31Phosphorus magnetic resonance spectroscopy of the liver for evaluating inflammation and fibrosis in autoimmune hepatitis.

BACKGROUND: Liver biopsy is the gold standard in evaluating inflammation and fibrosis in autoimmune hepatitis. AIMS: In search of non-invasive follow-up tools in autoimmune hepatitis, we evaluated 31phosphorus magnetic resonance spectroscopy (31P MRS). METHODS: Twelve consecutive AIH patients (mean age 42.8 years, 10 women) underwent liver biopsy, routine laboratory liver function tests, which were compared to findings in 31P MRS and transient elastography (TE). RESULTS: Phosphoenolpuryvate (PEP) correlated with the grade of inflammation (r = 0.746, p = .005) and thromboplastin time (r = 0.592, p = .043). It also differentiated patients with active inflammation from patients without (t = 3.781, p = .009). There was no correlation between PEP and aminotransferase or immunoglobulin G levels. The phosphoethanolamine (PE)/phosphocholine (PC) ratio, PE/glyserophosphoethanolamine (GPE) ratio and PC/[total phosphomonoester (PME) + phosphodiester (PDE)] ratios correlated with immunoglobulin G (r = 0.764, p = .006; r = 0.618, p = .043; and r= -0.636, p = .035, respectively). PME/PDE and PE/GPE correlated with fibrosis (r = 0.668, p = .018 and r = 0.604, p = .037). PE/GPE also differentiated F3 from F0-2 patients (t = 3.810, p = .003). Phosphorus metabolites did not correlate with TE results and TE did not correlate with liver histology or laboratory parameters. CONCLUSIONS: 31P MRS seems to detect active inflammation and advanced fibrosis in AIH patients. TE was ineffective in fibrosis quantification.

Short interferon and ribavirin treatment for HCV genotype 2 or 3 infection: NORDynamIC trial and real-life experience.

OBJECTIVE: Interferon-free therapy for hepatitis C virus (HCV) infection is costly, and therefore patients with advanced fibrosis are prioritized. Although coupled with considerable side effects, a large proportion of genotype 2/3 infected patients achieve a sustained virological response (SVR) following interferon-based therapy. The present study evaluates experimental clinical trial and verifying real-life data with the aim of identifying patients with a high likelihood of favorable outcome following short interferon-based treatment. MATERIAL AND METHODS: The impact of established response predictors, e.g. age, ITPA and IL28B genetic variants, IP-10, liver histopathology and early viral kinetics on outcome was evaluated among HCV genotype 2/3 infected patients enrolled in the NORDynamIC trial. Similarly outcome was evaluated among Finnish and Swedish real-life genotype 2/3 infected patients treated for 12-16 weeks in accordance with national guidelines. RESULTS: In the NORDynamIC trial, age < 40 years or achieving HCV RNA < 1000 IU/mL day 7 were highly predictive of favorable outcome following 12 weeks therapy. Among 255 Finnish real-life patients below the age of 40 years treated for 12 weeks with interferon and ribavirin, 87% of HCV genotype 2 and 79% of genotype 3 infected patients achieved SVR, and among 117 Swedish real-life patients treated for 12-16 weeks, 97% of HCV genotype 2 and 94% of genotype 3 infected achieved SVR. CONCLUSIONS: Short interferon-based therapy offers a high likelihood of achieving SVR for selected HCV genotype 2/3 infected patients, and is an acceptable option given that a thorough discussion of the side effects is provided prior to initiation.

Malignancies in inflammatory bowel disease.

Patients with inflammatory bowel diseases (IBDs) are at increased risk of colorectal cancer (CRC), but the risk varies between different studies and seems to be decreasing. The cumulative risk of CRC has been reported to be 1%, 2%, and 5% after 10, 20, and over 20 years of disease duration, respectively, in recent meta-analysis. Disease duration and grade of inflammation are the main driving forces of dysplasia and CRC development. Also, the risk of extraintestinal cancers is increased in IBD, where the degree of immunosuppression and its duration are the most important risk factors. Most important extraintestinal malignancies are lymphomas and non-melanoma skin cancers, both of which are increased in patients receiving thiopurines. Also, extraintestinal manifestations or concomitant diseases such as primary sclerosing cholangitis predispose IBD patients to malignancies such as cholangiocarcinoma. History of previous cancer increases the risk of developing either new or recurrent cancers and should be taken into account when choosing therapy and planning surveillance. Dysplasia and cancer screening and surveillance must be individualized according to patients' risk factors. Malignancies are the second most common cause of death after cardiovascular diseases in both genders in patients with IBD.

