Significance of photodocumentation-associated factors in colonoscopy on the detection rate of colorectal neoplasms

OBJECTIVE

It is unclear whether photodocumentation is associated with colorectal neoplasm (CRN) detection at colonoscopy, despite its ability to take more images with the development of affordable digital imaging systems. This study aimed to investigate whether photodocumentation-related factors could affect the detection rate of CRNs in healthy subjects.

PATIENTS AND METHODS

A total of 2,637 subjects undergoing screening colonoscopy in routine health check-ups at CHA Bundang Medical from January to September 2016 were enrolled in this study. Only the endoscopic image data for observation purposes during colonoscopy withdrawal was used in this analysis. The number of observation images, observation time and the speed of photodocumentation (SPD) defined as the number of observation images per minute were used as quantity measures of photodocumentation. The presence of documented anatomical landmarks such as appendix orifice (AO), ileocecal valve (ICV), anorectal junction was used as quality measures of photodocumentation.

RESULTS

Among subject-related factors, the independent factors for CRN detection in the multivariate analysis were age, male sex, waist circumference, and family history of colorectal cancer. In photo-documentation-related factors, SPD [Odds ratio (OR) 0.800; 95% confidence interval (CI), 0.740 to 0.864], observation time over 6 min (OR 1.671; 95% CI, 1.145 to 2.439), clear documentation of appendix orifice (AO) (OR 5.976; 95% CI, 4.548 to 7.852) and ileocecal valve (ICV) (OR 3.826; 95% CI, 2.985 to 4.904), and endoscopists (p < 0.001) were independently significant factors. However, the number of observation images was not associated with the detection of CRNs.

CONCLUSIONS

Lower SPD and clear documentation of cecal landmarks might be associated with an increased detection rate of CRNs.

Atomic-scale interpretation of the quantum oscillations in cuprate superconductors

Cuprate superconductors display unusual features in bothkspace and real space as the superconductivity is suppressed-a broken Fermi surface, charge density wave, and pseudogap. Contrarily, recent transport measurements on cuprates under high magnetic fields report quantum oscillations (QOs), which imply rather a usual Fermi liquid behavior. To settle the disagreement, we investigated Bi₂Sr₂CaCu₂O_8+δunder a magnetic field in an atomic scale. A particle-hole (p-h) asymmetrically dispersing density of states (DOSs) modulation was found at the vortices on a slightly underdoped sample, while on a highly underdoped sample, no trace of the vortex was found even at 13 T. However, a similar p-h asymmetric DOS modulation persisted in almost an entire field of view. From this observation, we infer an alternative explanation of the QO results by providing a unifying picture where the aforementioned seemingly conflicting evidence from angle-resolved photoemission spectroscopy, spectroscopic imaging scanning tunneling microscopy, and magneto-transport measurements can be understood solely in terms of the DOS modulations.

Probing Gluon Spin-Momentum Correlations in Transversely Polarized Protons through Midrapidity Isolated Direct Photons in p^{↑}+p Collisions at sqrt[s]=200 GeV

Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in p^{↑}+p collisions at sqrt[s]=200  GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). Because direct photons in particular are produced from the hard scattering and do not interact via the strong force, this measurement is a clean probe of initial-state spin-momentum correlations inside the proton and is in particular sensitive to gluon interference effects within the proton. This is the first time direct photons have been used as a probe of spin-momentum correlations at RHIC. The uncertainties on the results are a 50-fold improvement with respect to those of the one prior measurement for the same observable, from the Fermilab E704 experiment. These results constrain gluon spin-momentum correlations in transversely polarized protons.

The Association of Gait Speed and Frontal Lobe among Various Cognitive Domains: The Korean Frailty and Aging Cohort Study (KFACS)

OBJECTIVE

The aim of this study was to determine how gait speed and frontal lobe functionsin community-dwelling older adults in Korea.

DESIGN

This was a cross-sectional study.

