Relationships between Changes in Muscle Shear Modulus, Urinary Titin N- Terminal Fragment, and Maximum Voluntary Contraction Torque after Eccentric Exercise of the Elbow Flexors

The study aimed to investigate the relationships between the shear modulus of the biceps brachii (BB) and brachialis muscle (BA) and the total of the two (BB+BA), and urinary titin N-terminal fragment (UTF), maximum voluntary isometric contraction (MVC), and other indirect markers. Fifteen healthy men performed five sets of 10 eccentric contractions using a dumbbell corresponding to 50% of MVC at 90° measured at baseline. The elbow joint of the left arm was extended from 90° to 180° (180° = full extension) in 5 s in the exercise, and was returned with support from the examiner to prevent concentric contraction. Shear modulus of BB and BA were measured by ultrasound shear wave elastography, and UTF, MVC, and range of motion of the elbow joint (ROM) were recorded before; immediately after; and 1, 24, 48, 72, 96, and 168 h after the exercise. After calculating the shear modulus of BB and BA, two values were added (BB+BA). The shear modulus peaked at 48 h, UTF peaked at 96 h, MVC and ROM changed largest at immediately, and muscle soreness peaked at 48 h post-exercise. Significant (p < 0.05) relationships were found between changes in BB shear modulus and BA shear modulus (r = 0.874), BB+BA shear modulus (r = 0.977), UTF (r = 0.681), and MVC (r = -0.538). Significant (p < 0.05) relationships were also observed between changes in BA shear modulus and BB+BA shear modulus (r = 0.957), UTF (r = 0.682), MVC (r = -0.522), and ROM (r = -0.600). Moreover, significant (p < 0.05) relationships were observed between changes in BB+BA shear modulus and UTF (r = 0.703), MVC (r = -0.549), and ROM (r = -0.547). These results indicate that shear modulus of each muscle (i.e., BB and BA) provide more precise information about muscle damage than UTF, MVC and ROM.

Adrenocortical hypoperfusion detected by contrast-enhanced ultrasound in a dog with trilostane-induced hypoadrenocorticism

A 12-year-old neutered male Chihuahua dog was diagnosed with pituitary-dependent hypercortisolism and treated with trilostane. Eighty-nine days later, the dog showed lethargy accompanied by hyponatraemia and hyperkalaemia. Hypoadrenocorticism due to trilostane was suspected, but the result of the adrenocorticotropic hormone stimulation test was not conclusive. Contrast-enhanced ultrasound showed loss of adrenocortical blood flow in both adrenal glands, indicating adrenocortical hypoperfusion and isolated hypoadrenocorticism. Treatment with fludrocortisone acetate improved the condition and electrolyte abnormalities. Thirteen months later, the dog showed alopecia, and an adrenocorticotropic hormone stimulation test revealed increased cortisol concentration, indicating hypercortisolism recurrence. The dog died due to progressive deterioration 22 months after the initial presentation. Post-mortem examination revealed focally extensive necrosis with marked calcification in the parenchyma of the adrenal glands and regeneration of the cells in the zona fasciculata with severe fibrosis. Adrenocortical hypoperfusion detected by contrast-enhanced ultrasound can support the diagnosis of adrenal necrosis and hypoadrenocorticism.

Changes in Muscle Shear Modulus and Urinary Titin N-Terminal Fragment after Eccentric Exercise

This study aimed to investigate the relationship between the muscle shear modulus of the biceps brachii, urinary titin N-terminal fragment (UTF), and other damage markers after eccentric exercise. Seventeen healthy males performed five sets of ten eccentric exercises with dumbbells weighing 50% of the maximum voluntary contraction (MVC) at the elbow joint. Muscle shear modulus with range of interest set to only biceps brachii muscle measured by ultrasound shear wave elastography, UTF, MVC, range of motion (ROM), and soreness (SOR) were recorded before, immediately after, and 1, 24, 48, 72, 96, and 168 h after eccentric exercise. Each marker changed in a time course pattern, as found in previous studies. The peak shear modulus showed a moderate negative correlation with peak MVC (r = -0.531, P < 0.05) and a strong positive correlation with peak UTF (r = 0.707, P < 0.01). Our study results revealed a significant relationship between muscle strength, shear modulus measured by ultrasound SWE, and titin measured by UTF, as a non-invasive damage marker after eccentric exercise to track changes in EIMD.

