Near infrared imaging system for preventing blood vision obstruction in endoscopy

Spinal endoscopy procedure is commonly used in the diagnosis and treatment of various health problems and is effective. Bleeding is one of the most common complications of spinal endoscopy procedures. Blood vision obstruction (BVO), that is, obstruction of the endoscopic camera lens caused by the accumulation of blood in the surgical field, is a serious problem in endoscopic procedures. This study presents what we believe to be a new approach to addressing BVO with external multispectral imaging. The study was completed using a BVO simulation model, and the results reveal that this technology can be used to effectively overcome BVO and provide clear images of the anatomy, enabling more effective diagnosis and treatment. This technique may enable improvement of the outcomes of endoscopic procedures and could have far-reaching implications in the field of endoscopy.

Atezolizumab plus bevacizumab versus lenvatinib or sorafenib in non-viral unresectable hepatocellular carcinoma: an international propensity score matching analysis

BACKGROUND

A growing body of evidence suggests that non-viral hepatocellular carcinoma (HCC) might benefit less from immunotherapy.

MATERIALS AND METHODS

We carried out a retrospective analysis of prospectively collected data from consecutive patients with non-viral advanced HCC, treated with atezolizumab plus bevacizumab, lenvatinib, or sorafenib, in 36 centers in 4 countries (Italy, Japan, Republic of Korea, and UK). The primary endpoint was overall survival (OS) with atezolizumab plus bevacizumab versus lenvatinib. Secondary endpoints were progression-free survival (PFS) with atezolizumab plus bevacizumab versus lenvatinib, and OS and PFS with atezolizumab plus bevacizumab versus sorafenib. For the primary and secondary endpoints, we carried out the analysis on the whole population first, and then we divided the cohort into two groups: non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) population and non-NAFLD/NASH population.

RESULTS

One hundred and ninety patients received atezolizumab plus bevacizumab, 569 patients received lenvatinib, and 210 patients received sorafenib. In the whole population, multivariate analysis showed that treatment with lenvatinib was associated with a longer OS [hazard ratio (HR) 0.65; 95% confidence interval (CI) 0.44-0.95; P = 0.0268] and PFS (HR 0.67; 95% CI 0.51-0.86; P = 0.002) compared to atezolizumab plus bevacizumab. In the NAFLD/NASH population, multivariate analysis confirmed that lenvatinib treatment was associated with a longer OS (HR 0.46; 95% CI 0.26-0.84; P = 0.0110) and PFS (HR 0.55; 95% CI 0.38-0.82; P = 0.031) compared to atezolizumab plus bevacizumab. In the subgroup of non-NAFLD/NASH patients, no difference in OS or PFS was observed between patients treated with lenvatinib and those treated with atezolizumab plus bevacizumab. All these results were confirmed following propensity score matching analysis. By comparing patients receiving atezolizumab plus bevacizumab versus sorafenib, no statistically significant difference in survival was observed.

CONCLUSIONS

The present analysis conducted on a large number of advanced non-viral HCC patients showed for the first time that treatment with lenvatinib is associated with a significant survival benefit compared to atezolizumab plus bevacizumab, in particular in patients with NAFLD/NASH-related HCC.

Domain-Specific Cognitive Prosthesis for Face Memory and Recognition

The present study proposes a cognitive prosthesis device for face memory impairment as a proof-of-concept for the domain-specific cognitive prosthesis. Healthy subjects (n = 6) and a patient with poor face memory were enrolled. An acquaintance face recognition test with and without the use of cognitive prosthesis for face memory impairment, face recognition tests, quality of life, neuropsychological assessments, and machine learning performance of the cognitive prosthesis were followed-up throughout four weeks of real-world device use by the patient. The healthy subjects had an accuracy of 92.38 ± 4.41% and reaction time of 1.27 ± 0.12 s in the initial attempt of the acquaintance face recognition test, which changed to 80.48 ± 6.23% (p = 0.06) and 2.11 ± 0.20 s (p < 0.01) with prosthesis use. The patient had an accuracy of 74.29% and a reaction time of 6.65 s, which improved to 94.29% and 3.28 s with prosthesis use. After four weeks, the patient’s unassisted accuracy and reaction time improved to 100% and 1.23 s. Functional MRI study revealed activation of the left superior temporal lobe during face recognition task without prosthesis use and activation of the right precentral motor area with prosthesis use. The prosthesis could improve the patient’s performance by bypassing the brain area inefficient for facial recognition and employing the area more efficiently for the cognitive task.

Nonalcoholic steatohepatitis in hepatocarcinoma: new insights about its prognostic role in patients treated with lenvatinib

BACKGROUND

Hepatocellular carcinoma (HCC) treatment remains a big challenge in the field of oncology. The liver disease (viral or not viral) underlying HCC turned out to be crucial in determining the biologic behavior of the tumor, including its response to treatment. The aim of this analysis was to investigate the role of the etiology of the underlying liver disease in survival outcomes.

PATIENTS AND METHODS

We conducted a multicenter retrospective study on a large cohort of patients treated with lenvatinib as first-line therapy for advanced HCC from both Eastern and Western institutions. Univariate and multivariate analyses were performed.

RESULTS

Among the 1232 lenvatinib-treated HCC patients, 453 (36.8%) were hepatitis C virus positive, 268 hepatitis B virus positive (21.8%), 236 nonalcoholic steatohepatitis (NASH) correlate (19.2%) and 275 had other etiologies (22.3%). The median progression-free survival (mPFS) was 6.2 months [95% confidence interval (CI) 5.9-6.7 months] and the median overall survival (mOS) was 15.8 months (95% CI 14.9-17.2 months). In the univariate analysis for OS NASH-HCC was associated with longer mOS [22.2 versus 15.1 months; hazard ratio (HR) 0.69; 95% CI 0.56-0.85; P = 0.0006]. In the univariate analysis for PFS NASH-HCC was associated with longer mPFS (7.5 versus 6.5 months; HR 0.84; 95% CI 0.71-0.99; P = 0.0436). The multivariate analysis confirmed NASH-HCC (HR 0.64; 95% CI 0.48-0.86; P = 0.0028) as an independent prognostic factor for OS, along with albumin-bilirubin (ALBI) grade, extrahepatic spread, neutrophil-to-lymphocyte ratio, portal vein thrombosis, Eastern Cooperative Oncology Group (ECOG) performance status and alpha-fetoprotein. An interaction test was performed between sorafenib and lenvatinib cohorts and the results highlighted the positive predictive role of NASH in favor of the lenvatinib arm (P = 0.0047).

