Bisphosphonate-Related Osteonecrosis of the Jaw.

OBJECTIVES: Antiresorptive agents for bone pain were widely used to treat patients with advanced osteoporosis, multiple myeloma, and bone metastatic cancer. In recent years, however, bisphosphonate-related osteonecrosis of the jaw (BRONJ) has been a rare but major complication of this therapy. Most patients with BRONJ undergo dental procedures during treatment with antiresorptive agents. However, BRONJ may also occur spontaneously. This study reports 13 BRONJ patient cases at Kaohsiung Veterans General Hospital, Taiwan, and their related treatments. We also compare patients with cancer with patients with osteoporosis in treatment outcomes. METHODS: Thirteen symptomatic patients with BRONJ were reviewed between 1985 and 2018 at Kaohsiung Veterans General Hospital. We included patients at advanced stage who were hospitalized for infection control of osteonecrosis of the jaw and excluded asymptomatic patients at stage 0 and stage 1. Four multiple myeloma, 3 patients with bone metastatic breast cancer and 6 patients with advanced osteoporosis (average ages, 63.57 ± 14.54 years in cancer patients and 79.5 ± 9.31 years in osteoporosis patients; average drug durations, 25.86 ± 27.23 months in cancer patients and 58.33 ± 23.87 months in osteoporosis patients; average follow-up times, 22.71 ± 14.46 months in cancer patients and 28.08 ± 36.35 months in osteoporosis patients) were included. RESULTS: Seven patients were defined as having stage 3 (53.8%) and 6 as having stage 2 (46.2%) medication-related osteonecrosis of the jaw, according to the American Association of Oral and Maxillofacial Surgeons classification. The complete response rate with totally healed mucosa was 61.5%. Four cancer patients received free fibular flap (FFF) reconstruction with a high complete response rate (100%). All of them had a relatively better performance status, and the average age was also younger than osteoporosis patients. CONCLUSION: Free fibular flap with a high complete response rate may improve pain relief and infection control for patients with BRONJ. Younger age is seemed to be a great indicator for FFF, but poor self-care ability (Eastern Cooperative Oncology Group status >3) is not suitable for these surgical treatments.

Haematogenous Klebsiella pneumoniae osteomyelitis.

OBJECTIVES: Klebsiella pneumoniae infection has been associated with alcoholic and diabetic patient populations, especially in Asian populations. K. pneumonia wound infection is common, but K. pneumonia without wound osteomyelitis (OM) is relatively rare. However, the pathogenesis of haematogenous K. pneumonia without open wound OM still unclear until now. In our research, we are trying to collect patients with haematogenous K. pneumonia osteomyelitis (K.p OM) at our hospital and to evaluate their contributing factors. METHODS: We compiled a retrospective database of haematogenous K. pneumonia osteomyelitis (K.p OM) from 1990 to 2019 at our hospital. Patients' bone cultures without K. pneumonia infection were excluded. Sixteen patients with haematogenous K.p OM were recruited. Patients' basic information, comorbidities, wound history, the biochemical examination of the blood, bacterial blood, bone, urine, and liver abscess cultures, the location of OM, corresponding treatments, and post operation K.p wound infection history were reviewed retrospectively. The collected data were analyzed using SPSS software. RESULTS: Unwounded haematogenous K.p OM had a statistically significant and positive correlation with liver insufficiency (P = .037; OR = 2.200), advanced age (≥ 65 years) (P = .037; OR = 2.200) and male gender (P = .03; OR = 1.833). DM, hypertension, steroid usage, GI or GU tract K.p infection, post operation K.p wound infection, hypoalbuminemia, and the location of K.p OM had no significant relationship to outcomes. CONCLUSION: Male patients of advanced age (> 65 years) and patients with liver insufficiency, including liver cirrhosis and hepatitis, have a strong correlation with unwounded haematogenous K.p OM.

Osteomyocutaneous Free Fibula Flap Prevents Osteoradionecrosis and Osteomyelitis in Head and Neck Cancer Reconstruction.

