Usefulness of double plate fixation after failed ORIF for clavicle shaft fracture.

PURPOSE: We aimed to evaluate the clinical and radiological outcomes of double plate fixation for failed clavicle shaft fracture surgery. MATERIALS AND METHODS: We analyzed 14 patients who underwent double plate fixation due to plate failure after clavicle shaft fracture surgery from March 2016 to March 2021. The study used 3.5 mm locking compression plates for superior clavicle and anterior reconstruction in all patients. In addition, moldable allograft bone was used to fill the bone defect. Clinical and radiological evaluation was performed immediately, at 2 and 4 weeks, and 3, 6, 9, and 12 months postoperatively. The visual analog scale (VAS), University of California at Los Angeles (UCLA) shoulder scale, and American Shoulder and Elbow Surgeons (ASES) scores and range of motion of the shoulder were evaluated as clinical results. For radiological evaluation, anteroposterior, caudal, and cephalad views of both clavicles were used. Successful bone union was defined as complete adjoining of the fracture site through callus formation. RESULTS: Successful bone union was achieved in all patients, and the mean time to bone union was 16.7 ± 1.2 weeks (range, 12-24 weeks). Statistically significant improvement in forward flexion and external and internal rotation was observed from 135.5° ± 6.3, 45.2° ± 5.3, and 13° ± 2.3 preoperatively to 157.0° ± 9.3, 68.7° ± 6.3, and 9.8° ± 3.1 at the final follow-up, respectively. The VAS score improved from an average of 6.2 ± 2.8 preoperatively to 1.3 ± 0.7 at the final follow-up, which was statistically significant (P = 0.018). In addition, the ASES score significantly increased from a mean of 52.1 ± 6.3 points preoperatively to 83.6 ± 7.8 points at the final follow-up (P = 0.001). The average UCLA shoulder score was 16.7 ± 1.4 and 31.4 ± 2.2 points preoperatively and at the final follow-up, respectively, which was statistically significant (P = 0.001). CONCLUSION: Double plate fixation has shown good results after failed open reduction and internal fixation (ORIF) for clavicle shaft fractures. Therefore, in complicated situations after ORIF, double plate fixation is considered a surgical treatment option.

Socioeconomic and Other Risk Factors for Retear after Arthroscopic Surgery for Nontraumatic Rotator Cuff Tear.

Background and Objectives: Few studies have investigated the socioeconomic factors associated with retear after rotator cuff repair. This study aimed to identify the risk factors, including socioeconomic factors, for rotator cuff retear in patients who underwent arthroscopic rotator cuff repair. Materials and Methods: This retrospective study included 723 patients diagnosed with full-thickness rotator cuff tears who underwent arthroscopic rotator cuff repair from March 2010 to March 2021. The outcome variable was rotator cuff retear observed on postoperative magnetic resonance imaging or ultrasonography. Sex, age, obesity, diabetes, symptom duration, and tear size were the independent variables. Socioeconomic variables included occupation, educational level, type of medical insurance, and area of residence. We compared patients with and without retear and estimated the effects of the independent factors on retear risk. Results: The mean age of the patients, symptom duration, and tear size were 62.4 ± 8.0 years, 1.8 ± 1.7 years, and 21.8 ± 12.5 mm, respectively. The age, type of medical insurance, diabetes, tear size, and symptom duration differed significantly between patients with and without retearing (p < 0.05). Age, occupation, type of medical insurance, diabetes, initial tear size, and symptom duration significantly affected the risk of retear. Patients who performed manual labor had a significantly higher retear rate (p = 0.005; OR, 1.95; 95% CI, 1.23-3.11). The highest retear risk was seen in patients with Medicaid insurance (p < 0.001; OR, 4.34; 95% CI, 2.09-9.02). Conclusions: Age, initial tear size, and symptom duration significantly affect retear risk after arthroscopic rotator cuff repair. Occupation and type of medical insurance were also risk factors for retear. Socioeconomically vulnerable patients may be at a greater risk of retear. Proactive efforts are required to expand early access to medical care.

