Transpedicular Intravertebral Cage Augmentation Using Expandable Cage in Kummell Disease: Technical Note and Case Series.

OBJECTIVE: To demonstrate the surgical techniques for transpedicular intravertebral cage augmentation (TPICA) using an expandable cage for Kummell disease, which requires posterior surgical stabilization, and provide the preliminary surgical outcomes. METHODS: Six consecutive patients undergoing TPICA surgery using an expandable cage with a minimum 6-month follow-up were evaluated. Radiographic analysis to evaluate the local kyphosis angle, restoration ratio of anterior vertebral height of the index vertebra, and clinical outcomes including the Oswestry Disability Index, EuroQol 5-dimension instrument, and visual analog scale for back and leg pain, were compared between the preoperative and final follow-ups. RESULTS: All patients showed improvements in all clinical outcomes and were able to walk independently without support at the last follow-up. In radiographic evaluation, the mean preoperative restoration ratio of anterior vertebral height was 41.2 ± 15.6%, which increased postoperatively to 70.3 ± 20.5% (1.70 times) and 62.4 ± 20.0% at the last follow-up (1.51 times). The mean preoperative local kyphosis angle was 10.5 ± 14.8 and was corrected to 6.0 ± 10.0 at the last follow-up. A slight loss of correction was observed between the postoperative period and the last follow-up; however, there was no clinical significance. CONCLUSIONS: Expandable cages in TPICA may allow easier surgical manipulation for cage insertion around the pedicle entrance, minimizing damage to the fractured vertebral body's end plates while achieving satisfactory height restoration compared to static cages, and may also provide wider indications for TPICA surgery.

Safety and Efficacy Assessment of Red Ginseng Oil (RXGIN) in Men with Lower Urinary Tract Symptoms in a Randomized, Double-Blind, Placebo-Controlled Trial.

PURPOSE: The purpose of this study was to evaluate the efficacy and safety of red ginseng oil (RXGIN) in men with lower urinary tract symptoms. MATERIALS AND METHODS: Men aged between 40 and 75 years with a total International Prostate Symptom Score (IPSS) of 8 to 19 points were recruited from April 2020 to December 2020. Subjects were randomly assigned to either the RXGIN group or the control group in a 1:1 ratio and received either RXGIN or placebo daily for 12 weeks. For the primary outcome, changes in IPSS scores at 6 and 12 weeks from baseline were analyzed. The secondary outcomes were changes in International Index of Erectile Function (IIEF), maximum urinary flow rate, and post-void residual volume at weeks 6 and 12 compared to baseline. Urine analysis and blood tests were additionally performed for safety assessment. RESULTS: A total of 88 subjects (RXGIN group, 46; control group, 42) completed the study. The total IPSS and IPSS subscores (residual urine sensation, frequency, intermittency, urgency, weak stream, straining, nocturia, and quality of life) were significantly improved in the RXGIN group compared to the control group at weeks 6 and 12. Total IIEF and sexual desire were significantly improved in the RXGIN group at week 6 and week 12, respectively, but there were no significant changes in the level of serum testosterone or dihydrotestosterone. The serum prostate-specific antigen showed significant decrease at weeks 12. No serious adverse events leading to discontinuation of the study drug were observed in the RXGIN group. CONCLUSIONS: Red ginseng oil (RXGIN) appears to be safe and effective in improving lower urinary tract symptoms in men and may also improve some aspects of sexual function.

Short chain fatty acids facilitate protective immunity by macrophages and T cells during acute fowl adenovirus-4 infection.

Short chain fatty acids (SCFAs) are major gut metabolites that are involved in the regulation of dysfunction in immune responses, such as autoimmunity and cytokine storm. Numerous studies have reported a protective action of SCFAs against infectious diseases. This study investigated whether SCFAs have protective effect for immunity during fowl adenovirus-4 (FAdV-4) infection. We examined whether SCFA mixture (acetate, propionate, and butyrate) administration could protect against intramuscular challenge of a virulent viral strain. SCFA treatment promoted MHCII-expressing monocytes, the active form of T cells, and effector molecules in both peripheral and lymphoid tissues. It also boosted the production of immune molecules involved in pathogen elimination by intraepithelial lymphocytes and changed the intestinal microbial composition. We suggest that gut metabolites influence the gut microbial environment, and these changes stimulate macrophages and T cells to fight against the intramuscular challenge of FAdV-4.

