Effects of prior endoscopic resection on recurrence in patients with T1 colorectal cancer who underwent radical surgery.

PURPOSE: Endoscopic resection (ER) is a reliable treatment for early colorectal cancer without lymph node metastasis. We aimed to examine the effects of ER performed prior to T1 colorectal cancer (T1 CRC) surgery by comparing long-term survival after radical surgery with prior ER to that after radical surgery alone. METHODS: This retrospective study included patients who underwent surgical resection of T1 CRC at the National Cancer Center, Korea, between 2003 and 2017. All eligible patients (n = 543) were divided into primary and secondary surgery groups. To ensure similar characteristics between the groups, 1:1 propensity score matching was used. Baseline characteristics, gross and histological features, along with postoperative recurrence-free survival (RFS) between the two groups were compared. Cox proportional hazard model was used to identify the risk factors affecting recurrence after surgery. Cost analysis was performed to examine the cost-effectiveness of ER and radical surgeries. RESULTS: No significant differences were observed in 5-year RFS between the two groups in matched data (96.9% vs. 95.5%, p = 0.596) and in the unadjusted model (97.2% vs. 96.8%, p = 0.930). This difference was also similar in subgroup analyses based on node status and high-risk histologic features. ER before surgery did not increase the medical costs of radical surgery. CONCLUSION: ER prior to radical surgery did not affect the long-term oncologic outcomes of T1 CRC or significantly increased the medical costs. Attempting ER first for suspected T1 CRC would be a good strategy to avoid unnecessary surgery without concerns of worsening cancer-related prognosis.

Safety of early surgery after self-expandable metallic stenting for obstructive left-sided colorectal cancer.

BACKGROUND: Self-expanding metallic stenting (SEMS) is usual for the temporary resolution of obstructive left-sided colorectal cancer (CRC) as a bridge to elective surgery. However, there is no consensus regarding adequate time intervals from stenting to radical surgery. The aim of this study was to identify the optimal time interval that results in favorable short- and long-term outcomes. METHODS: Data on patients with obstructive left-sided CRC who underwent elective radical surgery after clinically successful SEMS deployment in five tertiary referral hospitals from 2004 to 2016 were analyzed, retrospectively. An inverse probability treatment-weighted propensity score analysis was used to minimize bias. Postoperative short- and long-term outcomes were compared between two groups: an early surgery (within 8 days) group and delayed surgery (after 8 days) group. RESULTS: Of 311 patients, 148 (47.6%) underwent early and 163 (52.4%) underwent delayed surgery. The median surgery interval was 9.0 days. After adjustment, the groups had similar patient and tumor characteristics. In terms of short-term outcomes, there was no difference in hospitalization length or postoperative complications. No deaths were observed. With a median follow-up of 71.0 months, no significant difference was observed between the groups in 5-year overall survival (early vs. delayed surgery: 79.6% vs. 71.3%, P = 0.370) and 5-year disease-free survival (early vs. delayed surgery: 59.1% vs. 60.4%, P = 0.970). CONCLUSIONS: In obstructive left-sided CRC, the time interval between SEMS and radical surgery did not significantly influence short- and long-term outcomes. Therefore, early surgery after SEMS could be suggested if there is no reason to postpone surgery for preoperative medical optimization.

Molecular, biochemical, and toxicological characterization of two acetylcholinesterases from the Western flower thrips, Frankliniella occidentalis.