CONCLUSION

NASH has been identified as an independent prognostic factor in a large cohort of patients with advanced HCC treated with lenvatinib, thereby suggesting the role of the etiology in the selection of patients for tyrosine kinase treatment. If validated, this result could provide new insights useful to improve the management of these patients.

Immune-mediated axonal dysfunction in seropositive and seronegative primary Sjögren's syndrome

OBJECTIVE

The present study investigates the peripheral neuropathy in Primary Sjögren's syndrome (pSS) using the nerve excitability test to further elucidate how peripheral nerves are affected by the autoantibodies.

METHODS

Each patient received clinical evaluation, examination for anti-SSA/Ro and anti-SSB/La antibodies titer, paired motor and sensory nerve excitability test, thermal quantitative sensory test (QST), and nerve conduction study (NCS).

RESULTS

A total of 40 pSS patients wasenrolled. Motor axonal study of the pSS with positive anti-SSA/Ro or anti-SSB/La antibodies (n = 28) was found to have increased stimulus for 50% compound muscle action potential (CMAP) (P < 0.05), increased rheobase (P < 0.01), increased minimum I/V slope (P < 0.01) and hyperpolarizing I/V slope (P < 0.05), increased relative refractory period (RRP, P < 0.001), decreased accommodation of threshold electrotonus toward depolarizing current (P < 0.05), and increased accommodation toward hyperpolarizing current (P < 0.05). Seronegative pSS (n = 10) showed much less prominent motor axonal changes, showing only increased minimum I/V slope (P < 0.05). Sensory axonal study in seropositive pSS patients is found to have increased stimulus for 50% sensory nerve action potential (SNAP) (P < 0.01), decreased latency (P < 0.01), increased RRP (P < 0.01), and increased subexcitability (P < 0.05). Seronegative pSS patients have shown no significant sensory axonal changes. Thermal QST showed more prominent abnormalities in seronegative pSS compared to seropositive pSS.

INTERPRETATION

Anti-SSA/Ro and anti-SSB/La autoantibodies might cause dysfunction in nodal and internodal region of the axon and small nerve fibers; meanwhile, autoreactive antibodies in seronegative pSS mainly affect small nerve fibers. Thus, the underlying pathophysiology for the two types of pSS is different.

Novel Insights into the Pathogenesis of Spinal Sarcopenia and Related Therapeutic Approaches: A Narrative Review

Spinal sarcopenia is a complex and multifactorial disorder associated with a loss of strength, increased frailty, and increased risks of fractures and falls. In addition, spinal sarcopenia has been associated with lumbar spine disorders and osteoporosis, which renders making decisions on treatment modalities difficult. Patients with spinal sarcopenia typically exhibit lower cumulative survival, a higher risk of in-hospital complications, prolonged hospital stays, higher postoperative costs, and higher rates of blood transfusion after thoracolumbar spine surgery. Several studies have focused on the relationships between spinal sarcopenia, appendicular muscle mass, and bone-related problems-such as osteoporotic fractures and low bone mineral density-and malnutrition and vitamin D deficiency. Although several techniques are available for measuring sarcopenia, each of them has its advantages and shortcomings. For treating spinal sarcopenia, nutrition, physical therapy, and medication have been proven to be effective; regenerative therapeutic options seem to be promising owing to their repair and regeneration potential. Therefore, in this narrative review, we summarize the characteristics, detection methodologies, and treatment options for spinal sarcopenia, as well as its role in spinal disorders.

Early sensory neurophysiological changes in prediabetes

AIMS/INTRODUCTION

To elucidate whether axonal changes arise in the prediabetic state and to find a biomarker for early detection of neurophysiological changes.

MATERIALS AND METHODS

We enrolled asymptomatic diabetes patients, as well as prediabetic and normoglycemic individuals to test sensory nerve excitability, and we analyzed those findings and their correlation with clinical profiles.

RESULTS

In nerve excitability tests, superexcitability in the recovery cycle showed increasing changes in the normoglycemic, prediabetes and diabetes cohorts (-19.09 ± 4.56% in normoglycemia, -22.39 ± 3.16% in prediabetes and -23.71 ± 5.15% in diabetes, P = 0.002). Relatively prolonged distal sensory latency was observed in the median nerve (3.12 ± 0.29 ms in normoglycemia, 3.23 ± 0.38 ms in prediabetes and 3.45 ± 0.43 ms in diabetes, P = 0.019). Superexcitability was positively correlated with fasting plasma glucose (r = 0.291, P = 0.009) and glycated hemoglobin (r = 0.331, P = 0.003) in all participants.

CONCLUSIONS

Sensory superexcitability and latencies are the most sensitive parameters for detecting preclinical physiological dysfunction in prediabetes. In addition, changes in favor of superexcitability were positively correlated with glycated hemoglobin for all participants. These results suggest that early axonal changes start in the prediabetic stage, and that the monitoring strategy for polyneuropathy should start as early as prediabetes.

Elucidating Unique Axonal Dysfunction Between Nitrous Oxide Abuse and Vitamin B12 Deficiency

Introduction: Abuse of nitrous oxide (N₂O) has an unusually high lifetime prevalence in developed countries and represents a serious concern worldwide. Myeloneuropathy following the inhalant abuse is commonly attributed to the disturbance of vitamin B12 metabolism, with severe motor deficits are often noted. The present study aims to elucidate its underlying pathophysiology.

Methods: Eighteen patients with N₂O abuse or vitamin B12 deficiency were recruited. Comprehensive central and peripheral neuro-diagnostic tests were performed, including whole spine MRI, and thermal quantitative sensory testing (QST). Specifically, paired motor and sensory nerve excitability tests were performed in order to obtain a complete picture of the sensorimotor axonal damage.