Optimal dual-energy computed tomography scan parameters to detect small-sized urinary stones and their composition.

To investigate the optimal scanning parameters of dual-energy computed tomography (DECT), which can accurately determine sensitivity (the detectability of urinary stones) and accuracy (the composition matching of urinary stones), and to apply them to clinical trials. Fifteen urinary stones were chemically analyzed, and their chemical compositions were considered a reference standard with which we compared the uric acid (UA) and non-UA compositions determined using DECT. The urinary stones were placed inside a bolus and scanned with a dual-source CT scanner under various selected dual-energy conditions (A to X) using various solid water phantom thicknesses. These datasets were analyzed using the Siemens syngo.via software tool (integrated into the CT system) for matching the sensitivity and accuracy assessments. This study showed that 80% of the highest sensitivity (detection of urinary stones) and 92% of the highest accuracy (composition matching of urinary stones) were achieved under condition A (a collimation beam width setting of 2 × 32 × 0.6 mm, an automatic exposure control setting of 80/sn140 peak kilovoltage, and a slice thickness of 0.5/0.5 mm) (P < 0.05). Application of the DECT energy parameters presented in the study will help identify the sensitivity and accuracy of UA and non-UA stone analysis, even in patients with small-sized urinary stones and in conditions difficult for analysis.

ERdj5 protects goblet cells from endoplasmic reticulum stress-mediated apoptosis under inflammatory conditions.

Endoplasmic reticulum stress is closely associated with the onset and progression of inflammatory bowel disease. ERdj5 is an endoplasmic reticulum-resident protein disulfide reductase that mediates the cleavage and degradation of misfolded proteins. Although ERdj5 expression is significantly higher in the colonic tissues of patients with inflammatory bowel disease than in healthy controls, its role in inflammatory bowel disease has not yet been reported. In the current study, we used ERdj5-knockout mice to investigate the potential roles of ERdj5 in inflammatory bowel disease. ERdj5 deficiency causes severe inflammation in mouse colitis models and weakens gut barrier function by increasing NF-κB-mediated inflammation. ERdj5 may not be indispensable for goblet cell function under steady-state conditions, but its deficiency induces goblet cell apoptosis under inflammatory conditions. Treatment of ERdj5-knockout mice with the chemical chaperone ursodeoxycholic acid ameliorated severe colitis by reducing endoplasmic reticulum stress. These findings highlight the important role of ERdj5 in preserving goblet cell viability and function by resolving endoplasmic reticulum stress.

Cervi Parvum Cornu complex for men with lower urinary tract symptoms: a multicenter, randomized, double-blind, placebo-controlled trial.

Background: To evaluate the efficacy and safety of Cervi Parvum Cornu, Angelicae Gigantis Radix and Glycyrrhizae Radix complex (CAG) in men with moderate lower urinary tract symptoms (LUTS). Materials and methods: From November 2020 to January 2022, participants with International Prostate Symptom Score (IPSS) of 12-19 in two centers were recruited and randomize into three groups: a CAG 500 mg/day group (CAG 500), a CAG 1000 mg/day group (CAG 1000), and a placebo group (PG). They were treated for 12 weeks. The primary endpoint was change of IPSS at the end of study from baseline. Secondary end points included change of prostate specific antigen (PSA), testosterone, dihydrotestosterone (DHT), maximum urinary flow rate (Q max), post-void residual volume (PVR), International Index of Erectile Function (IIEF), and drug safety. Results: A total of 103 patients were able to finish the study according to the study protocol. Total IPSS and sub-scores (residual urine sensation, frequency, weak stream, hesistancy, nocturia, and quality of life) in CAG 500 and CAG 1000 were significantly improved at the 12th week compared to those of the PG. Changes of serum PSA, DHT, and testosterone levels at the 12th week from baseline did not show significant differences among the three groups. Q max and PVR changes did not show significant differences among the three groups either. Total IIEF and sub-scores (erectile function, orgasmic function, sexual desire, intercourse satisfaction) in CAG 1000 were significantly improved at 12th week compared to those in PG. No significant adverse events were found. Conclusions: CAG is well tolerated in patients with moderate LUTS. Treatment with CAG for 12 weeks has a therapeutic effect on moderate LUTS.

