Sex-based differences in anti-predator response of crickets to chemical cues of a mammalian predator

Anti-predator behaviors like vigilance or hiding come at the expense of other fitness increasing behaviors such as foraging. To compensate for this trade-off, prey assess predation risk and modify the frequency of anti-predator behaviors according to the likelihood of the threat. In this study, we tested the ability of house crickets (Acheta domesticus) to indirectly assess predation risk via odors from a mammalian predator, Elliot\u27s short-tailed shrew (Blarina hylophaga). As natural differences in encounter rates and predation risk differs between sexes, we tested if male and female crickets perceive similar rates of predation risk from the presence of shrew odor measured via anti-predator behavioral response. Crickets were placed in enclosed, cardboard-lined chambers either treated with shrew odor or control, along with a food source. Time until foraging was measured for each individual and compared across treatment and sex. We found that in the presence of shrew odor, female crickets delayed foraging while males showed no response. These results suggest adult crickets can use chemical cues to detect mammalian predators. Furthermore, we demonstrate that female crickets associate greater predation risk from shrew predators than do male crickets, which are more stationary yet acoustically conspicuous. As predation risk potentially differs drastically for each sex, changes to the operational sex ratios of wild cricket populations could be influenced by the identity of the predator community

Anion emission from water molecules colliding with positive ions: Identification of binary and many-body processes

It is shown that negative ions are ejected from gas-phase water molecules when bombarded with positive ions at keV energies typical of solar-wind velocities. This finding is relevant for studies of planetary and cometary atmospheres, as well as for radiolysis and radiobiology. Emission of both H- and heavier (O- and OH-) anions, with a larger yield for H-, was observed in 6.6-keV 16O+ + H2O collisions. The ex-perimental setup allowed separate identification of anions formed in collisions with many-body dynamics from those created in hard, binary collisions. Most of the ani-ons are emitted with low kinetic energy due to many-body processes. Model calcu-lations show that both nucleus-nucleus interactions and electronic excitations con-tribute to the observed large anion emission yield.Comment: 5 pages, 4 figure

Local recurrence at the site of the Lone Star device through implantation of exfoliated cells during local excision for early rectal cancer:A case report

Introduction: Invasive procedures for colorectal cancer can cause iatrogenic tumor cell seeding. Implantation of these exfoliated cells in the surrounding tissue can result in locoregional cancer recurrence. This has been described in endoscopic procedures and major surgical resections, however recurrence in iatrogenic lesions of the anal canal during minimal invasive rectal surgery has not been shown in literature yet. This is the first reported case of recurrent rectal cancer that developed into an anal metastasis at the site where hooks of the Lone Star Retractor disrupted the epithelial lining of the anal canal during a local excision of early rectal cancer using TAMIS. Presentation of case: A 57 year old male was diagnosed with a high risk early stage rectal adenocarcinoma. He was treated with transanal minimally invasive surgery (TAMIS) with the use of a Lone Star retractor and he received subsequent chemo-radiotherapy. 23 months later the patient developed a bleeding mass bulging out of the anus. A true cut and incision biopsy was performed and the pathology report revealed localization of adenocarcinoma at the anal canal which was similar to the earlier diagnosed rectal carcinoma. The patient underwent an abdominal perineal resection and left-sided lymph node dissection. Discussion and conclusion: This shows that local recurrence through implantation of exfoliated tumor cells can occur in iatrogenic lesions of the anal canal not only in major but also in minimal invasive rectal surgery. Careful tissue handling and rectal washout may reduce the chance of this implantation metastasis.</p

Usefulness of CT scan as part of an institutional protocol for proactive leakage management after low anterior resection for rectal cancer

Purpose: Highly selective fecal diversion after low anterior resection (LAR) for rectal cancer requires a strict postoperative protocol for early detection of anastomotic leakage (AL). The purpose of this study was to evaluate C-reactive protein (CRP)–based CT imaging in diagnosis and subsequent management of AL. Methods: All patients that underwent a CT scan for suspicion of AL after transanal total mesorectal excision for rectal cancer in a university center (2015–2020) were included. Outcome parameters were diagnostic yield of CT and timing of CT and subsequent intervention. Results: Forty-four out of 125 patients underwent CT (35%) with an overall median interval of 5 h (IQR 3–6) from CRP measurement. The anastomosis was diverted in 7/44 (16%). CT was conclusive or highly suspicious for AL in 23, with confirmed AL in all those patients (yield 52%), and was false-negative in one patient (sensitivity 96%). CT initiated subsequent intervention after median 6 h (IQR 3–25). There was no or minor suspicion of AL on imaging in all 20 patients without definitive diagnosis of AL. After CT imaging on day 2, AL was confirmed in 0/1, and these proportions were 6/6 for day 3, 7/10 for day 4, 2/4 for day 5, and 9/23 beyond day 5. Conclusion: In the setting of an institutional policy of highly selective fecal diversion and pro-active leakage management, the yield of selective CT imaging using predefined CRP cut-off values was 52% with a sensitivity of 96%, enabling timely and tailored intervention after a median of 6 h from imaging.</p

