluded. Kaplan-Meier method was used to estimate cumulative recurrence rates. Log rank test and Cox's proportional hazard model were used for statistical analyses. Receiver Operating Characteristic (ROC) Curves and C statistics were used for evaluating the prediction ability of Cox's proportional hazard model about IBTR.

Results: A total of 324 Pts were registered. The median age at diagnosis of them was 48 years old. The median size of the primary tumors by palpation at diagnosis was 4 cm. For PCT anthracycline-based regimens were used for 83 Pts, taxane-based regimens were for 29, and anthracycline-taxane regimens were for 212. One hundred forty two Pts (43.8%) received postoperative chemotherapy, 180 (55.6%) had postoperative endocrine therapy, and only 7 had postoperative trastuzumab therapy. The median follow-up period was 45 months. Nineteen Pts (5.9%) developed IBTR. The cumulative 4-year IBTR rate was 5.5%. Univariate analyses revealed that estrogen receptor (ER) status both before and after PCT, pathological nodal status after PCT, and pathologically residual invasive tumor (solitary vs. multifocal, 1.7 cm or smaller vs. 1.8 cm or larger) were statistically significantly associated with IBTR (P &lt; 0.05 for all of them). Pathological margin status did not affect IBTR rate (P=0.73). ER status prior to PCT (positive vs. negative)(Hazard Ratio [HR], 6.76; P=0.012), size of the residual invasive tumor (1.7 cm or smaller vs. 1.8 cm or larger)(HR, 4.74; P=0.020), and pathological nodal status after PCT (0-3 positive nodes vs. 4 or more)(HR, 3.03; P=0.041) were associated with IBTR on multivariate analysis. C statistic was 78.3%.

Conclusion: Mastectomy may be a better choice for the Pts who have tumors with negative ER, pathologically large (1.8 cm or larger) residual invasive lesions after PCT, or 4 or more pathologically positive nodes after PCT in terms of local control.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-10-05.

Expression and localization of vascular endothelial growth factor in normal abdominal aorta and abdominal aortic aneurysm

AIM

The genesis of abdominal aortic aneurysms is associated with remodeling of the vascular wall by angiogenesis as well as proteolysis. Vascular endothelial growth factor (VEGF) is known to be a regulator of angiogenesis and to simultaneously stimulate elastolytic proteinases. We analyzed the expression and localization of VEGF in human abdominal aortic aneurysms compared to normal human aorta

METHODS

Eighteen infrarenal aortic aneurysm samples were collected at the time of abdominal aortic aneurysm surgery, while nine normal aortic samples were obtained from autopsy specimens. Immunohistochemical staining was performed to detect VEGF. Immunoenzyme or immunofluorescent double staining was also used to identify those cells presenting VEGF.

RESULTS

VEGF was expressed in 18 (100%) of the 18 abdominal aortic aneurysm samples, while 0 (0%) in the 9 normal abdominal aorta samples. Of the 18 samples of aneurysms, all 18 displayed positive VEGF immunostaining in macrophages, 12 in smooth muscle cells (SMCs), and 9 in endothelial cells (ECs).

CONCLUSION

Our study clearly demonstrated the expression of VEGF in ECs, and SMCs, and macrophages of abdominal aortic aneurysms as well as its absence in those cells of normal abdominal aorta, suggesting that VEGF may play an important role in aneurysm formation via its direct and/or indirect actions.

Prostaglandin receptors EP2 and IP are detectable in atherosclerotic arteries and plaques

AIM

Prostaglandin (PG) receptor agonists are frequently used for the pharmacological treatment of arteriosclerosis obliterans (ASO). In particular, the PG receptors EP2 and IP stimulate vasodilation and inhibit platelet aggregation, biological processes thought to be protective against ASO and important for physiological homeostasis. However it is uncertain whether EP2 and IP exist in diseased arteries, or what their distribution within the artery might be. In this study, we analyzed the distribution of these PG receptors in patients with severe ASO to determine the potential application of stimulation of these receptors as targets for pharmacological treatment.

