Cancer Detection Rate and Abnormal Interpretation Rate of Prostate MRI in Patients With Low-Grade Cancer

PURPOSE

The aim of this study was to evaluate the utility of cancer detection rate (CDR) and abnormal interpretation rate (AIR) in prostate MRI for patients with low-grade prostate cancer (PCa).

METHODS

This three-center retrospective study included patients who underwent prostate MRI from 2017 to 2021 with known low-grade PCa (Gleason score 6) without prior treatment. Patient-level highest Prostate Imaging Reporting & Data System (PI-RADS®) score and pathologic diagnosis within 1 year after MRI were used to evaluate the diagnostic performance of prostate MRI in detecting clinically significant PCa (csPCa; Gleason score ≥ 7). The metrics AIR, CDR, and CDR adjusted for pathologic confirmation rate were calculated. Radiologist-level AIR-CDR plots were shown. Simulation AIR-CDR lines were created to assess the effects of different diagnostic performances of prostate MRI and the prevalence of csPCa.

RESULTS

A total of 3,207 examinations were interpreted by 33 radiologists. Overall AIR, CDR, and CDR adjusted for pathologic confirmation rate at PI-RADS 3 to 5 (PI-RADS 4 and 5) were 51.7% (36.5%), 22.1% (18.8%), and 30.7% (24.6%), respectively. Radiologist-level AIR and CDR at PI-RADS 3 to 5 (PI-RADS 4 and 5) were in the 36.8% to 75.6% (21.9%-57.5%) range and the 16.3%-28.7% (10.9%-26.5%) range, respectively. In the simulation, changing parameters of diagnostic performance or csPCa prevalence shifted the AIR-CDR line.

CONCLUSIONS

The authors propose CDR and AIR as performance metrics in prostate MRI and report reference performance values in patients with known low-grade PCa. There was variability in radiologist-level AIR and CDR. Combined use of AIR and CDR could provide meaningful feedback for radiologists to improve their performance by showing relative performance to other radiologists.

Cancer Detection Rate and Abnormal Interpretation Rate of Prostate MRI Performed for Clinical Suspicion of Prostate Cancer

PURPOSE

To report cancer detection rate (CDR) and abnormal interpretation rate (AIR) in prostate MRI performed for clinical suspicion of prostate cancer (PCa).

MATERIALS AND METHODS

This retrospective single-institution, three-center study included patients who underwent MRI for clinical suspicion of PCa between 2017 and 2021. Patients with known PCa were excluded. Patient-level Prostate Imaging-Reporting and Data System (PI-RADS) score was extracted from the radiology report. AIR was defined as number of abnormal MRI (PI-RADS score 3-5) / total number of MRIs. CDR was defined as number of clinically significant PCa (csPCa: Gleason score ≥7) detected at abnormal MRI / total number of MRI. AIR, CDR, and CDR adjusted for pathology confirmation rate were calculated for each of three centers and pre-MRI biopsy status (biopsy-naive and previous negative biopsy).

RESULTS

A total of 9,686 examinations (8,643 unique patients) were included. AIR, CDR, and CDR adjusted for pathology confirmation rate were 45.4%, 23.8%, and 27.6% for center I; 47.2%, 20.0%, and 22.8% for center II; and 42.3%, 27.2%, and 30.1% for center III, respectively. Pathology confirmation rate ranged from 81.6% to 88.0% across three centers. AIR and CDR for biopsy-naive patients were 45.5% to 52.6% and 24.2% to 33.5% across three centers, respectively, and those for previous negative biopsy were 27.2% to 39.8% and 11.7% to 14.2% across three centers, respectively.

CONCLUSION

We reported CDR and AIR in prostate MRI for clinical suspicion of PCa. CDR needs to be adjusted for pathology confirmation rate and pre-MRI biopsy status for interfacility comparison.

Preemptive Embolization of the Lumbar Arteries and Inferior Mesenteric Artery to Prevent Abdominal Aortic Aneurysm Enlargement Associated with Type 2 Endoleak Following Endovascular Aneurysm Repair

Purpose

This study aims to evaluate the efficacy of preemptive embolization (PE) of the lumbar arteries (LAs) and inferior mesenteric artery (IMA) (PELI) for preventing abdominal aortic aneurysm (AAA) enlargement associated with type 2 endoleak (T2EL).

Material and Methods

Patients who underwent endovascular aneurysm repair (EVAR) between January 2015 and December 2020 were classified into the control (without PE), IMA (PE of a patent IMA with a diameter ≥2.5 mm), and PELI (PE of patent LAs with a diameter ≥2 mm and IMA) groups. The rate of freedom from AAA enlargement following EVAR (enlargement ≥5 mm from pre-EVAR) was compared using the log-rank test. The prevalence of T2EL at 6 months and 1 year after EVAR was compared using Fisher's exact test.

