Compliance with new drug use and the effect of discrepant drug susceptibility testing on MDR/RR-TB treatment

BACKGROUND: Following the WHO???s announcement in 2018, the use of new drugs was recommended for all patients with multidrug-resistant TB (MDR-TB) in Korea. This study aimed to evaluate adherence to new anti-TB drug regimens and implementation of molecular drug susceptibility testing (mDST) in Korea.METHODS: Nationwide, 560 patients were reported as having MDR-TB in 2021. The implementation of mDST and new anti-TB drug use were analysed. The discrepancy between mDST and phenotypic DST (pDST) results and their implications on the use of new anti-TB drugs were also analysed. The use of novel anti-TB drugs has been approved by the National TB Expert Committee.RESULTS: The non-adherence rate in MDR-TB patients was 14.3%. The mDST implementation rate was 96.1%. Of the 459 patients who underwent both mDST and pDST, the discordance rate for rifampicin (RIF) resistance was 22.6% (n = 104), of which 72.1% (n = 75) were resistant on mDST but susceptible on pDST. The discrepancy in mDST and pDST results related to RIF resistance was found to be the main cause of non-adherence to new drug regimen.CONCLUSION: Comprehensive training on how to interpret conflicting results between mDST and pDST could enhance the utilisation of new drugs in the treatment of MDR/RIF-resistant TB.

Hemorrhagic morbidity in nulliparous patients with placenta previa without placenta accrete spectrum disorders

Background

Placental adhesion spectrum (PAS) is a disease in which the trophoblast invades the myometrium, and is a well-known high-risk condition associated with placental previa.

Aim

The morbidity of nulliparous women with placenta previa without PAS disorders is unknown.

Patients and Methods

The data from nulliparous women who underwent cesarean delivery were collected retrospectively. The women were dichotomized into malpresentation (MP) and placenta previa groups. The placenta previa group was categorized into previa (PS) and low-lying (LL) groups. When the placenta covers the internal cervical os, it is called placenta previa, when the placenta is near the cervical os, it is called the low-lying placenta. Their maternal hemorrhagic morbidity and neonatal outcomes were analyzed and adjusted using multivariate analysis based on univariate analysis.

Results

A total of 1269 women were enrolled: 781 women in the MP group and 488 women in the PP-LL group. Regarding packed red blood cell transfusion, PP and LL had adjusted odds ratio (aOR) of 14.7 (95% confidence interval (CI): 6.6 - 32.5), and 11.3 (95% CI: 4.9 - 26) during admission, and 51.2 (95% CI: 22.1 - 122.7) and 10.3 (95% CI: 3.9 - 26.6) during operation, respectively. For intensive care unit admission, PS and LL had aOR of 15.9 (95% CI: 6.5 - 39.1) and 3.5 (95% CI: 1.1 - 10.9), respectively. No women had cesarean hysterectomy, major surgical complications, or maternal death.

Conclusion

Despite placenta previa without PAS disorders, maternal hemorrhagic morbidity was significantly increased. Thus, our results highlight the need for resources for those women with evidence of placenta previa including a low-lying placenta, even if those women do not meet PAS disorder criteria. In addition, placenta previa without PAS disorder was not associated with critical maternal complications.

Treatment outcomes of multidrug-resistant TB with selective use of new drugs

SETTING: This was a nationwide cohort study.OBJECTIVE: To assess the treatment outcomes in patients with multidrug-resistant TB (MDR-TB) who underwent treatment guided by a national TB expert review committee in South Korea.DESIGN: We enrolled all patients with MDR-TB submitted for approval for the use of new TB drugs, including bedaquiline and delamanid, from 2016 to 2019. Patients were classified into two groups: those on new TB drugs and those not on new TB drugs. We compared the final treatment outcomes between the groups and analysed the prognostic factors.RESULTS: Of a total of 785 patients, respectively 754 (96.1%) and 31 (3.9%) were classified into the "new TB drugs" group and "no new TB drugs" group. The new TB drugs group had a higher acid-fast bacilli smear positivity rate and higher resistance rate to second-line injectable drugs or fluoroquinolones. Of all the patients, 97.8% achieved culture conversion (97.7% vs. 100%), and 80.4% achieved treatment success (80.2% vs. 86.7%); there was no difference between the two groups.CONCLUSIONS: New drugs are currently recommended for use in all MDR-TB treatment regimens, and the use of new drugs, as determined by an expert committee, in mainly quinolone-susceptible MDR-TB, did not compromise the treatment success rate.

An in silico method to assess antibody fragment polyreactivity

Antibodies are essential biological research tools and important therapeutic agents, but some exhibit non-specific binding to off-target proteins and other biomolecules. Such polyreactive antibodies compromise screening pipelines, lead to incorrect and irreproducible experimental results, and are generally intractable for clinical development. Here, we design a set of experiments using a diverse naïve synthetic camelid antibody fragment (nanobody) library to enable machine learning models to accurately assess polyreactivity from protein sequence (AUC > 0.8). Moreover, our models provide quantitative scoring metrics that predict the effect of amino acid substitutions on polyreactivity. We experimentally test our models' performance on three independent nanobody scaffolds, where over 90% of predicted substitutions successfully reduced polyreactivity. Importantly, the models allow us to diminish the polyreactivity of an angiotensin II type I receptor antagonist nanobody, without compromising its functional properties. We provide a companion web-server that offers a straightforward means of predicting polyreactivity and polyreactivity-reducing mutations for any given nanobody sequence.