Effectiveness and Tolerability of Combination Pharmacotherapy With Stimulant and Non-Stimulant in Children With Attention Deficit Hyperactivity Disorder.

Objectives: This study aimed to investigate the effectiveness and safety of combining psychostimulants and nonstimulants for patients under treatment for attention deficit hyperactivity disorder (ADHD). Methods: The study included 96 patients aged 6-12 years who were diagnosed with ADHD, among whom 34 received combination pharmacotherapy, 32 received methylphenidate monotherapy, and 30 received atomoxetine monotherapy. Statistical analysis was conducted to compare treatment and adverse effects among groups and to analyze changes before and after combination pharmacotherapy. The difference between combination pharmacotherapy and monotherapy was investigated. Logistic regression analysis was used to identify the predictors of combination pharmacotherapy. Results: No significant differences were observed between the groups in terms of age or pretreatment scores. The most common adverse effect experienced by 32% of patients in the combination pharmacotherapy group was decreased appetite. Clinical global impression- severity score decreased significantly after combination pharmacotherapy. All three groups showed significant clinical global impression- severity score improvements over time, with no significant differences among them. The predictive factors for combination pharmacotherapy included the Child Behavior Checklist total score internalizing subscale. Conclusion: Combination pharmacotherapy with methylphenidate and atomoxetine is a relatively effective and safe option for patients with ADHD who do not respond to monotherapy.

The use of dual mobility acetabular cups in total hip replacement reduces dislocation rates in hip dysplasia patients.

Total hip replacement arthroplasty (THA) in hip dysplasia patients has a higher dislocation rate than in patients with simple hip osteoarthritis due to anatomical deformation. Therefore, to reduce postoperative THA dislocation is the challenge for arthroplasty surgeons. From 2015 to 2020, 1525 patients underwent THA performed by two surgeons at a single institution. A total of 152 patients involving 172 THAs were included. The patients were classified into dual-mobility (DM) and fixed-bearing (FB) acetabular cup groups. The occurrence of postoperative dislocation and functional evaluation of the hip joint, was analyzed before and after surgery using the modified Harris hip score(mHHS). There was no difference in the preoperative demographics and radiographic parameters between the groups. The incidence of postoperative hip dislocation was significantly lower in the DM group (DM 0% vs. FB 9.0%) (P value = 0.003). The mHHS showed no difference before surgery and after surgery (DM 91.80 vs FB 92.03). Treating hip dysplasia patients with THA using a dual-mobility acetabular cup can reduce postoperative dislocations, and could be used for the better management of these patients.

Skeletal Muscle-Specific Bis Depletion Leads to Muscle Dysfunction and Early Death Accompanied by Impairment in Protein Quality Control.

Bcl-2-interacting cell death suppressor (BIS), also called BAG3, plays a role in physiological functions such as anti-apoptosis, cell proliferation, autophagy, and senescence. Whole-body Bis-knockout (KO) mice exhibit early lethality accompanied by abnormalities in cardiac and skeletal muscles, suggesting the critical role of BIS in these muscles. In this study, we generated skeletal muscle-specific Bis-knockout (Bis-SMKO) mice for the first time. Bis-SMKO mice exhibit growth retardation, kyphosis, a lack of peripheral fat, and respiratory failure, ultimately leading to early death. Regenerating fibers and increased intensity in cleaved PARP1 immunostaining were observed in the diaphragm of Bis-SMKO mice, indicating considerable muscle degeneration. Through electron microscopy analysis, we observed myofibrillar disruption, degenerated mitochondria, and autophagic vacuoles in the Bis-SMKO diaphragm. Specifically, autophagy was impaired, and heat shock proteins (HSPs), such as HSPB5 and HSP70, and z-disk proteins, including filamin C and desmin, accumulated in Bis-SMKO skeletal muscles. We also found metabolic impairments, including decreased ATP levels and lactate dehydrogenase (LDH) and creatine kinase (CK) activities in the diaphragm of Bis-SMKO mice. Our findings highlight that BIS is critical for protein homeostasis and energy metabolism in skeletal muscles, suggesting that Bis-SMKO mice could be used as a therapeutic strategy for myopathies and to elucidate the molecular function of BIS in skeletal muscle physiology.