We investigated the molecular and biochemical properties of two acetylcholinesterases (FoAChE1 and FoAChE2) from the Western flower thrips, Frankliniella occidentalis. Polyacrylamide gel electrophoresis and western blotting confirmed the membrane-anchored nature of both FoAChE1 and FoAChE2, which was further supported by hydrophobicity and glycophosphatidylinositol anchor predictions. High expression levels of both enzymes were observed in the head, indicating their predominant distribution in neuronal tissues. FoAChE1 exhibited significantly higher expression levels in all examined tissues compared to FoAChE2, suggesting its major role as a synaptic enzyme. Nonetheless, both recombinant enzymes displayed robust catalytic activity toward acetylthiocholine iodide, and FoAChE1 demonstrated nearly identical catalytic efficiency compared to FoAChE2. FoAChE1 exhibited slightly lower sensitivities to the cholinesterase inhibitors tested, including organophosphates (OPs) and carbamates (CBs), compared to FoAChE2. Field populations of F. occidentalis exhibited polymorphism of alanine vs. serine at position 197 of FoAChE1 within the conserved oxyanion hole. Contrary to common belief, however, functional analysis using recombinant enzymes revealed that neither A197 nor S197 residue was associated with FoAChE1 insensitivity to OPs and CBs. FoAChE2 did not exhibit any polymorphic amino acid substitutions at the positions known to be associated with resistance. Due to the absence of apparent resistance-associated mutations in field populations of F. occidentalis, the judicious use of some OPs or CBs can be suggested for controlling the highly resistant populations to other insecticides. Overall, our findings highlight the significance of both FoAChE1 and FoAChE2 as targets for toxicity assessment, while the specific contribution of each enzyme to toxicity remains unclear.

First report of anthracnose on spotted laurel caused by Colletotrichum fructicola in South Korea.

Spotted laurel (Aucuba japonica) is a popular ornamental bush (it has two-colored leaves and red berries) and is used outdoors and indoors for decoration in South Korea. Anthracnose reduces the aesthetic value of spotted laurel leaves. In August 2022, anthracnose symptoms were observed on leaves in a park at Jeju Island, South Korea. Approximately 55% of bushes were infected by this disease. Symptoms consisted of round or irregular lesions that initially appeared as black spots and coalesced into larger, black lesions covering whole leaves and twigs. Entire leaves wither and finally die. To identify the putative causal agent, 12 affected leaves were collected, placed in a plastic box containing moist tissue, and incubated at 25 ºC in the dark to obtain conidial mass. Conidial masses were produced on leaf lesions after 2 days, and then 12 morphologically similar fungal isolates were recovered following single the spore isolation technique on solid potato dextrose agar (PDA) (Cai et al. 2009). Ten-day-old colonies were olivaceous gray with immersed perithecia on the upper side and black at the center on the reverse side. Conidia were aseptate, cylindrical with round ends and measured 14.9 - 22.7 × 5.5 - 9.4 µm (n = 80). Appressoria were brown, irregular in shape, and 7.0 - 16.1 × 5.00 - 9.9 µm (n = 50). Asci were eight-spored, banana-shaped, and measuring 60.8 - 123.1 × 13.00 - 18.9 µm (n = 30). Hyaline ascospores were single-celled, curved or straight with round ends, and ranged in size was 15.5 - 23.3 × 5.1 - 11.8 µm (n = 50). The morphological characteristics of the isolates overlapped with those of Colletotrichum species within the C. gloeosporioides complex, including Colletotrichum fructicola (Weir et al. 2012). Five genomic DNA loci of the isolates, including the partial ITS rDNA region, ACT, GAPDH, TUB, and ApMat genes, were amplified and sequenced using ITSF1/ITS4, ACT-512F/ACT-783R, GDF/GDR, T1/Bt2b, and AM-F/AM-R, respectively (Silva et al. 2012; Weir et al. 2012). The resulting consensus sequences were deposited in the GenBank and the accession numbers (ITS = LC739331- LC739334, TUB = LC739335- LC739338, GAPDH = LC739339- LC739342, ACT = LC739343 -LC739346, ApMat = LC742925 - LC742928) were obtained. A maximum phylogenetic tree was constructed based on the combined data sets of ITS, ACT, GAPDH, TUB, ApMat sequences. The isolates were clustered with reference isolates of C. fructicola (isolates ICMP18581). The pathogenicity test was performed on uninfected, healthy spotted laurel cuttings in the pot. Five leaves per seedling were selected, surface sterilized with 70% ethanol, and rinsed with sterile distilled water (SDW). A sterile pin was used to make 3 to 4 wounds on each side of the leaf from the midrib. 10 µl of spore suspension per wound spot (1 × 106 spores/ml) was applied on the wounds of one site from midrib, and SDW was placed on the wounds of other site as a control. The treated seedlings were covered with sterile plastic bag and kept in a 12-h fluorescent light/dark cycle under greenhouse conditions at 25 ± 2°C and 80% relative humidity. Two seedlings were inoculated with a single isolate, and this experiment was repeated twice. Circular or irregular lesions appeared after 5 days of inoculation, while the control remained asymptotic. Koch's postulates were fulfilled by reisolating and reidentifying the causal agent from the lesions of inoculated leaves. Colletotrichum fructicola has been reported as the causal agent of anthracnose on mango (Joa et al. 2016), apple (Kim et al. 2018), grapes (Lim et al. 2019), peaches (Lee et al. 2020), and hybrid pear (Choi et al. 2021) in South Korea. To the best of our knowledge, it is the first report of C. fructicola causing anthracnose on spotted laurel. This study will be helpful to develop effective management strategies to minimize leaf lesions.