METHODS

We collected segments of atherosclerotic femoral arteries during femoropopliteal bypass surgery and determined the expression levels of EP2 and IP receptors by western blotting. Immunofluorescence was used to observe receptor localization.

RESULTS

Findings of western blotting showed an increased Cox-2 expression in patients with ASO. The EP2 as well as IP receptors were each induced approximately 3-fold in comparison to normal samples. The expression of these receptors was increased in the intimal layer as well as the medial layer; their expression was also detectable within the atherosclerotic plaque.

CONCLUSION

We observed induction of the PG receptors EP2 and IP in atherosclerotic femoral arteries in the arterial intima, medial layer, as well as the associated atherosclerotic plaque. These results suggest that receptor-selective PG agonists specifically target atherosclerotic arteries and therefore, may find potential application in the pharmacological management of patients with ASO.

Three-year cardiovascular events and disease progress in patients with peripheral arterial disease: results from the Japan Medication Therapy for Peripheral Arterial Disease (J-METHOD)

AIM

To investigate the current status of peripheral arterial disease (PAD) drug treatment in Japan, and the effects of drug treatment, risk factors, and complications on disease progress and onset of cardiovascular events in PAD patients.

METHODS

In this prospective observational cohort study, 557 PAD patients were followed up for 3 years, and the current status of PAD treatment, risk factors, and cardiovascular events were monitored.

RESULTS

Three drugs, i.e., beraprost sodium, cilostazol, and aspirin, were most frequently used. The patients who had undergone vascular reconstruction of the lower limbs before enrollment showed significant improvement in ABI. Among the patients who had not undergone vascular reconstruction before enrollment, there was a significant improvement in ABI after treatment with beraprost. During the observation period, cardiovascular deaths occurred in 35 patients (6.3%), heart diseases in 63 (11.3%), brain diseases in 39 (7.0%), and events in the lower limbs in 94 (16.9%). The factors affecting the increase of the cardiovascular events were explored by multivariate analysis (Cox regression analysis). As a result, age (75 years or older), ischemic heart disease and increase in severity on the Fontaine classification were identified as significant factors for cardiovascular deaths, whereas kidney disorders and increase in severity on the Fontaine classification were identified for heart diseases, the number of oral drugs for treating PAD was identified for brain diseases, and age (younger than 75 years), dialysis, ABI (less than 0.7) and aspirin were identified for the events in the lower limbs.

CONCLUSION

As a result of the three-year follow-up on the Japanese PAD cohort, the current status of PAD treatment, risk factors, and cardiovascular events could be identified.

The education system to master endovascular aortic repair in Japan - the Japanese Committee for Stentgraft Management

OBJECTIVE

The Japanese Committee for Stentgraft Management (JACSM) was established with the aim of ensuring the safe and proper reach of commercial stent grafts following their regulatory approval. This study examines the validity of the practice standards developed by JACSM.

METHODS

JACSM comprises 10 associations related to endovascular treatment. Based on the practice standards developed by JACSM, the status of practising institutions, practising surgeons, supervising surgeons and the results of follow-up surveys were analysed.

RESULTS

In the 2.5 years following the establishment of JACSM, 298 institutions have fulfilled the practice standards. The number of practising surgeons reached 493, and the number of supervising surgeons reached 177. There were 3089 registered cases up to June 2009. The present study analysed 1570 cases registered in the 2 years from July 2006 to June 2008. The hospital mortality rate was low (0.4%) in the follow-up surveys.

CONCLUSIONS

Early results following the introduction of stent grafts were generally good. The procedure spread safely without the learning curve seen in the initial stages following introduction of new medical materials, indicating that the practice standards were appropriate.

Granulomatous transformation of capillary lesions in pulmonary-renal syndrome autologously induced anti-glomerular basement membrane disease in Wistar-Kyoto rats

BACKGROUND

Pulmonary-renal syndrome is characterized by pulmonary hemorrhage and rapidly progressive glomerulonephritis in various immunological states. Histopathological analysis of pulmonary-renal syndrome is not yet complete.

