Examination of mitral regurgitation with a goat heart model for the development of intelligent artificial papillary muscle

Annuloplasty for functional mitral or tricuspid regurgitation has been made for surgical restoration of valvular diseases. However, these major techniques may sometimes be ineffective because of chamber dilation and valve tethering. We have been developing a sophisticated intelligent artificial papillary muscle (PM) by using an anisotropic shape memory alloy fiber for an alternative surgical reconstruction of the continuity of the mitral structural apparatus and the left ventricular myocardium. This study exhibited the mitral regurgitation with regard to the reduction in the PM tension quantitatively with an originally developed ventricular simulator using isolated goat hearts for the sophisticated artificial PM. Aortic and mitral valves with left ventricular free wall portions of isolated goat hearts (n=9) were secured on the elastic plastic membrane and statically pressurized, which led to valvular leaflet-papillary muscle positional change and central mitral regurgitation. PMs were connected to the load cell, and the relationship between the tension of regurgitation and PM tension were measured. Then we connected the left ventricular specimen model to our hydraulic ventricular simulator and achieved hemodynamic simulation with the controlled tension of PMs.

Unique mechanisms of excitation energy transfer, electron transfer and photoisomerization in biological systems

We discuss unique mechanisms typical in the elementary processes ofbiological functions. We focus on three topics. Excitation energytransfer in the light-harvesting antenna systems of photosyntheticbacteria is unique in its structure and the energy transfer mechanism. Inthe case of LH2 of Rhodopseudomonas acidophila, the B850 intra-ringenergy transfer and the inter-ring energy transfer between B800 and B850take place by the intermediate coupling mechanism of energy transfer. Theexcitonic coherent domain shows a wave-like movement along the ring, andthis property is expected to play a significant role in the inter-ringenergy transfer between LH2's. The electron transfer in biological systemsis mostly long-range electron transfer that occurs by the electrontunneling through the protein media. There is a long-standing problem thatwhich part of protein media is used for the electron tunneling root. As aresult of our detailed analysis, we found that the global electron tunnelingroot is a little winded with a width of a few angstrom, reflecting theproperty of tertiary and secondary structures of the protein and it isaffected by the thermal fluctuation of protein structure. Photoisomerizationof rhodopsin is very unique: The cis-transphotoisomerization ofrhodopsin occurs only around the C11 = C12 bond in the counterclockwisedirection. Its molecular mechanism is resolved by our MD simulation studyusing the structure of rhodopsin which was recently obtained by the X-raycrystallographic analysis.

Serum undercarboxylated osteocalcin level increases with 48 weeks of teriparatide treatment in pre-treated elderly rheumatoid arthritis patients who use anti-resorptive drugs

AIM

The serum undercarboxylated osteocalcin (ucOC) level, a biochemical bone marker of vitamin K insufficiency, is often affected by anti-osteoporosis drugs. There have been no reports regarding the relationship between ucOC and teriparatide.

SUBJECTS AND METHODS

We conducted a prospective observational study of 26 female rheumatoid arthritis (RA) patients. The patients were divided into 3 groups: those who underwent a direct switch from anti-resorptive drugs to teriparatide (12 cases), those who started teriparatide without pre-treatment (5 cases), and the control patients (9 cases). The median age (interquartile range) of the patients in each group was 75 (67-77), 82 (78-84), and 69 (62-80) yr, respectively. All patients, except controls, received 48-week treatments of teriparatide. We analyzed the median 48-week changes from baseline of the serum ucOC levels with the Steel-Dwass method.

RESULTS

The median change from baseline in the direct switch group was higher than that in other groups (p<0.05).

CONCLUSIONS

The serum ucOC levels increased with treatment of teriparatide in elderly RA patients, especially when the patients received pre-treatment.

Cell dynamics in cervical loop epithelium during transition from crown to root: implications for Hertwig's epithelial root sheath formation

BACKGROUND AND OBJECTIVE

Some clinical cases of hypoplastic tooth root are congenital. Because the formation of Hertwig's epithelial root sheath (HERS) is an important event for root development and growth, we have considered that understanding the HERS developmental mechanism contributes to elucidate the causal factors of the disease. To find integrant factors and phenomenon for HERS development and growth, we studied the proliferation and mobility of the cervical loop (CL).