Results

The cumulative rates of freedom from AAA enlargement at 54 months after EVAR (maximum observational period in the PELI group) were as follows: control group, 77.5%; IMA group, 62.5%; and PELI group, 100%. The mean CT follow-up periods of the control, IMA, and PELI groups were 46.4 ± 22.3, 31.1 ± 20.6, and 22.9 ± 15.5 months, respectively. None of the 31 patients in the PELI group experienced AAA enlargement after EVAR, whereas 2 out of the 16 patients in the IMA group and 20 out of the 98 patients in the control group had AAA enlargement. No significant differences were observed in the rate of freedom from AAA enlargement (PELI group vs. IMA group, P = 0.11; PELI group vs. control group, P = 0.11). The prevalence of T2EL was significantly lower in the PELI group than in the control group at 6 months (13.6% in PELI group vs. 42.1% in control group, P = 0.02) and 1 year (14.3% in PELI group vs. 40.0% in control group, P = 0.04).

Conclusions

PELI was significantly associated with a low prevalence of T2EL and may prevent T2EL-associated AAA enlargement.

Decreased prostate MRI cancer detection rate due to moderate to severe susceptibility artifacts from hip prosthesis

OBJECTIVES

To evaluate the impact of susceptibility artifacts from hip prosthesis on cancer detection rate (CDR) in prostate MRI.

MATERIALS AND METHODS

This three-center retrospective study included prostate MRI studies for patients without known prostate cancer between 2017 and 2021. Exams with hip prosthesis were searched on MRI reports. The degree of susceptibility artifact on diffusion-weighted images was retrospectively categorized into mild, moderate, and severe (> 66%, 33-66%, and < 33% of the prostate volume are evaluable) by blind reviewers. CDR was defined as the number of exams with Gleason score ≥7 detected by MRI (PI-RADS ≥3) divided by the total number of exams. For each artifact grade, control exams without hip prosthesis were matched (1:6 match), and CDR was compared. The degree of CDR reduction was evaluated with ratio, and influential factors were evaluated by expanding the equation.

RESULTS

Hip arthroplasty was present in 548 (4.8%) of the 11,319 MRI exams. CDR of the cases and matched control exams for each artifact grade were as follows: mild (n = 238), 0.27 vs 0.25, CDR ratio = 1.09 [95% CI: 0.87-1.37]; moderate (n = 143), 0.18 vs 0.27, CDR ratio = 0.67 [95% CI: 0.46-0.96]; severe (n = 167), 0.22 vs 0.28, CDR ratio = 0.80 [95% CI: 0.59-1.08]. When moderate and severe artifact grades were combined, CDR ratio was 0.74 [95% CI: 0.58-0.93]. CDR reduction was mostly attributed to the increased frequency of PI-RADS 1-2.

CONCLUSION

With moderate to severe susceptibility artifacts from hip prosthesis, CDR was decreased to 74% compared to the matched control.

CLINICAL RELEVANCE STATEMENT

Moderate to severe susceptibility artifacts from hip prosthesis may cause a non-negligible CDR reduction in prostate MRI. Expanding indications for systematic prostate biopsy may be considered when PI-RADS 1-2 was assigned.

KEY POINTS

• We proposed cancer detection rate as a diagnostic performance metric in prostate MRI. • With moderate to severe susceptibility artifacts secondary to hip arthroplasty, cancer detection rate decreased to 74% compared to the matched control. • Expanding indications for systematic prostate biopsy may be considered when PI-RADS 1-2 is assigned.

Severe TAFRO Syndrome Mimicking Hepatorenal Syndrome Successfully Treated with a Multidisciplinary Approach: A Case Report and Literature Review

Finding the ideal balance between efficacy and safety of immunosuppression is challenging, particularly in cases of severe TAFRO syndrome. We herein report a 60-year-old man diagnosed with grade 5 TAFRO syndrome mimicking hepatorenal syndrome that was successfully treated by glucocorticoid, tocilizumab, and cyclosporin despite virus infection. Furthermore, by examining 14 peer-reviewed remission cases, we revealed that the recovery periods among inflammation, renal dysfunction, and thrombocytopenia were quite different, with recovery from thrombocytopenia notably slow. All patients requiring dialysis were successfully withdrawn from dialysis, and the reversibility from kidney injury was good. This clinical information will help clinicians plan treatments and tailor the intensity of immunosuppression.

Artificial intelligence-powered software detected more than half of the liver metastases overlooked by radiologists on contrast-enhanced CT

PURPOSE

To evaluate the sensitivity of artificial intelligence (AI)-powered software in detecting liver metastases, especially those overlooked by radiologists.

METHODS

Records of 746 patients diagnosed with liver metastases (November 2010-September 2017) were reviewed. Images from when radiologists first diagnosed liver metastases were reviewed, and prior contrast-enhanced CT (CECT) images were checked for availability. Two abdominal radiologists classified the lesions into overlooked lesions (all metastases missed by radiologists on prior CECT) and detected lesions (all metastases if any of them were correctly identified and invisible on prior CECT or those with no prior CECT). Finally, images from 137 patients were identified, 68 of which were classified as "overlooked cases." The same radiologists created the ground truth for these lesions and compared them with the software's output at 2-month intervals. The primary endpoint was the sensitivity in detecting all liver lesion types, liver metastases, and liver metastases overlooked by radiologists.

