Mice lacking two sperm serine proteases, ACR and PRSS21, are subfertile, but the mutant sperm are infertile in vitro

Although sperm serine protease and proteasome have long been believed to play an important role in the fertilization process, the molecular mechanism is still controversial. In this study, we have produced double-knockout mice lacking two sperm serine proteases, ACR and PRSS21, to uncover the functional role of the trypsinlike activity in fertilization. The double-knockout male mice were subfertile, likely owing to the incompleteness of fertilization in the oviductal ampulla. Despite male subfertility, the mutant epididymal sperm exhibited the inability to undergo acrosomal exocytosis on the zona pellucida (ZP) surface and to traverse the ZP, thus resulting in the failure of fertilization in vitro. The double-knockout epididymal sperm were also defective in penetration through the cumulus matrix to reach the ZP. When epididymal sperm were artificially injected into the uterus of wild-type mice, the 2-cell embryos, which had previously been fertilized by double-knockout sperm, were recovered at a low but significant level. The mutant epididymal sperm were also capable of fertilizing the oocytes in the presence of uterine fluids in vitro. These data demonstrate that the trypsinlike protease activity of ACR and PRSS21 is essential for the process of sperm penetration through the cumulus matrix and ZP in vitro, and suggest that the female reproductive tract partially compensates for the loss of the sperm function. We therefore conclude that the sperm trypsinlike activity is still important but not essential for fertilization in vivo in the mouse.

Development of a population-based microsimulation model of osteoarthritis in Canada

OBJECTIVES

The purpose of the study was to develop a population-based simulation model of osteoarthritis (OA) in Canada that can be used to quantify the future health and economic burden of OA under a range of scenarios for changes in the OA risk factors and treatments. In this article we describe the overall structure of the model, sources of data, derivation of key input parameters for the epidemiological component of the model, and preliminary validation studies.

DESIGN

We used the Population Health Model (POHEM) platform to develop a stochastic continuous-time microsimulation model of physician-diagnosed OA. Incidence rates were calibrated to agree with administrative data for the province of British Columbia, Canada. The effect of obesity on OA incidence and the impact of OA on health-related quality of life (HRQL) were modeled using Canadian national surveys.

RESULTS

Incidence rates of OA in the model increase approximately linearly with age in both sexes between the ages of 50 and 80 and plateau in the very old. In those aged 50+, the rates are substantially higher in women. At baseline, the prevalence of OA is 11.5%, 13.6% in women and 9.3% in men. The OA hazard ratios for obesity are 2.0 in women and 1.7 in men. The effect of OA diagnosis on HRQL, as measured by the Health Utilities Index Mark 3 (HUI3), is to reduce it by 0.10 in women and 0.14 in men.

CONCLUSIONS

We describe the development of the first population-based microsimulation model of OA. Strengths of this model include the use of large population databases to derive the key parameters and the application of modern microsimulation technology. Limitations of the model reflect the limitations of administrative and survey data and gaps in the epidemiological and HRQL literature.

Functional roles of mouse sperm hyaluronidases, HYAL5 and SPAM1, in fertilization

Although sperm entry into the oocyte-cumulus complex and subsequent sperm penetration through the cumulus matrix to reach the oocyte zona pellucida are essential for mammalian fertilization, the molecular mechanism remains controversial. Previously, we have shown that mouse sperm lacking SPAM1 are capable of penetrating the cumulus matrix despite a delayed dispersal of cumulus cells. We also have identified another sperm hyaluronidase, HYAL5, as a candidate enzyme involved in sperm penetration through the cumulus. In the present study, we produced HYAL5-deficient mice to uncover the functional roles of HYAL5 and SPAM1 in fertilization. The HYAL5-deficient mice were fully fertile and yielded normal litter sizes. In vitro fertilization assays demonstrated that HYAL5-deficient epididymal sperm is functionally normal. We thus conclude that HYAL5 may be dispensable for fertilization. Comparative analysis among wild-type, HYAL5-deficient, and SPAM1-deficient epididymal sperm revealed that only SPAM1 is probably involved in sperm penetration through the cumulus matrix. Notably, the loss of SPAM1 resulted in a remarkably increased accumulation of sperm on the surface or outer edge of the cumulus. These data suggest that SPAM1 may function in sperm entry into the cumulus and sperm penetration through the cumulus matrix.