Inflammation and disease duration have a cumulative effect on the risk of dysplasia and carcinoma in IBD: a case-control observational study based on registry data.

Patients with long-standing inflammatory bowel disease (IBD) have an increased risk for colorectal carcinoma (CRC). Earlier studies suggest that the severity of inflammation is an independent risk factor for CRC in ulcerative colitis (UC). We investigated the role of histological inflammation as a risk factor for colorectal dysplasia or CRC to better target dysplasia surveillance in IBD. By combining our hospital patient registry and pathology database between 1996 and 2008, we identified 183 IBD patients with dysplasia or CRC. The control group was collected from our registry of IBD patients. Histological severe inflammation was present in 41.4% of patients with dysplasia and in 24.1% of patients with CRC, but in only 4.3% of controls. Severe inflammation had an odds ratio (OR) of 31.8 [95% confidence interval (CI): 15.6-64.9] for dysplasia or carcinoma compared to patients with no inflammation. Among patients with mild to moderate inflammation, the OR was 2.6 (95% CI: 1.6-4.1). Disease duration increased the annual risk for dysplasia or CRC by 4.5%. Coexisting primary sclerosing cholangitis (PSC) did not elevate the risk, whereas use of thiopurines (OR = 0.09, 95% CI: 0.02-0.33) and also 5-aminosalicylic acid (OR 0.17, 95% CI: 0.017-1.01) protected against CRC. As conclusion, degree of inflammation and duration of disease cumulatively increase the risk for dysplasia and CRC. PSC was not identified as a risk factor. We demonstrated that use of thiopurines strongly protects against CRC. These results can be applied to better target dysplasia surveillance in IBD patients.

Mucosal healing at 3 months predicts long-term endoscopic remission in anti-TNF-treated luminal Crohn's disease.

BACKGROUND AND AIMS: Studies performed on patient and disease characteristics predicting the treatment response in tumor necrosis factor alpha antibody (anti-TNF)-treated Crohn's disease (CD) have generally been based on clinical data. Only a few studies have assessed the role of endoscopy as a predictor for long-term response for anti-TNF therapy. Our aim was to evaluate the role of early endoscopy in predicting the long-term endoscopic response to anti-TNF in active luminal CD in a clinical setting. PATIENTS AND METHODS: Forty-two patients with active luminal CD, treated for at least 3 months with anti-TNF, either adalimumab (52%) or infliximab (48%), were included in this prospective study. Data on the simple endoscopic score for Crohn's disease (SES-CD) at 3 months after therapy commencement, and either data on the SES-CD or surgery after 1 year, were available for all patients. Endoscopic remission was defined as SES-CD 0-2. RESULTS: At 3 months after commencing anti-TNF therapy, 10 patients (24%) were in endoscopic remission. Thirty-three patients continued anti-TNF as maintenance therapy. At 1 year, endoscopic remission (11/33, 33%) was significantly more common in those patients who had been in endoscopic remission at 3 months, compared with those with endoscopically active disease at 3 months (7/10, 70% vs. 4/23, 17%, p = 0.01). The 3-month SES-CD had a sensitivity of 88%, and specificity of 64%, to predict 1-year endoscopic remission in patients who received anti-TNF maintenance therapy. CONCLUSIONS: In anti-TNF-treated active luminal CD mucosal healing at 3 months is a strong predictor for long-term endoscopic response.

Surrogate markers and clinical indices, alone or combined, as indicators for endoscopic remission in anti-TNF-treated luminal Crohn's disease.