SETTING

The study used data from the Korean Frailty and Aging Cohort Survey (KFACS), a multi-center longitudinal study addressing 10 centers across urban, rural, and suburban communities in Korea, between 2016 and 2017.

PARTICIPANTS

A total of 1552 older adults who underwent both gait speed tests and cognitive functions tests during the investigation of the KFACS.

MEASUREMENTS

Gait speed was assessed by asking participants to walk from a starting point to a point 4 meters away at a normal gait. Cognitive functions were evaluated using various standardized cognitive functions tests.

RESULTS

Gait speed was slower when participants were older or less educated The percentage of women, higher BMI, people with lower incomes, singles, smokers, and drinkers was high in the slower gait group. Also, all cognitive function scores were low and depression score was high in the group with slower walking speed. The slower walking speed showed low physical activity score and high prevalence of hypertension, osteoarthritis and osteoporosis. Among the seven cognitive functions (MMSE, memory, TMT, Recall, Recognition, digit span, and Fab), only TMT showed no significant difference between different gait speed groups. The other six cognitive functions showed higher results in the fastest gait speed group (T3), Participants in middle gait speed group (T2) also showed higher results in five of the seven cognitive function scores as well (Memory, Recall, Recognition, digit span, and Fab).

CONCLUSION

In this study, we found correlation between the slower gait speeds and the decrease in cognitive function, and especially the frontal lobe dysfunction was most prominent of all cognitive dysfunctions.

Nuclear Dependence of the Transverse Single-Spin Asymmetry in the Production of Charged Hadrons at Forward Rapidity in Polarized p+p, p+Al, and p+Au Collisions at sqrt[s_{NN}]=200 GeV

We report on the nuclear dependence of transverse single-spin asymmetries (TSSAs) in the production of positively charged hadrons in polarized p^{↑}+p, p^{↑}+Al, and p^{↑}+Au collisions at sqrt[s_{NN}]=200  GeV. The measurements have been performed at forward rapidity (1.4<η<2.4) over the range of transverse momentum (1.8<p_{T}<7.0  GeV/c) and Feynman x (0.1<x_{F}<0.2). We observed positive asymmetries for positively charged hadrons in p^{↑}+p collisions, and significantly reduced asymmetries in p^{↑}+A collisions. These results reveal a nuclear dependence of TSSAs for charged-hadron production in a regime where perturbative techniques are applicable. These results provide new opportunities to use p^{↑}+A collisions as a tool to investigate the rich phenomena behind TSSAs in hadronic collisions and to use TSSAs as a new handle in studying small-system collisions.

Beam Energy and Centrality Dependence of Direct-Photon Emission from Ultrarelativistic Heavy-Ion Collisions

The PHENIX collaboration presents first measurements of low-momentum (0.4<p_{T}<3  GeV/c) direct-photon yields from Au+Au collisions at sqrt[s_{NN}]=39 and 62.4 GeV. For both beam energies the direct-photon yields are substantially enhanced with respect to expectations from prompt processes, similar to the yields observed in Au+Au collisions at sqrt[s_{NN}]=200. Analyzing the photon yield as a function of the experimental observable dN_{ch}/dη reveals that the low-momentum (>1  GeV/c) direct-photon yield dN_{γ}^{dir}/dη is a smooth function of dN_{ch}/dη and can be well described as proportional to (dN_{ch}/dη)^{α} with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high p_{T} (>5  GeV/c), but when results from different collision energies are compared, an additional sqrt[s_{NN}]-dependent multiplicative factor is needed to describe the integrated-direct-photon yield.