MATERIAL AND METHODS

We observed the cell movement of CL by the DiI labeling and organ culture system. To examine cell proliferation, we carried out immunostaining of CL and HERS using anti-Ki67 antibody. Cell motility in CL was observed by tooth germ slice organ culture using green fluorescent protein mouse. We also examined the expression of paxillin associated with cell movement.

RESULTS

Imaging using DiI labeling showed that, at the apex of CL, the epithelium elongated in tandem with the growth of outer enamel epithelium (OEE). Cell proliferation assay using Ki67 immunostaining showed that OEE divided more actively than inner enamel epithelium (IEE) at the onset of HERS formation. Live imaging suggested that mobility of the OEE and cells in the apex of CL were more active than in IEE. The expression of paxillin was observed strongly in OEE and the apex of CL.

CONCLUSION

The more active growth and movement of OEE cells contributed to HERS formation after reduction of the growth of IEE. The expression pattern of paxillin was involved in the active movement of OEE and HERS. The results will contribute to understand the HERS formation mechanism and elucidate the cause of anomaly root.

Post-menopausal women with rheumatoid arthritis who are treated with raloxifene or alendronate or glucocorticoids have lower serum undercarboxylated osteocalcin levels

BACKGROUND

Serum undercarboxylated osteocalcin (ucOC) is a biochemical bone marker of vitamin K insufficiency. It had been reported that bone resorption inhibitors tend to decrease the serum ucOC level in patients with primary osteoporosis. In rheumatoid arthritis (RA) patients, these results have never been reported.

AIM

We investigated risk factors which could change serum ucOC level in post-menopausal women with RA (no.=100).

SUBJECTS AND METHODS

Twenty patients received no bone resorption inhibitor (control), 30 received raloxifene (RLX), while 50 received alendronate (ALN). This cross-sectional study was limited to patients with low RA disease activity (Disease Activity Score-28 ≤3.2). We measured serum ucOC, and the data were analyzed by multivariable analysis, including ucOC and the other variables.

RESULTS

Scheffe's F test demonstrated a significant difference in serum ucOC levels between controls and the RLX group (p<0.01), and between controls and the ALN group (p<0.01). Serum ucOC levels were low in both treated groups. An adjusted multivariate analysis was performed for the variables: bone resorption inhibitor use, serum alkaline phosphatase, glucocorticoid dose, age, estimated glomerular filtration rate and matrix metalloproteinase 3. As a result, serum ucOC inversely correlated with bone resorption inhibitor use (p<0.01) and oral glucocorticoid dose (p<0.01), which were independent risk factors of lowering ucOC.

CONCLUSIONS

Bone resorption inhibitors and glucocorticoids were independent risk factors for lowering serum ucOC levels in post-menopausal RA patients.

Recurrence of colonic diverticular bleeding and associated risk factors

AIM

Colonic diverticular bleeding often recurs, but the risk factors remain unclear. Our aim was to identify risk factors for recurrence in patients with diverticular bleeding.

METHOD

Seventy-two hospitalized patients who were diagnosed with diverticular bleeding between 2004 and 2008 were analyzed. Rebleeding was considered as the main outcome measure, with the duration until recurrence identified from medical records. Potential risk factors for rebleeding, such as underlying pathologies, medication and smoking and drinking habits, were investigated from the medical records on initial admission.

RESULTS

Of the 72 patients, 19 had a diverticular disease on the right, 16 on the left side and 37 on both sides of the colon. Recurrence was identified in 27 (38%) patients at a median interval of 1535 days. The cumulative incidence of rebleeding at 6, 12 and 24 months was 15%, 20% and 33%. Multivariate analysis revealed nonsteroid anti-inflammatory drugs (NSAIDs) (hazard ratio (HR), 2.57; 95% confidence interval (CI), 0.89-7.46; P=0.08), antiplatelet drugs (HR, 2.39; 95% CI, 1.01-5.67; P=0.05) and hypertension (HR, 4.16; 95% CI, 1.22-14.2; P=0.02) to be risk factors for rebleeding.