Morphological and Molecular Characterization of Diplogasteroides sp., a Cryptic Population of the Haslacheri Group (Diplogastridae), and Parasitorhabditis terebranus (Rhabditidae) from Korea.

Diplogasteroides sp., a cryptic population of D. haslacheri, and Parasitorhabditis terebranus were reported from the frass of Monochamus alternatus galleries in dead Pinus thunbergii for the first time in Korea. Females and males are morphologically characterized and their linked DNA barcodes (18S-rRNA, 28S-rRNA, ITS-rRNA and COI) supplied. Females and males of the two species from Korea conform to the original species descriptions from Europe and the USA, with variations in a few details in morphometrics. Specifically, Diplogasteroides sp. is morphologically very similar to D. haslacheri. However, it cannot be designated as D. haslacheri due to the existence of cryptic species complex within the haslacheri group (D. haslacheri, D. asiaticus, D. nix, D. andrassyi, and D. carinthiacus), a condition requiring hybridization studies to test species identity within the group. Based on analysis of COI sequences, differences among these cryptic species are evident. Thus, in addition to hybridization tests, the COI might be a powerful DNA barcoding marker for the precise identification of these cryptic species within the genus. Additionally, this is the first molecular characterization of P. terebranus, and the species is herein recorded for the first time outside its type locality.

Comparison of tumor regression grade and clinical stage based on MRI image as a selection criterion for non-radical management after concurrent chemoradiotherapy in locally advanced rectal cancer: a multicenter, retrospective, cross-sectional study.

PURPOSE: There has been no comparative study on the clinical value of magnetic resonance tumor regression grade (mrTRG)1-2 and ycT0-1N0 for the prediction of ypT0-1N0 after concurrent chemoradiotherapy (CCRT) for rectal cancer. We compared the diagnostic performance between mrTRG1-2 and ycT0-1N0 for predicting ypT0-1N0 as a selection criterion for non-radical management after CCRT in locally advanced rectal cancer. METHODS: This retrospective study enrolled 291 patients from three referral hospitals between January 2018 and March 2020. The diagnostic performance of ycT0-1N0 and mrTRG1-2 for the prediction of ypT0-1N0 was compared in terms of sensitivity, specificity, positive-predictive value, negative-predictive value, and area under the curve (AUC). RESULTS: Sixty-eight patients (23.4%) achieved ypT0-1N0. Nineteen patients (6.5%) had ycT0-1N0, and 91 patients (31.2%) had mrTRG1-2. For predicting ypT0-1N0, ycT0-1N0 had a sensitivity of 16.2% (95% confidence interval [CI]: 8.36‒27.10) and positive-predictive value of 57.9% (95% CI: 36.57‒76.63), while mrTRG1-2 had a sensitivity of 58.8% (95% CI: 46.23‒70.63) and positive-predictive value of 44.0% (95% CI: 36.46‒51.74). When predicting ypT0-1N0, mrTRG1-2 showed a higher AUC (0.680, 95% CI: 0.604‒0.756) than ycT0-1N0 (0.563, 95% CI: 0.481‒0.645) (P < 0.001). CONCLUSION: mrTRG1-2 might be a better indicator than ycT0-1N0 for the selection of non-radical management of advanced rectal cancer post-CCRT. However, additional diagnostic tools are required for predicting ypT0-1N0 because mrTRG1-2 or yc stage on MRI has insufficient evidence for diagnosing ypT0-1N0.