Definitive chemoradiation therapy with capecitabine in locally advanced pancreatic cancer

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Background: We evaluated safety and efficacy of concurrent chemoradiotherapy (CCRT) with capecitabine in patients with locally advanced pancreatic cancer (LAPC). We also tried to devise a prognostic model for LAPC undergoing definitive CCRT. Methods: Between January 2004 and January 2008, 39 patients with LAPC treated with capecitabine CCRT were reviewed. Capecitabine was administered at 850 mg/m2 bid every day for 5 weeks. Radiotherapy was given 5 days per week, at 1.8 Gy fractions, over the 5 weeks. Results: Thirty seven (94.8%) patients completed CCRT, and 2 patients removed during the treatment for toxicity issues. Of the 36 evaluable patients, 15 (41.7 %) patients achieved partial response, and 13 (36.1 %) had a stable disease with 77.8% of disease control rate. Among the 28 patients who had achieved disease control after CCRT, 8 patients (21.6 %) received gemcitabine-based post-CCRT chemotherapy without dose reduction or delay. With median 1.8 years of follow- up, the overall survival was 14.3 months (95% confidence interval [CI]; 10.6–17.9 months). Median progression free survival was 11.1 (95% CI 7.2–15.1) for all patients, and 7.9 months (95% CI 6.6–9.2) for those not received post-CCRT chemotherapy. No patient had grade 4 hematologic or non-hematologic toxicity. Eight patients (21.6%) had severe grade 3 toxicities, 7 (18.9%) with gastrointestinal toxicity and 1 (2.7%) with hematologic toxicity. Prognostic factors for survival were serum albumin (P=0.014; relative risk [RR], 3.4; 95% CI, 1.4, 8.6), and adjuvant gemcitabine treatment (P = 0.005; RR, 3.5; 95% CI, 1.2, 10.6). The prognostic grouping resulted in three groups with significantly different prognosis: group 1 (0 adverse factor; n=8; 1-year survival, 87.5%), group 2 (1 adverse factor; n=23; 1-year survival, 52.9%) and group 3 (2 adverse factors; n=8; 1-year survival, 25.0%). Conclusions: Combined therapy with capecitabine CCRT was well tolerated. Capecitabine seems to be a promising regimen in the treatment of LAPC, in terms of response, survival, and tolerable adverse effects.

No significant financial relationships to disclose.

Leptomeningeal carcinomatosis of gastric cancer: Multicenter retrospective analysis of 54 cases

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Background: Leptomeningeal carcinomatosis occurs in approximately 5% of patients with cancer. The most common cancers involving the leptomeninges are breast and lung cancer. However, gastric adenocarcinoma has been rarely reported with leptomeningeal carcinomatosis (LMC). Methods: We analyzed 54 cases of cytological confirmed gastric LMC at 4 institutions from 1994 to 2007. Results: Male to female ratio was 1.5:1. Median age of these patients was 49 years. The majority of patients had advanced disease at the initial diagnosis of gastric cancer. The clinical or pathologic TNM stages of the primary gastric cancer were IV in 38 patients (70%). The median interval from the diagnosis of the primary malignancy to the diagnosis of LMC was 6.3 months (range, 0 - 73.1 months). Of the initial endoscopic finding available 45 patients, Bormann type III and IV were 23 (51%) and 15 (33%) patients, respectively. Headache (85%) and nausea/vomiting (58%) were most common presenting symptoms of LMC. The intrathecal (IT) chemotherapy was administered to 36 patients - mainly with methotraxate alone (59%) or combination with ara- C/hydrocortisone (41%). Median IT treatment number was 7 (range, 1–18). Concomitant radiotherapy or chemotherapy was done in 25 patients and 10 patients, respectively. 17 patients (46%) were achieved cytological negative conversion. Median OS duration from diagnosis of LMC was 6.7 weeks (95% CI; 4.3–9.1 weeks). Clinically, initial advanced stage was predictive value of poor prognosis (P=0.009). But, Cytology negative conversion was predictive value of relatively longer survival duration (P=0.005). And, not only IT chemotherapy but also intravenous chemotherapy had been shown improvement of survival duration (P=0.010, P=0.005, respectively). Conclusions: Although gastric LMC has dismal prognosis, IT and IV chemotherapy could be help to extend survival duration of gastric LMC.

No significant financial relationships to disclose.

