Mitochondrial complex I activity in microglia sustains neuroinflammation

Sustained smouldering, or low-grade activation, of myeloid cells is a common hallmark of several chronic neurological diseases, including multiple sclerosis1. Distinct metabolic and mitochondrial features guide the activation and the diverse functional states of myeloid cells2. However, how these metabolic features act to perpetuate inflammation of the central nervous system is unclear. Here, using a multiomics approach, we identify a molecular signature that sustains the activation of microglia through mitochondrial complex I activity driving reverse electron transport and the production of reactive oxygen species. Mechanistically, blocking complex I in pro-inflammatory microglia protects the central nervous system against neurotoxic damage and improves functional outcomes in an animal disease model in vivo. Complex I activity in microglia is a potential therapeutic target to foster neuroprotection in chronic inflammatory disorders of the central nervous system3.

Mitochondrial reverse electron transport in myeloid cells perpetuates neuroinflammation

Sustained smouldering, or low grade, activation of myeloid cells is a common hallmark of several chronic neurological diseases, including multiple sclerosis (MS) 1 . Distinct metabolic and mitochondrial features guide the activation and the diverse functional states of myeloid cells 2 . However, how these metabolic features act to perpetuate neuroinflammation is currently unknown. Using a multiomics approach, we identified a new molecular signature that perpetuates the activation of myeloid cells through mitochondrial complex II (CII) and I (CI) activity driving reverse electron transport (RET) and the production of reactive oxygen species (ROS). Blocking RET in pro-inflammatory myeloid cells protected the central nervous system (CNS) against neurotoxic damage and improved functional outcomes in animal disease models in vivo . Our data show that RET in myeloid cells is a potential new therapeutic target to foster neuroprotection in smouldering inflammatory CNS disorders 3 .

The Prevalence and Management of Synchronous Prostate and Rectal Cancer

PURPOSE/OBJECTIVE(S)

Synchronous prostate and rectal cancer is rare and guidelines for co-management are not well established. This case series explores the prevalence of synchronous diagnosis and different treatment paradigms to propose a standardized approach to management.

MATERIALS/METHODS

We retrospectively reviewed all radiation treatments between 1/2017 and 12/2022 for curative intent treatment to both prostate and rectal cancer. Synchronous was defined as rectal or prostate cancer diagnosed within a 6-month period of each other. We collected baseline characteristics and treatment paradigms including the sequencing of chemoradiation (CRT), chemotherapy (CT), prostate boost, and surgery.

RESULTS

There were 10 out of 2204 total treated patients with prostate or rectal primary noted to have a synchronous diagnosis (0.45%). Table 1 shows characteristics and treatment approach for all patients with 50% receiving CRT and 50% CT alone first. At a median FU of 21.4 months, 2 patients did not complete therapy due to patient choice and both had progression of disease (POD). After completion of CRT, 6 patients underwent rectal surgery with 2 pathological complete response, and 2 patients proceeded with a Watch and Wait approach with clinical complete response on MRI. Prostate boost was delivered equally as often pre-surgery as post-surgery with both SBRT, EBRT and Seed Implant used. There was no grade 3+ RT related toxicity in the patients who completed all therapy.

CONCLUSION

This series represents one of the largest synchronous prostate and rectal cancer cohorts treated with curative intent. Future collaborative work is needed to develop guidelines in the treatment of synchronous prostate and rectal cancers. Although a rare diagnosis, the heterogeneity of approaches has led us to propose a standardized approach to management of synchronous diagnosis with upfront chemotherapy followed by EBRT inclusive of prostate and rectum followed by boost via brachytherapy (SBRT in non-candidates).

A Pilot Study of Durvalumab (MEDI4736) with Tremelimumab in Combination with Image-Guided Stereotactic Body Radiotherapy in the Treatment of Metastatic Anaplastic Thyroid Cancer

Background: Metastatic anaplastic thyroid cancer (ATC) has a poor prognosis. This pilot study aims to evaluate tremelimumab plus durvalumab with stereotactic body radiotherapy (SBRT) to improve overall survival (OS). Methods: Eligible patients received up to 4 doses tremelimumab (75 mg) given q4 weeks and up to 1 year of durvalumab (1500 mg) given q4 weeks. SBRT at 9 Gy × 3 fractions was given within the first 2 weeks of the start of treatment. Paired biopsies (pretreatment and between 3 and 10 weeks after the first dose of the drug treatment) were done in the medically qualified patients. Major inclusion criteria are metastatic ATC, Eastern Cooperative Oncology Group (ECOG) performance status 0-2, no prior immunotherapy, and last anticancer treatment >7 days before starting the study. The primary endpoint was 1 year OS with the combination of durvalumab, tremelimumab, and SBRT in metastatic ATC patients with a target of 1 year OS in ≥2 out of 12 patients. Results: A total of 13 patients signed consent but only 12 patients ultimately participated in this trial. One patient who consented to the protocol became ineligible for this study due to continued decline in performance status. Patient characteristics were as follows: male (n = 6) with a median age of 71 years (range: 49-82), and ECOG = 1. Nine patients had prior neck radiation and nine patients had prior chemotherapy. Next-generation sequencing and PD-L1 staining were done in the nine patients where tissue was available. High microsatellite instability (MSI) corresponding to mismatch repair defect was noted in two patients. There were zero confirmed responses and only one patient had stable disease and was treated with ≥4 cycles of study drugs. The median time that the patients were under treatment was 11 weeks (1-28 weeks). MSI status did not affect treatment response. High MSI patients were on treatment for 8-14 weeks before disease progression. The median OS was 14.5 weeks with only 1 patient alive beyond 1 year. The presence of a BRAF or p53 mutation did not appear to affect treatment outcome. Conclusions: Tremelimumab and durvalumab with SBRT did not improve OS for ATC. Future research is needed to examine other novel immunotherapy combinations with or without radiotherapy in the treatment of ATC. Clinical Trial Registration: NCT03122496.