Factors associated with diet failure after colon cancer surgery.

BACKGROUND: Since the introduction of Enhanced Recovery After Surgery (ERAS), early diet after surgery has been emphasized and clinical outcomes have improved, though vomiting has been reported frequently. We defined diet failure based on clinical manifestation and images after colon cancer surgery and attempted to analyze underlying risk factors by comparing the early diet group with the conventional diet group. METHODS: All consecutive patients underwent colectomy with curative intent at a single institution between August 2015 and July 2017. The early diet group was started on soft diet on the second day after surgery, while the conventional group started the same after flatulence. The primary outcome was the difference in the incidence of diet failure between the two groups. Secondary outcomes were analyzed to determine risk factors for diet failure and readmission due to ileus. RESULTS: Overall, 293 patients were included in the conventional diet group and 231 in the early diet group. There were no significant differences between the two groups, except for shorter hospital stays in the early diet group (median 8 days, p < 0.001). A total of 46 patients (early diet, n = 20; conventional diet, n = 26, p = 1.000) had diet failure. Multivariate analysis showed that operation time (odds ratio [OR] 1.76, 95% confidence interval [CI] 1.33-2.32) and side-to-side anastomosis compared with the end-to-end method (OR 4.41, 95% CI 2.10-9.24) were independent risk factors for diet failure. Sixteen patients were readmitted due to ileus that occurred within 2 months after surgical operation. Diet resumption time was not a risk factor for both diet failure and ileus. CONCLUSIONS: Early diet resumption does not increase diet failure and can reduce hospital stay. Anastomosis and operation time may be related to diet failure. Our study suggests that evaluation of surgical factors is important for postoperative recovery, and well-designed follow-up studies are needed.

Analysis of metachronous colorectal neoplasms and survival following segmental or extended resection in patients with hereditary non-polyposis colorectal cancer.

PURPOSE: The high incidence of metachronous colorectal tumours in patients with hereditary non-polyposis colorectal cancer (HNPCC) encourages extended resection (ER); however, the optimal surgical approach remains unclear. We evaluated the incidences of metachronous colorectal neoplasms following curative colorectal cancer segmental resection (SR) vs ER in patients with HNPCC and investigated patients' oncologic outcomes according to surgical modality and mismatch repair status. METHODS: We retrospectively investigated medical records of patients with HNPCC (per the Amsterdam II criteria) treated for primary colon cancer at our institution between 2001 and 2017. All patients underwent intensive endoscopic surveillance. RESULTS: We included 87 patients (36 who underwent SR and 51 who underwent ER). The cumulative incidence of metachronous adenoma was higher in the SR group. One patient in the SR group (2.8%) and 3 in the ER group (5.9%) developed metachronous colon cancer; the difference was not significant (P = 0.693). Four patients in the SR group (11.1%) and 1 in the ER group (2.0%) developed distant recurrences; again, the difference was not significant (P = 0.155). Moreover, no significant differences were observed in the 5-year overall survival rates of patients in the SR and ER groups (88.2% vs 95.5%, P = 0.446); the same was true for 5-year disease-free survival rates (79.5% vs 91.0%, P = 0.147). CONCLUSION: The incidence of metachronous cancer was not significantly different between the ER and SR groups; however, that of cumulative metachronous adenoma was higher in the SR group. Hence, intensive surveillance colonoscopy may be sufficient for patients with HNPCC after non-extensive colon resection.

Implant fracture failure rate and potential associated risk indicators: An up to 12-year retrospective study of implants in 5,124 patients.