BACKGROUND: Osteoradionecrosis (ORN) is one of the most severe complications of free fibula reconstruction after radiotherapy. The gold standard treatment of osteomyelitis involves extensive debridement, antibiotics, and sufficiently vascularized muscle flap coverage for better circulation. Therefore, we hypothesized that free fibula flap with muscle could decrease the risk of ORN. METHODS: This study consisted of 85 patients who underwent reconstruction with free fibula flap in head and neck cancer by a single reconstructive surgeon at Kaohsiung Veterans General Hospital over a period of 19 years (1998-2016). Patients with postoperative adjuvant radiotherapy were included in the study and were grouped by either free fibula osteocutaneous flap or free fibula osteomyocutaneous flap (with flexor hallucis longus muscle), and the incidence of ORN was compared. RESULTS: Of the 85 patients, 15 were reconstructed with osteocutaneous fibula flap and 70 were with osteomyocutaneous fibula flap. The rate of ORN or osteomyelitis was significantly lower in the muscle group (18.6%, n = 13/70 vs. 46.7%, n = 7/15, p = 0.020, Chi-square test). CONCLUSION: Vascularized muscle transfer increases perfusion of surrounding tissues and the bone flap, thereby decreasing the incidence of osteomyelitis or osteonecrosis.

Risk of Free Flap Failure in Head and Neck Reconstruction: Analysis of 21,548 Cases From A Nationwide Database.

BACKGROUND: Head and neck reconstruction is complicated and is made even more challenging by free flap failure. We identified risk factors associated with free flap failure in records extracted from a nationwide database of a 23 million populations. METHODS: We used International Classification of Diseases, Ninth Version, codes 140 to 149 and 161 to identify patients in Taiwan's National Health Insurance Research Database with head and neck cancer between 2000 and 2013. Patient's age, sex, neoadjuvant treatment, comorbidities, and anticoagulation use were also retrieved. Free flap reconstruction twice, or free flap and pedicle flap reconstructions during the same hospitalization were recorded as free flap failure. Logistic regression was used to identify factors that increased risk of free flap failure. RESULTS: A total of 21,548 patients with head and neck cancer were identified; 883 (4.1%) experienced free flap failure. Use of aspirin, clopidogrel, urokinase, prostaglandin (PGE1), low-molecular-weight heparin, and operation time were associated with free flap failure. However, some potential confounders could not be identified from the database. CONCLUSIONS: Several statistically significant findings were prone to influence by potential confounders. The clinically applicable result was that longer operation time and preoperative chemotherapy could increase the likelihood of free flap failure. On the other hand, several factors were proved to be irrelevant to free flap failure.

Clinical Importance and Risk Factors for Postoperative Late-Onset Pneumonia After Major Oral Cancer Surgery With Microvascular Reconstruction.

BACKGROUND: Pulmonary complications are common among patients who have undergone major oral cancer surgery with microvascular reconstruction. Current literatures focused on early-onset pneumonia in the postoperative acute stage. In contrast, we are aiming to identify the clinical importance and the risk factors associated with late-onset pneumonia in oral cancer patients after acute stage. METHODS: In total, 195 patients were included from May 2014 to December 2016 and followed up for up to 1 year after surgery. Their medical histories were reviewed to identify the risk factors of late-onset pneumonia and outcome. Primary outcome was late-onset pneumonia. Other outcome measures included early-onset pneumonia, tumor recurrence, and death within 1 year after surgery. RESULTS: Patients with late-onset pneumonia have demonstrated a significantly higher rate of tumor recurrence (P < 0.001) and death within 1 year (P < 0.001). Independent risk factors of late-onset pneumonia identified were age (P = 0.031), previous radiotherapy (P = 0.017), postoperative radiotherapy (P = 0.002), flap size (P = 0.001), flap type other than osteocutaneous fibula flap (P = 0.009), and tumor recurrence (P < 0.001). CONCLUSIONS: Late-onset pneumonia can act as a warning sign for oral cancer patients who have received microsurgical reconstruction, for its high correlation with tumor recurrence and mortality rate.

Pioglitazone reversed the fructose-programmed astrocytic glycolysis and oxidative phosphorylation of female rat offspring.