Non-alcoholic fatty liver disease is a risk factor for occurrence of hepatocellular carcinoma after sustained virologic response in chronic hepatitis C patients: A prospective four-years follow-up study

Background and aim

The incidence of hepatocellular carcinoma (HCC) decreases significantly in chronic hepatitis C (CHC) patients with sustained virologic response (SVR) after pegylated-interferon plus ribavirin (PR) or direct-acting antiviral (DAAs) therapy. We follow-up a single cohort of CHC patients to identify risk factors associated with HCC development post-SVR.

Method

CHC patients with SVR in Beijing/Hong Kong were followed up at 12–24 weekly intervals with surveillance for HCC by ultrasonography and alpha-fetoprotein (AFP). Multivariate Cox proportional hazards regression analysis was used to explore factors associated with HCC occurrence.

Results

Between October 2015 and May 2017, SVR was observed in 519 and 817 CHC patients after DAAs and PR therapy respectively. After a median post -SVR follow-up of 48 months, HCC developed in 54 (4.4%) SVR subjects. By adjusted Cox analysis, older age (≥55 years) [HR 2.4, 95% CI (1.3–4.3)], non-alcoholic fatty liver diseases [HR 2.4, 95%CI (1.3–4.2), higher AFP level (≥20 ng/ml) [HR 3.4, 95%CI (2.0–5.8)], higher liver stiffness measurement (≥14.6 kPa) [HR 4.2, 95%CI (2.3–7.6)], diabetes mellitus [HR 4.2, 95%CI (2.4–7.4)] at pre-treatment were associated with HCC occurrence. HCC patients in the DAAs induced SVR group had a higher prevalence of NAFLD as compared with those in the PR induced SVR group, 62% (18/29) vs 28% (7/25), p = 0.026. A nomogram formulated with the above six independent variables had a Concordance-Index of 0.835 (95% CI 0.783–0.866).

Conclusion

Underlying NAFLD is associated with increased incidence of HCC in chronic HCV patients post-SVR, particularly in those treated with DAA.

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Patients with chronic hepatitis C infection are still at risk of HCC after achieving sustained virus clearance (SVR).

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Non-alcoholic liver disease (NAFLD) is emerging as an important risk factor for hepatocellular carcinoma.

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Underlying NAFLD is associated with increased incidence of HCC in patients with chronic HCV infection after sustained virologic response SVR.

An End-to-End Solution for Automatic Contouring of Tumor Region in Intraoperative Images of Breast Lumpectomy

Breast-conserving surgery, also known as lumpectomy, is an early stage breast cancer treatment that aims to spare as much healthy breast tissue as possible. A risk associated with lumpectomy is the presence of cancer positive margins post operation. Surgical navigation has been shown to reduce cancer positive margins but requires manual segmentation of the tumor intraoperatively. In this paper, we propose an end-to-end solution for automatic contouring of breast tumor from intraoperative ultrasound images using two convolutional neural network architectures, the U-Net and residual U-Net. The networks are trained on annotated intraoperative breast ultrasound images and evaluated on the quality of predicted segmentations. This work brings us one step closer to providing surgeons with an automated surgical navigation system that helps reduce cancer-positive margins during lumpectomy.

A-07 The Potential Impact of Nuclear History of Micronesia in Neuropsychological Functioning

Objective

As a result of 67 nuclear tests in the Marshall Islands between 1946 and 1958, inhabitants of Micronesia exposed to radiation exhibited chronic health issues and birth defects that persist to this day. This patient’s presentation may be an example of the continued residual impact of nuclear testing in Micronesia and demonstrates the importance of historical and biological factors when considering differential diagnoses.

Method

Patient is a six-year-old Micronesian male referred for assessment of psychological functioning. He was developmentally delayed since birth, exhibited unusual facial features, and previously diagnosed with Autism Spectrum Disorder (ASD). Presenting problems included speech delays, limited attention span, difficulty coping with challenges, narrow interests, impulsivity, difficulties interacting with peers, and toileting issues (i.e., defecating on the floor). Mother immigrated to Hawaii from Micronesia in 2006 and primarily speaks Chuukese. While pregnant, mother was on medications for diabetes, hospitalized with high blood pressure, and chewed tobacco daily. Patient experienced some difficulties during the neonatal period.

Results

Average nonverbal intelligence; moderately low receptive single word vocabulary; possible somatization, tendency to withdraw, and atypical behavior; problems with functional communication and daily living activities; and learning-related problems at school. Probability of autism within the Possibly/Very Likely range. Age-inappropriate projective drawings, with indications of potential genetic or developmental dysfunction.

Conclusions

Patient was diagnosed with ASD, with accompanying language impairment. Due to family history of radiation exposure in Micronesia and prenatal concerns, a rule out of other neurodevelopmental disorders and various genetic conditions were considered.