Rapid generation of potent antibodies by autonomous hypermutation in yeast

The predominant approach for antibody generation remains animal immunization, which can yield exceptionally selective and potent antibody clones owing to the powerful evolutionary process of somatic hypermutation. However, animal immunization is inherently slow, not always accessible and poorly compatible with many antigens. Here, we describe 'autonomous hypermutation yeast surface display' (AHEAD), a synthetic recombinant antibody generation technology that imitates somatic hypermutation inside engineered yeast. By encoding antibody fragments on an error-prone orthogonal DNA replication system, surface-displayed antibody repertoires continuously mutate through simple cycles of yeast culturing and enrichment for antigen binding to produce high-affinity clones in as little as two weeks. We applied AHEAD to generate potent nanobodies against the SARS-CoV-2 S glycoprotein, a G-protein-coupled receptor and other targets, offering a template for streamlined antibody generation at large.

Protein design and variant prediction using autoregressive generative models

The ability to design functional sequences and predict effects of variation is central to protein engineering and biotherapeutics. State-of-art computational methods rely on models that leverage evolutionary information but are inadequate for important applications where multiple sequence alignments are not robust. Such applications include the prediction of variant effects of indels, disordered proteins, and the design of proteins such as antibodies due to the highly variable complementarity determining regions. We introduce a deep generative model adapted from natural language processing for prediction and design of diverse functional sequences without the need for alignments. The model performs state-of-art prediction of missense and indel effects and we successfully design and test a diverse 105-nanobody library that shows better expression than a 1000-fold larger synthetic library. Our results demonstrate the power of the alignment-free autoregressive model in generalizing to regions of sequence space traditionally considered beyond the reach of prediction and design.

Rapid generation of potent antibodies by autonomous hypermutation in yeast

The predominant approach for antibody generation remains animal immunization, which can yield exceptionally selective and potent antibody clones owing to the powerful evolutionary process of somatic hypermutation. However, animal immunization is inherently slow, has poor compatibility with certain antigens ( e . g ., integral membrane proteins), and suffers from self-tolerance and immunodominance, which limit the functional spectrum of antibodies that can be obtained. Here, we describe A utonomous H ypermutation y E ast surf A ce D isplay (AHEAD), a synthetic recombinant antibody generation technology that imitates somatic hypermutation inside engineered yeast. In AHEAD, antibody fragments are encoded on an error-prone orthogonal DNA replication system, resulting in Saccharomyces cerevisiae populations that continuously mutate surface-displayed antibody repertoires. Simple cycles of yeast culturing and enrichment for antigen binding drive the evolution of high-affinity antibody clones in a readily parallelizable process that takes as little as 2 weeks. We applied AHEAD to generate nanobodies against the SARS-CoV-2 S glycoprotein, a GPCR, and other targets. The SARS-CoV-2 nanobodies, concurrently evolved from an open-source naïve nanobody library in 8 independent experiments, reached subnanomolar affinities through the sequential fixation of multiple mutations over 3-8 AHEAD cycles that saw ∼580-fold and ∼925-fold improvements in binding affinities and pseudovirus neutralization potencies, respectively. These experiments highlight the defining speed, parallelizability, and effectiveness of AHEAD and provide a template for streamlined antibody generation at large with salient utility in rapid response to current and future viral outbreaks.

Procedural and obstetric outcomes after embryo reduction vs fetal reduction in multifetal pregnancy

OBJECTIVE

To compare the obstetric outcome and incidence of procedure-related adverse events after embryo reduction (ER) vs fetal reduction (FR), in multifetal pregnancies undergoing reduction to twins or singletons.

METHODS

We analyzed retrospectively data from multifetal pregnancies that underwent transvaginal ER (n = 181) at a mean gestational age of 7.6 weeks or transabdominal FR (n = 115) at a mean gestational age of 12.9 weeks between December 2006 and January 2017. FR was performed after a detailed fetal anomaly scan. The two groups were compared with respect to obstetric outcomes, such as incidence of miscarriage, early or late preterm delivery, maternal complications and fetal loss, and procedure-related adverse events, including incidence of subchorionic hematoma and procedure-related fetal loss.

RESULTS

Compared with pregnancies that underwent ER, the incidence of procedure-related fetal loss was lower in the FR group (7.2% vs 0.9%; P = 0.039; odds ratio (OR), 0.12; 95% CI, 0.02-0.89). Mean gestational age at delivery for twins was 34.2 weeks in the ER group and 35.7 weeks in the FR group (P = 0.014). Compared with the ER group, the FR group had lower miscarriage (8.8% vs 2.6%; P = 0.045; OR, 0.28; 95% CI, 0.08-0.97) and overall fetal loss (13.3% vs 5.2%; P = 0.031; OR, 0.36; 95% CI, 0.14-0.91) rates.

