Ceria-Based Therapeutic Antioxidants for Biomedical Applications.

The growing interest in nanomedicine over the last 20 years has carved out a research field called "nanocatalytic therapy," where catalytic reactions mediated by nanomaterials are employed to intervene in disease-critical biomolecular processes. Among many kinds of catalytic/enzyme-mimetic nanomaterials investigated thus far, ceria nanoparticles stand out from others owing to their unique scavenging properties against biologically noxious free radicals, including reactive oxygen species (ROS) and reactive nitrogen species (RNS), by exerting enzyme mimicry and nonenzymatic activities. Much effort has been made to utilize ceria nanoparticles as self-regenerating antioxidative and anti-inflammatory agents for various kinds of diseases, given the detrimental effects of ROS and RNS therein that need alleviation. In this context, this review is intended to provide an overview as to what makes ceria nanoparticles merit attention in disease therapy. The introductory part describes the characteristics of ceria nanoparticles as an oxygen-deficient metal oxide. The pathophysiological roles of ROS and RNS are then presented, as well as their scavenging mechanisms by ceria nanoparticles. Representative examples of recent ceria-nanoparticle-based therapeutics are summarized by categorization into organ and disease types, followed by the discussion on the remaining challenges and future research directions.

Ceria-vesicle nanohybrid therapeutic for modulation of innate and adaptive immunity in a collagen-induced arthritis model.

Commencing with the breakdown of immune tolerance, multiple pathogenic factors, including synovial inflammation and harmful cytokines, are conjointly involved in the progression of rheumatoid arthritis. Intervening to mitigate some of these factors can bring a short-term therapeutic effect, but other unresolved factors will continue to aggravate the disease. Here we developed a ceria nanoparticle-immobilized mesenchymal stem cell nanovesicle hybrid system to address multiple factors in rheumatoid arthritis. Each component of this nanohybrid works individually and also synergistically, resulting in comprehensive treatment. Alleviation of inflammation and modulation of the tissue environment into an immunotolerant-favourable state are combined to recover the immune system by bridging innate and adaptive immunity. The therapy is shown to successfully treat and prevent rheumatoid arthritis by relieving the main symptoms and also by restoring the immune system through the induction of regulatory T cells in a mouse model of collagen-induced arthritis.

Comparing artificial intelligence to humans for endoscopic diagnosis of gastric neoplasia: An external validation study.

OBJECTIVES: Artificial intelligence (AI) uses deep learning functionalities that may enhance the detection of early gastric cancer during endoscopy. An AI-based endoscopic system for upper endoscopy was recently developed in Japan. We aim to validate this AI-based system in a Singaporean cohort. METHODS: There were 300 de-identified still images prepared from endoscopy video files obtained from subjects that underwent gastroscopy in National University Hospital (NUH). Five specialists and 6 non-specialists (trainees) from NUH were assigned to read and categorize the images into "neoplastic" or "non-neoplastic." Results were then compared with the readings performed by the endoscopic AI system. RESULTS: The mean accuracy, sensitivity, and specificity for the 11 endoscopists were 0.847, 0.525, and 0.872, respectively. These values for the AI-based system were 0.777, 0.591, and 0.791, respectively. While AI in general did not perform better than endoscopists on the whole, in the subgroup of high-grade dysplastic lesions, only 29.1% were picked up by the endoscopist rating, but 80% were classified as neoplastic by AI (P = 0.0011). The average diagnostic time was also faster in AI compared with endoscopists (677.1 s vs 42.02 s (P < 0.001). CONCLUSION: We demonstrated that an AI system developed in another health system was comparable in diagnostic accuracy in the evaluation of static images. AI systems are faster and not fatigable and may have a role in augmenting human diagnosis during endoscopy. With more advances in AI and larger studies to support its efficacy it would likely play a larger role in screening endoscopy in future.

Ceria Nanoparticles as Copper Chaperones that Activate SOD1 for Synergistic Antioxidant Therapy to Treat Ischemic Vascular Diseases.