Excessive maternal high-fructose diet (HFD) during pregnancy and lactation has been reported to cause metabolic disorders in the offspring. Whether the infant's brain metabolism is disturbed by maternal HFD is largely unknown. Brain energy metabolism is elevated dramatically during fetal and postnatal development, whereby maternal nutrition is a key factor that determines cellular metabolism. Astrocytes, a nonneuronal cell type in the brain, are considered to support the high-energy demands of neurons by supplying lactate. In this study, the effects of maternal HFD on astrocytic glucose metabolism were investigated using hippocampal primary cultures of female infants. We found that glycolytic capacity and mitochondrial respiration and electron transport chain were suppressed by maternal HFD. Mitochondrial DNA copy number and mitochondrial transcription factor A expression were suppressed by maternal HFD. Western blots and immunofluorescent images further indicated that the glucose transporter 1 was downregulated whereas the insulin receptor-α, phospho-insulin receptor substrate-1 (Y612) and the p85 subunit of phosphatidylinositide 3-kinase were upregulated in the HFD group. Pioglitazone, which is known to increase astrocytic glucose metabolism, effectively reversed the suppressed glycolysis, and lactate release was restored. Moreover, pioglitazone also normalized oxidative phosphorylation with an increase of cytosolic ATP. Together, these results suggest that maternal HFD impairs astrocytic energy metabolic pathways that were reversed by pioglitazone.

Time-resolved X-ray reflection phases of the nearly forbidden Si(222) reflection under laser excitation.

The covalent electron density, which makes Si(222) measurable, is subject to laser excitation. The three-wave Si(222)/(13 {\overline 1}) diffraction at 7.82 keV is used for phase measurements. It is found that laser excitation causes a relative phase change of around 4° in Si(222) in the first 100 ps of excitation and this is gradually recovered over several nanoseconds. This phase change is due to laser excitation of covalent electrons around the silicon atoms in the unit cell and makes the electron density deviate further from the centrosymmetric distribution.

Obliquely-arranged double skin paddles: A novel design to reconstruct extensive head and neck defects with a single fibula or peroneal flap.

OBJECTIVE: To reconstruct extensive head and neck defects usually necessitates double free flaps, which require a time-and-manpower-consuming surgical procedure. We present using a single fibula or peroneal flap with the novel design of obliquely-arranged double skin paddles to reconstruct an extensive head and neck defect. METHODS: From 1998 to 2016, eight patients with the age of 52.25 (35-71) years old had extensive head and neck defects after oral cancer ablation. All of the defects were through and through with the size of 16.25 (12-24) cm × 8.8 (4.5-11) cm. Six of the defects were due to buccal cancer. One was due to tongue cancer, and another one was due to gingiva cancer. All the defects were reconstructed with obliquely-arranged double-paddle free fibula or peroneal flaps. The long axis of the skin paddles was arranged at certain angle (30-45 degrees) to the long axis of lower leg, and the two separate skin paddles were used as the form of island flaps by isolating the cutaneous perforators to create a true chimeric flap. RESULTS: The skin paddle sizes were 14 cm × 3 cm-24 cm × 11 cm and 9.5 cm × 4.5 cm-13 cm × 8 cm. The average length of harvested fibula was 19 (10-30) cm. All of the eight flaps survived without obvious donor site morbidity. One patient had partial skin necrosis over recipient site, requiring surgical debridements and closure. One patient had superficial necrosis over the edge of outer skin paddle, which healed spontaneously. After the follow-up periods of 1 month to 3 year and 8 months, two patients died of sepsis. Six of them could resume soft diet and had no saliva drooling. The remaining two remained nasogastric diet and had saliva drooling. CONCLUSION: With the design of obliquely-arranged double paddles, we may maximize the harvested skin area of lateral lower leg to reconstruct an extensive head and neck defect with a single free flap.

The safety and benefit of using oxidized regenerated cellulose to position free flap pedicle in head and neck reconstruction.