OBJECTIVE: Endoscopically confirmed mucosal healing has become an important therapeutic goal in the treatment of Crohn's disease (CD). The role of clinical indices, such as the Crohn's disease activity index (CDAI) and the Harvey-Bradshaw index (HBI), and surrogate markers, such as C-reactive protein (CRP) and fecal calprotectin, to indicate remission determined by endoscopy needs to be clarified. We analyzed the role of surrogate markers and clinical indices, separately and in combination, by comparing them with endoscopically scored disease activity in biologically treated CD patients. MATERIAL AND METHODS: Prospectively collected data of all patients with inflammatory bowel disease treated with tumor necrosis factor alpha antibodies in a tertiary center between 2007 and 2010. Altogether 210 endoscopies in 64 CD patients were analyzed. The simple endoscopic score for Crohn's disease (SES-CD) was used for scoring disease activity and compared with available data on concurrent CDAI, HBI, CRP, and calprotectin. RESULTS: Endoscopic activity demonstrated a stronger correlation with calprotectin and CRP than with the clinical indices. Neither the clinical indices nor CRP was reliable at identifying endoscopic remission. However, calprotectin alone identified endoscopic remission with a sensitivity of 84% and specificity of 74%, but was beaten, although not statistically significantly, by a combined index, based on calprotectin and the HBI. CONCLUSIONS: Clinical scores commonly used in the assessment of disease activity are unreliable at differentiating endoscopic remission from active CD. Despite this, a score based on a combination of fecal calprotectin and the HBI is a new promising tool for identifying endoscopic remission.

Human herpesvirus 6 and cytomegalovirus in ileocolonic mucosa in inflammatory bowel disease.

OBJECTIVES: Reactivation of a latent cytomegalovirus (CMV) may occur in inflammatory bowel disease (IBD). Data of human herpesvirus 6 (HHV-6)--a close relative to CMV--in active IBD are scarce. The aim of this study was to detect HHV-6 and CMV antigens in the mucosa of active and inactive IBD. MATERIAL AND METHODS: 79 IBD patients (47 ulcerative colitis (UC) and 32 Crohn's disease (CD)) were recruited and endoscopic and histological disease activity was scored. Control group consisted of 15 non-IBD patients with normal colonoscopy. Immunohistochemical stainings for HHV-6B and CMV antigens were performed on biopsy specimens from the ileum and colorectum. The intensity of HHV-6B and CMV expression was graded as negative, mild, moderate, or intense. RESULTS: HHV-6B antigen was positive in 35 (44%) and CMV in 64 (81%). Of controls, 6 (40%) were mildly positive for HHV-6 and 6 (40%) for CMV. In IBD, both CMV and HHV-6B intensity correlated with endoscopic disease severity (CMV p = 0.010 and HHV-6 p = 0.048). Simultaneous HHV-6B and CMV antigen expression occurred in 29 (37%) and associated with endoscopic activity (p = 0.006) and to a number of immunosuppressives (p = 0.033). A significant difference in HHV-6B positivity was found between endoscopically active and inactive UC (p = 0.040). Both CMV and HHV-6B intensity correlated with histological severity in the rectal biopsy specimens (for CMV p = 0.040 and for HHV-6B p = 0.027). CONCLUSIONS: Both viruses occurred ubiquitously in the IBD mucosa. Coexistence of viruses was common and associated with disease activity and use of immunosuppressives. HHV-6B intensity correlated with endoscopic severity in UC.

Esophageal morbidity and function in adults with repaired esophageal atresia with tracheoesophageal fistula: a population-based long-term follow-up.

OBJECTIVE: We assessed esophageal morbidity and relationships between surgical complications, symptoms, endoscopic findings, immunohistochemistry, and esophageal motility in adults with repaired esophageal atresia (EA). SUMMARY OF BACKGROUND DATA: There exist no previous population-based long-term follow-up studies on EA. METHODS: Participants were interviewed, and they underwent esophageal endoscopy and manometry. Matched control subjects (n = 287) served as controls. RESULTS: A total of 101 (42%) individuals representative of the entire study population participated at a mean age of 36 years (range, 21-57). Symptomatic gastroesophageal reflux had occurred in 34% and dysphagia in 85% of the patients and in 8% and 2% of the controls (P < 0.001 for both). Endoscopic findings included hiatal hernia (28%), Barrett's esophagus (11%), esophagitis (8%), and anastomotic stricture (8%). Immunohistochemistry revealed esophagitis in 25%, and CDX2-positive columnar epithelial metaplasia in 21%, with additional goblet cells and MUC2 positivity in 6%. Gastroesophageal reflux and dysphagia were equally common in individuals with normal histology, esophagitis, or epithelial metaplasia. Manometry demonstrated nonpropagating peristalsis in 80% of the patients, and low distal wave amplitudes of the esophagus in all the changes being significantly worse in those with epithelial metaplasia (P < or = 0.022 metaplasia vs. esophagitis/normal). Anastomotic complications (odds ratio [OR]: 8.6-24, 95% confidence interval [CI]: 1.7-260, P = 0.011-0.008), age (OR: 20, 95% CI: 1.3-310, P = 0.034), low distal esophageal body pressure (OR: 2.6, 95% CI: 0.7-10, P = 0.002), and defective esophageal peristalsis (OR: 2.2, 95% CI: 0.4-11, P = 0.014) predicted development of epithelial metaplasia. CONCLUSIONS: Significant esophageal morbidity associated with EA extends into adulthood. Surgical complications, increasing age, and impaired esophageal motility predict development of epithelial metaplasia after repair of EA.