Results: The mean duration of N₂O exposure for the N₂O abuse patients was 17.13 ± 7.23 months. MRI revealed T2 hyperintensity in 87.5% of the N₂O abuse patients and 50% of the vitamin B12 deficiency patients. In N₂O abuse patients, the motor nerve excitability test showed decreased in peak response (7.08 ± 0.87 mV, P = 0.05), increased latency (7.09 ± 0.28 ms, P < 0.01), increased superexcitability (−32.95 ± 1.74%, P < 0.05), and decreased accommodation to depolarizing current [TEd (40–60 ms) 56.53 ± 0.70%, P < 0.05]; the sensory test showed only decreased peak response (30.54 ± 5.98 μV, P < 0.05). Meanwhile, motor test in vitamin B12 deficiency patients showed only decreased accommodation to depolarizing current [TEd (40–60 ms) 55.72 ± 1.60%, P < 0.01]; the sensory test showed decreased peak response (25.86 ± 3.44 μV, P < 0.05) increased superexcitability (−28.58 ± 3.71%, P < 0.001), increased subexcitability (8.31 ± 1.64%, P < 0.05), and decreased accommodation to depolarizing current [TEd (peak) 67.31 ± 3.35%, P < 0.001].

Conclusion: Compared to vitamin B12 deficiency, N₂O abuse patients showed prominent motor superexcitability changes and less prominent sensory superexcitability changes, hinting a unique pathological process different from that of vitamin B12 deficiency. N₂O abuse might cause axonal dysfunction not only by blocking methionine metabolism but also by toxicity affecting the paranodal region.

116 Altered peripheral axonal properties in fibromyalgia

Introduction

Fibromyalgia (FM), a common chronic widespread pain syndrome with neurological symptoms affecting ∼10% of the population worldwide. Whereas small fibre neuropathy is a recognized part of FM, surprisingly little is known about large fibre neuropathy. The present study investigates the sensory and motor axonal properties using novel nerve excitability testing (NET) to seek a better understanding of the pathogenesis of this painful disorder.

Methods

25 FM patients were recruited from the Wan Fang Hospital in Taiwan who fulfilled the American College of Rheumatology diagnostic criteria.1 NCS, pain scores, blood tests and NET were performed in all patients and patients with factors that may confound the results of NET were excluded. Control data were obtained from age and gender-matched healthy controls (HC) who had no neurological deficits or known pain disorders.

Results

The FM group showed an increase in superexcitability (p<0.05), subexcitability (p<0.05) and over-shoot during hyperpolarizing threshold electrotonus (p<0.05) in the sensory excitability profiles in contrast to HC. However, motor nerve excitability profiles showed no significant difference.

Conclusions

Alterations in the sensory axonal parameters can be detected while NCS is normal, these findings are compatible with the concept that the sensory system is mainly involved in the pathogenesis of FM. Results implied probable hypofunction of the paranodal fast K+ channel in the sensory axons, known to be associated with the generation of pain.2 Our study highlights the advantage of NET over NCS, in the early detection of axonal dysfunction and may provide further understandings of future therapeutic treatment.

References

Wolfe F, Clauw DJ, Fitzcharles MA, Goldenberg DL, Hauser W, Katz RS, Mease P, Russell AS, Russell IJ, Winfield JB. Fibromyalgia criteria and severity scales for clinical and epidemiological studies: a modification of the ACR Preliminary Diagnostic Criteria for Fibromyalgia. J Rheumatol 2011;38(6):1113–1122.

Kuwabara S, Misawa S. Pharmacologic intervention in axonal excitability: in vivo assessment of nodal persistent sodium currents in human neuropathies. Curr Mol Pharmacol 2008;1(1):61–67.

Low incidence of hepatitis B virus reactivation and subsequent hepatitis in patients with chronic hepatitis C receiving direct-acting antiviral therapy

To determine the clinical characteristics of hepatitis B virus (HBV) reactivation in patients undergoing interferon-free antihepatitis C virus (HCV) therapy, we examined HBV DNA in 25 HBV co-infected patients and 765 patients with resolved HBV infection during and after treatment with direct-acting antiviral agents (DAAs). Among those with HCV genotype 1, asunaprevir plus daclatasvir was administered to 160 patients, sofosbuvir (SOF) plus ledipasvir to 438 patients and paritaprevir plus ombitasvir and ritonavir to 25 patients. In total, 167 patients with genotype 2 were treated with SOF plus ribavirin. Three patients with an HBV DNA level ≥2000 IU/mL were treated with entecavir before anti-HCV therapy, without reactivation of HBV. In 3 of 22 (12%) HBV surface antigen (HBsAg)-positive patients with an HBV DNA level <2000 IU/mL, the viral load increased during treatment. However, hepatitis flare did not occur in these patients. There was no significant difference in clinical history between patients with and without HBV reactivation. Among 765 patients with resolved HBV infection, HBV reactivation occurred in 1 (0.1%) patient after initial resolution, whose HBV DNA level spontaneously decreased after DAA therapy. We compared anti-HBs titres at baseline with those at post-DAA therapy in 123 patients without HBsAg. There was no significant difference in anti-HBs levels between the two points (P = .79). In conclusion, HBV reactivation was rare in HBsAg-negative patients treated with DAA therapy. Additionally, hepatitis did not occur in HBV-reactivated patients with a baseline HBV DNA level <2000 IU/mL before DAA therapy.

Uncovering sensory axonal dysfunction in asymptomatic type 2 diabetic neuropathy

This study investigated sensory and motor nerve excitability properties to elucidate the development of diabetic neuropathy. A total of 109 type 2 diabetes patients were recruited, and 106 were analyzed. According to neuropathy severity, patients were categorized into G0, G1, and G2+3 groups using the total neuropathy score-reduced (TNSr). Patients in the G0 group were asymptomatic and had a TNSr score of 0. Sensory and motor nerve excitability data from diabetic patients were compared with data from 33 healthy controls. Clinical assessment, nerve conduction studies, and sensory and motor nerve excitability testing data were analyzed to determine axonal dysfunction in diabetic neuropathy. In the G0 group, sensory excitability testing revealed increased stimulus for the 50% sensory nerve action potential (P<0.05), shortened strength-duration time constant (P<0.01), increased superexcitability (P<0.01), decreased subexcitability (P<0.05), decreased accommodation to depolarizing current (P<0.01), and a trend of decreased accommodation to hyperpolarizing current in threshold electrotonus. All the changes progressed into G1 (TNSr 1–8) and G2+3 (TNSr 9–24) groups. In contrast, motor excitability only had significantly increased stimulus for the 50% compound motor nerve action potential (P<0.01) in the G0 group. This study revealed that the development of axonal dysfunction in sensory axons occurred prior to and in a different fashion from motor axons. Additionally, sensory nerve excitability tests can detect axonal dysfunction even in asymptomatic patients. These insights further our understanding of diabetic neuropathy and enable the early detection of sensory axonal abnormalities, which may provide a basis for neuroprotective therapeutic approaches.