BACKGROUND: Oxidized regenerated cellulose (ORC; Surgicel®; Ethicon, Neuchâtel, Switzerland) is an absorbable hemostatic agent used for hemostasis in operation, although some surgeons use it to position free flap pedicles. The increasing risk of vessel compromise is a huge concern. However, no scientific data to date demonstrate the safety and benefit of using ORC in microvascular surgery. In the present study, we compared the outcome of microvascular head and neck reconstruction with and without pedicle placement using ORC. MATERIALS AND METHODS: From January 2015 to December 2017, we reviewed patients undergoing microvascular surgery with free fibular osteocutaneous flap in our hospital. The patients were divided into the ORC group and non-ORC group and their baseline characteristics and outcomes were compared. RESULTS: In total, there were 27 patients in the ORC group and 67 in the non-ORC group. The non-ORC group had significantly higher cigarette consumption (70.4% vs. 89.6%; p = .022). The outcome of the ORC group was better regarding arterial thrombosis (0% vs. 3%), flap failure (0% vs. 4.5%), hematoma (7.4% vs. 10.4%), and wound complications (25.9% vs. 44.8%). The ORC group had a worse result than the non-ORC group for vein thrombosis (7.4% vs. 4.5%) and duration of hospitalization (24.111 days vs. 23.627 days). However, none of above results was significant. CONCLUSIONS: Though this study was underpowered to detect the differences, the results showed a trend toward better outcomes of flaps and wounds in the ORC group. It seems that using ORC in this field is safe and beneficial.

Oral pioglitazone ameliorates fructose-induced peripheral insulin resistance and hippocampal gliosis but not restores inhibited hippocampal adult neurogenesis.

Diet-associated insulin resistance (IR) is intimately correlated with the progression of metabolic syndrome and hippocampal dysfunction. Pioglitazone (PIO), a selective peroxisome proliferator-activated receptor gamma (PPARγ) agonist, has been applied to enhance insulin sensitivity. With limited permeability to blood-brain-barrier, it is unclear that whether oral PIO available to cure both the peripheral IR and the impairment in the hippocampus. We evaluated the levels of peripheral and hippocampal IR via the homeostatic model assessment of insulin resistance and hippocampal IRS-1/Akt phosphorylation, respectively, of Wistar Kyoto rats fed with a regular chew or high fructose diet (HFD) for 12weeks. Gavage with PIO (30mg/kg/day, 2weeks) significantly reduced the peripheral IR and reversed the level of hippocampal PPARγ. Moreover, HFD-activated microglia and astrocyte were effectively relieved by PIO. The suppressed brain-derived neurotrophic factor, CaMKIIα, and postsynaptic density protein 95 in the hippocampus were effectively reversed by PIO. However, the hippocampal IR and inhibition of adult neurogenesis in dentate gyrus were not restored by PIO. Together, PIO oral application may reverse the HFD-induced peripheral IR and maintain the existed neuronal circuit by ameliorating glial activation and enhancing synaptic density through BDNF but failed to restore adult neurogenesis in the hippocampus.

Relationship Between Xanthelasma Palpebrarum and Hyperlipidemia.

BACKGROUND: Xanthelasma palpebrarum is a common periorbital lesion that occurs in middle-aged woman. Dyslipidemia was strongly associated with the occurrence of xanthelasma. Different treatment methods for xanthelasma were applied with comparable results. MATERIALS AND METHODS: This was a retrospective chart review series performed at a single institute. The surgical pathology of 69 patients who received surgical excision from 1994 to 2012 was obtained. In addition, International Classification of Diseases, Ninth Revision, Clinical Modification code of xanthelasma (374.51) of 44 patients who underwent nonsurgical treatment at an outpatient department was acquired from 2006 to 2012. The serum lipid levels, comorbidities, recurrence, and treatment methods were obtained and analyzed with Statistical Analysis System (SAS) 9.4. RESULTS: Of a total of 113 identified patients, 50 had lipid profile data. Of these 50 patients, 25 (50%) had dyslipidemia, which is higher than general population in Taiwan. The recurrence rate was 17.5%, and there was no statistical difference in the recurrence rate between the different treatment methods. CONCLUSIONS: Xanthelasma was found to be associated with dyslipidemia. Thus, we recommend patients with xanthelasma to check their lipid profile and receive diet control and lipid-lowering medications for lipid abnormalities.

High-resolution monochromator using a high-efficiency single-mode x-ray resonator at Laue incidence.

We report a high-resolution and high-efficiency monochromator with energy resolution, ΔE/E∼2.08*10-7, utilizing a hard x-ray single-mode Fabry-Perot (FP) resonator at Laue incidence at 14.4388 keV. Instead of using multiple-crystal diffraction via several asymmetric-cut crystals, a 3 meV single-peak is generated from the interference of a Si-made two-plate cavity with a thickness of 70 µm and a gap of 45 µm, where a (0-40) Laue reflection is used to excite the backreflection (12 4 0) for the enhancement of the FP efficiency. Due to the large angular acceptance of (12 4 0) and (0-40), the energy tunability can be achieved by changing the incident angle into the resonator. The application of x-ray resonators at Laue incidence as a monochromator can be further implemented to x-ray optics.