Rottlerin-Liposome Inhibits the Endocytosis of Feline Coronavirus Infection.

Rottlerin (R) is a natural extract from Mallotus philippensis with antiviral properties. Feline infectious peritonitis (FIP) is a fatal disease caused by feline coronavirus (FCoV) that is characterized by systemic granulomatous inflammation and high mortality. We investigated the antiviral effect of liposome-loaded R, i.e., rottlerin-liposome (RL), against FCoV. We demonstrated that RL inhibited FCoV replication in a dose-dependent manner, not only in the early endocytosis stage but also in the late stage of replication. RL resolved the low solubility issue of rottlerin and improved its inhibition efficacy at the cellular level. Based on these findings, we suggest that RL is worth further investigation as a potential treatment for FCoV.

[Brain-Gut-Microbiota Axis].

Patients frequently report that stress causes or exacerbates gastrointestinal (GI) symptoms, indicating a functional relationship between the brain and the GI tract. The brain and GI tract are closely related embryologically and functionally, interacting in various ways. The concept of the brain-gut axis was originally established in the 19th and early 20th centuries based on physiological observations and experiments conducted in animals and humans. In recent years, with the growing recognition that gut microbiota plays a vital role in human health and disease, this concept has been expanded to the brain-gut-microbiota axis. The brain influences the motility, secretion, and immunity of the GI tract, with consequent effects on the composition and function of the gut microbiota. On the other hand, gut microbiota plays an essential role in the development and function of the brain and enteric nervous system. Although knowledge of the mechanisms through which the gut microbiota influences distant brain function is incomplete, studies have demonstrated communication between these organs through the neuronal, immune, and endocrine systems. The brain-gut-microbiota axis is an essential aspect of the pathophysiology of functional GI disorders such as irritable bowel syndrome, and is also involved in other GI diseases, including inflammatory bowel disease. This review summarizes the evolving concept of the brain-gut-microbiota axis and its implications for GI diseases, providing clinicians with new knowledge to apply in clinical practice.

Porcine Reproductive and Respiratory Syndrome Virus Engineered by Serine Substitution on the 44th Amino Acid of GP5 Resulted in a Potential Vaccine Candidate with the Ability to Produce High Levels of Neutralizing Antibody.

N-linked glycans covering GP5 neutralizing epitopes of porcine reproductive and respiratory syndrome virus (PRRSV) have been proposed to act as a sheath blocking the production of neutralizing antibodies. Herein, we genetically engineered PRRSV with serine (S) substitution on the 44th asparagine (N) on the GP5 ectodomain of PRRSV-2 lineage-1. To evaluate the recombinant PRRSV, in vivo experiments were performed in piglets. The recombinant virus group showed no viremia until 42 days post-inoculation (dpi), and the rectal temperature and average daily weight gain were in the normal range at the same time point as the negative control group. On the 42 dpi, both groups were challenged with the wild-type virus. The recombinant PRRSV group showed lower rectal temperature, viremia, and the lung lesions than that of the negative control group for 19 days post-challenge (dpc). Additionally, the recombinant virus induced 4.50 ± 3.00 (log2) and 8.25 ± 0.96 (log2) of neutralizing antibody before and after challenge, respectively. Taken together, this study confirmed that N44S substitution can create an infectious PRRSV that strongly induces neutralizing antibodies. In addition, the vCSL1-GP5-N44S mutant that we produced was confirmed to have potential as a vaccine candidate, showing good safety and protective effects in pigs.

Factors associated with nonunion of the posttraumatic subtalar arthrodesis after displaced intra-articular calcaneal fractures.