Acute Toxicity in the Rat Lung Induced by Intratracheal Instillation of Glycolic Acid.

BACKGROUND/AIM: Inhalation toxicity tests of glycolic acid, which is used in many household products, have been reported, but the pulmonary toxicity of glycolic-acid has not been confirmed. Here, the lung damage caused by glycolic acid was investigated in rats. MATERIALS AND METHODS: An intratracheal instillation test was performed with glycolic acid in male rats. Bronchoalveolar lavage fluid (BALF) and histopathological analysis were conducted to identify the pulmonary toxicities. RESULTS: Intratracheal instillation of glycolic acid caused weight loss in animals and increased the content of lactate dehydrogenase, total protein, polymorphonuclear neutrophils, and inflammatory cytokines in BALF. In addition, pulmonary edema, alveolar/interstitial inflammation, and necrosis and desquamation of bronchial/bronchiolar epithelia were confirmed via histopathological examination. CONCLUSION: Exposure to glycolic acid can be harmful and toxic to the lungs.

Pulmonary toxicity of sodium dichloroisocyanurate after intratracheal instillation in sprague-dawley rats.

In water, sodium dichloroisocyanurate (NaDCC), a source for chlorine gas generation, releases free available chlorine in the form of hypochlorous acid, a strong oxidizing agent. NaDCC has been used as a disinfectant in humidifiers; however, its inhalation toxicity is a concern. Seven-week-old rats were exposed to NaDCC doses of 100, 500, and 2500 µg·kg-1 body weight by intratracheal instillation (ITI) to investigate pulmonary toxicity. The rats were sacrificed at 1 d (exposure group) or 14 d (recovery group) after ITI. Despite a slight decrease in body weight after exposure, there was no statistically significant difference between the control and NaDCC-treated groups. A significant increase in the total protein level of the bronchoalveolar lavage fluid (BALF) was observed in the exposure groups. Lactate dehydrogenase leakage into the BALF increased significantly (p < 0.01) in the exposure groups; however, recovery was observed after 14 d. The measurement of cytokines in the BALF samples indicated a significant increase in interleukin (IL)-6 in the exposure group and IL-8 in the recovery group. Histopathological examination revealed inflammatory foci and pulmonary edema around the terminal bronchioles and alveoli. This study demonstrated that ITI of NaDCC induced reversible pulmonary edema and inflammation without hepatic involvement in rats.

Impact of age and metabolic syndrome-like components on prostate cancer development: a nationwide population-based cohort study.

BACKGROUND: Because of the contradictory results, more epidemiologic data is needed to determine if metabolic syndrome is a risk factor for developing prostate cancer. This study investigated whether metabolic syndrome-like components affect the incidence of prostate cancer in a Korean population. METHODS: Men over 50 years of age who underwent health examinations in 2009 were followed until December 2015 (n=1,917,430) using National Health Insurance System data. Subjects were divided into three groups according to the number of metabolic syndrome-like components. The predictive accuracy of age for prostate cancer was assessed by the Youden index and multivariate adjusted Cox regression analysis was used to analyze the effect of metabolic syndrome-like components on prostate cancer development. RESULTS: The risk of prostate cancer increases with age, and the best cutoff age for prostate cancer detection was 62 years (the maximum value of the Youden index). When stratified by the number of metabolic syndrome-like components, the age with the highest Youden index of each group is still 61 or 62 years. In multivariate adjusted Cox regression analysis, there was no statistically significant difference in the incidence rate among the non-component group, the group with 1 or 2 components, and the group with ≥3 components. CONCLUSIONS: The current study found that there was no statistically significant association between metabolic syndrome and prostate cancer development in a Korean population. However, results of this study should be interpreted with consideration due to several limitations including the diversity of definitions of metabolic syndrome components.

How Much Reliable Is the Current Belief on Grade Group 1 Prostate Cancer?