Pilot study combining PD-L1 antibody durvalumab (D) with CTLA-4 antibody tremelimumab (T) and stereotactic body radiotherapy (SBRT) to treat metastatic anaplastic thyroid cancer (ATC)

6088

Background: ATC is a rare and aggressive cancer with very limited treatment options. The thyroid is one of the most immunogenic organs in the body and PD-L1 is commonly expressed on ATC tumor cells and PD-1 in the inflammatory cells in the ATC microenvironment. However, antibodies to PD-1 as single agents have a poor record in this disease. Methods: This study evaluated the addition of T (75 mg every 4 weeks up to 4 doses) to D (1500 mg every 4 weeks). SBRT 9Gy x 3 fractions was given within the first 2 weeks of treatment to produce an “abscopal” effect. Major inclusion criteria: Metastatic ATC; ECOG PS 0-2; No prior immunotherapy; Last anti-cancer treatment > 7 days prior to starting study. Primary objective 1-year overall survival with target of ≥ 2 out of 12 patients. Results: 12 patients were accrued. Male – 50%; Median PS 1; Median Age – 71 (49-82); Prior radiation to neck (75%); Prior chemotherapy (75%). MSI-High was noted in 2/11 subjects. BRAFV600E mutation in 3/12 subjects. There were 0 confirmed responses and only 1 subject with SD for 4 cycles or longer. Median time on treatment was 11 weeks (1-28+ weeks). MSI status did not affect treatment response. MSI-High patients were on treatment before progression for 8-14 weeks. Median overall survival was 14.5 weeks with only one person alive past 1 year. Neither the presence of a BRAF or p53 mutation appeared to affect either outcome. Conclusions: T/D with SBRT was not active in metastatic ATC. Future studies looking at other novel immunotherapy combinations in ATC should be evaluated. Biopsies done on study are being analyzed. Clinical trial information: NCT03122496.

Detection of Early Human Papillomavirus-Associated Cancers by Liquid Biopsy

PURPOSE

A circulating tumor DNA (ctDNA) test to detect plasma Epstein-Barr viral DNA can be used to screen for early nasopharyngeal cancers; however, the reported sensitivity of viral ctDNA tests to detect human papillomavirus (HPV)-associated cancers is modest. We assessed the utility of droplet digital polymerase chain reaction (ddPCR) to detect early-stage HPV-associated cancers using sequential HPV16 and HPV33 assays that account for HPV subtype distribution and subtype sequence variants.

PATIENTS AND METHODS

We collected plasma specimens from 97 HPV-positive patients with oropharyngeal squamous cell carcinoma and eight patients with HPV-positive anal squamous cell carcinoma, each with locoregionally confined disease. Negative controls included samples from seven patients with HPV-negative head and neck cancers and 20 individuals without cancer.

RESULTS

Of 97 patients with nonmetastatic, locoregionally confined oropharyngeal squamous cell carcinoma, 90 patients had detectable HPV16 ctDNA and three patients had HPV33 ctDNA, indicating an overall sensitivity of 95.6%. Seven of eight patients with early anal cancer were HPV16 ctDNA positive. No HPV ctDNA was detected in 27 negative controls, indicating 100% specificity. HPV16 ctDNA was detected in 19 of 19 patients with low-volume disease, defined as patients with a single, asymptomatic positive lymph node (N1) or an isolated T1-2 asymptomatic primary tumor. HPV16 ctDNA levels directly corresponded to tumor responses to chemoradiation and surgery.

CONCLUSION

With an updated understanding of HPV subtypes and sequence variation, HPV ctDNA by ddPCR is highly sensitive and specific, identifying HPV16 and HPV33 subtypes in a similar distribution as reported in major genomic profiling studies. The detection of small tumors indicates that HPV16 and HPV33 ctDNA ddPCR could be readily used in early detection screening trials and in disease response monitoring, analogous to Epstein-Barr virus DNA.

Abstract PD4-10: 18F-fluoroestradiol (FES) and 18F-fluorodeoxyglucose (FDG) PET imaging in staging extent of disease in metastatic lobular breast cancer

Background: The histology and pattern of spread in lobular breast cancer has presented challenges in estimating extent of disease and identifying treatment options. 18F-FES is an estrogen analogue PET imaging tracer which measures tumor ER expression at multiple tumor sites simultaneously and predicts response to endocrine therapy. We analyzed FES-PET and FDG-PET SUV uptake in patients with metastatic lobular and ductal carcinoma to identify sites of tumor and responsiveness to therapy.

Methods: We retrospectively reviewed FES and FDG SUV uptake between ER+ lobular (n = 36) and ductal (n= 173, including 6 men) metastatic breast cancer patients enrolled in various institutional studies. Up to 3 lesions in each patient were evaluated by FES SUVmax and/or FDG SUVmax for a total of 475 lesions in FES images and 462 lesions in FDG images. Classification into three categories (low FDG, high FDG/high FES, and high FDG/low FES) was generated using recursive portioning with 5-fold internal cross validation. Using a Pearson Chi-squared test, we compared degree of uptake in FES and FDG between lobular and ductal carcinomas. We used linear mixed effects model to assess association of FES SULmean3 (Lean body mass adjusted SUV) and FDG SULmean3 with histology. Overall survival (OS), from time of FES-PET scan to death, and progression free survival (PFS) was evaluated between classification groups in both histologies using Kaplan-Meier curves and Cox model.

Results: In patients with metastatic breast cancer, 72 patients had low FDG, 96 had high FES/high FDG, and 41 with high FES/low FDG. Lobular lesions tended to have a higher proportion of patients in the risk group with lower FDG (42% vs 33%) and a lower proportion in the risk group with high FDG/low FES (11% vs 21%) but the difference was not statistically significant (p = 0.32). Mean (range) FES SULmean3 and FDG SULmax3 respectively for ductal was 1.38 (0.10, 6.7) and 3.17 (0.88, 12.26) and for lobular was 1.42 (0.34, 3.43) and 3.13 (1.04, 13.87). There was no significant difference between in FES SULmean3 and FDG SULmax3 between histologies. Following FES-PET imaging, patients with lobular carcinomas and low FDG demonstrated a higher median survival time (7.7 years) compared to high FDG/low FES (4.3 years) and high FDG/high FES (2.6 years). Similarly, patients with ductal carcinomas and low FDG had an improved median survival time (5.6 years) compared to both high FDG/high FES (2.9 years) and high FDG/low FES (2.5 years). However, the interaction between histology and the FDG/FES classifications was not significant (p = 0.86). Across a variety of tumor sites, lobular histology can be detected by both FES and FDG with no difference between the imaging modalities.