Cooper Pair Density of Bi2Sr2CaCu2O8+ x in Atomic scale at 4.2 K

In pursuit of the elusive mechanism of high- T _C superconductors (HTSC), spectroscopic imaging scanning tunneling microscopy (SI-STM) is an indispensable tool for surveying local properties of HTSC. Since a conventional STM utilizes metal tips, which allow the examination of only quasiparticles and not superconducting (SC) pairs, Josephson tunneling using STM has been demonstrated by many authors in the past. An atomically resolved scanning Josephson tunneling microscopy (SJTM), however, was realized only recently on Bi₂Sr₂CaCu₂O_{8+ x} (Bi-2212) below 50 mK and on the Pb(110) surface at 20 mK. Here we report the atomically resolved SJTM on Bi₂Sr₂CaCu₂O_{8+ x} at 4.2 K using Bi-2212 tips created in situ. The I- V characteristics show clear zero bias conductance peaks following Ambegaokar-Baratoff (AB) theory. A gap map was produced for the first time using an atomically resolved Josephson critical current map I _C( r) and AB theory. Surprisingly, we found that this new gap map is anticorrelated to the gap map produced by a conventional method relying on the coherence peaks. Quasiparticle resonance due to a single isolated zinc atom impurity was also observed by SJTM, indicating that atomically resolved SJTM was achieved at 4.2 K. Our result provides a starting point for realizing SJTM at even higher temperatures, rendering possible investigation of the existence of SC pairs in HTSC above the T _C.

Pseudorapidity Dependence of Particle Production and Elliptic Flow in Asymmetric Nuclear Collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200 GeV

Asymmetric nuclear collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200  GeV provide an excellent laboratory for understanding particle production, as well as exploring interactions among these particles after their initial creation in the collision. We present measurements of charged hadron production dN_{ch}/dη in all such collision systems over a broad pseudorapidity range and as a function of collision multiplicity. A simple wounded quark model is remarkably successful at describing the full data set. We also measure the elliptic flow v_{2} over a similarly broad pseudorapidity range. These measurements provide key constraints on models of particle emission and their translation into flow.

Measurements of Multiparticle Correlations in d+Au Collisions at 200, 62.4, 39, and 19.6 GeV and p+Au Collisions at 200 GeV and Implications for Collective Behavior

Recently, multiparticle-correlation measurements of relativistic p/d/^{3}He+Au, p+Pb, and even p+p collisions show surprising collective signatures. Here, we present beam-energy-scan measurements of two-, four-, and six-particle angular correlations in d+Au collisions at sqrt[s_{NN}]=200, 62.4, 39, and 19.6 GeV. We also present measurements of two- and four-particle angular correlations in p+Au collisions at sqrt[s_{NN}]=200  GeV. We find the four-particle cumulant to be real valued for d+Au collisions at all four energies. We also find that the four-particle cumulant in p+Au has the opposite sign as that in d+Au. Further, we find that the six-particle cumulant agrees with the four-particle cumulant in d+Au collisions at 200 GeV, indicating that nonflow effects are subdominant. These observations provide strong evidence that the correlations originate from the initial geometric configuration, which is then translated into the momentum distribution for all particles, commonly referred to as collectivity.

Nuclear Dependence of the Transverse-Single-Spin Asymmetry for Forward Neutron Production in Polarized p+A Collisions at sqrt[s_{NN}]=200 GeV

During 2015, the Relativistic Heavy Ion Collider (RHIC) provided collisions of transversely polarized protons with Au and Al nuclei for the first time, enabling the exploration of transverse-single-spin asymmetries with heavy nuclei. Large single-spin asymmetries in very forward neutron production have been previously observed in transversely polarized p+p collisions at RHIC, and the existing theoretical framework that was successful in describing the single-spin asymmetry in p+p collisions predicts only a moderate atomic-mass-number (A) dependence. In contrast, the asymmetries observed at RHIC in p+A collisions showed a surprisingly strong A dependence in inclusive forward neutron production. The observed asymmetry in p+Al collisions is much smaller, while the asymmetry in p+Au collisions is a factor of 3 larger in absolute value and of opposite sign. The interplay of different neutron production mechanisms is discussed as a possible explanation of the observed A dependence.