METHODS

Wistar-Kyoto (WKY) rats were sensitized using the noncollagenous (NC1) domain of type IV collagen from bovine kidney as an antigen. Histopathology of the kidneys and lungs was investigated with light microscopy, immunohistochemistry and electromicroscopy. Expression levels of cytokine mRNA were determined by real-time RT-PCR using renal tissue of rats.

RESULTS

Macrophage-rich granulomatous glomerulonephritis and alveolar capillaritis accompanied with pulmonary hemorrhage were induced by the sensitization. The humoral antibody against NC1 was detected on the glomerular and alveolar capillary walls. Th2 cytokine IL-10 was dominant over Th1 cytokine IFN-gamma in renal tissues of WKY rats.

CONCLUSION

The granulomatous transformation seemed to be induced by macrophage conspicuous capillaritis under dominant cellular immune reactions in WKY rats. In addition to Th1 cytokines, Th2 cytokines may also participate in the formation of granulomatous lesions.

Kidney dysfunction induced by protein overload nephropathy reduces serum sulfatide levels in mice

We recently proposed serum sulfatides as a novel biomarker for cardiovascular disease in patients with end-stage renal failure (ESRF), based on the possible antithrombotic properties of this molecule. In this earlier study, the level of serum sulfatides was gradually decreased in parallel with kidney dysfunction; however the precise mechanism underlying this decrease was unknown. The aim of the present study was to investigate the mechanism underlying the decrease in serum sulfatide levels caused by kidney dysfunction in an experimental animal model. To produce a kidney dysfunction animal model, we prepared a mouse model of protein overload nephropathy. Using high-throughput analysis combined with matrix-assisted laser desorption ionisation time-of-flight mass spectrometry, we measured the levels of sulfatides in the sera, livers, small intestines and kidneys of protein overload nephropathy mice. As the disease progressed, the levels of sulfatides in sera decreased. Also, the levels in livers and small intestines decreased in a similar manner to those in sera, to approximately 60% of the original levels. On the contrary, those in kidneys increased by approximately 1.4-fold. Our results indicate that kidney dysfunction affects the levels of sulfatides in lipoprotein-producing organs, such as livers and small intestines, and lowers the levels of sulfatides in sera.

Clinical comparison of two different types of bifurcated graft for postoperative baPWV and ABI

AIM

A newly-designed bifurcated graft with the distal end larger than the conventional type has been developed. The purpose of this study was to evaluate the early results of graft replacement using this new graft, and to compare whether the new graft is more advantageous than the conventional graft in terms of peripheral blood flow and arterial stiffness.

METHODS

Records of 36 patients who underwent bifurcated graft replacement for infrarenal abdominal aortic aneurysm (AAA), from May 2003 to September 2006 were reviewed after excluding peripheral arterial disease (ABI > 0.9). Subjects were divided into two groups: group C (N.=20), with implantation of the conventional type and group N (N.=16), with implantation of the new type. We investigated changes in brachial-ankle pulse wave velocity (baPWV) and ankle-brachial pressure index (ABI), measurements being performed preoperatively and postoperatively.

RESULTS

baPWV in the postoperative group as a whole was significantly higher than in the preoperative group (P<0.05), while ABI in the postoperative group was lower than in the preoperative group (P<0.05). In group C, baPWV increased (P<0.05) and ABI decreased (P<0.05) after bifurcated graft replacement, whereas in group N, there were no significant differences in changes of baPWV and ABI.

CONCLUSIONS

This study shows that the new graft reduces the development of arterial stiffness postoperatively compared with the conventional type. These results may predict the new type graft decrease in the risk of morbidity and mortality caused by atherosclerotic disease.