RESULTS

The software successfully processed images from 135 patients. The per-lesion sensitivity for all liver lesion types, liver metastases, and liver metastases overlooked by radiologists was 70.1%, 70.8%, and 55.0%, respectively. The software detected liver metastases in 92.7% and 53.7% of patients in detected and overlooked cases, respectively. The average number of false positives was 0.48 per patient.

CONCLUSION

The AI-powered software detected more than half of liver metastases overlooked by radiologists while maintaining a relatively low number of false positives. Our results suggest the potential of AI-powered software in reducing the frequency of overlooked liver metastases when used in conjunction with the radiologists' clinical interpretation.

Long-term efficacy and risk factors for stent occlusion in portal vein stent placement: a multi-institutional retrospective study

Background

Surgical treatment for PV (portal vein) stenosis/occlusion can pose a fatal risk of massive bleeding from severe adhesions and collateral vessel formation. PV stents placement is a minimally invasive and effective procedure for PV stenosis/occlusion, but PV stents sometimes occlude. The relationship between post-stent PV hemodynamics and stent occlusion has not been thoroughly investigated. Certain precautions during PV stent placement may reduce the risk of stent occlusion. This study aimed to evaluate long-term outcomes of PV stent patency and investigate factors including PV hemodynamics associated with stent occlusion.

Materials and methods

Thirty-four consecutive patients with PV stenosis/occlusion who underwent PV stent placement in four institutions between December 2006 and February 2021 were retrospectively examined. The primary study endpoints were technical success, clinical success, and cumulative stent patency rate. The secondary endpoints were risk factors of stent occlusion. A univariable Cox proportional hazards model with sixteen variables was used to determine predictors of stent occlusion. Factors with p-value ≤ 0.1 in univariable analysis were included in the multivariable analysis. Alpha was set at 0.05.

Results

Technical and clinical success rates were 88.2% and 79.4%, respectively. Six patients (17.7%) experienced stent occlusion. The cumulative stent patency rate at six months, one year, and three years was 79.1%, 79.1%, and 65.9%, respectively. In the univariate analysis, the variables with p-value ≤ 0.1 were lesion length > 4 cm, hepatofugal collateral vein visualization after stent placement, and residual stenosis > 30% after stent placement. In the multivariate analysis, residual stenosis > 30% after stent placement was significantly associated with stent occlusion (hazard ratio, 10.80; 95% confidence interval, 1.08–108.44; p = 0.04).

Conclusion

PV stent placement was technically feasible and effective in improving portal hypertension. However, stent occlusion was not uncommon. Residual stenosis > 30% after stent placement was significantly associated with stent occlusion. We should pay attention to correctly assess the range of stenosis and release the stenosis as much as possible.

Chest wall systemic artery-to-pulmonary artery vascular malformation treated by embolization of feeders and drainers: A case report

A 74-year-old woman presented with progressive dyspnea. Computed tomography revealed a large systemic artery-to-pulmonary artery vascular malformation (VM) on the right chest wall. Embolization of the VM was performed. First, the main drainers of the VM were retrogradely selected from the segmental pulmonary arteries and embolized using microcoils. Second, 2 main feeders of the VM were selected and embolized with N-butyl cyanoacrylate. Thus, marked flow reduction in the VM was achieved, and the patient's symptom improved dramatically. We believe that embolization of both feeders and drainers is an effective technique for treatment of a chest wall systemic artery-to-pulmonary artery VM.

A rare case of atypical ANCA-associated vasculitis without crescents overlapping with invasive pulmonary aspergillosis, successfully treated to remission with intravenous immunoglobulin therapy

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is life-threatening without treatment, but aggressive immunosuppression increases the risk of exacerbating a coexisting infection. Finding the balance between efficacy and safety of immunosuppression is challenging. We describe a 74-year-old man who was diagnosed with AAV following the aggravation of chronic pulmonary aspergillosis that required an aggressive antifungal agent. The laboratory data on admission demonstrated severe kidney failure requiring hemodialysis. Due to the active infection, we chose intravenous immunoglobulin (IVIg) as a low-risk initial treatment, which remarkably improved renal dysfunction (serum creatinine; 16.7 mg/dL-3.7 mg/dL) and systemic inflammation. Renal biopsy that was performed after renal recovery revealed atypical ANCA-associated nephritis without cellular crescents but with massive arteritis with multiple vascular sizes and diffuse interstitial inflammation. Despite these active AAV findings, adding plasma exchange therapy (PE) and low-dose steroids were sufficient to induce remission. The main pathogenesis of severe renal impairment was probably the reduction of blood flow, resulting from occlusions of small arteries by inflammatory cell infiltration and vascular endothelial injury due to AAV. Combination treatment with antifungal agents, IVIg, PE, and low-dose steroid treatment led to complete resolution of vasculitis. The specific histological findings and the good response to treatments suggest that pulmonary aspergillosis might trigger vasculitis through induction of ANCA antigen expression. IVIg could be an important option especially for cases of AAV associated with pulmonary aspergillosis.