Reduction of respiratory motion artifacts in gadoxetate-enhanced MR with a deep learning-based filter using convolutional neural network

Objectives

To reveal the utility of motion artifact reduction with convolutional neural network (MARC) in gadoxetate disodium–enhanced multi-arterial phase MRI of the liver.

Methods

This retrospective study included 192 patients (131 men, 68.7 ± 10.3 years) receiving gadoxetate disodium–enhanced liver MRI in 2017. Datasets were submitted to a newly developed filter (MARC), consisting of 7 convolutional layers, and trained on 14,190 cropped images generated from abdominal MR images. Motion artifact for training was simulated by adding periodic k-space domain noise to the images. Original and filtered images of pre-contrast and 6 arterial phases (7 image sets per patient resulting in 1344 sets in total) were evaluated regarding motion artifacts on a 4-point scale. Lesion conspicuity in original and filtered images was ranked by side-by-side comparison.

Results

Of the 1344 original image sets, motion artifact score was 2 in 597, 3 in 165, and 4 in 54 sets. MARC significantly improved image quality over all phases showing an average motion artifact score of 1.97 ± 0.72 compared to 2.53 ± 0.71 in original MR images (p < 0.001). MARC improved motion scores from 2 to 1 in 177/596 (29.65%), from 3 to 2 in 119/165 (72.12%), and from 4 to 3 in 34/54 sets (62.96%). Lesion conspicuity was significantly improved (p < 0.001) without removing anatomical details.

Conclusions

Motion artifacts and lesion conspicuity of gadoxetate disodium–enhanced arterial phase liver MRI were significantly improved by the MARC filter, especially in cases with substantial artifacts. This method can be of high clinical value in subjects with failing breath-hold in the scan.

Key Points

• This study presents a newly developed deep learning–based filter for artifact reduction using convolutional neural network (motion artifact reduction with convolutional neural network, MARC).

• MARC significantly improved MR image quality after gadoxetate disodium administration by reducing motion artifacts, especially in cases with severely degraded images.

• Postprocessing with MARC led to better lesion conspicuity without removing anatomical details.

Epidemiology of massive hepatocellular carcinoma in dogs: A 4-year retrospective study

Hepatocellular carcinoma (HCC) is the most common primary liver tumour in dogs. However, the clinical features and risk factors of HCC have not been confirmed. The objective of this study was to investigate the clinical features and risk factors for canine HCC. Medical records of 44 dogs diagnosed with HCC at Hokkaido University Veterinary Teaching Hospital between 2013 and 2017 were retrospectively reviewed. All dogs evaluated at the teaching hospital during the study period were used as the reference population for breed, age, sex predispositions or possible related factors for HCC, including concurrent disorders. Clinical characteristics of HCC were determined using propensity score matching analysis. The prevalence of HCC diagnosis was 0.96%. Multivariate analysis revealed that dogs diagnosed with HCC were significantly older (odds ratio [OR], 1.20; 95% confidence intervals [CI], 1.07-1.33) than the reference population. Welsh Corgis (OR, 3.68; 95% CI, 1.56-8.67) and Beagles (OR, 4.33; 95% CI, 1.58-11.90) were significantly predisposed to HCC. Twenty-seven of 44 dogs with HCC had at least one concurrent disorder. The most common concurrent disorder was hyperadrenocorticism (n = 10), and the adjusted odds of hyperadrenocorticism in dogs with HCC were 4.13 higher than those of the reference population (95% CI, 1.95-8.76). Propensity score matching analysis revealed that thrombocytosis (n = 30/43), increased alanine aminotransferase (n = 41/44), increased alkaline phosphatase (n = 42/44), and hypercalcemia (n = 13/32) were significantly associated with HCC diagnosis. The results of this study suggest that Welsh Corgis and Beagles are breeds with a predisposition for HCC and that hyperadrenocorticism might be a potential risk factor.