Phase III trial of adjuvant capecitabine/cisplatin (XP) versus capecitabine/cisplatin/RT (XPRT) in resected gastric cancer with D2 nodal dissection (ARTIST trial): Safety analysis

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Background: Although the adjuvant chemoradiation therapy has gained popularity and has become the standard of care in patients with resected gastric cancer in U.S., the role of chemoradiation therapy after extended D2 dissection has been questioned. We conducted a phase III trial to compare capecitabine/cisplatin (XP) vs XP + radiotherapy (RT) in curatively D2 resected gastric cancer patients in terms of disease free survival and overall survival. Methods: Eligibility criteria were as follows: stage Ib (T1N1, T2bN0) - IV (M1 excluded), curatively ≥ D2 resected gastric adenocarcinoma. XP only: X 2,000 mg/m2/d D1∼14, CDDP 60 mg/m2 D1 repeated every 3 weeks, 6 cycles; XP + RT: X 2,000 mg/m2/d D1∼14, CDDP 60 mg/m2 D1 x 2 cycles ⋄ RT 45 Gy (25 fractions) + X 1,650 mg/m2/d during RT ⋄ X 2,000 mg/m2/d D1∼14, CDDP 60 mg/m2 D1 x 2 cycles. The primary endpoint is 3-year disease-free survival. Results: From October 2004 to April 2008, 458 patients (XP arm: 228 patients; XP/RT arm: 230 patients) were enrolled. In XP arm, 172 (75%) of 228 enrolled patients completed 6 cycles of chemotherapy. In XP + RT arm, 188 (82%) of 230 patients completed the full course of XP 2 cycles - X + RT - XP 2 cycles. Conclusions: Safety and feasibility analysis of the two arms will be reported at the meeting.

No significant financial relationships to disclose.

A phase II study of imatinib mesylate as adjuvant treatment for curatively resected high-risk localized gastrointestinal stromal tumors

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Background: In our previous study, the presence of c-kit mutation as well as tumor size and mitotic count was an independent poor risk factor for relapse after curative resection of primary localized GIST. The patients with all the 3 poor risk factors had only 30% of 2 year relapse free survival rate (RFSR). (Kim, et al. Clin Cancer Res, 2004) It is also well known that c-kit exon 11 mutant GISTs respond better to imatinib treatment than the other mutant or wild type GISTs. Therefore, the patients who have primary localized GISTs with large size, high mitotic count, and c-kit exon 11 mutation may be the best candidate of adjuvant imatinib treatment. In this phase II study, we have evaluated the efficacy and safety of adjuvant imatinib for this patient group. Methods: Patients who underwent complete resection of a primary GIST with 1) c-kit exon 11 mutation, and 2) ≥10 mitoses/50 HPF, or tumor size ≥10 cm, or ≥5 mitoses/50 HPF and tumor size ≥5 cm were eligible. Patients received imatinib 400mg p.o. daily until recurrence of disease, intolerable toxicities, or for 2 years. The primary end point was relapse-free survival (RFS). Results: A total of 47 patients from 4 centers in Korea were enrolled. The median age was 57.0 years. Stomach was the most common primary site (n=31). Median primary tumor size was 7.5cm and median mitoses index was 12/50 HPF. With a median follow-up of 26.9 months, the median RFS and overall survival (OS) have not yet been reached. RFSR was 97.7% at 1-year and 92.7% at 2-years. Six relapses (12.8%) were documented among the 47 patients. The treatments were generally well tolerated. Grade 3–4 toxicities included neutropenia 27.7%, rash 8.5%, constipation 4.3%, anorexia 2.1%, vomiting 2.1%, and pruritis 2.1%. There were no episode of febrile neutropenia and treatment-related death. Conclusions: Postoperative adjuvant imatinib for 2 years were safe and could prolong the RFS in patients with high-risk of recurrence following complete surgical resection of the primary GIST. However, it remains unknown if this benefit in RFS can be translated into OS benefit. So, further follow-up is needed with comparison of OS with historical controls who could be use imatinib after recurrence.