All exogenous nanomaterials undergo rapid biotransformation once injected into the body and fall short of executing the intended purpose. Here, it is reported that copper-deposited ceria nanoparticles (CuCe NPs) exhibit enhanced antioxidant effects over pristine ceria nanoparticles, as the released copper buffers the depletion of glutathione while providing the bioavailable copper as a cofactor for the antioxidant enzyme, superoxide dismutase 1. The upregulated intracellular antioxidants along with the ceria nanoparticles synergistically scavenge reactive oxygen species and promote anti-inflammation and M2 polarization of macrophages by modulating signal transducer and activator of transcription 1 and 6 (STAT1 and STAT6). The therapeutic effect of CuCe NPs is demonstrated in ischemic vascular diseases (i.e., murine models of hindlimb ischemia and myocardial infarction) in which the copper-deposition affords increased perfusion and alleviation in tissue damage. The results provide rationale that metal oxide nanomaterials can be designed in a way to induce the upregulation of specific biological factors for optimal therapeutic performance.

Epitaxially Strained CeO2 /Mn3 O4 Nanocrystals as an Enhanced Antioxidant for Radioprotection.

Nanomaterials with antioxidant properties are promising for treating reactive oxygen species (ROS)-related diseases. However, maintaining efficacy at low doses to minimize toxicity is a critical for clinical applications. Tuning the surface strain of metallic nanoparticles can enhance catalytic reactivity, which has rarely been demonstrated in metal oxide nanomaterials. Here, it is shown that inducing surface strains of CeO2 /Mn3 O4 nanocrystals produces highly catalytic antioxidants that can protect tissue-resident stem cells from irradiation-induced ROS damage. Manganese ions deposited on the surface of cerium oxide (CeO2 ) nanocrystals form strained layers of manganese oxide (Mn3 O4 ) islands, increasing the number of oxygen vacancies. CeO2 /Mn3 O4 nanocrystals show better catalytic activity than CeO2 or Mn3 O4 alone and can protect the regenerative capabilities of intestinal stem cells in an organoid model after a lethal dose of irradiation. A small amount of the nanocrystals prevents acute radiation syndrome and increases the survival rate of mice treated with a lethal dose of total body irradiation.

Detection of Malingering Using Wechsler Adult Intelligence Scale-IV for Psychiatric Patients.

OBJECTIVE: Psychiatric patients sometimes show poor performance or exaggerated symptoms as malingering for secondary gain. The aim of this study was to introduce cut-off scores for detecting poor performance using Wechsler Adult Intelligence Scale (WAIS) in psychiatric patients. METHODS: Participants were 261 in- and out-patients who visited psychiatry department. They were classified into 4 group- 1) military service, 2) traumatic brain injury (TBI), 3) psychosis, 4) neurosis. A Digit Span subtest (called as Reliable Digit Span, RDS) of WAIS was used to detect malingering. This study considered a score of 10% base rate as RDS cut-off score. RESULTS: The RDS cut-off score was shown at 7 pts for military service group, at 3 pts for TBI group, at 6 pts for psychosis group, and at 6 pts for neurosis group. CONCLUSION: This study first introduced RDS cut-off scores for malingering psychiatric patients in South Korea. In clinical practice, clinicians may be able to utilize the RDS cut-off scores for malingering-suspected patients. In particular, for patients with military service issues, 7 or less pts of RDS can be used for detecting and inferring their malingering.

Cognitive Decline in Korean Patients with Neurocognitive Disorder due to Traumatic Brain Injury: A Control for Premorbid Intelligence.

OBJECTIVE: Previous studies of cognitive decline in patients with neurocognitive disorder due to traumatic brain injury (NCD-TBI) have often failed to control for baseline factors such as premorbid intelligence. The purpose of the current study was to estimate and compare cognitive function among three groups (controls, complicated mild/moderate TBI, and severe TBI) after controlling for premorbid intelligence. METHODS: Severity of TBI was classified as complicated mild/moderate or severe based on duration of loss of consciousness and brain neuroimaging results. Premorbid intelligence quotients (IQs) were estimated with the Oklahoma Premorbid Intelligence Estimate. There were no differences in premorbid intelligence between the groups, which were also matched for age and education. Current cognitive function was evaluated with the Wechsler Adult Intelligence Scale-Fourth Edition. RESULTS: Comparison of current cognitive function among the three groups indicated significant group differences for all indexes and subtest scores. Processing speed showed the highest effect size. However, only working memory differed significantly between the two NCD-TBI groups. CONCLUSION: The present findings suggest that mental memory manipulation processes seem to be more sensitive to TBI severity than are perceptual-motor processes. Specifically, both auditory rehearsal/discrimination and mental alertness/manipulation will be most strongly influenced by TBI severity.