Conclusions: In the metastatic setting, quantitative FES and FDG can be used to discriminate indolent and aggressive phenotypes in both lobular and ductal breast cancer. A greater proportion of lobular carcinoma lesions had higher FES/lower FDG and would be anticipated to be more sensitive to endocrine therapy. Further prospective trials are needed to confirm the utility of FES to stage extent of disease in metastatic breast cancer.

Citation Format: Manohar PM, Peterson LM, Wu V, Jenkins IC, Novakova-Jiresova A, Specht JM, Link JM, Krohn KA, Kinahan PE, Mankoff DA, Linden HM. 18F-fluoroestradiol (FES) and 18F-fluorodeoxyglucose (FDG) PET imaging in staging extent of disease in metastatic lobular breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD4-10.

Hepatitis B reactivation in hepatitis B and C coinfected patients treated with antiviral agents: A systematic review and meta-analysis

There is an increased awareness of hepatitis B (HBV) reactivation in chronic hepatitis C (CHC) patients coinfected with HBV treated with pan-oral direct-acting antiviral agents (DAAs). We performed a systematic review and meta-analysis to compare the rate of HBV reactivation in CHC patients coinfected with overt HBV (hepatitis B surface antigen [HBsAg] positive) and occult HBV (HBsAg negative with positive HBV DNA) infection separately, treated with interferon (IFN)-based therapy to those with pan-oral DAAs. The primary outcome was HBV reactivation, and the secondary outcomes included hepatitis due to HBV reactivation, sustained virologic response (SVR) for CHC, loss of HBV DNA and HBsAg seroclearance. Although the pooled incidence rate of HBV reactivation, among CHC patients with overt HBV (n = 779), was similar among those treated with IFN-based therapy (14.5%, P < 0.001) and DAAs (12.2%, P = 0.03; P = 0.91 for heterogeneity between subgroups), it was reported to occur much earlier in those treated with DAAs (4-12 weeks during treatment) than in those treated with IFN-based therapies (most at the end of treatment and some during follow-up). Also, studies with DAA-based therapies were more likely to report incidence of hepatitis due to HBV reactivation (12.2% in DAAs vs. 0% in IFN; P = 0.009 for heterogeneity between subgroups). HBV reactivation and hepatitis due to HBV reactivation also occurred, though less frequently in CHC patients with occult HBV infection. CHC SVR was not affected by HBV reactivation (P = 0.27).

CONCLUSION

HBV reactivation occurs earlier and is clinically more significant in CHC patients coinfected with overt and occult HBV who are treated with pan-oral DAAs compared with IFN-based therapy. It is therefore important to have all patients screened for evidence of overt or occult HBV infection and managed during pan-oral DAAs therapy. (Hepatology 2017;66:13-26).

Hepatitis due to Reactivation of Hepatitis B Virus in Endemic Areas Among Patients With Hepatitis C Treated With Direct-acting Antiviral Agents

Hepatitis due to reactivation of hepatitis B virus (HBV) has been reported in patients treated with direct-acting antiviral (DAA) agents for chronic hepatitis C virus infection. We performed an observational study to determine the incidence of and factors associated with hepatitis in 327 patients receiving pan-oral DAA agents for HCV infections in areas endemic for HBV in China. Ten patients were positive for hepatitis B surface antigen (HBsAg), and 124 patients had occult HBV infection. HBV reactivation was determined by measuring HBV DNA and HBsAg status in serial serum samples collected every 2 weeks during DAA treatment and then every 4 weeks after treatment until week 12. In the total study population, 10 patients (3.1%) had hepatitis; 3 cases were associated with HBV reactivation (1 case not in the icteric phase, 1 case in the icteric phase, and 1 case with liver failure) and 7 from other causes. Testing positive for HBsAg before DAA treatment was a strong risk factor for developing hepatitis during treatment (hazard ratio, 15.0; P < .001).

Efficacy and safety of 3-week response-guided triple direct-acting antiviral therapy for chronic hepatitis C infection: a phase 2, open-label, proof-of-concept study

BACKGROUND

To shorten the course of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, we examined the antiviral efficacy and safety of 3 weeks of response-guided therapy with an NS3 protease inhibitor and dual NS5A inhibitor-NS5B nucleotide analogue.

METHODS

In this open-label, phase 2a, single centre study, Chinese patients with chronic HCV genotype 1b infection without cirrhosis were randomly allocated by a computer program to one of three treatment groups (sofosbuvir, ledipasvir, and asunaprevir; sofosbuvir, daclatasvir, and simeprevir; or sofosbuvir, daclatasvir, and asunaprevir) until six patients in each group (1:1:1) achieved an ultrarapid virological response (plasma HCV RNA <500 IU/mL by day 2, measured by COBAS TaqMan HCV test, version 2.0). Patients with an ultrarapid virological response received 3 weeks of therapy. Patients who did not achieve an ultrarapid response were switched to sofosbuvir and ledipasvir for either 8 weeks or 12 weeks. The primary endpoint was the proportion of patients with a sustained virological response at 12 weeks (SVR12) after treatment completion, analysed in the intention-to-treat population. All patients who achieved an ultrarapid virological response were included in the safety analysis. This trial is registered with ClinicalTrials.gov, number NCT02470858.

FINDINGS

Between April 5, 2015, and April 15, 2015, 26 eligible patients were recruited. 12 patients were assigned to sofosbuvir, ledipasvir, and asunaprevir; six to sofosbuvir, daclatasvir, and simeprevir; and eight to sofosbuvir, daclatasvir, and asunaprevir. Six patients in each group achieved an ultrarapid virological response (18 [69%]). All patients with an ultrarapid virological response who were given 3 weeks of triple therapy achieved SVR12. The most common adverse events were fatigue (one [17%] of six patients receiving sofosbuvir, ledipasvir, and asunaprevir; one [17%] of six patients receiving sofosbuvir, daclatasvir, and simeprevir; and two [33%] of six patients receiving sofosbuvir, daclatasvir, and asunaprevir) and headache (one [17%] patient in each group). No patients experienced any serious adverse events.