Objectively assessed disease activity and drug persistence during ustekinumab treatment in a nationwide real-world Crohn's disease cohort.

OBJECTIVE: Long-term evidence on ustekinumab treatment response and persistence in patients with Crohn's disease in a real-world setting is scarce. We performed a retrospective nationwide chart review study of long-term clinical outcomes in Crohn's disease patients treated with ustekinumab. METHODS: The study was conducted in 17 Finnish hospitals and included adult Crohn's disease patients who received an initial intravenous dose of ustekinumab during 2017-2018. Disease activity data were collected at baseline, 16 weeks, and 1 year from health records. RESULTS: The study included 155 patients. The disease was stricturing or penetrating in 69 and 59% had prior Crohn's disease-related surgeries, and 97% had a treatment history of at least one biologic agent. Of 93 patients with ≥1 year of follow-up, 77 (83%) were still on ustekinumab at 1 year. In patients with data available, from baseline to the 1-year follow-up the simple endoscopic score for Crohn's disease (SES-CD) decreased from 10 to 3 (P = 0.033), C-reactive protein from 7 to 5 mg/L, (P < 0.001) and faecal calprotectin from 776 to 305 µg/g (P < 0.001). CONCLUSIONS: Ustekinumab treatment in patients with highly refractory Crohn's disease resulted in high long-term treatment persistence and significantly reduced disease activity, assessed with objective markers for intestinal inflammatory activity.

Effect of steatosis and inflammation on liver fibrosis in chronic hepatitis C.

BACKGROUND/AIMS: The role of liver biopsy has been questioned in the management of patients with hepatitis C viral (HCV) infection. The aims of this study were to determine the impact of clinical parameters and degree of inflammation and steatosis on liver fibrosis. PATIENTS/METHODS: Clinical data and liver histology findings in 510 HCV patients were analysed. RESULTS: Hepatitis C virus genotype 1 (GT-1) was found in 38%, GT-2 in 15% and GT-3 in 45% of patients. In liver biopsy specimens, inflammation activity was present in 68%, increased fibrosis in 19% and marked steatosis in 17% of patients. Independent clinical risk factors for the increased fibrosis were patients' age at biopsy, body mass index (BMI) and duration of HCV. Steatosis and inflammation activity were independent histological risk factors for fibrosis only in GT-1; in GT-3, only inflammation correlated independently with fibrosis. CONCLUSIONS: Age at liver biopsy, BMI and duration of HCV were independent risk factors for increased fibrosis in HCV patients. Steatosis as a risk factor for fibrosis is evident in GT-1. When scoring liver biopsies of HCV patients, the degree of steatosis should be included in addition to fibrosis and inflammation activity.

Metabolic profile of liver damage in non-cirrhotic virus C and autoimmune hepatitis: A proton decoupled 31P-MRS study.