OBJECTIVES: This study investigated fracture rates and risk indicators for fractures in internal connection dental implants. MATERIAL AND METHODS: We performed a retrospective analysis of 19,006 internal connection implants used in fixed restoration in 5,124 patients (4,570 males, 554 females) at the Dental Hospital of Veterans Health Service Medical Center between 2006 and 2015. Patients were followed through June 2018 (0.03-12.39 years post-installation). Clinical factors (age, sex, implant diameter, implant length, placement site, bone graft, fixture material, cervical feature, abutment connection, microthread, and platform switching) were recorded. Kaplan-Meier survival analysis identified risk indicators associated with an implant fracture. Cox regression models elucidated potential fracture risks. RESULTS: One hundred and seventy-four implants fractured in 135 patients, for an incidence rate of 0.92% after an average of 4.95 ± 2.14 years of use. Kaplan-Meier estimates showed that the 3-, 5-, and 10-year survival rates of implants were 99.8%, 99.2%, and 97.7%, respectively. In the multivariable Cox regression model, the diameter, location, history of bone graft, and microthread presence were significantly correlated with implant fractures. Wide-diameter implants had a reduced fracture risk within 90 months, after which the diameter did not correlate with fractures. Implants placed in the anterior mandible had a lower fracture risk within 90 months; mandibular premolar implants corresponded with a lower risk after 90 months. Implants without a history of bone graft or microthreads were more likely to fracture throughout the follow-up time. CONCLUSIONS: These results elucidate risk indicators for implant fractures and facilitate their reduction in clinical practice.

A retrospective comparison of three modalities for vestibuloplasty in the posterior mandible: apically positioned flap only vs. free gingival graft vs. collagen matrix.

OBJECTIVES: This work aimed to comparatively evaluate the three modalities of vestibuloplasty around implants in the posterior mandible. MATERIALS AND METHODS: Forty patients who presented with a shallow vestibule and insufficient keratinized gingiva were divided into three groups: apically positioned flap only (APF group), APF with free gingival graft (FGG group), and APF with collagen matrix (CM group). The width of KT was measured at baseline, immediately after surgery (T0), and 6 months (T6) and 12 months after surgery (T12). An esthetic evaluation (color match, contour, and texture) was conducted. RESULTS: Most of the shrinkage occurred within 6 months. The FGG group demonstrated less shrinkage of KT up to 12 months compared to the APF and CM groups. The APF and CM groups exhibited a prolonged and similar rate of shrinkage. The APF and CM groups also showed significantly better esthetic profiles. CONCLUSIONS: Within the limitations of the present study, FGG may be the most predictable modality for increasing KT in the posterior mandible, but it should be emphasized that the posterior mandible does not require high esthetics. CLINICAL RELEVANCE: The effect of apically positioned flap and collagen matrix may be diminished by several factors in posterior mandible, such as low vestibule and high muscle pull. For increasing the dimension of keratinized tissue in posterior mandible, conventional free gingival graft may be more predictable compared to other options.

Retrospective Analysis of Sinus Membrane Thickening: Profile, Causal Factors, and Its Influence on Complications.

PURPOSE: To retrospectively determine the profile of the sinus membrane (SM), potential factors affecting SM thickening (SMT), and the correlation between SMT and sinus augmentation (SA) complications. MATERIALS AND METHODS: In the patients who received lateral SA, SMT was classified in sagittal sections of cone-beam computed tomography according to its thickness and morphology. The correlation between SMT and the following factors was analyzed: age, sex, endodontic and periodontic statuses of neighboring teeth, and shape of the sinus inferior border. The association between SMT and SA complications was investigated. RESULTS: SMT of ≤2 mm was prevalent (60%). Irregular SM was mostly observed for SMT of >2 mm. There was no statistically significant association between SMT and the included factors. SMT did not significantly correlate with either perforation or postoperative complications. There was a statistically significant increase in implant failure when SMT was >2 mm, but it was hard to determine that the failure was solely affected by SMT. CONCLUSION: SMT was not influenced by the factors included in this study, and it might not be a risk factor for SA and implant failure.

Simultaneous Block Bone Grafting Using "L-Shaped Notch" Preparation in Mandible: Case Series and 1-Year Follow-up.