Outcomes of patients with perforated colon cancer:A systematic review

Introduction: Perforated colon cancer (PCC) is a distinct clinical entity with implications for treatment and prognosis, however data on PCC seems scarce. The aim of this systematic review is to provide a comprehensive overview of the recent literature on clinical outcomes of PCC. Materials and methods: A systematic literature search of MEDLINE (PubMed), Embase, Cochrane library and Google scholar was performed. Studies describing intentionally curative treatment for patients with PCC since 2010 were included. The main outcome measures consisted of short-term surgical complications and long-term oncological outcomes. Results: Eleven retrospective cohort studies were included, comprising a total of 2696 PCC patients. In these studies, various entities of PCC were defined. Comparative studies showed that PCC patients as compared to non-PCC patients have an increased risk of 30-day mortality (8–33% vs 3–5%), increased post-operative complications (33–56% vs 22–28%), worse overall survival (36–40% vs 48–65%) and worse disease-free survival (34–43% vs 50–73%). Two studies distinguished free-perforations from contained perforations, revealing that free-perforation is associated with significantly higher 30-day mortality (19–26% vs 0–10%), lower overall survival (24–28% vs 42–64%) and lower disease-free survival (15% vs 53%) as compared to contained perforations. Conclusion: Data on PCC is scarce, with various PCC entities defined in the studies included. Heterogeneity of the study population, definition of PCC and outcome measures made pooling of the data impossible. In general, perforation, particularly free perforation, seems to be associated with a substantial negative effect on outcomes in colon cancer patients undergoing surgery. Better definition and description of the types of perforation in future studies is essential, as outcomes seem to differ between types of PCC and might require different treatment strategies.</p

Iatrogenic injury of the urinary tract during salvage procedures for pelvic sepsis:Experience of a national referral centre

Aim: This study aimed to determine the incidence, consequences and outcomes of iatrogenic urinary tract injury (IUI) during salvage surgery for pelvic sepsis.Method: Patients who underwent salvage surgery for pelvic sepsis after prior low anterior resection or Hartmann's procedure for rectal cancer were prospectively maintained in a database between 2010 and 2020 and reviewed retrospectively. The primary endpoint was the incidence of IUI. Secondary endpoints were timing of diagnosis (intra- vs. postoperative), reinterventions related to the IUI and healing of IUI. Results: In total 126 consecutive patients were included, and IUI occurred in 13 patients (10%). A ureteric injury occurred in eight patients, bladder injury in four patients and a urethral injury in one patient. All patients with an IUI had radiotherapy as neoadjuvant treatment. The IUI was diagnosed postoperatively in 63% (n = 8/13) with a median duration between surgery and diagnosis of the IUI of 10 days (IQR: 6–15). The median number of reinterventions was five (range 1–31) in the group with a postoperative diagnosis and one (range 0–1) in the group with an intraoperative diagnosis. Four patients required a surgical reintervention, all concerning injuries diagnosed postoperatively. At the end of follow-up, 85% of patients (n = 11/13) had a healed IUI. Conclusion: Iatrogenic urinary tract injury is not uncommon in salvage procedures for pelvic sepsis, even in an experienced tertiary referral centre. Most injuries were diagnosed postoperatively which affects the severity of these complications, emphasising the need to improve intraoperative diagnostic modalities.</p

Phase I study of gemcitabine using a once every 2 weeks schedule.

Gemcitabine (2',2'-difluorodeoxycytidine) is a novel nucleoside analogue. As part of a series of studies to determine the maximum tolerated dose (MTD) of gemcitabine and the most appropriate schedule, a two-centre phase I study of gemcitabine was undertaken in patients with advanced refractory solid tumours using a once every 2 weeks schedule. Fifty-two patients were entered into the study at 14 different dose levels (40-5700 mg m-2). Weekly evaluations for toxicity were performed and the MTD for this once every 2 weeks schedule was 5700 mg m-2. The dose-limiting toxicity was myelosuppression, with neutropenia being most significant. Other toxicities were nausea, vomiting, fever and asthenia. One minor response was seen in a heavily pretreated breast cancer patient treated at 1200 mg m-2. Preclinical studies suggest that the efficacy of gemcitabine is more schedule than dose related, and it is concluded that this is not the most appropriate dosing schedule for gemcitabine. However, this study demonstrates the safety profile of gemcitabine, as doses over fourfold greater than that recommended for the weekly schedule of 1000 mg m-2 could be tolerated

Phenoconversion from probable rapid eye movement sleep behavior disorder to mild cognitive impairment to dementia in a population-based sample

© 2017 The Authors Introduction Rapid eye movement sleep behavior disorder (RBD) is strongly associated with synucleinopathies. In 2012, we reported an increased risk of mild cognitive impairment (MCI) and Parkinson disease (PD) in cognitively normal Olmsted County, Minnesota, residents, aged 70 to 89 years with probable RBD. Here, we examine their progression to dementia and other neurodegenerative phenotypes. Methods Fifteen participants with RBD who were diagnosed with either MCI or PD were longitudinally followed, and their subsequent clinical courses were reviewed. Results Over 6.4 ± 2.9 years, six of the 14 participants with MCI developed additional neurodegenerative signs, five of whom had Lewy body disease features. Four of them progressed to dementia at a mean age 84.8 ± 4.9 years, three of whom met the criteria for probable dementia with Lewy bodies. One subject with PD developed MCI, but not dementia. Discussion Our findings from the population-based sample of Olmsted County, Minnesota, residents suggest that a substantial number of RBD patients tend to develop overt synucleinopathy features over time, and RBD patients who develop MCI and subsequent dementia have clinical features most consistent with dementia with Lewy bodies