Optically active distorted cyclic triptycenes: chiral stationary phases for HPLC

A pair of optically active triptycene derivatives ((R,R)- and (S,S)-8) with a distorted cyclic structure were synthesized via an intramolecular etherification and evaluated as a novel chiral selector for high-performance liquid chromatography. The (R,R)- and (S,S)-8-based chiral stationary phases (CSPs) were found to be particularly effective in the resolution of axially chiral biaryl compounds. The importance of the distorted cyclic structure present in 8 for chiral recognition was demonstrated by comparisons with the corresponding non-cyclic model compound ((R,R)-9), which did not display enantioselectivity in the separation of the test racemates.

We have succeeded in developing triptycene-based chiral stationary phases with a distorted cyclic structure, which can resolve a series of axially chiral compounds.

Genetic variation and local differences in Pacific cod Gadus macrocephalus around Japan

The population structure of the Pacific cod Gadus macrocephalus was examined using 15 microsatellite loci and mitochondrial DNA (ND2 region). In total, 274 individuals were sampled from 16 locations around Japan to estimate the level of genetic differentiation and effective population size (N_e ). Pairwise F_ST , analysis of molecular variance and Bayesian clustering analysis suggested the presence of two genetically distinct groups in waters around Japan, with a higher N_e value in the eastern group than in the western group. A possible factor that restricts gene flow between groups may be related to the water temperature differences in the south-western part of the Sea of Japan, where the Tsushima Warm Current flows around the area inhabited by the western group, which may limit migration between the west and east.

Comparison of Survival Times for Dogs with Pituitary-Dependent Hyperadrenocorticism in a Primary-Care Hospital: Treated with Trilostane versus Untreated

Background

Although pituitary‐dependent hyperadrenocorticism (PDH) is one of the most common endocrinopathies in dogs, the effects of withholding treatment on survival time in dogs with PDH remain unclear.

Hypothesis/Objectives

The purpose of this study was to clarify the effects of treatment in dogs with PDH by comparing survival times between dogs treated with trilostane and untreated dogs.

Animals

Forty‐three dogs diagnosed with PDH at a primary‐care hospital in Japan between June 2009 and January 2014.

Methods

Retrospective cohort study. The medical records of dogs with PDH treated with trilostane (n = 17) or left untreated (n = 26) were reviewed retrospectively. Survival analysis at 2 years after diagnosis of PDH was performed.

Results

Median survival time for the trilostane group was not reached (95% confidence interval [CI], 443 days–not applicable) and was significantly longer than the 506 days (95% CI, 292–564 days; P = .016) for the untreated group. Multivariate Cox proportional hazards analysis (including age at diagnosis, basal cortisol concentration at diagnosis, and treatment group) only identified assignment to the untreated group (hazard ratio, 5.01; 95% CI, 1.63–15.44) as associated with increased mortality.

Conclusions and Clinical Importance

The results of this retrospective cohort study suggest that withholding treatment for dogs with PDH might be associated with a higher risk of death. This represents the largest study to date to report survival times of untreated dogs with PDH.

Clinical Utility of Diagnostic Laboratory Tests in Dogs with Acute Pancreatitis: A Retrospective Investigation in a Primary Care Hospital

BACKGROUND

Acute pancreatitis (AP) occurs frequently in dogs, but most previous studies examining the diagnosis of AP have used data from secondary care hospitals.

HYPOTHESIS/OBJECTIVES

The aim of this study was to investigate the clinical utility of diagnostic laboratory tests in dogs with AP in a primary care hospital.

ANIMALS

Sixty-four dogs with clinical signs suggestive of AP diagnosed with nonpancreatic disease (NP) or AP.

METHODS

Medical records were retrospectively reviewed, including diagnostic laboratory tests considered potentially useful in the diagnosis of AP. The diagnostic accuracy of amylase and FUJI DRI-CHEM lipase (FDC lip) were investigated using receiver operating characteristics (ROC). In addition, we verified whether diagnostic laboratory tests were useful for evaluating duration of hospitalization and as biomarkers for monitoring recovery.