CONCLUSION

Patients with colonic diverticular bleeding show high recurrence rates within a short period. Risk factors for recurrence have been identified as the use of NSAIDs or antiplatelet drugs and hypertension.

P5-13-23: Individualized Treatment Strategies for HER2−Negative Breast Cancer Subtypes

Background Human epidermal growth factor receptor (HER2)-negative breast cancers are more heterogeneous than HER2−positive cancers, and tailored treatment is therefore required for luminal A and triple-negative breast cancer subtypes (LABC and TNBC). We therefore examined predictive factors for the efficacy of standard chemotherapy in LABC and TNBC subtypes.

Methods A total of 109 LABC and 61 TNBC patients were treated with standard neoadjuvant chemotherapy (NAC) consisting of an anthracycline and/or taxane. The pathological treatment response and prognosis were examined for each subtype. Expression levels of the following factors were examined in association with quasi-pathological complete response (QpCR): estrogen- and progesterone-receptor (ER and PgR) status, HER2, nuclear grade, MIB-1, p53, topoisomerase IIα (topoIIα), cytokeratin (CK) 5/6 and epidermal growth factor (EGFR).

Results QpCR rates in LABC and TNBC were 9.1% (10/109) and 54.1% (33/61), respectively. In LABC, the expression of PgR tended to be inversely associated with pathological response (p=0.087), while in TNBC, increased expression of topoIIa (p=0.006) and MIB-1 (p=0.018) were identified as predictors of QpCR. TopoIIα expression was also significantly associated with pathological response in multivariate analysis (p=0.014). The QpCR rate was higher in TNBC lacking CK5/6 and/or EGFR expression, defined as non-basal subtype (p=0.053).

Conclusions Low expression of PgR may be a possible predictor of the efficacy of chemotherapy in LABC, while a high level of proliferative activity, indicated by topoIIa and MIB-1, is associated with chemosensitivity in TNBC. Further subclassification into basaland non basal-subtypes may also be helpful for the development of individualized treatments.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-13-23.

Second-order autocorrelation of XUV FEL pulses via time resolved two-photon single ionization of He

Second-order autocorrelation spectra of XUV free-electron laser pulses from the Spring-8 Compact SASE Source (SCSS) have been recorded by time and momentum resolved detection of two-photon single ionization of He at 20.45 eV using a split-mirror delay-stage in combination with high-resolution recoil-ion momentum spectroscopy (COLTRIMS). From the autocorrelation trace we extract a coherence time of 8 ± 2 fs and a mean pulse duration of 28 ± 5 fs, much shorter than estimations based on electron bunch-length measurements. Simulations within the partial coherence model [Opt. Lett. 35, 3441 (2010)] are in agreement with experiment if a pulse-front tilt across the FEL beam diameter is taken into account that leads to a temporal shift of about 6 fs between both pulse replicas.

Seroprevalence of tularemia in wild bears and hares in Japan

Tularemia is a zoonotic disease caused by Francisella tularensis. The distribution of the pathogen in Japan has not been studied well. In this study, seroprevalence of tularemia among wild black bears and hares in Japan was determined. Blood samples collected from 431 Japanese black bears (Ursus thibetanus japonicus) and 293 Japanese hares (Lepus brachurus) between 1998 and 2009 were examined for antibodies against F. tularensis by micro-agglutination test (MA) or enzyme-linked immunosorbent assay. By subsequent confirmatory tests using western blot (WB) and indirect immunofluorescence assay (IFA), eight sera from Japanese black bears were definitely shown to be seropositive. All of these eight bears were residents of the northeastern part of main-island of Japan, where human tularemia had been reported. On the other hand, no seropositive Japanese hares were found. These results suggest that Japanese black bears can serve as sentinel for tularemia surveillance and may help understand the distribution of F. tularensis throughout the country. This is the first report on detection of antibody to F. tularensis in black bears of Japan.