Objective: To evaluate the clinicopathological characteristics of grade group 1 (GG1) prostate cancer in Korean populations. Methods: We retrospectively analyzed 492 consecutive radical prostatectomy specimens from our institution, which included those from 322 men with clinical GG1 and 170 with clinical GG2 tumors between years 2009 and 2018. The incidence of Gleason score (GS) upgrading, extraprostatic extension (EPE), and seminal vesicle invasion (SVI) were evaluated in patients with clinical GG1. In pathological GG1 cases, the distribution of adverse pathological features including EPE, lymphovascular invasion (LVI), perineural invasion (PNI), and biochemical recurrence (BCR) was analyzed. Results: Altogether, 78 (24.2%) out of 322 men in the clinical GG1 group demonstrated upgrading of GS, including 19 men with pathological Gleason score 4 + 3 = 7 and 6 with ≥ pathological Gleason score 4 + 4 = 8 cases. EPE was found in 37 (11.5%) and 22 (8.9%) men in clinical GG1 and pathological GG1 group, respectively. The incidence of LVI and PNI in the pathological GG1 cases was 2.8% (n = 7) and 28.6% (n = 71), respectively. BCR was observed in 4 men in pathological GG1 T2 (n = 226) and 2 men in GG1 T3 (n = 22) group. When we compared the pathological features between pathological GG1 T3 vs. GG2 T2, there was no statistical differences in the incidence of LVI and PNI between the two groups. Conclusions: Contrary to the current concept that GG1 is almost always clinically insignificant, it seems that GG1 still possess its respectable position as a group of cancer with aggressiveness. These findings should be kept in mind when deciding on treatment options for prostate cancer patients in the Asian populations.

Comprehensive pulmonary toxicity assessment of cetylpyridinium chloride using A549 cells and Sprague-Dawley rats.

Cetylpyridinium chloride (CPC), a quaternary ammonium compound and cationic surfactant, is used in personal hygiene products such as toothpaste, mouthwash, and nasal spray. Although public exposure to CPC is frequent, its pulmonary toxicity has yet to be fully characterized. Due to high risks of CPC inhalation, we aimed to comprehensively elucidate the in vitro and in vivo toxicity of CPC. The results demonstrated that CPC is highly cytotoxic against the A549 cells with a half-maximal inhibitory concentration (IC50 ) of 5.79 µg/ml. Following CPC exposure, via intratracheal instillation (ITI), leakage of lactate dehydrogenase, a biomarker of cell injury, was significantly increased in all exposure groups. Further, repeated exposure of rats to CPC for 28 days caused a decrease in body weight of the high-exposure group and the relative weights of the lungs and kidneys of the high recovery group, but no changes were evident in the histological and serum chemical analyses. The bronchoalveolar lavage fluid (BALF) analysis showed a significant increase in proinflammatory cytokines interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α levels. ITI of CPC induced focal inflammation of the pulmonary parenchyma in rats' lungs. Our study demonstrated that TNF-α was the most commonly secreted proinflammatory cytokine during CPC exposure in both in vitro and in vivo models. Polymorphonuclear leukocytes in the BALF, which are indicators of pulmonary inflammation, significantly increased in a concentration-dependent manner in all in vivo studies including the ITI, acute, and subacute inhalation assays, demonstrating that PMNs are the most sensitive parameters of pulmonary toxicity.

Predicting Insignificant Prostate Cancer: Analysis of the Pathological Outcomes of Candidates for Active Surveillance according to the Pre-International Society of Urological Pathology (Pre-ISUP) 2014 Era Versus the Post-ISUP2014 Era.

PURPOSE: To analyze the difference in the prediction accuracy with an active surveillance (AS) protocol between two eras (pre-International Society of Urological Pathology [pre-ISUP]-2014 vs. post-ISUP2014). MATERIALS AND METHODS: We retrospectively analyzed 118 candidates for AS who underwent radical prostatectomy between 2009 and 2017. We divided our patients into two groups (group 1 [n=57], operation date 2009-2015; group 2 [n=61], operation date 2016-2017). Pathologic slides in group 1 were reviewed to distinguish men with cribriform pattern (CP) because the determination of Gleason scores in old era had been based on pre-ISUP2014 classification. Postoperative outcomes in the two eras were analyzed twice: first, all men in group 1 vs. group 2; second, the remaining men after excluding those with CPs in group 1 vs. group 2. RESULTS: The proportion of men with insignificant prostate cancer (iPCa) was significantly lower in group 1 than in group 2 (36.8% vs. 57.4%, p=0.040). After excluding 11 men with CPs from group 1, those remaining (46 men) were compared again with group 2. In this analysis, the proportion of men with iPCa was similar between the two groups (old vs. contemporary era: 41.3% vs. 57.4%, p=0.146). Nine of 11 men with CP had violated the criteria for iPCa in the earlier comparison. CONCLUSIONS: The accuracy of the AS protocol has been affected by the coexistence of CPs and pure Gleason 6 tumors in the pre-ISUP2014 era. We suggest to use only contemporary (post-ISUP2014) data to analyze the accuracy with AS protocols in future studies.