Investigation on the Intrinsic Potential of Using Potassium Chloride for Partially Replacing NaCl in Kimchi and the Effect of Information on Consumer Acceptance of Sodium-Reduced Kimchi According to Age.

The high sodium content of kimchi is a contradicting factor from its fame as a healthy food. With the aim of reducing the sodium content of kimchi, the objective of this study was to understand the effect of providing "sodium-reduced" information on the acceptance of kimchi according to the age of consumption. Six sodium-reduced kimchi samples, prepared with different percentages of sodium reduction (25% and 50%) and potassium chloride concentration (none, 0.47%, and 0.93%), were compared to control kimchi (2.0% w/v NaCl). Sensory characterization of the samples was obtained using descriptive analysis. A total of 167 kimchi consumers with balanced proportion of the young (below 40) and the old (above 40) evaluated seven kimchi samples in either of the two conditions: blind testing condition or informed testing condition where each of the samples was provided with a label that informed about "sodium reduction percentage" and "whether a salt replacer was used or not." The results showed that in terms of healthiness perception, Korean female consumers believed that kimchi with a high sodium reduction rate would contribute to health in general, though an unfavorable notion of using a salt replacer was also observed. Also, the results suggested that promoting information about sodium reduction in kimchi would generally increase consumer acceptance. However, this phenomenon was influenced not only by the sample for which the information was provided, but also by the age of consumers with different health interests and kimchi experience. PRACTICAL APPLICATION: The findings of this study showed simply reducing sodium and promoting it with a health claim showed limitation in achieving a high level of sodium reduction, such as a 50% reduction rate, which implied the importance of using supplementary material such as potassium chloride that can fulfill the missing saltiness and flavors of the original product. Promotion of "sodium-reduced" claims in kimchi generally results in increased consumer acceptance. However, the effectiveness of the information was dependent on which sample was provided and the age of the consumers, among whom health interests and kimchi experience differ.

Large scale and integrated platform for digital mass culture of anchorage dependent cells.

Industrial applications of anchorage-dependent cells require large-scale cell culture with multifunctional monitoring of culture conditions and control of cell behaviour. Here, we introduce a large-scale, integrated, and smart cell-culture platform (LISCCP) that facilitates digital mass culture of anchorage-dependent cells. LISCCP is devised through large-scale integration of ultrathin sensors and stimulator arrays in multiple layers. LISCCP provides real-time, 3D, and multimodal monitoring and localized control of the cultured cells, which thereby allows minimizing operation labour and maximizing cell culture performance. Wireless integration of multiple LISCCPs across multiple incubators further amplifies the culture scale and enables digital monitoring and local control of numerous culture layers, making the large-scale culture more efficient. Thus, LISCCP can transform conventional labour-intensive and high-cost cell cultures into efficient digital mass cell cultures. This platform could be useful for industrial applications of cell cultures such as in vitro toxicity testing of drugs and cosmetics and clinical scale production of cells for cell therapy.

Highly selective microglial uptake of ceria-zirconia nanoparticles for enhanced analgesic treatment of neuropathic pain.

Neuropathic pain is a chronic and pathological pain caused by injury or dysfunction in the nervous system. Pro-inflammatory microglial activation with aberrant reactive oxygen species (ROS) generation in the spinal cord plays a critical role in the development of neuropathic pain. However, the efficacy of current therapeutic methods for neuropathic pain is limited because only neurons or neural circuits involved in pain transmission are targeted. Here, an effective strategy to treat pain hypersensitivity using microglia-targeting ceria-zirconia nanoparticles (CZ NPs) is reported. The CZ NPs are coated with microglia-specific antibodies to promote their delivery to microglia, and thus to improve their therapeutic efficacy. The targeted delivery facilitates the elimination of both pro-inflammatory cytokines and ROS in microglia, enabling the rapid and effective inhibition of microglial activation. As a result, greatly ameliorated mechanical allodynia is achieved in a spinal nerve transection (SNT)-induced neuropathic pain mouse model, proving the potent analgesic effect of the microglia-targeting CZ NPs. Given the generality of the approach used in this study, the microglia-targeting CZ NPs are expected to be useful for the treatment of not only neuropathic pain but also other neurological diseases associated with the vicious activation of microglia.