Identifying patients with atrial fibrillation during sinus rhythm on ECG: confirming the utility of artificial intelligence algorithm in a small-scale cohort without structural heart diseases

Background

Detection of atrial fibrillation (AF) out of electrocardiograph (ECG) on sinus rhythm (SR) using artificial intelligence (AI) algorithm has been widely studied within recent couple of years. Generally, it is believed that a huge number of ECGs are necessary for developing an AI-enabled ECG to be adequate to correspond to a lot of minor variations of ECGs. For example, structural heart diseases have typical ECG characteristics, but they could be a noise for the purpose of detecting the small signs of electrocardiographic signature of AF. We hypothesized that when patients with structural heart diseases are excluded, AI-enabled ECG for identifying patients with AF can be developed with a small number of ECGs.

Methods

We developed an AI-enabled ECG using a convolutional neural network to detect the electrocardiographic signature of AF present during normal sinus rhythm (NSR) using a digital, standard 10-second, 12-lead ECGs. We included all patients who newly visited the Cardiovascular Institute with at least one NSR ECG between Feb 1, 2010, and March 31, 2018. We classified patients with at least one ECG with a rhythm of AF as positive for AF (AF label) and others as negative for AF (SR label). We allocated ECGs to the training, internal validation, and testing datasets in a 7:1:2 ratio. We calculated the area under the curve (AUC) of the receiver operating characteristic curve for the internal validation dataset to select a probability threshold, which we applied to the testing dataset. We evaluated model performance on the testing dataset by calculating the AUC and the sensitivity, specificity, F1 score, and accuracy with two-sided 95% confidence intervals (CIs).

Results

We totally included 19170 patients with 12-lead ECG. After excluding patients with structural heart diseases, 12825 patients with NSR ECGs at the initial visit were identified (1262 were clinically diagnosed as AF anytime during the time course and 11563 were never diagnosed as AF). Of 11563 non-AF patients, 1818 patients who were followed over 1095 days were selected for the analysis with the SR label, to secure the robustness for maintaining SR. Of 1262 AF patients, 251 patients were selected for the analysis with the AF label, of whom a NSR ECG within 31 days before or after the index AF ECG (the first AF ECG during the time course) could be obtained. In the patients with AF label, the NSR ECG of which the date was the nearest to the index AF ECG was selected for the analysis. The AI-enabled ECG showed an AUC of 0.88 (0.84–0.92) with sensitivity 81% (72–88), specificity 80% (77–83), F1 score 50% (43–57), and overall accuracy 80% (78–83).

Conclusion

An AI-enabled ECG acquired during NSR allowed identification of patients with AF in a small population without structural heart diseases.

Funding Acknowledgement

Type of funding sources: None.

Convolutional neural network for classifying primary liver cancer based on triple-phase CT and tumor marker information: a pilot study

PURPOSE

To develop convolutional neural network (CNN) models for differentiating intrahepatic cholangiocarcinoma (ICC) from hepatocellular carcinoma (HCC) and predicting histopathological grade of HCC.

MATERIALS AND METHODS

Preoperative computed tomography and tumor marker information of 617 primary liver cancer patients were retrospectively collected to develop CNN models categorizing tumors into three categories: moderately differentiated HCC (mHCC), poorly differentiated HCC (pHCC), and ICC, where the histopathological diagnoses were considered as ground truths. The models processed manually cropped tumor with and without tumor marker information (two-input and one-input models, respectively). Overall accuracy was assessed using a held-out dataset (10%). Area under the curve, sensitivity, and specificity for differentiating ICC from HCCs (mHCC + pHCC), and pHCC from mHCC were also evaluated. We assessed two radiologists' performance without tumor marker information as references (overall accuracy, sensitivity, and specificity). The two-input model was compared with the one-input model and radiologists using permutation tests.

RESULTS

The overall accuracy was 0.61, 0.60, 0.55, 0.53 for the two-input model, one-input model, radiologist 1, and radiologist 2, respectively. For differentiating pHCC from mHCC, the two-input model showed significantly higher specificity than radiologist 1 (0.68 [95% confidence interval: 0.50-0.83] vs 0.45 [95% confidence interval: 0.27-0.63]; p = 0.04).

CONCLUSION

Our CNN model with tumor marker information showed feasibility and potential for three-class classification within primary liver cancer.

Survival in patients with chronic thromboembolic pulmonary hypertension in the modern management era

Background

The management of non-operable chronic thromboembolic pulmonary hypertension (CTEPH) has recently evolved with the availability of balloon pulmonary angioplasty (BPA) and pulmonary vasodilators. We launched BPA program since 2011. The aim was to analyze survival and treatment efficacy in the modern management era.

Method and result

We retrospectively reviewed data from 143 consecutive CTEPH patients diagnosed in our university from January 2011 (i.e. after the availability of BPA) to December 2019. Forty-one patients underwent PEA, in these 25 patients underwent additional BPA (Hybrid group) and other patients were treated with only PEA (PEA group). Ninety patients underwent BPA (BPA group), remaining 12 patients had not undergone any interventional treatments. The 1- and 5-year survival rates of operated patients (n=41) were 97.4% and 90.0%, compared to96.9% and 86.9% in not-operated patients (n=102), respectively (p=0.579) (Figure). There was no death in Hybrid group. Percent decrease of pulmonary vascular resistance in PEA group, Hybrid group, BPA group were −75.4±9.9%, −74.3±11.8%, −56.3±22.2%, respectively (p&lt;0.01, one-way ANOVA). Absolute decrease of mean pulmonary artery pressure in each groups were −20.3±9.5mmHg, −24.5±8.8mmHg, −16.4±9.2mmHg, respectively (p&lt;0.01, one-way ANOVA).