Improvement of film Quality of A-Si:H Deposited by Photo-CVD using SiH2Cl2

Hydrogenated Amorphous silicon films (a-Si:H) were prepared by mercury sensitized photo-CVD using SiH4 and SiH2Cl2 gas mixture. The effects of chlorine (Cl) on the electrical, optical and structural properties of the a-Si:H films were investigated. It was found that a small addition of SiH2Cl2 to the deposition system increases the photo-sensitivity, decreases the defect density, and reduces the light induced degradation of a-Si:H films. At a large addition of SiH2Cl2, however, the CI incorporation into the films was observed, resulting in the deterioration of the film properties. The electrical and optical properties were successfully improved by the H2 dilution when the films were deposited with a large addition of SiH2Cl2.

Bandgap Engineering of ZnO Transparent Conducting Films

Low resistivity and transparent Al doped ZnMgO films were deposited on glass substrates by a pulsed laser deposition system. For up to 32 atm% of Mg content, segregation of a MgO phase was not observed. The bandgap of these films could be widened to about 4 eV with increasing Mg content. The relation between bandgap and resistivity was found to be a trade-off; i.e. the larger the bandgap, the higher the resistivity. The maximum bandgap among films with an electrical resistivity of less than 10-3 Ω cm was 3.94 eV. The average optical transmittance of these films was more than 90 % for wavelengths λ between 400 and 1100 nm. The transmittance around λ = 330 nm was still 50 %.

Structural design of a newly developed pediatric circulatory assist device for Fontan circulation by using shape memory alloy fiber

Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary circulatory assist device by using shape memory alloy fibers. We developed a pulmonary circulatory assist device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary circulatory assist device. The diameter of this fiber was 100 microns, and its contractile frequency was 2-3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10 mmHg loading.

Abstract P1-01-16: Evaluation of Sentinel Node Biopsy Using a Combined Dye and Fluorescence Method for Breast Cancer

Background: Sentinel lymph node (SLN) dissection is now widely accepted for staging the axilla in patients with breast cancer. At present, several methods are used to detect SLN. A combination of blue dye and radioactive colloid has been described previously as a superior method for detecting SLN in breast cancer patients. However, use of radioactive colloids is not generally available for various reasons in Japan. SLN detection guided by indocyanine green (ICG) fluorescence could emerge as a new method for SLN biopsy. The aim of this study was to evaluate sentinel node biopsy using a combined dye and fluorescence method for breast cancer.

Methods: Fifty-eight patients with clinically node-negative breast cancer were examined between April 2008 and March 2009 at Yokohama City University Hospital. Intradermal injections of 20 mg/5 ml of indigo carmine and 0.5 mg/0.1 ml of ICG were made into the upper-lateral region of the periareolar area. Subcutaneus lymphatic channels draining from the areola to the axilla were visible under fluorescence within a few minutes. SLNs were then dissected under direct vision supported by fluorescence navigation. Palpable lymph nodes were also dissected. All SLNs were histologically evaluated by 2-mm serial section and staining with hematoxylin and eosin. Patients with positive SLNs underwent axillary lymph node dissection (ALND), while patients with negative SLN did not.

Results: SLNs were identified in 58 patients (100%). ICG fluorescence imaging was compared with indigo carmine dye, and SLNs were identified in 57 and 52 patients, respectively (detection rate: ICG, 98.3%; dye, 89.7%). The mean number of excised SLNs was 2.72. Mean numbers of lymph nodes showing fluorescence and blue stain from injected dye were 2.31 and 1.41, respectively. Eight of 58 patients (13.8%) had metastases detected in the SLN, so ALND were subsequently performed. Five of these cases were without metastases at non-SLN that were dissected. One patient showed metastasis in a SLN that was positive for fluorescence, but negative for blue dye. Among all cases, 1 patient (1.7%) showed an SLN without fluorescence or blue staining, and this case was detected by palpation only.

Conclusion: Combined use of dye and fluorescence method identified SLNs effectively.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-16.

