Mushroom Bodies Are Required for Learned Visual Navigation, but Not for Innate Visual Behavior, in Ants.

Visual navigation in ants has long been a focus of experimental study [1-3], but only recently have explicit hypotheses about the underlying neural circuitry been proposed [4]. Indirect evidence suggests the mushroom bodies (MBs) may be the substrate for visual memory in navigation tasks [5-7], while computational modeling shows that MB neural architecture could support this function [8, 9]. There is, however, no direct evidence that ants require MBs for visual navigation. Here we show that lesions of MB calyces impair ants' visual navigation to a remembered food location yet leave their innate responses to visual cues unaffected. Wood ants are innately attracted to large visual cues, but we trained them to locate a food source at a specific angle away from such a cue. Subsequent lesioning of the MB calyces using procaine hydrochloride injection caused ants to revert toward their innate cue attraction. Handling and saline injection control ants still approached the feeder. Path straightness of lesioned and control ants did not differ from each other but was lower than during training. Reversion toward the cue direction occurred irrespective of whether the visual cue was ipsi- or contralateral to the lesion site, showing this is not due simply to an induced motor bias. Monocular occlusion did not diminish ants' ability to locate the feeder, suggesting that MB lesions are not merely interrupting visual input to the calyx. The demonstrated dissociation between innate and learned visual responses provides direct evidence for a specific role of the MB in navigational memory.

E-cigarette use and its predictors: Results from an online cross-sectional survey in Poland.

INTRODUCTION: Since the invention of electronic cigarettes (ECs) in 2003, their use has spread worldwide; however, little is known about the profiles of EC users. Understanding the motivators for using ECs enables more accurate prediction of their use and more effective direction of pro-health activities. Our objective was to identify the factors that may influence the decision to use ECs and their possible adverse effects according to the experiences of EC users. METHODS: A cross-sectional online survey was administered between 1 July 2016 and 1 January 2017 among 1288 Polish-speaking users of social networks and EC forums. To explore associations between current EC use and other factors, multivariate binary logistic regression analyses were performed. RESULTS: The final analysis included 1142 survey participants: mean age 25.9 years (± 11.1), 85.6% were male, 50.3% had secondary education, 98.2% were Polish citizens, and 81.0% were current EC users. Male gender, lower education, aged ≤40 years, former cigarette smoking, previous attempts to quit smoking, perception of lack of harmful effects of ECs, perception of ECs as being tastier and cheaper than cigarettes, awareness of the advantages of ECs and their use as a smoking cessation aid were all statistically significant factors increasing the risk of EC use. The majority of study participants claimed that ECs are less addictive or not addictive compared to cigarettes (62.6%) and less harmful or not harmful (89.5%) compared to cigarettes. The most common reported side effects of ECs were dryness in the mouth (8.3%), itching in the throat (4.5%) and nausea (1.9%). CONCLUSIONS: Males aged ≤40 years with a lower level education were more likely to use ECs in the studied Polish population. The perception that ECs are less harmful than regular cigarettes is a factor increasing the odds of EC use; however, although ECs have few adverse effects, they nevertheless exist.

Outcome of pseudocysts complicating chronic pancreatitis.

BACKGROUND/AIMS: Pancreatic pseudocysts are frequent complication of chronic pancreatitis with incidence rate from 20 to 40%. The aim of our study was to establish a possible correlation between clinical features and outcome of pseudocysts complicating chronic pancreatitis. METHODOLOGY: We included in the study 37 patients with chronic pancreatitis and pancreatic pseudocysts treated at the Department of Digestive Tract Diseases of Lodz Medical University between 2003-2008. For each patients the following parameters were recorded: number and location of pseudocysts, diameter, kind of treatment, recurrence rate and time of hospitalisation. RESULTS: The mean size of pancreatic pseudocysts was 7.8 cm (range 2-16 cm). Spontaneous regression was observed in 7 pseudocysts (18.9%), persistence without symptoms and without size enlargement in 9 patients (24.3%). Twenty one (56.8%) pseudocysts required therapeutic intervention: endoscopic procedures (27.1%), surgical treatment (18,.9%) or percutaneous drainage (10.8%). Mean pseudocyst size for conservative treated patients was 4.2 compared to 9.6 for patients with interventional treatment (p < 0.05). The overall recurrence rate was 33.3%. The mean hospital stay of patients treated endoscopically was significantly shorter than those treated surgically (p < 0.01) and shorter than those of percutaneous drainage (p < 0.01). CONCLUSION: Pseudocysts treatment in chronic pancreatitis may be effectively achieved by both endoscopic and surgical means. Nonetheless, the endoscopic drainage, with lower hospitalization period, should be considered for initial therapy in each appropriate patients.

Assessment of frequency and safety of endoscopic retrograde cholangiopancreatography in patients over 80 years of age.

INTRODUCTION: Biliary and pancreatic diseases, especially choledocholithiasis and neoplastic diseases, are commonly seen in elderly patients. Endoscopic retrograde cholangiopancreatography (ERCP) is a diagnostic and therapeutic procedure performed more and more frequently also in elderly patients. OBJECTIVES: The aim of this study was to evaluate the utility and safety of ERCP in patients > 80 years of age. PATIENTS AND METHODS: We retrospectively analyzed 821 ERCP performed in the Department of Gastrointestinal Diseases, Medical University of Lódz in the years 2005-2007. We compared age, sex, clinical symptoms, laboratory findings, ERCP efficacy and safety in patients > 80 years of age versus younger subjects. RESULTS: ERCP was performed in 96 patients > 80 years of age (11.7%). ERCP-related complications occured in 48 (5.8%) patients, including 44 (6.1%) younger and 4 (4.2%) older subjects (p > 0.05). Acute pancreatitis was observed in 34 patients (32 [4.4%] younger and 2 [2.1%] older patients; p > 0.05). In 12 patients gastrointestinal hemorrhage and in 2 patients perforation were diagnosed. There was no statistical difference between the number of complications in the 2 compared patient groups. A mean length of hospital stay was similar in both groups, 4.8 days in the younger, and 5.7 days in older patients (p > 0.05). CONCLUSIONS: ERCP is a safe and effective method for diagnosis and treatment of both elderly and younger patients.