Tracking Control of a Miniature Flexible Arm Using Piezoelectric Bimorph Cells

A theoretical and experimental study is presented for the end- point control of a slender flexible arm driven by piezoelectric bimorph cells. A discrete-time formulation is presented for the arm-cell system and applied to the problem of moving the arm so that the tip closely tracks the fluctuation of target. The tip displacement (versus time) is compared with the target fluctuation, and the tip position error is used, together with other estimated system states, as the basis for applying control voltage to the cells. Both simulation and experimental results show that the PID control using the piezoelectric cells as the actuators is sufficient to make the arm tip follow the fluctuation of target precisely.

Sensory axonal dysfunction in cervical radiculopathy

OBJECTIVE

The aim of this study was to evaluate changes in sensory axonal excitability in the distal nerve in patients with cervical radiculopathy.

METHODS

The patients were classified by the findings of cervical MRI into two subgroups: 22 patients with C6/7 root compression and 25 patients with cervical cord and root compression above/at C6/7. Patients were investigated using conventional nerve conduction studies (NCS) and nerve excitability testing. Sensory nerve excitability testing was undertaken with stimulation at the wrist and recording from digit II (dermatome C6/7). The results were compared with healthy controls. Both preoperative and postoperative tests were performed if the patient underwent surgery.

RESULTS

Sensory axonal excitability was significantly different in both cohorts compared with healthy controls, including prolonged strength-duration time constant, reduced S2 accommodation, increased threshold electrotonus hyperpolarisation (TEh (90-100 ms)), and increased superexcitability. The changes in these excitability indices are compatible with axonal membrane hyperpolarisation. In five patients who underwent surgery, the postoperative sensory excitability was tested after 1 week, and showed significant changes in TE (TEh (90-100 ms) and TEh slope, p<0.05) between presurgery and postsurgery.

CONCLUSIONS

The present study demonstrated distal nerve axonal hyperpolarisation in patients with cervical radiculopathy. These findings suggest that the hyperpolarised pattern might be due to Na(+)-K(+) ATPase overactivation induced by proximal ischaemia, or could reflect the remyelinating process. Distal sensory axons were hyperpolarised even though there were no changes in NCS, suggesting that nerve excitability testing may be more sensitive to clinical symptoms than NCS in patients with cervical radiculopathy.

Early identification of 'acute-onset' chronic inflammatory demyelinating polyneuropathy

Distinguishing patients with acute-onset chronic inflammatory demyelinating polyneuropathy from acute inflammatory demyelinating polyneuropathy prior to relapse is often challenging at the onset of their clinical presentation. In the present study, nerve excitability tests were used in conjunction with the clinical phenotype and disease staging, to differentiate between patients with acute-onset chronic inflammatory demyelinating polyneuropathy and patients with acute inflammatory demyelinating polyneuropathy at an early stage, with the aim to better guide treatment. Clinical assessment, staging and nerve excitability tests were undertaken on patients initially fulfilling the diagnostic criteria of acute inflammatory demyelinating polyneuropathy soon after symptom onset and their initial presentation. Patients were subsequently followed up for minimum of 12 months to determine if their clinical presentations were more consistent with acute-onset chronic inflammatory demyelinating polyneuropathy. Clinical severity as evaluated by Medical Research Council sum score and Hughes functional grading scale were not significantly different between the two cohorts. There was no difference between the time of onset of initial symptoms and nerve excitability test assessment between the two cohorts nor were there significant differences in conventional nerve conduction study parameters. However, nerve excitability test profiles obtained from patients with acute inflammatory demyelinating polyneuropathy demonstrated abnormalities in the recovery cycle of excitability, including significantly reduced superexcitability (P < 0.001) and prolonged relative refractory period (P < 0.01), without changes in threshold electrotonus. In contrast, in patients with acute-onset chronic inflammatory demyelinating polyneuropathy, a different pattern occurred with the recovery cycle shifted downward (increased superexcitability, P < 0.05; decreased subexcitability, P < 0.05) and increased threshold change in threshold electrotonus in both hyperpolarizing and depolarizing directions [depolarizing threshold electrotonus (90-100 ms) P < 0.005, hyperpolarizing threshold electrotonus (10-20 ms), P < 0.01, hyperpolarizing threshold electrotonus (90-100 ms), P < 0.05], perhaps suggesting early hyperpolarization. In addition, using excitability parameters superexcitability, subexcitability and hyperpolarizing threshold electrotonus (10-20 ms), the patients with acute inflammatory demyelinating polyneuropathy and acute-onset chronic inflammatory demyelinating polyneuropathy could be clearly separated into two non-overlapping groups. Studies of nerve excitability may be able to differentiate acute from acute-onset chronic inflammatory demyelinating polyneuropathy at an early stage. Characteristic nerve excitability parameter changes occur in early acute-onset chronic inflammatory demyelinating polyneuropathy, to match the clinical phenotype. Importantly, this pattern of change was strikingly different to that shown by patients with acute inflammatory demyelinating polyneuropathy, suggesting that nerve excitability techniques may be useful in distinguishing acute-onset chronic inflammatory demyelinating polyneuropathy from acute inflammatory demyelinating polyneuropathy at the initial stage.