Sensory Properties and Consumer Acceptance of Cantaloupe Melon Cultivars.

This research measured the sensory characteristics and consumer acceptance of 15 cultivars of cantaloupe. Eleven trained panelists assessed melons by descriptive analysis. Northern California consumers (n = 171) evaluated the melons for overall, appearance, flavor, and texture liking on the 9-point hedonic scale and the adequacy of ripeness, sweetness, and firmness on a 5-point just-about-right (JAR) scale. Twenty-two sensory attributes differed significantly among the melons. CaldeoDF, Caldeo, Globstar, RML0499, and Caribbean Gold showed higher firmness, crunchiness, and denser textures. Impac presented higher watermelon flavor, bitterness, and sourness. Caldeo, CaldeoDF, Globstar, Magellan, and Sol Real had higher overall intensity, sweetness and oversweet flavor, longer-lasting aftertaste, and salivating mouthfeel. Consumers liked Magellan, Acclaim, and Primo most, and Aphrodite and Impac least, and the harvesting period was not critical to consumer acceptance. Sweet, oversweet flavor, and intense orange and richness of color were drivers of overall liking. Preference clustering identified three groups of consumers with distinct sensory preferences and favorite cultivars. JAR data showed Acclaim, Magellan, Primo, and Saguaro were just right for ripeness and so was Acclaim for firmness. All melons were judged not sweet enough. Growers and distributors could use the information from this research to improve the quality and appeal of the cantaloupe melon offering in the United States. PRACTICAL APPLICATION: We profiled the sensory attributes and measured consumer liking of 15 cantaloupe cultivars. Our findings should benefit producers and consumers equally as they identified those cultivars with the most promising sensory traits and they uncovered preference segments among a population of Northern California consumers as well as drivers of liking for those segments.

[Standardized access options for colorectal surgery with the da Vinci Xi system]. / Standardisierte Zugangsoptionen für die kolorektale Chirurgie mit dem Da-Vinci-Xi-System.

BACKGROUND: Performing colorectal surgery with previous da Vinci system generations presented some limitations that caused uncertainty for surgeons as they began to apply robotic technologies. The da Vinci Xi system is designed to overcome these limitations and to enable multiquadrant colorectal surgery. OBJECTIVE: The design concept of the da Vinci Xi system and the standardized access for colorectal surgery are explained. MATERIAL AND METHODS: The da Vinci Xi system applies an overhead boom that maximizes the arm workspace, minimizes interference and makes the port placement universal for standardized access. Colorectal approaches have been validated in numerous cadaver models confirming the reproducibility of the standardized access. RESULTS: Standardized access with a straight-line port placement is possible in all colorectal applications. For right-sided hemicolectomy, a transverse abdominal approach as well as a suprapubic port placement are possible. Utilizing the same principles, left-sided colectomy, sigmoid colectomy and low anterior resections can be performed. Proctocolectomy is enabled through boom rotation and a second docking. Only minor arm-to-arm interferences occurred and were easily manageable by the bedside assistant. None of the approaches required rearrangement of the patient cart or swapping arms to different port locations. CONCLUSION: The da Vinci Xi system enables a standardized access for colorectal surgery through a universal straight-line port placement. Learning this standard principle once enables the surgeon to apply it to all colorectal surgeries and shorten the learning curve as well as minimizing stress for both novices and experienced robotic surgeons learning a new surgical robotic platform.

Synergistic Oxygen Generation and Reactive Oxygen Species Scavenging by Manganese Ferrite/Ceria Co-decorated Nanoparticles for Rheumatoid Arthritis Treatment.