Sentinel node biopsy in Asian breast cancer patients: An observation study of 1,000 consecutive patients treated at a single institute

e11584

Background: In woman with breast cancer, sentinel lymph node (SLN) biopsy (SLNB) provides staging information and a favorable effect on quality of life if the SLN does not have metastasis. While many reports already showed safety and reliability about SLNB for breast cancer patients in Western countries, few reports have published from Asian countries. Our purpose of this study is to prove the technical success, accuracy and safety of this method for Asian population. Methods: We did feasibility study of 183 patients from 2000 to 2002. After that, we evaluated detection rate, positive rate, axillary relapse rate in 1,000 consecutive patients who underwent sentinel lymph node biopsy for breast cancer at a single institute in Japan from 2002 to August 2008. In this series, both radioactive agent (technetium) and vital blue die (indigocarmine) were used to investigate the SLNs. Results: We could accurately predict SLNs in 994 (99.4%) of the 1,000 patients. The proportion of technical success was high regardless of surgeon's experience. Intraoperative frozen section histology showed that positive SLNs were found in 176 (17.7%) patients (13 micrometastasis and 163 macrometastasis). Defenitive histology found metastasis in 24 cases who defined as negative by the frozen section examination. 15 of 24 (62.5%) cases underwent delayed axillary lymph node dissection (ALND) after definitive histology. The histological concordance between frozen section and permanent sections of SLNs was 97.6%. Finally, 796 patients were followed up without ALND. With a median follow-up time of 3.5 years (0.5–5.2), axillary lymph node recurrence were occurred in 5 patients (5 of 796, 0.6%). The relapse time since SLNB ranged from 16 to 33 months. There were not any patients with allergic reactions. Conclusions: This is the report about observation study including more than 1,000 patients from Asian country. SLNB is seemed to be a safe and acceptably accurate method for Asian early breast cancer patients.

No significant financial relationships to disclose.

PPAR{alpha} attenuates the proinflammatory response in activated mesangial cells

The activated mesangial cell is an important therapeutic target for the control of glomerulonephritis. The peroxisome proliferator-activated receptor alpha (PPARalpha) has attracted considerable attention for its anti-inflammatory effects; however, its roles in the mesangial cells remain unknown. To determine the anti-inflammatory function of PPARalpha in mesangial cells, wild-type and Ppara-null cultured mesangial cells were exposed to lipopolysaccharide (LPS). LPS treatment caused enhanced proinflammatory responses in the Ppara-null cells compared with wild-type cells, as revealed by the induction of interleukin-6, enhanced cell proliferation, and the activation of the nuclear factor (NF)-kappaB signaling pathway. In wild-type cells resistant to inflammation, constitutive expression of PPARalpha was undetectable. However, LPS treatment induced the significant appearance and substantial activation of PPARalpha, which would attenuate the proinflammatory responses through its antagonizing effects on the NF-kappaB signaling pathway. The induction of PPARalpha was coincident with the appearance of alpha-smooth muscle actin, which might be associated with the phenotypic changes of mesangial cells. Moreover, another examination using LPS-injected wild-type mice demonstrated the appearance of PPARalpha-positive cells in glomeruli, suggesting in vivo correlation with PPARalpha induction. These results suggest that PPARalpha plays crucial roles in the attenuation of inflammatory response in activated mesangial cells. PPARalpha might be a novel therapeutic target against glomerular diseases.

Antigenicity of sulfanilamide and its metabolites using fluorescent-labelled compounds