INTERPRETATION

In this proof-of-concept study, all patients with chronic HCV without cirrhosis who achieved an ultrarapid virological response on triple direct-acting antiviral regimens by day 2 and received 3 weeks of treatment were cured, with excellent tolerability. By shortening the duration of therapy from the currently recommended 12 weeks to 3 weeks, we could drastically reduce the cost of therapy and the rate of adverse events. Further large-scale studies should be done to confirm our findings.

FUNDING

Center for AIDS Research, National Institutes of Health, US Department of Energy, National Center for Research Resources and the Office of Research Infrastructure Programs, Cheng Si-Yuan (China-International) Hepatitis Research Foundation, and Humanity and Health Medical Group.

Twelve-week ribavirin-free direct-acting antivirals for treatment-experienced Chinese with HCV genotype 1b infection including cirrhotic patients

BACKGROUND

Treatment-experienced chronic hepatitis C (CHC) genotype (GT) 1b represents a major medical burden in China. We evaluate the efficacy, safety and cost-effectiveness of ribavirin (RBV)-free pan-oral direct-acting antivirals (DAAs) in treatment-experienced Chinese with GT1b CHC, including patients with cirrhosis.

METHODS

One hundred forty treatment-experienced GT1b CHC Chinese with and without cirrhosis were included in this study. Ninety-four patients were treated with either daclatasvir (DCV, 60 mg)-sofosbuvir (SOF, 400 mg) (group 1, n = 46) or ledipasvir (LDV, 90 mg)-SOF (400 mg) (group 2, n = 48) for 12 weeks. Forty-six patients treated with pegylated interferon and RBV therapy for 72 weeks were enrolled as the control group (group 3). Patients were followed at 4-weekly intervals till 24 weeks after the end of treatment.

RESULTS

All patients in group 1 (46/46, 100 %) and 2 (48/48, 100 %) had achieved sustained virologic response at 24 weeks after the end of treatment (SVR 24), which was significantly higher than that of group 3 (13/46, 28.3 %) (p < 0.001). The SVR 24 rates of cirrhotic patients in group 1 (27/27, 100 %) and 2 (27/27, 100 %) were also significantly higher than that of group 3 (3/25, 12 %) (p < 0.001). Twelve weeks of RBV-free LDV-SOF and DCV-SOF was either cost-saving or cost-effective. Adverse events were significantly lower in group 1 and 2 compared with group 3 (p < 0.001).

CONCLUSION

Compared with standard therapies, 12 weeks of RBV-free DAA therapies is highly effective, well tolerated and cost-effective in treatment-experienced Chinese with GT1b CHC including patients with cirrhosis.

Will Sofosbuvir/Ledipasvir (Harvoni) Be Cost-Effective and Affordable for Chinese Patients Infected with Hepatitis C Virus? An Economic Analysis Using Real-World Data

BACKGROUND

Little is known on the cost-effectiveness of novel regimens for hepatitis C virus (HCV) compared with standard-of-care with pegylated interferon (pegIFN) and ribavirin (RBV) therapy in developing countries. We evaluated cost-effectiveness of sofosbuvir/ledipasvir for 12 weeks compared with a 48-week pegIFN-RBV regimen in Chinese patients with genotype 1b HCV infection by economic regions.

METHODS

A decision analytic Markov model was developed to estimate quality-adjusted-life-years, lifetime cost of HCV infection and incremental cost-effectiveness ratios (ICERs). SVR rates and direct medical costs were obtained from real-world data. Parameter uncertainty was assessed by one-way and probabilistic sensitivity analyses. Threshold analysis was conducted to estimate the price which can make the regimen cost-effective and affordable.

RESULTS

Sofosbuvir/ledipasvir was cost-effective in treatment-experienced patients with an ICER of US$21,612. It varied by economic regions. The probability of cost-effectiveness was 18% and 47% for treatment-naive and experienced patients, and it ranged from 15% in treatment-naïve patients in Central-China to 64% in treatment-experienced patients in Eastern-China. The price of 12-week sofosbuvir/ledipasvir treatment needs to be reduced by at least 81% to US$18,185 to make the regimen cost-effective in all patients at WTP of one time GDP per capita. The price has to be US$105 to make the regimen affordable in average patients in China.

CONCLUSION

Sofosbuvir/ledipasvir regimen is not cost-effective in most Chinese patients with genotype 1b HCV infection. The results vary by economic regions. Drug price of sofosbuvir/ledipasvir needs to be substantially reduced when entering the market in China to ensure the widest accessibility.

Colibactin biosynthesis and biological activity depend on the rare aminomalonyl polyketide precursor

The as-yet unidentified E. coli metabolite colibactin induces DNA damage in eukaryotic cells and promotes tumorigenesis. Its wide distribution in pathogenic and probiotic strains has raised great interest in its structure and biosynthesis. Here we show that colibactin formation involves a rare aminomalonyl unit used as a building block.

The organization of colposcopy services in Ontario: recommended framework

OBJECTIVE

The purpose of this guideline is to help ensure the provision of high-quality colposcopy practices in the province of Ontario, including those conducted as diagnostic procedures in follow-up to an abnormal cervical screening test.

METHODS

This document updates the recommendations published in the 2008 colposcopy guideline from Cancer Care Ontario, The Optimum Organization for the Delivery of Colposcopy Service in Ontario. A systematic review of guidelines was conducted to evaluate the existing evidence and recommendations concerning these key aspects of colposcopy: □ Training, qualification, accreditation, and maintenance of competence□ Practice setting requirements□ Operational practice□ Quality indicators and outcomes.