Conclusion

There was no longer significant difference of long-term survival between operated and not-operated CTEPH. Moreover, Hybrid approach might have the potential to lead notable improvement in the prognosis of CTEPH. BPA and PEA would be mutually complementary therapies in the modern management era.

Figure 1

Funding Acknowledgement

Type of funding source: None

Quantitative and Qualitative Evaluation of Convolutional Neural Networks with a Deeper U-Net for Sparse-View Computed Tomography Reconstruction

RATIONALE AND OBJECTIVES

To evaluate the utility of a convolutional neural network (CNN) with an increased number of contracting and expanding paths of U-net for sparse-view CT reconstruction.

MATERIALS AND METHODS

This study used 60 anonymized chest CT cases from a public database called "The Cancer Imaging Archive". Eight thousand images from 40 cases were used for training. Eight hundred and 80 images from another 20 cases were used for quantitative and qualitative evaluation, respectively. Sparse-view CT images subsampled by a factor of 20 were simulated, and two CNNs were trained to create denoised images from the sparse-view CT. A CNN based on U-net with residual learning with four contracting and expanding paths (the preceding CNN) was compared with another CNN with eight contracting and expanding paths (the proposed CNN) both quantitatively (peak signal to noise ratio, structural similarity index), and qualitatively (the scores given by two radiologists for anatomical visibility, artifact and noise, and overall image quality) using the Wilcoxon signed-rank test. Nodule and emphysema appearance were also evaluated qualitatively.

RESULTS

The proposed CNN was significantly better than the preceding CNN both quantitatively and qualitatively (overall image quality interquartile range, 3.0-3.5 versus 1.0-1.0 reported from the preceding CNN; p < 0.001). However, only 2 of 22 cases used for emphysematous evaluation (2 CNNs for every 11 cases with emphysema) had an average score of ≥ 2 (on a 3 point scale).

CONCLUSION

Increasing contracting and expanding paths may be useful for sparse-view CT reconstruction with CNN. However, poor reproducibility of emphysema appearance should also be noted.

Next-generation sequencing for patients with non-obstructive azoospermia: implications for significant roles of monogenic/oligogenic mutations

Azoospermia affects up to 1% of adult men. Non-obstructive azoospermia is a multifactorial disorder whose molecular basis remains largely unknown. To date, mutations in several genes and multiple submicroscopic copy-number variations (CNVs) have been identified in patients with non-obstructive azoospermia. The aim of this study was to clarify the contribution of nucleotide substitutions in known causative genes and submicroscopic CNVs in the genome to the development of non-obstructive azoospermia. To this end, we conducted sequence analysis of 25 known disease-associated genes using next-generation sequencing and genome-wide copy-number analysis using array-based comparative genomic hybridization. We studied 40 Japanese patients with idiopathic non-obstructive azoospermia. Functional significance of molecular alterations was assessed by in silico analyses. As a result, we identified four putative pathogenic mutations, four rare polymorphisms possibly associated with disease risk, and four probable neutral variants in 10 patients. These sequence alterations included a heterozygous splice site mutation in SOHLH1 and a hemizygous missense substitution in TEX11, which have been reported as causes of non-obstructive azoospermia. Copy-number analysis detected five X chromosomal or autosomal CNVs of unknown clinical significance, in addition to one known pathogenic Y chromosomal microduplication. Five patients carried multiple molecular alterations. The results indicate that monogenic and oligogenic mutations, including those in SOHLH1 and TEX11, account for more than 10% of cases of idiopathic non-obstructive azoospermia. Furthermore, this study suggests possible contributions of substitutions in various genes as well as submicroscopic CNVs on the X chromosome and autosomes to non-obstructive azoospermia, which require further validation.

Electrocatalytic synthesis of ammonia by surface proton hopping

Highly efficient ammonia synthesis at a low temperature is desirable for future energy and material sources. We accomplished efficient electrocatalytic low-temperature ammonia synthesis with the highest yield ever reported. The maximum ammonia synthesis rate was 30 099 μmol gcat-1 h-1 over a 9.9 wt% Cs/5.0 wt% Ru/SrZrO3 catalyst, which is a very high rate. Proton hopping on the surface of the heterogeneous catalyst played an important role in the reaction, revealed by in situ IR measurements. Hopping protons activate N2 even at low temperatures, and they moderate the harsh reaction condition requirements. Application of an electric field to the catalyst resulted in a drastic decrease in the apparent activation energy from 121 kJ mol-1 to 37 kJ mol-1. N2 dissociative adsorption is markedly promoted by the application of the electric field, as evidenced by DFT calculations. The process described herein opens the door for small-scale, on-demand ammonia synthesis.