Updates on current advances in gene therapy

Gene therapy is the attempt to treat diseases by means of genetic manipulation. Numerous challenges remain to be overcome before it becomes available as a safe and effective treatment option. Retroviruses and adenoviruses are among the most commonly used viral vectors in trials. The retrovirus introduces the gene it carries into the target cell genome while the adenovirus introduces the gene into the target cell nucleus without incorporating it into the target cell genome. Other viral vectors such as adeno-associated viruses, pseudotyped viruses and herpes simplex viruses, are also gaining popularity. Proposed non-viral methods for gene transfer include physical methods and the employment of chemical vectors (lipoplexes, polyplexes and inorganic nanoparticles). Recent studies have investigated potential applications of gene therapy in correcting genetic diseases, treating malignant disorders and for treatment of other diseases. Trials on gene therapy for SCID and Leber's congenital amaurosis have achieved considerable success, but the widely publicized adverse reaction in X-linked SCID patient receiving gene therapy raised concerns for safety profile of gene therapy. For that, several methods of improving safety and efficacy of gene therapy have been proposed. At present, the three main gene therapy strategies for treatment of cancer are application to oncolytic viruses, suicide-gene therapy and gene-based immunotherapy. Gendicine, the first approved anticancer drugs based on the use of gene therapy principle, is based on the use of oncolytic viruses. More evidence for wider clinical applications of gene therapy are expected as more gene therapy studies progress from the preclinical phase to clinical trial.

Recent progressions in stem cell research: breakthroughs achieved and challenges faced

Stem cell studies have been conducted to study characteristics of stem cells, to develop better techniques for patient-specific stem cell lines generation, and to explore the therapeutic potential of stem cells. Techniques that enable efficient generation of new stem cell lines would facilitate research and allow generation of patient-specific stem cell lines for transplantation therapy. Somatic-Cell Nuclear Transfer (SCNT), which involves injection of donor cell nucleus into enucleated ovum, is the standard technique for new embryonic stem (ES) cell lines generation; presently its efficiency is low. A newer technique, pluripotent stem cell induction, reprograms somatic cells into induced pluripotent stem (iPS) cells by introducing certain factors into somatic cells. While certain adult stem cell treatments have been investigated on human participants, most ES cell or iPS cell treatments were still experimented on animal models. Recently, therapeutic potential of stem cell for several disorders was demonstrated. Researchers demonstrated stem cell's potential for treating hematologic disorders by correcting sickle cell anemia in rat model with iPS cells. Its potential role in treating cardiovascular disorder was demonstrated as injection of damaged rat heart with human ES cells derived cardiomyocyte plus "prosurvival" cocktail improved heart function. It might also treat nervous system disorders; injected into brain, ES cells derived neurons replace some loss cells in stroke rats and iPS cells derived neurons improved Parkinsonian syndrome in rats. Progress was also seen in other aspects of regenerative medicine. To overcome controversies caused by embryo destruction for obtaining ES cells, single blastomer stem cell derivation, Cdx2-inactivation, and parthenogenesis were proposed. All ES cell, iPS cell, and adult stem cell research should be continued with support from all sides.

Antibodies targeting the calcium binding skeletal muscle protein calsequestrin are specific markers of ophthalmopathy and sensitive indicators of ocular myopathy in patients with Graves' disease

We have identified several eye muscle antigens and studied the significance of the corresponding serum autoantibodies in patients with Graves' disease. Of these antigens, only calsequestrin is expressed more in eye muscle than other skeletal muscles, which could explain at least partly the specific involvement of eye muscle in patients with Graves' disease. Earlier, we found a modest relationship between anti-calsequestrin antibodies and ophthalmopathy, but in that study we used calsequestrin prepared from rabbit heart muscle and measured antibodies by immunoblotting. We have reinvestigated the prevalences of anti-calsequestrin antibodies in larger groups of well-characterized patients with thyroid autoimmunity with and without ophthalmopathy and control patients and healthy subjects, using standard enzyme-linked immunosorbent assay incorporating highly purified rabbit skeletal muscle calsequestrin, which has a 97% homology with human calsequestrin, as antigen. Anti-calsequestrin antibodies were detected in 78% of patients with active congestive ophthalmopathy, in 92% of those with active inflammation and eye muscle involvement, but in only 22% of patients with chronic, 'burnt out' disease. Tests were also positive in 5% of patients with Graves' hyperthyroidism without evident ophthalmopathy (two patients) and one patient with 'watery eyes' but no other clear signs of congestive ophthalmopathy and IgA nephropathy and no known thyroid disease, but in no patient with Hashimoto's thyroiditis, toxic nodular goitre, non-toxic multi-nodular goitre or diabetes, or age- and sex-matched healthy subjects. In serial studies of all 11 patients with Graves' hyperthyroidism who had active ophthalmopathy at the time of the first clinic visit, or developed eye signs during the first 6 months, and positive anti-calsequestrin antibodies in at least one sample, anti-calsequestrin antibodies correlated with the onset of ocular myopathy in six patients. Antibodies targeting calsequestrin appear to be specific markers for ophthalmopathy and sensitive indicators of the ocular myopathy subtype of ophthalmopathy in patients with thyroid autoimmunity. However, these results must be considered preliminary until a large prospective study of patients with newly diagnosed Graves' hyperthyroidism, in which serum levels of calsequestrin antibodies are correlated with clinical changes and orbital eye muscle and connective tissue/fat volumes, has been carried out.

Spontaneous lymphocyt ic thyroiditis in interferon regulatory factor-1 deficient non-obese diabetic mice

Interferon regulatory factor-1 (IRF-1) is a transcription factor involved in interferon-mediated immune reaction, CD8+ T cell differentiation and development of T helper 1 immune reaction. We have recently demonstrated that IRF-1 is pivotal in iodine-induced lymphocytic thyroiditis (LT) in non-obese diabetic (NOD) mice. However, it remains unclear whether the mechanism involved in spontaneous LT is identical with iodine-induced LT in NOD mice. To determine the role of IRF-1 in spontaneous LT, we used IRF-1 deficient NOD mice as well as IRF-1 +/+ and +/- mice which were free from treatments for LT induction, and LT was evaluated at 24 weeks of age. IRF-1 +/+, +/- and -/- mice developed LT spontaneously, and there were no differences among the 3 IRF-1 genotypes in the incidence and severity of LT. Whereas both CD4+ and CD8+ T cells were present in the diseased thyroid of IRF-1 +/+ mice, CD8+ T cells were absent in the thyroid of IRF-1 -/- mice. MHC class II antigen expression was induced in the inflamed thyroid of IRF-1 -/- mice comparable to IRF-1 +/+ mice. There was a selective reduction in the number of CD8+ T cells in the spleen of IRF-1 -/- mice. IFNgamma production, but not IL-10, by concanavalin A-stimulated splenocytes was significantly reduced in IRF-1 deficient mice. These results suggest that IRF-1 plays only a minor role in spontaneous LT in NOD mice and, furthermore, the mechanism involved in spontaneous LT is different from that of iodine-induced LT in NOD mice.