Trends in device utilization ratios in intensive care units over 10-year period in South Korea: device utilization ratio as a new aspect of surveillance

BACKGROUND

Device-associated infection (DAI) is an important issue related to patient safety. It is important to reduce unnecessary device utilization in order to decrease DAI rates.

AIM

To investigate the time trend of device utilization ratios (DURs) of voluntarily participating hospitals, collected over a 10-year period through the Korean National Healthcare-associated Infections Surveillance System (KONIS).

METHODS

DURs from 2006 to 2015 in 190 intensive care units (ICUs) participating in KONIS were included in this study. DURs were calculated as the ratio of device-days to patient-days. The pooled incidences of DAIs and DURs were calculated for each year of participation, and the year-wise trends were analysed.

FINDINGS

Year-wise ventilator utilization ratio (V-DUR) increased significantly from 0.40 to 0.41 (F = 6.27, P < 0.01), urinary catheter utilization ratio (U-DUR) increased non-significantly from 0.83 to 0.84 (F = 1.66, P = 0.10), and C-line utilization ratio (CL-DUR) decreased non-significantly from 0.55 to 0.51 (F = 1.62, P = 0.11). In the subgroup analysis, 'medical ICU' (F = 2.79, P < 0.01) and 'hospital with >900 beds' (F = 3.07, P < 0.01) were associated with the significant increase in V-DUR.

CONCLUSION

In Korea, V-DUR showed a significant, year-wise increasing trend. The trends for U-DUR and CL-DUR showed no significant decrease. Efforts are required to ensure the reduction of DURs.

Development of a finger-like mechanism of end-effector for micro surgery

Neurosurgery had been considered nearly impossible due to its technical difficulty and the danger to its special target organ, but with endoscopic methods, many such surgeries can be made safely through the nose. Endoscopic neurosurgery is limited by available instruments, however, and there remain some areas of the human body inaccessible to standard surgical tools. To overcome some of these limitations, in this study we developed a simple mechanism that could form a high curvature in a narrow space. The end product is a finger-like mechanism consisting of five body parts and four joints. All body parts are connected in series, having a total length of 20mm and a diameter of φ4mm. A four-bar linkage internally connects the body parts and joints, and a nitinol backbone was used to improve repeatability. The first joint is driven by a rod or wire, and the shape of the mechanism is determined by rotating the first joint, because the position of each joint depends on the position of the joint before it. The study verified that an image sensor in the end of the finger-like mechanism has a wider range of view, 210 degrees than a conventional endoscope of 100 degrees. Finally, skull model simulation suggests that this device could be used in real neurosurgical applications.

Improved design for a low temperature scanning tunneling microscope with an in situ tip treatment stage

The Low Temperature Scanning Tunneling Microscope (LT-STM) is an extremely valuable tool not only in surface science but also in condensed matter physics. For years, numerous new ideas have been adopted to perfect LT-STM performances-Ultra-Low Vibration (ULV) laboratory and the rigid STM head design are among them. Here, we present three improvements for the design of the ULV laboratory and the LT-STM: tip treatment stage, sample cleaving stage, and vibration isolation system. The improved tip treatment stage enables us to perform field emission for the purpose of tip treatment in situ without exchanging samples, while our enhanced sample cleaving stage allows us to cleave samples at low temperature in a vacuum without optical access by a simple pressing motion. Our newly designed vibration isolation system provides efficient space usage while maintaining vibration isolation capability. These improvements enhance the quality of spectroscopic imaging experiments that can last for many days and provide increased data yield, which we expect can be indispensable elements in future LT-STM designs.