RESULTS

This guideline provides recommendations on training and maintenance of competence for colposcopists in the practice settings in which colposcopic evaluation and treatments are conducted. It also provides recommendations on operational issues and quality indicators for colposcopy.

CONCLUSIONS

This updated guideline is intended to support quality improvement for colposcopy for all indications, including the follow-up of an abnormal cervical screening test and work-up for lower genital tract lesions that are not clearly malignant. The recommendations contained in this document are intended for clinicians and institutions performing colposcopy in Ontario, and for policymakers and program planners involved in the delivery of colposcopy services.

Biomarkers in transplantation: Prospective, blinded measurement of predictive value for the flow cytometry crossmatch after negative antiglobulin crossmatch in kidney transplantation

This prospective, blinded observational study was conducted to measure the predictive value the of flow cytometric crossmatch for biopsy-proven acute rejection, graft loss, or death following kidney transplantation. Patients were selected for renal transplantation on the basis of a conventional antihuman globulin cytotoxic T-cell crossmatch. Flow crossmatch was performed simultaneously, but the results were not disclosed to the transplant team. A total of 257 kidney transplant recipients were enrolled in the study; 78 patients experienced biopsy-proven rejection in the first post-transplant year, and 41 patients lost their graft or died during the period of follow-up (mean: 2046 days). Kaplan-Meier estimates of rejection, graft loss, or patient death did not differ between subjects with a positive or negative flow crossmatch. Cox analyses showed no influence of the flow crossmatch on the risk of biopsy-proven acute rejection (P = 0.987). The sensitivity and specificity of the flow crossmatch for prediction of biopsy-proven rejection were 0.128 and 0.883, and the positive and negative post-test probabilities were 0.323 and 0.301, respectively. The magnitude of the channel shift did not influence the multivariate Cox regression model. The area under the receiver operating characteristic curve of the flow crossmatch was 0.483 (P = 0.71) and 0.572 (P = 0.38), respectively for the living and cadaver transplant recipients, indicating no discriminative value in this study population. Flow crossmatch appears to have no significant incremental value in predicting biopsy-proven acute rejection, graft loss, or death following kidney transplantation in patients who have a negative antihuman globulin cytotoxic T-cell crossmatch against their donor.

CRF2 receptor activation prevents colorectal distension induced visceral pain and spinal ERK1/2 phosphorylation in rats

BACKGROUND AND AIMS

Activation of corticotropin releasing factor 1 (CRF1) receptors is involved in stress related responses and visceral pain, while activation of CRF2 receptors dampens the endocrine and some behavioural stress responses. We hypothesised that CRF2 receptor activation may influence visceral pain induced by colorectal distension (CRD) in conscious rats, and assessed the possible sites and mechanisms of action.

METHODS

Male Sprague-Dawley rats were exposed to CRDs (60 mm Hg, 10 minutes twice, with a 10 minute rest interval). Visceromotor responses (VMR) were measured by electromyography or visual observation. Spinal (L6-S1) extracellular signal regulated kinase 1/2 (ERK 1/2) activation following in vivo CRD and CRF2 receptor gene expression in the T13-S1 dorsal root ganglia (DRG) and spinal cord were determined. Inferior splanchnic afferent (ISA) activity to CRD (0.4 ml, 20 seconds) was assessed by electrophysiological recording in an in vitro ISA nerve-inferior mesenteric artery (intra-arterial)-colorectal preparation.

RESULTS

In controls, VMR to the second CRD was mean 31 (SEM 4)% higher than that of the first (p<0.05). The selective CRF2 agonist, human urocortin 2 (hUcn 2, at 10 and 20 microg/kg), injected intravenous after the first distension, prevented sensitisation and reduced the second response by 8 (1)% and 30 (5)% (p<0.05) compared with the first response, respectively. RT-PCR detected CRF2 receptor gene expression in the DRG and spinal cord. CRD (60 mm Hg for 10 minutes) induced phosphorylation of ERK 1/2 in neurones of lumbosacral laminae I and IIo and the response was dampened by intravenous hUcn 2. CRD, in vitro, induced robust ISA spike activity that was dose dependently blunted by hUcn 2 (1-3 microg, intra-arterially). The CRF2 receptor antagonist, astressin2-B (200 microg/kg subcutaneously or 20 microg intra-arterially) blocked the hUcn 2 inhibitory effects in vivo and in vitro.

CONCLUSIONS

Peripheral injection of hUcn 2 blunts CRD induced visceral pain, colonic afferent, and spinal L6-S1 ERK 1/2 activity through CRF2 receptor activation in rats.

Determination of polymorphic forms of ranitidine–HCl by DRIFTS and XRPD

The identification, characterization and quantification of crystal forms are becoming increasingly important within the pharmaceutical industry. A combination of different physical analytical techniques is usually necessary for this task. In this work solid-state techniques, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and X-ray powder diffractometry (XRPD) were combined to analyze polymorphic purity of crystalline ranitidine-HCl, an antiulcer drug, H2 receptor antagonists. A series of 12 different mixtures of Form 1 and 2 was prepared by geometric mixing and their DRIFT spectra and XRD powder patterns were obtained and analyzed, either alone or combined together, using Artificial Neural Networks (ANNs). A standard feed-forward network, with back-propagation rule and with multi layer perceptron architecture (MPL) was chosen. A working range of 1.0-100% (w/w) of crystal Form 2 in Form 1 was established with a minimum quantifiable level (MQL) of 5.2% and limit of detection of 1.5% (w/w). The results demonstrate that DRIFTS combined with XRPD may be successfully used to distinguish between the ranitidine-HCl polymorphs and to quantify the composition of binary mixtures of the two.