CONCLUSIONS

The FR procedure is, overall, a better and safer approach to reducing morbidity and mortality in multifetal pregnancies. Spontaneous demise of one fetus may occur after ER, and FR has the advantage that chorionic villus sampling and ultrasound screening for increased nuchal translucency and anatomical defects can be conducted before the procedure. The ER approach is still reasonable when a patient's religious or other ethical concerns are of primary importance. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Individual Factors Affecting Self-esteem, and Relationships Among Self-esteem, Body Mass Index, and Body Image in Patients With Schizophrenia

The purposes of this study were to identify correlations between body mass index, body image, and self-esteem in patients with schizophrenia and to analyse the specific factors affecting self-esteem. This study had a descriptive design, utilising a cross-sectional survey. Participants were patients with schizophrenia who were admitted to a mental health facility in South Korea. A total of 180 questionnaires were distributed, and an appropriate total sample size of 167 valid questionnaires was analysed. Self-esteem was significantly correlated with body image, the subscale of appearance orientation, and body areas satisfaction. However, body mass index exhibited no significant correlation with any variable. The variables found to have a significant explanatory power of 21.4% were appearance orientation and body areas satisfaction. The explanatory power of all factors was 33.6%. The self-esteem of patients with schizophrenia was influenced by body mass index and body image. The positive symptoms of schizophrenia can be controlled by medication, whereas negative symptoms can be improved through education and nursing care with medication. Thus, psychiatric nurses should develop education and care programs that contribute to the positive body image and self-esteem of patients with schizophrenia.

The left middle temporal gyrus in the middle of an impaired social-affective communication network in social anxiety disorder

BACKGROUND

Previous studies on patients diagnosed with social anxiety disorder (SAD) reported changed patterns of the resting-state functional connectivity network (rs-FCN) between the prefrontal cortices and other prefrontal, amygdalar or striatal regions. Using a graph theory approach, this study explored the modularity-based community profile and patterns of inter-/intra-modular communication for the rs-FCN in SAD.

METHODS

In total, for 28 SAD patients and 27 healthy controls (HC), functional magnetic resonance imaging (fMRI) data were acquired in resting-state and subjected to a graph theory analysis.

RESULTS

The within-module degree z-score for a hub region [out of a total of 10 hub regions ranked using the participation coefficient] named left middle temporal gyrus was impaired in SAD compared to HC, proportional to the severity of clinician-scored and patient-reported functional impairment in SAD.

LIMITATIONS

Most of participants included in this study were undergraduate students in their early-to-mid 20's.

CONCLUSIONS

This study showed the importance of functional communication from the left middle temporal gyrus with other opercular-insular-subcortical regions for better objective functioning and lesser subjective disability in SAD.

Horizontal transfer of DNA methylation patterns into bacterial chromosomes

Horizontal gene transfer (HGT) is the non-inherited acquisition of novel DNA sequences. HGT is common and important in bacteria because it enables the rapid generation of new phenotypes such as antibiotic resistance. Here we show that in vivo and in vitro DNA methylation patterns can be horizontally transferred into bacterial chromosomes to program cell phenotypes. The experiments were performed using a synthetic system in Escherichia coli where different DNA methylation patterns within the cis-regulatory sequence of the agn43 gene turn on or off a fluorescent reporter (CFP). With this system we demonstrated that DNA methylation patterns not only accompany the horizontal transfer of genes into the bacterial cytoplasm but can be transferred into chromosomes by: (i) bacteriophage P1 transduction; and (ii) transformation of extracellular synthetic DNA. We also modified the experimental system by replacing CFP with the SgrS small RNA, which regulates glucose and methyl α-D-glucoside uptake, and showed that horizontally acquired DNA methylation patterns can increase or decrease cell fitness. That is, horizontally acquired DNA methylation patterns can result in the selection for and against cells that have HGT. Findings from these proof-of-concept experiments have applications in synthetic biology and potentially broad implications for bacterial adaptation and evolution.

Relative bioavailability of copper in tribasic copper chloride to copper in copper sulfate for laying hens based on egg yolk and feather copper concentrations

This experiment was conducted to determine the relative bioavailability (RBV) of Cu in tribasic copper chloride (TBCC) to Cu in copper sulfate (monohydrate form; CuSO4·H2O) for layer diets based on egg yolk and feather Cu concentrations. A total of 252, 72-wk-old Hy-Line Brown laying hens were allotted to 1 of 7 treatments with 6 replicates consisting of 6 hens per replicate in a completely randomized design. Hens were fed corn-soybean meal-based basal diets supplemented with 0 (basal), 100, 200, or 300 mg/kg Cu from CuSO4 or TBCC for 4 wk. Results indicated that egg production, egg weight, and egg mass were not affected by dietary treatments. However, increasing inclusion levels of Cu in diets from CuSO4 decreased (P < 0.05) feed conversion ratio (FCR), whereas increasing inclusion levels of Cu in diets from TBCC did not affect FCR, indicating significant interaction (P < 0.05). Increasing inclusion levels of Cu from TBCC or CuSO4 increased (P < 0.05) Cu concentrations of egg yolk and feathers. Feather Cu concentrations were greater (P < 0.01) for hens fed diets containing CuSO4 than for hens fed diets containing TBCC. The values for the RBV of Cu in TBCC to Cu in CuSO4 based on log10 transformed egg yolk and feather Cu concentrations were 107.4% and 69.5%, respectively. These values for the RBV of Cu in TBCC did not differ from Cu in CuSO4 (100%). The RBV measured in egg yolk did not differ from the RBV measured in feather. In conclusion, the RBV of Cu in TBCC to Cu in CuSO4 can be determined using Cu concentrations of egg yolk and feathers although the values depend largely on target tissues of laying hens. For a practical application, however, the RBV value of Cu in TBCC to Cu in CuSO4 could be 88.5% when the RBV values determined using egg yolk and feather Cu concentrations were averaged.