Centrality-Dependent Modification of Jet-Production Rates in Deuteron-Gold Collisions at √[s(NN)]=200 GeV

Jet production rates are measured in p+p and d+Au collisions at sqrt[s_{NN}]=200  GeV recorded in 2008 with the PHENIX detector at the Relativistic Heavy Ion Collider. Jets are reconstructed using the R=0.3 anti-k_{t} algorithm from energy deposits in the electromagnetic calorimeter and charged tracks in multiwire proportional chambers, and the jet transverse momentum (p_{T}) spectra are corrected for the detector response. Spectra are reported for jets with 12<p_{T}<50  GeV/c, within a pseudorapidity acceptance of |η|<0.3. The nuclear-modification factor (R_{dAu}) values for 0%-100% d+Au events are found to be consistent with unity, constraining the role of initial state effects on jet production. However, the centrality-selected R_{dAu} values and central-to-peripheral ratios (R_{CP}) show large, p_{T}-dependent deviations from unity, challenging the conventional models that relate hard-process rates and soft-particle production in collisions involving nuclei.

Meta-analysis of the risk of small bowel obstruction following open or laparoscopic colorectal surgery

Background

One of the potential advantages of laparoscopic compared with open colorectal surgery is a reduction in postoperative bowel obstruction events. Early reports support this proposal, but accumulated evidence is lacking.

Methods

A systematic review and meta-analysis was performed of randomized clinical trials and observational studies by searching the PubMed and Cochrane Library databases from 1990 to August 2015. The primary outcomes were early and late postoperative bowel obstruction following laparoscopic and open colorectal surgery. Both ileus and bowel obstruction were defined as a postoperative bowel obstruction. Subgroup and sensitivity analyses were performed, and a random-effects model was used to account for the heterogeneity among the studies.

Results

Twenty-four randomized clinical trials and 88 observational studies were included in the meta-analysis; 106 studies reported early outcome and 12 late outcome. Collectively, these studies reported on the outcomes of 148 392 patients, of whom 58 133 had laparoscopic surgery and 90 259 open surgery. Compared with open surgery, laparoscopic surgery was associated with reduced rates of early (odds ratio 0·62, 95 per cent c.i. 0·54 to 0·72; P &lt; 0·001) and late (odds ratio 0·61, 0·41 to 0·92; P = 0·019) postoperative bowel obstruction. Weighted mean values for early postoperative bowel obstruction were 8 (95 per cent c.i. 6 to 10) and 5 (3 to 7) per cent for open and laparoscopic surgery respectively, and for late bowel obstruction were 4 (2 to 6) and 3 (1 to 5) per cent respectively.

Conclusion

The reduction in postoperative bowel obstruction demonstrates an advantage of laparoscopic surgery in patients with colorectal disease.

Effect of the Film-Growth Defects on the Magnetic Microstructure of Epitaxial FePt Thin Film

Effect of the columnar grain boundaries on the perpendicular magnetic domain structure of epitaxial L10 FePt (001) thin film has been studied using electron holography. The analysis of stray fields shows that both the continuous and columnar epitaxial films of L10 FePt (001) consist of perpendicular magnetic domain walls. In the columnar epitaxial film, however, the perpendicular domain walls tend to be confined to columnar grain boundaries, because columnar boundaries act as pinning sites for the domain walls. The domain wall pinning by columnar grain boundaries leads to a significant hysteresis effect in the perpendicular magnetization of L10 FePt epitaxial films.

Measurements of Elliptic and Triangular Flow in High-Multiplicity 3He+Au Collisions at √(s(NN))=200 GeV

We present the first measurement of elliptic (v(2)) and triangular (v(3)) flow in high-multiplicity (3)He+Au collisions at √(s(NN))=200  GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in (3)He+Au and in p+p collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the (3)He+Au system. The collective behavior is quantified in terms of elliptic v(2) and triangular v(3) anisotropy coefficients measured with respect to their corresponding event planes. The v(2) values are comparable to those previously measured in d+Au collisions at the same nucleon-nucleon center-of-mass energy. Comparisons with various theoretical predictions are made, including to models where the hot spots created by the impact of the three (3)He nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems.