Poor O2 supply to the infiltrated immune cells in the joint synovium of rheumatoid arthritis (RA) up-regulates hypoxia-inducible factor (HIF-1α) expression and induces reactive oxygen species (ROS) generation, both of which exacerbate synovial inflammation. Synovial inflammation in RA can be resolved by eliminating pro-inflammatory M1 macrophages and inducing anti-inflammatory M2 macrophages. Because hypoxia and ROS in the RA synovium play a crucial role in the induction of M1 macrophages and reduction of M2 macrophages, herein, we develop manganese ferrite and ceria nanoparticle-anchored mesoporous silica nanoparticles (MFC-MSNs) that can synergistically scavenge ROS and produce O2 for reducing M1 macrophage levels and inducing M2 macrophages for RA treatment. MFC-MSNs exhibit a synergistic effect on O2 generation and ROS scavenging that is attributed to the complementary reaction of ceria nanoparticles (NPs) that can scavenge intermediate hydroxyl radicals generated by manganese ferrite NPs in the process of O2 generation during the Fenton reaction, leading to the efficient polarization of M1 to M2 macrophages both in vitro and in vivo. Intra-articular administration of MFC-MSNs to rat RA models alleviated hypoxia, inflammation, and pathological features in the joint. Furthermore, MSNs were used as a drug-delivery vehicle, releasing the anti-rheumatic drug methotrexate in a sustained manner to augment the therapeutic effect of MFC-MSNs. This study highlights the therapeutic potential of MFC-MSNs that simultaneously generate O2 and scavenge ROS, subsequently driving inflammatory macrophages to the anti-inflammatory subtype for RA treatment.

Screening for Lung Cancer Using Low-dose Chest Computed Tomography in Korean Long-term Colorectal Cancer Survivors

BACKGROUND: The National Lung Screening Trial (NLST) and NELSON trial showed that low-dose chest computed tomography (LDCT) screening significantly reduced the mortality form lung cancer. Although cancer survivors are known to have high risk for second malignant neoplasm (SMN), the usefulness of LDCT screening for lung cancer in cancer survivors is not clear. METHODS: Between August 2016 and August 2017, 633 long-term colorectal cancer (CRC) survivors visited the survivorship clinic in Cancer Prevention Center, Yonsei Cancer Center, Seoul, Republic of Korea. We surveyed the smoking status and recommended LDCT screening to ever-smoking CRC survivors aged 55–80 years. The participants were classified into three risk groups: risk group 1 (RG1) who met the NLST criteria (Age 55–74 years, ≥ 30 pack-years of smoking, smoking cessation < 15 years); risk group 2 (RG2) who would not meet the NLST criteria but were at increased 6-year risk of lung cancer (PLCOM2012 ≥ 0.0151); risk group 3 (RG3) who did not meet any of the criteria above. RESULTS: Among 176 ever-smoking CRC survivors, 173 (98.3%) were male, 32 (18.2%) were current-smoker, and median age was 66 years (range, 55–79 years). We found 38 positive findings (non-calcified nodule ≥ 4 mm), 8 clinically significant findings, 66 minor abnormalities, and 64 negative findings on LDCT. Positive findings were identified in 15 of 79 (19.0%) of RG1, in 9 of 36 (25%) of RG2, and in 14 of 61 (23.0%) of RG3. Second primary lung cancers were found in 2 patients of RG2, and in 1 patient of RG3. SMN was most frequently found in RG2 (11 of 36 patients, 30.6%), compared with RG1 (12.7%) or RG3 (9.8%) (P = 0.016). CONCLUSIONS: LDCT screening for lung cancer in Korean CRC survivors is feasible. Well-designed clinical trial for defining high risk patients for lung cancer among CRC survivors is needed.