A Novel Application of Double-Paddle Peroneal Chimeric Flap as External Sentinel Monitor in Hypopharyngeal Reconstruction.

OBJECTIVES: Monitoring the viability of buried free flaps in hypopharyngeal reconstruction is difficult. Various methods have been proposed to monitor these buried flaps, but limitations remain. METHOD: We present a method of using double-paddle chimeric peroneal flaps that permanently externalizes a flap skin paddle as a monitoring paddle in hypopharyngeal reconstructions. This study was performed in a medical center in southern Taiwan; between 2013 and 2015, 10 patients underwent double-paddle chimeric peroneal flap reconstruction in advanced stages of hypopharyngeal cancer. We retrospectively reviewed the medical records from these surgeries, searching for either short-term postoperative complications or long-term follow-up morbidity and researched relevant articles for comparisons with other monitoring methods. RESULTS: None of the 10 flaps underwent total loss. The rate of stenosis and that of fistula formation was 10%. The average postoperative hospital stay was 39 days. Six of 10 patients were able to resume at least a soft diet after reconstruction, and none of the patients experienced significant complications. CONCLUSIONS: The peroneal flap is a useful flap because it is thin and pliable, has minimal donor site morbidity in patients without peripheral vascular disease, and has the potential of multiple skin paddles so that one skin paddle can be used for monitoring the buried flap. Using this method, direct clinical monitoring is feasible, and early detection of vascular complications is possible. Furthermore, the drawbacks of using a monitoring paddle produced by a deepithelialized bridge can be avoided.

Contributing Factors for Complications and Outcomes in Patients With Snakebite: Experience in a Medical Center in Southern Taiwan.

OBJECTIVES: Snakebite usually results in various complications, such as significant soft tissue damage, infection, hematological, and neurological deficit. Surgical intervention, usually, is indicated in patients with tissue necrosis, infection, and compartment syndrome. To identify the contributing factors for complications and outcomes in different patients with snakebite so that outcomes can be evaluated and treatment of such patients can be initiated at the earliest. METHODS: Information was collected regarding age, sex, underlying disease, species of snake, and the course of treatment of the victims of snakebite who visited the emergency department of a medical center in southern Taiwan between 2004 and 2014. The data obtained were analyzed using SPSS 20.0. RESULTS: The bites from Taiwan cobra (Naja naja atra) significantly resulted in more complications than those from other snakes and required surgical intervention. The use of antivenin and antibiotics, immediate presentation to the hospital, and the location of the bite also were significant contributing factors. CONCLUSIONS: Taiwan cobra significantly results in higher possibility of prolonged hospitalization, operation, tissue necrosis, infection, and necrotizing fasciitis. Location of the bite, immediate presentation to the hospital, and use of antivenin and antibiotics affect the outcome of snakebite. Knowledge of these factors will help in a better management of patients with snakebite.

Double-paddle peroneal flap for extensive lip defect reconstruction.

INTRODUCTION: Today, reconstructive surgeons offer an array of options to reconstruct the lip defects. Herein we present our experience of using free double-paddle peroneal flaps for extensive lip defect reconstruction. PATIENTS AND METHODS: From 1996 to 2014, 16 patients with extensive lip defects after tumor ablation were included. Free double-paddle peroneal flaps were used for reconstructions. In terms of flap design, one skin paddle superiorly placed on the lateral lower leg was used to reconstruct intraoral defects, whereas the other was inferiorly located and was used to reconstruct extraoral defects. A part of the inner skin paddle was everted, and the suture line with the outer skin paddle became the new vermilion border. A portion of the outer skin paddle could be de-epithelized and tucked into the fold of the inner skin paddle, leading to greater fullness of the new lip. RESULTS: Skin paddle sizes were 10-15 cm × 3-13 cm and 4-10.5 cm × 2.5-10.5 cm. Venous thrombosis occurred in one patient but was salvaged, and one flap had superficial necrosis over the outer paddle that was conservatively treated. In the 0.5-33 month follow-up period, all patients were able to close their mouths without obvious drooling. CONCLUSION: Free double-paddle peroneal flap transfer could augment lip definition, deepen the labial vestibule, and provide an acute-angle oral commissure, leading to satisfactory oral competency and improved cosmetic results. Therefore, this technique may be considered a viable option for extensive lip defect reconstruction.