RESULTS

Activities of amylase and FDC lip were significantly higher in the AP group than in the NP group (P = .001, P < .001, respectively). The sensitivity of FDP lip activity for diagnosing AP was 100% (95% confidence interval [CI], 87.7-100%); the specificity was 89.5% (95% CI, 66.9-98.7%). Area under the ROC curve for FDC lip activity was 0.98 (95% CI, 0.93-1). High alanine aminotransferase (ALT) activity was associated with extended duration of hospitalization (P = .04). A significant difference in C-reactive protein (CRP) concentration before and 5 days after treatment was found (P = .001).

CONCLUSIONS AND CLINICAL IMPORTANCE

Measurement of FDC lip activity appears useful for diagnosing AP. High ALT activity might be associated with prolonged duration of hospitalization, and CRP might be useful as a biomarker for monitoring recovery from AP.

Natural history of bleeding risk in colonic diverticulosis patients: a long-term colonoscopy-based cohort study

BACKGROUND

The natural history of bleeding risk from colonic diverticulosis remains unclear.

AIM

To identify the incidence of bleeding in colonic diverticulosis patients and associated risk factors.

METHODS

A cohort of 1514 patients with colonoscopy-confirmed asymptomatic diverticulosis was selected between 2001 and 2013. Age, sex and location of colonic diverticulosis (right or left side, or bilateral) were assessed. The endpoint was a bleeding event, and data were censored at the time of last colonoscopy. The cumulative and overall incidences of bleeding were estimated using the Kaplan-Meier and person-years methods. The Cox proportional hazards model was used to estimate age- and sex-adjusted hazard ratios (aHRs).

RESULTS

The median follow-up period was 46 months. Bleeding events occurred in 35 patients, and the median time-to-event interval was 50 months. Kaplan-Meier analysis showed that the cumulative incidence of diverticular bleeding was 0.21% at 12 months, 2.2% at 60 months and 9.5% at 120 months. By the person-years method, the overall incidence rate of bleeding was 0.46 per 1000 patient-years. On multivariate analysis, age ≥70 (aHR. 3.7) and bilateral diverticulosis (aHR, 2.4) were significant risk factors for bleeding.

CONCLUSIONS

This long-term follow-up study demonstrated that the cumulative incidence of bleeding from diverticulosis was approximately 2% at 5 years and 10% at 10 years, and the overall incidence was 0.46 per 1000 patient-years. Bilateral diverticulosis increased the risk of bleeding.

FOLFIRI plus bevacizumab as second-line therapy in patients with metastatic colorectal cancer after first-line bevacizumab plus oxaliplatin-based therapy: the randomized phase III EAGLE study

EAGLE was a randomized, multicenter phase III study which evaluated the superiority of bevacizumab 10 mg/kg plus FOLFIRI compared with bevacizumab 5 mg/kg plus FOLFIRI in patients with mCRC previously treated with first-line bevacizumab plus an oxaliplatin-based regimen. The results suggest that the higher 10 mg/kg dose offers no clear clinical benefit compared with bevacizumab 5 mg/kg in this setting.

Background

A targeted agent combined with chemotherapy is the standard treatment in patients with metastatic colorectal cancer (mCRC). The present phase III study was conducted to compare two doses of bevacizumab combined with irinotecan, 5-fluorouracil/leucovorin (FOLFIRI) in the second-line setting after first-line therapy with bevacizumab plus oxaliplatin-based therapy.

Patients and methods

Patients were randomly assigned to receive FOLFIRI plus bevacizumab 5 or 10 mg/kg in 2-week cycles until disease progression. The primary end point was progression-free survival (PFS), and secondary end points included overall survival (OS), time to treatment failure (TTF), and safety.

Results

Three hundred and eighty-seven patients were randomized between September 2009 and January 2012 from 100 institutions in Japan. Baseline patient characteristics were well balanced between the two groups. Efficacy was evaluated in 369 patients (5 mg/kg, n = 181 and 10 mg/kg, n = 188). Safety was evaluated in 365 patients (5 mg/kg, n = 180 and 10 mg/kg, n = 185). The median PFS was 6.1 versus 6.4 months (hazard ratio, 0.95; 95% confidence interval [CI] 0.75–1.21; P = 0.676), and median TTF was 5.2 versus 5.2 months (hazard ratio, 1.01; 95% CI 0.81–1.25; P = 0.967), respectively, for the bevacizumab 5 and 10 mg/kg groups. Follow-up of OS is currently ongoing. Adverse events, including hypertension and hemorrhage, occurred at similar rates in both groups.