Balanced adhesion and cohesion of chitosan matrices by conjugation and oxidation of catechol for high-performance surgical adhesives.

Catechol-conjugated chitosan (CCs), used as tissue adhesive, wound dressing, and hemostatic materials, has been drawing much more attention. However, most CCs tissue adhesives exhibit poor adhesion strength, and few studies on optimization of cohesion and adhesion strength of CCs derivatives have been conducted. This work focused on the balance between cohesion and adhesion strength of catechol-conjugated chitosan (CCs) derivatives via different mechanisms of chemical and enzymatic conjugation. CCs derivatives were characterized regarding its mechanical property, cytotoxicity, platelet adhesion and wound healing test. Mechanical properties could be optimized by the degree of catechol substitution, pH and the presence of oxidizing agent, resulting in that the highest value of adhesive shear strength to the porcine tissue is 64.8 ± 5.7 kPa. In addition, CCs derivatives exhibit decreased toxicity and promoted in vivo wound healing effects as comparing to a commercially available adhesive (Dermabond®). All the results demonstrate that CCs derivatives can be used as well-optimized tissue adhesives as well as a hemostat.

In Vitro and In Vivo Evaluation of the Toxic Effects of Dodecylguanidine Hydrochloride.

The toxicity profiles of the widely used guanidine-based chemicals have not been fully elucidated. Herein, we evaluated the in vitro and in vivo toxicity of eight guanidine-based chemicals, focusing on inhalation toxicity. Among the eight chemicals, dodecylguanidine hydrochloride (DGH) was found to be the most cytotoxic (IC50: 0.39 µg/mL), as determined by the water soluble tetrazolium salts (WST) assay. An acute inhalation study for DGH was conducted using Sprague-Dawley rats at 8.6 ± 0.41, 21.3 ± 0.83, 68.0 ± 3.46 mg/m3 for low, middle, and high exposure groups, respectively. The levels of lactate dehydrogenase, polymorphonuclear leukocytes, and cytokines (MIP-2, TGF-ß1, IL-1ß, TNF-α, and IL-6) in the bronchoalveolar lavage fluid increased in a concentration-dependent manner. Histopathological examination revealed acute inflammation with necrosis in the nasal cavity and inflammation around terminal bronchioles and alveolar ducts in the lungs after DGH inhalation. The LC50 of DGH in rats after exposure for 4 h was estimated to be >68 mg/m3. Results from the inhalation studies showed that DGH was more toxic in male rats than in female rats. Overall, DGH was found to be the most cytotoxic chemical among guanidine-based chemicals. Exposure to aerosols of DGH could induce harmful pulmonary effects on human health.

Plasmacytoid dendritic cells regulate colitis-associated tumorigenesis by controlling myeloid-derived suppressor cell infiltration.

Toll-like receptor (TLR)3 and TLR7 are important for stimulating plasmacytoid dendritic cells (pDCs), which secrete type I interferon. Mice deficient for TLR3 and TLR7 (TLR3-/-TLR7-/-) reportedly exhibit deteriorated colitis because of impaired pDCs. However, the role of pDCs in tumorigenesis-associated inflammation progression has not been studied. We treated wild-type or TLR3-/-TLR7-/- mice with dextran sulfate sodium (DSS) and/or azoxymethane (AOM) and examined colon mucosa, measured body weight and colon length of mice, and examined pDC and myeloid-derived suppressor cell (MDSC) accumulation. Further, we depleted pDCs in AOM/DSS-treated wild-type mice by treating them with anti-PDCA-1 antibodies. We found that MDSCs significantly increased, while pDCs decreased in TLR3-/-TLR7-/- mice. Moreover, TLR3-/-TLR7-/- mice developed colitis-associated colon cancer following AOM/DSS treatment. Additionally, we showed that a defect in TLR7 of pDCs is responsible for the aggravation of colitis-associated colon cancer. Further, we showed that TLR7 ligand mitigates colitis-associated colon cancer. Collectively, our results demonstrate that gut pDCs play a crucial role in reducing colorectal cancer development via the regulation of infiltrating MDSCs.