Peroneal Flap for Tongue Reconstruction.

Background For large tongue defects, reconstructive surgeons have devised a variety of feasible options, such as radial forearm free flap and anterolateral thigh (ALT) flap. In our institution, peroneal flap has been the workhorse flap for the soft tissue defect in head and neck reconstruction. We present our experience using peroneal flap in tongue reconstruction. Patients and Methods The study included 47 patients who had undergone tongue reconstructions with peroneal flaps after tumor resection. The size and location of the defect after tumor resection determined whether the peroneal flaps could be harvested as pure septocutaneous flaps to solely reconstruct the neotongue or to carry an additional muscle bulk to fill the adjacent defect. Retrospective chart review was used to look for postoperative complications and to perform functional assessments (which were also performed through telephone inquiry). Results Of the 47 patients, 3 (6%) had flap failure and 1 (2.1%) had partial flap necrosis. The hemiglossectomy group had better results than the total glossectomy group with respect to speech and diet, but neither of these results reached statistical significance (p = 1.0 for speech and p = 0.06 for diet). The results of the subtotal glossectomy group were better than those of the total glossectomy group with respect to diet (p = 0.03). No statistically significant differences were noted among the three groups with respect to cosmetic aspect (p = 0.64). Conclusions Considering its reasonable postoperative complication rates and functional results, peroneal flap can be considered a feasible option for tongue reconstruction.

Sapphire hard X-ray Fabry-Perot resonators for synchrotron experiments.

Hard X-ray Fabry-Perot resonators (FPRs) made from sapphire crystals were constructed and characterized. The FPRs consisted of two crystal plates, part of a monolithic crystal structure of Al2O3, acting as a pair of mirrors, for the backward reflection (0 0 0 30) of hard X-rays at 14.3147 keV. The dimensional accuracy during manufacturing and the defect density in the crystal in relation to the resonance efficiency of sapphire FPRs were analyzed from a theoretical standpoint based on X-ray cavity resonance and measurements using scanning electron microscopic and X-ray topographic techniques for crystal defects. Well defined resonance spectra of sapphire FPRs were successfully obtained, and were comparable with the theoretical predictions.

Hyperbaric Oxygen Therapy Alleviates Carbon Monoxide Poisoning-Induced Delayed Memory Impairment by Preserving Brain-Derived Neurotrophic Factor-Dependent Hippocampal Neurogenesis.

OBJECTIVE: To test the hypothesis that hyperbaric oxygen therapy ameliorates delayed cognitive impairment after acute carbon monoxide poisoning by promoting neurogenesis through upregulating the brain-derived neurotrophic factor in the hippocampus. DESIGN: Laboratory animal experiments. SETTING: University/Medical center research laboratory. SUBJECTS: Adult, male Sprague-Dawley rats. INTERVENTIONS: Rats were divided into five groups: (1) non-carbon monoxide-treated control, (2) acute carbon monoxide poisoning, (3) acute carbon monoxide poisoning followed by 7-day hyperbaric oxygen treatment, (4) carbon monoxide + hyperbaric oxygen with additional intracerebroventricular infusion of Fc fragment of tyrosine kinase receptor B protein (TrkB-Fc) chimera, and (5) acute carbon monoxide poisoning followed by intracerebroventricular infusion of brain-derived neurotrophic factor. Acute carbon monoxide poisoning was achieved by exposing the rats to carbon monoxide at 2,500 ppm for 40 minutes, followed by 3,000 ppm for 20 minutes. Hyperbaric oxygen therapy (at 2.5 atmospheres absolute with 100% oxygen for 60 min) was conducted during the first 7 days after carbon monoxide poisoning. Recombinant human TrkB-Fc chimera or brain-derived neurotrophic factor was infused into the lateral ventricle via the implanted osmotic minipump. For labeling of mitotic cells in the hippocampus, bromodeoxyuridine was injected into the peritoneal cavity. Distribution of bromodeoxyuridine and two additional adult neurogenesis markers, Ki-67 and doublecortin, in the hippocampus was evaluated by immunohistochemistry or immunofluorescence staining. Tissue level of brain-derived neurotrophic factor was assessed by enzyme-linked immunosorbent assay. Cognitive behavior was evaluated by the use of eight-arm radial maze. MEASUREMENTS AND MAIN RESULTS: Acute carbon monoxide poisoning significantly suppressed adult hippocampal neurogenesis evident by the reduction in number of bromodeoxyuridine-positive, Ki-67⁺, and doublecortin⁺ cells in the subgranular zone of the dentate gyrus. This suppression of adult neurogenesis by the carbon monoxide poisoning was appreciably alleviated by early treatment of hyperbaric oxygen. The hyperbaric oxygen treatment also promoted a sustained increase in hippocampal brain-derived neurotrophic factor level. Blockade of hippocampal brain-derived neurotrophic factor signaling with intracerebroventricular infusion of recombinant human TrkB-Fc chimera significantly blunted the protection by the hyperbaric oxygen on hippocampal neurogenesis; whereas intracerebroventricular infusion of brain-derived neurotrophic factor mimicked the action of hyperbaric oxygen and preserved hippocampal neurogenesis after acute carbon monoxide poisoning. Furthermore, acute carbon monoxide poisoning resulted in a delayed impairment of cognitive function. The hyperbaric oxygen treatment notably restored the cognitive impairment in a brain-derived neurotrophic factor-dependent manner. CONCLUSIONS: The early hyperbaric oxygen treatment may alleviate delayed memory impairment after acute carbon monoxide poisoning by preserving adult neurogenesis via an increase in hippocampal brain-derived neurotrophic factor content.