BACKGROUND: This study investigated the incidence of and risk factors for nonunion in patients with posttraumatic subtalar arthrodesis (SA). METHODS: We retrospectively reviewed 165 posttraumatic SA cases. Nonunion was diagnosed at 6 months after surgery based on the findings of clinical evaluations, plain radiographs, and CT scans. Patient-specific factors and surgeon-specific factors were evaluated as potential risk factors. RESULTS: The overall nonunion rate was 13.3 % (22 of 165 cases). In the final multivariate logistic regression analysis, smoking (odds ratio [OR] = 3.64; 95 % confidence interval [CI] = 1.23-10.75), parallel screw configuration (OR = 5.70; 95 % CI = 1.62-20.06), and freeze dried iliac crest (OR = 9.16; 95 % CI = 2.28-36.79) were demonstrated as risk factors for nonunion of posttraumatic SA. CONCLUSION: Patients with a history of smoking, parallel screw configuration fixation, and those who received freeze dried iliac crest as an interpositional graft, had a significantly higher rate of nonunion.

Comparison of Intravascular Uptake Using Touhy or Quincke Needle During Lumbar Medial Branch Block.

BACKGROUND: Inadvertent intravascular injection of local anesthetics can lead to false negative results following a lumbar medial branch block (MBB) performed to diagnose facet joint origin pain. A previous study demonstrated that the type of needle could affect the incidence of intravascular injection rates. OBJECTIVES: The primary endpoint of this study was to compare the incidence of intravascular injection during lumbar MBB between the Quincke and Touhy needles. The secondary endpoint of this study was to compare the injection time, radiation dose, and patient discomfort during lumbar MBB between the needle types. STUDY DESIGN: Prospective randomized trial. SETTING: An interventional pain management practice in South Korea. METHODS: The incidence of intravascular uptake of contrast medium was compared using the Touhy and Quincke needles under real-time fluoroscopy during lumbar MBB. Injection time, radiation dose, and patient discomfort during lumbar MBB were also compared. RESULTS: The incidence of intravascular injection was 21.8% (21/102) in the Touhy needle group and 21.2% (22/99) in the Quincke needle group. The odds ratio for the association between the needle types and intravascular injection was 1.1. The injection time, radiation dose, and patient discomfort during lumbar MBB were similar between the Touhy and Quincke needle groups. LIMITATIONS: This study was performed from L2 to L4 MBB of the unilateral lumbar region. Although the type of needle assigned to the patient was randomized, 3 needles, which are used for 3 levels of MBB, were identical. CONCLUSIONS: The overall incidence rate of intravascular injection during lumbar MBB was nearly 20% under real-time fluoroscopy for both types of needle. Use of the Touhy needle did not reduce the intravascular injection rate nor the injection time, radiation dose, and patient discomfort.

Low-dose clozapine monotherapy for recurrent non-suicidal self-injury: A case report.

Non-suicidal self-injury (NSSI) is a challenging issue in clinical settings. In the present case series, we report two female adolescents with recurrent depression and NSSI. Numerous approaches, such as anti-depressants, anti-psychotics, and even electroconvulsive therapy, were not effective. Clozapine has been implemented in a broad spectrum of psychiatric disorders, particularly refractory depression, impulse control problems, suicidal ideation, and NSSI. With a low dose (12.5-25 mg) of clozapine, the depressive symptoms and NSSI remarkably improved, and the improvement was sustained over four months after discharge. Low-dose clozapine monotherapy may be a treatment option with refractory depression and NSSI.

Development of a Chimeric Porcine Reproductive and Respiratory Syndrome Virus (PRRSV)-2 Vaccine Candidate Expressing Hypo-Glycosylated Glycoprotein-5 Ectodomain of Korean Lineage-1 Strain.