PURPOSE: A novel autogenous block bone grafting technique with simultaneous placement of dental implants is described for several cases of horizontal ridge augmentation. METHODS: Seven patients with a mandibular horizontal ridge that was inadequate for proper implant placement were included in this study. Simultaneous implant placement and autogenous block bone grafting was planned; we designed the "L-shaped notch" preparation of the recipient site for the additional fixation with only 1 screw. This new technique also required minimal size of autogenous block bone. RESULTS: In total, 11 implants and final restorations were delivered in 7 patients. The dehiscence defects were covered successfully (79.70 ± 5.58%; 2.26 ± 0.68 mm) at the uncover surgery. The marginal bone loss was 0.50 ± 0.26 mm on the mesial side and 0.58 ± 0.23 mm on the distal side. The outcomes were satisfactory clinically and radiographically during the 1-year follow-up. CONCLUSION: Although additional studies, with more than 7 patients, are needed to evaluate the L-shaped notch preparation, this was effective to accomplish horizontal ridge augmentation simultaneously with the placement of dental implants using the minimal size of autogenous block bone.

Vertical Ridge Augmentation with Customized Titanium Mesh Using a 3D-Printing Model: A Prospective Study in Humans.

PURPOSE: To evaluate the usefulness of ridge augmentation using a customized titanium mesh (CTM) that was preformed by trimming and bending the commercial titanium mesh on a virtually reconstructed 3D acrylic resin model using clinical, radiologic, histologic, and histomorphometric analyses. MATERIALS AND METHODS: This study was designed prospectively for patients who required vertical ridge augmentation using a staged approach before implant surgery. After installation of the CTM, grafting was performed using deproteinized porcine bone mineral covered with an absorbable membrane. Computed tomography was performed preoperatively and 6 months after simultaneous/staged guided bone regeneration to measure planned, reconstructed, and lacking bone volume, and the reconstruction rate was calculated based on these values. Clinical complications were also recorded, particularly the mesh exposure rate. At re-entry, the bone core was obtained using a trephine bur, and histologic and histomorphometric analyses were performed. RESULTS: A total of 10 sites in eight patients were used for the study analysis. The mean planned bone volume was 1.15 cm3 (range: 0.78 to 1.56 cm3), mean lacking bone volume was 0.13 cm3 (range: 0 to 0.59 cm3), and mean reconstructed bone volume was 1.02 cm3 (range: 0.56 to 1.43 cm3). The exposure rate was 30% (3 out of 10 sites). The reconstruction rate was over 80%, except for one case that showed suppuration. From histomorphometric analysis, 27.52% ± 16.87% of new bone, 7.62% ± 5.19% of residual graft, and 64.86% ± 23.76% of connective tissue were observed. The core biopsy samples demonstrated different pseudoperiosteum layer appearances based on the healing stage of the augmented sites. In the premature bone, the inner osteogenic layer consisted of multiple layers of osteoblast cells with adjacent large blood vessels. However, in the mature augmented site, there was no specific inner osteogenic layer, and the outer fibrous layer was dominant. CONCLUSIONS: The fabrication of CTM based on the application of the 3D-printing technique makes vertical ridge augmentation easier and can reduce complications and achieve target bone acquisition. In addition, it is expected that quantitative analysis of the pseudoperiosteum layer will be facilitated using the CTM.

A Revision of the Phylogeny of Helicotylenchus Steiner, 1945 (Tylenchida: Hoplolaimidae) as Inferred from Ribosomal and Mitochondrial DNA.

Identification of Helicotylenchus species is very challenging due to phenotypic plasticity and existence of cryptic species complexes. Recently, the use of rDNA barcodes has proven to be useful for identification of Helicotylenchus. Molecular markers are a quick diagnostic tool and are crucial for discriminating related species and resolving cryptic species complexes within this speciose genus. However, DNA barcoding is not an error-free approach. The public databases appear to be marred by incorrect sequences, arising from sequencing errors, mislabeling, and misidentifications. Herein, we provide a comprehensive analysis of the newly obtained, and published DNA sequences of Helicotylenchus, revealing the potential faults in the available DNA barcodes. A total of 97 sequences (25 nearly full-length 18S-rRNA, 12 partial 28S-rRNA, 16 partial internal transcribed spacer [ITS]-rRNA, and 44 partial cytochrome c oxidase subunit I [COI] gene sequences) were newly obtained in the present study. Phylogenetic relationships between species are given as inferred from the analyses of 103 sequences of 18S-rRNA, 469 sequences of 28S-rRNA, 183 sequences of ITS-rRNA, and 63 sequences of COI. Remarks on suggested corrections of published accessions in GenBank database are given. Additionally, COI gene sequences of H. dihystera, H. asiaticus and the contentious H. microlobus are provided herein for the first time. Similar to rDNA gene analyses, the COI sequences support the genetic distinctness and validity of H. microlobus. DNA barcodes from type material are needed for resolving the taxonomic status of the unresolved taxonomic groups within the genus.