Conclusion

Bevacizumab 10 mg/kg plus FOLFIRI as the second-line treatment did not prolong PFS compared with bevacizumab 5 mg/kg plus FOLFIRI in patients with mCRC. If bevacizumab is continued after first-line therapy in mCRC, a dose of 5 mg/kg is appropriate for use as second-line treatment.

Clinical trial identifier

UMIN000002557.

Identification of protein kinase CK2 inhibitors using solvent dipole ordering virtual screening

Novel protein kinase CK2 inhibitors were identified using the solvent dipole ordering virtual screening method. A total of 26 compounds categorized in 15 distinct scaffold classes inhibited greater than 50% of enzyme activity at 50 μM, and eight exhibited IC50 values less than 10 μM. Most of the identified compounds are lead-like and dissimilar to known inhibitors. The crystal structures of two of the CK2 complexes revealed the high accuracy of the predicted binding modes.

Diffuse Liver Metastasis of Small-Cell Lung Cancer Presenting as Acute Liver Failure and Diagnosed by Transjugular Liver Biopsy: A Rare Case in Whom Nodular Lesions Were Detected by Enhanced CT Examination

Small-cell lung cancer (SCLC) is a subgroup of lung cancer with a high frequency of liver metastasis, which is a predictor of poor prognosis. Diffuse liver metastases of SCLC with no visible nodular lesions in the liver when examined using computed tomography (CT) are relatively rare; however, a few cases with rapid progression to acute liver failure that were diagnosed after death have been reported. In this paper, we report a 63-year-old man with diffuse liver metastases of SCLC that were histologically diagnosed using a transjugular liver biopsy while the patient was alive, even though no lesions were visible during a contrast-enhanced CT examination.

Relationship between clinical factors and severity of esophageal candidiasis according to Kodsi's classification

Severe Candida esophagitis (CE) may lead to development of strictures, hemorrhage, esophagotracheal fistula, and a consequent decrease in quality of life. Although the severity of CE has been classified based on macroscopic findings on endoscopy, the clinical significance remains unknown. The aim of the study was to elucidate the predictive clinical factors for endoscopic severity of CE. Patients who underwent upper endoscopy and answered questionnaires were prospectively enrolled. Smoking, alcohol, human immunodeficiency virus (HIV) infection, diabetes mellitus, chronic renal failure, liver cirrhosis, systemic steroids use, proton pump inhibitor use, H2 blocker use, and gastrointestinal (GI) symptoms were assessed on the same day of endoscopy. GI symptoms including epigastric pain, heartburn, reflux, hunger cramps, nausea, dysphagia, and odynophagia were assessed on a 7-point Likert scale. Endoscopic severity was classified as mild (Kodsi's grade I/II) or severe (grade III/IV). Of 1855 patients, 71 (3.8%) were diagnosed with CE (mild, n = 48; severe, n = 23). In the CE patients, 50.0% (24/48) in the mild group and 23.1% (6/23) in the severe group did not have any GI symptoms. In HIV-infected patients (n = 17), a significant correlation was found between endoscopic severity and declining CD4 cell count (Spearman's rho = -0.90; P < 0.01). Multivariate analysis revealed that GI symptoms (odds ratio [OR], 3.32) and HIV infection (OR, 3.81) were independently associated with severe CE. Patients in the severe group experienced more epigastric pain (P = 0.02), reflux symptoms (P = 0.04), dysphagia (P = 0.05), and odynophagia (P < 0.01) than those in the mild group. Of the GI symptoms, odynophagia was independently associated with severe CE (OR 9.62, P = 0.02). In conclusion, the prevalence of CE in adults who underwent endoscopy was 3.8%. Silent CE was found in both mild and severe cases. Endoscopic severity was associated with characteristic GI symptoms and comorbidity of HIV infection. A decline in immune function correlated with CE disease progression.