Engineering a gene silencing viral construct that targets the cat hypothalamus to induce permanent sterility: An update

The intent of this contribution is to provide an update of the progress we have made towards developing a method/treatment to permanently sterilize cats. Our approach employs two complementary methodologies: RNA interference (RNAi) to silence genes involved in the central control of reproduction and a virus-based gene therapy system intended to deliver RNAi selectively to the hypothalamus (where these genes are expressed) via the systemic administration of modified viruses. We selected the hypothalamus because it contains neurons expressing Kiss1 and Tac3, two genes essential for reproduction and fertility. We chose the non-pathogenic adeno-associated virus (AAV) as a vector whose tropism could be modified to target the hypothalamus. The issues that must be overcome to utilize this vector as a delivery vehicle to induce sterility include modification of the wild-type AAV to target the hypothalamic region of the brain with a simultaneous reduction in targeting of peripheral tissues and non-hypothalamic brain regions, identification of RNAi targets that will effectively reduce the expression of Kiss1 and Tac3 without off-target effects, and determination if neutralizing antibodies to the AAV serotype of choice are present in cats. Successful resolution of these issues will pave the way for the development of a powerful tool to induce the permanent sterility in cats.

Determinant factors of postoperative recurrence of endometriosis: difference between endometrioma and pain

OBJECTIVE

Although the postoperative use of hormonal treatment for endometriosis is recommended in the European Society of Human Reproduction and Embryology guidelines to prevent the recurrence of endometriosis-associated dysmenorrhoea, hormonal treatment may not be necessary for all patients who undergo surgical treatment for endometriosis. The aim of this study was to clarify the determinant factors that predict the recurrence of endometriosis after surgery in order to develop personalized hormonal treatment recommendations. Factors associated with the recurrence of endometrioma and pain were investigated independently to identify the likelihood of recurrence in each individual patient.

STUDY DESIGN

Between 2008 and 2013, 352 patients underwent surgery and were diagnosed with endometriosis based on pathological findings at the study hospital. Among these patients, 191 experienced a recurrence of endometrioma in the absence of pre- or postoperative hormonal treatment. Various clinical factors such as pre-operative pain, intra-operative findings and postoperative improvement of pain were compared between patients who experienced recurrence after surgery and those who did not.

RESULTS

The cumulative 5-year recurrence rate of endometrioma was 28.7% among the 191 patients who did not undergo pre- or postoperative hormonal treatment. Significant differences were detected in maximum tumour diameter, revised American Society for Reproductive Medicine score (r-ASRM score), operative time and operative blood loss between patients in the recurrent endometrioma group and the non-recurrent endometrioma group; only the r-ASRM score was significantly correlated with recurrence of endometrioma in the multivariate analysis. The cumulative 5-year rate of persistent/recurrent pain was 33.4%. There were significant differences in the postoperative improvement of pain between the persistent/recurrent pain group and the non-recurrent pain group according to the univariate and multivariate analyses.

CONCLUSION

This study suggests that the risk factors for recurrence of endometrioma differ from the risk factors for recurrence of pain. The use of postoperative hormonal treatment should be considered based on the dominant risk factors and needs of each patient.

Determination of mitochondrial cytochrome B gene sequence for red deer (Cervus elaphus) and the differentiation of closely related deer meats

The cytochrome b gene sequence for red deer was determined using the Dye Terminator Cycle Sequencing method and used for identification of deer meat in meat and meat products. Red deer showed a similarity of 94.1, 84.0, 81.1, 85.5 and 85.6% to sika deer (Cervus nippon), bovine, pigs, sheep and goats, respectively. To differentiate the deer meat, oligonucleotide primers RD-1(5'-TCATCGCAGCACTCGCTATAGTACACT-3'), RD-2(5'-ATCTCCAAGTAGGTCTGGTGCGAATAA-3') were designed for the region of the cytochrome b gene of red deer. The PCR amplified 194 bp fragments from red and sika deer, but no fragments from bovine, pig, chicken, sheep, goat, horse and rabbit DNA. Although cooking the meats reduced the PCR products, red deer could still be detected in meat heated at 120 °C. To discriminate between red and sika deer, these PCR products were digested by a restriction enzyme (EcoRI,BamHI,ScaI) and analyzed by 4% agorose gel electrophoresis. As a result, the red deer fragment was digested by EcoRI to 67/127 bp fragments but not by BamHI and ScaI. The sika deer fragment was digested to 48/146 bp and 49/145 bp fragments with the two other enzymes, and thus it is possible to differentiate between the two kinds of deer from the digestion pattern of restriction enzymes.

Useful Host-Vector Systems in Bacillus stearothermophilus

We isolated a highly transformable thermophile, Bacillus stearothermophilus SIC1, which exhibited the following features. The growth temperature ranged from 45 to 65 degrees C in L broth. The maximum cell concentration in 2L broth (2% tryptone, 1% yeast extract, 0.5% NaCl, pH 7.2) was determined as an optical density at 660 nm of 7.8, and the generation time was 11 min at 60 degrees C. Strain SIC1 was a prototroph and was transformed by the protoplast procedure not only with repB plasmids (high-copy-number plasmids such as pTB913 and pUB110) but also with repA plasmids (low-copy-number plasmids such as pTB53). Transformation efficiencies with repB and repA plasmids were about 2 x 10 to 5 x 10 and 5 x 10 transformants per mug of DNA, respectively. The transformant carrying plasmid pTB913Y/K could grow at 63 degrees C in the presence of kanamycin. The regeneration frequency of protoplasts was 60%, and only 1 day was needed for regeneration at 55 degrees C.