PURPOSE: To study liver 31P MRS, histology, transient elastography, and liver function tests in patients with virus C hepatitis (HCV) or autoimmune hepatitis (AIH) to test the hypothesis that 31P MR metabolic profile of these diseases differ. MATERIALS AND METHODS: 25 patients with HCV (n=12) or AIH (n=13) underwent proton decoupled 31P MRS spectroscopy performed on a 3.0T MR imager. Intensities of phosphomonoesters (PME) of phosphoethanolamine (PE) and phosphocholine (PC), phosphodiesters (PDE) of glycerophosphoethanolamine (GPE) and glycerophosphocholine (GPC), and γ, α and ß resonances of adenosine triphosphate (ATP), and nicotinamide adenine dinucleotide phosphate (NADPH) were determined. Liver stiffness was measured by transient elastography. Inflammation and fibrosis were staged according to METAVIR from biopsy samples. Activities of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALT) and thromboplastin time (TT) were determined from serum samples. RESULTS: PME had a stronger correlation with AST (z=1.73, p=0.04) and ALT (z=1.77, p=0.04) in HCV than in AIH patients. PME, PME/PDE, PE/GPE correlated positively and PDE negatively with inflammatory activity. PE, PC and PME correlated positively with liver function tests. CONCLUSION: 31P-MRS suggests a more serious liver damage in HCV than in AIH with similar histopathological findings. 31P-MRS is more sensitive in detecting inflammation than fibrosis in the liver.

Increased Oxidative Stress in the Proximal Stomach of Patients with Barrett's Esophagus and Adenocarcinoma of the Esophagus and Esophagogastric Junction.

OBJECTIVES: Oxidative stress (OS) is an essential element in the pathogenesis of Barrett's esophagus (BE) and its transformation to adenocarcinoma (EAC). The state of OS in the proximal stomach of patients with BE and EAC is unknown. Isoprostanes are a specific marker of OS not previously used to determine OS from BE/EAC tissue samples. PATIENTS AND METHODS: OS was measured in 42 patients with BE (n = 9), EAC (n = 9), or both (n = 24) and 15 control patients. A STAT-8-Isoprostane EIA Kit served to identify 8-Isoprostanes (8-IP), and a Glutathione Assay Kit was used to measure glutathione reduced form (GSH) and glutathione oxidized form. An OxiSelect Oxidative DNA Damage ELISA Kit (8-OHdG) served to measure 8-OH-deoxyguanosine. RESULTS: The 8-IP (P = .039) and 8-OHdG (P = .008) levels were higher, and the GSH level lower (P = .031), in the proximal stomach of the study group than in that of the controls. Helicobacter pylori infection was present in 8% of the study patients. CONCLUSIONS: In the proximal stomach of BE and EAC patients, OS was elevated and antioxidative capacity was reduced. This finding suggests that the gastroesophageal reflux causing BE also induces oxidative stress in the proximal stomach and may contribute to the development of cancer in the proximal stomach and gastric cardia.

Does fecal calprotectin predict short-term relapse after stopping TNFα-blocking agents in inflammatory bowel disease patients in deep remission?

BACKGROUND AND AIMS: This prospective multicenter study examined whether elevated fecal calprotec tin (FC) concentrations after stopping TNFα-blocking therapy can predict clinical or endoscopic relapse. In addition, we evaluated the impact of histological remission on the relapse risk. METHODS: We enrolled inflammatory bowel disease (IBD) patients who were in clinical, endoscopic, and FC-based (< 100 µg/g) remission after a minimum 11 months of TNFα-blocking therapy. The patients were followed-up for 12 months after the discontinuation of TNFα-blocking therapy. FC was collected monthly for the first 6 months and thereafter every second month. Ileocolonoscopy was performed at inclusion, at 4 months, at the study end, and at the time of clinical relapse. RESULTS: Of 52 enrolled patients, 49 (16 Crohn's disease, 33 ulcerative colitis/IBD unclassified) provided the stool samples requested and comprised the study group. During the follow-up, 15/49 (31%) relapsed, whereas 34 (69%) remained in remission. Patients relapsing showed constantly elevated FC levels for a median of 94 (13-317) days before the relapse. Significant increase in median FC levels was seen 2 (p = 0.0014), 4 (p = 0.0056), and 6 (p = 0.0029) months before endoscopic relapse. Constantly normal FC concentrations during the follow-up were highly predictive for clinical and endoscopic remission. Normal FC concentrations in patients with remission were associated with histological remission. CONCLUSION: FC seems to increase and remain elevated before clinical or endoscopic relapse, suggesting that it can be used as a surrogate marker for predicting and identifying patients requiring close follow-up in clinical practice.

Outcome after discontinuation of TNFα-blocking therapy in patients with inflammatory bowel disease in deep remission.