Reliability and validity of lower extremity computed tomography as a screening tool for osteoporosis

We evaluated the correlation between central bone mineral density (BMD) and peripheral bone attenuation using lower extremity computed tomography (CT). A good correlation was found between lower extremity CT and central BMD suggesting that CT is useful for screening osteoporosis, and that peripheral bone attenuation adequately reflects central BMD.

INTRODUCTION

This study aimed to evaluate the reliability and validity of CT as a screening tool for osteoporosis and to estimate the correlation between central BMD and peripheral bone attenuation using lower extremity CT.

METHODS

In total, 292 patients who underwent a lower extremity, lumbar spine, or abdomen and pelvic CT scan within a 3-month interval of a dual-energy X-ray absorptiometry (DEXA) examination were included. Following reliability testing, bone attenuation of the L1, L2, L3, L4, femoral head, femoral neck, greater trochanter, distal femur, proximal tibia, distal tibia, and talus was measured by placing a circular region of interest on the central part of each bony region on a coronal CT image. Partial correlation was used to assess the correlation between CT and DEXA after adjusting for age and body mass index.

RESULTS

In terms of reliability, all bone attenuation measurements, except the femoral neck, showed good to excellent interobserver reliability (intraclass correlation coefficients, 0.691-0.941). In terms of validity, bone attenuation of the L1 to L4, femoral neck, and greater trochanter on CT showed significant correlations with BMD of each area on DEXA (correlation coefficients, 0.399-0.613). Bone attenuation of the distal tibia and talus on CT showed significant correlations with BMD of all parts on DEXA (correlation coefficients, 0.493-0.581 for distal tibia, 0.396-0.579 for talus).

CONCLUSION

Lower extremity CT is a useful screening tool for osteoporosis, and peripheral bone attenuation on lower extremity CT adequately reflects central BMD on DEXA.

The effect of horse simulator riding on visual analogue scale, body composition and trunk strength in the patients with chronic low back pain

BACKGROUND

Chronic low back pain (CLBP) is one of the most common musculoskeletal disorders, and thus effective treatments are required. Recently, real horseback riding has been reported to be beneficial for the patients. However, it has some limitations, such as limited approaches and safety issues.

OBJECTIVE

The purpose of this study was to investigate the effect of horse simulator riding on back pain, body composition and trunk strength in the patients with CLBP.

PARTICIPANTS

Forty-seven men with CLBP (mean age 20.55 ± 1.38 years) were randomly divided into a control group (n = 23) and a horse simulator riding group (n = 24), and visual analogue scale (VAS), body composition and isokinetic trunk strength were measured after 8 weeks for which subjects in a horse simulator riding group had performed the horse simulator exercise (HSE).

RESULTS

Horse simulator exercise significantly reduced pain scores of VAS and enhanced isokinetic torques of trunk at 30 and 90°/s. There were also significantly increased muscle mass and decreased fat mass in horse simulator riding group.

CONCLUSION

It can be inferred that HSE may be helpful in relief of back pain and recovery of back function through developing trunk strength and balancing the ratio of trunk flexor/extensor muscles.

Use of permanent marker to deposit a protection layer against FIB damage in TEM specimen preparation

Permanent marker deposition (PMD), which creates permanent writing on an object with a permanent marker, was investigated as a method to deposit a protection layer against focused ion beam damage. PMD is a simple, fast and cheap process. Further, PMD is excellent in filling in narrow and deep trenches, enabling damage-free observation of high aspect ratio structures with atomic resolution in transmission electron microscopy (TEM). The microstructure, composition, gap filling ability and planarization of the PMD layer were studied using dual beam focused ion beam, transmission electron microscopy, energy dispersive X-ray spectroscopy and electron energy loss spectroscopy. It was found that a PMD layer is basically an amorphous carbon structure, and that such a layer should be at least 65 nm thick to protect a surface against 30 keV focused ion beam damage. We suggest that such a PMD layer can be an excellent protection layer to maintain a pristine sample structure against focused ion beam damage during transmission electron microscopy specimen preparation.