Paradoxical suppression of small RNA activity at high Hfq concentrations due to random-order binding

Small RNAs (sRNAs) are important regulators of gene expression during bacterial stress and pathogenesis. sRNAs act by forming duplexes with mRNAs to alter their translation and degradation. In some bacteria, duplex formation is mediated by the Hfq protein, which can bind the sRNA and mRNA in each pair in a random order. Here we investigate the consequences of this random-order binding and experimentally demonstrate that it can counterintuitively cause high Hfq concentrations to suppress rather than promote sRNA activity in Escherichia coli. As a result, maximum sRNA activity occurs when the Hfq concentration is neither too low nor too high relative to the sRNA and mRNA concentrations (‘Hfq set-point’). We further show with models and experiments that random-order binding combined with the formation of a dead-end mRNA–Hfq complex causes high concentrations of an mRNA to inhibit its own duplex formation by sequestering Hfq. In such cases, maximum sRNA activity requires an optimal mRNA concentration (‘mRNA set-point’) as well as an optimal Hfq concentration. The Hfq and mRNA set-points generate novel regulatory properties that can be harnessed by native and synthetic gene circuits to provide greater control over sRNA activity, generate non-monotonic responses and enhance the robustness of expression.

Vertical components of head-shaking nystagmus in vestibular neuritis, Meniere's disease and migrainous vertigo

OBJECTIVES

To describe vertical and horizontal components of head-shaking nystagmus (HSN) in various vestibular disorders.

DESIGN

Retrospective case review.

SETTING

Tertiary care academic referral centre.

PARTICIPANTS

Head-shaking nystagmus was assessed in 66 vestibular neuritis (VN) patients at acute (<7 days) and follow-up (2 months), and 65 Meniere's disease (MD) and 76 migrainous vertigo (MV) in interictal period.

MAIN OUTCOME MEASURES

Head-shaking nystagmus was categorised as pure horizontal, pure vertical or mixed. Horizontal HSN was classified as monophasic or biphasic and paretic or recovery. Vertical HSN was classified as upbeat or downbeat.

RESULTS

Abnormal HSN (pathologic monophasic, biphasic or delayed-peak HSN) showed different positive rates depending on the vestibular disorders and compensation (94% in acute VN; 89% in FU VN; 78% in MD; 50% in MV). Paretic HSN with the nystagmus towards the lesioned side was the most common type in VN and MD; however, recovery HSN with the nystagmus towards the intact side could be rarely observed especially in patients with MD or compensated VN. Vertical nystagmus could be combined with horizontal HSN, and upbeat HSN was observed in most (83%) of the patients with acute VN, but downbeat HSN was common in follow-up VN (83%), MD (97%) and MV (85%). Weak perverted HSN, which is assumed to be a central nystagmus, was rarely observed in MD and MV (6-9%), but not in VN.

CONCLUSIONS

Head-shaking nystagmus (HSN) in horizontal plane is a valuable tool in the assessment of vestibular imbalance. Common observation of upbeat HSN in acute VN and downbeat HSN in follow-up VN, MD and MV suggests that vertical components are possibly related to the involvement of vestibular apparatus and compensation. Weak perverted HSN and delayed-peak HSN were rarely observed in MD and MV, and never observed in VN, suggesting that it is possibly related to either asymmetrically impaired vertical canals or misorientation of the velocity-storage system.

Clinical outcomes and risk factors of post-polypectomy coagulation syndrome: a multicenter, retrospective, case-control study

BACKGROUND AND STUDY AIMS

Post-polypectomy coagulation syndrome (PPCS) is a well known complication of colonoscopic polypectomy. However, no previous studies have reported on the clinical outcomes or risk factors of PPCS. The aim of the current study was to analyze the clinical outcomes and risk factors of PPCS developing after a colonoscopic polypectomy.

PATIENTS AND METHODS

Data for all patients who underwent colonoscopic polypectomies and required hospitalization in nine university hospitals were analyzed retrospectively. The incidence, clinicopathological characteristics, and clinical outcomes of PPCS cases were examined. Additionally, patients who developed PPCS were compared with controls who were matched by age and sex, in order to assess for possible risk factors.

RESULTS

The rate of PPCS that required hospitalization after colonoscopic polypectomy was 0.7/1000. All patients with PPCS were treated medically without the need for surgical interventions. The median durations of therapeutic fasting, hospitalization, and antibiotic use were 3 days, 5.5 days, and 7 days, respectively. The rates of major PPCS and mortality were 2.9 % and 0 %, respectively. On multivariate analysis, hypertension (OR = 3.023, 95 %CI 1.034 - 8.832), large lesion size (OR = 2.855, 95 %CI 1.027 - 7.937), and non-polypoid configuration (OR = 3.332, 95 %CI 1.029 - 10.791) were found to be independent risk factors related to the development of PPCS.

CONCLUSIONS

In this study, the rates of major PPCS and mortality were only 2.9 % and 0 %, respectively. Hypertension, large lesion size, and non-polypoid configuration of the lesion were independently associated with PPCS. Therefore, patients may be reassured by the excellent prognosis of PPCS, while endoscopists should be especially careful when performing colonoscopic polypectomies in patients with hypertension or large and non-polypoid lesions.