[Malignant pleural mesothelioma]

Malignant pleural mesothelioma carries a poor prognosis, for which no standard therapy has been established. We report 15 cases of malignant pleural mesothelioma experienced since 2000 focusing on their clinical features. They included 14 male and 1 female aged 38 to 81 (62.8 on average) years. All patients were diagnosed by pleural biopsy under thoracoscopic guidance. Histology of the pleural biopsy specimen showed epithelial mesothelioma in 8 patients, biphasic mesothelioma in 3, sarcomatous mesothelioma in 2 and desmoplastic malignant mesothelioma (DMM) in 2. Twelve patients received chemotherapy. Of these, 3 were followed by surgery. In addition to 2 of these 3 patients, 2 underwent extrapleural pneumonectomy (EPP) without adjuvant treatment. Remaining 1 received palliative treatment only. As a result, 6 patients are surviving, 7 died of primary diseases and 2 died of other diseases. The longest survival time with chemotherapy is 41 months in a surviving patient with epithelial mesothelioma and that with EPP is 25 months in a surviving patient with DMM. The 2-year survival rate of the 14 patients was 44.4% and the median survival time in patients with epithelial mesothelioma was 30.6 months.

Practice patterns of Japanese physicians in urologic surveillance and management of spinal cord injury patients

STUDY DESIGN

Analysis of answers to a new questionnaire.

OBJECTIVE

To examine current practice patterns of physicians in the urological surveillance and management of spinal cord injury (SCI) patients in Japan.

SETTING

Nationwide questionnaire survey to physicians in Japan.

METHODS

A Japanese version of the 14-item questionnaire survey carried out in US was mailed to 770 members of the Japanese Neurogenic Bladder Society (JNBS).

RESULTS

We received answers to our questionnaire from 333 (43.2%) members of JNBS. The responders were all urologists. For surveillance of the upper urinary tract (UUT), 239 (71.8%) respondents preferred abdominal ultrasound. Cystometry was performed routinely by 174 (52.3%) respondents for the evaluation of vesicourethral function. Cystoscopy was carried out in cases of hematuria (88.0%) and bladder stone (55.3%). Surveillance of the urinary tract was performed every year in 154 (46.2%). For detection of bladder cancer, which 119 (37.9%) respondents have experienced, 94.9% physicians perform cystoscopy, 76.3% urinary cytology, and 60.4% ultrasound. For initial treatment of detrusor-sphincter dyssynergia (DSD), 225 (69.2%) respondents chose alpha-blocker, and 94 (28.9%) chose clean intermittent catheterization (CIC) with/without anticholinergic agent(s). For initial treatment of overactive bladder, 245 (74.7%) chose anticholinergic agent(s) only and 63 (19.2%) chose anticholinergic agent(s) with CIC. For initial treatment of areflexic bladder, 233 (73.7%) chose CIC and 63 (19.9%) chose Credé maneuver or tapping.

CONCLUSIONS

This survey shows that there are some differences in urological surveillance and management of SCI patients between Japan and the US. Reasons for the discrepancy should be examined.

Carboplatin hypersensitivity induced by low-dose paclitaxel/carboplatin in multiple platinum-treated patients with recurrent ovarian cancer

We report five cases of carboplatin (CBDCA) hypersensitivity after weekly low-dose paclitaxel (60 mg/m2)/CBDCA (area under the concentration curve = 2) therapy in patients with recurrent ovarian cancer receiving multiple platinum-based chemotherapy. Paclitaxel and CBDCA therapy was indicated as second-line chemotherapy in one patient and as third line in four patients with recurrent disease. The range of previously administered total CBDCA was 2582-9589 mg, and the CBDCA area under the concentration curve of the first treatment exhibited appropriate intensity (mean, 1.92 +/- 0.10; range, 1.76-2.10) in all patients. However, one patient exhibited severe hypersensitivity reactions including cardiac arrest and apnea, and another four patients developed eruptions, hypotension, and tachycardia soon after administration of CBDCA. Our report suggested that CBDCA hypersensitivity was correlated with the total dose of previously administered platinum agents and that CBDCA should be excluded in patients who have received multiple platinum-based chemotherapy, even in platinum-sensitive cases, because CBDCA hypersensitivity can occur even with low-dose CBDCA administration.