Management of traumatic labral tear in acetabular fractures with posterior wall component

BACKGROUND

Posterior labral tear is frequently encountered in acetabular fractures with posterior wall component (AFPWC). However, there has been very little information in the literature on the type and management of traumatic labral tears in AFPWC.

HYPOTHESIS

Traumatic labral tear is a constant intracapsular injury in AFPWC and can be repaired using adequate methods according to its type and size.

MATERIALS AND METHODS

A retrospective study of 14 patients (mean age 38 years [16-58]) who underwent open surgery for AFPWC was conducted using prospectively collected data. The types of posterior labral tear were investigated at intraoperative examination through the ruptured joint capsule or its extension, and were concomitantly managed. Surgical outcomes were clinically assessed using Merle d'Aubigné (PMA) score and Visual Analog Scale (VAS), and radiologically evaluated at final follow-up.

RESULTS

Posterior labral tears were present in all 14 patients. The types of labral tear were osseous avulsion and posterior root avulsion tear (n=9), longitudinal peripheral tear and posterior root avulsion tear (n=2), longitudinal peripheral tear (n=2), and osseous avulsion tear (n=1). All unstable labra in 12 patients (86%) were repaired. All avulsion tears of the posterior root were repaired using a suture anchor, longitudinal peripheral tears using suture fixation or/and suture anchors, and osseous avulsion tears using a spring plate. The mean PMA score and VAS were 16.4 (14-18) and 1.7 (0-3) at final follow-up, respectively. The radiologic grades at last follow-up were good or excellent in all patients.

DISCUSSION

All AFPWC in this study consistently revealed posterior labral tear. Posterior root avulsion tears accompanied with osseous avulsion was the most common type. Torn labra should be repaired as much as possible if unstable, considering the important functions of a normal labrum; fixation using a suture anchor may be useful for an avulsion tear of the posterior root.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Clinical characterization and molecular classification of 12 Korean patients with pseudohypoparathyroidism and pseudopseudohypoparathyroidism

CONTEXT

Pseudohypoparathyroidism (PHP) is defined as resistance toward parathyroid hormones. PHP and pseudopseudohypoparathyroidism (PPHP) are rare disorders resulting from genetic and epigenetic aberrations within or upstream of the GNAS locus. This study investigated the clinical characteristics and performed a molecular analysis of PHP and PPHP.

METHODS

A total of 12 patients with (P)PHP from 11 unrelated families (4 with PHP-Ia, 6 with PHP-Ib, and 2 with PPHP) were characterized using both clinical and molecular methods. Clinical features included the presenting symptoms, Albright hereditary osteodystrophy features, and resistance to hormones. Comprehensive analysis of the GNAS and STX16 loci was undertaken to investigate the molecular defects underlying (P)PHP.

RESULTS

All PHP-Ib patients displayed hypocalcemic symptoms. All PHP-Ia patients showed resistance toward TSH, in addition to PTH. In most patients with PHP, when the diagnosis of PHP was first established, hypocalcemia and hyperphosphatemia were associated with a significant increase in serum PTH levels. One patient with PHP-Ia was diagnosed with growth hormone deficiency and showed a good response to human recombinant growth hormone therapy. 6 patients with PHP-Ia and PPHP showed 5 different mutations in the GNAS gene. 5 patients with PHP-Ib displayed a loss of differentially methylated region (DMR) imprints of the maternal GNAS. One PHP-Ib patient showed a de novo microdeletion in STX16 and a loss of methylation of exon A/B on the maternal allele. No patients revealed paternal disomy among 4 patients with PHP-Ib.

CONCLUSIONS

Identification of the molecular causes of PHP and PPHP explains their distinctive clinical features and enables confirmation of the diagnosis and exact genetic counseling.