Treatment for appendicitis in cancer patients on chemotherapy: a retrospective cohort study.

Purpose: Whether to perform surgery or conservatively manage appendicitis in immunosuppressed patients is a concern for clinicians. This study aimed to compare the outcomes of these 2 treatment options for appendicitis in patients with cancer undergoing chemotherapy. Methods: This retrospective study included 206 patients with cancer who were diagnosed with acute appendicitis between August 2001 and December 2021. Among them, patients who received chemotherapy within 1 month were divided into surgical and conservative groups. We evaluated the outcomes, including treatment success within 1 year, 1-year recurrence, and the number of days from the diagnosis of appendicitis to chemotherapy restart, between the 2 groups. Results: Among the 206 patients with cancer who were diagnosed with acute appendicitis, 78 received chemotherapy within 1 month. The patients were divided into surgery (n = 63) and conservative (n = 15) groups. In the surgery group, the duration of antibiotic therapy (7.0 days vs. 16.0 days, P < 0.001) and length of hospital stay (8.0 days vs. 27.5 days, P = 0.002) were significantly shorter than conservative groups. The duration from the diagnosis of appendicitis to the restart of chemotherapy was shorter in the surgery group (20.8 ± 15.1 days vs. 35.2 ± 28.2 days, P = 0.028). The treatment success rate within 1 year was higher in the surgery group (100% vs. 33.3%, P < 0.001). Conclusion: Surgical treatment showed a significantly higher success rate than conservative treatment for appendicitis in patients less than 1 month after chemotherapy. Further prospective studies will be needed to clinically determine treatment options.

Long-term clinical outcomes after high and low ligations with lymph node dissection around the root of the inferior mesenteric artery in patients with rectal cancer.

PURPOSE: This study aimed to evaluate the long-term clinical outcomes based on the ligation level of the inferior mesenteric artery (IMA) in patients with rectal cancer. METHODS: This was a retrospective analysis of a prospectively collected database that included all patients who underwent elective low anterior resection for rectal cancer between January 2013 and December 2019. The clinical outcomes included oncological outcomes, postoperative complications, and functional outcomes. The oncological outcomes included overall survival (OS) and relapse-free survival (RFS). The functional outcomes, including defecatory and urogenital functions, were analyzed using the Fecal Incontinence Severity Index, International Prostate Symptom Score, and International Index of Erectile Function questionnaires. RESULTS: In total, 545 patients were included in the analysis. Of these, 244 patients underwent high ligation (HL), whereas 301 underwent low ligation (LL). The tumor size was larger in the HL group than in the LL group. The number of harvested lymph nodes (LNs) was higher in the HL group than in the LL group. There were no significant differences in complication rates and recurrence patterns between the groups. There were no significant differences in 5-year RFS and OS between the groups. Cox regression analysis revealed that the ligation level (HL vs. LL) was not a significant risk factor for oncological outcomes. Regarding functional outcomes, the LL group showed a significant recovery in defecatory function 1 year postoperatively compared with the HL group. CONCLUSION: LL with LNs dissection around the root of the IMA might not affect the oncologic outcomes comparing to HL; however, it has minimal benefit for defecatory function.

Comparative Bioactivity of Emamectin Benzoate Formulations against the Pine Wood Nematode, Bursaphelenchus xylophilus.