Double-stranded RNA-induced interferon regulatory factor-1 gene expression in FRTL-5 rat thyroid cells

Double-stranded RNA (dsRNA) plays a role in the regulation of cell growth and apoptosis as well as in the cellular antiviral responses. However, it remains unknown if dsRNA-activated signaling systems are functional in the thyroid. Here we report the presence of the dsRNA-dependent protein kinase (PKR) in FRTL-5 rat thyroid cells. In poly(I)-poly(C) (pIC)-stimulated cells, activation of nuclear factor-kappa B (NF kappa B) binding was clearly induced. Incubation of FRTL-5 cells with pIC resulted in a marked increase in interferon regulatory factor-1 (IRF-1) mRNA and phosphorylated signal transducer and activator of transcription-1 (STAT1) levels. Addition of pIC to cells led to type I interferon (IFN) gene expression, especially IFN beta, which can induce STAT1 phosphorylation, suggesting that dsRNA indirectly induced STAT1 phosphorylation through expression of type I IFN. Thus, our results suggest that the dsRNA-activated signaling pathway may be involved in the regulation of IFN-inducible genes in the thyroid.

A model of echolocation of multiple targets in 3D space from a single emission

Bats, using frequency-modulated echolocation sounds, can capture a moving target in real 3D space. The process by which they are able to accomplish this, however, is not completely understood. This work offers and analyzes a model for description of one mechanism that may play a role in the echolocation process of real bats. This mechanism allows for the localization of targets in 3D space from the echoes produced by a single emission. It is impossible to locate multiple targets in 3D space by using only the delay time between an emission and the resulting echoes received at two points (i.e., two ears). To locate multiple targets in 3D space requires directional information for each target. The frequency of the spectral notch, which is the frequency corresponding to the minimum of the external ear's transfer function, provides a crucial cue for directional localization. The spectrum of the echoes from nearly equidistant targets includes spectral components of both the interference between the echoes and the interference resulting from the physical process of reception at the external ear. Thus, in order to extract the spectral component associated with the external ear, this component must first be distinguished from the spectral components associated with the interference of echoes from nearly equidistant targets. In the model presented, a computation that consists of the deconvolution of the spectrum is used to extract the external-ear-dependent component in the time domain. This model describes one mechanism that can be used to locate multiple targets in 3D space.

Learning to perceive the world as articulated: an approach for hierarchical learning in sensory-motor systems

This paper describes how agents can learn an internal model of the world structurally by focusing on the problem of behavior-based articulation. We develop an on-line learning scheme-the so-called mixture of recurrent neural net (RNN) experts-in which a set of RNN modules become self-organized as experts on multiple levels, in order to account for the different categories of sensory-motor flow which the robot experiences. Autonomous switching of activated modules in the lower level actually represents the articulation of the sensory-motor flow. In the meantime, a set of RNNs in the higher level competes to learn the sequences of module switching in the lower level, by which articulation at a further, more abstract level can be achieved. The proposed scheme was examined through simulation experiments involving the navigation learning problem. Our dynamical system analysis clarified the mechanism of the articulation. The possible correspondence between the articulation mechanism and the attention switching mechanism in thalamo-cortical loops is also discussed.

Measurement of red blood cell zinc concentration with Zn-test kit: discrimination between hyperthyroid Graves' disease and transient thyrotoxicosis

We have previously reported in patients with hyperthyroidism that the red blood cell (RBC) zinc (Zn) concentration reflects the mean thyroid hormone concentration over the preceding months. In the present study, the concentration of RBC Zn was measured by a simple and easy method with a Zn-test Wako kit. Within-run and between-run precision were 1.4% and 1.3%, respectively. The relationship between RBC concentration and dilution was linear. The average recovery was 103%. A good correlation (r=0.97) was obtained between this method and atomic absorption spectrophotometry. The mean concentration of RBC Zn in 39 euthyroid controls was 12.6 +/- 1.3 mg/l, ranging from 10.4 to 15.1 mg/l. The RBC Zn concentrations in 38 patients with Graves' disease, in 10 patients with silent thyroiditis and in 3 patients with gestational thyrotoxicosis were 7.3 +/- 1.6 (3.2-9.8), 12.0 +/- 1.6 (9.5-14.2) and 11.8 +/- 1.7 (10.5-13.7) mg/l, respectively. The concentration of RBC Zn was able to differentiate hyperthyroid Graves' disease from transient thyrotoxicosis except in 1 case and was a better index than TSH-binding inhibitory immunoglobulin. These results indicate that measuring RBC Zn with the Zinc-test Wako kit is very useful in differentiating hyperthyroid Graves' disease from transient thyrotoxicosis.

Hyperthyroid Graves' disease and primary hypothyroidism caused by TSH receptor antibodies in monozygotic twins: case reports

A 33-year-old woman with signs and symptoms of hypothyroidism, including increased thyroid stimulating blocking antibody (TSBAb) activity, was referred for treatment by her local physician. Her monozygote twin was treated for hyperthyroid Graves' disease 10 years earlier. This case of hyperthyroidism and hypothyroidism in identical twins suggests the involvement of environmental factors in the pathogenesis of autoimmune thyroid diseases.

Role of thyroid-stimulating blocking antibody in patients who developed hypothyroidism within one year after 131I treatment for Graves' disease

OBJECTIVE

We recently reported that thyroid-stimulating blocking antibody (TSBAb) may not contribute to the development of hypothyroidism more than six years after 131I treatment. In the present study, we attempted to determine whether hypothyroidism that develops within a shorter period of time following 131I therapy is associated with TSBAb.

DESIGN

Retrospective study.

PATIENTS

Sera were obtained from 8 patients who developed hypothyroidism within 6 months after 131I therapy (Group 1), 8 patients who became euthyroid one year after 131I therapy (Group 2), and 7 patients who developed transient hypothyroidism (Group 3).

MEASUREMENTS

Thyroid stimulating antibody (TSAb) activity was measured as the amount of cyclic adenosine monophosphate (cAMP) produced by cultured FRTL-5 cells, and TSBAb activity as the inhibition of cAMP produced in response to 100 mU/l bovine TSH.