Association between the neutrophil-to-lymphocyte ratio and intravesical prostatic protrusion in men with benign prostatic hyperplasia.

OBJECTIVE: To analyze the association between neutrophil-to-lymphocyte ratio (NLR) and intravesical prostatic protrusion (IPP) in men with benign prostatic hyperplasia. METHODS: Two hundred and fifty men aged >50 years who presented with lower urinary tract symptoms at our institution between 2014 and 2018 were analyzed. Pearson's method was used for analysis of the correlation between NLR and IPP. Multivariate logistic regression analysis was used to identify predictors of IPP. Further analysis according to total prostate volume (TPV) was performed. RESULTS: The NLR correlated positively with IPP (Pearson's r = 0.459, P < 0.001) and was an independent predictor of IPP ≥10 mm (odds ratio, 2.95; 95% confidence interval, 1.59-5.47; P = 0.0006). Among the 142 men with prostates <40 cm3 , mean NLR was 2.50 ± 0.71 in those with IPP ≥10 mm and 1.71 ± 0.57 in those with IPP < 10 mm (P < 0.001). The NLR differed significantly between those with a prostate <40 cm3 and IPP ≥10 mm and those with a larger prostate and IPP < 10 mm (2.50 ± 0.71 vs 2.07 ± 0.77, respectively; P = 0.020). CONCLUSIONS: NLR can be used as a surrogate marker for presence of IPP. Its clinical value would be especially important in men with a small prostate gland but high IPP. The NLR seemed to be more strongly correlated with IPP than with TPV.

Acute and 28-Day Repeated Inhalation Toxicity Study of Glycolic Acid in Male Sprague-Dawley Rats.

BACKGROUND/AIM: The use of glycolic acid is present in a variety of consumer products, including medicines, cleaners, cosmetics, and paint strippers. It has recently led to concerns about toxicity from inhalation exposure. Herein, the pulmonary toxicity of glycolic acid was investigated in rats. MATERIALS AND METHODS: We conducted acute (~458 mg/m3) and sub-acute (~49.5 mg/m3) inhalation tests to identify the potential toxicities of glycolic acid. RESULTS: Inhalation exposure to glycolic acid in the acute and subacute inhalation tests did not cause any specific changes in clinical examinations, including body weight, organ weight, hematology, serum biochemistry, and histopathology. The polymorphonuclear neutrophils (PMNs) and inflammatory cytokines in Bronchoalveolar lavage fluid (BALF) increased in rats exposed to single and repeated inhalations. In the sub-acute test, the changes induced by glycolic acid were minor or returned to normal during the recovery period. CONCLUSION: The No Observed Adverse Effect Concentration (NOAEC) for the nasal and pulmonary toxicity of glycolic acid was determined to be over 50 mg/m3 at the end of a 28-day inhalation test in male rats.

Clinical Outcomes and Factors Influencing These Outcome Measures Resulting in Success After Arthroscopic Transosseous Triangular Fibrocartilage Complex Foveal Repair.

PURPOSE: To analyze postoperative outcomes after arthroscopic transosseous triangular fibrocartilage complex (TFCC) foveal repair and identify factors affecting the clinical outcomes. METHODS: This study retrospectively enrolled patients who were treated for TFCC foveal tears by arthroscopic transosseous TFCC foveal repair. The diagnosis of TFCC foveal tear was made based on medical history, physical examination, and magnetic resonance imaging, with confirmation via arthroscopic examination. Outcome evaluation was completed at a minimum of 2 years postoperatively, and patients were classified into 2 groups according to the minimal clinically important difference of the Patient-Rated Wrist Evaluation. Various factors including age, sex, trauma history, body mass index, symptom duration, hand dominance, ulnar variance, subluxation of the distal radioulnar joint, preoperative pain score, and functional status, as well as the cross-sectional area (CSA) of the pronator quadratus (PQ) muscle, were retrospectively analyzed using both univariate and multivariate analyses. RESULTS: During the study period, 42 patients were treated for TFCC foveal tears. The functional status significantly improved after surgery. Overall, 27 and 15 patients showed good and poor functional outcomes, respectively, which were assessed according to the minimal clinically important difference of the Patient-Rated Wrist Evaluation. On univariate analysis, clinical outcomes were better in male patients (P = .035), younger patients (P = .022), and those with higher CSAs of the PQ muscles (P < .001). However, on multivariable logistic regression analysis, only a higher CSA of the PQ muscle was identified as an independent prognostic factor affecting clinical outcome after TFCC foveal repair (P = .004). CONCLUSION: Arthroscopic transosseous TFCC complex foveal repair led to satisfactory results. However, lower PQ muscle CSA on magnetic resonance imaging was the most independent prognostic factor negatively affecting clinical outcomes. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Inhalation toxicity of benzalkonium chloride and triethylene glycol mixture in rats.