The pine wood nematode (PWN), Bursaphelenchus xylophilus is a well-known devastating pathogen of economic importance in the Republic of Korea and other countries. In the Republic of Korea, trunk injection of nematicides is the preferred method of control. In this study, the efficacy of 16 locally produced formulations of emamectin benzoate against the PWN are compared through determining their sublethal toxicities and reproduction inhibition potentials. Nematodes were treated with varying concentrations of the tested chemicals in multi-well culture plates, and rates of paralysis and mortality were determined after 24 h. Reproduction inhibition potential was tested by inoculating pre-treated nematodes onto Botrytis cinerea, and in pine twig cuttings. Despite the uniformity in the concentration of the active ingredient, efficacy was contrastingly different among formulations. The formulations evidently conformed to three distinct groups based on similarities in sublethal activity (group 1: LC95 of 0.00768-0.01443 mg/ml; group 2: LC95 of 0.03202-0.07236 mg/ml, and group 3: LC95 of as high as 0.30643-0.40811 mg/ml). Nematode paralysis generally occurred at the application dose of 0.0134-0.1075 µg/ml, and there were significant differences in nematode paralysis rates among the products. Nematode reproduction was only evident at lower doses both on B. cinerea and pine twigs, albeit the variations among formulations. Group 1 formulations significantly reduced nematode reproduction even at a lower dose of 0.001075 µg/ml. The variations in efficacy might be attributed to differences in inert ingredients. Therefore, there is need to analyze the potential antagonistic effects of the large number of additives used in formulations.

The Potency of Abamectin Formulations against the Pine Wood Nematode, Bursaphelenchus xylophilus.

Abamectin offers great protection against Bursaphelenchus xylophilus, a well-known devastating pathogen of pine tree stands. Trunk injection of nematicides is currently the most preferred method of control. This study aimed to evaluate the potency of the commonly used formulations of abamectin against B. xylophilus. Twenty-one formulations of abamectin were evaluated by comparing their sublethal toxicities and reproduction inhibition potentials against B. xylophilus. Nematodes were treated with diluted formulation concentrations in multi-well culture plates. And, populations pre-exposed to pre-determined concentrations of the formulations were inoculated onto Botrytis cinerea culture, and in pine twig cuttings. Potency was contrastingly different among formulations, with LC95 of 0.00285 and 0.39462 mg/ml for the most, and the least potent formulation, respectively. Paralysis generally occurred at an application dose of 0.06 µg/ml or higher, and formulations with high sublethal toxicities caused significant paralysis levels at the tested doses, albeit the variations. Nematode reproduction was evident at lower doses of 0.00053-0.0006 µg/ml both on Botrytis cinerea and pine twigs, with significant variations among formulations. Thus, the study highlighted the inconsistencies in the potency of similar product formulations with the same active ingredient concentration against the target organism, and the need to analyze the potential antagonistic effects of the additives used in formulations.

Stratification of rate of lymph node metastasis according to risk factors and oncologic outcomes in patients who underwent radical resection for rectal neuroendocrine tumors.

PURPOSE: Most predictive factors for lymph node metastasis in rectal neuroendocrine tumors (NETs) have been based on local and endoscopic resection. We aimed to evaluate the risk factors for lymph node metastasis in patients who underwent radical resection for rectal NETs and stratify the risk of lymph node metastasis. METHODS: Sixty-four patients who underwent radical resection for rectal NETs between January 2001 and January 2018 were included. We investigated the risk factors of lymph node metastasis using clinicopathologic data. We also performed a risk stratification for lymph node metastases using the number of previously known risk factors. For oncologic outcomes, the 5-year overall survival and recurrence-free survival were evaluated in both groups. RESULTS: Among the patients who underwent radical surgery, 32 (50.0%) had lymph node metastasis and 32 (50.0%) had non-lymph node metastasis. In the multivariable analysis, only the male sex was identified as a risk factor for lymph node metastasis (odds ratio, 3.695; 95% confidence interval, 1.128-12.105; P=0.031). When there were 2 or more known risk factors, the lymph node metastasis rate was significantly higher than when there were one or no risk factors (odds ratio, 3.667; 95% confidence interval, 1.023-13.143; P=0.046). There was also no statistical difference between the 2 groups in 5-year overall survival (P=0.431) and 5-year recurrence-free survival (P=0.144). CONCLUSION: We found that the rate of lymph node metastasis increased significantly when the number of known risk factors is 2 or more.