Vaccination is a practical method to provide protection against porcine reproductive and respiratory syndrome virus (PRRSV), but current PRRSV vaccines show limited efficacy against divergent field strains. Lineage 1 PRRSV includes virulent strains such as NADC30 and MN184 and now has become one of the most prevalent viruses in Korea. Accordingly, there is an urgent need to develop a new vaccine for Korean lineage-1 strains. In this study, a vaccine candidate against Korean lineage-1 PRRSV, vCSL1-GP5-N33D, was developed by reverse genetics technology. vCSL1-GP5-N33D was designed as a hypo-glycosylated chimeric virus containing the glycoprotein 5 ectodomain region of the Korean lineage-1 wild-type strain. An inactivated vaccine of vCSL1-GP5-N33D was applied to a PRRS-endemic farm and elicited high serum virus neutralization (SVN) antibody titers. The vaccinated group induced SVN antibody titers of 4.40 (log2) ± 2.46, which were approximately 2-fold higher than those of the negative control at 8-weeks post-vaccination. Moreover, 60% of pigs in the vaccinated group displayed SVN antibody titers of ≥5 (log2), while none of the pigs in the negative control exhibited SVN antibody titers of ≥5 (log2). The overall results of the animal experiment suggest that the vCSL1-GP5-N33D inactivated vaccine is a promising vaccine candidate.

Determining the etiology of small bowel obstruction in patients without intraabdominal operative history: a retrospective study.

PURPOSE: Most of the causes of small bowel obstruction (SBO) in patients without a history of abdominal surgery are unclear at initial assessment. This study was conducted to identify the etiology and clinical characteristics of SBO in virgin abdomens and discuss the proper management. METHODS: A retrospective review involving operative cases of SBO from a single institute, which had no history of abdominal surgery, was conducted between January 2010 and December 2020. Clinical information, including radiological, operative, and pathologic findings, was investigated to determine the etiology of SBO. RESULTS: A total of 55 patients were included in this study, with a median age of 57 years and male sex (63.6%) constituting the majority. The most frequently reported symptoms were abdominal pain and nausea or vomiting. Neoplasm as an underlying cause accounted for 34.5% of the cases, of which 25.5% were malignant cases. In patients aged ≥60 years (n=23), small bowel neoplasms were the underlying cause in 12 (52.2%), of whom 9 (39.1%) were malignant cases. Adhesions and Crohn disease were more frequent in patients aged <60 years. Coherence between preoperative computed tomography scans and intraoperative findings was found in 63.6% of the cases. CONCLUSION: There were various causes of surgical cases of SBO in virgin abdomens. In older patients, hidden malignancy should be considered as a possible cause of SBO in a virgin abdomen. Patients with symptoms of recurrent bowel obstruction who have no history of prior abdominal surgery require thorough medical history and close follow-up.

Paradoxical paramagnetic calcifications in the globus pallidus: An ex vivo MR investigation and histological validation study.

MR images based on phase contrast images have gained clinical interest as an in vivo tool for assessing anatomical and histological findings. The globus pallidus is an area of major iron metabolism and storage in the brain tissue. Calcium, another important metal in the body, is frequently deposited in the globus pallidus as well. Recently, we observed dense paramagnetic deposition with paradoxical calcifications in the globus pallidus and putamen. In this work, we explore detailed MR findings on these structures, and the histological source of the related findings using ex vivo CT and MR images. Ex vivo MR was obtained with a maximum 100 µm3 isotropic resolution using a 15.2 T MR system. 3D gradient echo images and quantitative susceptibility mapping were used because of their good sensitivity to metallic deposition, high signal-to-noise ratio, and excellent contrast to iron and calcium. We found dense paramagnetic deposition along the perforating arteries in the globus pallidus. This paramagnetic deposition was hyperdense on ex vivo CT scans. Histological studies confirmed this finding, and simultaneous deposition of iron and calcium, although more iron dominant, was observed along the vessel walls of the globus pallidus. This was an exclusive finding for the penetrating arteries of the globus pallidus. Thus, our results suggest that several strong and paradoxical paramagnetic sources at the globus pallidus can be associated with vascular degeneration.