Alloimmunization and erythrocyte autoimmunization in transfusion-dependent thalassemia patients of predominantly asian descent

The development of hemolytic alloantibodies and erythrocyte autoantibodies complicates transfusion therapy in thalassemia patients. The frequency, causes, and prevention of this phenomena among 64 transfused thalassemia patients (75% Asian) were evaluated. The effect of red blood cell (RBC) phenotypic differences between donors (mostly white) and Asian recipients on the frequency of alloimmunization was determined. Additional transfusion and patient immune factors were examined. 14 (22%) of 64 patients (75% Asian) became alloimmunized. A mismatched RBC phenotype between the white population, comprising the majority of the donor pool, and that of the Asian recipients, was found for K, c, S, and Fyb antigens, which accounts for 38% of the alloantibodies among Asian patients. Patients who had a splenectomy had a higher rate of alloimmunization than patients who did not have a splenectomy (36% vs 12.8%; P =.06). Erythrocyte autoantibodies, as determined by a positive Coombs test, developed in 25% or 16 of the 64 patients, thereby causing severe hemolytic anemia in 3 of 16 patients. Of these 16, 11 antibodies were typed immunoglobulin G [IgG], and 5 were typed IgM. Autoimmunization was associated with alloimmunization and with the absence of spleen (44% and 56%, respectively). Transfused RBCs had abnormal deformability profiles, more prominent in the patients without a spleen, which possibly stimulated antibody production. Transfusion of phenotypically matched blood for the Rh and Kell (leukodepleted in 92%) systems compared to blood phenotypically matched for the standard ABO-D system (leukodepleted in 60%) proved to be effective in preventing alloimmunization (2.8% vs 33%; P =.0005). Alloimmunization and autoimmunization are common, serious complications in Asian thalassemia patients, who are affected by donor-recipient RBC antigen mismatch and immunological factors.

Stability of polymorphic forms of ranitidine hydrochloride

Ranitidine-HCl can exist in two different polymorphic forms: form I (m.p. 134-140 degrees C) and form II (m.p. 140-144 degrees C). In the present study the stability of form I of ranitidine-HCl to a selection of powder pretreatments, to reflect conditions which might occur in manufacturing procedures, and also to a limited range of storage conditions was investigated. The original samples of form I and form II used were characterised by X-ray powder diffraction (XRPD), hot stage microscopy (HSM) and differential scanning calorimetry (DSC). A quantitative XRPD method for determining the fraction of form II in the presence of form I was used. XRPD data were analysed using regression techniques and artificial neural networks (ANN). The quantitative XRPD technique was then used to monitor the relative proportion of form II in each treated sample. Pretreatments of form I included (i) mixing with form II or with common excipients (ii) compression and grinding (iii) contact with solvents (followed by drying) before storage. Storage conditions involved three temperatures (20 degrees C, 30 degrees C, 42 degrees C) and three relative humidities (45% RH; 55% RH; 75% RH). Samples were stored for a period of 6 months. A limited factorial design was used. No increase in the form II:form I ratio was observed in the following pretreatment processes: introduction of form II nuclei into form I; introduction of excipients to form I; compression of form I powder at 5 and 15 tons; normal mixing and grinding processes; addition of isopropanol (IPA) or water/IPA mix followed by drying. In the pretreatment process where water was added to form I powder (with most or all of the powder dissolving), drying of the liquefied mass led to a mix of form I and form II. On storage at room temperature (20-30 degrees C), low relative humidity (45-55% RH), and in an air-tight container there was no increase in the form II:form I ratio. Storage of form I/form II mixes, particularly at high humidity, resulted in a preferential loss of form II (compared to form I). Loss was greater at 30 degrees C/75% RH than at 20 degrees C/75% RH. Form II was also preferentially lost under low humidity conditions created by a saturated solution of potassium carbonate (45% RH) at the elevated temperature of 42 degrees C. This environment was shown to be acidic.

Ranitidine hydrochloride X-ray assay using a neural network

A simple X-ray powder diffractometric (XRD) method with artificial neural networks (ANNs) for data modelling was developed to recognize and quantify two crystal modifications of ranitidine HCl in mixtures and thus, provide information about the solid state of the bulk drug. The method was also used to quantify ranitidine HCl from tablets in the presence of other components. An ANN consisting of three layers of neurons was trained by using a back-propagation learning rule. A sigmoid output function was used in the hidden layer to facilitate non-linear fitting. Unlike other techniques the ANN method described here employed pattern recognition on the entire XRD pattern. Correct classification was mainly influenced by the XRD pattern resolution. It was shown that data transformations improved the quantitative performance when the XRD patterns were not contaminated by other components. Only smoothed X-ray diffractograms were required to distinguish between the two crystalline forms in a mixture. In the case of ranitidine-HCl quantification from tablets, where significant interference with tablet excipients was present, better results were obtained without data transformations. The trained ANN perfectly quantified ranitidine HCI polymorphic forms from mixtures (mean sum of squared error was less than 0.02%) and ranitidine HCl form 1 from tablets (recovery = 98.65). Excellent quantification performance of the ANN analysis. demonstrated in this study, serves as an indication of the broad potential of neural networks in pattern analysis. While the system described has been developed to interpret XRD patterns, peak detection has implications in every chemical application where the recognition of peak-shaped signals in analytical data is important.