In order to clarify the onset mechanisms of drug-induced allergies, three fluorescent-labelled compounds were synthesized by subjecting sulfanilamide (SA), a base compound for sulfonamides, and its active metabolites, i.e. sulfanilamide hydroxylamine and sulfanilamide nitroso, to dansylation using dansylchloride. In other words, 5-dimethylamino-N-(4-aminobenzyl)-naphthalenesulfonamide (DNS-4ABA), 5-dimethylamino-N-(4-hydroxylaminobenzyl)-1-naphthalenesulfonamide (DNS-4HABA) and 5-dimethylamino-N-(4-nitrosobenzyl)-1-naphthalenesulfonamide (DNS-4NSBA) were synthesized as model haptens. When analysed by HPLC, a conjugate of DNS-4HABA and glutathione (GSH) with nucleophilic amino acids had two peaks (P-1 and P-2). FAB-MS and 1H-NMR revealed that the DNS-4HABA-GSH conjugate consisted of sulphinamide and semimercaptal. The reactivity of GSH to DNS-4ABA, DNS-4HABA and DNS-4NSBA was quantified by HPLC using an oxidization system (horseradish peroxidase/H2O2). The results show that production of DNS-4NSBA-GSH-conjugate was four to eight times higher than that of DNS-4HABA-GSH conjugate, but that DNS-4ABA did not bind with GSH. Skin reactions were assessed using guinea pigs, and strong delayed erythema was seen with DNS-4NSBA, which bound most strongly with GSH, whereas weak delayed erythema was seen with DNS-4ABA, which did not bind with GSH. This suggests a correlation between GSH conjugate production and skin reactions. DNS-4HABA enzymatically bound with proteins in rat and guinea pig liver cytosol and microsomal fractions. The proteins that bound to DNS-4HABA were purified by HPLC and then subjected to N-terminal amino acid analysis. Ubiquitin (10 kDa) and fatty acid binding protein (30 kDa) were detected in the rat liver cytosol fraction; retinol-dehydrogenase (35 kDa) in the rat microsomal fraction; and glutathione-S-transferase B (mmu) (25 kDa) in the guinea pig liver cytosol fraction. When DNS-4HABA or DNS-4NSBA binds to proteins that play important roles in the body, unexpected adverse reactions may occur. Furthermore, by utilizing our technique using model compounds, it may be possible to identify the carrier proteins of various compounds, including pharmaceutical agents.

Renal pathology of ANCA-related vasculitis: proposal for standardization of pathological diagnosis in Japan

BACKGROUND

In Japan, systematic evaluation of the histologic parameters of anti-neutrophil cytoplasmic autoantibodies (ANCA)-related vasculitis has been performed according to the Japanese classification by Shigematsu et al. However, this classification is quite different from that of the European Vasculitis Study Group (EUVAS) classification. Therefore, a histological common basis is needed to compare Japanese histological data with the international database.

METHOD

Histological parameters concerning glomerular, tubulointerstitial, and vascular lesions of ANCA-related vasculitis, which are indispensable for clinical management, were elucidated and defined by reviewing, utilizing the merits of, and amending the two scoring systems.

RESULTS AND CONCLUSION

A new comprehensive and standardized scoring system, by which histological quantitative assessment can provide evidence for therapy planning, has been developed for renal biopsy of Japanese ANCA-related vasculitis.

Mast cells in the kidney

Mast cells have become a recent concern in the nephrological world. The development of antibodies to mast cell-specific enzymes, tryptase and chymase, has facilitated the study of mast cells in the kidney. Now, they are investigated immunohistochemically as well as histochemically. There are three types of human mast cells, MC(T), which contains exclusively tryptase, MC(TC), which has both tryptase and chymase, and MC(C), which contains only chymase. Many immunohistochemical studies involving mast cells have been conducted through the use of renal biopsy specimens. As a result, human renal diseases including various glomerulonephritis and pyelonephritis are found to have increased the number of mast cells in the renal cortex, especially in the area of fibrosis. The relationship between the number of mast cells and the prognosis of renal diseases has been proved to be significantly correlated in many reports. The subtypes of mast cells in these diseases are variably present, and no tendency of subtype specificity has been found. With the use of electron microscopically, mast cells are observed to be in contact with other interstitial cells or to infiltrate into tubules. Functionally, human renal mast cells resemble lung mast cells. Inhibitory substances for mast cell proliferation have been found in the mouse kidney. Compared with the results of human studies, mast cells are not found in the interstitum in animal models of renal diseases, except in a few transgenic mouse models and magnesium-deficient rats. Little is known about the exact roles that mast cells play in the renal interstitium. Future studies will hopefully make their characteristics clear.