Involvement of retinoic acid-induced peroxiredoxin 6 expression in recovery of noise-induced temporary hearing threshold shifts

All-trans retinoic acid (ATRA) is reported to reduce hair cell loss and hearing deterioration caused by noise-induced hearing loss (NIHL). The present study investigates the involvement of peroxiredoxin 6 (Prdx 6) in ATRA-mediated protection of temporary threshold shift of hearing. Mice fed with ATRA before or after exposure to white noise showed a faster recovery than untreated controls within 1 week, with a concomitant increase of cochlear Prdx 6 expression. Treatment of mouse auditory cells with ATRA induced Prdx 6 expression. A putative retinoic acid (RA)-response element (RARE) was identified in a murine Prdx 6 promoter region. Prdx 6 promoter activities were elevated in wild-type reporter plasmid-transfected cells, whereas no significant change in activity was in those with RARE-disrupted mutant reporter. RA receptor α (RARα) functions as a transactivator of Prdx 6 gene expression. These findings suggest that ATRA-induced Prdx 6 expression may be associated with rapid recovery from temporary NIHL.

Criteria for decision making after endoscopic resection of well-differentiated rectal carcinoids with regard to potential lymphatic spread

BACKGROUND AND STUDY AIM

Rectal carcinoids are low-grade malignancies that are usually treated by endoscopic resection. However, on pathologic examination, resection margins that are positive for carcinoid cells are frequently found. Patient outcomes were reviewed after endoscopic resection of rectal carcinoids and the clinical significance of possible residual disease, as defined by pathologic and endoscopic examination, was evaluated.

PATIENTS AND METHODS

The medical records and endoscopic findings of 347 patients presenting with rectal carcinoids to 14 university hospitals in Korea between January 1999 and June 2007 were retrospectively analyzed.

RESULTS

A total of 304 patients were treated with endoscopic resection, and 43 patents were treated with surgery. In the endoscopic resection group, the complete resection rate was 88.2% based on endoscopic appearance (CR-E) and 60.2% based on pathologic evaluation (CR-P). The agreement between CR-E and CR-P was low (κ=0.192). No residual tumors were found in 77 of 85 patients (90.6%) who were CR-E but not CR-P and who had endoscopic biopsy taken at 24-month follow-up. The receiver-operating characteristic curve identified an optimal cut-off value of 10.5 mm, at which the sensitivity and the specificity for metastasis were 100% and 89%, respectively. The risk factors for metastasis by multivariate analysis were tumor size, increased mitotic rate, and lymphovascular invasion.

CONCLUSIONS

Endoscopic resection is a safe and effective modality for treating well-differentiated rectal carcinoids smaller than 10 mm in diameter. Discrepancies were observed between CR-E and CR-P. The risk factors for metastasis were tumor size, increased mitotic rate, and lymphovascular invasion.

Up-regulation of hypoxia-inducible factor-1 alpha by cobalt chloride prevents hearing loss in noise-exposed mice

Since hypoxia-inducible factor-1α (HIF-1α) is the key transcription factor that enables cells to survive in hypoxia, we have investigated whether an upregulation of HIF-1α prevents the noise-induced hearing loss in BALB/c hybrid mice, which were intraperitoneally injected with CoCl(2) (a HIF-1α inducer) and exposed to white band noise with 120 dB peak equivalent sound pressure level for 3h once daily for 3 days. In the CoCl(2) treatment group, HIF-1α was found to be up-regulated in the cochlear tissues and the hearing loss was largely prevented. Histologically, the loss of sensory hair cells was also significantly lower in the CoCl(2) treatment group than the Control group. However, YC-1 (a HIF-1α inhibitor) attenuated the preventive effect of CoCl(2) on the noise-induced hearing loss. These results suggest that HIF-1α plays a crucial role in the prevention against noise trauma in the inner ear.

Test-retest reliability of vibration-induced nystagmus in peripheral dizzy patients

The purpose of this study was to analyze test-retest reliability of vibration-induced nystagmus (VIN) in dizzy patients. Fifty-two consecutive patients with positive eye movements induced by vibration at all four different stimulation sites were enrolled. Evaluation of VIN was repeated in 2 separate sessions, 30 minutes apart. Maximum slow-phase eye velocities at different sites from the first and second sessions were assessed via the intraclass correlation coefficient (ICC) and the Pearson correlation coefficient. The incidence of directional changing of evoked nystagmus and the abnormal rates were also evaluated. Excellent reliability with ICC values ranging from 0.89–0.98 and substantial-to-excellent correlation was obtained for the maximum slow-phase eye velocities at different sites. The incidence of directional changes of evoked nystagmus was 0%–4% at each stimulation site. Forty-three patients (83%) had abnormal results in the first session and 41 patients (79%) had abnormal results in the second session. Overall, the direction and maximum slow-phase eye velocities of VIN for different stimulation sites had excellent test-retest reliability. The VIN test is a reliable test for detecting vestibular imbalance in evaluating a dizzy patient.