RESULTS

At about 3 months after 131I treatment, TSAb activity increased significantly in Groups 2 and 3, but did not change in Group 1. In contrast, TSBAb activity in Group 1 increased significantly and was positive in 6 patients at that time. At 12-18 months after 131I treatment, TSBAb activity tended to decrease and remained positive in 3 patients but became negative in 3 patients. It did not change in the patients in Groups 2 and 3. The patients in Group 1 were treated with levothyroxine, 75-125 micrograms/day. Levothyroxine was discontinued in the 3 patients whose TSBAb activity disappeared. Two of them remained euthyroid, and 1 became hypothyroid.

CONCLUSION

Results indicate that the hypothyroidism that develops within a short time after 131I treatment may be caused by TSBAb activity. Thyroid function may be recovered when TSBAb activity disappears.

Effects of ethanol on the levels of brain 6R-L-erythro-5, 6, 7, 8-tetrahydrobiopterin in the inbred strains of mice. DBA/2J, C3H/HeJ and C57BL/6J with different alcohol preferences

6R-L-erythro-5, 6, 7, 8-tetrahydrobiopterin (6R-BH4) is a coenzyme for tyrosine, tryptophan and phenylalanine hydroxylases, the former two of which are the initial and the rate-limiting enzymes in the biosynthesis of the catecholamines and serotonin, respectively. The present study was designed to determine the changes in concentrations of 6R-BH4 in striatum and midbrain of the inbred strains of mice, DBA/2J, C3H/HeJ and C57BL/6J, with different genetically determined alcohol preferences, following the injection of ethanol (EtOH). The intraperitoneal administration of EtOH (0, 1, 2 and 4 g/kg) significantly and dose-dependently reduced the levels of striatal and midbrain 6R-BH4 in DBA/2J mice with the lowest alcohol preference, and EtOH (4 g/kg, i.p.) reduced the level of striatal 6R-BH4 in C3H/HeJ with medium alcohol preference. Following the administration of EtOH (4 g/kg, i.p.), brain 6R-BH4 levels in C57BL/6J mice with high alcohol preference were lowered compared with the control group, but the difference did not reach statistic significance. EtOH has a tendency to reduce the brain 6R-BH4 levels in mice with lower alcohol preference or higher sensitivity to EtOH. Based on these findings, it was proposed that differences in alcohol drinking behavior in the inbred strains of mice was influenced by brain 6R-BH4.

Effects of ion channel blockers on rapid postmortem changes in extracellular dopamine and serotonin levels in the rat nucleus accumbens

In the present study, we used in vivo brain microdialysis to examine the effects of ion channel blockers tetrodotoxin (TTX), EGTA-free Ca2+ and verapamil on rapid postmortem changes in extracellular levels of dopamine (DA), serotonin (5-HT) and their metabolites dihydroxyphenylacetic acid (DOPAC) and 5-hydroxyindoleacetic acid (5-HIAA) in the ACC of freely moving rats. Extracellular ACC DA levels decreased following the perfusion of the three ion channel blockers in freely moving rats, and then, at death by cervical dislocation, maximum respective 220-, 60- and 90-fold increases were observed in the extracellular output of DA in animals treated with EGTA, verapamil and TTX, respectively. Also, ACC 5-HT decreased following perfusion with the three blockers in the freely moving rats, and then maximum increases of 80-, 30- and 45-fold in the extracellular output of 5-HT were observed at death in animals treated with EGTA, verapamil and TTX, respectively, compared to the baseline. Cervical dislocation-induced rapid postmortem changes were inhibited markedly by perfusion with CSF containing the CA2+ entry blocker verapamil. These observations suggested that rapid postmortem changes in ACC DA and 5-HT release were associated with the action of calcium ion channels and/or voltage gated channels in the CNS.

Possibility of 5-HT3 receptor involvement in alcohol dependence: a microdialysis study of nucleus accumbens dopamine and serotonin release in rats with chronic alcohol consumption

The present study was performed to examine the involvement of serotonin-3 (5-HT3) receptors in the rat nucleus accumbens (ACC) in alcohol dependence. In alcohol-treated rats, perfusion of 40 mM K+ and 100 mM ethanol (EtOH) through the microdialysis probe increased the extracellular levels of ACC dopamine (DA), compared with controls. Perfusion of the serotonin (5-HT) uptake inhibitor sertlarine enhanced the extracellular levels of ACC 5-HT in both groups. Increased 5-HT availability in the synaptic clefts on the ACC further activated ACC DA release in the alcohol-treated rats, in comparison with controls. In the final experiments, perfusion of the 5.0 microM 5-HT3 receptor agonist 2-methyl-5-HT (2-Me-5-HT) through the microdialysis probe enhanced the extracellular levels of ACC DA. Magnitude of 2-Me-5-HT-induced DA release was significantly higher in alcohol-treated rats than in controls. On the other hand, 40 mM K(+)- and 100 mM EtOH-induced extracellular 5-HT release in alcohol-treated rats were markedly inhibited. These results show that (1) chronic alcohol intake increases the sensitivity of 5-HT3 receptors, (2) 5-HT3 receptors regulate DA release in the ACC, (3) the dopaminergic neuronal systems associated with 5-HT3 ionophore in the ACC were upregulated after chronic alcohol exposure, and (4) chronic alcohol intake desensitizes the serotonergic neuronal systems in rat ACC. These findings suggest that neurochemical functions of 5-HT3 receptors in regulating DA release in the ACC after alcohol exposure compensate for the dysfunction of serotonergic activity to restore the original properties in processing alcohol tolerance and that the development of alcohol dependence may be mediated by ACC 5-HT3 receptors.