De novo design of drug-like molecules by a fragment-based molecular evolutionary approach

This paper describes a similarity-driven simple evolutionary approach to producing candidate molecules of new drugs. The aim of the method is to explore the candidates that are structurally similar to the reference molecule and yet somewhat different in not only peripheral chains but also their scaffolds. The method employs a known active molecule of our interest as a reference molecule which is used to navigate a huge chemical space. The reference molecule is also used to obtain seed fragments. An initial set of individual structures is prepared with the seed fragments and additional fragments using several connection rules. The fragment library is preferably prepared from a collection of known molecules related to the target of the reference molecule. Every fragment of the library can be used for fragment-based mutation. All the fragments are categorized into three classes; rings, linkers, and side chains. New individuals are produced by the crossover and the fragment-based mutation with the fragment library. Computer experiments with our own fragment library prepared from GPCR SARfari verified the feasibility of our approach to drug discovery.

Antagonistic selection factors induce a continuous population divergence in a polymorphism

Understanding the relative importance of selection and stochastic factors in population divergence of adaptive traits is a classical topic in evolutionary biology. However, it is difficult to separate these factors and detect the effects of selection when two or more contrasting selective factors are simultaneously acting on a single locus. In the damselfly Ischnura senegalensis, females exhibit color dimorphism and morph frequencies change geographically. We here evaluated the role of selection and stochastic factors in population divergence of morph frequencies by comparing the divergences in color locus and neutral loci. Comparisons between population pairwise FST for neutral loci and for the color locus did not detect any stochastic factors affecting color locus. Although comparison between population divergence in color and neutral loci using all populations detected only divergent selection, we detected two antagonistic selective factors acting on the color locus, that is, balancing and divergent selection, when considering geographical distance between populations. Our results suggest that a combination of two antagonistic selective factors, rather than stochastic factors, establishes the geographic cline in morph frequency in this system.

Lead evaluation of tetrahydroquinolines as nonsteroidal selective androgen receptor modulators for the treatment of osteoporosis

Tetrahydroquinoline (THQ) was deemed to be a suitable scaffold for our nonsteroidal selective androgen receptor modulator (SARM) concept. We adapted the strategy of switching the antagonist function of cyano-group-containing THQ (CN-THQ) to the agonist function and optimized CN-THQ as an orally available drug candidate with suitable pharmacological and ADME profiles. Based on binding mode analyses and synthetic accessibility, we designed and synthesized a compound that possesses a para-substituted aromatic ring attached through an amide linker. The long-tail THQ derivative 6-acetamido-N-(2-(8-cyano-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinolin-4-yl)-2-methylpropyl)nicotinamide (1 d), which bears a para-acetamide-substituted aromatic group, showed an appropriate in vitro biological profile, as expected. We considered that the large conformational change at Trp741 of the androgen receptor (AR) and the hydrogen bond between 1 d and helix 12 of the AR could maintain the structure of the AR in its agonist form; indeed, 1 d displays strong AR agonistic activity. Furthermore, 1 d showed an appropriate in vivo profile for use as an orally available SARM, displaying clear tissue selectivity, with a separation between its desirable osteoanabolic effect on femoral bone mineral density and its undesirable virilizing effects on the uterus and clitoral gland in a female osteoporosis model.

Enterovirus 71 encephalomyelitis and Japanese encephalitis can be distinguished by topographic distribution of inflammation and specific intraneuronal detection of viral antigen and RNA

AIMS

To investigate if two important epidemic viral encephalitis in children, Enterovirus 71 (EV71) encephalomyelitis and Japanese encephalitis (JE) whose clinical and pathological features may be nonspecific and overlapping, could be distinguished.

METHODS

Tissue sections from the central nervous system of infected cases were examined by light microscopy, immunohistochemistry and in situ hybridization.

RESULTS

All 13 cases of EV71 encephalomyelitis collected from Asia and France invariably showed stereotyped distribution of inflammation in the spinal cord, brainstem, hypothalamus, cerebellar dentate nucleus and, to a lesser extent, cerebral cortex and meninges. Anterior pons, corpus striatum, thalamus, temporal lobe, hippocampus and cerebellar cortex were always uninflamed. In contrast, the eight JE cases studied showed inflammation involving most neuronal areas of the central nervous system, including the areas that were uninflamed in EV71 encephalomyelitis. Lesions in both infections were nonspecific, consisting of perivascular and parenchymal infiltration by inflammatory cells, oedematous/necrolytic areas, microglial nodules and neuronophagia. Viral inclusions were absent.