Outcome evaluation of carotid stenting in high-risk patients with symptomatic carotid near occlusion

Management of symptomatic carotid near occlusion especially in high-risk patients is different from outcome analysis of NASCET. We evaluated outcome in high-risk patients with symptomatic near occlusion. For 48 patients with near occlusion out of 166 symptomatic high-risk patients who underwent carotid stenting, we assessed the procedural success defined as residual stenosis <30%, modified Rankin Scale (mRS) at one and six months following stenting, and the 13 cerebrovascular factors related to the outcome. Initial National Institutes of Health Stroke Scale (NIHSS) ≥4, 1-3 and 0 were 13, 14 and 21 patients each. We compared the outcome with patients who underwent CAS (n=118) due to symptomatic stenosis without near occlusion during the same period. Our procedural success rate was 98%. A good outcome (mRS ≤2) was achieved in 44 patients (92%) at six months. There were five events (10%) within six months, i.e. three minor strokes, one major stroke caused by hemorrhage, and one death excluding two deaths not related to stroke. Hyperperfusion (n=4) was the most common cause of events leading to two minor strokes and a major stroke. Although initial NIHSS (P = .012) was related to poor outcome (mRS >2) compared to the CAS group, there was no statistical significance between two groups in the event rate of stroke, death or restenosis. The outcome of carotid stenting in high-risk patients with symptomatic near occlusion did not reveal any difference compared with CAS. Poor outcome was related to the initial NIHSS (≥4). Hyperperfusion tended to be more commonly related to an event occurring after stenting.

Adaptor protein sorting nexin 17 regulates amyloid precursor protein trafficking and processing in the early endosomes

Accumulation of extracellular amyloid beta peptide (Abeta), generated from amyloid precursor protein (APP) processing by beta- and gamma-secretases, is toxic to neurons and is central to the pathogenesis of Alzheimer disease. Production of Abeta from APP is greatly affected by the subcellular localization and trafficking of APP. Here we have identified a novel intracellular adaptor protein, sorting nexin 17 (SNX17), that binds specifically to the APP cytoplasmic domain via the YXNPXY motif that has been shown previously to bind several cell surface adaptors, including Fe65 and X11. Overexpression of a dominant-negative mutant of SNX17 and RNA interference knockdown of endogenous SNX17 expression both reduced steady-state levels of APP with a concomitant increase in Abeta production. RNA interference knockdown of SNX17 also decreased APP half-life, which led to the decreased steady-state levels of APP. Immunofluorescence staining confirmed a colocalization of SNX17 and APP in the early endosomes. We also showed that a cell surface adaptor protein, Dab2, binds to the same YXNPXY motif and regulates APP endocytosis at the cell surface. Our results thus provide strong evidence that both cell surface and intracellular adaptor proteins regulate APP endocytic trafficking and processing to Abeta. The identification of SNX17 as a novel APP intracellular adaptor protein highly expressed in neurons should facilitate the understanding of the relationship between APP intracellular trafficking and processing to Abeta.

Mechanisms of Vibration-Induced Nystagmus in Normal Subjects and Patients with Vestibular Neuritis

It has been reported that vibration applied either on the mastoid or on the sternocleidomastoid (SCM) muscles induces nystagmus in normal subjects or patients after unilateral vestibular neuritis (VN). The aims of the study were to characterize vibration-induced nystagmus (VIN) in normal and patient groups and to propose the mechanism of VIN. We recorded eye movements during unilateral 100-Hz vibration on the mastoid bone and SCM muscles in 22 normal subjects and 19 patients with unilateral VN. In normal subjects, the direction of slow-phase velocity (SPV) tended to be toward the vibrated side. Vibration on the right/left SCM muscles induced mean SPV of 1.7 degrees/s, -1.9 degrees/s toward the stimulated side in all normal subjects. Vibration on the right/left mastoid bone induced mean SPV of 1.5 degrees/s, -0.4 degrees/s toward the stimulated side in most of the normal subjects. Positive value means SPV to the right side. This directional preponderance to the vibrated side was statistically significant. Among the patients with VN, the slow phase of the VIN was directed towards the lesioned side, irrespective of whether vibration was applied on the lesioned or intact side. Vibration on the right/left mastoid bone induced mean SPV of -10.4 degrees/s, -10.8 degrees/s toward the lesioned side. Vibration on the right/left SCM induced mean SPV of -7.9 degrees/s, -10.5 degrees/s toward the lesioned side. The amplitude of SPV showed a significant correlation with the unilateral weakness of caloric test. Our results suggest that the proprioceptive stimulation plays a major role in producing VIN in normal subjects, while VIN is generated mostly by the vestibular stimulation in patients with unilateral VN, which helps us localize the lesion side. Vibration tests on the SCM muscles as well as on the mastoid are recommended and our hypothetic mechanisms of VIN are presented.

Inner Ear Anomalies in Cochlear Implantees

OBJECTIVE

To classify the inner ear anomalies of cochlear implantees with profound sensorineural hearing loss.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

For the normative data of the inner ear structures, the temporal bone computed tomography of 60 patients (120 ears) with normal bone-conduction threshold (< 15 dB) were used, and the data were applied to 570 ears of 285 cochlear implantees.

INTERVENTIONS

Predesignated inner ear structures were measured in temporal bone computed tomography images from the normal and cochlear implantation groups using a computer-based caliper that formed part of a picture archiving and communication system.

MAIN OUTCOME MEASURES

The inner ear anomalies were defined when the structures presented visually obvious malformations or the measurements deviated 2 standard deviations from the means in the normative data.