Increased regional systolic myocardial stiffness of the left ventricle during coronary artery occlusion in a dog: analysis of the finite element model

(1) We measured the instantaneous systolic transfer function of an isolated canine left ventricle (LV) before and after the ligation of the left anterior descending coronary artery (LAD). The instantaneous transfer function before the ligation of the LAD showed a resonance curve whose peak frequency was 30 to 70 Hz. On the other hand, the transfer function 40 min after the ligation of the LAD showed a divided peak in the resonance curve. (2) We constructed a finite element model of a thick-walled spherical shell with a non-uniform structure. In this model, the myocardial elasticity and viscosity of the ischemic region are different from those of non-ischemic regions. One can calculate the theoretical transfer function using modal analysis and also estimate the elasticity and the viscous coefficient of both non-ischemic and ischemic myocardium by fitting the theoretical transfer function to the experimental one. (3) The estimated elasticity of the ischemic myocardium was three to five times larger than that of the non-ischemic myocardium. The estimated viscous coefficient of the ischemic myocardium was about half that of the non-ischemic myocardium. These results showed that ischemia alters the viscoelastic properties of the myocardium during systole as well as during diastole.

Simulation study on heart failure: effects of contractility on cardiac function

Using the model proposed by Beyar and Sideman, the effect of maximum isometric active stress at optimal sarcomere length (sigma 0) on left ventricular (LV) function was examined. Comparing the results of calculated LV function with those of reported experiments, sigma 0 was shown to be a potential indicator of myocardial contractility, and the model of Beyar and Sideman successfully predicted LV function with various myocardial contractilities. The LVP compensation curve, which describes the relationship between sigma 0 and maximum LV pressure, was then hypothesized. The combination of the Beyar-Sideman model and the LVP compensation curve enabled the prediction and approximation of the actual process of deterioration in heart failure. These models represent a step towards a fundamentally new concept in the current clinical situation of compensated heart failure and also in evaluating the process of heart failure.

Simulation study on the effect of external vibration on left ventricular function: potential indicator of LV tolerance to the sudden reduction of myocardial contractility

In a previous study the authors reported that external mechanical vibration applied to the left ventricular (LV) epicardium induces contractility-dependent depression in LV pressure, stroke volume and stroke work. It was suggested that this depression may be caused by the direct effect of external vibration on contractile protein. In another paper in this issue, it is proved that LV function with various myocardial contractilities and the actual process of deterioration in heart failure are well simulated in the model proposed by Beyar and Sideman, after some modifications have been made. In the study reported here it is assumed that an external mechanical vibration induces sudden reduction in myocardial active stress in the model of Beyar and Sideman; in this way the contractility-dependent effect of external vibration on LV function has been simulated. The results of this simulation support the suggestion that external mechanical vibration directly affects contractile protein and reduces LV function, and it is further suggested that the reduction of LV function induced by external vibration reflects the reserve or tolerance capacity of LV to a sudden reduction of myocardial contractility.

Estimation of left ventricular myocardial elasticity and viscosity by a thick-walled spherical model

The authors measured the transfer function (TF) of the left ventricle (LV) in an isolated canine preparation. Here TF indicates the ratio of induced vibration in LV to input vibration when an external mechanical oscillation is applied. TF had a single peak the frequency of which changed from 40 Hz to 80 Hz when LV pressure (LVP) increased from 6 mm Hg to 96 mm Hg. A mathematical model was formulated to estimate the viscoelasticity of the spherical shell. This model was constructed of the material points, elastic components which connected all the material points, and viscous components placed in series with elastic components. Theoretical TF can be computed if the viscoelastic values are given. The value of viscoelasticity at which the theoretical TF best fitted the experimental TF was considered to be the viscoelasticity of the model. The validity of this approach was verified using a silicone spherical shell. The estimated myocardial elasticity was 40 kPa when LVP was 6 mm Hg, 160-170 kPa when LVP was 96 mm Hg and was approximately proportional to LVP, whereas viscosity showed small change. The inclination of elasticity was consistent with previous reports. These results proved that myocardial elasticity can be estimated by analysing the transfer function of the left ventricle.

[Microdensitometric study of maturation and fragility of the bone in male patients with cerebral palsy--the effect of long-term administration of 1 alpha-hydroxy vitamin D3 and the value of osteocalcin as a marker of bony growth]

1) We studied bony maturation and fragility in 48 male patients (4-28 years old) with cerebral palsy. They were divided into three groups; group A (drug free, mild motor handicapped), 10 cases, group B (anticonvulsants administrated, mild motor handicapped), 20 cases, group C (anticonvulsants administrated, severe motor handicapped) 18 cases. The indicator of bone mineral content (sigma GS/D) and metacarpal index (MCI) were analyzed by microdensitometric method. A positive correlation between age and sigma GS/D was detected in all groups but a positive correlation between age and MCI was found only in the group B. There was little difference in sigma GS/D and MIC between group A and group B, but those of group C were significantly decreased. These results suggest that increase of bone mineral is related with aging but metacarpal growth is variable, and a lack of daily activity has greater adverse effect on bony metabolism than administration of anticonvulsants. 2) The alterative rates of sigma GS/D (delta sigma GS/D/sigma GS/D/year) and MCI (delta MCI/MCI/year) after 1 alpha-hydroxy vitamin D3 (D3) treatment for 3 years or more were examined in 17 patients with bony atrophy, as compared with normal controls. The alterative rates of sigma GS/D and MCI were elevated in younger patients with D3 treatment but those were decreased in adult patients. Treatment with D3 remarkably increased bony growth in children. 3) In 37 patients, osteocalcin (OC) was measured by radioimmunoassay. OC was elevated in younger patients who were treated with D3.(ABSTRACT TRUNCATED AT 250 WORDS)

[Pituitary reserve of growth hormone in adolescent patients with cerebral palsy and mental retardation]

The pituitary reserve of growth hormone (GH) was studied in 11 severely handicapped boys (14 approximately 18 years old) with mental retardation and cerebral palsy (CP); athetotic type 4 cases, and spastic type 7 cases. Serum GH was determined before and after intravenous injection of 1 ng/kg growth hormone releasing factor (GRF) or oral administration of 0.1 mg/m2 clonidine. The athetotic type patients showed low somatomedin C (Sm C) concentrations (0.31 +/- 0.11 U/ml), poor responses to clonidine, and good responses to GRF. The spastic type patients showed subnormal responses to GRF although their Sm C was normal (0.91 +/- 0.43 U/ml). Clinically, the stature was small, and the puberty was delayed in the former. The levels of plasma testosterone were significantly lower than those in the latter. It is concluded that athetotic type CP was associated with hypothalamic GRF deficiency and spastic type CP was associated with reduced pituitary reserve of GH.