Spontaneous Extensor Tendon Rupture in the Rheumatoid Wrist: Risk Factors and Preventive Role of Extended Tenosynovectomy.

OBJECTIVE: Spontaneous extensor tendon rupture is often seen in rheumatoid arthritis (RA) patients, but the risk factors are not clearly defined. We therefore collected the data of RA patients with previous extensor tendon rupture and those with tenosynovitis and analyzed the relationship between extended tenosynovectomy and spontaneous extensor tendon rupture. METHODS: We retrospectively reviewed 17 spontaneous extensor tendon rupture episodes in 15 RA patients and 14 tenosynovitis episodes that required tenosynovectomy in 12 RA patients from 1997 to 2013. Correlations between the incidence of tendon rupture, X-ray findings, and clinical findings in the affected wrists before tendon rupture were analyzed statistically using the test for proportion. RESULTS: The following parameters were significantly correlated with spontaneous extensor tendon rupture: disease duration longer than 8 years, persistent tenosynovitis longer than 1 year duration, and Larsen grade greater than 4 (P = 0.02, 0.03, and 0.01, respectively). Dislocation of the distal end of the ulna, carpal collapse, and the scallop sign on X-ray contributed to a higher spontaneous extensor tendon rupture rate among RA patients (P = 0.01, 0.05, and 0.03, respectively). Extended tenosynovectomy was performed on 14 wrists in 12 RA patients with persistent tenosynovitis longer than 6 months, and Larsen grade did not deteriorate in this group compared with those who did not undergo the surgery. No spontaneous extensor tendon rupture occurred following the surgery. CONCLUSIONS: Risk factors of spontaneous extensor tendon rupture included disease duration longer than 8 years, persistent tenosynovitis longer than 1 year, and wrist Larsen grade greater than 4. Dislocation of the distal end of the ulna, carpal collapse, and the scallop sign on X-ray indicated a higher probability of extensor tendon rupture. Rheumatologists should consult with hand surgeons promptly to preserve hand function before tendon rupture. Prophylactic extended tenosynovectomy surgery to prevent more severe damage of extensor tendon should be recommended in patients who had the above risk factors.

Single-mode selection for hard x-ray cavity resonance.

Single-mode selection is realized for hard x-ray cavity resonance using a three-mirror crystal device. The developed device consists of two coupled Si Fabry-Perot resonators (FPRs) and uses (12 4 0) backward diffraction to reflect back and forth the incident 14.4388 keV x-ray beam. The coupling between the two cavities gives an effective single-mode spectrum with a bandwidth of 0.81 meV. This method can be used to enhance the longitudinal coherent length without affecting transverse coherence, and is potentially useful in generating nearly total coherent beams in synchrotron or free-electron laser facilities.