[Table: see text]

The role of oophorectomy for colon cancer with ovarian metastasis

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Background: A recent study demonstrated that colorectal cancer with ovarian metastases were less responsive to chemotherapy compared to extraovarian metastases. Hence, the ovary may actually represent a “sanctuary” for metastatic cells from CRC. The aim of the study was to investigate the impact of oophorectomy on survival of colorectal cancer patients with ovarian metastasis. Methods: Between 1996 and 2008, 83 colorectal cancer patients underwent oophorectomy. For the historical control, 47 colorectal cancer patients without oophorectomy were included in the analysis. Survival and its associated factors were analyzed using Kaplan-Meier method, log-rank test and Cox-regression analysis. Results: The median age was younger (48 years) in the oophorectomy group when compared to the historical control (54 years) (P =.012). The proportion of synchronous metastasis was higher in the oophorectomy than the control group (57% vs 30%, respectively; P=.003). After a median follow-up duration of 60.8 months (range, 7.4 - 169.7 months), the median OS was significantly longer in the oophorectomy group (28.1 vs 21.2 months, oophorectomy vs non-oophoreectomy; P=.038). For ovary-specific survival (date of ovarian metastasis diagnosis to death), colorectal cancer patients with oophorectomy showed significantly favorable survival than the control group (20.8 vs 10.9 months, respectively; P<.001). At univariate analyses, no oophorectomy (P=.038), bilaterality of ovarian metastasis (P=0.032), the presence of extraovarian metastasis (P<0.001), elevated CEA (p<0.001), poor performance status (p=0.001), no palliative chemotherapy(p=0.001), no primary disease resection(p=0.005) were identified as significantly poor prognostic factors for overall survival. The no oophorectomy, no chemotherapy, extraovarian metastasis, elevated CEA, poor performance status retained statistical significance at multivariate level. (p=0.003, p=0.004, p=0.005, p=0.015, p=0.029, respectively). Conclusions: Based on this retrospective analysis, the oophorectomy significantly prolonged survival in colorectal cancer patients with ovarian metastases. A potential role of oophorectomy in the management of colorectal cancer should be prospectively studied.

No significant financial relationships to disclose.

Unusual Hall effect anomaly in MnSi under pressure

We report the observation of a highly unusual Hall current in the helical magnet MnSi in an applied pressure P=6-12 kbars. The Hall conductivity displays a distinctive stepwise field profile quite unlike any other Hall response observed in solids. We identify the origin of this Hall current with the effective real-space magnetic field due to chiral spin textures, which may be a precursor of the partial-order state at P>14.6 kbar. We discuss evidence favoring the chiral spin mechanism for the origin of the observed Hall anomaly.

An efficient rHSV-based complementation system for the production of multiple rAAV vector serotypes

Recombinant herpes simplex virus type 1 (rHSV)-assisted recombinant adeno-associated virus (rAAV) vector production provides a highly efficient and scalable method for manufacture of clinical grade rAAV vectors. Here, we present an rHSV co-infection system for rAAV production, which uses two ICP27-deficient rHSV constructs, one bearing the rep2 and cap (1, 2 or 9) genes of rAAV, and the second bearing an AAV2 ITR-gene of interest (GOI) cassette. The optimum rAAV production parameters were defined by producing rAAV2/GFP in HEK293 cells, yielding greater than 9000 infectious particles per cell with a 14:1 DNase resistance particle to infectious particle (DRP/ip) ratio. The optimized co-infection parameters were then used to generate large-scale stocks of rAAV1/AAT, which encode the human alpha-1-antitrypsin (hAAT) protein, and purified by column chromatography. The purified vector was extensively characterized by rAAV- and rHSV-specific assays and compared to transfection-made vector for in vivo efficacy in mice through intramuscular injection. The co-infection method was also used to produce rAAV9/AAT for comparison to rAAV1/AAT in vivo. Intramuscular administration of 1 x 10(11) DRP per animal of rHSV-produced rAAV1/AAT and rAAV9/AAT resulted in hAAT protein expression of 5.4 x 10(4) and 9.4 x 10(5) ng ml(-1) serum respectively, the latter being clinically relevant.