CONCLUSIONS

Immunohistochemistry and in situ hybridization assays were useful to identify the causative virus, localizing viral antigens and RNA, respectively, almost exclusively to neurones. The stereotyped distribution of inflammatory lesions in EV71 encephalomyelitis appears to be very useful to help distinguish it from JE.

Anti-androgenic effects of S-40542, a novel non-steroidal selective androgen receptor modulator (SARM) for the treatment of benign prostatic hyperplasia

BACKGROUND

Selective androgen receptor modulators (SARMs) would provide alternative therapeutic agent for androgen-related diseases. We identified a tetrahydroquinoline (THQ) derivative, 1-(8-nitro-3a, 4, 5, 9b-tetrahydro-3H-cyclopenta[c]quinolin-4-yl) ethane-1, 2-diol (S-40542) as a novel SARM antagonist.

METHODS

Affinity for nuclear receptors of S-40542 was evaluated in receptor-binding studies. Androgen receptor (AR) transcriptional activity of S-40542 was investigated by luciferase reporter assay in DU145AR cells. Normal and benign prostatic hyperplasia (BPH) model rats were repeatedly treated with S-40542 and flutamide. The tissue weights of prostate and levator ani muscle as well as blood levels of testosterone and luteinizing hormone were measured.

RESULTS

S-40542 bound to the AR with high affinity. S-40542 at relatively high concentrations increased the transcriptional activity. This agent also showed a concentration-dependent AR antagonistic action in the presence of 1 nM 5α-dihydrotestosterone. Repeated treatment with S-40542 and flutamide decreased dose-dependently the weights of the prostate to a similar extent. In contrast, the tissue weight-reducing effect by S-40542 treatment on the levator ani muscle was much weaker than that of flutamide. S-40542 had little effect on the blood level of testosterone and luteinizing hormone, whereas flutamide increased the level of both hormones. Furthermore, S-40542 decreased dose-dependently prostate weight of BPH rats.

CONCLUSIONS

The current results indicate that S-40542 possesses the prostate-selective SARM activity, suggestive of clinical benefit against benign prostate hyperplasia. THQ compounds may be useful for the research of mode of action of SARMs and for the development of safe SARM antagonists.

Predictive value of endoscopic findings in the diagnosis of active intestinal amebiasis

Endoscopic diagnosis of amebic colitis can be difficult because its appearance may mimic other forms of colonic disease. The aim of this study was to identify predictive endoscopic findings for amebic colitis. Patients with suspected amebic colitis based on distinctive endoscopic findings such as aphthae or erosions, ulcers, exudates, or a bump, were included in the study. A total of 157 patients were selected, 50 of whom had amebic colitis. The sensitivity and specificity of endoscopic findings that were significantly associated with amebic colitis were: cecal lesions (80% and 54%), multiple number of lesions (96% and 29%), presence of aphthae or erosions (84% and 37%), and presence of exudate (88% and 74%). Multivariate analysis revealed that the best combination of findings to predict amebic colitis was the presence of cecal lesions, multiple lesions, and exudates, which corresponded to an area under the receiver operating characteristic curve of 0.89 (95% confidence interval 0.82-0.95).

Recurrence of colonic diverticular bleeding and associated risk factors

AIM

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

METHOD

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

RESULTS

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

CONCLUSION

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

Metal-ligand interactions: an analysis of zinc binding groups using the Protein Data Bank

In the present study, we investigated zinc binding groups (ZBGs) using the coordinates of protein-ligand complex structures obtained from the Protein Data Bank. The distance from the zinc to the nearest ligand atom was measured to determine whether the atom was part of the ZBG. The most frequently found ZBG was carboxylate, followed by sulfonamide, hydroxamate, and phosphonate/phosphate. Because it was found that few heteroatoms, such as nitrogen, oxygen, and sulfur atoms, interacted with zinc, ideal distances between the zinc and these heteroatoms were identified. Whereas carboxylates bound to the zinc via both monodentate and bidentate interactions, the hydroxamates bound dominantly in a bidentate manner. These results will aid in the design of new inhibitors with the potential to interact with zinc in the target protein.