Impact of tumor sidedness on survival and recurrence patterns in colon cancer patients

PURPOSE: Previous studies have reported conflicting results regarding the prognostic value of tumor sidedness in colon cancer. We investigated the oncologic impact of tumor location and examined whether recurrence patterns were related to tumor sidedness in colon cancer patients. METHODS: We identified stage I–III colon adenocarcinoma patients from a prospective colorectal cancer registry at Severance Hospital, Seoul, Korea, who underwent complete mesocolic excision between 2005 and 2012. Adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for predictors of cancer-specific survival (CSS), recurrence-free survival (RFS), and cumulative recurrence at specific anatomic sites were examined using Cox proportional hazard regression analysis. RESULTS: Overall, 1,912 patients, 1,077 (56.3%) with left-sided colon cancer (LCC), and 835 (43.7%) with right-sided colon cancer (RCC), at a median follow-up of 59 months, were eligible and included in the study. In univariate analysis, similar 5-year CSS and RFS were observed for LCC and RCC in the total patient population, and when stratified by stage for stage I and II patients. For stage III patients, an adjusted Cox regression analysis indicated that RCC patients had a higher risk of cancer-specific mortality (HR, 1.75; 95% CI, 1.07–2.86; P = 0.024) and recurrence (HR, 1.78; 95% CI, 1.22–2.60; P = 0.003). Furthermore, RCC was an independent predictor of peritoneal recurrence (HR, 1.86; 95% CI, 1.05–3.29; P = 0.031) in stage III patients. CONCLUSION: RCC correlated with worse CSS and RFS than LCC. In stage III patients, RCC correlated with increased risk of peritoneal recurrence. The reasons for these differences remain to be investigated.

Short-term Outcomes After Upfront Chemotherapy Followed by Curative Surgery in Metastatic Colon Cancer: A Comparison With Upfront Surgery Patients

PURPOSE: Upfront systemic chemotherapy with target agents has been recommended for patients with stage IV colon cancer. Some with partial response are considered for curative resection. There is high risk of developing postoperative complications following upfront systemic chemotherapy. We aimed to evaluate short-term perioperative outcomes of curative surgery after upfront chemotherapy in comparison with upfront surgery in patients with metastatic colon cancer.METHODS: Between January 2010 and October 2015, 146 patients (80 in the surgery first group, 66 in the upfront chemotherapy group) who underwent surgical resection before or after systemic chemotherapy for metastatic colon cancer were included in the present study. All decisions for treatment were made through a multidisciplinary team. Postoperative clinical outcomes and complications were analyzed to compare the groups.RESULTS: There was no difference between the 2 groups in terms of postoperative clinical outcomes. Overall complication rates were not different between the groups (surgery first group: 46.3% vs. upfront chemotherapy group: 60.6%; P = 0.084). When classified according to the Clavien-Dindo method, there was no difference between the 2 groups in terms of major complications (grade 3 or more) (surgery first group: 18.9% vs. upfront chemotherapy group: 27.5%; P = 0.374).CONCLUSION: There was no significant increase in major postoperative complications in metastatic colon cancer patients who received upfront chemotherapy followed by curative surgery. Careful patient selection and treatment planning are important.

Impact of Adjuvant Chemotherapy Completion on Oncologic Outcomes in ypTNMstage 2 Rectal Cancer Patients

PURPOSE: Adjuvant chemotherapy (aCT) in rectal cancer patients who have undergone curative resection after neoadjuvant chemoradiation (nCRT) is controversial. We aimed to investigate the benefits of using aCT and the clinical impact of completing aCT in ypstage 2 rectal cancer patients.METHODS: We retrospectively reviewed clinicopathological data from patients who had undergone radical resection after nCRT between January 2006 and December 2012. In total, 152 patients with ypT3/4N0M0 rectal cancer were included. Of these patients, 139 initiated aCT, while 13 did not receive aCT (no-aCT). Among those who received aCT, 132 patients completed their planned cycles (aCT-completion) whereas 7 did not (aCT-incompletion). All patients received longcourse chemoradiation; a 5-fluorouracil-based regimen was used for nCRT in most patients. The prognostic factors affecting disease-free survival (DFS) and overall survival (OS) were analyzed.RESULTS: The median follow-up duration was 41 months. Demographic data did not differ significantly among the 3 groups. In multivariate analysis, open surgery, a tumor size >2 cm, retrieval of <12 lymph nodes, circumferential resection margin (CRM) positivity and aCT incompletion were independent prognostic factors for poor DFS. Old age (≥60 years), open surgery, CRM positivity, aCT incompletion, and lack of aCT initiation compared to aCT completion were independent prognostic factors for poor OS.CONCLUSION: In ypstage 2 rectal cancer patients, aCT after nCRT and total mesorectal excision affected both DFS and OS; however, only patients who completed planned aCT exhibited survival benefits. Therefore, improving patients’ compliance with the completion of aCT is desirable.