Stereoselective inhibition of cytochrome P450 forms by lansoprazole and omeprazolein vitro

The stereoselectivity of the inhibitory interaction potential of lansoprazole and omeprazole isomers on six human cytochrome P450 forms was evaluated using human liver microsomes. Lansoprazole enantiomers showed stereoselective inhibition of CYP2C9-catalysed tolbutamide 4-methylhydroxylation, CYP2C19-catalysed S-mephenytoin 4'-hydroxylation, CYP2D6-catalysed dextromethorphan O-demethylation, CYP2E1-catalysed chlorzoxazone 6-hydroxylation and CYP3A4-catalysed midazolam 1-hydroxylation, whereas omeprazole only inhibited CYP2C19 stereoselectively. Of the P450 forms tested, CYP2C19-catalysed S-mephenytoin 4'-hydroxylation was extensively inhibited by both the lansoprazole and omeprazole enantiomers in a competitive and stereoselective manner; the S-enantiomers of both drugs inhibited the hydroxylation more than the R-enantiomers. The estimated K(i) values determined for CYP2C19-catalysed S-mephenytoin 4'-hydroxylation were 0.6, 6.1, 3.4 and 5.7 microM for S-lansoprazole, R-lansoprazole, S-omeprazole and R-omeprazole, respectively. The results indicate that although both lansoprazole and omeprazole are strong inhibitors of CYP2C19, the inhibition of CYP2C19 by lansoprazole is highly stereoselective, whereas the inhibition by omeprazole is less stereoselective. In addition, S-lansoprazole, the most potent CYP2C19 inhibitor, is not a good CYP2C19-selective inhibitor owing to its inhibition of other P450 forms.

Dietary salt does not influence the disposition of verapamil enantiomers in relation to efflux transporter ABCB1 genetic polymorphism in healthy Korean subjects

To evaluate the effects of dietary salt on the stereoselective disposition of verapamil enantiomers in relation to the transporter ABCB1 2677GG/3435CC and 2677TT/3435TT haplotypes, ten healthy subjects were asked to take diets of three different salt levels for 7 days in a randomized, three-way crossover manner. The plasma concentrations of verapamil and norverapamil enantiomers were determined after a single oral dose of 240 mg verapamil on the last day of each phase. Pharmacokinetic parameters were calculated by non-compartmental analysis techniques and compared among the three different dietary salt phases. Compared with the medium salt diet, the high and low salt diets had no significant effect on the disposition of verapamil enantiomers. Moreover, the ABCB1 haplotypes did not alter the impact of dietary salt, although ABCB1 2677TT/3435TT subjects had slightly, but not significantly, higher C(max) and area under the curve (AUC) and lower T(max) for the verapamil enantiomers than did 2677GG/3435CC subjects in each salt phase.

Interlayer magnetoresistance of quasi-one-dimensional layered organic conductors

We studied the interlayer magnetoresistance of the representative quasi-one-dimensional (Q1D) layered organic conductor, (TMTSF)2PF6, over the full range of magnetic field orientations in three dimensions, and constructed a stereographic conductivity plot. Our results show that the previously reported angular-dependent magnetoresistance phenomena in Q1D conductors are closely related to one another in intermediate field orientations. Based on a comparison with theories, we can conclude that the Lebed resonance is the only fundamental effect and that other effects result from the modulation of the Lebed resonance amplitude. Most of the observed phenomena can be explained within the framework of the conventional Fermi liquid; however, the anomalous enhancement of the interlayer conductivity under a field parallel to the conducting planes suggests the existence of a new electron state.

Irinotecan monotherapy as second-line treatment in advanced pancreatic cancer

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Background: The aim of this phase II study was to determine whether second line therapy with single agent irinotecan could provide any clinical benefit in patients with gemcitabine- pretreated advanced pancreatic cancer. Methods: From January 2004 to October 2006, patients with advanced pancreatic cancer previously treated with gemcitabine alone or combination were treated with single agent irinotecan(150 mg/m2, biweekly), until unacceptable toxicity or disease progression. Primary endpoint was response rate with single stage design. Results: Twenty-eight patients were enrolled(22 male, 6 female, median age : 54.5 years (39–76)). Nine patients are still alive and 3 remain on therapy with stable disease. The median number of cycles was 3.5(1–12). Twenty-four patients were assessable for toxicity and 21 for response. The most common toxicities was diarrhea (grade 3, 12.5%). Grade 3 neutropenia in 1 patient was observed. Other hematological and non-hematological toxicities were mild and manageable. Partial responses were observed in 3 patients (3/21, 14%). An additional 9 patients (9/21, 43%) had stable disease as their best response. 12 patients have progressed with a median time-to-progression of 4.0 months. Conclusions: Single-agent irinotecan was tolerated with manageable toxicity, offering encouraging activity as second-line treatment of patients with advanced pancreatic cancer, refractory to gemcitabine.

No significant financial relationships to disclose.