RESULTS

The application of normative data to 570 profound SNHL ears resulted in the identification of 293 individual anomalies in 127 anomalous ears. An enlarged vestibular aqueduct was the most common individual anomaly (49 cases), followed by vestibular enlargement (38 cases) and other semicircular canal dysplasia (37 cases). When the individual anomalies were reaccounted according to the more prominent anomaly where multiple anomalies were present in each ear, incomplete partition type II was the most common (34 ears), followed by cochlear hypoplasia (22 ears) and incomplete partition type I (20 ears).

CONCLUSION

We suggested a measurement technique for the inner ear structures using computed tomography and derived normative measurements helpful for diagnosing inner ear anomalies. Using these normative data, we classified the inner ear anomalies of profound SNHL ears in cochlear implantees.

Analysis of voice and quantitative measurement of glottal gap after thyroplasty type I in the treatment of unilateral vocal paralysis

Thyroplasty type I is one of several surgical treatments in which improving the voice of unilateral vocal fold paralysis is the ultimate objective. The goal of the surgery is the medialization of the paralyzed vocal fold. The purpose of this study is to evaluate the effectiveness of thyroplasty type I through acoustical analysis, aerodynamic measures, and quantitative videostroboscopic measurements. We report on 20 patients with unilateral vocal cord paralysis who underwent thyroplasty type I. We performed preoperative and postoperative video image analysis (normalized glottal gap area) and computer-assisted voice analysis (fundamental frequency, jitter, shimmer, noise-to-harmonic ratio, mean phonation time, mean flow rate, mean subglottic pressure) in all patients. The glottal gap was significantly reduced after thyroplasty type I. Postoperative voice quality was characterized by an improved pitch and amplitude pertubation (jitter and shimmer), phonation time (mean phonation time), and subglottic pressure (mean subglottic pressure). Thyroplasty type I is an effective method for regaining glottal closure and vocal function.

Changing trends in clinical manifestations of laryngeal tuberculosis

OBJECTIVES/HYPOTHESIS

Despite the dramatic decrease in the incidence of laryngeal tuberculosis, the disease has gained new interest as a result of claims that it has changed its clinical patterns. The aim of this study is to evaluate the changing trends in clinical manifestations of laryngeal tuberculosis.

STUDY DESIGN

Retrospective clinical analysis.

METHODS

Clinical analysis of 22 patients with pathologically confirmed laryngeal tuberculosis was carried out retrospectively.

RESULTS

Patients' ages ranged from 22 to 75 years. The male-to-female ratio was 2.14 to 1. The most frequent chief complaint was hoarseness. The true vocal cord and the false vocal cord were commonly involved, and 11 patients showed single lesions. Among 22 patients, only 7 had active pulmonary tuberculosis, and 9 were proven to have normal lung status. The patients with active pulmonary tuberculosis showed more ulcerative and multiple lesions. The patients with normal lung status showed nonspecific, polypoid, and single lesions. All patients responded satisfactorily to antituberculous medication.

CONCLUSIONS

The clinical manifestations of laryngeal tuberculosis have changed and seem to be different from those of classic reports. It can even occur without pulmonary tuberculosis, and the characteristics of lesions seem to be more nonspecific. It might be important to consider tuberculosis in the differential diagnosis of nonspecific laryngeal disease.

Salivary gland choristoma of the middle ear: a case report

A choristoma is a nonneoplastic proliferation of histologically normal tissue that forms at an abnormal site. It is extremely uncommon in the middle ear space. It appears to be a developmental abnormality and may be associated with abnormalities of adjacent structures. It usually occurs with unilateral conductive hearing loss and requires a differential diagnosis from other mass lesions in the middle ear cavity. This article discusses a case of salivary gland choristoma of the middle ear that we believe to be the 24th case reported on this subject.

Protective effects of asiaticoside derivatives against beta-amyloid neurotoxicity

Asiaticoside (AS) derivatives were tested for potential protective effects against Abeta-induced cell death. Of the 28 AS derivatives tested, asiatic acid (AA), asiaticoside 6 (AS6), and SM2 showed strong inhibition of Abeta-induced death of B103 cells at 1 microM. The three AS derivatives were further tested for their effects on free radical injury and apoptosis. All three AS derivatives reduced H(2)O(2)-induced cell death and lowered intracellular free radical concentration, but AA showed the strongest protection. In contrast, SM2 was the most effective blocker of staurosporine-induced apoptosis. These results suggest that the three AS derivatives block Abeta toxicity by acting through different cellular mechanisms. When applied to hippocampal slices, AA, SM2, and AS6 did not alter n-methyl-D-aspartic acid (NMDA) or non-NMDA receptor-mediated synaptic transmission, paired-pulse facilitation or induction of long-term potentiation in the field CA1. These results indicate that the three AS derivatives do not alter physiological properties of the hippocampus at the concentration that blocks Abeta-induced cell death. Therefore AS6, AA, and SM2 can be regarded as reasonable candidates for a therapeutic Alzheimer's disease drug that protects neurons from Abeta toxicity.