Direct Measurement of ATP7B Peptides Is Highly Effective in the Diagnosis of Wilson Disease.

BACKGROUND & AIMS: Both existing clinical criteria and genetic testing have significant limitations for the diagnosis of Wilson disease (WD), often creating ambiguities in patient identification and leading to delayed diagnosis and ineffective management. ATP7B protein concentration, indicated by direct measurement of surrogate peptides from patient dried blood spot samples, could provide primary evidence of WD. ATP7B concentrations were measured in patient samples from diverse backgrounds, diagnostic potential is determined, and results are compared with biochemical and genetic results from individual patients. METHODS: Two hundred and sixty-four samples from biorepositories at 3 international and 2 domestic academic centers and 150 normal controls were obtained after Institutional Review Board approval. Genetically or clinically confirmed WD patients with a Leipzig score >3 and obligate heterozygote (carriers) from affected family members were included. ATP7B peptide measurements were made by immunoaffinity enrichment mass spectrometry. RESULTS: Two ATP7B peptides were used to measure ATP7B protein concentration. Receiver operating characteristics curve analysis generates an area under the curve of 0.98. ATP7B peptide analysis of the sequence ATP7B 887 was found to have a sensitivity of 91.2%, specificity of 98.1%, positive predictive value of 98.0%, and a negative predictive value of 91.5%. In patients with normal ceruloplasmin concentrations (>20 mg/dL), 14 of 16 (87.5%) were ATP7B-deficient. In patients without clear genetic results, 94% were ATP7B-deficient. CONCLUSIONS: Quantification of ATP7B peptide effectively identified WD patients in 92.1% of presented cases and reduced ambiguities resulting from ceruloplasmin and genetic analysis. Clarity is brought to patients with ambiguous genetic results, significantly aiding in noninvasive diagnosis. A proposed diagnostic score and algorithm incorporating ATP7B peptide concentrations can be rapidly diagnostic and supplemental to current Leipzig scoring systems.

The Impact of Emotional Exhaustion on Psychological Factors in Workers with Secondary Traumatic Experiences: A Multi-Group Path Analysis.

OBJECTIVE: The objective of the present study was to explore causal pathways to understand how second traumatic experiences could affect the development of emotional exhaustion and psychiatric problems. METHODS: A total of 582 workers who had jobs vulnerable to secondary traumatic experiences were enrolled for this study. Emotional exhaustion, secondary trauma, resilience, perceived stress, depression, anxiety, and sleep problems were evaluated. A model with pathways from secondary traumatic experience score to depression and anxiety was proposed. The participants were divided into three groups according to the resilience: the low, middle and high resilience group. RESULTS: Resilience was a meaningful moderator between secondary traumatic experiences and psychiatric problems. In the path model, the secondary trauma and perceived stress directly and indirectly predicted perceived stress, emotional exhaustion, depression, anxiety, and sleep problems in all three groups. Direct effects of perceived stress on depression and anxiety were the largest in the low resilience group. However, direct effects of secondary trauma on perceived stress and emotional exhaustion were the largest in the high resilience group. CONCLUSION: Understanding the needs of focusing for distinct psychological factors offers a valuable direction for the development of intervention programs to prevent emotional exhaustion among workers with secondary traumatic experiences.

Fermi-crossing Type-II Dirac fermions and topological surface states in NiTe2.

Transition-metal dichalcogenides (TMDs) offer an ideal platform to experimentally realize Dirac fermions. However, typically these exotic quasiparticles are located far away from the Fermi level, limiting the contribution of Dirac-like carriers to the transport properties. Here we show that NiTe2 hosts both bulk Type-II Dirac points and topological surface states. The underlying mechanism is shared with other TMDs and based on the generic topological character of the Te p-orbital manifold. However, unique to NiTe2, a significant contribution of Ni d orbital states shifts the energy of the Type-II Dirac point close to the Fermi level. In addition, one of the topological surface states intersects the Fermi energy and exhibits a remarkably large spin splitting of 120 meV. Our results establish NiTe2 as an exciting candidate for next-generation spintronics devices.