Abstract P1-12-01: Preoperative Endocrine Therapy with Tamoxifen and Goserelin Acetate for Hormone Receptor-Positive Premenopausal Patients

Background: Clinical trials have consistently shown that the response rates of hormone receptor-positive breast cancer patients to neoadjuvant chemotherapy are low. Preoperative endocrine therapy has therefore become a logical alternative for such patients. Several researchers have reported favorable response rates in postmenopausal women. However, the effectiveness of preoperative endocrine therapy for premenopausal women remains unknown. The aim of this study was to evaluate the potential benefits of preoperative endocrine therapy for premenopausal women.

Materials and methods: Forty premenopausal patients with operable estrogen receptor (ER)-positive breast cancer were consecutively treated with neoadjuvant therapy with tamoxifen and Goserelin acetate for 3 months. The patients eligible for this study included clinically node-negative patients with tumors that were less than 2 cm in diameter and negative for human epidermal growth factor receptor 2 (HER2). All the patients were clinically evaluated using ultrasonograpy before and after the endocrine therapy. Further, core-needle biopsy specimens obtained before administration of the endocrine therapy and surgical specimens were pathologically evaluated for ER, progesterone receptor (PgR), HER2, p53, and Ki67 expressions. This study was approved by our institutional IRB.

Results: The patients included in this study were 30-52 years old (median age, 43 years). The size of the tumor was 0.9-2.0 cm (median, 1.5 cm).

The clinical response rate was 20% (8/40) and disease progression was not observed. In the case of 39 of the 40 patients, grade 0 or grade 1 pathological response was observed. Clinical responses were not correlated with pathological responses. The ER expression level before the endocrine therapy differed from that after the therapy in the case of 8% (2/40) of the patients (increased in 4% and decreased in 4%). Further, PgR expression was altered in the case of 50% (20/40) of the patients (increased in 8% and decreased in 42%). Moreover, Ki67 expression was decreased in 90% (36/40) of the patients after the endocrine therapy.

Conclusions: This is the first report on neoadjuvant endocrine therapy for premenopausal patients. Disease progression 3 months after the endocrine therapy was not observed. Because the expressions of Ki67 and PgR decreased, these molecules might be candidate markers of endocrine responsiveness in premenopausal patients. To confirm this assumption, further evaluations involving tumors of a larger size, longer observational period, and more number of eligible patients are planned to be conducted.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-12-01.

Oil microsealing: a robust micro-compartmentalization method for on-chip chemical and biological assays

A simple and robust method to compartmentalize aqueous solutions into an array of independent microchambers is presented. The array of microchambers fabricated in poly(dimethylsiloxane) are filled with the sample solution through a microfluidic channel and then sealed with oil to isolate the microchambers from each other. A water reservoir close to the microchambers allows the maintainance and incubation of sub-nanoliter solutions (e.g., at 37 °C) within the chambers for hours without any problem of evaporation. Once assembled, the device is self-sustainable and can be used for different application purposes. As a demonstration, the device configuration is shown to be suitable for spatiotemporal control of the inner solution conditions by light stimulation through a photomask. This method was applied for the generation of regular EmGFP (emerald green fluorescent protein) expression arrays, selective photobleaching, photopatterning of calcium concentration, and cell culture in independent microchambers.

Histological contribution of collagen architecture to beef toughness

The relationship between shear-force value and collagen architecture of connective tissue of the longissimus thoracis (LT) muscle of Japanese Black (n = 10) and Brown (Kumamoto) (n = 5) steers (body weight: 688.4 +/- 8.6 kg as average and standard error) was investigated. There were negative correlations between the shear-force value and lipid content (n = 15, R(2)= 0.3709, P < 0.01) and protein content and lipid content (n = 15, R(2)= 0.6748, P < 0.01). Shear-force value and collagen content (n = 15, R(2)= 0.4344, P < 0.01) were positively correlated. In scanning electron microscopic photographs of the macerated preparation, the perimysium of the high-lipid LT muscle was broken down compared with the low-lipid LT muscle. The endomysium in all LT muscle fibers showed similar architecture. The fine surface cover of reticular collagen fibers around an adipocyte was observed in the high-lipid LT muscle perimysium. These results suggested that the shear-force value of the LT muscle was related to change in collagen architecture and of the perimysium in particular.