Presenilin 1 mediates protein kinase C dependent alpha-secretase derived amyloid precursor protein secretion and mitogen-activated protein kinase activation in presenilin 1 transfected human embryonic kidney 293 cell

We investigated the role of presenilin 1 (PS1) in the secretion of alpha-secretase derived amyloid precursor protein (sAPP alpha) and associated intracellular signaling pathways. Human embryonic kidney (HEK) 293 cells were transfected with exon 9 deletion (deltaE9) mutant PS1 cDNA in an ecdyson-inducible system. sAPPalpha secretion was lower in the mutant PS1 expressing cells compared with non-expressing cells. When activated by PDBu, secretion of sAPPalpha and the level of phosphorylated mitogen activated protein kinase (MAPK) were greatly enhanced in deltaE9 PS1 uninduced cells, but not in the mutant PS1 induced cells. PD98059, a MAPK inhibitor, blocked PDBu induced sAPPalpha secretion from deltaE9 PS1 uninduced cells but had no effect on the mutant PS1 induced cells. These data indicate that PS1 mediates PDBu-induced sAPPalpha secretion and MAPK activation.

Lipo-oligosaccharides of Campylobacter jejuni serotype O:10. Structures of core oligosaccharide regions from a bacterial isolate from a patient with the Miller-Fisher syndrome and from the serotype reference strain

Lipo-oligosaccharide (LOSa) was obtained by phenol-water extraction of bacterial cells of an isolate PG 836, identified as Campylobacter jejuni serotype O:10, from a patient who subsequently developed the Miller-Fisher syndrome (MFS). The product was separated into a water-insoluble gel of low Mr and a water-soluble component of high Mr. The structure of the core oligosaccharide region in LOSa is reported herein for comparison with LOSb from the C. jejuni O:10 reference strain, and is based on investigations carried out on: (1) O-deacylated LOSa; (2) the core oligosaccharide (OS 1a) liberated on acetic acid hydrolysis of the ketosidic linkages to lipid A, with accompanying loss of N-acetylneuraminic acid residues; (3) the product of the removal of phosphate residues from OS 1a to give OS 2a; and (4) the Smith degradation of OS 2a to yield a mixture of Os 3a and OS 4a. The results revealed that the core oligosaccharide region in LOSa from the MFS bacterial isolate had chains (1a), of which some were terminated by an N-acetylneuraminobiose [Neu5Ac(alpha 2-8)Neu5Ac] unit in a GD3 [Neu5Ac-Neu5Ac-Gal] epitope, and the inner regions of which were different from those of other C. jejuni serotypes. Similar experiments on LOSb from bacterial cells of the C. jejuni O:10 reference strain showed that the core oligosaccharide unit [1a, R = P (phosphoric monoester)] of LOSa from the MFS isolate was more uniformly complete than that of the O:10 reference strain [1b, R = AEP (2-aminoethylphosphate)] differing in the nature of the phosphate substituent at the inner heptose residue. The close structural relationship of LOSa from the MFS associated bacterium to LOSb from the O:10 reference strain runs parallel to that of the previously studied Guillain-Barré syndrome (GBS) associated bacterium typed as C. jejuni O:19 in comparison with the lipo-oligosaccharide from the reference strain. Preliminary studies on the high Mr components showed that those from the O:10 strains were indistinguishable from each other, but were structurally unrelated to those from the GBS associated C. jejuni serotype O:19 isolates and the O:19 reference strain [G.O. Aspinall, A.G. McDonald, and H. Pang, Biochemistry, 33 (1994) 250-255].

Structure of the specific oligosaccharides from the glycopeptidolipid antigens of serovars in the Mycobacterium avium-Mycobacterium intracellulare-Mycobacterium scrofulaceum complex

The specific oligosaccharide units of the C-mycosidic glycopeptidolipid antigens from serovarieties in the Myobacterium avium-Mycobacterium intracellulare-Mycobacterium scrofulaceum complex were liberated as oligosaccharide alditols by treatment of the glycopeptidolipids with alkaline borohydride. The complete structures of the oligosaccharide alditols have been derived from their 1H-NMR spectra or those of their permethylated (or pertrideuteriomethylated) derivatives, the mass spectra of the methylated derivatives, and from methylation fragmentation analysis. Periodate oxidation was also used to confirm the position of the link between the ultimate and penultimate sugars. The following structures are proposed (with some extrapolation of enantiomeric configurations where evidence for assignment is not yet complete) for the oligosaccharide alditols: Serovar 9 2,3-Me2-alpha-L-Fucp-(1 leads to 4)-2,3-Me2-alpha-L-Fucp-(1 leads to 3)-alpha-L-Rhap-(1 leads to 2)-6-deoxy-L-Talol Serovar 25 2-Me-alpha-L-Fucp-(1 leads to 4)-2-Me-alpha-L-Fucp-(1 leads to 3)-alpha-L-Rhap-(1 leads to 2)-6-deoxy-L-talol Serovar 8 4,6-(1'-carboxyethylidene)-3-Me-beta-D-Glcp-(1 leads to 3)-alpha-L-Rhap-(1 leads to 2)-6-deoxy-L-Talol Thus, 6-deoxytalitol (6-deoxytalose in the original glycopeptidolipid) invariably occupies the reducing terminus. Rhamnose is invariably the penultimate sugar, and the link between rhamnose and 6-deoxytalose is invariably alpha 1 leads to 2. Moreover, the results point to the outer one or two appendages for the provision of individually distinctive features required for antigen specificity. The abbreviations used are: serovar, serologically distinct varieties; Me, methyl; Fucp, fucopyranose; Rhap, rhamnopyranose; Talol, talitol.