Single-center Experience of 24 Cases of Tailgut Cyst

PURPOSE: Tailgut cysts are rare congenital or developmental lesions that arise from vestiges of the embryological hindgut. They are usually present in the presacral space. We report our single-center experience with managing tailgut cysts. METHODS: We conducted a retrospective analysis of 24 patients with tailgut cyst treated surgically at the Colorectal Surgery Department of Severance Hospital, Yonsei University, Seoul, South Korea, between 2007–2018. RESULTS: This study included 24 patients (18 females) with a median age of 51.5 years (range, 21–68 years). Ten cases were symptomatic and 14 were asymptomatic. Cysts were retrorectal in 21 patients. Cysts were below the coccyx level in 16 patients, opposite the coccyx in 6, and above the coccyx in 2. Cysts were supralevator in 5 patients, had a supra- and infralevator extension in 18 patients, and were infralevator in 1. Ten patients were managed using an anterior laparoscopic approach, 11 using a posterior approach, and 3 using a combined approach. Mean cyst size was 5.5 ± 2.7 cm. Postoperative complications were Clavien-Dindo (CD) classification grade II in 9 patients (37.5%) and CD grade III in 1 (4.2%). The posterior approach group showed the highest rate of complications (P = 0.021). Patients managed using a combined approach showed a larger cyst size (P < 0.001), longer operation times (P < 0.001), and a greater likelihood of tumor level above the coccyx (P = 0.002) compared to other approaches. The tumors of 2 male patients were malignant: 1 was a neuroendocrine tumor treated with radiotherapy, while the other was a closely followed adenocarcinoma. Median follow-up was 12 months (range, 1–66 months) with no recurrence. CONCLUSION: Tailgut cysts are uncommon but can cause perineal or pelvic pain. Complete surgical excision via an appropriate approach according to tumor size, location, and correlation with adjacent pelvic floor muscles is the key treatment.

Gender differences in bronchiectasis: a real issue?

Gender differences in chronic respiratory disease, including cystic fibrosis and non-cystic fibrosis bronchiectasis are clinically apparent and of increasing importance. Differences in disease prevalence, severity and outcome are all described, however, the precise cause of the gender dichotomy and their associated underlying mechanisms have been poorly characterised. A lack of dedicated clinical and epidemiological research focused in this area has led to a paucity of data and therefore a lack of understanding of its key drivers. Diagnosis, disease pathogenesis and treatment response are all complex but important aspects of bronchiectasis with an evident gender bias. Broadening our understanding of the interplay between microbiology, host physiology and the environment in the context of chronic lung diseases, such as bronchiectasis, is critical to unravelling mechanisms driving the observed gender differences. In this review, epidemiological, biological and environmental evidence related to gender in bronchiectasis is summarised. This illustrates gender differences as a "real issue" with the objective of mapping out a future framework upon which a gender-tailored medical approach may be incorporated into the diagnosis, monitoring and treatment of bronchiectasis. KEY POINTS: CF and non-CF bronchiectasis are complex, multifactorial chronic pulmonary diseases with gender-specific differences in their prevalence, clinical presentation and disease severity.Microbiology and host physiology (immune and inflammatory responses) are essential aspects of bronchiectasis that are influenced by gender.Sex steroid hormones vary in type, fluctuating pattern and concentration throughout life and between the genders with a potential central role in bronchiectasis-related gender differences.Gender-focused clinical and/or therapeutic intervention has the potential to narrow the observed gender gap occurring in bronchiectasis-related lung disease. EDUCATIONAL AIMS: To summarise the existing knowledge base of gender-related differences in CF and non-CF bronchiectasis.To highlight key areas of importance in the diagnosis, monitoring and treatment of bronchiectasis that is amenable to clinical and/or pharmacological intervention to narrow the existing "gender gap".