Assessing the Association Between Emotional Labor and Presenteeism Among Nurses in Korea: Cross-sectional Study Using the 4th Korean Working Conditions Survey.

BACKGROUND: Presenteeism has emerged as an important health-related issue and has been studied in a variety of occupation groups. This study examines the relationship between emotional labor and presenteeism in nurses in Republic of Korea. METHODS: As a cross-sectional study, our study was conducted on 328 female nurses participating in the fourth Korean Working Conditions Survey (2015). Nurses were identified by the Korean Industry Classification Code. Multivariable logistic regression analysis was performed to explore the association between emotional labor and presenteeism. RESULTS: Female nurses who always or sometimes hide their emotions in the workplace were found to have a high risk for presenteeism compared with female nurses who rarely hide their emotions in the workplace {odds ratio [OR] = 2.40 [95% confidence interval (CI) 1.04-5.54]; OR = 4.12 [95% CI 1.72-9.84], respectively}. Furthermore, the risk of presenteeism was higher in nurses who sometimes engaged with complaining customers compared with nurses who rarely did so, but it lacked statistical significance. CONCLUSION: Presenteeism in nurses can cause various negative secondary effects; therefore, an alternative should be sought to mediate nurses' emotional labor to prevent presenteeism.

The Management of Retained Rectal Foreign Body.

PURPOSE: Because insertion of a foreign body (FB) into the anus is considered a taboo practice, patients with a retained rectal FB may hesitate to obtain medical care, and attending surgeons may lack experience with removing these FBs. We performed this study to evaluate the clinical characteristics of Korean patients with a retained rectal FB and propose management guideline for such cases based on our experience. METHODS: We retrospectively investigated 14 patients between January 2006 and December 2018. We assessed demographic features, mechanism of FB insertion, clinical course between diagnosis and management, and outcomes. RESULTS: All patients were male (mean age, 43 years) and presented with low abdominal pain (n = 2), anal bleeding (n = 2), or concern about a retained rectal FB without symptoms (n = 10). FB insertion was most commonly associated with sexual gratification or anal eroticism (n = 11, 78.6%). All patients underwent general anesthesia for anal sphincter relaxation with the exception of 2 who underwent FB removal in the emergency department. FBs were retrieved transanally using a clamp (n = 2), myoma screw (n = 1), clamp application following abdominal wall compression (n = 2), or laparotomy followed by rectosigmoid colon milking (n = 2). Colotomy and primary repair were performed in four patients, and Hartmann operation was performed in one patient with fecal peritonitis. No morbidity or mortality was reported. All patients refused postextraction anorectal functional and anatomical evaluation and psychological counseling. CONCLUSION: Retained rectal FB is rare; however, colorectal surgeons should be aware of the various methods that can be used for FB retrieval and the therapeutic algorithm applicable in such cases.

Black phosphorus as a bipolar pseudospin semiconductor.

Semiconductor devices rely on the charge and spin of electrons, but there is another electronic degree of freedom called pseudospin in a two-level quantum system1 such as a crystal consisting of two sublattices2. A potential way to exploit the pseudospin of electrons in pseudospintronics3-5 is to find quantum matter with tunable and sizeable pseudospin polarization. Here, we propose a bipolar pseudospin semiconductor, where the electron and hole states have opposite net pseudospin polarization. We experimentally identify such states in anisotropic honeycomb crystal-black phosphorus. By sublattice interference of photoelectrons, we find bipolar pseudospin polarization greater than 95% that is stable at room temperature. This pseudospin polarization is identified as a consequence of Dirac cones merged in the highly anisotropic honeycomb system6,7. The bipolar pseudospin semiconductor, which is a pseudospin analogue of magnetic semiconductors, is not only interesting in itself, but also might be useful for pseudospintronics.