Somatostatin receptor subtype 2A expression in the rat retina

Somatostatin is mainly expressed by sparsely occurring amacrine and interplexiform cells in the retina. In this study, we characterized the expression and cellular localization of one of the somatostatin subtype (sst) receptors, sst2A, in the rat retina. The presence of sst2A receptor messenger RNA in retinal extracts was demonstrated by reverse transcription-polymerase chain reaction using specific primers to detect the sst2 receptor and its isoforms, sst2A and sst2B. Specific sst2A receptor immunoreactivity was mainly localized to the plasma membrane of several neuronal cell types. In the outer retina, immunoreactivity was localized to cone photoreceptors, horizontal cells, and rod and cone bipolar cells. Double-label experiments showed the co-localization of sst2A receptor and protein kinase C (alpha and beta), a rod bipolar cell marker, and of sst2A receptor and Calbindin-D28k, a horizontal cell marker. In the inner retina, sst2A receptor immunoreactivity occurred in tyrosine hydroxylase-positive amacrine cells; most were of medium to large size. These findings indicate that somatostatin may act at a distance, in a paracrine manner, on several cell types that express the sst2A receptor, and therefore exert a broad modulatory influence on both scotopic and photopic visual pathways.

Powder diffractometric assay of two polymorphic forms of ranitidine hydrochloride

A simple X-ray powder diffractometric method was developed for the qualitative and quantitative assay of the two crystalline modifications of ranitidine-HCl. The main purpose of the present work was to investigate if artificial neural networks (ANNs) could be applied in quantitative X-ray diffractometric analyses. The ANN approach was compared with a conventional mixture design method. The results obtained by the ANN had a smaller standard deviation and relative error and a better precision at lower concentrations. ANNs provide a simple alternative to conventional statistical modelling methods to identify the non-linear relationship without complex equations.

Generation of an adenovirus vector lacking E1, e2a, E3, and all of E4 except open reading frame 3

Toxicity and immunity associated with adenovirus backbone gene expression is an important hurdle to overcome for successful gene therapy. Recent efforts to improve adenovirus vectors for in vivo use have focused on the sequential deletion of essential early genes. Adenovirus vectors have been constructed with the E1 gene deleted and with this deletion in combination with an E2a, E2b, or E4 deletion. We report here a novel vector (Av4orf3nBg) lacking E1, E2a, and all of E4 except open reading frame 3 (ORF3) and expressing a beta-galactosidase reporter gene. This vector was generated by transfection of a plasmid carrying the full-length vector sequence into A30.S8 cells that express E1 and E2a but not E4. Production was subsequently performed in an E1-, E2a-, and E4-complementing cell line. We demonstrated with C57BL/6 mice that the Av4orf3nBg vector effected gene transfer with an efficiency comparable to that of the Av3nBg (wild-type E4) vector but that the former exhibited a higher level of beta-galactosidase expression. This observation suggests that E4 ORF3 alone is able to enhance RNA levels from the beta-galactosidase gene when the Rous sarcoma virus promoter is used to drive transgene expression in the mouse liver. In addition, we observed less liver toxicity in mice injected with the Av4orf3nBg vector than those injected with the Av3nBg vector at a comparable DNA copy number per cell. This study suggests that the additional deletion of E4 in an E1 and E2a deletion background may be beneficial in decreasing immunogenicity and improving safety and toxicity profiles, as well as increasing transgene capacity and expression for liver-directed gene therapy.

GABAergic regulation of lordosis: influence of gonadal hormones on turnover of GABA and interaction of GABA with 5-HT

The role of GABAergic neurons in activating female sexual behavior and possible mechanisms for GABAergic effects on behavior were examined in female rats. First, effects of the ovarian hormones estrogen and progesterone (P), at doses which promote lordosis, on levels and turnover/activity of GABA, were examined in brain areas which regulate lordosis. Utilizing AOAA, an inhibitor of GABA degradation, the accumulation rate of GABA (turnover/activity) was assessed in ovariectomized (Ovx), Ovx + estrogen and Ovx + estrogen + P-treated rats. Estradiol increased GABA accumulation rates in the arcuate-median eminence and in the area dorsal to and surrounding the VMN (VMN-S). P administration following estrogen priming enhanced GABA turnover in the medial preoptic area (mPOA) and further increased turnover in the VMN-S while GABA turnover decreased in the dorsomedial nucleus. No effects of hormones were noted in the VMN itself or in the dorsal midbrain central gray. Reverse dialysis of the GABAA antagonist bicuculline into the basomedial hypothalamus was associated with a time-dependent inhibition of lordosis and a 300% increase in 5-HT release in the basomedial hypothalamus as measured by in vivo dialysis. These results provide additional evidence that GABAergic neurons mediate the physiological regulation of female sexual behavior and suggest that such mediation may involve an interaction with 5-HT containing neurons.

Induction of mammary carcinomas by N-methyl-N-nitrosourea in ovariectomized rats treated with epidermal growth factor

The importance of epidermal growth factor (EGF) in both normal and malignant mammary gland development are presented in these studies. Initial findings demonstrated that in the absence of ovarian hormones, EGF had a significant proliferative effect on mammary epithelial cells. To determine whether mammary epithelial cells grown with EGF, in the absence of ovarian hormones, could be transformed by N-methyl-N-nitrosourea (MNU), female ovariectomized Lewis rats were implanted with pellets containing EGF for 1 week and then treated with MNU for initiation. Two days after MNU treatment, ovaries were implanted and EGF pellets were removed from all ovariectomized groups in order to promote carcinogenesis. The mammary carcinoma incidence of the EGF-stimulated group (90%) was not significantly different from the intact group (100%). The mammary cancer morphology of EGF-treated carcinomas was either ductal carcinoma or cribriform adenocarcinoma, whereas intact animals developed mainly papillary and occasional cribriform carcinomas. Fifty-eight percent of the carcinomas from the EGF group were ovarian hormone-independent compared with 10% of carcinomas from the intact group. These results demonstrate that EGF-induced proliferation during initiation with MNU was sufficient to induce the transformation of mammary carcinomas in the absence of ovarian hormones. The hormonal dependency of these EGF-induced carcinomas were different compared with MNU-initiated mammary carcinomas in intact rats.