Carboplatin hypersensitivity induced by low-dose paclitaxel/carboplatin in multiple platinum-treated patients with recurrent ovarian cancer

We report five cases of carboplatin (CBDCA) hypersensitivity after weekly low-dose paclitaxel (60 mg/m2)/CBDCA (area under the concentration curve = 2) therapy in patients with recurrent ovarian cancer receiving multiple platinum-based chemotherapy. Paclitaxel and CBDCA therapy was indicated as second-line chemotherapy in one patient and as third line in four patients with recurrent disease. The range of previously administered total CBDCA was 2582–9589 mg, and the CBDCA area under the concentration curve of the first treatment exhibited appropriate intensity (mean, 1.92 ± 0.10; range, 1.76–2.10) in all patients. However, one patient exhibited severe hypersensitivity reactions including cardiac arrest and apnea, and another four patients developed eruptions, hypotension, and tachycardia soon after administration of CBDCA. Our report suggested that CBDCA hypersensitivity was correlated with the total dose of previously administered platinum agents and that CBDCA should be excluded in patients who have received multiple platinum-based chemotherapy, even in platinum-sensitive cases, because CBDCA hypersensitivity can occur even with low-dose CBDCA administration.

Dysferlin mutations in Japanese Miyoshi myopathy: relationship to phenotype

OBJECTIVE

To study dysferlin gene mutations and genotype-phenotype correlations in Japanese patients with Miyoshi myopathy (MM).

BACKGROUND

MM is an autosomal recessive distal muscular dystrophy that arises from mutations in the dysferlin gene. This gene is also mutated in families with limb girdle muscular dystrophy 2B.

METHODS

The authors examined 25 Japanese patients with MM. Genomic DNA was extracted from the peripheral lymphocytes of the patients. The PCR products of each of 55 exons were screened by single strand conformation polymorphism or direct sequencing from the PCR fragments.

RESULTS

The authors identified 16 different mutations in 20 patients with MM; 10 were novel. Mutations in Japanese patients are distributed along the entire length of the gene.

CONCLUSIONS

Four mutations (C1939G, G3370T, 3746delG, and 4870delT) are relatively more prevalent in this population, accounting for 60% of the mutations in this study. This study revealed that the G3370T mutation was associated with milder forms of MM and the G3510A mutation was associated with a more severe form.

Theoretical study on the excited states of psoralen compounds bonded to a thymine residue

Time-dependent density functional theory calculations have been performed for the excited states of psoralen, 5-methoxypsoralen, and 8-methoxypsoralen in systems and furan and pyrone monoadducts bonded to a thymine residue. The theoretical assignments to ultraviolet (UV) absorption spectra of isolated systems have been performed. The present calculations have clarified that the excitation energies of the first singlet excited (S1) state of monoadducts are blue-shifted compared with the isolated systems. It is shown that, in particular, the S1 excitation energy of the pyrone monoadduct is significantly blue-shifted and, therefore, the pyrone monoadduct is not excited by UV-A light (300-400 nm), which is used in the photochemotherapy.

Basic science and epilepsy: experimental epilepsy surgery

Epilepsy surgery, as is employed for the management of intractable seizures, was performed in animals harboring a seizure focus induced by a local application of kainic acid (KA). Amygdalo-hippocampectomy failed to stop spontaneous seizures in the contralateral hippocampus. Callosotomy inhibited seizure propagation to the contralateral sensori-motor cortex. However, epileptic activity ipsilateral to the focus, including subcortical structures, persisted even after the callosotomy. Multiple subpial transection (MST) around the epileptic cortical focus suppressed the seizure activity of the cortex. However, seizure propagations in subcortical structures remained, even after MST. Nefiracetam (a new nootropic agent) was tested in these models, and its promising effect on the intractable extratemporal epilepsy is reported.

Low-dose mitomycin C, etoposide, and cisplatin for invasive vulvar Paget's disease

We report the effect of low-dose mitomycin C, etoposide, and cisplatin (low-dose MEP) therapy for three patients with invasive vulvar Paget's disease (invasive VPD) who declined radical vulvectomy and skin grafting. One patient achieved a complete response, while the other two showed partial responses (PR) without grade 3 or 4 adverse effects. The two patients with PR were undergone partial vulvectomy and inguinal lymph node dissection. All patients have no sign of recurrence for 10 months after chemotherapy. Our present results suggest that low-dose MEP is an effective and safe chemotherapy for invasive VPD and low-dose MEP may significantly improve postoperative quality of life in patients with invasive VPD by avoiding extensive vulvar resection and skin grafting.

Low-dose mitomycin C, etoposide, and cisplatin for invasive vulvar Paget's disease

Abstract.

Watanabe Y, Hoshiai H, Ueda H, Nakai H, Obata K, Noda K. Low-dose mitomycin C, etoposide, and cisplatin for invasive Paget's disease.

We report the effect of low-dose mitomycin C, etoposide, and cisplatin (low-dose MEP) therapy for three patients with invasive vulvar Paget's disease (invasive VPD) who declined radical vulvectomy and skin grafting. One patient achieved a complete response, while the other two showed partial responses (PR) without grade 3 or 4 adverse effects. The two patients with PR were undergone partial vulvectomy and inguinal lymph node dissection. All patients have no sign of recurrence for 10 months after chemotherapy. Our present results suggest that low-dose MEP is an effective and safe chemotherapy for invasive VPD and low-dose MEP may significantly improve postoperative quality of life in patients with invasive VPD by avoiding extensive vulvar resection and skin grafting.