Time-resolved tracking of a minimum gene expression system reconstituted in giant liposomes

Individual expression: We describe a method that allows the observation of real-time gene expression in a large number of individual giant liposomes encapsulating identical genetic material. We followed the gene expression profiles from DNA and mRNA templates coding for different proteins. Although the average profiles of individual liposomes were similar to those measured in bulk solution, strong variability between individual liposomes was observed at both transcription and translation.

Evaluation of the 24-hour profiles of physiological insulin, glucose, and C-peptide in healthy Japanese volunteers

BACKGROUND

Some studies have demonstrated the benefit of blood glucose control as close as possible to physiological conditions. Not enough reports have investigated in detail the 24-h plasma profiles of insulin/glucose/C-peptide. Here we investigated the 24-h plasma profiles of physiological insulin/glucose/C-peptide in healthy Japanese adults.

METHODS

In order to evaluate the 24-h profiles of physiological insulin/glucose/C-peptide profiles, 42 blood samples were taken from each subject in our group of healthy Japanese volunteers to measure the 24-h profile with three standardized meals.

RESULTS

Plasma glucose and insulin increased rapidly followed by a rapid decrease after each meal with little variation at night. The average peak values of insulin after each meal were as follows: 426.20 pmol/L (breakfast), 373.75 pmol/L (lunch), and 410.28 pmol/L (dinner). The average times to peak insulin were 0.651 h (breakfast), 0.677 h (lunch), and 0.689 h (dinner). The corresponding average maximum postprandial plasma glucose levels were 8.39 mmol/L (breakfast), 8.77 mmol/L (lunch), and 8.74 mmol/L (dinner). The average times to peak glucose were 0.738 h (breakfast), 0.650 h (lunch), and 0.625 h (dinner). The average maximum postprandial C-peptide levels were 2.64 nmol/L (breakfast), 2.55 nmol/L (lunch), and 2.67 nmol/L (dinner). No major differences were found in these parameters between the Caucasian and Japanese populations.

CONCLUSIONS

This is the first investigation to measure the 24-h profiles of insulin/glucose/C-peptide in healthy Japanese volunteers with standardized meals. It is hoped this information will provide useful reference for future research and clinical management.

Pegylated interferon alpha-2b (Peg-IFN alpha-2b) affects early virologic response dose-dependently in patients with chronic hepatitis C genotype 1 during treatment with Peg-IFN alpha-2b plus ribavirin

Chronic hepatitis C (CH-C) genotype 1 patients who achieved early virologic response have a high probability of sustained virologic response (SVR) following pegylated interferon (Peg-IFN) plus ribavirin therapy. This study was conducted to evaluate how reducing drug doses affects complete early virologic response (c-EVR) defined as hepatitis C virus (HCV) RNA negativity at week 12. Nine hundred eighty-four patients with CH-C genotype 1 were enrolled. Drug doses were evaluated independently on a body weight base from doses actually taken. From multivariate analysis, the mean dose of Peg-IFN alpha-2b during the first 12 weeks was the independent factor for c-EVR (P = 0.02), not ribavirin. The c-EVR rate was 55% in patients receiving > or = 1.2 microg/kg/week of Peg-IFN, and declined to 38% at 0.9-1.2 microg/kg/week, and 22% in patients given <0.9 microg/kg/week (P < 0.0001). Even with stratified analysis according to ribavirin dose, the dose-dependent effect of Peg-IFN on c-EVR was observed, and similar c-EVR rates were obtained if the dose categories of Peg-IFN were the same. Furthermore, the mean dose of Peg-IFN during the first 12 weeks affected HCV RNA negativity at week 24 (P < 0.0001) and SVR (P < 0.0001) in a dose-dependent manner. Our results suggest that Peg-IFN was dose-dependently correlated with c-EVR, independently of ribavirin dose. Thus, maintaining the Peg-IFN dose as high as possible during the first 12 weeks can yield HCV RNA negativity and higher c-EVR rates, leading to better SVR rates in patients with CH-C genotype 1.