Benzalkonium chloride (BAC), a disinfectant, and triethylene glycol (TEG), an organic solvent/sanitizer, are frequently combined in commercially available household sprays. To assess the respiratory effect of this combination, Sprague-Dawley rats were exposed to an aerosol containing BAC (0.5%, w/v) and TEG (10%, w/v) for up to 2 weeks in a whole-body inhalation chamber. BAC (4.1-4.5 mg/m3, sprayed from 0.5% solution) promoted pulmonary cell damage and inflammation as depicted by the increase in total protein, lactate dehydrogenase, polymorphonuclear leukocytes, and macrophage inflammatory protein-2 in the bronchoalveolar lavage fluid, whereas TEG (85.3-94.5 mg/m3, sprayed from 10% solution) did not affect the lung. Rats exposed to the BAC/TEG mixture for 2 weeks showed severe respiratory symptoms (sneezing, wheezing, breath shortness, and chest tightness), but no lung damage or inflammation was observed. However, significant ulceration and degenerative necrosis were observed in the nasal cavities of rats repeatedly exposed to the BAC/TEG mixture. The mass median aerodynamic diameters of the aqueous, BAC, TEG and BAC/TEG aerosols were 1.24, 1.27, 3.11 and 3.24 µm, respectively, indicating that TEG-containing aerosols have larger particles than those of the aqueous and BAC alone aerosols. These results suggest that the toxic effects of BAC and BAC/TEG aerosols on the different respiratory organs may be associated with the difference in particle diameter, since particle size is important in determining the deposition site of inhaled materials.

Evaluation of pulmonary toxicity of benzalkonium chloride and triethylene glycol mixtures using in vitro and in vivo systems.

Benzalkonium chloride (BAC) is a widely used disinfectant/preservative, and respiratory exposure to this compound has been reported to be highly toxic. Spray-form household products have been known to contain BAC together with triethylene glycol (TEG) in their solutions. The purpose of this study was to estimate the toxicity of BAC and TEG mixtures to pulmonary organs using in vitro and in vivo experiments. Human alveolar epithelial (A549) cells incubated with BAC (1-10 µg/mL) for 24 hours showed significant cytotoxicity, while TEG (up to 1000 µg/mL) did not affect cell viability. However, TEG in combination with BAC aggravated cell damage and inhibited colony formation as compared to BAC alone. TEG also exacerbated BAC-promoted production of reactive oxygen species (ROS) and reduction of glutathione (GSH) level in A549 cells. However, pretreatment of the cells with N-acetylcysteine (NAC) alleviated the cytotoxicity, indicating oxidative stress could be a mechanism of the toxicity. Quantification of intracellular BAC by LC/MS/MS showed that cellular distribution/absorption of BAC was enhanced in A549 cells when it was exposed together with TEG. Intratracheal instillation of BAC (400 µg/kg) in rats was toxic to the pulmonary tissues while that of TEG (up to 1000 µg/kg) did not show any harmful effect. A combination of nontoxic doses of BAC (200 µg/kg) and TEG (1000 µg/kg) promoted significant lung injury in rats, as shown by increased protein content and lactate dehydrogenase (LDH) activity in bronchoalveolar lavage fluids (BALF). Moreover, BAC/TEG mixture recruited inflammatory cells, polymorphonuclear leukocytes (PMNs), in terminal bronchioles and elevated cytokine levels, tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) in BALF. These results suggest that TEG can potentiate BAC-induced pulmonary toxicity and inflammation, and thus respiratory exposure to the air mist from spray-form products containing this chemical combination is potentially harmful to humans.