BACKGROUND: Few data are available on the disease course in patients with inflammatory bowel disease (IBD) in deep remission after discontinuing tumor necrosis factor α (TNFα)-blocking therapy. In this prospective multicenter study, we evaluated the relapse rate, predictive factors, and the response to retreatment after discontinuation of TNFα-blocking therapy in patients with IBD in deep remission. METHODS: We recruited 52 patients (17 Crohn's disease, 30 ulcerative colitis, and 5 IBD unclassified) in clinical, endoscopic, and fecal calprotectin-based (<100 µg/g) remission after at least 1 year of TNFα-blocking therapy. Clinical and endoscopic remission and relapse were defined according to validated indices. After discontinuation of therapy, the patients were followed up with endoscopic assessment at 4 and 12 months. In the event of a clinical relapse with endoscopically active disease or minor clinical symptoms but severe endoscopic relapse, TNFα-blocking therapy was restarted. RESULTS: After a median follow-up time of 13 (range, 12-15) months, 17/51 (33%) patients relapsed (5/17 Crohn's disease, 12/34 ulcerative colitis/IBD unclassified, 1 patient lost to follow-up at 6 mo). Ten experienced clinical and endoscopic relapse, 5 clinical relapse with mild endoscopic activity, and 2 severe endoscopic relapse. No specific predictive factors were associated with the relapse. Retreatment was effective in 94% of patients. CONCLUSIONS: After cessation of TNFα-blocking therapy in patients with IBD in deep remission, up to 67% remained in clinical remission during the 12-month follow-up. Importantly, 85% of these patients sustained endoscopic remission. The response to restart of TNFα antagonists was effective and well tolerated.

Increasing incidence of inflammatory bowel diseases between 2000 and 2007: a nationwide register study in Finland.

BACKGROUND: The incidence of inflammatory bowel disease (IBD) is high in Western countries, but during the last decade the figures have stabilized, or only slightly increased; at the same time, an increasing incidence rate has been observed in Eastern Europe and Asia. The purpose of this study was to estimate the incidence of IBD in Finland between 2000 and 2007. METHODS: New IBD cases between 2000-2007 were retrieved from the national database of special reimbursements for drugs costs. The register includes virtually all Finnish IBD patients since 1986. The incidence rates were calculated per 100,000 persons assuming a Poisson distribution. RESULTS: In total, 14,214 IBD patients were identified; 10,352 had ulcerative colitis (UC) and 3,862 had Crohn's disease (CD). During the whole study period the mean annual incidence of IBD per 100,000 was 34.0: in CD 9.2 and in UC 24.8. The incidence of UC was notably higher in males (27.8) than in females (21.9). In CD the incidence rates did not differ significantly between genders. The incidence of UC increased from 22.1 in 2000-2001 to 27.4 in 2006-2007. The incidence of CD increased only slightly. CONCLUSION: In Finland, the incidence of IBD is high, and UC is almost three times more common than CD. During the new millennium the incidence rate of UC has increased, while the incidence rate of CD has remained fairly stable. To the best of our knowledge, the incidence of UC in this nationwide register study is one of the highest reported to date.

Endoscopic monitoring of infliximab therapy in Crohn's disease.

BACKGROUND: So far, infliximab (IFX) therapy for the treatment of Crohn's disease (CD) has generally been guided by clinical symptoms. Data on treatment response as ascertained by endoscopy in IFX therapy are scarce. The aims of this study were to measure the endoscopic response rate during IFX induction and maintenance therapy in luminal CD, and also evaluate the role of endoscopy in monitoring IFX therapy. METHODS: Data obtained from 71 patients with active luminal CD and treated with IFX were analyzed retrospectively. The endoscopy findings were scored according to mucosal activity as: 0 (remission), 1-2 (mild), 3-4 (moderate), and 5-6 (severe). A positive endoscopic response was determined by a decrease in score of at least two points and mucosal healing was assigned a score of between 0-2. RESULTS: At baseline all patients presented with moderate or severe luminal inflammation. A positive endoscopic response occurred in 73% of patients at 3 months and when IFX was continued, the endoscopic response was maintained in 77% of these patients at 12 months. Mucosal healing at first follow-up endoscopy was documented in 45% of patients and was highly predictive for its persistence at 12 months, maintained in 90% of patients, when IFX was continued. CONCLUSIONS: Endoscopy at 3 months from the start of IFX therapy helps to predict responders to IFX for maintenance therapy in active luminal CD.